Обучение по природни науки и върхови технологии

2020/5, стр. 595 - 611

APPLIED SAMPLING METHODOLOGY AND ANALYSIS OF NONLINEAR ACOUSTIC PROPERTIES IN SOLIDS OF REVOLUTION

G.I. Ivanov
E-mail: info@smg.bg
Sofia High School of Mathematics
61, Iskar St.
Sofia 1000, Bulgaria

Резюме: The main focus of this work is the research of the resulting sound caused by a constant airflow through the open end of a bottle by varying the relevant parameters. For a more in depth analysis, additional experiments with test tubes are carried out. The study aims to describe and document the influence of the parameters experimentally and with the help of theoretical apparatus, some of which are: Form, shape and material of the bottle, properties of the gas, filling agent. The aforementioned variables are defined and sorted on the basis of their effect on the process. Unpredicted acoustic properties emerge when the shape of the bottle is varied significantly. New methods for physical data collection such as an AFS (Acoustic Feedback System) and SRP (Solids of Revolution Parameterization) are introduced and compared to the already existing ones, in order to better equate for the emergent acoustic properties. For a holistic evaluation various samples and relations from the well-described acoustic properties are tested against their contemporary physical description for their predictive power. Similar methods are introduced to the analysis of the previously undescribed acoustic phenomena and presented with a multi-layered approach for full comparison.

Ключови думи: acoustic feedback system; airflow system; solid of revolution; resonance; Helmholtz resonance; standing wave

From the Research Laboratories

1. Introduction

The contemporary theoretical modelling fails to account for the full spectral range of the acoustic feedback from a tested system. Present approximations, such as “Helmholtz Resonance” and “Standing Wave Resonance”, are ubiquitously applied, yet are not enough to describe emergent acoustic phenomena. The methodology of acoustic excitation is crucial for the accurate data gathering and minimization of external influences, foreign to the acoustic system. All of the aforementioned observations are fundamental to the motivations of conducting this research.

2. Experimental Setup

Two methods for data collection are described. The results from the systems will be compared in the section “Experimental Results”, labelled for their respective origin (AS/AFS). In both instances the sound is recorded and analysed with the audio editing software “Audacity”. For setup one the signal transformations are carried out by the software and for AFS - done as described in section “Background”.

2.1 Airflow System (AS)

An SR (Solid of Revolution) and a stationary microphone are positioned with the space between them a constant - 0,5 m. This provides consistency in the data, which allows for their simultaneous application as a basis for comparison; For minimizing the fluctuations of the speed of air, the airflow is supplied with a hot air gun at a constant setting of 30 C; The basic mechanism is that of “Acoustic Excitation”, where the resonant modes are respectively excited and produce a descriptive frequency.

2.2 Acoustic Feedback System (AFS)

This method for data acquisition was developed for minimizing external and background noise and focuses on the acoustic feedback, given by the system. The SR is positioned above a speaker and under a microphone (Fig.1). A sweep signal (Linear-Frequency Chirp) with time-domain function:

is introduced in the system, where the feedback is then reinforced for a multi-layered approach. This method entails the continuous damping or amplification of the frequencies that are respectively foreign or natural to the system. The current analysis focuses only on feedback of rank 1 (first-time response of the system). Future

experiments will be extensively dedicated on higher-order feedback.Fig. 1:AFS3. Background

Section “Background” is focused on the signal analysis and the existing theoretical models, which in turn are reviewed for their respective assumptions and func

tional range. Novel parameterizations for the description of the physical bodies are introduced and evaluated.

3.1 Resonance

A specific section, dedicated to the topic of resonance, is required for clearing up the reason behind the phenomenon and validating the newly introduced experimental setup (AFS): A phenomenon of resonance is observed when the frequency of a forced vibration approaches the natural frequency of the system and in the process is amplified. The mechanism of occurrence is the transfer of energy between two or more different modes. The mechanism of an AFS utilizes this phenomenon in the process of looping the feedback from the acoustic system - The continuous damping of the foreign frequency to the system, coupled with the amplification of the natural resonant modes leads to obtaining a clear spectrum of the acoustic properties of a given SR.

The type air column resonates, which fundamentally presupposes a recurrent oscillation (It is important to mention that the different resonant modes have). For a periodic signal the following relation is true:

3.2 Signal Analysis In order the audio signal to be processed and used as data a few transformations are required. The audio signal is recorded in small samples, making the setup a discrete-time system (Fig.6). The given data points are obtained from the DAQ Setup (Data

Acquisition).Fig. 2:Sampl Signalofsignalthatan AFSworkswithisperiodic-theexcited

Where N is the minimum integer for which the relation holds and is called a period. We define energy of the signal as:

A periodic signal has infinite energy over n = (- ∞, + ∞), but the average power over n = (- ∞, + ∞) is finite and equal to the power, calculated over a single period:

Any discrete-time signal can be expressed as a sum of scaled and delayed impulses

When applied to the physical context relation (2) becomes the functional dependence of the sound pressure (p) to the moment of time (t):

When we are working with complex systems such as the acoustic properties of SRs, the resonant modes of the system become many and hard to theoretically model. Nonetheless from the properties of mechanic waves in an ideal gas, we also know that the sound pressure at a given time of (t) is equal to the sum of the partial sound pressures from the different resonant modes, so relation (5) becomes:

Where every is some acoustic oscillation:

And (7) becomes (9) which clearly fits the formula for DFT (Discrete Fourier Transform) (10):

We can redefine the energy definition (3) in relation to the given time series:

The aforementioned relation (11) is equal to the sum of the square of its FT (Fourier Transform) as follows from the Parseval’s Theorem:

Where the ): is the already familiar transform in relation to the time-series (and

Since the integral on the right-hand side of (12) is the energy of the signal, the integrand can be interpreted as a density function describing the energy per unit frequency contained in the signal at the frequency f. In light of this, the

energy spectral density of a signal

x(t) is defined as:

The same transformations can be done for the power of the given signal in relation to the time series:

And following the same process as for the Energy Spectral Density we can de

rive the final expression:

To put this in the physical context - the equivalent physical signal in relation to the time series is that of the sound pressure p(t):

Therefore the spectral density function is:

mean squared Where acoustic pressure, is the which in average turn gives contribution per from a band of frequencies between and us the contribution to unit bandwidth to the

Following from the aforementioned transformations we can then deduce the resulting sound-pressure spectrum level from (19) by using the definition for dB representation:

Which in turn for our theoretical basis can be adapted simply as:

The aforementioned transformations are applied to the signal to acquire the training data for the machine learning solutions. Due to the required vectorization of the given data points, a few manual transformations are done in order to have the necessary format. For example, physically the most adequate representation of the data lem in relation to the fundamental frequency would deem . The proband is the that rest this of transformation the values of would make without the a maximum particular value limit. of For this reason, the best way is to scale down the spectrum to one that is represented by values of

- This is done by formulating the new in the following way: This in turn will allow for the analysis in section “Parameter Correlation” with parameter a.

3.3 Existing Models

There are several existing models describing the acoustic properties of the oscillating air within a cavity, based on its form. The problem is that despite the accurate results in their functional range, they are still highly limited in their predictive power for the whole spectrum. This section is split into two parts dedicated respectively to each model and focuses on finding the border cases and their reason for emergence. Particular corrections to the definitions of the parameters are applied a thorough explanation is present in the subsection “Experimental correction”. Each of the models is used for the description of a particular phenomenon. For clarity purposes at the point of application the reasoning behind it is cleared.

The described models are:

3.3.1 Helmholtz Resonance

The original experiment is carried out with a specifically created object that is spherical and has a great relative difference between the radius of the cross section of the open end and the widest part, as seen from (Fig.4). This allows for modelling the movement of the air as a separate oscillation of a mass (m), where the rest of the volume acts as a spring. The speed with which the process happens is high, which then allows us to assume that the process is insulated):

adiabatic(thesystemisthermallythecrosssectionandthelengthofcavity. Withthis model wecan makethe

Where c is the speed of sound, S and L are neck respectively, and V is the volume of the the following observations:

The shape has to be spherical with a clearly-defined neck.

The cavity is functionally described with just 3 parameters - Volume, Length of neck and Area of the open end. This entails a very big variation in the plausible shape, when describing a particular SR (Solid of Revolution).

3.3.2 Experimental Correction

Throughout the experiments a certain trend can be seen. By just using the Helmholtz model (1) the theoretically predicted frequencies are a lot higher than the recorded values. It is estimated that a correction is necessary. The conventional definition of the neck is the cylinder on the top of the volume. From our experiments this proved to be a fairly inaccurate estimation. The newly defined value can be empirically deduced from the following functional relations:

This can be then tested by changing the apparent volume of the cavity with some value of

After an empirical examination a claim can be made of the physical background for such a difference in - The air volume is active in L equal to the distance between the open end and the widest point of the SR. Fig (4) shows a table with some of the corrected values.

3.3.3 Standing Wave

In the case of the aforementioned model the subject of study is the oscillation of an air column within a cylinder. The expression describing the process has several variations. In the context of this work only two are used - a cylinder open at both ends and a cylinder open at one end. In this model there are clearly defined nodes (zero displacement) and anti-nodes (maximum displacement). This entails the presence of secondary harmonic oscillations because of the possibility to fit different patterns of air column displacements that fulfil the conditions.

Open at both ends (2.1) –as it is discussed later, this applies to the harmonic oscillations of the air within the neck of the SR (if present). In the equation n is the number of the harmonic oscillation (n = 1 is the fundamental frequency) and can have the value of any integer (n = 1, 2, 3... n). An illustration can be found in the “Appendix”.

Open at one end (2.2) - this describes the oscillation of the air column within a cylinder with one open end and as it is later seen, it also applies to any SR with one open end. In the equation n is the number of the harmonic oscillation (n = 1 is the fundamental frequency) and can have the value of any odd integer (n = 1, 3, 5... n).

3.4 Solids of Revolution Parameterization

As it is seen in the “Analysis” section the familiar parameterization of V, L, H and S is useful for determining particular frequencies, but is far from enough to describe the full acoustic properties, some of which are very important for their various applications. For this reason a new parameterization is introduced, in order to fully describe the given properties of the system. If we follow this line of reasoning the best parameterization of an object/cavity would be a 3-D render. The problem with such a method of course is that it is very resource-draining and experimentally hard to determine. This creates the need for a more optimal, but still an accurate estimation of the given shape. For this reason the Solids of Revolution Parameterization is introduced. Thus far all experiments are carried out with bodies that fit the description of a SR that is a shape that can be represented mathematically as the integral of a particular curve around the axis of symmetry:

Where the volume of the SR can be represented with the following expression:

A similar method of discrete sampling (in the section Signal Analysis) needs to be introduced in order for the parameterization to serve as input data. For this reason a process of sampling the SRs is created, where different shapes and dimensions are represented with the same sample size. The process of sampling goes through outlining the silhouette of the SR from a photo and then sampling equidistant points.

This method allows for customization and modulation of the sample size an optimization can be made based on the preferred goal - accuracy or resource efficiency. On the x-axis the coordinates vary from 0 (at the base of the SR) to h, which is respectively the height of the SR. In our case the dimensions of [x] = meters for optimization purposes - as such every , for every tested SR is under 1 m in height. If necessary for the application redefinitions of the dimensions can easily be made.

A sample point is , following the relation of , where and The data follows to be represented in a matrix, where:

distant A point is sampling, where , following the and relation of After vectorization for (for the equi use as input data, we get :

4. Experimental results & Analysis

This section is dedicated to the experimental results from the 2 acoustic systems - AS & AFS and their analysis using the different methods, presented in section Background. The main focus is the evaluation of the produced data and the review of the achieved results with the various models. A few methods of increasing substantially the size of the datasets are discussed in the subsections Volume & Length of the neck

4.1 Methods for increasing the size of the datasets

The main problem with collecting physical data is that it is highly inefficient and almost impossible to do experiments with 1000+ bottles in order to achieve a sufficient database to make any claims onto the validity of the data. For that reason the following two methods are presented in order to tackle the fundamental problem we have with physical systems. Two ways to increase substantially the given datasets is by varying the acoustic properties of a single SR. By applying them we can achieve a highly increased efficiency in the data we can gather from using only one SR. That is possible by displacing the air within the cavity with a form of a medium, which does not itself change the acoustic properties other than with its own volume (as it can be seen in the subsection Filling agent). Another form of variation is discussed in subsection Length of the neck, where by respectively elongating the neck of the given cavity, the acoustic properties change themselves. The aforementioned methods are used in order to produce more training data - this allows for more than 100x10 acoustic variations per SR.

4.1.1 Volume In this subsection water is used as a filling medium to the acoustic cavity. The air that previously filled the SR is displaced, and thus directly changing the volume that influences the process (described through the physical terms of the Helmholtz model (1) - a change in the air that acts as a spring). The reason behind using water as a filling medium rather than other variants is examined in the subsection “Filling agent”. As it can be seen in the charts bellow, with just one SR a lot of sample sizes

can be achieved by simply displacing the air in the acoustic cavity.

4.1.2 Filling Agent

The way that the volume is displaced is by using some kind of a filling agent. This section proves that the effect the filling agent has on the acoustic properties is just with its effective volume. The following experiments are done by adding glycerol to the system - a fluid that is a lot more dense and viscous than water and yet the results are within the range of error.

4.1.3 Length of the neck

By simply elongating the open end of the SRs a lot more sampling data can be achieved. The physical basis of this method is the increase in the travelled distance by the air (Model (1) - Helmholtz).

4.2 AS Experimental Results & Theoretical Models This section is focused on reviewing the data from the first experimental setup (AS). Observations will be made on what parameters affect this particular system and the validity of the results.

From all for the presented spectra can be observed various frequency peaks and disturbances. To all of them there are recurrent patterns between the various frequencies that can easily be deduced as the secondary oscillations to the system. Average accuracy per noted peak on the table is 94%.

4.3 AFS Experimental Setup & Data Analysis

On the table below are depicted the initial input signal (AF1) and the respective acoustic response, given by the system for SR B1. Basing our reasoning on the physical phenomenon of Resonance described in the subsection from Background with the same name, we can claim that every peak, resting above the line of (AF1) is that of a resonant mode due to the observed amplification.

Usingthe AFSmethodwearetoexpectagreateraccuracyduetotheelimination ofalot ofthe backgroundnoiseand errorsfrom theprogram. Thiscanbe seenfrom the slight increase in accuracy of98%for the applied models at the peaks.5. Transitional FormsInthecaseofsomebottlesthereareemergentacousticpropertiesthatarenotdescribed bythe aforementionedmodels. On Fig.19, 20,21 и22 thereare particularpeaksthataredifferentthanthefundamentalfrequency. Afterashortanalysisthemainpeakscanbeattributedtothesecondaryharmonicoscillationsoftheair--

within the ence of peak neck of the After a bottle comparison it can A more be seen interesting observation that the value of that is the frequency prescorresponds to the resonant one in a cylinder that is open at one end and has the height of the investigated bottle. From those observations a conclusion can be made about the actual resonance in the bottle and it is the fact that the air oscillates with simultaneously with different frequencies. For some bottles the peak is not that pronounced (the loudness is lower). A possible reason behind this phenomenon can be attributed to the shape of the bottle, which is studied in the following section.

6. Shape

The hypothesis that is tested in this section assumes that the shape determines the ratio between the loudness of the peaks from the two models. In the expression of the Helmholtz resonance there are 3 defining parameters. Those values do not serve as a sufficient condition to unambiguously depict the shape of the bottle. It is possible that for the same values of those 3 parameters, there could be significant variation in its contour. In subsections “Relation between the two models” and “Parametric correlation” a method for testing the influence of the shape is laid out.

6.1 Correlation between the two models

For the hypothesis to be a valid claim (that the shape of the bottle is what determines the emergent properties). The ratio between the two peaks ( ) has to stay a constant. On Fig.23 the ratio between the loudnesses is plotted against the time. The ratio stays fixed, which then allows us to make the claim that it is dependent on the shape of the bottle.

6.2 Parametric Correlation

The parameter, investigated in this subsection, is , where is the radius at the widest section from the bottle and R is the radius at open end. Hypothetically a cylinder a lot smaller than would have an the . By definition the Helmholtz model has a neck, a lot smaller than one acoustic cavityIn . For the ideal this reason case the it ratio is to be between expected the that loudness is

,Because in a cylinder there is no Helmholtz resonance).ofthetwopeakswouldapproachinnityasaapproaches1:

On Fig.24 there is a positive correlation, so the graph suggests a relationship between the parameter a and the formation of the 2 models. As it it is evident, the loudness of the frequency from (2.2) increases while the fundamental frequency (1) decreases. This proves that the shape has an influence, undocumented before. It is important to note that the relationship is not linear. What is seen is the local derivative of the function. Methods with which the relationship could be found are proposed in subsection “Analysis for future optimization”.

7. Applications

The project is structured in such a way, that every section has a personal contribution and an application for it, which in turn can be used independently or simultaneously with the other. The main focuses are:

Acoustic Feedback System (AFS) - The construction of the AFS allowed for full optimization of the produced data and an empirical way of determining the acoustic modes. The applications fall in various fields like music instrument tuning, spatial mapping, metal vapour lasers and more. The mechanism of \Positive Feedback is used in various resonant systems, reaching further than even the field of acoustics.

Solids of Revolution Parameterization (SRP) - This is a method of transforming 3-D symmetric objects into matrix form with different sample sizes and then be utilized for various algorithms and forthcoming theoretical models. Its application falls in the fields of nonlinear and spatial acoustics, as well as acoustic-tracing.

8. Educational Value

The general setup of the experiment provides and inexpensive and efficient way of studying fundamental concepts in acoustics. The study of the corresponding physical modelling can be done on multiple educational levels, making it an accessible and interesting project for high schoolers and students alike. In acoustics the ability to model resonances and spectra without excessive mathematical apparatuses is hard to come by, making this an important introductory experiment into the field. For example, similar versions of the problem have been used in the IYNT and the IYPT, both of which are international tournaments in science for high schoolers. In the case of those competitions, the problem can be developed without using calculus or any university - level math (such is the appeal of the “Helmholtz resonance”). As with any physics problem, the possible development of this experiment does not end with the simple concepts, mentioned in this paper, and provides yet unexplored opportunities for research.

9. Concluding Remarks

The contemporary theoretical modelling fails to account for the full spectral range of the acoustic feedback from the tested system. This project focused on developing different methods for solving that problem by introducing more effective empirical and sampling methods (namely AFS & SRP). There are indications in the effectiveness of the newly-introduced AFS and SRP methods: The developed signal transformations and experimental setup are what is to prove crucial in the following analysis and experiments.

REFERENCES

Epperlein, J.P. & Bamieh, B. (2012). A Frequency Domain Method for Optimal Periodic Control. American Control Conference

Burgess, J.C. (1991). Chirp design for acoustic system identification. J. Acoust. Soc. Am. 91 (3)

Forssell, U. & Ljung, L. (1998). Closed-loop identification revisited, Automatica 35

Illingworth, S. J., Morgans, A. S. & Rowley, C. W. (2011). Feedback control of flow resonances using balanced reduced-order models. Journal of Sound and Vibration 330

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Lyubomir Lazov, Hristina Deneva, Galina Gencheva

2019 година
Книжка 6
LASER MICRO-PERFORATION AND FIELDS OF APPLICATION

Hristina Deneva, Lyubomir Lazov, Edmunds Teirumnieks

ПРОЦЕСЪТ ДИФУЗИЯ – ОСНОВА НА ДИАЛИЗАТА

Берна Сабит, Джемиле Дервиш, Мая Никова, Йорданка Енева

IN VITRO EVALUATION OF THE ANTIOXIDANT PROPERTIES OF OLIVE LEAF EXTRACTS – CAPSULES VERSUS POWDER

Hugo Saint-James, Gergana Bekova, Zhanina Guberkova, Nadya Hristova-Avakumova, Liliya Atanasova, Svobodan Alexandrov, Trayko Traykov, Vera Hadjimitova

Бележки върху нормативното осигуряване на оценяването в процеса

БЕЛЕЖКИ ВЪРХУ НОРМАТИВНОТО ОСИГУРЯВАНЕ, НА ОЦЕНЯВАНЕТО В ПРОЦЕСА НА ОБУЧЕНИЕТО

ТЕХНОЛОГИЯ

Б. В. Тошев

Книжка 5
ON THE GENETIC TIES BETWEEN EUROPEAN NATIONS

Jordan Tabov, Nevena Sabeva-Koleva, Georgi Gachev

Иван Странски – майсторът на кристалния растеж [Ivan Stranski

ИВАН СТРАНСКИ – МАЙСТОРЪТ, НА КРИСТАЛНИЯ РАСТЕЖ

Книжка 4

CHEMOMETRIC ANALYSIS OF SCHOOL LIFE IN VARNA

Radka Tomova, Petinka Galcheva, Ivajlo Trajkov, Antoaneta Hineva, Stela Grigorova, Rumyana Slavova, Miglena Slavova

ЦИКЛИТЕ НА КРЕБС

Ивелин Кулев

Книжка 3
ПРИНЦИПИТЕ НА КАРИЕРНОТО РАЗВИТИЕ НА МЛАДИЯ УЧЕН

И. Панчева, М. Недялкова, С. Кирилова, П. Петков, В. Симеонов

UTILISATION OF THE STATIC EVANS METHOD TO MEASURE MAGNETIC SUSCEPTIBILITIES OF TRANSITION METAL ACETYLACETONATE COMPLEXES AS PART OF AN UNDERGRADUATE INORGANIC LABORATORY CLASS

Anton Dobzhenetskiy, Callum A. Gater, Alexander T. M. Wilcock, Stuart K. Langley, Rachel M. Brignall, David C. Williamson, Ryan E. Mewis

THE 100

Maria Atanassova, Radoslav Angelov

A TALE OF SEVEN SCIENTISTS

Scerri, E.R. (2016). A Tale of Seven Scientists and a New Philosophy of Science.

Книжка 2
DEVELOPMENT OF A LESSON PLAN ON THE TEACHING OF MODULE “WATER CONDUCTIVITY”

A. Thysiadou, S. Christoforidis, P. Giannakoudakis

AMPEROMETRIC NITRIC OXIDE SENSOR BASED ON MWCNT CHROMIUM(III) OXIDE NANOCOMPOSITE

Arsim Maloku, Epir Qeriqi, Liridon S. Berisha, Ilir Mazreku, Tahir Arbneshi, Kurt Kalcher

THE EFFECT OF AGING TIME ON Mg/Al HYDROTALCITES STRUCTURES

Eddy Heraldy, Triyono, Sri Juari Santosa, Karna Wijaya, Shogo Shimazu

Книжка 1
A CONTENT ANALYSIS OF THE RESULTS FROM THE STATE MATRICULATION EXAMINATION IN MATHEMATICS

Elena Karashtranova, Nikolay Karashtranov, Vladimir Vladimirov

SOME CONCEPTS FROM PROBABILITY AND STATISTICS AND OPPORTUNITIES TO INTEGRATE THEM IN TEACHING NATURAL SCIENCES

Elena Karashtranova, Nikolay Karashtranov, Nadezhda Borisova, Dafina Kostadinova

45. МЕЖДУНАРОДНА ОЛИМПИАДА ПО ХИМИЯ

Донка Ташева, Пенка Василева

2018 година
Книжка 6

ЗДРАВЕ И ОКОЛНА СРЕДА

Кадрие Шукри, Светлана Великова, Едис Мехмед

РОБОТИКА ЗА НАЧИНАЕЩИ ЕНТУСИАСТИ

Даниела Узунова, Борис Велковски, Илко Симеонов, Владислав Шабански, Димитър Колев

DESIGN AND DOCKING STUDIES OF HIS-LEU ANALOGUES AS POTENTIOAL ACE INHIBITORS

Rumen Georgiev, , Tatyana Dzimbova, Atanas Chapkanov

X-RAY DIFFRACTION STUDY OF M 2 Zn(TeО3)2 (M - Na, K) ТELLURIDE

Kenzhebek T. Rustembekov, Mitko Stoev, Aitolkyn A. Toibek

CALIBRATION OF GC/MS METHOD FOR DETERMINATION OF PHTHALATES

N. Dineva, I. Givechev, D. Tanev, D. Danalev

ELECTROSYNTHESIS OF CADMIUM SELENIDE NANOPARTICLES WITH SIMULTANEOUS EXTRACTION INTO P-XYLENE

S. S. Fomanyuk, V. O. Smilyk, G. Y. Kolbasov, I. A. Rusetskyi, T. A. Mirnaya

БИОЛОГИЧЕН АСПЕКТ НА РЕКАНАЛИЗАЦИЯ С ВЕНОЗНА ТРОМБОЛИЗА

Мариела Филипова, Даниела Попова, Стоян Везенков

CHEMISTRY: BULGARIAN JOURNAL OF SCIENCE EDUCATION ПРИРОДНИТЕ НАУКИ В ОБРАЗОВАНИЕТО VOLUME 27 / ГОДИНА XXVII, 2018 ГОДИШНО СЪДЪРЖАНИЕ СТРАНИЦИ / PAGES КНИЖКА 1 / NUMBER 1: 1 – 152 КНИЖКА 2 / NUMBER 2: 153 – 312 КНИЖКА 3 / NUMBER 3: 313 – 472 КНИЖКА 4 / NUMBER 4: 473 – 632 КНИЖКА 5 / NUMBER 5: 633 – 792 КНИЖКА 6 / NUMBER 6: 793 – 952 КНИЖКА 1 / NUMBER 1: 1 – 152 КНИЖКА 2 / NUMBER 2: 153 – 312 КНИЖКА

(South Africa), A. Ali, M. Bashir (Pakistan) 266 – 278: j-j Coupled Atomic Terms for Nonequivalent Electrons of (n-1)fx and nd1 Configurations and Correlation with L-S Terms / P. L. Meena (India) 760 – 770: Methyl, тhe Smallest Alkyl Group with Stunning Effects / S. Moulay 771 – 776: The Fourth State of Matter / R. Tsekov

Книжка 5
ИМОБИЛИЗИРАНЕНАФРУКТОЗИЛТРАНСФЕРАЗА ВЪРХУКОМПОЗИТНИФИЛМИОТПОЛИМЛЕЧНА КИСЕЛИНА, КСАНТАН И ХИТОЗАН

Илия Илиев, Тонка Василева, Веселин Биволарски, Ася Виранева, Иван Бодуров, Мария Марудова, Теменужка Йовчева

ELECTRICAL IMPEDANCE SPECTROSCOPY OF GRAPHENE-E7 LIQUID-CRYSTAL NANOCOMPOSITE

Todor Vlakhov, Yordan Marinov, Georgi. Hadjichristov, Alexander Petrov

ON THE POSSIBILITY TO ANALYZE AMBIENT NOISERECORDED BYAMOBILEDEVICETHROUGH THE H/V SPECTRAL RATIO TECHNIQUE

Dragomir Gospodinov, Delko Zlatanski, Boyko Ranguelov, Alexander Kandilarov

RHEOLOGICAL PROPERTIES OF BATTER FOR GLUTEN FREE BREAD

G. Zsivanovits, D. Iserliyska, M. Momchilova, M. Marudova

ПОЛУЧАВАНЕ НА ПОЛИЕЛЕКТРОЛИТНИ КОМПЛЕКСИ ОТ ХИТОЗАН И КАЗЕИН

Антоанета Маринова, Теменужка Йовчева, Ася Виранева, Иван Бодуров, Мария Марудова

CHEMILUMINESCENT AND PHOTOMETRIC DETERMINATION OF THE ANTIOXIDANT ACTIVITY OF COCOON EXTRACTS

Y. Evtimova, V. Mihailova, L. A. Atanasova, N. G. Hristova-Avakumova, M. V. Panayotov, V. A. Hadjimitova

ИЗСЛЕДОВАТЕЛСКИ ПРАКТИКУМ

Ивелина Димитрова, Гошо Гоев, Савина Георгиева, Цвета Цанова, Любомира Иванова, Борислав Георгиев

Книжка 4
PARAMETRIC INTERACTION OF OPTICAL PULSES IN NONLINEAR ISOTROPIC MEDIUM

A. Dakova, V. Slavchev, D. Dakova, L. Kovachev

ДЕЙСТВИЕ НА ГАМА-ЛЪЧИТЕ ВЪРХУ ДЕЗОКСИРИБОНУКЛЕИНОВАТА КИСЕЛИНА

Мирела Вачева, Хари Стефанов, Йоана Гвоздейкова, Йорданка Енева

RADIATION PROTECTION

Natasha Ivanova, Bistra Manusheva

СТАБИЛНОСТ НА ЕМУЛСИИ ОТ ТИПА МАСЛО/ ВОДА С КОНЮГИРАНА ЛИНОЛОВА КИСЕЛИНА

И. Милкова-Томова, Д. Бухалова, К. Николова, Й. Алексиева, И. Минчев, Г. Рунтолев

THE EFFECT OF EXTRA VIRGIN OLIVE OIL ON THE HUMAN BODY AND QUALITY CONTROL BY USING OPTICAL METHODS

Carsten Tottmann, Valentin Hedderich, Poli Radusheva, Krastena Nikolova

ИНФРАЧЕРВЕНА ТЕРМОГРАФИЯ ЗА ДИАГНОСТИКА НА ФОКАЛНА ИНФЕКЦИЯ

Рая Грозданова-Узунова, Тодор Узунов, Пепа Узунова

ЕЛЕКТРИЧНИ СВОЙСТВА НА КОМПОЗИТНИ ФИЛМИ ОТ ПОЛИМЛЕЧНА КИСЕЛИНА

Ася Виранева, Иван Бодуров, Теменужка Йовчева

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ТРИ ИДЕИ ЗА ЕФЕКТИВНО ОБУЧЕНИЕ

Гергана Карафезиева

МАГИЯТА НА ТВОРЧЕСТВОТО КАТО ПЪТ НА ЕСТЕСТВЕНО УЧЕНЕ В УЧЕБНИЯ ПРОЦЕС

Гергана Добрева, Жаклин Жекова, Михаела Чонос

ОБУЧЕНИЕ ПО ПРИРОДНИ НАУКИ ЧРЕЗ МИСЛОВНИ КАРТИ

Виолета Стоянова, Павлина Георгиева

ИГРА НА ДОМИНО В ЧАС ПО ФИЗИКА

Росица Кичукова, Ценка Маринова

ПРОБЛЕМИ ПРИ ОБУЧЕНИЕТО ПО ФИЗИКА ВЪВ ВВМУ „Н. Й. ВАПЦАРОВ“

А. Христова, Г. Вангелов, И. Ташев, М. Димидов

ИЗГРАЖДАНЕ НА СИСТЕМА ОТ УЧЕБНИ ИНТЕРНЕТ РЕСУРСИ ПО ФИЗИКА И ОЦЕНКА НА ДИДАКТИЧЕСКАТА ИМ СТОЙНОСТ

Желязка Райкова, Георги Вулджев, Наталия Монева, Нели Комсалова, Айше Наби

ИНОВАЦИИ В БОРБАТА С ТУМОРНИ ОБРАЗУВАНИЯ – ЛЕЧЕНИЕ ЧРЕЗ БРАХИТЕРАПИЯ

Георги Върбанов, Радостин Михайлов, Деница Симеонова, Йорданка Енева

NATURAL RADIONUCLIDES IN DRINKING WATER

Natasha Ivanova, Bistra Manusheva

Книжка 2

АДАПТИРАНЕ НА ОБРАЗОВАНИЕТО ДНЕС ЗА УТРЕШНИЯ ДЕН

И. Панчева, М. Недялкова, П. Петков, Х. Александров, В. Симеонов

STRUCTURAL ELUCIDATION OF UNKNOWNS: A SPECTROSCOPIC INVESTIGATION WITH AN EMPHASIS ON 1D AND 2D 1H NUCLEAR MAGNETIC RESONANCE SPECTROSCOPY

Vittorio Caprio, Andrew S. McLachlan, Oliver B. Sutcliffe, David C. Williamson, Ryan E. Mewis

j-j Coupled Atomic Terms for Nonequivalent Electrons of (n-1)f

j-jCOUPLEDATOMICTERMSFORNONEQUIVALENT, ELECTRONS OF (n-f X nd CONFIGURATIONS AND, CORRELATION WITH L-S TERMS

INTEGRATED ENGINEERING EDUCATION: THE ROLE OF ANALYSIS OF STUDENTS’ NEEDS

Veselina Kolarski, Dancho Danalev, Senia Terzieva

Книжка 1
ZAGREB CONNECTION INDICES OF TiO2 NANOTUBES

Sohaib Khalid, Johan Kok, Akbar Ali, Mohsin Bashir

SYNTHESIS OF NEW 3-[(CHROMEN-3-YL)ETHYLIDENEAMINO]-PHENYL]-THIAZOLIDIN-4ONES AND THEIR ANTIBACTERIAL ACTIVITY

Ramiz Hoti, Naser Troni, Hamit Ismaili, Malesore Pllana, Musaj Pacarizi, Veprim Thaçi, Gjyle Mulliqi-Osmani

2017 година
Книжка 6
GEOECOLOGICAL ANALYSIS OF INDUSTRIAL CITIES: ON THE EXAMPLE OF AKTOBE AGGLOMERATION

Zharas Berdenov, Erbolat Mendibaev, Talgat Salihov, Kazhmurat Akhmedenov, Gulshat Ataeva

TECHNOGENESIS OF GEOECOLOGICAL SYSTEMS OF NORTHEN KAZAKHSTAN: PROGRESS, DEVELOPMENT AND EVOLUTION

Kulchichan Dzhanaleyeva, Gulnur Mazhitova, Altyn Zhanguzhina, Zharas Berdenov, Tursynkul Bazarbayeva, Emin Atasoy

СПИСАНИЕ ПРОСВѢТА

Списание „Просвета“ е орган на Просветния съюз в България. Списанието е излизало всеки месец без юли и август. Годишният том съдържа 1280 стра- ници. Списанието се издава от комитет, а главен редактор от 1935 до 1943 г. е проф. Петър Мутафчиев, историк византолог и специалист по средновеков-

Книжка 5
47-А НАЦИОНАЛНА КОНФЕРЕНЦИЯ НА УЧИТЕЛИТЕ ПО ХИМИЯ

В последните години тези традиционни за българското учителство конфе- ренции се организират от Българското дружество по химическо образование и история и философия на химията. То е асоцииран член на Съюза на химици- те в България, който пък е член на Европейската асоциация на химическите и

JOURNALS OF INTEREST: A REVIEW (2016)

BULGARIAN JOURNAL OF SCIENCE AND EDUCATION POLICY ISSN 1313-1958 (print) ISSN 1313-9118 (online) http://bjsep.org

INVESTIGATING THE ABILITY OF 8

Marina Stojanovska, Vladimir M. Petruševski

SYNTHESIS OF TiO -M (Cd, Co, Mn)

Candra Purnawan, Sayekti Wahyuningsih, Dwita Nur Aisyah

EFFECT OF DIFFERENT CADMIUM CONCENTRATION ON SOME BIOCHEMICAL PARAMETERS IN ‘ISA BROWN’ HYBRID CHICKEN

Imer Haziri, Adem Rama, Fatgzim Latifi, Dorjana Beqiraj-Kalamishi, Ibrahim Mehmeti, Arben Haziri

PHYTOCHEMICAL AND IN VITRO ANTIOXIDANT STUDIES OF PRIMULA VERIS (L.) GROWING WILD IN KOSOVO

Ibrahim Rudhani, Florentina Raci, Hamide Ibrahimi, Arben Mehmeti, Ariana Kameri, Fatmir Faiku, Majlinda Daci, Sevdije Govori, Arben Haziri

ПЕДАГОГИЧЕСКА ПОЕМА

Преди година-две заедно с директора на Националното издателство „Аз- буки“ д-р Надя Кантарева-Барух посетихме няколко училища в Родопите. В едно от тях ни посрещнаха в голямата учителска стая. По стените ѝ имаше големи портрети на видни педагози, а под тях – художествено написани умни мисли, които те по някакъв повод са казали. На централно място бе портретът на Антон Семьонович Макаренко (1888 – 1939). Попитах учителките кой е Макаренко – те посрещнаха въпроса ми с мълчание. А някога, в г

Книжка 4
„СИМВОЛНИЯТ КАПИТАЛ“ НА БЪЛГАРСКОТО УЧИЛИЩЕ

Николай Цанков, Веска Гювийска

KINETICS OF PHOTO-ELECTRO-ASSISTED DEGRADATION OF REMAZOL RED 5B

Fitria Rahmawati, Tri Martini, Nina Iswati

ALLELOPATHIC AND IN VITRO ANTICANCER ACTIVITY OF STEVIA AND CHIA

Asya Dragoeva, Vanya Koleva, Zheni Stoyanova, Eli Zayova, Selime Ali

NOVEL HETEROARYLAMINO-CHROMEN-2-ONES AND THEIR ANTIBACTERIAL ACTIVITY

Ramiz Hoti, Naser Troni, Hamit Ismaili, Gjyle Mulliqi-Osmani, Veprim Thaçi

Книжка 3
Quantum Connement of Mobile Na+ Ions in Sodium Silicate Glassy

QUANTUM CONFINEMENT OF MOBILE Na + IONS, IN SODIUM SILICATE GLASSY NANOPARTICLES

OPTIMIZATION OF ENGINE OIL FORMULATION USING RESPONSE SURFACE METHODOLOGY AND GENETIC ALGORITHM: A COMPARATIVE STUDY

Behnaz Azmoon, Abolfazl Semnani, Ramin Jaberzadeh Ansari, Hamid Shakoori Langeroodi, Mahboube Shirani, Shima Ghanavati Nasab

EVALUATION OF ANTIBACTERIAL ACTIVITY OF DIFFERENT SOLVENT EXTRACTS OF TEUCRIUM CHAMAEDRYS (L.) GROWING WILD IN KOSOVO

Arben Haziri, Fatmir Faiku, Roze Berisha, Ibrahim Mehmeti, Sevdije Govori, Imer Haziri

Книжка 2
COMPUTER SIMULATORS: APPLICATION FOR GRADUATES’ADAPTATION AT OIL AND GAS REFINERIES

Irena O. Dolganova, Igor M. Dolganov, Kseniya A. Vasyuchka

SYNTHESIS OF NEW [(3-NITRO-2-OXO-2H-CHROMEN4-YLAMINO)-PHENYL]-PHENYL-TRIAZOLIDIN-4-ONES AND THEIR ANTIBACTERIAL ACTIVITY

Ramiz Hoti, Hamit Ismaili, Idriz Vehapi, Naser Troni, Gjyle Mulliqi-Osmani, Veprim Thaçi

STABILITY OF RJ-5 FUEL

Lemi Türker, Serhat Variş

A STUDY OF BEGLIKTASH MEGALITHIC COMPLEX

Diana Kjurkchieva, Evgeni Stoykov, Sabin Ivanov, Borislav Borisov, Hristo Hristov, Pencho Kyurkchiev, Dimitar Vladev, Irina Ivanova

Книжка 1
2016 година
Книжка 6
THE EFFECT OF KOH AND KCL ADDITION TO THE DESTILATION OF ETHANOL-WATER MIXTURE

Khoirina Dwi Nugrahaningtyas, Fitria Rahmawati, Avrina Kumalasari

Книжка 5

ОЦЕНЯВАНЕ ЛИЧНОСТТА НА УЧЕНИКА

Министерството на народното просвещение е направило допълне- ния към Правилника за гимназиите (ДВ, бр. 242 от 30 октомври 1941 г.), според които в бъдеще ще се оценяват следните прояви на учениците: (1) трудолюбие; (2) ред, точност и изпълнителност; (3) благовъзпитаност; (4) народностни прояви. Трудолюбието ще се оценява с бележките „образцово“, „добро“, „незадо- волително“. С „образцово“ ще се оценяват учениците, които с любов и по- стоянство извършват всяка възложена им ил

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VOLTAMMERIC SENSOR FOR NITROPHENOLS BASED ON SCREEN-PRINTED ELECTRODE MODIFIED WITH REDUCED GRAPHENE OXIDE

Arsim Maloku, Liridon S. Berisha, Granit Jashari, Eduard Andoni, Tahir Arbneshi

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ИЗСЛЕДВАНЕ НА ПРОФЕСИОНАЛНО-ПЕДАГОГИЧЕСКАТА РЕФЛЕКСИЯ НА УЧИТЕЛЯ ПО БИОЛОГИЯ (ЧАСТ ВТОРА)

Надежда Райчева, Иса Хаджиали, Наташа Цанова, Виктория Нечева

EXISTING NATURE OF SCIENCE TEACHING OF A THAI IN-SERVICE BIOLOGY TEACHER

Wimol Sumranwanich, Sitthipon Art-in, Panee Maneechom, Chokchai Yuenyong

NUTRIENT COMPOSITION OF CUCURBITA MELO GROWING IN KOSOVO

Fatmir Faiku, Arben Haziri, Fatbardh Gashi, Naser Troni

НАГРАДИТЕ „ЗЛАТНА ДЕТЕЛИНА“ ЗА 2016 Г.

На 8 март 2016 г. в голямата зала на Националния политехнически музей в София фондация „Вигория“ връчи годишните си награди – почетен плакет „Златна детелина“. Тази награда се дава за цялостна професионална и творче- ска изява на личности с особени заслуги към обществото в трите направления на фондация „Вигория“ – образование, екология, култура. Наградата цели да се даде израз на признателност за високи постижения на личности, които на професионално равнище и на доброволни начала са рабо

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СТО ГОДИНИ ОТ РОЖДЕНИЕТО НА ПРОФЕСОР ХРИСТО ИВАНОВ (1916 – 2004)

СТО ГОДИНИ ОТ РОЖДЕНИЕТО, НА ПРОФЕСОР ХРИСТО ИВАНОВ, (96 – 00

CONTEXT-BASED CHEMISTRY LAB WORK WITH THE USE OF COMPUTER-ASSISTED LEARNING SYSTEM

N. Y. Stozhko, A. V. Tchernysheva, E.M. Podshivalova, B.I. Bortnik

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ПО ПЪТЯ

Б. В. Тошев

INTERDISCIPLINARY PROJECT FOR ENHANCING STUDENTS’ INTEREST IN CHEMISTRY

Stela Georgieva, Petar Todorov , Zlatina Genova, Petia Peneva

2015 година
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COMPLEX SYSTEMS FOR DRUG TRANSPORT ACROSS CELL MEMBRANES

Nikoleta Ivanova, Yana Tsoneva, Nina Ilkova, Anela Ivanova

SURFACE FUNCTIONALIZATION OF SILICA SOL-GEL MICROPARTICLES WITH EUROPIUM COMPLEXES

Nina Danchova , Gulay Ahmed , Michael Bredol , Stoyan Gutzov

INTERFACIAL REORGANIZATION OF MOLECULAR ASSEMBLIES USED AS DRUG DELIVERY SYSTEMS

I. Panaiotov, Tz. Ivanova, K. Balashev, N. Grozev, I. Minkov, K. Mircheva

KINETICS OF THE OSMOTIC PROCESS AND THE POLARIZATION EFFECT

Boryan P. Radoev, Ivan L. Minkov, Emil D. Manev

WETTING BEHAVIOR OF A NATURAL AND A SYNTHETIC THERAPEUTIC PULMONARY SURFACTANTS

Lidia Alexandrova, Michail Nedyalkov, Dimo Platikanov

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TEACHER’S ACCEPTANCE OF STUDENTS WITH DISABILITY

Daniela Dimitrova-Radojchikj, Natasha Chichevska-Jovanova

IRANIAN UNIVERSITY STUDENTS’ PERCEPTION OF CHEMISTRY LABORATORY ENVIRONMENTS

Zahra Eskandari, Nabi.A Ebrahimi Young Researchers & Elite Club, Arsanjan Branch,

APPLICATION OF LASER INDUCED BREAKDOWN SPECTROSCOPY AS NONDESDUCTRIVE AND SAFE ANALYSIS METHOD FOR COMPOSITE SOLID PROPELLANTS

Amir Hossein Farhadian, Masoud Kavosh Tehrani, Mohammad Hossein Keshavarz, Seyyed Mohamad Reza Darbany, Mehran Karimi, Amir Hossein Rezayi Optics & Laser Science and Technology Research Center,

THE EFFECT OF DIOCTYLPHTHALATE ON INITIAL PROPERTIES AND FIELD PERFORMANCE OF SOME SEMISYNTHETIC ENGINE OILS

Azadeh Ghasemizadeh, Abolfazl Semnani, Hamid Shakoori Langeroodi, Alireza Nezamzade Ejhieh

QUALITY ASSESSMENT OF RIVER’S WATER OF LUMBARDHI PEJA (KOSOVO)

Fatmir Faiku, Arben Haziri, Fatbardh Gashi, Naser Troni

Книжка 4
БЛАГОДАРЯ ВИ!

Александър Панайотов

ТЕМАТА ВЪГЛЕХИДРАТИ В ПРОГРАМИТЕ ПО ХИМИЯ И БИОЛОГИЯ

Радка Томова, Елена Бояджиева, Миглена Славова , Мариан Николов

BILINGUAL COURSE IN BIOTECHNOLOGY: INTERDISCIPLINARY MODEL

V. Kolarski, D. Marinkova, R. Raykova, D. Danalev, S. Terzieva

ХИМИЧНИЯТ ОПИТ – НАУКА И ЗАБАВА

Елица Чорбаджийска, Величка Димитрова, Магдалена Шекерлийска, Галина Бальова, Методийка Ангелова

ЕКОЛОГИЯТА В БЪЛГАРИЯ

Здравка Костова

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SYNTHESIS OF FLUORINATED HYDROXYCINNAMOYL DERIVATIVES OF ANTI-INFLUENZA DRUGS AND THEIR BIOLOGICAL ACTIVITY

Boyka Stoykova, Maya Chochkova, Galya Ivanova, Luchia Mukova, Nadya Nikolova, Lubomira Nikolaeva-Glomb, Pavel Vojtíšek, Tsenka Milkova, Martin Štícha, David Havlíček

SYNTHESIS AND ANTIVIRAL ACTIVITY OF SOME AMINO ACIDS DERIVATIVES OF INFLUENZA VIRUS DRUGS

Radoslav Chayrov, Vesela Veselinova, Vasilka Markova, Luchia Mukova, Angel Galabov, Ivanka Stankova

NEW DERIVATIVES OF OSELTAMIVIR WITH BILE ACIDS

Kiril Chuchkov, Silvia Nakova, Lucia Mukova, Angel Galabov, Ivanka Stankova

MONOHYDROXY FLAVONES. PART III: THE MULLIKEN ANALYSIS

Maria Vakarelska-Popovska, Zhivko Velkov

LEU-ARG ANALOGUES: SYNTHESIS, IR CHARACTERIZATION AND DOCKING STUDIES

Tatyana Dzimbova, Atanas Chapkanov, Tamara Pajpanova

MODIFIED QUECHERS METHOD FOR DETERMINATION OF METHOMYL, ALDICARB, CARBOFURAN AND PROPOXUR IN LIVER

I. Stoykova, T. Yankovska-Stefenova, L.Yotova, D. Danalev Bulgarian Food Safety Agency, Sofi a, Bulgaria

LACTOBACILLUS PLANTARUM AC 11S AS A BIOCATALYST IN MICROBIAL ELECYTOLYSIS CELL

Elitsa Chorbadzhiyska, Yolina Hubenova, Sophia Yankova, Dragomir Yankov, Mario Mitov

STUDYING THE PROCESS OF DEPOSITION OF ANTIMONY WITH CALCIUM CARBONATE

K. B. Omarov, Z. B. Absat, S. K. Aldabergenova, A. B. Siyazova, N. J. Rakhimzhanova, Z. B. Sagindykova

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TEACHING CHEMISTRY AT TECHNICAL UNIVERSITY

Lilyana Nacheva-Skopalik, Milena Koleva

ФОРМИРАЩО ОЦЕНЯВАНЕ PEER INSTRUCTION С ПОМОЩТА НА PLICКERS ТЕХНОЛОГИЯТА

Ивелина Коцева, Мая Гайдарова, Галина Ненчева

VAPOR PRESSURES OF 1-BUTANOL OVER WIDE RANGE OF THEMPERATURES

Javid Safarov, Bahruz Ahmadov, Saleh Mirzayev, Astan Shahverdiyev, Egon Hassel

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РУМЕН ЛЮБОМИРОВ ДОЙЧЕВ (1938 – 1999)

Огнян Димитров, Здравка Костова

NAMING OF CHEMICAL ELEMENTS

Maria Atanassova

НАЙДЕН НАЙДЕНОВ, 1929 – 2014 СПОМЕН ЗА ПРИЯТЕЛЯ

ИНЖ. НАЙДЕН ХРИСТОВ НАЙДЕНОВ, СЕКРЕТАР, НА СЪЮЗА НА ХИМИЦИТЕ В БЪЛГАРИЯ (2.10.1929 – 25.10.2014)

2014 година
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145 ГОДИНИ БЪЛГАРСКА АКАДЕМИЯ НА НАУКИТЕ

145 ANNIVERSARY OF THE BULGARIAN ACADEMY OF SCIENCES

ПАРНО НАЛЯГАНЕ НА РАЗТВОРИ

Б. В. Тошев Българско дружество за химическо образование и история и философия на химията

LUBRICATION PROPERTIES OF DIFFERENT PENTAERYTHRITOL-OLEIC ACID REACTION PRODUCTS

Abolfazl Semnani, Hamid Shakoori Langeroodi, Mahboube Shirani

THE ORIGINS OF SECONDARY AND TERTIARY GENERAL EDUCATION IN RUSSIA: HISTORICAL VIEWS FROM THE 21ST CENTURY

V. Romanenko, G. Nikitina Academy of Information Technologies in Education, Russia

ALLELOPATHIC AND CYTOTOXIC ACTIVITY OF ORIGANUM VULGARE SSP. VULGARE GROWING WILD IN BULGARIA

Asya Pencheva Dragoeva, Vanya Petrova Koleva, Zheni Dimitrova Nanova, Mariya Zhivkova Kaschieva, Irina Rumenova Yotova

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GENDER ISSUES OF UKRAINIAN HIGHER EDUCATION

Н.H.Petruchenia, M.I.Vorovka

МНОГОВАРИАЦИОННА СТАТИСТИЧЕСКА ОЦЕНКА НА DREEM – БЪЛГАРИЯ: ВЪЗПРИЕМАНЕ НА ОБРАЗОВАТЕЛНАТА СРЕДА ОТ СТУДЕНТИТЕ В МЕДИЦИНСКИЯ УНИВЕРСИТЕТ – СОФИЯ

Радка Томова, Павлина Гатева, Радка Хаджиолова, Зафер Сабит, Миглена Славова, Гергана Чергарова, Васил Симеонов

MUSSEL BIOADHESIVES: A TOP LESSON FROM NATURE

Saâd Moulay Université Saâd Dahlab de Blida, Algeria

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ЕЛЕКТРОННО ПОМАГАЛO „ОТ АТОМА ДО КОСМОСА“ ЗА УЧЕНИЦИ ОТ Х КЛАС

Силвия Боянова Професионална гимназия „Акад. Сергей П. Корольов“ – Дупница

ЕСЕТО КАТО ИНТЕГРАТИВЕН КОНСТРУКТ – НОРМАТИВЕН, ПРОЦЕСУАЛЕН И ОЦЕНЪЧНО-РЕЗУЛТАТИВЕН АСПЕКТ

Надежда Райчева, Иван Капурдов, Наташа Цанова, Иса Хаджиали, Снежана Томова

44

Донка Ташева, Пенка Василева

ДОЦ. Д.П.Н. АЛЕКСАНДЪР АТАНАСОВ ПАНАЙОТОВ

Наташа Цанова, Иса Хаджиали, Надежда Райчева

COMPUTER ASSISTED LEARNING SYSTEM FOR STUDYING ANALYTICAL CHEMISTRY

N. Y. Stozhko, A. V. Tchernysheva, L.I. Mironova

С РАКЕТНА ГРАНАТА КЪМ МЕСЕЦА: БОРБА С ЕДНА ЛЕДЕНА ЕПОХА В ГОДИНАТА 3000 СЛЕД ХРИСТА. 3.

С РАКЕТНА ГРАНАТА КЪМ МЕСЕЦА:, БОРБА С ЕДНА ЛЕДЕНА ЕПОХА, В ГОДИНАТА 000 СЛЕД ХРИСТА. .

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KNOWLEDGE OF AND ATTITUDES TOWARDS WATER IN 5

Antoaneta Angelacheva, Kalina Kamarska

ВИСША МАТЕМАТИКА ЗА УЧИТЕЛИ, УЧЕНИЦИ И СТУДЕНТИ: ДИФЕРЕНЦИАЛНО СМЯТАНЕ

Б. В. Тошев Българско дружество за химическо образование и история и философия на химията

ВАСИЛ ХРИСТОВ БОЗАРОВ

Пенка Бозарова, Здравка Костова

БИБЛИОГРАФИЯ НА СТАТИИ ЗА МИСКОНЦЕПЦИИТЕ В ОБУЧЕНИЕТО ПО ПРИРОДНИ НАУКИ ВЪВ ВСИЧКИ ОБРАЗОВАТЕЛНИ НИВА

Б. В. Тошев Българско дружество за химическо образование и история и философия на химията

Книжка 2
SCIENTIX – OБЩНОСТ ЗА НАУЧНО ОБРАЗОВАНИЕ В ЕВРОПА

Свежина Димитрова Народна астрономическа обсерватория и планетариум „Николай Коперник“ – Варна

BOTYU ATANASSOV BOTEV

Zdravka Kostova, Margarita Topashka-Ancheva

CHRONOLOGY OF CHEMICAL ELEMENTS DISCOVERIES

Maria Atanassova, Radoslav Angelov

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ОБРАЗОВАНИЕ ЗА ПРИРОДОНАУЧНА ГРАМОТНОСТ

Адриана Тафрова-Григорова

A COMMENTARY ON THE GENERATION OF AUDIENCE-ORIENTED EDUCATIONAL PARADIGMS IN NUCLEAR PHYSICS

Baldomero Herrera-González Universidad Autónoma del Estado de México, Mexico

2013 година
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DIFFERENTIAL TEACHING IN SCHOOL SCIENCE EDUCATION: CONCEPTUAL PRINCIPLES

G. Yuzbasheva Kherson Academy of Continuing Education, Ukraine

АНАЛИЗ НА ПОСТИЖЕНИЯТА НА УЧЕНИЦИТЕ ОТ ШЕСТИ КЛАС ВЪРХУ РАЗДЕЛ „ВЕЩЕСТВА И ТЕХНИТЕ СВОЙСТВА“ ПО „ЧОВЕКЪТ И ПРИРОДАТА“

Иваничка Буровска, Стефан Цаковски Регионален инспекторат по образованието – Ловеч

HISTORY AND PHILOSOPHY OF SCIENCE: SOME RECENT PERIODICALS (2013)

Chemistry: Bulgarian Journal of Science Education

45. НАЦИОНАЛНА КОНФЕРЕНЦИЯ НА УЧИТЕЛИТЕ ПО ХИМИЯ

„Образователни стандарти и природонаучна грамотност“ – това е темата на състоялата се от 25 до 27 октомври 2013 г. в Габрово 45. Национална конфе- ренция на учителите по химия с международно участие, която по традиция се проведе комбинирано с Годишната конференция на Българското дружество за химическо образование и история и философия на химията. Изборът на темата е предизвикан от факта, че развиването на природонаучна грамотност е обща тенденция на реформите на учебните програми и главна

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ЗА ХИМИЯТА НА БИРАТА

Ивелин Кулев

МЕТЕОРИТЪТ ОТ БЕЛОГРАДЧИК

Б. В. Тошев Българско дружество за химическо образование и история и философия на химията

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RECASTING THE DERIVATION OF THE CLAPEYRON EQUATION INTO A CONCEPTUALLY SIMPLER FORM

Srihari Murthy Meenakshi Sundararajan Engineering College, India

CHEMICAL REACTIONS DO NOT ALWAYS MODERATE CHANGES IN CONCENTRATION OF AN ACTIVE COMPONENT

Joan J. Solaz-Portolés, Vicent Sanjosé Universitat de Valènciа, Spain

POLYMETALLIC COMPEXES: CV. SYNTHESIS, SPECTRAL, THERMOGRAVIMETRIC, XRD, MOLECULAR MODELLING AND POTENTIAL ANTIBACTERIAL PROPERTIES OF TETRAMERIC COMPLEXES OF Co(II), Ni(II), Cu(II), Zn(II), Cd(II) AND Hg(II) WITH OCTADENTATE AZODYE LIGANDS

Bipin B. Mahapatra, S. N. Dehury, A. K. Sarangi, S. N. Chaulia G. M. Autonomous College, India Covt. College of Engineering Kalahandi, India DAV Junior College, India

ПРОФЕСОР ЕЛЕНА КИРКОВА НАВЪРШИ 90 ГОДИНИ

CELEBRATING 90TH ANNIVERSARY OF PROFESSOR ELENA KIRKOVA

Книжка 3
SIMULATION OF THE FATTY ACID SYNTHASE COMPLEX MECHANISM OF ACTION

M.E.A. Mohammed, Ali Abeer, Fatima Elsamani, O.M. Elsheikh, Abdulrizak Hodow, O. Khamis Haji

FORMING OF CONTENT OF DIFFERENTIAL TEACHING OF CHEMISTRY IN SCHOOL EDUCATION OF UKRAINE

G. Yuzbasheva Kherson Academy of Continuing Education, Ukraine

ИЗСЛЕДВАНЕ НА РАДИКАЛ-УЛАВЯЩА СПОСОБНОСТ

Станислав Станимиров, Живко Велков

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Книжка 1
COLORFUL EXPERIMENTS FOR STUDENTS: SYNTHESIS OF INDIGO AND DERIVATIVES

Vanessa BIANDA, Jos-Antonio CONSTENLA, Rolf HAUBRICHS, Pierre-Lonard ZAFFALON

OBSERVING CHANGE IN POTASSIUM ABUNDANCE IN A SOIL EROSION EXPERIMENT WITH FIELD INFRARED SPECTROSCOPY

Mila Ivanova Luleva, Harald van der Werff, Freek van der Meer, Victor Jetten

ЦАРСКАТА ПЕЩЕРА

Рафаил ПОПОВ

УЧИЛИЩНИ ЛАБОРАТОРИИ И ОБОРУДВАНЕ SCHOOL LABORATORIES AND EQUIPMENT

Учебни лаборатории Илюстрации от каталог на Franz Hugershoff, Лайциг, притежаван от бъдещия

2012 година
Книжка 6
ADDRESING STUDENTS’ MISCONCEPTIONS CONCERNING CHEMICAL REACTIONS AND SYMBOLIC REPRESENTATIONS

Marina I. Stojanovska, Vladimir M. Petruševski, Bojan T. Šoptrajanov

АНАЛИЗ НА ПОСТИЖЕНИЯТА НА УЧЕНИЦИТЕ ОТ ПЕТИ КЛАС ВЪРХУ РАЗДЕЛ „ВЕЩЕСТВА И ТЕХНИТЕ СВОЙСТВА“ ПО ЧОВЕКЪТ И ПРИРОДАТА

Иваничка Буровска, Стефан Цаковски Регионален инспекторат по образованието – Ловеч

ЕКОТОКСИКОЛОГИЯ

Васил Симеонов

ПРОФ. МЕДОДИЙ ПОПОВ ЗА НАУКАТА И НАУЧНАТА ДЕЙНОСТ (1920 Г.)

Проф. Методий Попов (1881-1954) Госпожици и Господа студенти,

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КОНЦЕПТУАЛНА СХЕМА НА УЧИЛИЩНИЯ КУРС П О ХИМИЯ – МАКР О СКОПСКИ ПОДХОД

Б. В. Тошев Българско дружество за химическо образование и история и философия на химията

ROLE OF ULTRASONIC WAVES TO STUDY MOLECULAR INTERACTIONS IN AQUEOUS SOLUTION OF DICLOFENAC SODIUM

Sunanda S. Aswale, Shashikant R. Aswale, Aparna B. Dhote Lokmanya Tilak Mahavidyalaya, INDIA Nilkanthrao Shinde College, INDIA

SIMULTANEOUS ESTIMATION OF IBUPROFEN AND RANITIDINE HYDROCHLORIDE USING UV SPECTROPHOT O METRIC METHOD

Jadupati Malakar, Amit Kumar Nayak Bengal College of Pharmaceutical Sciences and Research, INDIA

GAPS AND OPPORTUNITIES IN THE USE OF REMOTE SENSING FOR SOIL EROSION ASSESSMENT

Mila Ivanova Luleva, Harald van der Werff, Freek van der Meer, Victor Jetten

РАДИОХИМИЯ И АРХЕОМЕТРИЯ: ПРО Ф. ДХН ИВЕЛИН КУЛЕВ RADIOCHEMISTRY AND ARCHEOMETRY: PROF. IVELIN KULEFF, DSc

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TEACHING THE CONSTITUTION OF MATTER

Małgorzata Nodzyńska, Jan Rajmund Paśko

СЪСИРВАЩА СИСТЕМА НА КРЪВТА

Маша Радославова, Ася Драгоева

CATALITIC VOLCANO

CATALITIC VOLCANO

43-ТА МЕЖДУНАРОДНА ОЛИМПИАДА ПО ХИМИЯ

Донка ТАШЕВА, Пенка ЦАНОВА

ЮБИЛЕЙ: ПРОФ. ДХН БОРИС ГЪЛЪБОВ JUBILEE: PROF. DR. BORIS GALABOV

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ПЪРВИЯТ ПРАВИЛНИК ЗА УЧЕБНИЦИТЕ (1897 Г.)

Чл. 1. Съставянето и издаване на учебници се предоставя на частната инициа- тива. Забележка: На учителите – съставители на учебници се запрещава сами да разпродават своите учебници. Чл. 2. Министерството на народното просвещение може да определя премии по конкурс за съставяне на учебници за горните класове на гимназиите и специ- алните училища. Чл. 3. Никой учебник не може да бъде въведен в училищата, ако предварително не е прегледан и одобрен от Министерството на народното просвещение. Чл.

JOHN DEWEY: HOW WE THINK (1910)

John Dewey (1859 – 1952)

ИНФОРМАЦИЯ ЗА СПЕЦИАЛНОСТИТЕ В ОБЛАСТТА НА ПРИРОДНИТЕ НАУКИ В СОФИЙСКИЯ УНИВЕРСИТЕТ „СВ. КЛИМЕНТ ОХРИДСКИ“ БИОЛОГИЧЕСКИ ФАКУЛТЕТ

1. Биология Студентите от специалност Биология придобиват знания и практически умения в областта на биологическите науки, като акцентът е поставен на организмово равнище. Те се подготвят да изследват биологията на организмите на клетъчно- организмово, популационно и екосистемно ниво в научно-функционален и прило- жен аспект, с оглед на провеждане на научно-изследователска, научно-приложна, производствена и педагогическа дейност. Чрез широк набор избираеми и факул- тативни курсове студентите

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УЧИТЕЛИТЕ ПО ПРИРОДНИ НАУКИ – ЗА КОНСТРУКТИВИСТКАТА УЧЕБНА СРЕДА В БЪЛГАРСКОТО УЧИЛИЩЕ

Адриана Тафрова-Григорова, Милена Кирова, Елена Бояджиева

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Людмила Генкова, Свобода Бенева Българско дружество за химическо образование и история и философия на химията

НАЧАЛО НА ПРЕПОДАВАНЕТО НА УЧЕБЕН ПРЕДМЕТ ХИМИЯ В АПРИЛОВОТО УЧИЛИЩЕ В ГАБРОВО

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В един дълъг период от време гимназиалните учители по математика, физика, химия и естествена

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„МАГИЯТА НА ХИМИЯТА“ – ВЕЧЕР НА ХИМИЯТА В ЕЗИКОВА ГИМНАЗИЯ „АКАД. Л. СТОЯНОВ“ БЛАГОЕВГРАД

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Бурният развой на естествознанието във всичките му клонове през XIX –ия век предизвика дълбоки промени в мирогледа на културния свят, в техниката и в индустрията, в социалните отношения и в държавните интереси. Можем ли днес да си представим един философ, един държавен мъж, един обществен деец, един индустриалец, просто един културен човек, който би могъл да игнорира придобив- ките на природните науки през последния век. Какви ужасни катастрофи, какви социални сътресения би сполетяло съвре

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MURPHY’S LAW IN CHEMISTRY

Milan D. Stojković

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Семейството трябва да познава училишето и училишето трябва да познава семейството. Взаимното познанство се налага от обстоятелството, че те, макар и да са два различни по природата си фактори на възпитанието, преследват една и съща проста цел – младото поколение да бъде по-умно, по-нравствено, физически по-здраво и по-щастливо от старото – децата да бъдат по-щастливи от родителите