Обучение по природни науки и върхови технологии

2017/3, стр. 420 - 430

CHEMOMETRICASSISTEDSPECTROPHOTOMETRIC ESTIMATION OF LANSOPRAZOLE AND DOMEPERIDONE IN BULK AND COMMERCIAL DOSAGE FORM

Farheen Sami
Universiti Kuala Lumpur Royal College of Medicine Perak – Malaysia
Shahnaz Majeed
Universiti Kuala Lumpur Royal College of Medicine Perak – Malaysia
Tengku Azlan Shah Tengku Mohammed
Universiti Kuala Lumpur Royal College of Medicine Perak – Malaysia
Noor Fatin Amalina Kamaruddin
Universiti Kuala Lumpur Royal College of Medicine Perak – Malaysia
Mohammad Zulhimi Atan
Universiti Kuala Lumpur Royal College of Medicine Perak – Malaysia
Syed Amir Javid Bukhari
Institute of Pharmaceutical & Applied Science – India
Namra
Institute of Pharmaceutical & Applied Science – India
Bushra Hasan
Jamia Millia Islamia University – India
Mohammed Tahir Ansari
E-mail: md.a.tahir@gmail.com
Research Laboratory
Faculty of Pharmacy and Health Sciences
Universiti Kuala Lumpur Royal College of Medicine Perak (UniKL-RCMP)
No 3 Jalan Greentown
30450 Ipoh
Perak Malaysia

Резюме: Chemometric calibrations namely, Partial least square (PLS), principal component regression (PCR) and classical least square (CLS), were developed for the simultaneous determination of domeperidone and lansoprazole from combined pharmaceutical dosage forms. In these methods with chemometric techniques, the calibrations were constructed by using the absorption data matrix, with measurements in the range of 260-310 nm (Δλ = 1 nm) in their zero order spectra. The chemometric calibrations were realized by using R – software (version 2.1.1). The linearity range was found to be 4-36 µg ml\(^{-1}\) and 2-18 µgml\(^{-1}\) for DOMP and LANS respectively. The lower correlation coefficient values 0.9998, 0.9999 and 0.9992 for DOMP and 0.996, 0.998 and 0.999 for LANS respectively estimated for CLS, PCR and PLS respectively. The validity of the proposed methods was successfully assessed for analysis of both drugs in laboratory prepared mixtures and in commercial formulations.

Ключови думи: domperidone; lansoprazole; chemometric; R–software; validation; statistical parameters; standard addition

Introduction

Lansoprazole (LZP) is used in the treatment of acid reflux. It impedes the gastric glands from supplementing gastric acid. LZP has also witnessed its role in suppressing the action of Helicobacter pylori. Study suggest that LZP is metabolized to an active sulfonamide metabolite which constrains the activity of the sulfhydryl group and curtails the hydrogen ion concentration (Alai & Lin, 2015; Baldi, 2005; Matheson & Jarvis, 2001). Domperidone (DMP) is used as a prominent antiemetic drug. DMP curtails esophageal sphincter pressure thereby intensifying esophageal and gastric peristalsis which ameliorates gastric emptying. Absorption of the drug is characterized by active transport from the upper part of the gastrointestinal tract (GIT) including stomach (Arora et al., 2011; Tripathi, 2013). LZP and DMP estimation has been assisted by many techniques such as ultraviolet visible method (Anil Kumar et al., 2012; Sherje et al., 2008), High Performance Liquid Chromatography (HPLC) (Janardhanan et al., 2011), High Performance Thin Liquid Chromatography (HPTLC) (Aanandhi et al., 2009; Susheel et al., 2007) and ion-pair complex formation reaction (Devi et al., 2013).

However, available methods were of either of high cost or found to be insensitive and invalidated since the result was composed of effective information and ineffective noise. Studies have suggested that instrumental analysis sequined with statistical method such as chemometrics augments the signal-tonoise ratio, optimize exploratory conditions, improve selectivity of determination and raise analytical operation efficiency. The approach is useful in simultaneous determination of two or more components in pharmaceutical dosage form with overlapping spectra (Deming et al.,1988; Kumar et al., 2014; Marwada et al., 2014). Classical Least Squares (CLS), Principal Components Regression (PCR) and Partial Least Square (PLS) are the most fundamental multivariate methods that can calibrate and validate analytical methods (Khajehsharifi et al., 2017; Salem et al., 2002).

Material and mathods

Pure drug samples of Domperidone (DMP) and Lansoprazole (LZP) were procured from sigma-aldrich, Malaysia. The drugs were used without further purification. All the other reagents and solvents were procured as HPLC grade. A Formulated Mixture (FM) of LZP and DMP (30 mg LZP and 10 mg DMP) was used as a commercial dosage form for analysis.

Standard solutions of Domperidone and Lansoprazole

Standard solution of DMP and LZP with of suitable concentrations were formulated in methanolic sodium hydroxide respectively (\(80: 20 \mathrm{v} / \mathrm{v}\) ). Powder equivalent to 10 FM were weighed and mixed for further analysis. Powder equivalent to one unit of capsule was triturated, dissolved and sonicated for 10 minutes in 100 ml methanolic sodium hydroxide. This solution was suitably diluted with methanolic sodium hydroxide. The concentration of each component in the mixture was accurately resoluted by chemometric assisted spectrophotometric method. Perkin Elmer lambda 35 double beam UV Visible spectrophotometer assisted with UV winlab software was used for spectrophotometric measurements. The resulting data was realized chemometrically using R – software environment.

Calibration sets

Sequential calibration of 9 dilutions each for DMP (\(5-80 \mu \mathrm{~g} \mathrm{ml}^{-1}\) ) and LZP (\(5-25\) \(\mu \mathrm{g} . \mathrm{ml}^{-1}\) ) was prepared in methanolic sodium hydroxide solution. The solution was scanned in the wavelength range of \(200-400 \mathrm{~nm}\).

Multilevel factorial design of DMP and LZP

Multilevel multi factorial design of five level concentrations for DMP and LZP within the stated range were introduced. The developed method needs proper validation for its application. The studies were performed for validation purpose in compliance with ICH guidelines (Beg et al., 2012; Hasnain et al., 2013; 2017).

Statistical parameter

The most general expression for calibration model in chemometric method is the Standard Error of Calibration (SEC) and Standard Error of Prediction (SEP). It can be expressed as the following equation:

\[ S E P(S E C)=\tfrac{\sqrt{\sum_{i=1}^{N}\left(\text { Conc }_{i}^{\text {Added }}-\text { Conc }_{i}^{\text {Found }}\right)^{2}}}{n} \]

Here, \(\mathrm{n}=\) number of the calibrated mixtures, = added concentration of DOM and LZP, and predicted concentration of DOM and LZP. The values for SEP are quoted in Table 1.

Calibration spectra were recorded using 25 sets of solution (Table 2). Predicted concentration of LZP and DMP was compared with the actual concentration of each sample of the calibration mixtures. Mean Squares Error of Prediction (MSEP) (Fig 1 A and B, Fig 2 A and B) and Prediction Error Sum of Squares (PRESS) were computed (Table 3).

Linearity

For linearity five replicates of measurement were performed in each concentration. It was established that absorbance and concentration behave linearly at concentration range of \(5-80 \mu \mathrm{~g} / \mathrm{ml}\) for DMP and \(5-25 \mu \mathrm{~g} / \mathrm{ml}\) for LZP.

Table 1. Statistical parameters of chemometric methods in calibration step of Zero-order spectra

ComponentCLSPCRPLSSECSECPRESSRSEa(%) SECPRESSRSE(%) DMP0.66520.01400.00470.06540.01520.00560.0713LMP0.38610.01710.00700.15990.01990.00950.1857

\({ }^{\text {a }}\) Relative standard error of calibration of single component

Table 2. Composition of the concentration (calibration) set

Mixture No. Concentration (µg ml-1) DMPLMP15521053205440558056510710108201094010108010115151210151320151440151580151652017102018202019402020802021525221025232025244025258025

Table 3. Statistical parameters of chemometric methods in prediction step of Zero-order spectra

ComponentDMPLMPCLSSEP0.99060.8009A0.18100.3628B1.03350.9745R0.99840.9968PCRSEP0.35240.4562A0.10330.2318B0.99380.9820R0.99960.9996PLSSEP0.36380.4657a0.11330.2485b0.98870.9826r0.99960.9996a, Intercept;b, slope;r, correlation coecient

Figure 1. MSEP plots of a calibration set obtained using leave-one- out cross validation of PLS-model for DMP (A) and LZP (B) in UV absorption data

Figure 2. MSEP plots of a calibration set obtained using leave-one- out cross validation of PCR-model for DMP (A) and LZP (B) in UV absorption data

Precision

Precision is well required for any method validation and here it was determined by repeatability measurement and intermediate precision study. The measurement of absorbance was done by performing six replicates of measurement of same using a sample solution. Precision determined in terms of repeatability and intermediate precision studies were expressed as Relative Standard Deviation (RSD) of the absorbance.

Accuracy

For accuracy, standard addition method was used. The measurement of absorbance was done by performing six replicates of measurement of same using a sample solution. Percentage recovery and %RSD values connoted the accuracy of the method.

Limit of detection (LOD) and limit of quantification (LOQ)

The LOD and LOQ were estimated by plotting slope of the calibration curve of drugs and standard deviation of the y-intercept and. LOD and LOQ were analyzed by the following:

LOQ \(=10 \alpha / \mathrm{S} ;\) LOD \(=3 \alpha / \mathrm{S}[\alpha=\) standard deviation of y-intercept; S= slope of the standard curve].

Robustness

This parameter is essential to detect the effect on absorbance in terms of deliberate variation in the method parameter like wavelength (\(\lambda 1\) ), pH. The calculation of robustness is based on relative standard deviation of each parameter.

Results and discussion

A highly astute and constructive was designed for concurrent analytical estimation DMP and LZP in commercial dosage form using UV-spectrophotometer. Suitable calibrated dilutions each of DMP (\(5-80 \mu \mathrm{~g} \mathrm{ml}^{-1}\) ) and LZP \(\left(5-25 \mu \mathrm{~g} \mathrm{ml}^{-1}\right)\) in methanolic sodium hydroxide solution (\(80: 20 \mathrm{v} / \mathrm{v}\) ) was prepared and spectra was analyzed from \(200-350 \mathrm{~nm}\). Absorbance was recorded at an interval of 1 nm and \(\lambda_{\text {max }}\) were proximated to be 294 nm for the DMP and 287 nm LZP in methanolic sodium hydroxide solution (\(80: 20 \mathrm{v} / \mathrm{v}\) ). The data was processed using R-software environment. PLS, PCR and CLS algorithms were amalgamated with the recorded matrix of absorption data for all binary calibrated mixtures to actuate and design the equations. DMP exhibOptimization and selection of method parameters

Figure 3. Zero order overlay absorption spectra of standard dilution for DMP (a) and LZP (b)

Methanolic sodium hydroxide solution (\(80: 20 \mathrm{v} / \mathrm{v}\) ) was selected as solvent, Zero amplitude was observed for DMP at 280nm and LZP exhibited first derivative spec

tra at 294 nm Similarly, Zero amplitude was observed for LZP at 290nm and DMP exhibited first derivative spectra at 287 nm.

Linearity and range

The proposed chemometric assisted UV spectrophotometric method for determination of DMP and LZP showed substantial linearity in the concentration range of 5 to \(80 \mu \mathrm{gml}^{-1}\) for DMP and 5 to \(25 \mu \mathrm{gml}^{-1}\) for LZP. The correlation co-efficient following CLS, PCR and PLS method was \(0.9998,0.9999\) and 0.9992 for DMP and 0.996, 0.998 and 0.999 for LZP respectively.

Precision

Inter and intraday precision for estimation of DMP and LZP were evaluated in terms of % RSD. The binary mixtures of DMP and LZP at five levels within their linearity range were analyzed thrice (repeatability) per day for 3 different days (intermediate precision). The average % RSD of repeatability as CLS, PCR and PLS for DMP was found to be \(1.0850,0.7264, \& 1.015\) while \(1.0025,0.4156,0.8274\) for LZP respectively. The average % RSD of intermediate precision for determination of DMP and LZP was found to be \(1.2162 \%, 1.0462,0.5634\) and \(1.0874,0.9016\), & \(0.7371 \%\) respectively. The values confirm the precision of the method.

Accuracy

Proposed method was examined for its selectivity and accuracy by calculating % RSD and mean percentage recovery from five different replicates having concentrations of \(10 \mu \mathrm{~g} / \mathrm{ml}\) for DMP and \(20 \mu \mathrm{~g} / \mathrm{ml}\) for LZP. The recovery as CLS, PCR and PLS of the DMP was found to be \(98.7 \%, 100.8 \%\) & \(101.4 \%\) while \(101.2 \%\), 100.2% & 99.6% for LZP respectively and %RSD for DMP & LZP was found to be \(0.55-0.98 \%\) and \(0.35-0.87 \%\) respectively which satisfies the acceptance criteria of the study and envisages that selectivity of the method.

LOQ and LOD

The LOQ and LOD were estimated following ICH recommendations. LOQ and LOD were found to be \(0.01735 \mu \mathrm{~g} \mathrm{ml}^{-1}\) and \(0.04273 \mu \mathrm{~g} \mathrm{ml}^{-1}\) for DMP and 0.00584 \(\mu \mathrm{g} \mathrm{ml}^{-1}\) and \(0.01974 \mu \mathrm{~g} \mathrm{ml}^{-1}\) for LZP respectively.

Robustness

Double-beam UV-Vis spectrophotometer perkin elmer (Lambda 35 and 25) were used for robustness. The digital absorbance recorded by Lamda 35 and 25 exhibited negligible difference which signifies the robustness of the calibrated method for the estimation of DMP and LZP. The solutions used solvents in the estimation exhibited negligible absorbance changes for 8 hrs stored at ambient temperature.

Results of analysis of formulated mixture

The values of % recovery of formulated binary mixture as CLS, PCR and PLS of the DMP was found to be \(98.7 \%, 100.8 \%\) & \(101.4 \%\) while \(101.2 \%, 100.2 \%\) & \(99.6 \%\) for LZP respectively. The study ensured that the method is applicable for simultaneous determination DMP and LZP from their binary mixture formulation.

Conclusion

The research work validated a simple and astute analytical method for estimation of DMP and LZP in commercial formulation duly facilitated by chemometric techniques utilizing PLS, CLS and PCR. The lower correlation coefficient following CLS, PCR and PLS methods were calculated as \(0.9998,0.9999\) and 0.9992 for DMP and \(0.996,0.998\) and 0.999 for LZP respectively. The values was expected due to low concentration differences in these techniques. Withal, further additions of known amount of DMP and LZP revealed negligible changes in the recorded spectra. The results expressed reliable congruency in the examined methods of the formulated binary mixture.

The prudent results justify analytical application for developed method of simultaneous determination of LZP and DMP in the commercial formulation The proposed methods supersede other premium but protracted and costly techniques like HPLC, HPTLC, Mass spectroscopy, NMR etc.

Acknowledgements: The authors wish to acknowledge Faculty of Pharmacy and Health Sciences, Universiti Kuala Lumpur Royal College of Medicine Perak for providing necessary facilities for the research.

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Morteza Karami, Fardis Fathizadeh, Arash Yadollahi, Mehran Aboozari, Yaser Rahimian, Reza Alipoor Filabadi

КАЛЦИЙ, ФОСФОР И ДРУГИ ФАКТОРИ ЗА КОСТНО ЗДРАВЕ

Радка Томова, Светла Асенова, Павлина Косева

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THE DAY OF THE INDUCTANCE: PROBLEMS OF THE 7\(^{TH}\) EXPERIMENTAL PHYSICS OLYMPIAD, SKOPJE, 2019

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МОЛЕКУЛИТЕ НА УДОВОЛСТВИЕТО

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WATER PURIFICATION WITH LASER RADIATION

Lyubomir Lazov, Hristina Deneva, Galina Gencheva

2019 година
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LASER MICRO-PERFORATION AND FIELDS OF APPLICATION

Hristina Deneva, Lyubomir Lazov, Edmunds Teirumnieks

ПРИЛОЖНА ФОТОНИКА И АНТИОКСИДАНТНИ СВОЙСТВА НА ВИСОКООЛЕИНОВО СЛЪНЧОГЛЕДОВО МАСЛО С БИЛКОВИ ПРИМЕСИ

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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

2019 − THE INTERNATIONAL YEAR OF THE PERIODIC TABLE OF CHEMICAL ELEMENTS

Maria Atanassova, Radoslav Angelov, Dessislava Gerginova, Alexander Zahariev

ТЕХНОЛОГИЯ

Б. В. Тошев

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ЗЕЛЕНА ХИМИЯ В УЧИЛИЩНАТА ЛАБОРАТОРИЯ

Александрия Генджова, Мая Тавлинова-Кирилова, Александра Камушева

ON THE GENETIC TIES BETWEEN EUROPEAN NATIONS

Jordan Tabov, Nevena Sabeva-Koleva, Georgi Gachev

CAN BRING PEOPLE TOGETHER

Nadya Kantareva-Baruh

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CHEMOMETRIC ANALYSIS OF SCHOOL LIFE IN VARNA

Radka Tomova, Petinka Galcheva, Ivajlo Trajkov, Antoaneta Hineva, Stela Grigorova, Rumyana Slavova, 6Miglena Slavova

ЦИКЛИТЕ НА КРЕБС

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ПРИНЦИПИТЕ НА КАРИЕРНОТО РАЗВИТИЕ НА МЛАДИЯ УЧЕН

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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

A TALE OF SEVEN SCIENTISTS

Savina Kirilova

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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

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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
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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

ELECTROCHEMICAL IMPEDANCE STUDY OF BSCCO (2212) CUPRATE CERAMIC ADDITIVE TO THE ZINC ELECTRODE IN Ni-Zn BATTERIES

A. Vasev, P. Lilov, G. Ivanova, Y. Marinov, A. Stoyanova, V. Mikli, A. Stoyanova-Ivanova

CALIBRATION OF GC/MS METHOD FOR DETERMINATION OF PHTHALATES

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

SONOCHEMICAL SYNTHESIS OF 4-AMINOANTIPYRINE SCHIFF BASES A ND EVALUATION OF THEIR ANTIMICROBIAL, ANTI-TYROSINASE AND DPPH SCAVENGING ACTIVITIES

Maya Chochkova, Boyka Stoykova, Iva Romanova, Petranka Petrova, Iva Tsvetkova, Hristo Najdenski, Lubomira Nikolaeva- Glomb, Nadya Nikolova, Galya Ivanova, Atanas Chapkanov, Tsenka Milkova, Martin Štícha, Ivan Nemec

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

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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

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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

СРАВНИТЕЛЕН АНАЛИЗ НА СЪДЪРЖАЩИТЕ СЕ ЕСТЕСТВЕНИ РАДИОНУКЛИДИ В НЕВЕН И ЛАЙКА

Сияна Димова, Цветелина Стефанова, Йорданка Енева, Нина Архангелова

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

И. Милкова-Томова, Д. Бухалова, К. Николова, И. 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

ЕКСПЕРИМЕНТЪТ ПО ПРИЛОЖНА ФИЗИКА И НЕГОВАТА РОЛЯ ПРИ УСВОЯВАНЕТО НА ПРАКТИКО-ПРИЛОЖНИТЕ ЗНАНИЯ ОТ КУРСАНТИТЕ И СТУДЕНТИТЕ

Николай Тодоров Долчинков, Бонка Енчева Караиванова-Долчинкова, Nikolay Dolchinkov, Bonka Karaivanova-Dolchinkova

ЕЛЕКТРИЧНИ СВОЙСТВА НА КОМПОЗИТНИ ФИЛМИ ОТ ПОЛИМЛЕЧНА КИСЕЛИНА

Ася Виранева, Иван Бодуров, Теменужка Йовчева

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PHYSICS IS AN EVER YOUNG SCIENCE

Temenuzhka Yovcheva

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

ТЪМНАТА МАТЕРИЯ В КЛАСНАТА СТАЯ

Симона Стоянова, Анета 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

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АДАПТИРАНЕ НА ОБРАЗОВАНИЕТО ДНЕС ЗА УТРЕШНИЯ ДЕН

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

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

Veselina Kolarski, Dancho Danalev, Senia Terzieva

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ZAGREB CONNECTION INDICES OF \(\mathrm{TiO}_{2}\) 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
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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

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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

SYNTHESIS OF TiO 2-M (Cd, Co, Mn) AS A PHOTOCATALYST DEGRADATION OF METHYLENE BLUE DYE

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 <i>IN VITRO</i> ANTIOXIDANT STUDIES OF <i>PRIMULA VERIS</i> (L.) GROWING WILD IN KOSOVO

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

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„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

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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

CHEMOMETRICASSISTEDSPECTROPHOTOMETRIC ESTIMATION OF LANSOPRAZOLE AND DOMEPERIDONE IN BULK AND COMMERCIAL DOSAGE FORM

Farheen Sami, Shahnaz Majeed, Tengku Azlan Shah Tengku Mohammed, Noor Fatin Amalina Kamaruddin, Mohammad Zulhimi Atan, Syed Amir Javid Bukhari, Namra, Bushra Hasan, Mohammed Tahir Ansari

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

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

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ПРИРОДОНАУЧНАТА ГРАМОТНОСТ НА УЧЕНИЦИТЕ В НАЧАЛОТО НА XXI ВЕК – В ТЪРСЕНЕ НА КОНЦЕПТУАЛНО ЕДИНСТВО

Теодора Коларова, Иса Хаджиали, Мимия Докова, Веселин Александров

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

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

Khoirina Dwi Nugrahaningtyas, Fitria Rahmawati, Avrina Kumalasari

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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

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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 ON THE ROAD

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

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

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

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БЛАГОДАРЯ ВИ!

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ТЕМАТА ВЪГЛЕХИДРАТИ В ПРОГРАМИТЕ ПО ХИМИЯ И БИОЛОГИЯ

Радка Томова, Елена Бояджиева, Миглена Славова, Мариан Николов

BILINGUAL COURSE IN BIOTECHNOLOGY: INTERDISCIPLINARY MODEL1)

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

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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

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

Книжка 2
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

Книжка 1
РУМЕН ЛЮБОМИРОВ ДОЙЧЕВ (1938 – 1999)

Огнян Димитров, Здравка Костова

NAMING OF CHEMICAL ELEMENTS

Maria Atanassova

2014 година
Книжка 6
LUBRICATION PROPERTIES OF DIFFERENT PENTAERYTHRITOL-OLEIC ACID REACTION PRODUCTS

Abolfazl Semnani, Hamid Shakoori Langeroodi, Mahboube Shirani

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

Книжка 5
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

Книжка 4
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<sup>-ТA</sup> МЕЖДУНАРОДНА ОЛИМПИАДА ПО ХИМИЯ

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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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

ЖИВАТА ПРИРОДА

Б. В. Тошев

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
BOTYU ATANASSOV BOTEV

Zdravka Kostova, Margarita Topashka-Ancheva

CHRONOLOGY OF CHEMICAL ELEMENTS DISCOVERIES

Maria Atanassova, Radoslav Angelov

Книжка 1
КАК ДА МОТИВИРАМЕ УЧЕНИЦИТЕ OT VII КЛАС ДА УЧАТ

Маргарита Бозова, Петко Бозов

ОБРАЗОВАНИЕ ЗА ПРИРОДОНАУЧНА ГРАМОТНОСТ

Адриана Тафрова-Григорова

2013 година
Книжка 6
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

Книжка 5

ЗА ХИМИЯТА НА БИРАТА

Ивелин Кулев

МЕТЕОРИТЪТ ОТ БЕЛОГРАДЧИК

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

Книжка 4
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

Книжка 2
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

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

Книжка 4
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

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

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

ПОВИШАВАНЕ ИНТЕРЕСА КЪМ ИСТОРИЯТА НА ХИМИЧНИТЕ ЗНАНИЯ И ПРАКТИКИ ПО БЪЛГАРСКИТЕ ЗЕМИ

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

Мария Николова Национална Априловска гимназия – Габрово

ПРИРОДОНАУЧНОТО ОБРАЗОВАНИЕ В БЪЛГАРИЯ – ФОТОАРХИВ

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

Стефка Михайлова Езикова гимназия „Акад. Людмил Стоянов“ – Благоевград

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

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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

Книжка 1
MURPHY’S LAW IN CHEMISTRY

Milan D. Stojković

42-рa МЕЖДУНАРОДНА ОЛИМПИАДА ПО ХИМИЯ

Донка Ташева, Пенка Цанова

СЕМЕЙНИ УЧЕНИЧЕСКИ ВЕЧЕРИНКИ

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