Обучение по природни науки и върхови технологии

https://doi.org/10.53656/nat2022-4.04

2022/4, стр. 359 - 370

„TAP, TAP WATER“ QUANTUM TUNNELING DEMONSTRATION

Katarina Borković
E-mail: kacaborkovic@gmail.com
General Gymnasium of the Catholic School Centre
Srpska 30 Banja Luka 78000
Bosnia and Herzegovina
Andreana Kovačević Ćurić
OrcID: 0000-0002-1773-6765
E-mail: andreanakc88@gmail.com
General Gymnasium of the Catholic School Centre
Srpska 30 Banja Luka 78000
Bosnia and Herzegovina

Резюме: Quantum tunneling is a phenomenon in which an atom or a subatomic particle appears on the other side of a potential barrier that should be impenetrable to the particle, given the difference between the kinetic energy of the particle and the potential energy of the barrier, the former being significantly lesser. However, if the barrier shrinks enough the particle will be able to tunnel right through it. This is among the most well-known quantum physics phenomena. Historically, physicists struggled to grasp the wavelike and particle-like duality of light and subatomic particles. The aforementioned phenomenon occurs due to the wavelike behavior of photons. Quantum phenomena, such as quantum tunneling, might appear quite convoluted, therefore a simple experimental demonstration was performed to highlight the basic mechanisms of the phenomenon in a manner comprehensible to the wide masses. The demonstration, however, is just what we are in fact observing instead of quantum tunneling – “optical tunneling”, perhaps more commonly known as Frustrated Total Internal Reflection (FTIR). This mathematically analogous phenomenon serves as a mere tool for explaining quantum tunneling while aiding our understanding of it and facilitating its visualization. The experimental demonstration shall prove that quantum tunneling is a daily occurring phenomenon and that it is possible once the barrier is thin enough. If these arguments are indeed met with a successful visual demonstration a wavelike character of the photons happens to be confirmed as well.

Ключови думи: quantum tunneling (process); potential barrier; kinetic energy; potential energy; photons; Frustrated Total Internal Reflection (FTIR)

1. Introduction

For a complex concept such as quantum tunneling to seem even comprehensible a brief insight into historical events, emphasizing the nature of quantum logic, as different from the logic of classical physics we know, shall prove to be helpful. Classical physics was entrenched as a seasoned discipline capable of explaining particle motions in unambiguous and deterministic ways, especially in the 17th century. However, it did not encompass all aspects of the physical world that were known at the time. The unresolved matter of the nature of light was one of the lingering questions that undermined the view that all big ideas of physics were now known and all that remained is to sort out the specifics with more precision. It was not until the 19th century that significant progress was made in determining the nature of light. Thomas Young produced highly persuasive evidence in 1801, demonstrating that light has the characteristics of wave motion. Young’s primary findings focused on what we now term interference phenomena (e.g., Newton’s rings). His views seemed to have put an end to the situation. Light has a wave-like appearance. The same claim has been backed up by the electromagnetism theory of James Clerk Maxwell in 1873. However, much more evident and baffling was another problem, originally identified by Lord Rayleigh in 1900 and dubbed “the ultraviolet disaster”. The calamity occurred because classical statistical physics estimates that each degree of freedom in the system will get the same fixed amount of energy, a number that is only dependent on temperature. Max Planck had devised an ingenious solution to the problem proposing that radiation was released or absorbed in discrete packets of energy. He stipulated that the energy level of one of these quanta (or packets) would be proportional to the frequency of the radiation. The proportionality constant, now known as Planck’s constant, was assumed to be a universal constant of nature. Concurrently with these developments in physics, chemists provided helpful data regarding atom composition. J. J. Thomson discovered in 1897 that the negative charge in an atom was carried by small particles, which were later dubbed ‘electrons.’ The balancing positive charge was thought to be simply distributed throughout the atom. This concept was named “the plum pudding model”, with electrons playing the part of plums and positive charge playing the role of pudding. Ernest Rutherford began investigating how microscopic, positively charged projectiles known as α -particles behaved when they collided with a thin gold film in 1911. Many α-particles passed through little affected but some were substantially deflected. The positive charge of the gold atoms, which would repel the positive α-particles, could not be spread out as in a ‘pudding’ but must all be concentrated at the center of the atom. The plum pudding model instantly gave way to the ‘solar system’ model of the atom. Rutherford had discovered the atomic nucleus. Niels Bohr proposed a breakthrough idea in 1913. He applied to atoms the same ideas that Planck applied to radiation. A classical physicist would have assumed that electrons orbiting a nucleus may do so in orbits of any radius. Bohr advocated replacing this continuous option with a discrete constraint that the radii only take one of a set of unique values that could be enumerated (first, second, third etc.). Additionally, he provided a clear prescription on how to compute these potential radii using Planck’s constant, h. Albert Einstein revealed the enigma of the photoelectric effect in 1905, which proved to be the next phase in the unfolding saga of quantum theory. He noticed that below a certain critical frequency, no electrons were emitted, however intense the beam might be; above that frequency, even a weak beam could eject some electrons. This perplexing behavior became instantly perspicuous when the light beam was seen as a stream of persistent quanta. An electron would be expelled because one of these quanta collided with it and gave up all of its energy. According to Planck, the quantity of energy in the quantum was proportional to the frequency. However, these findings indicated that light was particle like, which arose confusion among scientists. Modern quantum theory was entirely enhanced between 1925 and 1926, for which two men were predominantly responsible. Werner Heisenberg had been striving to fathom the subtleties of atomic spectra until 1925, when he achieved a significant breakthrough. The computations appeared to be rather complex, as they involved manipulation of mathematical structures known as matrices. As a result, Heisenberg’s finding became known as matrix mechanics. Following Heisenberg’s discovery, a radically different-looking version of quantum theory emerged, based on the considerably more approachable mathematics of wave equations. This second interpretation of quantum theory was known as wave mechanics, it was found in its fully evolved form by the Austrian scientist Erwin Schrödinger. Prior to this, in his PhD dissertation Prince Louis de Broglie boldly proposed that if undulating light exhibited particle like features, then particles such as electrons should have wavelike properties. De Broglie was able to quantify this hypothesis by generalizing the Planck formula. It had rendered particle like property – energy to be proportionate to wavelike property – frequency. He then proposed that another particle like property – momentum is inversely proportional to another wavelike property – wavelength, with Planck’s universal constant serving as the relevant constant of proportionality once more. These equivalences served as a sort of mini-dictionary for converting particles to waves and vice versa. Early in 1926, Erwin Schrödinger published the famous equation that bears his name. Reversing the kind of reasoning that had led from wave optics to geometrical optics, according to Schrödinger, may lead to the discovery of this wave mechanics. In this manner, he found Schrödinger’s equation. This equation is the fundamental dynamical equation of quantum theory. Heisenberg and Schrödinger had clearly made significant strides. However, the manner they presented their ideas seemed to be so dissimilar that it was unclear if they had made the same discovery, but articulated it differently, or whether they were presenting two competing ideas. Immediate clarification work ensued, with Max Born in Göttingen and Paul Dirac at Cambridge playing key roles. Dirac’s “Principles of Quantum Mechanics”, initially published in 1930, encapsulated the general principles most succinctly. The concept that mater acts as both a wave and a particle is central to quantum mechanics. Now interposing core concept of this experimental demonstration:

Quantum tunneling is a microscopic phenomenon where a particle can penetrate, and in most cases, pass through a potential barrier. The maximum height of the barrier is assumed to be higher than the kinetic energy of the particle, therefore such a motion is not allowed by the laws of classical dynamics. Tunneling occurs in all quantum systems. It is crucial for nucleosynthesis in stars and may have had an essential role in the evolution of the early universe. Since its inception quantum tunneling has remained a hot topic, with myriad applications to this day, especially in modern electronics technology (programmable devices, the tunnel diode, quantum computing, and the scanning tunneling microscope). Among all the triumphs of quantum mechanics, as it developed in the third decade of the twentieth century, none was more astounding than the comprehension of the tunnel effect (Polkinghorne 2002; Razavy 2003; Wichmann 1967).

2. Experimental quantum tunneling demonstration in everyday life

When assessing incredibly small objects, principles of classical mechanics / physics do not operate so well, assuming that we are observing an electron. If that is the case, we can no longer predict where it will be at some future time, but we must provide a probability curve of where it is most likely to be at the time of measuring. As a result, some peculiar things can occur, one of which is quantum tunneling. But even on the quantum scale, if something is fairly thick, there is a near-zero probability that you will ever measure the electron on the other side of such a barrier. However, if that barrier becomes very thin, there is a nonzero probability that you will find the electron on the other side of the barrier without ever breaking the barrier.

2.1. Frustrated Total Internal Reflection as demonstrated analogy of quantum tunneling

For a long time Frustrated Total Internal Reflection (FTIR) at plane interfaces has been regarded as an optical counterpart of quantum mechanical tunneling through a potential barrier (hence the other name – “optical tunneling”), attracting considerable interest as an experimentally accessible system for measuring tunneling times (Chiao, Kwiat & Steinberg 1991; Smith & Blaylock 2017), studying wave packet reshaping (Dyrting, Milburn & Holmes 1993), and providing an optical realization of strange quantum-mechanical effects such as quantum evaporation (Heller 2001). The premise for the quantum-optic analogy is the formal resemblance between the temporal Schrödinger equation for a quantum particle (such as an electron) in potential wells driven by an external electromagnetic field and the scalar and paraxial optical wave equation describing the spatial propagation of a monochromatic light beam through weakly curved (or twisted) guiding dielectric structures. Exact details revealing the mathematical nature and conditions of the analogy between quantum and optical tunneling is discussed by Longhi in “Resonant tunneling in frustrated total internal reflection” and “Dynamical tunneling theory and experiment” (Longhi 2005; Longhi 2011).

“When light is incident on the interface of two media, it is partly transmitted into the second medium and partly reflected back into the first one. If, however, the index of refraction of the first medium (n1) is greater than the index of refraction of the second medium (n2) and the angle of incidence exceeds the critical angle [ ], total internal reflection occurs. The incident light is reflected completely back into the first medium.” (Fig. 1) (Zhu, Yu, Hawley & Roy 1986).

Figure 1. Critical angle behaviour1)

In contrast to what the first figure implies, things are not as straightforward as they seem. In fact, the totality of total internal reflection is a rather debatable affair, as it is ensued by another phenomenon – evanescent waves. When light strikes the interface of two mediums past the critical angle it doesn’t completely reflect, part of it (evanescent waves) penetrates the second medium where it gradually fades out (Fig. 2).

Figure 2. Evanescent wave2)

Even if it seems indiscernible to the naked eye during the total internal reflection, the waves are somewhat existent in the second medium as well, which enables phenomena such as FTIR and Attenuated Total Reflection (ATR) to occur. Both of the aforementioned phenomena occur once the third medium with a refractive index similar to that of the first one (n3 n1) is introduced to the system at close proximity. Such an array of the three mediums makes it so that the second medium now appears as a gap between the first and the third one. Once the second medium is thin enough (thickness about equal to the incident wave’s wavelength) the evanescent wave doesn’t die out in the second medium but is rather ‘frustrated’ so it passes through the second medium into and possibly beyond the third medium as well. Described occurrence is the aforementioned FTIR (Fig. 3). If, however, the second medium happens to possess absorbing qualities which make it a constant ‘drain’ to the incident wave that is being reflected we are discussing ATR.

Figure 3. Frustrated total internal reflection diagram3)

2.2. Quantum tunneling from the standpoint of physics

A potential barrier is a circumstance in which a free particle encounters an area of space where a repulsive force acts upon it, and the potential energy V0 of that interaction is greater than the particle’s kinetic energy E (Fig. 4). If the barrier has a finite thickness d, as shown in the figure, the exact solutions of the Schrödinger equation reveal that the particle is most likely to be reflected from it. However, beyond the barrier, the wave function is not equal to zero, and there is a finite probability that the particle is on the opposite side of the barrier. The exiting wave function has a reduced amplitude but the same wavelength as the incident one,

therefore its energy remains constant as it passes through the barrier. Because each wave function must be continuous and smooth, and therefore must transit from one region to another without fractures nor interruptions, oscillatory wave functions on both sides of the barrier are connected by an exponentially decaying function within the barrier. If it were a classical particle, this would contradict the rule of conservation of energy and could not happen. Comparable phenomena occur with classical electromagnetic waves, and similarly particle’s wavelike nature qualitatively interprets this phenomenon (Feynman, Leighton & Sands 1977).

Figure 4. The potential barrier and wave function of a particle before it encounters a barrier, while within a barrier, and after passing through the barrier4)

2.3. The experiment and materials required

Materials required for observing an enticing phenomenon, such as quantum tunneling could not be any more accessible. The observation apparatus consisted solely of a glass filled with water. It may appear straightforward, but there are certain details to bear in mind. The observed system could easily be affected by environmental factors (e.g., thermal reactions). To avoid any interference with the demonstration’s outcome, we utilized a cold glass (room temperature) and room temperature water (which was 22 degrees at the time in our lab). If by any chance

it was not so, some visibility restrictions on the glass and disturbances would trespass such as condensation if the water were cold or the evaporation if water was hot, also the heated glassware once met with cold water is at risk of shattering. The experiment will be discussed now that the observation circumstances have been established.

Figure 5. Refractive index of some common materials5)

The particles observed in the experiment are photons, and the impenetrable barrier is in fact a reflective surface – the boundary between water and outer air. Because water and air have different indexes of refraction (Fig. 5), the boundary between the two can behave as a completely reflective mirror. When light is shone out of water past a critical angle, it does not leave the water, but rather reflects off its surface and returns to the water, a phenomenon known as total internal reflection (Fig. 1).

When holding the glass sideways (Fig. 6), the fingers are observable on the other side of the glass, but once when held upright (Fig. 7), the size of the glass changes to that of a mirror, and nothing outside of it is visible. When moving anything down the side of the glass, it is visible, but as soon as it sinks below the surface of the water, it is no longer apparent, thus this water glass boundary is acting as a barrier, not allowing any light to pass through, therefore no light is getting from the fingers to the outside of the glass up through the camera, as is depicted below. This is happening because the air has a lower refractive index than that of the glass and water, so the probability of finding a photon omitted is higher.

Figure 6. Glass held horizontally6)

Figure 7. Holding glass vertically7)

However, if the boundary is to be made small enough, that is if that layer of air becomes thin enough, the light is observable, so the photons from my finger can quantumly tunnel through the boundary layer of air and get to the camera. If we press extremely hard and attempt to reduce the air barrier between the finger and the glass as much as possible, the fingertips become visible. (Fig. 8) As per the figure, one may argue that what we observe is not FTIR given the absence of a chromatic effect (such as coloration due to the frustration of the evanescent wave). However according to Snell’s Law and Electrodynamics in general the wave (evanescent or regular) when trespassing into another medium only changes in regard to its speed and wavelength, while the color-dependent component - frequency remains a constant. Although transmitted evanescent waves do die out eventually which is apparent by the fingertips being engulfed in a white-misty color that contrasts the reddish skin tone.

The only way these photons are getting through this barrier is because we`ve reduced the barrier to a small enough thickness that the photons actually tunnel right through it. Another way to do this instead of pressing really hard with the fingers is reducing that boundary of air in between just by getting the finger wet. Now that the fingers are wet instead of air in between photons and reflective surface there’s water. The water has roughly the same index of refraction as the glass and the water inside of the glass, so you can easily see the fingers. Having that water on the finger quickly reduces the layer of air so that the photons from the finger can get to the camera (Fig. 9).

Figure 8. Pressing the glass8)

Figure 9. Touching the glass with wet finger9)

3. Results and discussion

The experiment itself was made up of four assessment points, each providing useful information. The first assessment point (Fig. 6) was mainly referential (glass held sideways). The second assessment point however demonstrated that an invisible barrier in fact does exist (Fig. 7), even if one is to claim otherwise due to glass and water being transparent materials. The third assessment point (Fig. 8) confirms the hypothesis of tunneling occurring once the barrier happens to be tightened enough. Also, this point demonstrates that doing so mechanically will provide wanted results. However, the last assessment point (Fig. 9) emphasizes the role that index refraction values hold in this scenario. The experiment as a whole confirms the wavelike behavior of photons. The main purpose of the demonstration lies in fact in its simplicity. It is easy to replicate and further develop, but still effectively manages to visually demonstrate complex phenomena such as quantum tunneling, even if it is represented by a mathematically analogous phenomenon (FTIR).

4. Conclusion

The main purpose of the experiment was to visually demonstrate quantum tunneling and to confirm the principles by which it operates using its optical counterpart (FTIR). The materials utilized in an experiment themself indicate that a phenomenon can occur even in the simplest systems (water-glass-air), hence proving the daily presence of the tunneling effect in our lives. Since the fingers were

visible once the glass had been mechanically pressed, the hypothesis regarding the barrier reduction has been proved as well. Further analyses of the experiment using different mediums substituting water could prove to be useful and could possibly emphasize the importance of refraction indexes even more. Also, the system once spectroscopically assessed could provide interesting information regarding energy during the tunneling effect occurring, and could perhaps give insight into more crucial processes.

NOTES

1. Figure 1: Critical angle behaviour. Available at: https://www.researchgate.net/ figure/Shows-a-critical-angle-behavior-12_fig4_355432907 [Accessed 10 Aug, 2022].

2. Figure 2: Evanescent wave. Available at: https://commons.wikimedia.org/wiki/ File:Evanescent_wave.png. [Accessed 15 August 2022].

3. Figure 3: Frustrated total internal reflection diagram. Available at: https://study. com/cimages/multimages/16/frustrated_tir_diagram_fixed.png. [Accessed 15 August 2022].

4. Figure 4: The potential barrier and wave function of a particle before it encounters a barrier, while within a barrier, and after passing through the barrier. Available at: http://hyperphysics.phy-astr.gsu.edu/hbase/quantum/barr.html. [Accessed 25 June 2022].

5. Figure 5: Refractive index of some common materials. Available at: https:// www.scienceabc.com/pure-sciences/what-index-of-refraction-defintion-examples-water-air-glass.html. [Accessed 25 June 2022].

6. Figure 6: Glass held horizontally. Borković, K., 2022. Glass held horizontally. [image]. [Accessed 25 June 2022].

7. Figure 7: Holding glass vertically. Borković, K., 2022. Holding glass vertically. [image]. [Accessed 25 June 2022].

8. Figure 8: Pressing the glass. Borković, K., 2022. Pressing the glass. [image]. [Accessed 25 June 2022].

9. Figure 9: Touching the glass with wet finger. Borković, K., 2022. Touching the glass with wet finger. [image]. [Accessed 25 June 2022].

REFERENCES

POLKINGHORNE, J., 2002. Quantum theory. Oxford: Oxford University Press.

RAZAVY, M., 2003. Quantum theory of tunneling. World Scientific Publishing Company.

WICHMANN, E., 1967. Quantum physics. Volume 4. New York: McGrawHill.

CHIAO, R., KWIAT, P. & STEINBERG, A., 1991. Analogies between electron and photon tunneling. Physica B: Condensed Matter. 175(1 – 3), 257 – 262.

SMITH, K. & BLAYLOCK, G., 2017. Simulations in quantum tunneling. American Journal of Physics. 85(10), 763 – 768.

DYRTING, S., MILBURN, G. & HOLMES, C. A., 1993. Nonlinear quantum dynamics at a classical second order resonance. Phys. Rev. E. 48, 969 – 978.

HELLER, E. J., 2001. Quantum physics: Air juggling and other tricks. Nature. 412, 33 – 34.

LONGHI, S., 2005. Resonant tunneling in frustrated total internal reflection. Optics Letters. 30 (20).

LONGHI, S., 2011. Dynamical tunneling theory and experiment. Taylor and Francis Group, LLC. Chapter 13.

ZHU, S., YU, A., HAWLEY, D. & ROY, R., 1986. Frustrated total internal reflection: A demonstration and review. American Journal of Physics. 54(7), 601 – 607.

FEYNMAN, R., LEIGHTON, R. & SANDS, M., 1977. The Feynman lectures on physics, volume IIi: Mainly electromagnetism and matter. 6th Ed. By California Institute Of Technology, Chapter 33.

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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