Academic literature on the topic 'Bohr model'
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Journal articles on the topic "Bohr model"
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Nanni, Luca. "Relativistic Bohr model." Physics Essays 32, no. 1 (2019): 73–76. http://dx.doi.org/10.4006/0836-1398-32.1.73.
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Malte, Hans, and Gunnar Lykkeboe. "The Bohr/Haldane effect: a model-based uncovering of the full extent of its impact on O2 delivery to and CO2 removal from tissues." Journal of Applied Physiology 125, no. 3 (2018): 916–22. http://dx.doi.org/10.1152/japplphysiol.00140.2018.
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For a century, the influence of the Bohr effect on the utilization of blood-borne oxygen has been deemed secondary to its influence on the uptake of carbon dioxide by the blood. Here, we show that the opposite is the case. Using a simple two-ligand, two-state formulation, we modeled the simultaneous oxygen and proton binding to hemoglobin, as well as the resulting acid-base changes of the surrounding solution. Blocking of the Bohr effect in this model system results in a dramatic increase in the oxygen affinity, as expressed by the oxygen partial pressure at half saturation, the P50. It also becomes clear that the P50 and the Bohr factor (a measure of the size of the Bohr effect) are not independent but directly related. Thus, everything else being equal, varying the number of Bohr groups from 0 to 8 per tetramer results in an increase in the Bohr factor from 0 to −0.9 and an increase in P50 from 6 to 46 mmHg at a constant Pco2 of 40 mmHg. Therefore, changes in hemoglobin structure that lead to changes in the Bohr factor will inevitably also change hemoglobin oxygen affinity. NEW & NOTEWORTHY Using a mathematical model, we show that the Bohr effect has a more profound effect on gas exchange than is evident when comparing oxygen equilibrium curves measured in the laboratory at different constant values of Pco2 or pH. Protons preloaded on the Bohr groups, as well as the protons taken up during oxygen unloading, dramatically decrease oxygen affinity of the physiological oxygen equilibrium curve. Therefore, the Bohr effect is instrumental in setting the oxygen affinity.
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Khare, Avinash. "One hundred years of Bohr model." Resonance 18, no. 10 (2013): 885–96. http://dx.doi.org/10.1007/s12045-013-0115-2.
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KRUPIŃSKI, KRZYSZTOF, and ANAND PILLAY. "Generalised Bohr compactification and model-theoretic connected components." Mathematical Proceedings of the Cambridge Philosophical Society 163, no. 2 (2016): 219–49. http://dx.doi.org/10.1017/s0305004116000967.
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AbstractFor a group G first order definable in a structure M, we continue the study of the “definable topological dynamics” of G (from [9] for example). The special case when all subsets of G are definable in the given structure M is simply the usual topological dynamics of the discrete group G; in particular, in this case, the words “externally definable” and “definable” can be removed in the results described below.Here we consider the mutual interactions of three notions or objects: a certain model-theoretic invariant G*/(G*)000M of G, which appears to be “new” in the classical discrete case and of which we give a direct description in the paper; the [externally definable] generalised Bohr compactification of G; [externally definable] strong amenability. Among other things, we essentially prove: (i) the “new” invariant G*/(G*)000M lies in between the externally definable generalised Bohr compactification and the definable Bohr compactification, and these all coincide when G is definably strongly amenable and all types in SG(M) are definable; (ii) the kernel of the surjective homomorphism from G*/(G*)000M to the definable Bohr compactification has naturally the structure of the quotient of a compact (Hausdorff) group by a dense normal subgroup; (iii) when Th(M) is NIP, then G is [externally] definably amenable iff it is externally definably strongly amenable.In the situation when all types in SG(M) are definable, one can just work with the definable (instead of externally definable) objects in the above results.
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Borrelli, Arianna. "Niels Bohr and the Quantum Atom: The Bohr Model of Atomic Structure 1913–1925." International Studies in the Philosophy of Science 27, no. 2 (2013): 222–24. http://dx.doi.org/10.1080/02698595.2013.813250.
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Rapoport, D. M., R. G. Norman, and R. M. Goldring. "CO2 homeostasis during periodic breathing: predictions from a computer model." Journal of Applied Physiology 75, no. 5 (1993): 2302–9. http://dx.doi.org/10.1152/jappl.1993.75.5.2302.
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The Bohr/Riley model of CO2 homeostasis describes the relationship between CO2 production, ventilation, and arterial PCO2 and assumes that ventilation and CO2 delivery to the lung are both anatomically and temporally well matched. In contrast to normal breathing, periodic patterns of ventilation show temporal mismatch of ventilation to CO2 delivery. We developed a computer model of lung CO2 clearance that uses CO2 transfer equations to generate iterative solutions for PCO2 in multiple body compartments as a function of time. During continuous ventilatory patterns our model predicts steady-state arterial PCO2 identical to that of the Bohr model. During periodic ventilation, we predict mean PCO2 will be elevated unless mean ventilation is increased above that required by the Bohr model. Waxing and waning tidal volumes, low functional residual capacity, and low capillary blood volume potentiate the hypercapnia. However, if cardiac output oscillates in phase with breathing, hypercapnia is minimized. This analysis suggests a new mechanism for the development of sustained hypercapnia, separate from absolute hypoventilation or the presence of lung disease.
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Gong-ou, Xu, Li Fu-li, and Fu De-ji. "Microscopic aspects of the Bohr-Mottelson model." Physical Review C 43, no. 3 (1991): 1216–24. http://dx.doi.org/10.1103/physrevc.43.1216.
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Chen, Goong, Zhonghai Ding, Sze-Bi Hsu, Moochan Kim, and Jianxin Zhou. "Mathematical analysis of a Bohr atom model." Journal of Mathematical Physics 47, no. 2 (2006): 022107. http://dx.doi.org/10.1063/1.2168396.
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Bloom, Danning, and Dan W. Bloom. "Vibrating Wire Loop and the Bohr Model." Physics Teacher 41, no. 5 (2003): 292–94. http://dx.doi.org/10.1119/1.1571265.
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Bonatsos, Dennis, D. Lenis, D. Petrellis, and P. A. Terziev. "W(5): Wobbling Mode in the Framework of the X(5) Model." HNPS Proceedings 13 (February 20, 2020): 214. http://dx.doi.org/10.12681/hnps.2971.
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Using in the Bohr Hamiltonian the approximations leading to the Bohr and Mot- telson description of wobbling motion in even nuclei, a W(5) model for wobbling bands, coexisting with a X(5) ground state band, is obtained. Separation of vari ables is achieved by assuming that the relevant potential has a sharp minimum at 70, which is the only parameter entering in the spectra and B(E2) transition rates (up to overall scale factors). B(E2) transition rates exhibit the features expected in the wobbling case.
Dissertations / Theses on the topic "Bohr model"
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Urtekin, Kerim. "Bohr model and dimensional scaling analysis of atoms and molecules." Texas A&M University, 2006. http://hdl.handle.net/1969.1/4660.
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It is generally believed that the old quantum theory, as presented by Niels Bohr
in 1913, fails when applied to many-electron systems, such as molecules, and nonhydrogenic
atoms. It is the central theme of this dissertation to display with examples
and applications the implementation of a simple and successful extension of BohrâÂÂs
planetary model of the hydrogenic atom, which has recently been developed by an
atomic and molecular theory group from Texas A&M University. This âÂÂextendedâÂÂ
Bohr model, which can be derived from quantum mechanics using the well-known
dimentional scaling technique is used to yield potential energy curves of H2 and several
more complicated molecules, such as LiH, Li2, BeH, He2 and H3, with accuracies
strikingly comparable to those obtained from the more lengthy and rigorous âÂÂab initioâÂÂ
computations, and the added advantage that it provides a rather insightful and
pictorial description of how electrons behave to form chemical bonds, a theme not
central to âÂÂab initioâ quantum chemistry. Further investigation directed to CH, and
the four-atom system H4 (with both linear and square configurations ), via the interpolated
Bohr model, and the constrained Bohr model (with an effective potential),
respectively, is reported. The extended model is also used to calculate correlation
energies.
The model is readily applicable to the study of molecular species in the presence
of strong magnetic fields, as is the case in the vicinities of white dwarfs and neutron
stars. We find that magnetic field increases the binding energy and decreases the bond length.
Finally, an elaborative review of doubly coupled quantum dots for a derivation of
the electron exchange energy, a straightforward application of Heitler-London method
of quantum molecular chemistry, concludes the dissertation.
The highlights of the research are (1) a bridging together of the pre- and post
quantum mechanical descriptions of the chemical bond (Bohr-Sommerfeld vs Heisenberg-
Schrèodinger), and (2) the reporting of the appearance of new bound states of H2 in
the presence of very strong magnetic fields. The new states emerge above the critical
value of 5 ÃÂ 107 G, and hence cannot be obtained perturbatively.
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Silva, Giovanna Stefanello. "A ABORDAGEM DO MODELO ATÔMICO DE BOHR ATRAVÉS DE ATIVIDADES EXPERIMENTAIS E DE MODELAGEM." Universidade Federal de Santa Maria, 2013. http://repositorio.ufsm.br/handle/1/6671.
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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior<br>Knowing and understanding the Chemistry concepts is directly related to the capability of moving between the three levels of representation which concern Chemistry. Each one of these levels involve the developing of different abilities, as the capability of abstraction. There are several Chemistry concepts which depend on this articulation between the macroscopic, microscopic and symbolic levels, for example, the study of the matter structure. Though, it is noticed that a large part of the students show difficulties in comprehending the transition between the levels of representation and therefore identifying the relation between the chemical concepts and their everyday lives, this is why it is important to know the concepts of the students. With the purpose of helping the students in the construction, visualization and application of the knowledge which involve the study of the atom, especially the Bohr atomic model, with facts of their daily lives, in this study we elaborated and developed different experimental and modeling activities. Moreover, we evaluated the didactic objective of the visual resources present in the five textbooks approved by the PNLD-2012, in relation to the atomic structure. This analysis was done duo to the importance of this material in class and its use as research source in some activities developed in this research, as the images present in the textbooks may help the students in the relation between the theory and the practice during the process of imagining some chemical phenomenon. In a general way, we observed that there is diversity in the way the visual resources are used in the textbooks concerning the Bohr atomic model. This study was taken with thirty seven subjects in a class of freshman students in the city of Júlio de Castilhos, RS. The data taken in seven interventions was analyzed and categorized according to the methodology of the discursive text analyses. After the analyses of the data, the results showed that the different developed interventions, either through experimental or modeling activities, collaborated to the students to correlate the chemical concepts acquired in the classroom with several phenomena of their routine. Furthermore, it helped them to formulate their own relation between the macroscopic and the microscopic by their own observation, discussion, and idea interpretation using the Chemistry codes and symbols. Thus it can be said that, after the interventions, students were able to move between the three levels of representation of matter. These implications show that the teaching of Chemistry needs to provide students with differentiated classes in the attempt that they are able to identify and relate Chemistry as an integral part of their lives.<br>Conhecer e compreender os conceitos químicos está diretamente relacionado com a capacidade de transitar entre os três níveis de representação que permeiam a Química. Cada um desses níveis envolve o desenvolvimento de diferentes habilidades, dentre elas, a capacidade de abstração. Inúmeros são os conceitos químicos que dependem dessa articulação entre os níveis macroscópico, microscópico e simbólico, como por exemplo, o estudo da estrutura da matéria. Porém, o que se percebe é que grande parte dos estudantes apresenta dificuldades em compreender a transição entre os níveis de representação e consequentemente identificar as relações entre os conceitos químicos e seu cotidiano, por isso a importância de se conhecer as concepções dos alunos. Com o propósito de auxiliar os estudantes na construção, visualização e aplicação dos conhecimentos que envolvem o estudo do átomo, em específico o modelo atômico de Bohr, com fatos de seu dia a dia, neste trabalho elaboramos e desenvolvemos diferentes atividades experimentais e de modelagem. Além disso, avaliamos o objetivo didático dos recursos visuais presentes nos cinco livros didáticos aprovados pelo PNLD-2012, em relação à estrutura atômica. Esta análise foi realizada devido à importância desse material em sala de aula e à sua utilização como fonte de pesquisa em algumas atividades desenvolvidas nesta pesquisa, já que as imagens presentes nos livros didáticos podem auxiliar os estudantes nas relações entre a teoria e a prática durante o processo de imaginar alguns fenômenos químicos. De maneira geral, constatamos que há uma diversidade na forma como os recursos visuais são utilizados pelos livros didáticos na abordagem do modelo atômico de Bohr. O trabalho realizado nesta pesquisa foi desenvolvido com trinta e sete sujeitos, de uma turma da primeira série do ensino médio de uma escola pública da cidade de Júlio de Castilhos-RS. Os dados obtidos em sete intervenções foram analisados e categorizados conforme a metodologia da análise textual discursiva. Após a análise dos dados, os resultados demonstram que as diferentes intervenções desenvolvidas, seja através de atividades experimentais ou de modelagem, colaboraram para que os estudantes relacionassem os conceitos químicos aprendidos em sala de aula com diversos fenômenos de seu cotidiano. Além disso, auxiliaram para que eles a partir de suas observações, discussões, interpretações e ideias formulassem suas próprias relações entre o macroscópico e o microscópico, utilizando símbolos e códigos da Química, desta forma, pode-se afirmar que, após as intervenções, os estudantes foram capazes de transitar entre os três níveis de representação da matéria. Essas implicações evidenciam que o ensino de Química precisa proporcionar aos estudantes aulas diferenciadas na tentativa de que estes consigam identificar e relacionar a Química como parte integrante de sua vida.
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Penna, Marcos. "A investigacao da estrutura da matéria no início do século XX: Niels Bohr e a busca de explicações para a estabilidade do átomo." Pontifícia Universidade Católica de São Paulo, 2009. https://tede2.pucsp.br/handle/handle/13420.
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Previous issue date: 2009-05-14<br>Secretaria da Educação do Estado de São Paulo<br>The aim of this abstract is to study the formulation of Niels Bohr´s atomic model in the beginning of the twentieth century, regarding the atomic model of Rutherford. The issues about instability resulting from this model and the observation that the classical mechanic could not express the atomic reality were both intensively approached themes those days. Besides that, spectroscopy data showed that the raising of spectral lines, characteristic of chemical elements, should be explained by an atomic model.
The classical mechanic is replaced in the analysis of the atomic phenomena under Bohr´s atomic model. After Max Planck´s ideas, the energy from the atomic processes is not absorbed nor is it continually freed. Actually it is found in the form of energy packages called quanta.
To develop his atomic model, Bohr uses studies from Rutherford experiments as well as works about the spectral lines observed from spectroscopic analyses on chemical elements, in which each chemical element can be identified from the light spectrum emitted when this element after receiving energy changes the orbit and remains unstable, freeing an amount of energy in the form of light at the moment that it returns to its stable state<br>Esta dissertação tem como objetivo o estudo da formulação do modelo atômico de Niels Bohr no inicio do século XX, a partir do modelo atômico de Rutherford.
A questão da instabilidade decorrente desse modelo, bem como a observação de que a mecânica clássica não poderia expressar a realidade atômica foram temas intensamente debatidos naquela época. Além disso, os dados de espectroscopia demonstravam que o aparecimento das riscas espectrais características dos elementos químicos deveria ser explicado por um modelo atômico.
No desenvolvimento do modelo atômico de Bohr, a mecânica clássica e substituída na análise dos fenômenos atômicos. A partir das idéias de Max Planck, segundo as quais a energia dos processos atômicos não é absorvido nem liberada de forma contínua, mais sim na forma de pacotes de energia chamados de quanta.
Para desenvolvimento de seu modelo atômico Bohr se utiliza estudos do experimento de Rutherford e de trabalhos sobre as riscas espectrais observadas a partir de analises espectroscópicas dos elementos químicos, segundo a qual cada elemento químico pode ser identificado a partir do espectro de luz emitido quando o mesmo após receber energia, muda de órbita e fica instável e quando volta ao seu estado de estabilidade libera uma quantidade de energia na forma de luz
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Miranker, Emily. "An Infinity of Questions: Dramatizing Science on Stage." Oberlin College Honors Theses / OhioLINK, 2008. http://rave.ohiolink.edu/etdc/view?acc_num=oberlin1212179899.
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Movahhedian, Hossein. "Locality, Lorentz invariance and the Bohm model." Thesis, Durham University, 1998. http://etheses.dur.ac.uk/4829/.
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Non-local forces exist in nature for two reasons. First that the recent experiments on locality are supposed to be accurate enough. Second that there is no local theory that can reproduce all the predictions of orthodox quantum theory which, almost for about a century, have been proved to be correct experimentally again and again. This thesis concerns both of these. A brief discussion of the measurement in quantum theory is followed by two comments which show that the quantum description is frame dependent and that the collapse of the wave-function of a system may occur without the relevant measurement being performed. After this the Bohm model and a modified version of the Bohm model are described. Next we introduce a new method for obtaining the Bell-type inequalities which can be used for testing locality. We derive more inequalities by this method than obtained by other existing procedures. Using Projection Valued(PV) and Positive Operator Valued Measures(POVM) measurements we have designed experiments which violates one of the Bell inequalities by a larger factor than existing violations which in turn could increase the accuracy of experiments to test for non-locality. This is our first result. After discussing the non-locality and non-Lorentz invariant features of the Bohm model, its retarded version, namely Squires' model - which is local and Lorentz invariant - is introduced. A problem with this model, that is the ambiguity in the cases where the wave-function depends on time, is removed by using the multiple-time wave-function. Finally, we apply the model to one of the experiments of locality and prove that it is in good agreement with the orthodox quantum theory.
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Lusk, Gregory S. "Models and scientific explanation." Ohio : Ohio University, 2009. http://www.ohiolink.edu/etd/view.cgi?ohiou1250816101.
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Matušková, Petra. "Finanční analýza a. s. Crystelex, Nový Bor." Master's thesis, Vysoká škola ekonomická v Praze, 2008. http://www.nusl.cz/ntk/nusl-9165.
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The Financial analysis Crystalex a.s. examines a general financial situation of the company. I use classical methods for financial analysis. The significant part of my project is the application of creditworthy and bankruptcy models. The aim of my thesis is to find out if these models were able to predict the current situation for management in the past.
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Van, der Merwe Daniel Andre. "Developing a model for feedlot production of Boer goat slaughter kids." Thesis, Stellenbosch : Stellenbosch University, 2015. http://hdl.handle.net/10019.1/97903.
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Thesis (MSc)--Stellenbosch University, 2015.<br>ENGLISH ABSTRACT: In this study, the effects of energy content of the feedlot diet as well as the length of the production period were investigated for Boer goat slaughter kids. The kids were housed in individual pens on the Elsenburg experimental farm, Western Cape, South Africa. Boer goat castrate kids were weaned at approximately 18 weeks of age (weighing 22.2 ± 3.5 kg) and were randomly allocated to one of three trial diets that varied in energy content; namely a low, medium and high energy diet (11.3, 12.0 and 12.7 MJ ME/ kg feed respectively) which were supplied ad libitum. The goats were further randomly allocated to one of five slaughter groups that were slaughtered at five week intervals at a commercial abattoir. The first group of goats was slaughtered at the start of the trial in order to serve as a baseline reference. During the study the effects of dietary energy content, and time spent in the feedlot were investigated for the feedlot production and slaughter characteristics of Boer goat kids. Additionally the effect of the energy content of the feedlot diets on the sensory and chemical properties of goat meat were evaluated.
During the production period individual feed intake and live weight gain were monitored on a weekly basis. It was observed that live weight of the goats increased throughout the production period. Quadratic functions were used to describe the change in average daily gain and dry matter intake of the goats during the feeding period. Goats that were fed the low and medium energy diets exhibited higher daily gains (P= 0.02) and dry matter intakes (P< 0.01) than goats on the high energy diets. Dietary energy content and age of the animal in the feedlot did not influence the feed conversion ratio to produce a unit of live weight. A linear function was used to model the growth of the goats during this production period. The goats were not able to reach the point of inflection on the growth curve. Therefore the sigmoidal growth curve could not be plotted which could have been modelled by a function similar to the Gompertz model.
Dressing percentages of the carcasses varied throughout the production period for all the diets, with goats on the low energy diet having the lowest dressing percentage (45.8%; P= 0.04). The energy content of the trial diets had no effect on the yield of the offal components and retail cuts of the carcass. Generally it was observed that the yields of the hindquarter and neck cuts decreased whilst that of the forequarter increased with the age of the goats at slaughter. The degree of carcass fatness increased with time spent in the feedlot, with the majority of fat being deposited in the abdominal cavity, rather than in the subcutaneous fat depot.
Dietary energy content was expected to influence the levels of intramuscular fat, which in turn would affect the eating quality of the meat. However, the levels of energy in the diets fed to goats did not influence the tenderness, juiciness or the aroma and flavour profiles of the goat meat as observed during descriptive sensory analysis of the meat by a trained panel. Chemical analysis of the cooked meat samples also showed that the levels of intramuscular fat did not vary between the samples, resulting in the lack of differences detected between treatments in the sensory evaluation.<br>AFRIKAANSE OPSOMMING: In hierdie studie is die effek van die energie-inhoud van die voerkraal dieet, tesame met die lengte van die produksie tydperk, vir Boerbok lammers ondersoek. Die lammers is in individuele kampies gehuisves op die Elsenburg proefplaas, Wes- Kaap, Suid-Afrika. Die gekastreerde Boerbok lammers is gespeen op ’n ouderdom van ongeveer 18 weke (gewig van 22.2 ± 3.5 kg) en is ewekansig toegewys aan een van die drie proefdiëte waarvan die energie-inhoud gewissel het; naamlik 'n lae, medium en hoë-energie dieet (11.3, 12.0 en 12.7 MJ ME / kg voer onderskeidelik) wat ad libitum verskaf is. Die bokke is verder lukraak toegewys aan een van vyf slag groepe, wat met vyf weke tussenposes by ’n kommersiële abattoir geslag is. Die eerste groep bokke is aan die begin van die proef geslag om sodoende as basislyn verwysing te dien. Tydens die studie is die effek van die verskil in energie-inhoud van die dieet en die tyd wat in die voerkraal gespandeer is, op die voerkraal produksie en slag eienskappe van die Boerbok lammers ondersoek. Daarbenewens is die effek van die verskil in energie-inhoud van die voerkraal dieet op die sensoriese en chemiese eienskappe van bokvleis geëvalueer.
Tydens die produksie periode is individuele voerinname en liggaamsgewig toename op ’n weeklikse basis gemonitor. Dit is waargeneem dat die liggaamsgewig van die bokke tydens die hele produksie tydperk toegeneem het. Kwadratiese funksies is gebruik om die verandering in die gemiddelde daaglikse toename tydens die voerperiode, sowel as die droëmateriaal inname van die bokke te beskryf. Bokke wat die lae en medium-energie diëte gevoer is, het hoër daaglikse toenames (P = 0.02) en droë materiaal inname (P< 0.01) as bokke op die hoë-energie dieet getoon. Die voeromset verhouding benodig om ’n eenheid lewendige gewig te produseer is nie beïnvloed deur die energie-inhoud van die dieet, of die ouderdom van die bokke in die voerkraal nie. ’n Lineêre funksie is toegepas om die groei van die bokke gedurende die produksie tydperk te modelleer. Die groei van die bokke kon nie die infleksiepunt van die groeikurwe bereik nie. Dus kon die sigmoïdale groeikurwe nie getrek word nie, wat deur ’n funksie soortgelyk aan die Gompertz model gemodelleer kon word.
Uitslag persentasies van die karkasse het l regdeur die produksie tydperk varieër vir al die diëte; bokke op die lae-energie dieet het die laagste uitslagpersentasie gehad (45.8%; P = 0.04). Die energie-inhoud van die proefdiëte het geen effek op die opbrengs van die afval komponente en handelsnitte van die karkasse gehad nie. Oorhoofs is dit waargeneem dat die opbrengs van die agterkwart en neksnitte afgeneem het, terwyl dié van die voorkwart toegeneem het met slag ouderdom. Die vetheidsgraad van die karkas het toegeneem met tyd spandeer in die voerkraal, met die meerderheid van die vet gedeponeer in die buikholte, eerder as in die onderhuidse vetlaag.
Daar is verwag dat die energie-inhoud van die dieet die vlakke van binnespierse vet sal beïnvloed, wat op sy beurt ‘n effek op die eetkwaliteit van die vleis sal hê.. Teenstrydig met verwagtinge het die vlakke van energie in die dieet van die bokke geen invloed gehad op die sagtheid, sappigheid of die aroma en geur profiele van bokvleis nie, soos waargeneem deur middel van beskrywende sintuiglike analise van die vleis deur 'n opgeleide paneele. Chemiese ontleding van die gaar vleismonsters het ook geen verskillein die vlakke van binnespierse vet tussen die verskillende monsters getoon nie, wat gelei het tot daar geen verskille tussen die behandelings in die sensoriese evaluasie waargeneem is nie.
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Kim, Ji S. "Electron transport through the double quantum dots in Aharonov-Bohm rings." Virtual Press, 2005. http://liblink.bsu.edu/uhtbin/catkey/1319544.
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We numerically investigate a total transmission probability through QDs embedded in an AB ring. The QDs are formed by delta function-like double potential barriers and a magnetic flux is penetrated in the center of the ring. In particular, we study the coupled double-QDs in series and non-coupled double-QDs in parallel in an AB ring. In each model, we show the total transmission probability as a function of QD size and electron incident energy, and present the transmission amplitude on the complex-energy plane. Of interest is the change and progression of Fano resonances and corresponding zero-pole pairs on the complex-energy plane with magnetic flux in the center of the ring.To accomplish this, we analytically solve the scattering matrix at each junction and the transfer matrix through the arms of the ring using Schrodinger equation for the delta function barriers. Then, the total transmission probability is obtained as a function of electron energy and magnetic flux by cascading these matrices. Finally, the solutions of the analytical equations and the graphical output of the transmission characteristics in the system will be obtained numerically by using Mathematica programs run on desktop computers.<br>Department of Physics and Astronomy
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Mackman, Stephen William. "Gauge fields and quantum theory." Thesis, Durham University, 1996. http://etheses.dur.ac.uk/5183/.
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This thesis investigates the problems within quantum mechanics for the Bohm model caused by Lorentz invariance and the existence of photons. A model describing the electromagnetic interactions of fermions is produced which does not use photons and avoids these problems. It is then shown how these techniques can be extended to linearised gravitational interactions. Finally semi-classical gravity and the possibility of gravitationally induced collapse are considered. In the first part of the thesis two modifications to the Bohm model are proposed. One takes account of Lorentz invariance, and the other is capable of describing photons. The main part of the thesis is devoted to describing interactions in a way which does not need extra gauge particles, and so is in the same spirit as the Bohm model. Electromagnetic interactions are formed using a 4-potential operator which is calculated directly, without imposing commutation relations on the 4-potential. This leads to an expression for the 4-potential in terms of the Dirac field, and results in there being no photon states. There are various ways of constructing the theory and the scattering matrix of standard QED is compared to the scattering matrix of the version which appears to be most similar. Considering only the matrix elements between fermion states, they are found to be in agreement at the order e(^2), but disagree at the order e(^4). It follows that this model, which otherwise appears to be a self consistent theory of QED, cannot agree with experiment. The same techniques can be used to quantise General Relativity when it is linearised about the Minkowski metric. The metric operator is calculated in terms of the Dirac field. The interaction is similar to that of electrodynamics, being of order 4 in the Dirac field. Finally issues relating to gravitational collapse are discussed.
Books on the topic "Bohr model"
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-A, Souentie Stamatios N., and SpringerLink (Online service), eds. Gravity, Special Relativity, and the Strong Force: A Bohr-Einstein-de Broglie Model for the Formation of Hadrons. Springer US, 2012.
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1957-, Lakhtakia A., ed. Models and modelers of hydrogen: Thales, Thomson, Rutherford, Bohr, Sommerfeld, Goudsmit, Heisenberg, Schrödinger, Dirac, Sallhofer. World Scientific, 1996.
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Kuipers, Matthijs. A Metropolitan History of the Dutch Empire. Amsterdam University Press, 2022. http://dx.doi.org/10.5117/9789463729918.
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This book analyses popular imperial culture in the Netherlands around the turn of the twentieth century. Despite the prominent role that the Dutch empire played in many (sometimes unexpected) aspects of civil society, and its significance in mobilising citizens to participate in causes both directly and indirectly related to the overseas colonies, most people seem to have remained indifferent towards imperial affairs. How, then, barring a few jingoist outbursts during the Aceh and Boer Wars, could the empire be simultaneously present and absent in metropolitan life? Drawing upon the works of scholars from fields as diverse as postcolonial studies and Habsburg imperialism, A Metropolitan History of the Dutch Empire argues that indifference was not an anomaly in the face of an all-permeating imperial culture, but rather the logical consequence of an imperial ideology that treated ‘the metropole’ and ‘the colony’ as entirely separate entities. The various groups and individuals who advocated for imperial or anti-imperial causes – such as missionaries, former colonials, Indonesian students, and boy scouts – had little unmediated contact with one another, and maintained their own distinctive modes of expression. They were all, however, part of what this book terms a ‘fragmented empire’, connected by a Dutch imperial ideology that was common to all of them, and whose central tenet – namely, that the colonies had no bearing on the mother country – they never questioned. What we should not do, the author concludes, is assume that the metropolitan invisibility of colonial culture rendered it powerless.
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Kragh, Helge. Niels Bohr and the Quantum Atom: The Bohr Model of Atomic Structure 1913-1925. Oxford University Press, 2012.
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Kragh, Helge. Niels Bohr and the Quantum Atom: The Bohr Model of Atomic Structure, 1913-1925. Oxford University Press, 2012.
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E, Baker Thomas. Revisiting the Bohr Model: Over 50 New Conceptual Theories. Dorrance Publishing Company, Incorporated, 2022.
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Vayenas, Constantinos G. G., and Stamatios N. A. Souentie. Gravity, Special Relativity, and the Strong Force: A Bohr-Einstein-de Broglie Model for the Formation of Hadrons. Springer, 2016.
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Levin, Frank S. The Nuclear Atom. Oxford University Press, 2017. http://dx.doi.org/10.1093/oso/9780198808275.003.0006.
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Chapter 5 describes how the concept of quantization (discretization) was first applied to atoms. This was done in 1913 by Niels Bohr, using Ernest Rutherford’s paradigm-changing, solar-system model of atomic structure, wherein the positively charged nucleus occupies a tiny central space, much smaller than the known sizes of atoms. Bohr, postulating a quantized version of this model for hydrogen, was able to explain previously inexplicable experimental features of that atom. He did so via an ad hoc quantization procedure that discretized the single electron’s energy, its angular momentum, and the radii of the orbits it could be in around the nucleus, formulas forwhich are presented, along with a diagram displaying the quantized energies. Despite this success, Bohr’s model failed not only for helium, with its two electrons, but for all other neutral atoms. It left some physicists hopeful, ready for whatever the next step might be.
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Stuewer, Roger H. The New World. Oxford University Press, 2018. http://dx.doi.org/10.1093/oso/9780198827870.003.0015.
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On December 19, 1938, Otto Hahn wrote to Lise Meitner in Stockholm, asking her if she could propose some “fantastic explanation” for his and Fritz Strassmann’s finding of barium when bombarding uranium with neutrons. She and Otto Robert Frisch found such an explanation for what he called “nuclear fission” over the Christmas holidays, based on Gamow’s liquid-drop model of the nucleus. Bohr was astonished by this, but in 1936 he had speculated that the uranium nucleus would just explode. He, his son Erik, and his associate Léon Rosenfeld then took a ship to New York, arriving on January 16, 1939. Rosenfeld reported the discovery of fission that evening to the Princeton physics journal club. On January 26, physicists everywhere learned about this stunning discovery when Bohr and Fermi reported it at a conference in Washington, D.C. Physicists entered the New World of Nuclear Physics, taking Humanity with them.
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Deruelle, Nathalie, and Jean-Philippe Uzan. Constant fields. Oxford University Press, 2018. http://dx.doi.org/10.1093/oso/9780198786399.003.0031.
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This chapter reviews the basic ideas of electrostatics (Coulomb’s law) and magnetostatics (the Biot–Savart law). It studies the motion of a charge in a Coulomb field in detail. The chapter shows how the motion of a charge q in the Coulomb field of a charge Q held fixed at the origin of an inertial frame is governed by the Lorentz equation. Moreover, it can be solved like the Kepler problem discussed in the previous Book. Next, the chapter discusses the Rutherford scattering formula which established the ‘planetary’ model of the atom, the Bohr–Sommerfeld quantization which displayed the limits of the theory, and finally the spin coupling explaining the atomic fine structure.
Book chapters on the topic "Bohr model"
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Rohlf, James W. "Bohr Model." In Guide to Modern Physics. CRC Press, 2023. http://dx.doi.org/10.1201/9781003395515-5.
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Podgoršak, Ervin B. "Rutherford–Bohr Atomic Model." In Compendium to Radiation Physics for Medical Physicists. Springer Berlin Heidelberg, 2014. http://dx.doi.org/10.1007/978-3-642-20186-8_3.
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Vayenas, Constantinos G., Dionysios G. Tsousis, and Eftychia H. Martino. "The Bohr Model in Chemistry." In Catalysis in Chemistry and Physics. Springer Nature Switzerland, 2024. http://dx.doi.org/10.1007/978-3-031-68122-6_4.
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Podgoršak, Ervin B. "Rutherford–Bohr Model of the Atom." In Graduate Texts in Physics. Springer International Publishing, 2016. http://dx.doi.org/10.1007/978-3-319-25382-4_3.
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Podgoršak, Ervin B. "Rutherford-Bohr Model of the Atom." In Radiation Physics for Medical Physicists. Springer Berlin Heidelberg, 2009. http://dx.doi.org/10.1007/978-3-642-00875-7_3.
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Pannuti, Thomas G. "Angles, Gravity, Light, the Bohr Model of the Atom and Relativity." In Undergraduate Lecture Notes in Physics. Springer International Publishing, 2020. http://dx.doi.org/10.1007/978-3-319-16982-8_2.
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Dürr, Detlef, Sheldon Goldstein, and Nino Zanghì. "Hypersurface Bohm-Dirac Models." In Quantum Physics Without Quantum Philosophy. Springer Berlin Heidelberg, 2012. http://dx.doi.org/10.1007/978-3-642-30690-7_9.
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Bohé, Jacob, Charlotte Feidicker, Angela Gutierrez, Frederic Kunkel, Maria Laura Niewöhner, and Malte Wittmaack. "Making Use of Models." In Comparing and Change. Bielefeld University Press / transcript Verlag, 2024. http://dx.doi.org/10.14361/9783839472668-004.
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Jacob Bohé, Charlotte Feidicker, Angela Gutierrez, Frederic Kunkel, Laura Maria Niewöhner, Malte Wittmaack shed light on the question of how models and modeling could be applied to historical research. Iná three sections, different research fields in History will be explored concerning this question, i.e., economic history, situations of cultural contact, denazification, and the use of models in Digital Humanities. In every section, two authors discuss problems and chances in using models and modeling in their research projects within the SFB 1288 "Practices of comparing".
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Bacciagaluppi, Guido. "Bohm-Bell Dynamics in the Modal Interpretation." In The Western Ontario Series in Philosophy of Science. Springer Netherlands, 1998. http://dx.doi.org/10.1007/978-94-011-5084-2_7.
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Innocenzi, Plinio. "Discovering the Electron. From Dalton to Bohr, Evolving Theories and Models." In What is an Electron? Springer Nature Switzerland, 2025. https://doi.org/10.1007/978-3-031-81984-1_2.
Full textConference papers on the topic "Bohr model"
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Gulshani, P., Ricardo Alarcon, Phil Cole, Andres J. Kreiner, and Hugo F. Arellano. "Microscopic Uni-axial Bohr-Mottelson Rotational Model." In VIII LATIN AMERICAN SYMPOSIUM ON NUCLEAR PHYSICS AND APPLICATIONS. AIP, 2010. http://dx.doi.org/10.1063/1.3480239.
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Hunter, Geoffrey, Marian Kowalski, and Camil Alexandrescu. "The Bohr model of the photon (Invited Paper)." In Optics & Photonics 2005, edited by Chandrasekhar Roychoudhuri and Katherine Creath. SPIE, 2005. http://dx.doi.org/10.1117/12.613287.
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Hunter, Geoffrey. "Einstein’s Photon Concept Quantified by the Bohr Model of the Photon." In QUANTUM THEORY: Reconsideration of Foundations - 3. AIP, 2006. http://dx.doi.org/10.1063/1.2158738.
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Oglah, Mubarak Hamad, Abdulqader Ali Hasan, and Watban Ibrahim Mahmood. "Quantum confinement Bohr radius effects of quantum dots using Brus mathematical model." In INTERNATIONAL CONFERENCE ON EMERGING TECHNOLOGIES IN ENGINEERING AND SCIENCE: ICETES2023. AIP Publishing, 2025. https://doi.org/10.1063/5.0241782.
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Adnan, Mohammed L., and Khalid S. Jassim. "The Bohr-Mottelson model was used to calculate the longitudinal form factor of 31P, 27Al, and 23Na nuclei." In 2ND INTERNATIONAL CONFERENCE OF MATHEMATICS, APPLIED SCIENCES, INFORMATION AND COMMUNICATION TECHNOLOGY. AIP Publishing, 2023. http://dx.doi.org/10.1063/5.0161520.
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Hartmann, Francis X., J. K. Munro, and D. W. Noid. "Dynamics of a coupled nuclear-electron model In an Intense laser field." In OSA Annual Meeting. Optica Publishing Group, 1987. http://dx.doi.org/10.1364/oam.1987.tus8.
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Energy transfer processes in a simple single particle coupled nuclear-electron model interacting with an intense laser field are studied. In our model, an excited valence proton is bound as an independent particle in a Woods-Saxon potential—its dynamics are characteristic of nuclear motion in the Blatt and Weisskopf single-particle approximation. The electron is bound to the nu clear core in a nonrelativistic treatment by a Coulomb potential—its dynamics are characteristic of single-particle electronic transitions. Initial conditions for the classical trajectories are chosen to be states of the separable Hamiltonian, and the Bohr quantization condition is applied. The spectral analysis method1 is then used to calculate both transition intensities and frequencies for coupled electron-nucleon quantum mechanical transitions. This approach is particularly useful in treating perturbations on the coupled spectra. We have reported2 cases of strong coupling and chaotic motion in a simple model having extreme ionizations. We report here on dynamics of this model system in the presence of an intense laser field.
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Probst, Christof, Sarah Lukas, and Johannes Huwer. "USING AUGMENTED REALITY TO INTRODUCE THE BOHR ATOMIC MODEL IN 3D IN THE CLASSROOM – A STUDY ABOUT LEARNING EFFECTS AND PERCEPTION OF STUDENTS." In 15th International Technology, Education and Development Conference. IATED, 2021. http://dx.doi.org/10.21125/inted.2021.0378.
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Orenstein, J., Benjamin I. Greene, R. R. Millard, and L. R. Williams. "Resonant nonlinear optical response of 1-D excitons." In OSA Annual Meeting. Optica Publishing Group, 1986. http://dx.doi.org/10.1364/oam.1986.thb3.
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The nonlinear optical properties of polymeric semiconductors have recently come under intensive study due to increasing interest in optical signal processing. The nonresonant nonlinear optical constants of polydiacetylene-PTS have previously been well characterized. In this paper we present results on the resonant nonlinear optical response of PTS. One measurement was performed using the transient grating technique. Two 1.97-eV pulses were overlapped at the sample to form an intensity grating. A reflectivity grating developed which was probed by a third time-delayed pulse. The magnitude of the reflectivity change per absorbed photon was extremely large, corresponding to a nonlinear refractive index, n2, of 3 × 10−2 (MW/cm2)−1. The recovery time of the system following pulsed excitation was 2.0 ± 0.2 ps. We interpret our results in terms of a model in which the nonlinear response is entirely due to the dynamics of the singlet exciton in PTS. We describe a straightforward extension of the ideas developed by Schmitt-Rink, Chemla, and Miller for a 2-D exciton system to 1-D.1 Using their "phase-space filling” model, the magnitude of n2 allows us to determine the Bohr radius of the exciton to be 30 Å, which is in excellent agreement with theoretical predictions. In addition we discuss a simple offshoot of this model which gives a good quantitative description of nonresonant response of PTS as well.
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Feglar, Tom, Jason K. Levy, and Tatiana Feglar. "The BOCR and Business Rules Motivation Model." In The International Symposium on the Analytic Hierarchy Process. Creative Decisions Foundation, 2005. http://dx.doi.org/10.13033/isahp.y2005.055.
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HANNAFIOUS, Brian, and Matthias Burkardt. "The Boer-Mulders asymmetry : models and universality." In LIGHT CONE 2008 Relativistic Nuclear and Particle Physics. Sissa Medialab, 2009. http://dx.doi.org/10.22323/1.061.0032.
Full textReports on the topic "Bohr model"
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Tummaruk, Padet, Kakanang Buranaamnuay, Wanpen Adulyanubap, Jinda Singlor, and Mongkol Techakumphu. Development of techniques for freezing boar semen. Chulalongkorn University, 2006. https://doi.org/10.58837/chula.res.2006.91.
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The objective of the present study was to investigate the feasibility of boar semen cryopreservation in Thailand and to investigate factors that could affect the boar semen quality after cryopreservation. Fifteen purebred boars (5 Landrace, 5 Yorkshire and 5 Duroc) from 2 commercial herds in Nakorn-prathom province were used in the experiment. Three ejaculates from each boar were collected with over one-week interval using gloved-hand technique. After collection, the semen was diluted with isothermal Beltsville thawing solution (BTS) extender. Diluted semen was held at 15 °C for 2 h and centrifuged. The supernatant was discarded and the semen precipitant was re-suspended with lactose-egg yolk (LEY) extender. The diluted semen was cool down to 5°C within 90 min. Two parts of semen were mixed with one part of LEY extender with 9% glycerol and 1.5% Equex-STM®. Thereafter, the processed semen was loaded into 0.5 mL straws. The straws were placed in liquid nitrogen (LN2) vapor approximately 3 cm above the level of the LN2 for 20 min and then were plunged into LN2. Thawing was achieved by immersing the straws in water at 50 °C for 12 second. After thawing, the semen was diluted (1:4) with an extender consisting of 95% BTS and 5% LEY extender. The extended thawed semen was incubated in a 38 °C water-bath for 30 min before evaluating the semen quality after thawing. Sperm concentration, individual motility, sperm viability, percentage of normal apical ridge (NAR), sperm plasma membrane function (sHost) and sperm plasma membrane integrity (SYBR) were evaluated. The semen qualities before and after thawing were compared for each boar using paired t-test. Pearson’s correlation was used to evaluate the correlation among all sperm parameters that were measured. Data on individual motility, viability, NAR, sHost positive spermatozoa and SYBR after thawing were analyzed using the General Linear Model (GLM) procedure of the SAS. On average, the sperm concentration of pre-diluted fresh semen was 529.7x106 spz/mL and the sperm concentration of frozen thawed semen was 811x106 spz/mL. The individual motility, the sperm viability, the NAR, the sHost and the SYBR of boar spermatozoa after frozen-thawed were 28%, 36.2%, 26.4%, 18.5% and 30.9%, respectively. All of the sperms parameters measured significantly decreased after frozen and thawed i.e., individual motility decreased by 44.2%, sperm viability decreased by 37.9% and NAR deceased by 59.5%. The individual motility of frozen-thawed spermatozoa was significantly correlated with the sperm viability (P<0.001), the NAR (P<0.02), the sHOST (P<0.001) and the membrane integrity (SYBR) (P<0.001). The higher concentration of frozen-thawed semen resulted in the lower membrane integrity (r=-0.3, P=0.04). Breed of boars and the individual boar within the same breed significantly influenced most of the sperm parameters after being frozen-thawed. The sperm viability of frozen-thawed semen in Duroc and Landrace boars was significantly higher than Yorkshire boars (P<0.05). The membrane integrity of frozen-thawed semen in Landrace boar was significantly higher than Yorkshire boars (P<0.05). In conclusions, the semen cryopreservation of boar could be performed successfully in Thailand with an average concentration of spermatozoa in frozen thawed semen of 811x106 spz/mL, the individual motility of 28% and the sperm viability of 36%. Breed of boars and the individual boar within the same breed significantly influenced most of the sperm parameters after being frozen-thawed.
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Fernández Martín, Andrés, and Juan David Herreño. Equilibrium Unemployment During Financial Crises. Inter-American Development Bank, 2013. http://dx.doi.org/10.18235/0011449.
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Financial crises in both emerging and developed economies have been characterized by large output drops and spikes in unemployment and interest rates. To account for these stylized facts this paper builds a business cycle model where financial and la- bor market frictions interact as occasionally binding borrowing constraints and search frictions. The model is calibrated to a Sudden Stop-prone emerging economy and also to some peripheral European economies in the recent crisis. The model accounts for unemployment dynamics both during crises and at regular business cycle frequencies. The paper also assesses the welfare implications of policies that reduce real minimum wages during crises.
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Yadav, Mukesh, and Deepika Jha. Re-Examine the Model to Manage Revenue Court Cases in Uttar Pradesh. Indian Institute for Human Settlements, 2022. http://dx.doi.org/10.24943/remmrccup03.2022.
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The Board of Revenue (BoR), Government of Uttar Pradesh, with the technical support of the National Informatics Centre (NIC)–UP, launched an online portal—Revenue Court Computerised Management System (RCCMS)—in the year 2013. Given the services offered by the portal, it is quite evident that the RCCMS has improved the transparency and efficiency in the functioning of revenue courts in Uttar Pradesh. Based on a study conducted by the Indian Institute for Human Settlements (IIHS), the team has found that this portal has the scope for further improvement, despite its technological advancements. This policy brief compares the national level portal (the Supreme Court) and one state (Madhya Pradesh) for such improvisation.
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Ginis, Isaac, Deborah Crowley, Peter Stempel, and Amanda Babson. The impact of sea level rise during nor?easters in New England: Acadia National Park, Boston Harbor Islands, Boston National Historical Park, and Cape Cod National Seashore. National Park Service, 2024. http://dx.doi.org/10.36967/2304306.
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This study examines the potential impact of sea level rise (SLR) caused by climate change on the effects of extratropical cyclones, also known as nor?easters, in four New England coastal parks: Acadia National Park (ACAD), Boston Harbor Islands National Recreation Area (BOHA), Boston National Historical Park (BOST) and Cape Cod National Seashore (CACO). A multi-method approach is employed, including a literature review, observational data analysis, coupled hydrodynamic-wave numerical modeling, 3D visualizations, and communication of findings. The literature review examines previous studies of nor?easters and associated storm surges in New England and SLR projections across the study domain due to climate change. The observational data analysis evaluates the characteristics of nor?easters and their effects, providing a basis for validating the model. Numerical modeling is performed using the Advanced Circulation (ADCIRC) model, coupled with the Simulating Waves in the Nearshore (SWAN) model to simulate storm surges and waves. The model was validated against available observations and demonstrated its ability to simulate water levels, inland inundation, and wave heights in the study area with high accuracy. The validated model was used to simulate three powerful nor?easters (April 2007, January 2018, and March 2018) and each storm was simulated for three sea levels, (1) a baseline mean sea level representative of the year 2020, as well as with a (2) 1 ft of SLR and (3) 1 m of SLR. Analysis of the model output was used to assess the vulnerability of the parks to nor?easters by examining peak impacts in the park areas. Additional simulations were conducted to evaluate the role of waves in predicting peak water levels and the impact of inlet configurations on storm surges within coastal embayments behind the barrier beach systems in the southern Cape Cod region. The project developed maps, three-dimensional visualizations, and an interpretive film to assist the parks in planning for resource management, maintenance, emergency management, visitor access, safety, education, and outreach. These tools provide a better understanding of the potential impacts of nor?easters and SLR and enable the parks to better prepare for future storms.
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Landau, Sergei Yan, John W. Walker, Avi Perevolotsky, Eugene D. Ungar, Butch Taylor, and Daniel Waldron. Goats for maximal efficacy of brush control. United States Department of Agriculture, 2008. http://dx.doi.org/10.32747/2008.7587731.bard.
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Background. Brush encroachment constitutes a serious problem in both Texas and Israel. We addressed the issue of efficacy of livestock herbivory - in the form of goat browsing - to change the ecological balance to the detriment of the shrub vegetation. Shrub consumption by goats is kept low by plant chemical defenses such as tannins and terpenes. Scientists at TAES and ARO have developed an innovative, cost-effective methodology using fecal Near Infrared Spectrometry to elucidate the dietary percentage of targeted, browse species (terpene-richredberry and blueberry juniper in the US, and tannin-rich Pistacialentiscus in Israel) for a large number of animals. The original research objectives of this project were: 1. to clarify the relative preference of goat breeds and the individual variation of goats within breeds, when consuming targeted brush species; 2. to assess the heritability of browse intake and validate the concept of breeding goat lines that exhibit high preference for chemically defended brush, using juniper as a model; 3. to clarify the relative contributions of genetics and learning on the preference for target species; 4. to identify mechanisms that are associated with greater intake of brush from the two target species; 5. to establish when the target species are the most vulnerable to grazing. (Issue no.5 was addressed only partly.) Major conclusions, solutions, achievements: Both the Israel and US scientists put significant efforts into improving and validating the technique of Fecal NIRS for predicting the botanical composition of goat diets. Israeli scientists validated the use of observational data for calibrating fecal NIRS, while US scientists established that calibrations could be used across animals differing in breed and age but that caution should be used in making comparisons between different sexes. These findings are important because the ability to select goat breeds or individuals within a breed for maximal efficiency of brush control is dependent upon accurate measurement of the botanical composition of the diet. In Israel it was found that Damascus goats consume diets more than twice richer in P. lentiscus than Mamber or Boer goats. In the US no differences were found between Angora and Boer cross goats but significant differences were found between individuals within breeds in juniper dietary percentage. In both countries, intervention strategies were found that further increased the consumption of the chemically defended plant. In Israel feeding polyethylene glycol (PEG, MW 4,000) that forms high-affinity complexes with tannins increased P. lentiscus dietary percentage an average of 7 percentage units. In the US feeding a protein supplement, which enhances rates of P450-catalyzed oxidations and therefore the rate of oxidation of monoterpenes, increased juniper consumption 5 percentage units. However, the effects of these interventions were not as large as breed or individual animal effects. Also, in a wide array of competitive tannin-binding assays in Israel with trypsin, salivary proteins did not bind more tannic acid or quebracho tannin than non-specific bovine serum albumin, parotid saliva did not bind more tannins than mixed saliva, no response of tannin-binding was found to levels of dietary tannins, and the breed effect was of minor importance, if any. These fundings strongly suggest that salivary proteins are not the first line of defense from tannin astringency in goats. In the US relatively low values for heritability and repeatability for juniper consumption were found (13% and 30%, respectively), possibly resulting from sampling error or non-genetic transfer of foraging behavior, i.e., social learning. Both alternatives seem to be true as significant variation between sequential observations were noted on the same animal and cross fostering studies conducted in Israel demonstrated that kids raised by Mamber goats showed lower propensity to consume P. lentiscus than counterparts raised by Damascus goats.