Whether or not the Maxwell theory works on the atomic level

2021 ◽  
pp. 2150166
Author(s):  
J. T. Wang ◽  
Jiangdi Fan ◽  
Aaron X. Kan

In this paper, we have studied the Maxwell radiation from the electron orbiting the nucleus in an atom such as hydrogen atom. The orbiting electron is thought as two oscillating dipoles: one on [Formula: see text]-axis and the other on [Formula: see text]-axis with the same frequency. We have derived the electromagnetic wave and calculated powers of the radiation from these two oscillating dipoles, and then determined the time period it takes for the electron to change its energy levels from [Formula: see text] to [Formula: see text] due to the Maxwell radiation. Compared the time period due to the Maxwell radiation with the time period from the uncertainty principle, it is found that the two time periods are different from each other by about nine orders of magnitude. So, we are led to believe that the Maxwell theory could not be used in the quantum photo emission by the electron in an atom. Thus, we suggest that the quantum photo emission by the electron in an atom may be photon tunneling from the electron [Formula: see text] in an atom.

Nativa ◽  
2019 ◽  
Vol 7 (4) ◽  
pp. 420
Author(s):  
Gustavo Gomes Figueiredo ◽  
Andressa Thaís Porazzi Bortolini ◽  
Diego Martins Stangerlin ◽  
Elisangela Pariz ◽  
Denise Dos Santos Oliveira

O tratamento de acetilação é um processo químico de modificação da madeira que visa melhorar algumas das suas propriedades, agregando maior valor ao produto final. Deste modo, objetivou-se avaliar as propriedades físicas, mecânicas e biológicas da madeira acetilada de Trattinnickia burserifolia Mart. (amescla). Os tratamentos de acetilação efetuaram-se por imersão em anidrido acético durante dois períodos de tempo – 3 e 6 horas – com temperatura constante de 80ºC. O tempo de tratamento de acetilação influenciou significativamente no ganho de massa da madeira, sendo verificados os maiores valores para o tratamento de 6 horas. Por outro lado, a massa específica não foi influenciada significativamente pelo tempo de tratamento. Na absorção em água e retratibilidade volumétrica, após o tempo de 2 horas, 24 horas e saturação total, o tratamento de 6 horas foi o mais eficaz. Na propriedade mecânica de dureza Rockwell, evidenciou-se que a madeira tratada apresentou maiores valores de resistência mecânica. A acetilação da madeira de amescla proporcionou aumento da resistência biológica ao ataque de cupins xilófagos.Palavras-chave: modificação química; qualidade da madeira; madeira tropical. TECHNOLOGICAL CHARACTERIZATION OF AMESCLA WOOD SUBMITTED TO ACETYLATION TREATMENT ABSTRACT: The acetylation treatment is a chemical process of wood modification that aims to improve some of its properties, adding more value for the final product. In this way, this study aimed to evaluate the physical, mechanical and biological properties of the amescla wood. The acetylation treatment was performed by immersion in acetic anhydride over two time periods – 3 and 6 hours – with a constant temperature of 80°C. The time period of acetylation influenced significantly in the WPG (weight percentual gain) of the wood, and the highest values were noticed for the 6 hours treatment. On the other hand, the density was not significantly influenced by the treatment time. In water absorption and volumetric swelling after 2 hours, 24 hours and full saturation, the 6 hours treatment was most effective. The mechanical property of Rockwell hardness demonstrated that the treated wood had higher mechanical strength values. The acetylation of amescla wood has provided increased biological resistance to xylophagous termites.Keywords: chemical modification; wood quality; tropical wood.


Author(s):  
Nathalie Deruelle ◽  
Jean-Philippe Uzan

This chapter takes a look at the energy radiated by a single charge. After deriving the Larmor formulas, it studies the paradigmatic cases of the radiation of a linearly accelerated charge. Next, it turns to the synchrotron radiation of a charge in circular motion. Finally, the chapter considers the radiation of a charge accelerated by an electromagnetic wave—Thomson scattering, which is when the energy is radiated to infinity. In addition, the chapter also reveals that the hydrogen atom as described by the Rutherford model of an electron orbiting a proton is highly unstable in Maxwell theory.


2019 ◽  
Vol 14 (2) ◽  
Author(s):  
Kjell Hausken ◽  
Mthuli Ncube

We consider revolutions and civil war involving an incumbent, a challenger, and the population. Revolutions are classified into eight outcomes. In four outcomes incumbent repression occurs (viewed as providing sub-threshold benefits such as public goods to the population). Accommodation occurs in the other four outcomes (benefits provision above a threshold). The incumbent and challenger fight each other. The incumbent may win and retain power or else lose, thereby causing standoff or coalition. In a standoff, which is costly, no one backs down and uncertainty exists about who is in power. In a coalition, which is less costly, the incumbent and challenger cooperate, compromise, and negotiate their differences. If the population successfully revolts against the incumbent, the challenger replaces the incumbent. Eighty-seven revolutions during 1961–2011, including the recent Arab spring revolutions, are classified into the eight outcomes. When repressive, the incumbent loses 46 revolutions, remains in power through 21 revolutions, and builds a coalition after 12 revolutions. When accommodative, the incumbent loses seven revolutions and builds a coalition after one revolution. The 87 revolutions are classified across geographic regions and by time-period.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Constantin-Cristian Topriceanu ◽  
James C. Moon ◽  
Rebecca Hardy ◽  
Nishi Chaturvedi ◽  
Alun D. Hughes ◽  
...  

AbstractA frailty index (FI) counts health deficit accumulation. Besides traditional risk factors, it is unknown whether the health deficit burden is related to the appearance of cardiovascular disease. In order to answer this question, the same multidimensional FI looking at 45-health deficits was serially calculated per participant at 4 time periods (0–16, 19–44, 45–54 and 60–64 years) using data from the 1946 Medical Research Council (MRC) British National Survey of Health and Development (NSHD)—the world’s longest running longitudinal birth cohort with continuous follow-up. From these the mean and total FI for the life-course, and the step change in deficit accumulation from one time period to another was derived. Echocardiographic data at 60–64 years provided: ejection fraction (EF), left ventricular mass indexed to body surface area (LVmassi, BSA), myocardial contraction fraction indexed to BSA (MCFi) and E/e′. Generalized linear models assessed the association between FIs and echocardiographic parameters after adjustment for relevant covariates. 1375 participants were included. For each single new deficit accumulated at any one of the 4 time periods, LVmassi increased by 0.91–1.44% (p < 0.013), while MCFi decreased by 0.6–1.02% (p < 0.05). A unit increase in FI at age 45–54 and 60–64, decreased EF by 11–12% (p < 0.013). A single health deficit step change occurring between 60 and 64 years and one of the earlier time periods, translated into higher odds (2.1–78.5, p < 0.020) of elevated LV filling pressure. Thus, the accumulation of health deficits at any time period of the life-course associates with a maladaptive cardiac phenotype in older age, dominated by myocardial hypertrophy and poorer function.


2020 ◽  
pp. 135245852091049 ◽  
Author(s):  
Kelsi A Smith ◽  
Sarah Burkill ◽  
Ayako Hiyoshi ◽  
Tomas Olsson ◽  
Shahram Bahmanyar ◽  
...  

Background: People with multiple sclerosis (pwMS) have increased comorbid disease (CMD) risk. Most previous studies have not considered overall CMD burden. Objective: To describe lifetime CMD burden among pwMS. Methods: PwMS identified using Swedish registers between 1968 and 2012 ( n = 25,476) were matched by sex, age, and county of residence with general-population comparators ( n = 251,170). Prevalence, prevalence ratios (PRs), survival functions, and hazard ratios by MS status, age, and time period compared seven CMD: autoimmune, cardiovascular, depression, diabetes, respiratory, renal, and seizures. Results: The magnitude of the PRs for each CMD and age group decreased across time, with higher PRs in earlier time periods. Before 1990, younger age groups had higher PRs, and after 1990, older age groups had higher PRs. Male pwMS had higher burden compared with females. Overall, renal, respiratory, and seizures had the highest PRs. Before 2001, 50% of pwMS received a first/additional CMD diagnosis 20 years prior to people without MS, which reduced to 4 years after 2001. PwMS had four times higher rates of first/additional diagnoses in earlier time periods, which reduced to less than two times higher in recent time periods compared to people without MS. Conclusion: Swedish pwMS have increased CMD burden compared with the general population, but this has reduced over time.


2006 ◽  
Vol 15 (06) ◽  
pp. 1263-1271 ◽  
Author(s):  
A. SOYLU ◽  
O. BAYRAK ◽  
I. BOZTOSUN

In this paper, the energy eigenvalues of the two dimensional hydrogen atom are presented for the arbitrary Larmor frequencies by using the asymptotic iteration method. We first show the energy eigenvalues for the case with no magnetic field analytically, and then we obtain the energy eigenvalues for the strong and weak magnetic field cases within an iterative approach for n=2-10 and m=0-1 states for several different arbitrary Larmor frequencies. The effect of the magnetic field on the energy eigenvalues is determined precisely. The results are in excellent agreement with the findings of the other methods and our method works for the cases where the others fail.


1974 ◽  
Vol 20 (10) ◽  
pp. 1403-1409 ◽  
Author(s):  
B. G. Foster ◽  
Mary O. Hanna

Aeromonas proteolytica was grown for various time periods in nutrient broth, tryptic soy broth, a semisynthetic medium, and 1 and 5% peptone under different conditions involving temperature and in continuous shake and stationary flasks. The cell-free culture filtrates were tested for hemolytic, endopeptidase, and dermonecrotic activity and optimal growth conditions for their production were determined. The dermonecrotic activity and endopeptidase activity was found to be parallel in all tests, while hemolysin was independent of the other two. Studies on the thermal stability of the culture filtrate revealed that hemolysin and dermonecrotic and endopeptidase activity were destroyed at 70 °C for 30 min. Fractionation of the filtrate by Sephadex G-200 resolved three peaks at 280 nm. Peak I was inactive; peak II contained endopeptidase and dermonecrotic and hemolytic activity; peak III contained pigment and hemolysin. Evidence is presented that the endopeptidase and dermonecrotic substance found in the cell-free filtrates of A. proteolytica grown medium appear at the same time and thus may be the same entity.


2018 ◽  
Vol 4 ◽  
pp. 237802311881180 ◽  
Author(s):  
Jonathan J. B. Mijs

In this figure I describe the long trend in popular belief in meritocracy across the Western world between 1930 and 2010. Studying trends in attitudes is limited by the paucity of survey data that can be compared across countries and over time. Here, I show how to complement survey waves with cohort-level data. Repeated surveys draw on a representative sample of the population to describe the typical beliefs held by citizens in a given country and period. Leveraging the fact that citizens surveyed in a given year were born in different time-periods allows for a comparison of beliefs across birth cohorts. The latter overlaps with the former, but considerably extends the time period covered by the data. Taken together, the two measures give a “triangulated” longitudinal record of popular belief in meritocracy. I find that in most countries, popular belief in meritocracy is (much) stronger for more recent periods and cohorts.


2018 ◽  
Vol 2018 ◽  
pp. 1-11 ◽  
Author(s):  
Chuen-Chang Lin ◽  
You-Lun Shen ◽  
An-Na Wu

Carbon nanotubes/graphene composites are directly grown on nickel foil without additional catalysts by chemical vapor deposition (CVD). Next, the cobalt is deposited on carbon nanotubes/graphene composites by radio frequency (RF) sputtering with different power levels and time periods. Then, the cobalt is transformed into cobalt oxide by annealing. A longer time period of sputtering leads to higher specific capacity. Furthermore, the electrochemical stability of cobalt oxide/carbon nanotubes/graphene composites is higher than that of cobalt oxide.


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