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121.
122.
Murad S 《The Journal of chemical physics》2011,134(11):114504
Molecular simulations have been carried out using the method of molecular dynamics to investigate the role of external electric fields on the ion mobility, drift velocity, and drift-diffusion rate of ions in aqueous electrolyte solutions. These properties are critical for a range of processes including electrodialysis, electro-deionization, electrophoresis, and electroosmosis. Our results show that external electric fields relax the hydrated ion structure at significantly larger time scales (between 300 and 800 ps), than most other relaxation processes in solutions (generally of the order of 1 ps). Previous studies that did not account for the much longer relaxation times did not observe this behavior for ions even with very high electric fields. External electric fields must also overcome several (at least two or more) activation energy barriers to significantly change the structure of hydrated ions. As a result, the dynamic behavior changes almost in bands as a function of electric field strengths, rather than linearly. Finally, the effect of the field is much less dramatic on water than the ions. Thus electric fields will be of more significance in processes that involve the transport of ions (such as electro-deionization) than the transport of water (electroosmosis). 相似文献
123.
We study the dynamical chiral symmetry breaking/restoration for various numbers of light quarks flavors \begin{document}$ N_f $\end{document} ![]()
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and colors \begin{document}$ N_c $\end{document} ![]()
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using the Nambu-Jona-Lasinio (NJL) model of quarks in the Schwinger-Dyson equation framework, dressed with a color-flavor dependence of effective coupling. For fixed \begin{document}$ N_f = 2 $\end{document} ![]()
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and varying \begin{document}$ N_c $\end{document} ![]()
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, we observe that the dynamical chiral symmetry is broken when \begin{document}$ N_c $\end{document} ![]()
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exceeds its critical value \begin{document}$ N^{c}_{c}\approx2.2 $\end{document} ![]()
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. For a fixed \begin{document}$ N_c = 3 $\end{document} ![]()
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and varying \begin{document}$ N_f $\end{document} ![]()
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, we observe that the dynamical chiral symmetry is restored when \begin{document}$ N_f $\end{document} ![]()
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reaches its critical value \begin{document}$ N^{c}_{f}\approx8 $\end{document} ![]()
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. Strong interplay is observed between \begin{document}$ N_c $\end{document} ![]()
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and \begin{document}$ N_f $\end{document} ![]()
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, i.e., larger values of \begin{document}$ N_c $\end{document} ![]()
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tend to strengthen the dynamical generated quark mass and quark-antiquark condensate, while higher values of \begin{document}$ N_f $\end{document} ![]()
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suppress both parameters. We further sketch the quantum chromodynamics (QCD) phase diagram at a finite temperature T and quark chemical potential μ for various \begin{document}$ N_c $\end{document} ![]()
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and \begin{document}$ N_f $\end{document} ![]()
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. At finite T and μ, we observe that the critical number of colors \begin{document}$ N^{c}_c $\end{document} ![]()
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is enhanced, whereas the critical number of flavors \begin{document}$ N^{c}_f $\end{document} ![]()
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is suppressed as T and μ increase. Consequently, the critical temperature \begin{document}$ T_c $\end{document} ![]()
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, \begin{document}$ \mu_c $\end{document} ![]()
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, and co-ordinates of the critical endpoint \begin{document}$ (T^{E}_c,\mu^{E}_c) $\end{document} ![]()
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in the QCD phase diagram are enhanced as \begin{document}$ N_c $\end{document} ![]()
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increases and suppressed when \begin{document}$ N_f $\end{document} ![]()
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increases. Our findings agree with the lattice QCD and Schwinger-Dyson equations predictions. 相似文献
124.
Abstract A Wick-Itô formula for Gaussian processes is obtained. This is a change of variables formula, which is to Wick-Itô integrals what the usual Itô formula is to Itô integrals. The conditions are weak enough to allow processes with infinite quadratic variation. They are satisfied by fractional Brownian motion with parameter 1/4 < H < 1. 相似文献
125.
Murad Jurdak 《ZDM》2014,46(7):1025-1037
This paper aims at identifying and understanding how and to what extent socioeconomic and cultural factors mediate mathematics achievement and between-school equity in mathematics education among countries. First, under the assumption that equity and quality of education are independent constructs, the construct of equity-in-quality in mathematics education is developed. Second, the 18 countries that were identified in the previous work of the author Jurdak in (Toward equity in quality in mathematics education. Springer, New York, 2009) as being diverse in mathematics education will serve as study cases to illustrate, compare, and contrast the mediatory role of socio-economic and cultural factors in mathematics achievement and between-school equity in mathematics education. The results show that the differences in mathematics achievement and between-school equity in mathematics education at the country level are associated with, and can be accounted for in some cases, by socioeconomic and cultural factors. 相似文献
126.
Liaqat Ali Murad Ahmad Rameez-ul-Islam Muhammad Imran Manzoor Ikram Iftikhar Ahmad 《Annalen der Physik》2024,536(4):2300277
The quantized momentum eigenstates of neutral atoms offer high resistance to decoherence and thus suggests a viable alternative for quantum informatics tasks including teleportation. In this work, a scheme is suggested to teleport an unknown superposition of two distinct external momentum states of a neutral atom onto the similar momentum states of a distant atom at the receiving end through the off-resonant atomic Bragg diffraction (ABD). In order to teleport this unknown state from the sender, that is, Alice, to the receiver, that is, Bob, a pre-existing entangled link formed through a high-Q cavity at Alice's end and momentum states of a neutral atom at the Bob's end are utilized. Further, while citing the realistic experimental parameters, it is demonstrated that the proposal can easily be implemented experimentally under the prevailing cavity-QED atom-field research scenario. The proposal is also generalized to cover the teleportation of the multipartite entangled momenta states and the case of multipartite GHZ entangled states is elucidated in details. However, the procedure is generic and can be extended to cover the teleportation schematics for any arbitrary atomic momenta states. 相似文献
127.
Rakesh K. Sindhu Rishu Verma Twinkle Salgotra Md. Habibur Rahman Muddaser Shah Rokeya Akter Waheed Murad Sidra Mubin Parveen Bibi Safaa Qusti Eida M. Alshammari Gaber El-Saber Batiha Micha Tomczyk Hayder M. Al-kuraishy 《Molecules (Basel, Switzerland)》2021,26(17)
Breast cancer persists as a diffuse source of cancer despite persistent detection and treatment. Flavonoids, a type of polyphenol, appear to be a productive option in the treatment of breast cancer, because of their capacity to regulate the tumor related functions of class of compounds. Plant polyphenols are flavonoids that appear to exhibit properties which are beneficial for breast cancer therapy. Numerous epidemiologic studies have been performed on the dynamic effect of plant polyphenols in the prevention of breast cancer. There are also subclasses of flavonoids that have antioxidant and anticarcinogenic activity. These can regulate the scavenging activity of reactive oxygen species (ROS) which help in cell cycle arrest and suppress the uncontrolled division of cancer cells. Numerous studies have also been performed at the population level, one of which reported a connection between cancer risk and intake of dietary flavonoids. Breast cancer appears to show intertumoral heterogeneity with estrogen receptor positive and negative cells. This review describes breast cancer, its various factors, and the function of flavonoids in the prevention and treatment of breast cancer, namely, how flavonoids and their subtypes are used in treatment. This review proposes that cancer risk can be reduced, and that cancer can be even cured by improving dietary intake. A large number of studies also suggested that the intake of fruit and vegetables is associated with reduced breast cancer and paper also includes the role and the use of nanodelivery of flavonoids in the healing of breast cancer. In addition, the therapeutic potential of orally administered phyto-bioactive compounds (PBCs) is narrowed because of poor stability and oral bioavailability of compounds in the gastrointestinal tract (GIT), and solubility also affects bioavailability. In recent years, creative nanotechnology-based approaches have been advised to enhance the activity of PBCs. Nanotechnology also offers the potential to become aware of disease at earlier stages, such as the detection of hidden or unconcealed metastasis colonies in patients diagnosed with lung, colon, prostate, ovarian, and breast cancer. However, nanoformulation-related effects and safety must not be overlooked. This review gives a brief discussion of nanoformulations and the effect of nanotechnology on herbal drugs. 相似文献
128.
In this paper, we study almost sure central limit theorems for sequences of functionals of general Gaussian fields. We apply our result to non-linear functions of stationary Gaussian sequences. We obtain almost sure central limit theorems for these non-linear functions when they converge in law to a normal distribution. 相似文献
129.
Xuerui Wang Yuting Zhang Xiaoyu Wang Eduardo Andres‐Garcia Peng Du Lorena Giordano Lin Wang Zhou Hong Xuehong Gu Sohail Murad Freek Kapteijn 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(43):15664-15671
Xe is only produced by cryogenic distillation of air, and its availability is limited by the extremely low abundance. Therefore, Xe recovery after usage is the only way to guarantee sufficient supply and broad application. Herein we demonstrate DD3R zeolite as a benchmark membrane material for CO2/Xe separation. The CO2 permeance after an optimized membrane synthesis is one order magnitude higher than for conventional membranes and is less susceptible to water vapour. The overall membrane performance is dominated by diffusivity selectivity of CO2 over Xe in DD3R zeolite membranes, whereby rigidity of the zeolite structure plays a key role. For relevant anaesthetic composition (<5 % CO2) and condition (humid), CO2 permeance and CO2/Xe selectivity stabilized at 2.0×10?8 mol m?2 s?1 Pa?1 and 67, respectively, during long‐term operation (>320 h). This endows DD3R zeolite membranes great potential for on‐stream CO2 removal from the Xe‐based closed‐circuit anesthesia system. The large cost reduction of up to 4 orders of magnitude by membrane Xe‐recycling (>99+%) allows the use of the precious Xe as anaesthetics gas a viable general option in surgery. 相似文献
130.
Summary Normalized quadratic forms of moving averages converge to double Wiener-Itô integrals if the summands are sufficiently dependent. This result extends to sums of bivariate Appell polynomials of arbitrary degree.This research was supported at Boston University by the National Science Foundation grant DMS-88-05627 and by the AFSOR grant 89-0115 相似文献