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161.
Sumit Kumar Rai Bhabani Prasad Mandal 《The European Physical Journal C - Particles and Fields》2009,63(2):323-330
We study the field/antifield formulation of pure Yang Mills theory in the framework of the finite field dependent BRST transformation. We show that the generating functionals corresponding to different solutions of the quantum master equation are connected through the finite field dependent BRST transformations. We establish this result with the help of several explicit examples. 相似文献
162.
Shubhra Singh Shiv Prasad H. P. Gupta Sumit Singhal Atul K. Gupta Anil Kumar 《Applied biochemistry and biotechnology》2012,166(7):1814-1830
The present study characterized the glycoproteins synthesized by buffalo oviduct. Scanning electron microscopy analyses of
the ampullary and isthmic segments of cyclic and acyclic buffaloes showed ultrastructural variations in ciliated and nonciliated
cells. Mucosal proteins were extracted by scrapping of different segments of oviduct and, after centrifugation, the remainder
tissues were subjected to establish primary cell culture system of oviduct epithelial cells and conditioned media were prepared.
Time- and concentration-dependent effects of trypsinization on the establishment of primary monolayer culture showed that
0.25% trypsin for 1–2 min at 37 °C were the optimal conditions. Total protein content in oviductal tissues and conditioned
media was quantified and analyzed by SDS-PAGE which showed marked variation in different segments of the oviduct. Western
blot analysis revealed five major oviduct-specific glycoproteins (OGPs) in cyclic oviduct (ampulla and isthmus) with Mw 180, 95, 75, 66 and 35 kDa in the oviduct extract and two glycoproteins with Mw 95 and 66 kDa in conditioned media. However, in acyclic oviduct (ampulla and isthmus), three glycoproteins were immunostained
with Mw 180, 95 and 66 kDa in the oviduct extract and one glycoprotein with Mw 66 kDa in conditioned media. Indirect Enzyme-Linked Immuno Sorbent Assay (ELISA) results showed significant differences of
OGPs in different segments of cyclic and acyclic buffaloes and, thus, indicative of segmental variation in the synthesis and
secretion of glycoproteins. Oviductal extract secretes more amounts of OGPs as compared to the conditioned medium. The role
of these OGPs may be defined and exploited for influencing the fertilization process and/or subsequent embryonic development. 相似文献
163.
In this study, we have explored the conformational landscape of the indole···furan dimer in a supersonic jet by using resonant two-photon ionization (R2PI) and IR-UV double-resonance spectroscopic techniques combined with dispersion-corrected density functional theory (DFT) calculations. Only one conformer of the dimer has been observed in the experiment. DFT/B97-D level calculation shows that N-H···π hydrogen-bonded conformer (T') is energetically more stable than the N-H···O hydrogen-bonded conformer (HB). Natural bond orbital (NBO) calculation also shows that the hydrogen-bonding interaction in the HB conformer is very weak. Finally, the structure of the observed dimer has been determined to be tilted T-shaped N-H···π hydrogen-bonded (T') from very excellent agreement between experimental and theoretical N-H stretch frequency. The most significant finding of this study is the first-time observation of a N-H···π bound conformer of a dimer, which wins over a conventional hydrogen-bonded conformer of the dimer. 相似文献
164.
Sumit Kumar Anshu Sharma Balram Tripathi Subodh Srivastava Shweta Agrawal M. Singh Kamlendra Awasthi Y.K. Vijay 《Micron (Oxford, England : 1993)》2010,41(7):909-914
The multi-walled carbon nanotube (MWCNT) dispersed polymethylmethacrylate (PMMA) composite membranes have been prepared for hydrogen gas permeation application. Composite membranes are characterized by Raman spectroscopy, optical microscopy, X-ray diffraction, electrical measurements and gas permeability measurements. The effect of electric field alignment of MWCNT in PMMA matrix on gas permeation has been studied for hydrogen gas. The permeability measurements indicated that the electrically aligned MWCNT in PMMA has shown almost 2 times higher permeability for hydrogen gas as compare to randomly dispersed MWCNT in PMMA. The enhancement in permeability is explained on the basis of well aligned easy channel provided by MWCNT in electrically aligned sample. The effect of thickness of membrane on the gas permeability also studied and thickness of about 30 μm found to be optimum thickness for fast hydrogen gas permeates. 相似文献
165.
The ordered pair (T,I) of two self-maps of a metric space (X,d) is called a Banach operator pair if the set F(I) of fixed points of I is T-invariant i.e. T(F(I))⊆F(I). Some common fixed point theorems for a Banach operator pair and the existence of common fixed points of best approximation are presented in this paper. The results prove, generalize and extend some results of Al-Thagafi [M.A. Al-Thagafi, Common fixed points and best approximation, J. Approx. Theory 85 (1996) 318-323], Carbone [A. Carbone, Applications of fixed point theorems, Jnanabha 19 (1989) 149-155], Chen and Li [J. Chen, Z. Li, Common fixed points for Banach operator pairs in best approximations, J. Math. Anal. Appl. 336 (2007) 1466-1475], Habiniak [L. Habiniak, Fixed point theorems and invariant approximation, J. Approx. Theory 56 (1989) 241-244], Jungck and Sessa [G. Jungck, S. Sessa, Fixed point theorems in best approximation theory, Math. Japon. 42 (1995) 249-252], Sahab, Khan and Sessa [S.A. Sahab, M.S. Khan, S. Sessa, A result in best approximation theory, J. Approx. Theory 55 (1988) 349-351], Shahzad [N. Shahzad, Invariant approximations and R-subweakly commuting maps, J. Math. Anal. Appl. 257 (2001) 39-45] and of few others. 相似文献
166.
Oscillatory density profiles (layers) have previously been observed at the free surfaces of liquid metals but not in other isotropic liquids. We have used x-ray reflectivity to study a molecular liquid, tetrakis(2-ethylhexoxy)silane. When cooled to T/Tc approximately 0.25 (well above the freezing point for this liquid), density oscillations appear at the surface. Lateral order within the layers is liquidlike. Our results confirm theoretical predictions that a surface-layered state will appear even in dielectric liquids at sufficiently low temperatures, if not preempted by freezing. 相似文献
167.
Samrat Das Adhikari Sumit K. Dutta Anirban Dutta Amit K. Guria Dr. Narayan Pradhan 《Angewandte Chemie (International ed. in English)》2017,56(30):8746-8750
Doping in perovskite nanocrystals adopts different mechanistic approach in comparison to widely established doping in chalcogenide quantum dots. The fast formation of perovskites makes the dopant insertions more competitive and challenging. Introducing alkylamine hydrochloride (RNH3Cl) as a promoting reagent, precise controlled doping of MnII in CsPbCl3 perovskite nanocrystals is reported. Simply, by changing the amount of RNH3Cl, the Mn incorporation and subsequent tuning in the excitonic as well as Mn d–d emission intensities are tailored. Investigations suggested that RNH3Cl acted as the chlorinating source, controlled the size, and also helps in increasing the number of particles. This provided more opportunity for Mn ions to take part in reaction and occupied the appropriate lattice positions. Carrying out several reactions with varying reaction parameters, the doping conditions are optimized and the role of the promoting reagent for both doped and undoped systems are compared. 相似文献
168.
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170.
Inside Back Cover: Introducing Chirality into Nonionic Dendritic Amphiphiles and Studying Their Supramolecular Assembly (Chem. Eur. J. 16/2016) 下载免费PDF全文