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71.
We show that experimental data on inclusive neutrino reactions can be used to obtain general bounds on the coupling constants
of the isovector part of the hadronic weak neutral current provided this isovector current is related to the charged current
by isospin rotation. These bounds are free from the assumption of a specific model for the neutral current as well as any
dynamical assumption on the hadronic structure functions. We derive upper bounds on the coupling constants which involve only
the cross sections for isospin-averaged nucleon target as well as lower bounds which require a knowledge of the cross sections
for proton and neutron separately. 相似文献
72.
The orientation of fiber direction in layers and the number of layers of composites play the major role in determining the
strength and stiffness. Thus, the basic design problem is to determine the optimum stacking sequence of the composite laminate.
Many methods are available at present for the design optimization of structural systems. However, these methods are based
on mathematical programming techniques involving the gradient search and the direct search. These methods assume that the
variables are continuous. In this paper, a different search and optimization algorithm, known as a Genetic Algorithm (GA),
has been successfully applied to obtain the optimum fiber orientation of multilayered shells, which considers the angle of
fiber orientation as a discrete variable. The principle of GA is applied to obtain optimum layers and the orientation of fibers
of stiffened shells for both the symmetric and antisymmetric orientations of fibers for dynamic analysis. Shells composed
of two to nine layers without stiffeners, with one stiffener, and with two stiffeners for a single as well as different materials
are analyzed and the maximum frequency for each population is computed using the FEAST-C software.
Submitted to the 11th International Conference on Mechanics of Composite Materials (Riga, June 11–15, 2000).
Published in Mekhanika Kompozitnykh Materialov, Vol. 36, No. 2, pp. 271–278, March–April, 2000. 相似文献
73.
Sensing of Pyrophosphate Anion by a Fluorescent Zn(II) Complex Bearing Acenaphthene Imidazole Moiety
Kavitha Venkatachalam Chitra Krishnamoorthy Gomathi Asaithambi Dhivya Rajasekaran Viswanathamurthi Periasamy 《Journal of Analytical Chemistry》2022,77(7):882-892
Journal of Analytical Chemistry - Acenaphthene imidazole ligand (AIMP) reacted with zinc acetate for the synthesis of Zn-AIMP complex which was used to detect pyrophosphate (PPi) ions in the... 相似文献
74.
Dr. Rajasekaran Ganesan Mansour A. Dughbaj Lisa Ramirez Steven Beringer Dr. Teshome L. Aboye Prof. Alexander Shekhtman Prof. Paul M. Beringer Prof. Julio A. Camarero 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(49):12702-12708
The search for novel antimicrobial agents to combat microbial pathogens is intensifying in response to the rapid development of drug resistance to current antibiotic therapeutics. Respiratory failure and septicemia are the leading causes of mortality among hospitalized patients. Here, the development of a novel engineered cyclotide with effective broad-spectrum antibacterial activity against several ESKAPE bacterial strains and clinical isolates is reported. The most active antibacterial cyclotide was extremely stable in serum, showed little hemolytic activity, and provided protection in vivo in a murine model of P. aeruginosa peritonitis. These results highlight the potential of the cyclotide scaffold for the development of novel antimicrobial therapeutic leads for the treatment of bacteremia. 相似文献
75.
Zhou C Rajasekaran PR Wolff J Li X Kohli P 《Langmuir : the ACS journal of surfaces and colloids》2010,26(22):17726-17732
We demonstrate conical pores etched in tracked glass chips for fabricating patterns at the micrometer scale. Highly fluorescent patterns based on photopolymerization of diacetylene films were formed by irradiating UV light through conical pores called "photo-pens". The properties of photopens were investigated through experiments, finite-difference-time-domain (FDTD) simulations and numerical calculations based on Fresnel equations. We show that the pattern dimensions are easily controlled by adjusting the exposure time. Thus, patterns with a range of dimensions can be fabricated without any need of changes in the pore diameter. Parallel patterning was also demonstrated by simultaneously exposing the films to photons through multiple pores in the chip. Our method provides an inexpensive, versatile, and efficient way for patterning without the use of sophisticated masks. 相似文献
76.
S. Gopinath S. Barathan R. Rajasekaran 《Journal of Thermal Analysis and Calorimetry》2012,110(2):789-792
Single crystals of urea thiourea sodium chloride (UTNC) were grown from aqueous solution by slow evaporation technique. FTIR spectra were recorded to identify the functional groups. The crystals were characterized by recording the powder X-ray diffraction that revealed the crystalline nature of the crystal. The UV?CVis spectral study was carried out to test the optical transmitting property. The second harmonic generation test (SHG) was carried out, and it shows the non-linear nature of the crystal. The thermal stability of the crystal was analyzed by thermogravimetric and differential thermal analysis (TG-DTA). 相似文献
77.
Superdeformed nuclei at high-spin states in several mass regions are investigated within a microscopic approach using cranked Nilsson-Strutinsky formalism to explore the equilibrium deformations in the ground state and their evolution with spin. Shape transition from normal deformed to superdeformed states with increasing spin is studied and a clear picture of shape coexistence is provided. Detailed information on spin, rotational energy, dynamical moment of inertia, and rotational frequency of superdeformed rotational bands is presented and the general features of superdeformed bands in certain mass regions are outlined. Rotational energy and dynamical moment of inertia are compared with available experimental data and the impact of temperature and pairing on superdeformed configuration are discussed. 相似文献
78.
Ponnusamy Sami Thangarajan Durai Anand Mariappan Premanathan Kasi Rajasekaran 《Transition Metal Chemistry》2010,35(8):1019-1025
Glutathione (GSH) undergoes facile electron transfer with vanadium(V)-substituted Keggin-type heteropolyoxometalates,
[ \textPV\textV \textW 1 1 \textO 4 0 ] 4 - [ {\text{PV}}^{\text{V}} {\text{W}}_{ 1 1} {\text{O}}_{ 4 0} ]^{{ 4 { - }}} (HPA1) and
[ \textPV\textV \textV\textV \textW 1 0 \textO 4 0 ] 5 - [ {\text{PV}}^{\text{V}} {\text{V}}^{\text{V}} {\text{W}}_{ 1 0} {\text{O}}_{ 4 0} ]^{{ 5 { - }}} (HPA2). The kinetics of these reactions have been investigated in phthalate buffers spectrophotometrically at 25 °C in aqueous
medium. One mole of HPA1 consumes one mole of GSH and the product is the one-electron reduced heteropoly blue,
[ \textPV\textIV \textW 1 1 \textO 40 ] 5- [ {\text{PV}}^{\text{IV}} {\text{W}}_{ 1 1} {\text{O}}_{ 40} ]^{ 5- } . But in the GSH-HPA2 reaction, one mole of HPA2 consumes two moles of GSH and gives the two-electron reduced heteropoly blue
[ \textPV\textIV \textV\textIV \textW 10 \textO 40 ] 7- [ {\text{PV}}^{\text{IV}} {\text{V}}^{\text{IV}} {\text{W}}_{ 10} {\text{O}}_{ 40} ]^{ 7- } . Both reactions show overall third-order kinetics. At constant pH, the order with respect to both [HPA] species is one and
order with respect to [GSH] is two. At constant [GSH], the rate shows inverse dependence on [H+], suggesting participation of the deprotonated thiol group of GSH in the reaction. A suitable mechanism has been proposed
and a rate law for the title reaction is derived. The antimicrobial activities of HPA1, HPA2 and
[ \textPV\textV \textV\textV \textV\textV \textW 9 \textO 4 0 ] 6 - [ {\text{PV}}^{\text{V}} {\text{V}}^{\text{V}} {\text{V}}^{\text{V}} {\text{W}}_{ 9} {\text{O}}_{ 4 0} ]^{{ 6 { - }}} (HPA3) against MRSA were tested in vitro in combination with vancomycin and penicillin G. The HPAs sensitize MRSA towards
penicillin G. 相似文献
79.
Nair V Poonoth M Vellalath S Suresh E Thirumalai R 《The Journal of organic chemistry》2006,71(23):8964-8965
A novel protocol for the annulation of tropone to enals involving nucleophilic heterocyclic carbene (NHC) catalyzed homoenolate formation has been developed. Interestingly, the reaction led to bicyclic delta-lactones instead of the expected gamma-spirolactones, presumably by the uncommon [8 + 3] annulation pathway. The strategy works well with a variety of enals. 相似文献
80.
[reaction: see text] A very efficient method for the simultaneous protection of the amino group and activation of the carboxyl group of amino acids is reported using propargyl pentafluorophenyl carbonate (PocOPfp). The amino group is protected as a propargyloxycarbonyl (Poc) derivative, and the carboxyl group is activated as a pentafluorophenyl ester. The yields obtained are good to excellent ranging from 60 to 87%. 相似文献