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排序方式: 共有237条查询结果,搜索用时 15 毫秒
61.
K. V. Nagalakshmi M. Padma P. Shyamala V. Srikanth A. Satyanarayana P. V. SubbaRao 《Transition Metal Chemistry》2013,38(5):523-527
The kinetics of dissociation of bis(2,4,6–tripyridyl-s-triazine) iron(II), ([Fe(TPTZ)2]2+) has been studied in CTAB/chloroform/hexane reverse micellar medium. In the absence of acid, the reaction is immeasurably slow and does not go to completion in conventional aqueous medium but is markedly accelerated and takes place with a rate constant equal to 55.3 × 10?3 s?1 and goes to completion in reverse micelles. The significant increase in rate is attributed to the special properties of the water pool in the reverse micelles like low dielectric constant, nucleophilic effect of Br- ion, and favorable partitioning of TPTZ in the organic phase. The rate of the reaction decreases with increase in W (=[H2O]/[CTAB]) at constant CTAB concentration and remains constant with increase in CTAB at fixed W. The results are compared with other closely related systems. 相似文献
62.
Luv Verma Jefferson Andrew Srinivasan M. Sivakumar Gurusamy Balaganesan Srikanth Vedantam Hom N. Dhakal 《Molecules (Basel, Switzerland)》2021,26(1)
This paper aims to estimate the enhancement in the energy absorption characteristics of the glass fiber reinforced composites (GFRP) by embedding prestrained pseudo-elastic shape memory alloy (SMA) that was used as a secondary reinforcement. The pseudo-elastic SMA (PE-SMA) embedded were in the form of wires and have an equiatomic composition (i.e., 50%–50%) of nickel (Ni) and titanium (Ti). These specimens are fabricated using a vacuum-assisted resin infusion process. The estimation is done for the GFRP and SMA/GFRP specimens at four different impact velocities (65, 75, 85, and 103 m/s) using a gas-gun impact set-up. At all different impact velocities, the failure modes change as we switch from GFRP to SMA/GFRP specimen. In the SMA/GFRP specimen, the failure mode changed from delamination in the primary region to SMA-pull out and SMA deformation. This leads to an increase in the ballistic limit. It is observed that energy absorbed by SMA/GFRP specimens is higher than the GFRP specimens subjected to the same levels of impact energy. To understand the damping capabilities of SMA embedment, vibration signals are captured, and the damping ratio is calculated. SMA dampens the vibrations imparted by the projectile to the specimen. The damping ratio of the SMA/GFRP specimens is higher than the GFRP specimens. The damping effect is more prominent below the ballistic limit when the projectile got rebounded (65 m/s). 相似文献
63.
H. Srikanth A.K. Raychaudhuri C.R. Venkateswara Rao P. Ramasamy Hemantkumar N. Aiyer C.N.R. Rao 《Physica C: Superconductivity and its Applications》1992,200(3-4):372-376
Tunneling studies have been carried out on single crystals of Bi2Ca1−xSrxCu2O8+δ over a wide range of compositions wherein the hole concentration varies by a factor of 2.5. The 2Δ value varies between 25 meV and 75 meV over the composition range studied, but scales with 2Δ/kBTc≈9.5 throughout. 相似文献
64.
65.
A protocol based on quantum error correction based characterization of quantum dynamics (QECCD) is developed for quantum process tomography on a two-qubit system interacting dissipatively with a vacuum bath. The method uses a 5-qubit quantum error correcting code that corrects arbitrary errors on the first two qubits, and also saturates the quantum Hamming bound. The dissipative interaction with a vacuum bath allows for both correlated and independent noise on the two-qubit system. We study the dependence of the degree of the correlation of the noise on evolution time and inter-qubit separation. 相似文献
66.
Singamaneni S Chang S Jang JH Davis W Thomas EL Tsukruk VV 《Physical chemistry chemical physics : PCCP》2008,10(28):4093-4105
We demonstrate that organized, porous, polymer microstructures with continuous open nanoscale pores and a sub-micron spacing obtained via interference lithography can be successfully utilized in a non-traditional field of ordered polymer microcomposites. The examples presented here include porous matrices for the fabrication of binary, glassy-rubbery microcomposites with intriguing mechanical properties with large energy dissipation and lattice-controlled fracturing. 相似文献
67.
Dr. Gourishetty Srikanth Dr. Anil Ravi Dr. Anusha Sebastian Jobi Joseph Prof. Monther A. Khanfar Prof. Mohammed I. El-Gamal Prof. Raed A. Al-Qawasmeh Prof. Ihsan A. Shehadi Scott McN. Sieburth Prof. Imad A. Abu-Yousef Prof. Amin F. Majdalawieh Prof. Taleb H. Al-Tel 《European journal of organic chemistry》2023,26(13):e202300080
The discovery of novel small molecules endowed with high 3D-content remains a powerful tool for interrogating underrepresented biological space. To this end, the pseudo-natural products (pseudo-NP) strategy has become one of the most important tools to deliver biologically significant chemical probes. In this article, we describe the development of a new class of pseudo-NP collection, through connecting tryptamines with a furanose derivative followed by subjecting the product from this operation to a ring distortion strategy that led to diastereoselective synthesis of camptothecin-like compounds. This process is driven by a cascade that unites Pictet–Spengler reaction with Michael addition reaction, followed by oxidative-ring enlargement and subsequent transannular aldol cyclization delivering camptothecin-like architectures. The obtained diastereoselectivity was verified using density functional theory (DFT) calculations. 相似文献
68.
Effect of three-phase contact line topology on dynamic contact angles on heterogeneous surfaces 总被引:1,自引:0,他引:1
Anantharaju N Panchagnula MV Vedantam S Neti S Tatic-Lucic S 《Langmuir : the ACS journal of surfaces and colloids》2007,23(23):11673-11676
Cassie-Baxter theory has traditionally been used to study liquid drops in contact with microstructured surfaces. The Cassie-Baxter theory arises from a minimization of the global Gibbs free energy of the system but does not account for the topology of the three-phase contact line. We experimentally compare two situations differing only in the microstructure of the roughness, which causes differences in contact line topology. We report that the contact angle is independent of area void fraction for surfaces with microcavities, which correspond to situations when the advancing contact line is continuous. This result is in contrast with Cassie-Baxter theory, which uses area void fraction as the determining parameter, regardless of the type of roughness. 相似文献
69.
The thermodynamics and kinetics of a many-body system can be described in terms of a potential energy landscape in multidimensional configuration space. The partition function of such a landscape can be written in terms of a density of states, which can be computed using a variety of Monte Carlo techniques. In this paper, a new self-consistent Monte Carlo method for computing density of states is described that uses importance sampling and a multiplicative update factor to achieve rapid convergence. The technique is then applied to compute the equilibrium quench probability of the various inherent structures (minima) in the landscape. The quench probability depends on both the potential energy of the inherent structure and the volume of its corresponding basin in configuration space. Finally, the methodology is extended to the isothermal-isobaric ensemble in order to compute inherent structure quench probabilities in an enthalpy landscape. 相似文献
70.
Srikanth Sangam Raut Sushil Dubey Satish Kumar Ishii Idaku Javed Arshad Goel Sanket 《The European physical journal. E, Soft matter》2021,44(8):1-19
The European Physical Journal E - Interaction of cytoskeletal filaments, motor proteins, and crosslinking proteins drives important cellular processes such as cell division and cell movement.... 相似文献