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排序方式: 共有225条查询结果,搜索用时 15 毫秒
1.
The behavior and suitability of cold-formed lipped angle members for X-bracing with redundant have been studied. For the purpose, two full-scale panel tests were carried out. The first panel was designed so that the compression member would fail by buckling in flexural mode and the second panel in flexural-torsional mode. The members were designed using ASCE Manual No. 52. Theoretical aspects of least radius of gyration and buckling behavior of this bracing system have been discussed. The investigation on first panel, revealed that the member would buckle only in the flexural-torsional mode although flexural buckling would govern the design. The second panel test result showed that, the buckling mode and strength of the system for lipped angle sections can be predicted reasonably well. 相似文献
2.
E. Sriram Prasath Sreraman Muralidharan Chiranjib Mitra Prasanta K. Panigrahi 《Quantum Information Processing》2012,11(2):397-410
We investigate the entanglement properties of the two magnon states and explicate conditions under which, the two magnon state
becomes useful for several quantum communication protocols. We systematically study the temporal behaviour of concurrence
to find out the effect of exchange interaction on entanglement. The two magnon state, which is potentially realizable in quantum
dots using Heisenberg exchange interaction, is found to be suitable for carrying out deterministic teleportation of an arbitrary
two qubit composite system. Further, conditions for which the channel capacity reaches “Holevo bound”, allowing four classical
bits to be transmitted through two qubits are derived. Later, an unconventional protocol is given to demonstrate that this
state can be used for sharing of a two qubit entangled state among two parties. 相似文献
3.
I. Prakash P. Muralidharan N. Nallamuthu N. Satyanarayana M. Venkateswarlu David Carnahan 《Journal of the American Ceramic Society》2006,89(7):2220-2225
NiAl2 O4 /SiO2 and Co2+ -doped NiAl2 O4 /SiO2 nanocomposite materials of compositions 5% NiO – 6% Al2 O3 – 89% SiO2 and 0.2% CoO – 4.8% NiO – 6% Al2 O3 – 89% SiO2 , respectively, were prepared by a sol–gel process. NiAl2 O4 and cobalt-doped NiAl2 O4 nanocrystals were grown in a SiO2 amorphous matrix at around 1073 K by heating the dried gels from 333 to 1173 K at the rate of 1 K/min. The formations of NiAl2 O4 and cobalt-doped NiAl2 O4 nanocrystals in SiO2 amorphous matrix were confirmed through X-ray powder diffraction, Fourier transform infrared spectroscopy, differential scanning calorimeter, transmission electron microscopy (TEM), and optical absorption spectroscopy techniques. The TEM images revealed the uniform distribution of NiAl2 O4 and cobalt-doped NiAl2 O4 nanocrystals in the amorphous SiO2 matrix and the size was found to be ∼5–8 nm. 相似文献
4.
George Ting-Kuo Fey P. Muralidharan Cheng-Zhang Lu Yung-Da Cho 《Electrochimica acta》2006,51(23):4850-4858
An enhanced electrochemical performance LiCoO2 cathode was synthesized by coating with various wt.% of La2O3 to the LiCoO2 particle surfaces by a polymeric method, followed by calcination at 923 K for 4 h in air. The surface-coated materials were characterized by XRD, TGA, SEM, TEM, BET and XPS/ESCA techniques. XRD patterns of La2O3-coated LiCoO2 revealed that the coating did not affect the crystal structure, α-NaFeO2, of the cathode material compared to pristine LiCoO2. TEM images showed a compact coating layer on the surface of the core material that had an average thickness of about ∼15 nm. XPS data illustrated that the presence of two different environmental O 1s ions corresponds to the surface-coated La2O3 and core material. The electrochemical performance of the coated materials by galvanostatic cycling studies suggest that 2.0 wt.% coated La2O3 on LiCoO2 improved cycle stability (284 cycles) by a factor of ∼7 times over the pristine LiCoO2 cathode material and also demonstrated excellent cell cycle stability when charged at high voltages (4.4, 4.5 and 4.6 V). Impedance spectroscopy demonstrated that the enhanced performance of the coated materials is attributed to slower impedance growth during the charge-discharge processes. The DSC curve revealed that the exothermic peak corresponding to the release of oxygen at ∼464 K was significantly smaller for the La2O3-coated cathode material and recognized its high thermal stability. 相似文献
5.
Aishani Mazumder Chung Kim Nguyen Thiha Aung Mei Xian Low Md. Ataur Rahman Salvy P. Russo Sherif Abdulkader Tawfik Shifan Wang James Bullock Vaishnavi Krishnamurthi Nitu Syed Abhishek Ranjan Ali Zavabeti Irfan H. Abidi Xiangyang Guo Yongxiang Li Taimur Ahmed Torben Daeneke Akram Al-Hourani Sivacarendran Balendhran Sumeet Walia 《Advanced functional materials》2023,33(36):2303641
Miniaturization and energy consumption by computational systems remain major challenges to address. Optoelectronics based synaptic and light sensing provide an exciting platform for neuromorphic processing and vision applications offering several advantages. It is highly desirable to achieve single-element image sensors that allow reception of information and execution of in-memory computing processes while maintaining memory for much longer durations without the need for frequent electrical or optical rehearsals. In this work, ultra-thin (<3 nm) doped indium oxide (In2O3) layers are engineered to demonstrate a monolithic two-terminal ultraviolet (UV) sensing and processing system with long optical state retention operating at 50 mV. This endows features of several conductance states within the persistent photocurrent window that are harnessed to show learning capabilities and significantly reduce the number of rehearsals. The atomically thin sheets are implemented as a focal plane array (FPA) for UV spectrum based proof-of-concept vision system capable of pattern recognition and memorization required for imaging and detection applications. This integrated light sensing and memory system is deployed to illustrate capabilities for real-time, in-sensor memorization, and recognition tasks. This study provides an important template to engineer miniaturized and low operating voltage neuromorphic platforms across the light spectrum based on application demand. 相似文献
6.
7.
8.
This paper describes the preparations and lithium-ion conductivities of various solid polymer electrolytes for potential use in high-energy density lithium-ion batteries. The ring opening polymerization of epoxides (M1–M6), catalyzed by Zn(II), Cu(II) and Cd(II) complexes in the presence of tetrabutylammonium bromide (TBAB), yielded polyethers (P1–P6) in which phosphates were attached as pendant groups. A reaction condition where Zn(II) catalyst used slightly excess to TBAB increased the polymerization rate remarkably and yielded the polyethers with higher molar masses in a short time. These polymerizations proceeded following a “monomer activated anionic ring opening polymerization” mechanism. These living like polymerizations also progressed according to “formation of polymer chain per initiator” model. The solid-state lithium-ion conductivities of these polymers were examined using lithium bis(trifluoromethanesulfonyl)imide (LiTFSI). The conductivity of one of the solid polymer electrolytes with 40 wt% of LiTFSI was 5.2 × 10−5 S cm−1 at room temperature and 2.9 × 10−4 S cm−1 at 80 °C. 相似文献
9.
Govindarajan Muralidharan Kanth Kurumaddali Andrew K. Kercher Larry Walker Scott G. Leslie 《Journal of Electronic Materials》2013,42(2):240-248
There is a need for next-generation, high-performance power electronic packages and systems utilizing wide-band-gap devices to operate at high temperatures in automotive and electricity transmission applications. Sn-3.5Ag solder is a candidate for use in such packages with potential maximum operating temperatures of about 200°C. However, there is a need to understand the thermal cycling reliability of Sn-3.5Ag solders subject to such high-temperature operating conditions. The results of a study on the damage evolution occurring in large-area Sn-3.5Ag solder joints between silicon dies and direct bonded copper substrates with Au/Ni-P metallization subject to thermal cycling between 200°C and 5°C are presented in this paper. Interface structure evolution and damage accumulation were followed using high-resolution X-ray radiography, cross-sectional optical and scanning electron microscopies, and X-ray microanalysis in these joints for up to 3000 thermal cycles. Optical and scanning electron microscopy results showed that the stresses introduced by the thermal cycling result in cracking and delamination at the copper–intermetallic compound interface. X-ray microanalysis showed that stresses due to thermal cycling resulted in physical cracking and breakdown of the Ni-P barrier layer, facilitating Cu-Sn interdiffusion. This interdiffusion resulted in the formation of Cu-Sn intermetallic compounds underneath the Ni-P layer, subsequently leading to delamination between the Ni-rich layer and Cu-Sn intermetallic compounds. 相似文献
10.
Stevenson KA Muralidharan G Maya L Wells JC Barhen J Thundat T 《Journal of nanoscience and nanotechnology》2002,2(3-4):397-404
Functionalized gold nanoparticles have been covalently bound to internal, modified sites on double-stranded DNA. Gold nanoparticles coated with mercaptosuccinic acid or thioctic acid were bound to amino-modified thymine bases on double-stranded DNA. Visible absorption spectra, gel electrophoresis, and atomic force microscopy were used to analyze the products. Thiol groups were added to one end of the gold/nanoparticle product, which was then attached to a gold surface. This method has the potential to allow controlled placement of particles with subnanometer precision and to allow attachment of the product to fixed contacts for nanodevice fabrication. 相似文献