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排序方式: 共有518条查询结果,搜索用时 15 毫秒
501.
Heestand GM Haynam CA Wegner PJ Bowers MW Dixit SN Erbert GV Henesian MA Hermann MR Jancaitis KS Knittel K Kohut T Lindl JD Manes KR Marshall CD Mehta NC Menapace J Moses E Murray JR Nostrand MC Orth CD Patterson R Sacks RA Saunders R Shaw MJ Spaeth M Sutton SB Williams WH Widmayer CC White RK Whitman PK Yang ST Van Wonterghem BM 《Applied optics》2008,47(19):3494-3499
A single beamline of the National Ignition Facility (NIF) has been operated at a wavelength of 526.5 nm (2 omega) by frequency converting the fundamental 1053 nm (1 omega) wavelength with an 18.2 mm thick type-I potassium dihydrogen phosphate (KDP) second-harmonic generator (SHG) crystal. Second-harmonic energies of up to 17.9 kJ were measured at the final optics focal plane with a conversion efficiency of 82%. For a similarly configured 192-beam NIF, this scales to a total 2 omega energy of 3.4 MJ full NIF equivalent (FNE). 相似文献
502.
P. C. Collins C. V. Haden I. Ghamarian B. J. Hayes T. Ales G. Penso V. Dixit G. Harlow 《JOM Journal of the Minerals, Metals and Materials Society》2014,66(7):1299-1309
Electron beam direct manufacturing, synonymously known as electron beam additive manufacturing, along with other additive “3-D printing” manufacturing processes, are receiving widespread attention as a means of producing net-shape (or near-net-shape) components, owing to potential manufacturing benefits. Yet, materials scientists know that differences in manufacturing processes often significantly influence the microstructure of even widely accepted materials and, thus, impact the properties and performance of a material in service. It is important to accelerate the understanding of the processing–structure–property relationship of materials being produced via these novel approaches in a framework that considers the performance in a statistically rigorous way. This article describes the development of a process model, the assessment of key microstructural features to be incorporated into a microstructure simulation model, a novel approach to extract a constitutive equation to predict tensile properties in Ti-6Al-4V (Ti-64), and a probabilistic approach to measure the fidelity of the property model against real data. This integrated approach will provide designers a tool to vary process parameters and understand the influence on performance, enabling design and optimization for these highly visible manufacturing approaches. 相似文献
503.
K. Eswar Prasad B. Li N. Dixit M. Shaffer S. N. Mathaudhu K. T. Ramesh 《JOM Journal of the Minerals, Metals and Materials Society》2014,66(2):291-304
We review the dynamic behavior of magnesium alloys through a survey of the literature and a comparison with our own high-strain-rate experiments. We describe high-strain-rate experiments (at typical strain rates of 103 s?1) on polycrystalline pure magnesium as well as two magnesium alloys, AZ31B and ZK60. Both deformation and failure are considered. The observed behaviors are discussed in terms of the fundamental deformation and failure mechanisms in magnesium, considering the effects of grain size, strain rate, and crystallographic texture. A comparison of current results with the literature studies on these and other Mg alloys reveals that the crystallographic texture, grain size, and alloying elements continue to have a profound influence on the high-strain-rate deformation behavior. The available data set suggests that those materials loaded so as to initiate extension twinning have relatively rate-insensitive strengths up to strain rates of several thousand per second. In contrast, some rate dependence of the flow stress is observed for loading orientations in which the plastic flow is dominated by dislocation mechanisms. 相似文献
504.
Ashish Bhatnagar Sunita K. Pandey Viney Dixit Vivek Shukla Rohit R. Shahi M.A. Shaz O.N. Srivastava 《International Journal of Hydrogen Energy》2014
The present investigation describes the hydrogen storage properties of 2:1 molar ratio of MgH2–NaAlH4 composite. De/rehydrogenation study reveals that MgH2–NaAlH4 composite offers beneficial hydrogen storage characteristics as compared to pristine NaAlH4 and MgH2. To investigate the effect of carbon nanostructures (CNS) on the de/rehydrogenation behavior of MgH2–NaAlH4 composite, we have employed 2 wt.% CNS namely, single wall carbon nanotubes (SWCNT) and graphene nano sheets (GNS). It is found that the hydrogen storage behavior of composite gets improved by the addition of 2 wt.% CNS. In particular, catalytic effect of GNS + SWCNT improves the hydrogen storage behavior and cyclability of the composite. De/rehydrogenation experiments performed up to six cycles show loss of 1.50 wt.% and 0.84 wt.% hydrogen capacity in MgH2–NaAlH4 catalyzed with 2 wt.% SWCNT and 2 wt.% GNS respectively. On the other hand, the loss of hydrogen capacity after six rehydrogenation cycles in GNS + SWCNT (1.5 + 0.5) wt.% catalyzed MgH2–NaAlH4 is diminished to 0.45 wt.%. 相似文献
505.
The solvent extracted vegetable seed oils of Cucurbitaceae family viz. Bitter gourd (Momordica charentia), Small bitter gourd (Momordica dioica), Bottle gourd (Lagenaria siscraria) and Ridge gourd (Luffa acutangula) were evaluated as grain protectant against callosobruchus chinensis on the stored legume-pulse grains. All the vegetable seed oils were found effective as legume-pulse grain protectant, which provided, negligible weight loss at the oil-application rate of 6-8 mL/kg in legume-pulse grain after 60 days storage at laboratory conditions. The milling yield and degree of dehusking gets improved after the oil application. The use of solvent extracted Small bitter gourd seed oil at the level of 6-8 mL/kg of legume-pulse grain sample resulted in the improved apparent degree of dehusking from 40.0 to 72.59, 59.88 to 92.44, 63.39 to 87.50 and 57.0 to 79.43 for Pigeonpea (Canjanus cajan), Chickpea (Cicer arietinum), Urdbean (Phaseolus mungo) and Mungbean (Phaseolus radiatus), respectively. 相似文献
506.
Amandeep Kaur Alok Sharma Madhu Sameer Dixit Kashmir Singh Santosh Kumar Upadhyay 《International journal of molecular sciences》2022,23(23)
The hyperosmolality-gated calcium-permeable channels (OSCA) are pore-forming transmembrane proteins that function as osmosensors during various plant developmental processes and stress responses. In our analysis, through in silico approaches, a total of 42 OSCA genes are identified in the Triticum aestivum genome. A phylogenetic analysis reveals the close clustering of the OSCA proteins of Arabidopsis thaliana, Oryza sativa, and T. aestivum in all the clades, suggesting their origin before the divergence of dicots and monocots. Furthermore, evolutionary analyses suggest the role of segmental and tandem duplication events (Des) and purifying selection pressure in the expansion of the OSCA gene family in T. aestivum. Expression profiling in various tissue developmental stages and under abiotic and biotic stress treatments reveals the probable functioning of OSCA genes in plant development and the stress response in T. aestivum. In addition, protein–protein and protein–chemical interactions reveal that OSCA proteins might play a putative role in Ca2+-mediated developmental processes and adaptive responses. The miRNA interaction analysis strengthens the evidence for their functioning in various biological processes and stress-induced signaling cascades. The current study could provide a foundation for the functional characterization of TaOSCA genes in future studies. 相似文献
507.
Raghwendra K. Singh Nagendra Kumar Dharmendra Dixit 《International Journal of Communication Systems》2023,36(15):e5564
We study the energy harvesting (EH)-assisted system model based on the performance of a dual-hop cooperative communication system that is subjected to Nakagami- fading. Through the partial relay selection method, the selection of th best relay (BR) is performed among amplify and forward (AF) relays, which can harvest energy from radio frequency signals. At the receiver, the selection combining scheme is considered to select between the signals of th best relaying path and the direct path. For this considered system, we compute the closed-form expressions of outage probability (OP) and the average symbol error rate (ASER) for higher order quadrature amplitude modulation (QAM) techniques, especially for rectangular QAM, cross QAM, and hexagonal QAM. Further, a new moment-generating function expression is obtained which is used to derive the ASER expression related to the generalized non-coherent modulation technique. We also give the asymptotic expression of OP to find out the diversity order. Furthermore, we study the effect of fading parameters, th BR, and other factors on system behavior. Finally, we verify the derived expressions with Monte Carlo simulations. 相似文献
508.
Aditi Dixit Dr. Jeet Kalia 《Chembiochem : a European journal of chemical biology》2023,24(13):e202200755
Metabolites orchestrate cellular processes as either substrates, co-enzymes, inhibitors, or activators of cellular proteins such as enzymes and receptors. Although traditional biochemical and structural biology-based approaches have been successfully employed for the discovery of protein-metabolite interactions, they often fail to detect transient and low-affinity biomolecular relationships. Another limitation of these approaches is that they are performed under in vitro conditions lacking the physiological context. Recently developed mass spectrometry-based methodologies overcome both these shortcomings, and have resulted in the discovery of global protein-metabolite cellular interaction networks. Herein, we describe traditional and modern approaches for the discovery of protein-metabolite interactions, and discuss the impact of these discoveries on our understanding of cellular physiology and on drug development. 相似文献
509.
Biswajit Samir De Ram Ji Dixit Abhas Anand Vicky Rahul Dhongde Suddhasatwa Basu 《加拿大化工杂志》2023,101(6):3167-3179
Electrochemical conversion of biomass to value-added chemicals has gained impetus in recent years. Herein, we present a methodology for recovering biomass-derived 2-furoic acid from the dilute aqueous stream by reactive extraction. The reactive extraction was performed using a chemical extractant, trioctylamine (TOA), with diluents (octanol, chloroform, and diethyl ether). Equilibrium parameters influencing the recovery of 2-furoic acid were evaluated. Using TOA in various diluents, the 2-furoic acid was recovered with 85%–99% efficiency. A 1:1 complex of the 2-furoic acid—TOA was formed in the organic phase, and the experimental equilibrium complexation constant was compared with that obtained from the relative basicity and Langmuir models. The equilibrium parameters were used for column design to estimate the solvent to feed ratio (S/F) and the number of theoretical stages (NTS). The NTS required is 12 to attain 99% recovery of 2-furoic acid in counter-current extraction. The present study sheds light on the reactive extraction process adopted for process intensification with electrochemical conversion, paving the way for the commercialization of valuable products obtained from biomass. 相似文献
510.