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91.
Electron impact collision strengths, energy levels, oscillator strengths, and spontaneous radiative decay rates are calculated for Mg VI. The configurations used are 2s22p3, 2s2p4, 2p5, 2s22p23s, 2s22p23p, and 2s22p23d, giving rise to 72 fine-structure levels in intermediate coupling. Collision strengths are calculated at five incident energies, 12, 24, 36, 48, and 60 Ry. Excitation rate coefficients are calculated as a function of electron temperature by assuming a Maxwellian electron velocity distribution. Using the excitation rate coefficients and the radiative transition rates, statistical equilibrium equations for level populations are solved at electron densities covering the range of 108-1014 cm−3 at an electron temperature of log Te (K) = 5.6, corresponding to maximum abundance of Mg VI. Relative and absolute spectral line intensities are calculated and compared with observations of a solar active region. 相似文献
92.
A.K. Bhatia 《Atomic Data and Nuclear Data Tables》2007,93(2):275-353
Electron impact collision strengths, energy levels, oscillator strengths and spontaneous radiative decay rates are calculated for Si XI. The configurations used are 2s2, 2s2p, 2p2, 2l3l′, 2l4l′ and 2s5l′, with l = s,p and l′ = s,p,d giving rise to 92 fine-structure levels in intermediate coupling. Collision strengths are calculated at five incident energies (35, 70, 105, 140, and 175 Ry) in the distorted wave approximation. Excitation rate coefficients are calculated as a function of electron temperature by assuming a Maxwellian electron velocity distribution. Using the excitation rate coefficients and the radiative transition rates of the present work, and R-Matrix results for the 2s2, 2s2p, 2p2 configurations available in the literature, statistical equilibrium equations for level populations are solved at electron densities covering the range of 108-1014 cm−3 at an electron temperature of log Te(K) = 6.2, corresponding to the maximum abundance of Si XI. Spectral line intensities are calculated, and their diagnostic relevance is discussed. This dataset will be made available in the next version of the CHIANTI database. 相似文献
93.
Most commonly used river water quality models for biochemical oxygen demand (BOD) and dissolved oxygen (DO) simulations are mainly based on advection, decay, settling, and loading functions. Using these concepts, refined river water quality models for BOD and DO simulations are developed in the present work considering a large number of physically based parameters and input variables. The refined models developed can be transformed to some of the commonly used river water quality models, if physically based parameters and input variables are omitted or removed. To test the applicability of the refined models developed and commonly used models, a total of 732 water quality and flow data sets are collected during March 1999–February 2000 from 22 sampling stations of the River Kali in India. River Kali is a highly polluted river in India and receives continuous inflow of untreated point source pollution from municipal and industrial wastes and nonpoint source pollution from agricultural areas. Newton–Raphson technique is used to optimize the model parameters during calibration and the performance of different models are evaluated using error estimation, viz. standard error and mean multiplicative error, and correlation statistics (r2). The results indicate that the BOD–DO models proposed by Camp in 1963 provide better results in comparison to other commonly used models. Moreover, the refined models developed for BOD and DO simulations minimize error estimates and improve correlation between observed and computed BOD and DO values of River Kali. 相似文献
94.
Nanda Gopal Sahoo Yong Chae Jung Jae Whan Cho 《Materials and Manufacturing Processes》2007,22(4):419-423
We report the electroactive shape memory composites obtained by shape memory polyurethane block copolymer (PU) and multi-walled carbon nanotubes (MWNTs), and polypyrrole (PPy). An addition of combined MWNTs and PPy contributed to an enhancement in conductivity of PU-MWNTs composites. PU containing 2.5% MWNTs showed better mechanical and thermal properties than other composites, but conductivity was not sufficient for showing the shape memory effect by applying electrical voltages. However, when the composite was lightly coated by PPy (2.5%), its conductivity was the highest than other composites. Such the conductivity of this composite was enough to show electroactive shape recovery by heating above transition temperature of 40-48°C due to melting of polycaprolactone soft segment domain. The good shape recovery of 90-96% could be obtained in the shape recovery test when an electric field of 25 V was applied. 相似文献
95.
A.Z. Abdullah A.H. Kamaruddin N. Razali H. Abdullah S. Bhatia 《Science and Technology of Advanced Materials》2007,8(4):249-256
A series of mesoporous silicas (MS-1-MS-9) were synthesized at different gel compositions using a triblock copolymer (TCP), poly(ethylene oxide)-poly(propylene oxide)-poly(ethylene oxide), as the surfactant. The interactive effects of acidity, the contents of tetraethyl orthosilicate (TEOS) and the surfactant, and the gelling temperature on the characteristics of the final material were simultaneously characterized. Increasing acidity favored mesopore formation. A material with a surface area of 760 m2/g, mostly in the mesoporous range, was obtained at 1.0(TEOS):0.017(TCP):7.3HCl:115.7H2O. Mesopore formation was predominantly determined by the TEOS:TCP ratio and was promoted with its increase from 1.56:1 to 2.09:1. A further increase to 2.61:1 was detrimental. Whereas increasing the TCP content to 3.5% w/w improved micellization, a further increase to 4.6% should be avoided. Mesoporous silicas showed low crystallinity but a high degree of hexagonal mesoscopic organization. The weak surface acidity was attributed to surface silanols, the number of which was proportional to mesoporosity. 相似文献
96.
Swapan K. Bhattacharya Mahesh G. Varadarajan Premjeet Chahal Gopal C. Jha Rao R. Tummala 《Journal of Electronic Materials》2007,36(3):242-244
To realize embedded resistors on multilayer benzocyclobutene (BCB) either on-chip or on-board, a low-cost large format electroless
process for deposition of NiP and NiWP thin-film resistors using both low-temperature (25°C) and high-temperature (90°C) baths
has been developed. The electroless process exhibits uniform resistor thickness in the submicron range and offers low profile
and excellent adhesion to the BCB dielectric layer. The resistor films also act as a seed layer for direct electroplating
of copper traces. The NiP alloys can also be tailored to a variable temperature coefficient of resistance (TCR) with different
alloy compositions. The electroless process can be adopted in the PCB manufacturing industries with no additional investment.
This article is the first report on electroless plated thin film resistors on low loss BCB dielectric. 相似文献
97.
Thermoluminescence (TL) characteristics of NaYF4 crystals doped with Sm3+ have been studied after γ-ray irradiation. Dependence of luminescence efficiency on Sm3+ concentration and radiation dose has been measured and possible applications of NaYF4: Sm3+ as a novel phosphor for TL dosimetry have been investigated. The efficiency of 0·3 mole% Sm3+ doped NaYF4 crystal has been found to be maximum and comparable with commercial thermoluminescence dosimetric (TLD) materials. 相似文献
98.
Judy Gopal Manikandan Muthu Se-Chul Chun Hui-Fen Wu 《Proteomics. Clinical applications》2015,9(5-6):469-481
Urine proteomics has become a subject of interest, since it has led to a number of breakthroughs in disease diagnostics. Urine contains information not only from the kidney and the urinary tract but also from other organs, thus urinary proteome analysis allows for identification of biomarkers for both urogenital and systemic diseases. The following review gives a brief overview of the analytical techniques that have been in practice for urinary proteomics. MALDI-MS technique and its current application status in this area of clinical research have been discussed. The review comments on the challenges facing the conventional MALDI-MS technique and the upgradation of this technique with the introduction of nanotechnology. This review projects nano-based techniques such as nano-MALDI-MS, surface-assisted laser desorption/ionization, and nanostructure-initiator MS as the platforms that have the potential in trafficking MALDI-MS from the lab to the bedside. 相似文献
99.
An understanding of human factors and ergonomics facilitates the design of artefacts, tasks and environments that fulfil their users’ physical and cognitive requirements. Research in these fields furthers the goal of efficiently accommodating the desired percentage of user populations through enhanced awareness and modelling of human variability. Design for sustainability (DfS) allows for these concepts to be leveraged in the broader context of designing to minimise negative impacts on the environment. This paper focuses on anthropometry and proposes three ways in which its consideration is relevant to DfS: reducing raw material consumption, increasing usage lifetimes and ethical human resource considerations. This is demonstrated through the application of anthropometry synthesis, virtual fitting, and sizing and adjustability allocation methods in the design of an industrial workstation seat for use in five distinct global populations. This work highlights the importance of and opportunities for using ergonomic design principles in DfS efforts. Practitioner Summary: This research demonstrates the relevance of some anthropometry-based ergonomics concepts to the field of design for sustainability. A global design case study leverages human variability considerations in furthering three sustainable design goals: reducing raw material consumption, increasing usage lifetimes and incorporating ethical human resource considerations in design. 相似文献
100.
Baldridge K.K. Greenberg J.P. Sudholt W. Mock S. Altintas I. Amoreira C. Potier Y. Birnbaum A. Bhatia K. Taufer M. 《Proceedings of the IEEE. Institute of Electrical and Electronics Engineers》2005,93(3):510-521
Evolving technologies, as exemplified by computational grids and Web services, have made it possible to solve new scientific problems that would not have been feasible previously. In order to make such advances available to the community in general and to be able to solve new problems, not necessarily from the same discipline, it is imperative to build tools that provide a common user interface in order that application programmers and users do not have to be concerned with particulars of Web services and their underlying code, computational platforms, or with data file formats. We will describe our efforts in creating a computational chemistry environment that encompasses a general scientific workflow environment, a domain specific example for quantum chemistry, our ongoing design of a workflow user interface, and our efforts at database integration. 相似文献