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111.
Chronic ischemia may cause end stage renal disease, especially in older patients with atherosclerotic renal artery stenosis. Examining the pathology of the ischemic kidney is a fundamental first step toward understanding the mechanisms of this injury. In experimental renal hypoperfusion, there is evidence of a mixture of adaptive responses, tubular and endothelial cell damage and repair events. These processes are reflected in a wide spectrum of morphological changes that include atrophy, focal necrosis, epithelial regeneration, apoptosis, inflammation, interstitial fibrosis, and thrombosis. The most severe damage is seen in the outer medulla, a region with marginal oxygenation even in normal circumstances. In the usual clinical case, the effects of aging, pre-existent hypertension, and the process of atherosclerosis further complicate the pathological picture. Lesions related to these factors include arteriosclerosis, athero-emboli, various types of glomerulosclerosis, and severe tubulointerstitial damage leading to "atubular glomeruli" and regional cortical scarring (nephrosclerosis). In this article, some mechanisms determining the varied and complex pathological findings that may be observed in individual cases are outlined. 相似文献
112.
KL Edwards B Newman E Mayer JV Selby RM Krauss MA Austin 《Canadian Metallurgical Quarterly》1997,14(3):241-253
The insulin resistance syndrome (IRS) is characterized by a combination of interrelated coronary heart disease (CHD) risk factors, including low high-density lipoprotein cholesterol (HDL-C) levels, obesity and increases in triglyceride (TG), blood pressure, small low-density lipoprotein particles (LDL), and both fasting and postload plasma insulin and glucose. Using factor analysis, we previously identified 3 uncorrelated factors that explained 66% of the variance among these variables, based on data from women participating in examination 2 of the Kaiser Permanente Women Twins Study in Oakland, CA during 1989-1990. The factors were interpreted as: 1) body mass/fat distribution, 2) insulin/glucose, and 3) lipids: TG, HDL-C, LDL peak particle diameter. In this analysis, heritability of each of the factors was estimated based on data from 140 monozygotic and 96 dizygotic pairs of non-diabetic women twins. Heritability estimates were calculated using the classical approach, the analysis of variance (ANOVA) approach, and the maximum likelihood approach. For the body mass/fat distribution factor heritability estimates suggest moderate genetic influences; 0.61 (P < 0.001), 0.14 (P > 0.05), and 0.71 (P < 0.001), respectively. The insulin/glucose factor appeared to be highly heritable, with estimates of 0.87, 0.92, and 0.57 (all P < 0.001), respectively. The heritability estimates for the lipid factor were moderate and consistent across methods: 0.25 (P < 0.10), 0.32 (P < 0.05), and 0.30 (P < 0.05), respectively. These results are consistent with genetic influences on each of the 3 "factors," and suggest that both genetic and environmental effects are involved in the clustering of IRS risk factors. 相似文献
113.
114.
Antonio Fabozzi Rosa Vitiello Irene Russo Krauss Mauro Iuliano Gaetano De Tommaso Angela Amoresano Gabriella Pinto Luigi Paduano Christopher Jones Martino Di Serio Gerardino D'Errico 《Journal of surfactants and detergents》2019,22(1):115-124
Amine-oxide surfactants have emerged as highly stable, nontoxic, and cost-effective constituents of detergent formulations, specifically as wetting agents and foam boosters. With the aim of enhancing their functional behavior, a new member of this family, N,N-dimethyl-2-propylheptan-1-amine oxide, bearing a branched alkyl tail (C10DAO-branched) was synthesized and purified using a simple and easily scalable strategy starting from 2-propylheptan-1-ol. 2D-nuclear magnetic resonance (NMR) and mass spectrometry confirm the obtainment of the desired product in high yield and purity. The protonation behavior of the branched surfactant is not affected by alkyl tail branching, as shown by potentiometric titrations. In contrast, surface activity and aggregation behavior of C10DAO-branched is dramatically different from that of the linear analog N,N-dimethyldecyl-1-amine oxide (C10DAO-linear), in that it occupies a higher area at the solution interface and aggregates at much higher concentration, forming larger aggregates, as detected using tensiometry and dynamic light scattering (DLS), respectively. Aggregation behavior of C10DAO-branched is less sensitive to pH variations. Foaming tests show that C10DAO-branched is a more effective foam booster than its linear analog, in both acidic and basic solutions. The experimental results indicate that the branched surfactant can be used in applications that require enhanced and pH-independent surface activity and foamability. 相似文献
115.
Determination of inorganic trace elements in edible marine fish from Rio de Janeiro State, Brazil 总被引:2,自引:0,他引:2
Renata J. Medeiros Lisia Maria G. dos SantosAline S. Freire Ricardo E. SantelliAna Maria C.B. Braga Thomas M. Krauss Silvana do C. Jacob 《Food Control》2012,23(2):535-541
Fish and seafood may represent risk for human health since they can accumulate contaminants from aquatic environment and magnify them up the food chain. The purpose of this study was to analyze and evaluate the levels of aluminum, zinc, iron, manganese, cobalt, copper, arsenics, selenium, cadmium, barium, lead and bismuth in 11 fish species (Salmo salar, Sardinella brasiliensis, Pomatomus saltatrix, Micropogonias furnieri, Cynoscion leiarchus, Caranx crysos, Priacanthus arenatus, Mugil cephalus, Genypterus brasiliensis, Lopholatilus villarii and Pseudopercis numida) captured at Rio de Janeiro State Coast, Brazil. Concentration ranges (mg kg−1 of wet weight) of the selected elements were compared with those reported in other studies. In some cases, comparison of certain elements in the same fish species was difficult due to the lack of data. Aluminum concentration was significantly high in all samples and only M. cephalus, C. leiarchus e C. crysos presented arsenic concentrations below 1 mg kg−1, limit recommended by Brazilian legislation. 相似文献
116.
Labilloy D. Benisty H. Weisbuch C. Krauss T.F. Cassagne D. Jouanin C. Houdre R. Oesterle U. Bardinal V. 《Quantum Electronics, IEEE Journal of》1999,35(7):1045-1052
We report on the measurement of the diffraction efficiency of two-dimensional photonic-bandgap lattices consisting of a triangular array of circular air holes etched in a semiconductor waveguide. We use the spontaneous emission of the material as an internal point source. Combined with previous reflectivity and transmission measurements, the diffraction data allow us to assess the total amount of out-of-plane losses experienced by a guided wave traversing the dielectric lattice, as a function of the lattice pitch. We found that these losses are particularly weak for some range of parameters, especially in the photonic bandgap of interest. We discuss the reasons why they can be substantial with other parameters 相似文献
117.
Mahima Goel Marie Siegert Gert Krauss John Mohanraj Adrian Hochgesang David C. Heinrich Martina Fried Jens Pflaum Mukundan Thelakkat 《Advanced materials (Deerfield Beach, Fla.)》2020,32(43):2003596
Unlike the conventional p-doping of organic semiconductors (OSCs) using acceptors, here, an efficient doping concept for diketopyrrolopyrrole-based polymer PDPP[T]2-EDOT (OSC-1) is presented using an oxidized p-type semiconductor, Spiro-OMeTAD(TFSI)2 (OSC-2), exploiting electron transfer from HOMOOSC-1 to HOMOOSC-2. A shift of work function toward the HOMOOSC-1 upon doping is confirmed by ultraviolet photoelectron spectroscopy (UPS). Detailed X-ray photoelectron spectroscopy (XPS) and UV–vis–NIR absorption studies confirm HOMOOSC-1 to HOMOOSC-2 electron transfer. The reduction products of Spiro-OMeTAD(TFSI)2 to Spiro-OMeTAD(TFSI) and Spiro-OMeTAD is also confirmed and their relative amounts in doped samples is determined. Mott–Schottky analysis shows two orders of magnitude increase in free charge carrier density and one order of magnitude increase in the charge carrier mobility. The conductivity increases considerably by four orders of magnitude to a maximum of 10 S m−1 for a very low doping ratio of 8 mol%. The doped polymer films exhibit high thermal and ambient stability resulting in a maximum power factor of 0.07 µ W m−1 K−2 at a Seebeck coefficient of 140 µ V K−1 for a very low doping ratio of 4 mol%. Also, the concept of HOMOOSC-1 to HOMOOSC-2 electron transfer is a highly efficient, stable and generic way to p-dope other conjugated polymers. 相似文献
118.
M. A. Kaliteevski S. Brand R. A. Abram T. F. Krauss R. De La Rue P. Millar 《Journal of Modern Optics》2013,60(1):9-14
Abstract We report a method of designing aperiodic photonic quasicrystals. The method is based on the recognition that the Fourier transform of the dielectric structure has a direct influence on the mode spectrum, and can be chosen to enhance the properties of the system. The diffraction of light by, and the band structure of, such modified photonic quasicrystals is investigated and compared to the properties of conventional photonic quasicrystals. 相似文献
119.
Qualls Sara Honn; Scogin Forrest; Zweig Richard; Whitbourne Susan Krauss 《Canadian Metallurgical Quarterly》2010,4(2):85
Although small in number, current predoctoral programs in professional geropsychology offer models and training strategies that can guide future program development. Training opportunities exist within generalist programs as well as in geropsychology tracks within broader programs. This article explores the variety of ways by which predoctoral programs can facilitate development of foundational attitudes, knowledge, and skills that comprise the competencies in geropsychology. New programs can benefit from the guidance and ideas offered about how to accomplish professional geropsychology training within a variety of structures. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
120.
Azuelos G Barnabé-Heider M Behnke E Clark K Di Marco M Doane P Feighery W Genest MH Gornea R Guénette R Kanagalingam S Krauss C Leroy C Lessard L Levine I Martin JP Noble AJ Noulty R Shore SN Wichoski U Zacek V 《Radiation protection dosimetry》2006,120(1-4):499-502
The PICASSO project is a cold dark matter (CDM) search experiment relying on the superheated droplet technique. The detectors use superheated freon liquid droplets (active material) dispersed and trapped in a polymerised gel. This detection technique is based on the phase transition of superheated droplets at about room temperature and ambient pressure. The phase transition is induced by nuclear recoils when an atomic nucleus in the droplets interacts with incoming subatomic particles. This includes CDM particles candidate as the neutralino (a yet-to-discover particle predicted in extensions of the standard model of particle physics). Simulations performed to understand the detector response to neutrons and alpha particles are presented along with corresponding data obtained at the Montreal Laboratory. 相似文献