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51.
Claudia Penna Saveria Femmin Fabrizio Caldera Alberto Rubin Pedrazzo Claudio Cecone Edoardo Alfì Stefano Comit Takanobu Higashiyama Francesco Trotta Pasquale Pagliaro Roberta Cavalli 《International journal of molecular sciences》2021,22(8)
Heart failure (HF) prevalence is increasing among the aging population, and the mortality rate remains unacceptably high despite improvements in therapy. Myocardial ischemia (MI) and, consequently, ischemia/reperfusion injury (IRI), are frequently the basis of HF development. Therefore, cardioprotective strategies to limit IRI are mandatory. Nanocarriers have been proposed as alternative therapy for cardiovascular disease. Controlled reoxygenation may be a promising strategy. Novel nanocarriers, such as cyclic nigerosyl-nigerose (CNN), can be innovative tools for oxygen delivery in a controlled manner. In this study we analyzed new CNN-based formulations as oxygen nanocarriers (O2-CNN), and compared them with nitrogen CNN (N2-CNN). These different CNN-based formulations were tested using two cellular models, namely, cardiomyoblasts (H9c2), and endothelial (HMEC) cell lines, at different concentrations. The effects on the growth curve during normoxia (21% O2, 5% CO2 and 74% N2) and their protective effects during hypoxia (1% O2, 5% CO2 and 94% N2) and reoxygenation (21% O2, 5% CO2 and 74% N2) were studied. Neither O2-CNN nor N2-CNN has any effect on the growth curve during normoxia. However, O2-CNN applied before hypoxia induces a 15–30% reduction in cell mortality after hypoxia/re-oxygenation when compared to N2-CNN. O2-CNN showed a marked efficacy in controlled oxygenation, which suggests an interesting potential for the future medical application of soluble nanocarrier systems for MI treatment. 相似文献
52.
Mertens W. G. Rubin L. J. Teasdale B. F. 《Journal of the American Oil Chemists' Society》1961,38(6):286-289
A fractional crystallization method for the winterization of cottonseed oil with solvents was developed in our laboratories
and pilot plant.
Small amounts of solvent (e.g., 10% by weight of acetone) were mixed with the oil. This mixture was rapidly chilled to 0°C. and kept at this temperature
for 3–4 hrs.; the liquid portion was separated from the solids.
After solvent evaporation a salad oil of good quality was obtained. The yield is equal to or better than that obtained with
conventional methods.
The method is suitable for a continuous operation since rapid chilling can be used, and only a short over-all time is necessary.
Great advantages of the process are the use of low amounts of solvent and of a refrigeration system not requiring temperatures
below 0°C. 相似文献
53.
M. Rubin Z. Halpern A. Livoff A. Wennberg A. Tietz E. Antebi D. Lichtenberg 《Lipids》1992,27(5):321-325
This study was undertaken to determine the effect of various lipid emulsions on the hepato-biliary system in rats. Rats were
randomly divided into six groups and infused continuously for 48 hr with either long-chain triglycerides (LCT), medium-chain
triglycerides (MCT) or a mixture of MCT and LCT. One group infused with physiological saline solution served as controls.
Throughout this period the rats received a fat free dietad libitum. During the last hour of lipid infusion bile was collected for determination of bile flow and composition. Subsequently,
the rats were sacrificed and the morphology and lipid content of the liver determined. Only LCT lipid emulsions induced morphological
changes and increased liver cholesterol content. In two rats infused with radiolabeled LCT, no labeled cholesterol was found
in the liver, indicating that the excess hepatic cholesterol level may originate from enhanced cholesterol mobilization to
the liver. Biliary cholesterol and phospholipid concentrations in LCT-treated rats were also elevated, as was the lithogenic
index, whereas the other emulsions had no such effects. None of the emulsions affected the plasma liver function tests or
bile flow. We therefore conclude that the lithogenicity of the bile in rats is directly related to the lipid components of
the total parenteral nutrition and the type of triglyceride infused. 相似文献
54.
The action of the tumor promoter, phorbol 12,13-dibutyrate (PDBu), on rabbit peritoneal and human neutrophils is associated
with stimulation of14C-arachidonic acid incorporation into phospholipids within 1–2 min. Stimulated14C-arachidonate incorporation was relatively selective for phosphatidylinositol (PI) in rabbit neutrophils. In contrast, the
secretory response of human neutrophils to PDBu coincided with stimulated label incorporation into phosphatidylserine (PS),
phosphatidylcholine (PC), phosphatidylethanolamine (PE), phosphatidic acid (PA) and PI. Significant increases in label incorporation
were observed with PDBu concentrations as low as 2 nM, and the dose response of stimulated label incorporation paralleled
that of evoked lysozyme secretion. A parallel, but partial, inhibition of PDBu-stimulated PI labeling and enzyme release was
observed after exposing rabbit neutrophils to calcium-deprived medium, whereas calcium deprivation failed to significantly
depress either of these stimulant actions of PDBu in human neutrophils. Further, in rabbit neutrophils PDBu elicited an increase
in cell associated45Ca. However, PDBu was unable to promote the incorporation of32P orthophosphate into PI or enhance phospholipase A2 activity in broken cells. These findings suggest that one expression of the interaction between phorbol esters and their
receptors on neutrophils involves the turnover of arachidonic acid in phospholipids. This stimulated turnover of arachidonate
may be a critical step in the cascade of events associated with neutrophil activation. 相似文献
55.
Zirconia and yttria films were sputter deposited onto unheated fused silica substrates using a metal target and rare gas-oxygen discharges. Double-beam spectrophotometry was used to measure the transmission and reflection as a function of incident photon energy, E , from which the absorption coefficient, α( E ), was calculated. An indirect interband transition at E i = 4.70 eV and two direct interband transitions at E g1 = 5.17 eV and E g2 = 5.93 eV occur in monoclinic zirconia. Two direct interband transitions at E g1 = 5.07 eV and E g2 = 5.73 eV occur in cubic yttria. The absorption edge structure is modified when unusual phases, such as tetragonal zirconia, and zirconia and yttria with no longrange crystallographic order, are present. 相似文献
56.
Supported gold catalysis in the hydrogenation of canola oil 总被引:1,自引:0,他引:1
L. Caceres L. L. Diosady W. F. Graydon L. J. Rubin 《Journal of the American Oil Chemists' Society》1985,62(5):906-910
The catalytic activity of gold supported on silica orγ-alumina has been studied in the hydrogenation of canola oil. In the hydrogenation of butadiene and pentene using these catalysts,
high stability, low yield oftrans-isomers and high monoene selectivity have been reported in the literature.
Catalysts containing 1% and 5% Au w/w on porous silica andγ-alumina were active in hydrogenating canola oil in the range of 150 to 250 C and 3550 to 5620 kPa. The activity level of
these catalysts was about 30 times lower than that shown by the standard AOCS Ni catalyst based on the concentration of metal
(g Au/L oil). Up to 91% monoene content was obtained using these catalysts in comparison with a maximum of 73% for the AOCS
standard Ni catalysts. Gold catalysts can be recovered easily by filtration and reused several times without a decrease in
activity. The hydrogenated oil was nearly colorless. No gold was detectable in the oil. Contrary to claims in the patent literature,
the gold catalyst produces higher concentrations oftrans-isomers than does nickel. However, using gold catalysts the complete reduction of linolenic acid in canola oil can be achieved
at a lowertrans-isomer content in the products than that obtained by using the AOCS standard nickel catalyst. 相似文献
57.
Guided by the Uses and Gratifications (U&G) perspective, this study examined the influence of unwillingness to communicate, loneliness, Internet-use motives, and Internet (CMC) use and interaction (amount and types of use and self-disclosure) in online communication satisfaction and online relationship closeness. There were 261 participants in this study. Overall, participants who perceived their face-to-face communication to be rewarding, used CMC for self-fulfillment, and disclosed their personal feelings to others tended to feel close to their online partners. Moreover, those who used the Internet for purposes of self-fulfillment and affection and intended to disclose their feelings to others felt satisfied with their online communication. The associations among the constructs extend our knowledge of the U&G theoretical model, how and why people communicate interpersonally in CMC settings, and the influence of individual differences on CMC for relational communication. 相似文献
58.
利用随机相变动力学理论研究运动认知的神经网络动力学模型.给出了感觉神经元集群、中间神经元集群和运动皮层神经元集群在耦合条件下相互作用、相位编码和数密度随时间的演化.探讨了神经网络在自发运动条件下以及在刺激条件下的神经网络动力学响应.通过数值模拟证实了(1)Walter J.Freeman提出的皮层动力学响应不能够编码外刺激信息的猜想;(2)串行的神经网络系统的神经编码具有节律编码的性质;(3)在中枢神经系统的调控中,神经抑制有其重要的作用. 相似文献
59.
60.
大脑神经元的活动是在复杂的生理学环境下工作的,而生理学环境中的噪声来源于多个方面.如何定量地正确评估神经系统中的噪声环境是神经信息处理的基本问题.本文通过神经能量的计算给出了噪声对神经元膜电位及对应的能量波形产生显著影响的临界值的估计范围,从而定义了神经元赖以活动的生理学意义上的噪声环境. 相似文献