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1.
Lately we have seen quite a few Microsoft vulnerabilities — the most noteworthy being the Object Data vulnerability, which Microsoft attempted to fix with the patches in security bulletin MS03-032. The Object Data vulnerability is extremely easy to exploit — like MS01-020 which is still being exploited by many viruses (e.g. ‘Swen’ currently roaming the Internet). The vulnerability has already beenexploited by a spammer, who wanted to promote his porn site and by a hacker, who compromised an online hotel.  相似文献   
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Three different methods for the simultaneous analysis of surface phenotype and DNA quantification were compared. One method, involving the fixation of cells in 70% ethanol, was convincingly superior, both with regard to the CV of the G0G1 peak and the intensity of the DNA labelling. Furthermore, the correlation between the surface antigen densities before and after fixation were high. Experiments evaluating the intraday and the interday variation of the DNA ratio (the mean channel of the G0G1 peak of the sample divided by the mean channel of the G0G1 peak of chicken erythrocytes), documented the former to be small, with S.D. values varying from 0.0 to 0.016, while the latter were considerably higher with S.D. values varying from 0.077 to 0.123. Since the intraday variation of the DNA ratio was consistently low and the interday variation strongly correlated to the position of the red fluorescence test beads, it was possible to minimize the interday variation of the DNA ratio, by calculating the DNA index as the ratio between the DNA ratio of the sample and that of an external control (buffy coat leukocytes). Analyzing normal bone marrow and calculating the DNA index (DI) on the basis of these ratios, the confidence limits of the DI were decreased by more than half the values obtained when DI calculation was based solely on an internal standard, thereby making subsequent ploidy determinations of patient samples more precise. We conclude that this setup of internal and external standards allows accurate determinations of DNA aneuploidy even in an assay where whole cells labelled for surface antigen and DNA content are analyzed.  相似文献   
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Creative processes are complex and consist of sub‐processes, e.g. value creation, scaffolding, imagination and materialization. Creativity takes place in a physical context, i.e. in a confined space. Such space restricts and enables the free flow of sensory experiences and proximity of other people. The confinements may make certain sensory experiences available, e.g. vision of source material, sight and sound (including noise). This framing allows certain cognitive processes and restricts others. This may induce emotions that, in turn, facilitate or reduce the enhancement of creativity. Physical space affects the well‐being of people, the channels of information, the availability of knowledge tools and sets the stage for coherence and continuity, which may contribute to competitive advantages.  相似文献   
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A melt pelletization process was investigated in an 8 litre laboratory scale high shear mixer using a formulation with paracetamol, glyceryl monostearate 40-50, and microcrystalline wax. The effects of jacket temperature, product temperature during massing, product load, massing time and impeller speed were investigated by means of factorially designed experiments. The maximum yield of pellets in the range of 500-1400μm was found to approx. 90%. For process conditions preventing deposition of moist mass, the process was found to be reproducible. Impeller speed and massing time were found to be important process variables. Remarkably low in vitro drug release rates were observed in USP-dissolution tests.  相似文献   
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The mechanical properties of moist samples of fine, polydisperse powders are investigated by measuring the tensile strength by a diametrical compression test and the stress—strain relationship of samples exposed to uniaxial compression. The strengths determined by the two methods correlate well. The strength of moist samples compressed to porosities comparable to the level of intragranular porosities achieved by granulation in high-speed mixers is shown to be influenced significantly by particle interactions in addition to mobile liquid bondings. For a particular material the strength is controlled mainly by porosity and liquid saturation. It is shown that the effect of a growing liquid saturation is to reduce particle interactions and thus to facilitate densification during granulation. The deformability of moist samples, which is dependent on strength and deformation behaviour, is assessed for lactose and dicalcium phosphate.  相似文献   
8.
Lipozyme TL IM-catalyzed interesterification for the modification of margarine fats was carried out in a batch reactor at 70°C with a lipase dosage of 4%. Solid fat content (SFC) was used to monitor the reaction progress. Lipase-catalyzed interesterification, which led to changes in the SFC, was assumed to be a first-order reversible reaction. Accordingly, the change in SFC vs. reaction time was described by an exponential model. The model contained three parameters, each with a particular physical or chemical meaning: (i) the initial SFC (SFC0), (ii) the change in SFC (ΔSFC) from the initial to the equilibrium state, and (iii) the reaction rate constant value (k). SFCo and ΔSFC were related to only the types of blends and the blend ratios. The rate constant k was related to lipase activity on a given oil blend. Evaluation of the model was carried out with two groups of oil blends, i.e., palm stearin/coconut oil in weight ratios of 90∶10, 80∶20, and 70∶30, and soybean oil/fully hydrogenated soybean oil in weight ratios of 80∶20, 65∶35, and 50∶50. Correlation coefficients higher than 0.99 between the experimental and predicted values were observed for SFC at temperatures above 30°C. The model is useful for predicting changes in the SFC during lipase-catalyzed interesterification with a selected group of oil blends. It also can be used to control the process when particular SFC values are targeted.  相似文献   
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Release of intracellular enzymes to the extracellular space is a marker of cell damage in various diseases, e.g. liver, heart and muscle diseases. In the normal state the plasma membrane is impermeable to enzymes, and enzyme release, therefore, indicates a severe change of the membrane integrity. This review deals with the present knowledge about cellular changes leading to enzyme release, which may be caused either by energy depletion, e.g. in ischemia or shock, or by a direct membrane damage as caused by various toxins and inflammatory products. Inhibition of the energy metabolism results in ATP depletion leading to fluxes of Na+, K+ and Cl- down their gradients across the membrane and swelling of the cell. Subsequently Ca2+ leak into the cell activating phospholipases and the formation of eicosanoids, affecting the cytoskeleton and, perhaps, activating the formation of oxidants. The exact "point of no return" is not known but an uncontrolled Ca2+ activity in the cell probably has an important role in initiating the irreversible changes. The result of these reactions and probably other unknown reactions as well is damage to the membrane. This is evident morphologically at first by the formation of blebs that appears in the reversible phase, and later on by rupturing of the membrane, a sign of irreversible damage. A very small part of the enzyme release may occur in the reversible phase when blebs detach with resealing of the membrane, but the substantial part of enzyme release occurs as a result of irreversible cell damage when ATP has decreased to a low level and a serious disruption of the membrane integrity has taken place. All the secondary affections of the membrane during energy depletion may also occur as a primary direct membrane damage that more or less may affect the energy metabolism secondarily. The cell damage and enzyme release after some types of direct membrane damage is almost independent of the cellular energy metabolism whereas other types of direct membrane damage are counteracted by the cell by energy consuming reactions and, therefore, the final cell damage is a concerted action of the direct membrane damage and the energy depletion. This also means that a direct membrane damage may be more severe for the cell in energy depleted states than in the normal state. As in energy dependent cell damage the substantial part of enzyme release after a direct membrane damage is due to irreversible cellular changes. It appears that although the knowledge of the molecular basis of cell damage and enzyme release has grown there are still many questions to be answered about these complex processes.  相似文献   
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