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991.
Metformin (MTF) is one of the most common oral agents used to treat diabetes mellitus. Intoxication is associated with lactic acidosis and has significant clinical consequences. We report 12 cases requiring dialytic intervention. Twelve patients were analyzed from 2005 to 2010; 10 of these patients were treated with dialysis. Conventional hemodialysis (HD) and continuous veno-venous hemodialysis treatments with bicarbonate dialysis were used, and the results were presented as mean and standard deviation. The results are as follows: 33% of the patients were male, hospital stay was 9.3 (± 12) days, average MTF dose 1.7 g/day, mortality was 25%. Baseline glomerular filtration rate for these patients was 51.5?mL/min, with an average age of 64 (± 11) years. On presentation, all had acute kidney injury with blood urea nitrogen/creatinine 75 (± 30)/8.1 (± 3.7) mg/dL, lactic acid 12.4 (± 8.1) mmol/L, pH?7.04 (± 0.19), bicarbonate 7.2 (± 4.5) mmol/L. Metformin level was 25 (± 17) μg/mL; anion gap was 28 (± 9), and serum potassium was 5.4 (± 1.3) mEq/L. Seventy percent of patients were treated with conventional HD. Patients required 4 (± 5) dialysis treatments at blood flow QB 330 (± 53), dialysis flow QD 571 (± 111) for 305 (± 122) minutes. Postdialysis, the acidosis parameters improved: bicarbonate 19.2 (± 4.1) mmol/L, lactic acid 6 (± 4) mmol/L and MTF levels decreased 8.9 (± 5.7) μg/mL. Metformin percentage removal was calculated to be 60% (± 24). No difference was found between HD and continous veno-venous hemodialysis. The only difference between survivors was the age 53 (± 7) vs. 78 (± 10) (P?相似文献   
992.
Biocompatibility is of paramount importance for drug delivery, tumor labeling, and in vivo application of nanoscale bioprobes. Until now, biocompatible surface processing has typically relied on PEGylation and other surface coatings, which, however, cannot minimize clearance by macrophages or the renal system but may also increase the risk of chemical side effects. Cell membranes provide a generic and far more natural approach to the challenges of encapsulation and delivery in vivo. Here we harness for the first time living cells as "factories" to manufacture cell membrane capsules for encapsulation and delivery of drugs, nanoparticles, and other biolabels. Furthermore, we demonstrate that the built-in protein channels of the new capsules can be utilized for controlled release of encapsulated reagents.  相似文献   
993.
In this study, we prepared magnetic iron oxide and gold/iron oxide nanoparticles (NPs) and characterized their morphologies and properties by XRD, TEM, EDX, VSM and UV-vis measurements. The magnetite iron oxide NPs of 10 nm were synthesized by coprecipitation of Fe2+ and Fe+3 in the solution of NH4OH and then they were used as seed particles for the subsequent growth to prepare the magnetite NPs of different particle sizes and also to prepare gold/iron oxide composite NPs. All those magnetite NPs are superparamagnetic and the gold/iron oxide composite NPs combine the optical and magnetic properties, which are contributed by gold and iron oxide components, respectively.  相似文献   
994.
The ageing of the metallization layers of power semiconductor dies may be the cause of failure of power semiconductor modules. Usual indicators of failure like on-state voltage drops make it difficult to highlight the deterioration of the metallization layer. In this study, we evaluate the relevance of the characterization of power device metallizations by means of the eddy current sensors. Experimental results show the ability to monitor the state and the evolution of the metallization ageing with such a technique.  相似文献   
995.
This study deals with the design and development of calculational techniques and evaluation of key neutronic parameters of a typical PWR core having a total reactor power of 2652 MWt (890 MWe). The PWR core consists of 157 fuel assemblies containing a total of ∼72 tons of uranium arranged vertically in a concentric square array within the core shroud. Each fuel assembly contains 264 UO2 fuel pins with various enrichments (2.1, 2.6 and 3.1%), 24 control rods of Gd2O3 and one central water channel and all are arranged in a 17 × 17 array of matrix. Different computer codes including WIMS, TWOTRAN, CITATION and MCNP have been employed to develop a versatile and accurate reactor physics model of the PWR core. The computational methods, tools and techniques, customization of cross section libraries, various models for cells and super cells, and a lot of associated utilities have been standardized and established/validated for the overall core analysis. The analyses were performed in 3 steps: firstly for fuel pincells, then for the fuel assemblies and finally for the whole core. The WIMS and MCNP calculated infinite multiplication factors for fuel pincells having 2.1% enriched 235U were found to be 1.23393 and 1.23654, for 2.6% enrichment 1.28635 and 1.28887, and finally for 3.1% enrichment 1.32481 and 1.32812, respectively. For fuel assembly, WIMS and MCNP calculated infinite multiplication factors having 2.1% enrichment were found to be 1.24853 and 1.25445, for 2.6% enrichment 1.30372 and 1.30992, and for 3.1% enrichment 1.34424 and 1.35041, respectively. The effective multiplication factor calculated by CITATION, TWOTRAN and MCNP for whole core were found to be 1.25580, 1.25909 and 1.26382, respectively. The peak thermal neutron flux in the core calculated by MCNP was found to be 5.0298 × 1014 neutrons/cm2 s and the average core power density was 17.1 kW/cm3. The calculated results from different codes were found to be very good agreement for different moderator conditions. The choice of computer codes like WIMSD, TWOTRAN, CITATION and MCNP which are being used in nuclear industry for many years were selected to identify and develop new capabilities needed to support PWR analysis. The ultimate goal of the validation of the computer codes for PWR applications is to acquire and reinforce the capability of these general purpose computer codes to perform the core design and optimization study.  相似文献   
996.
Core/shell structured CePO4:Tb(III) @LaPO4 and CePO4:Tb(III) were successfully synthesized in tris(2-ethylhexyl) phosphate(TEHP) and diethylene glycol(DEG) solvents for comparison of the two techniques in open air and closed reaction vessel.Morphology and crystal structure of the core/shell nanophosphors were determined by using X-ray diffraction(XRD) and transmission electron microscopy(TEM) ,which showed that nanophosphors had diameter of about 5-10 nm with the monoclinic monazite phase.The nanophosphors ...  相似文献   
997.
In order to make an automobile body structure, incremental sheet metal forming is introduced as a rapid prototyping process. Numerical modeling of the process is initially used to predict the deformation of the sheet metal to avoid failure during the incremental forming process using ABAQUS/Explicit finite element code and OYANE's ductile fracture criterion via a VUMAT user material. An automobile CAD model is then designed, and segmented into several parts in order to accommodate the working space of the CNC machine and formability of sheet metal. After that, CAM software is used to generate a tool‐path for making wooden‐dies and all small parts. Finally, a welding process is applied to join all parts which were cut by laser cutting after incremental sheet forming process.  相似文献   
998.
Starch digestion is mostly investigated with in vitro techniques, and time‐course measurements are common. These yield digestograms that are modeled by theoretical, semitheoretical, and empirical kinetic equations, many of which are reviewed here. The Duggleby model has Michaelis–Menten functions, and its dependent variable is on both sides of the equation with no apparent parameter for maximum digestible starch (D). The Gaouar and Peleg models are equivalent. They predict both the initial digestible starch (D0) and D, and an average digestion rate, but they can reveal "biratial" digestions. The first‐order kinetic model exhibits diverse predictabilities and, when linearized, D is sometimes equated to 100 g/100 g dry starch (100%), it yields an average rate of digestion and can predict negative D0. The log of slope (LOS) model is unique in revealing the rapid‐to‐slow digestion rate phenomenon, but without guidelines to identify such. The LOS model does not sometimes use all the digestogram data, can predict D greater than 100%, and returns zero digestion rate for some digestograms. However, some starchy materials exhibit a slow‐to‐rapid digestion rate phenomenon, as demonstrated with an example. The modified first‐order kinetic model uses all the digestogram data with practical constraints (D0 ≥ 0 g/100 g dry starch; D ≤ 100 g/100 g dry starch), describes all digestograms, and yields an average digestion rate, but it can also be used for "biratial" digestions. In addition, the logistic and Weibull models are discussed. Using some published data, the computational characteristics of these commonly used models are presented with objective parameters to guide choices.  相似文献   
999.
Nguyen  My Tuyen T.  Seo  Nari  Kim  Yong-Ki  Jung  Ji A.  An  Hyun Joo  Kim  Jung-Min  Song  Young-Ha  Kim  Jaehan  Yoon  Jong-Won 《Food science and biotechnology》2022,31(13):1661-1666
Food Science and Biotechnology - Despite health benefits reported recently, 2′-fucosyllactose (2′-FL) concentration in maternal milk was not conclusively reported because it varies...  相似文献   
1000.
Food Science and Biotechnology - The plant Morinda citrifolia L. (Noni) has been the subject of several recent research due to its positive impact on the treatment and prevention of a variety of...  相似文献   
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