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991.
Subsolidus Phase Relationships in Part of the System Si,Al,Y/N,O: The System Si3 N4 ─AIN─YN─Al2 O3 ─Y2 O3
Wei-Ying Sun Tseng-Ying Tien Tung-Sheng Yen 《Journal of the American Ceramic Society》1991,74(11):2753-2758
The subsolidus phase relationships in the system Si,Al,Y/N,O were determined. Thirty-nine compatibility tetrahedra were established in the region Si3 N4 ─AIN─Al2 O3 ─Y2 O3 . The subsolidus phase relationships in the region Si3 N4 ─AIN─YN─Y2 O3 have also been studied. Only one compound, 2YN:Si3 N4 , was confirmed in the binary system Si3 N4 ─YN. The solubility limits of the α'─SiAION on the Si3 N4 ─YN:3AIN join were determined to range from m = 1.3 to m = 2.4 in the formula Y m /3 Si12- m Al m N16 . No quinary compound was found. Seven compatibility tetrahedra were established in the region Si3 N4 ─AIN─YN─Y2 O3 . 相似文献
992.
Meiling Wan Shuifeng Liu Da Huang Yang Qu Yang Hu Qisheng Su Wenxu Zheng Xianming Dong Hongwu Zhang Yen Wei Wuyi Zhou 《应用聚合物科学杂志》2021,138(13):50114
Polylactic acid (PLA) has become a popular polymer material due to its superior biocompatibility. At present, there are a few relevant research on heterogeneous bone powder. Besides, the poor dispersibility and adhesivity of inorganic particles in the organic phase remains a problem. In this study, the pork bone powders were modified with N-butanol to improve its dispersibility and compatibility in the PLA matrix. In addition, polybutylene succinate-co-terephthalates (PBSA) was applied as a flexibilizer to further reinforce the mechanical properties of materials. The composite filaments with a diameter of 1.75 ± 0.05 mm containing 10 wt% of modified bone powder, 10 wt% PBSA and 80 wt% PLA were prepared by a melt blending method. The obtained results showed that modified particles were uniformly dispersed within the PLA matrix and improved the mechanical properties of the composite filaments with a tensile strength of 48.5 ± 0.2 MPa and a bending strength of 79.1 ± 0.1 MPa and a notch impact strength of 15.8 ± 0.3 kJ/m2. And the prepared composite materials contained low cytotoxicity, high biocompatibility and printability, which verified the feasibility of it in 3D printing personalized bone repair applications. This provides a theoretical basis for further research on the effect of bone repair in vivo. Therefore, the composite material will have potential applications such as making customized bones and bone scaffolds by three dimensional printing technology. 相似文献
993.
Autonomous temporal linguistic rule extraction is an application of growing interest for its relevance to both decision support systems and fuzzy controllers. In the presented work, rules are evaluated using three qualitative metrics based on their representation on the truth space diagram. Performance metrics are then treated as competing objectives and the multiple objective evolutionary algorithm is used to search for an optimal set of nondominant rules. Novel techniques for data pre-processing and rule set post-processing are designed that deal directly with the delays involved in dynamic systems. Data collected from a simulated hot and cold water mixer are used to validate the proposed procedure. 相似文献
994.
Omari E Ansong Susan Jansen Yen Wei Gregory Pomrink Hui Lu Alpa Patel Shuxi Li 《Polymer International》2009,58(1):54-65
BACKGROUND: Nitroxide adducts 1,1‐ditertbutyl‐1‐(1‐methyl‐1‐cyanoethoxy)‐amine (AIBN/DBN), 1,1‐ditertbutyl‐1‐(benzoylperoxy)‐amine (BPO/DBN) and 2,2,6,6,‐tetramethyl‐4‐oxo‐1‐(1‐methyl‐1‐cyanoethoxy)‐piperidine (AIBN/4‐OXO‐TEMPO) were prepared and evaluated as stabilized unimolecular initiators for controlled radical polymerization of methacrylate monomers using sulfuric acid as an accelerating additive. Their effectiveness was evaluated from polymerization rates, molecular weight control and dispersity (D) of the polymers. Thermal stabilities of the polymers were also examined. The monomers used were methyl methacrylate, triethylene glycol dimethacrylate (TEGDMA) and ethoxylated bisphenol A dimethacrylate (EBPADMA). RESULTS: Polymerization was accomplished at 70 and 130 °C in 5 min to 144 h. The value of D of poly(methyl methacrylate) (PMMA) was 1.05–1.22. The glass transition temperature (Tg) for PMMA was 122–127 °C. The activity of the chain ends was established by chain extension and controlled polymerization was established by plotting Mn versus monomer conversion. First‐order kinetics in monomer consumption was established and an electron paramagnetic resonance study was conducted. Decomposition temperature (Td) for PMMA was 360–380 °C, for poly(TEGDMA) was 300–380 °C and for poly(EBPADMA) was 360–440 °C. Photoinitiation without additive yielded no polymer. Thermal initiation by AIBN/4‐OXO‐TEMPO was the fastest. CONCLUSIONS: The initiators are applicable in low‐temperature additive‐enhanced controlled polymerization of methacylates and dimethacrylates, producing polymers with excellent attributes and a low value of D. Copyright © 2008 Society of Chemical Industry 相似文献
995.
996.
Ratings relating stage and flow discharge have been traditionally established through measurements of discharge and concurrent stage. Inherent in this approach are several difficulties and shortcomings that have resulted in widely recognized problems in developing and applying ratings, such as looped ratings. Purely empirical methods that attempt to improve the agreement between ratings and measurements have met with limited success. This paper suggests a theoretical basis for discharge ratings that reflects the hydraulics of unsteady, nonuniform, subcritical flow. Simplification of the Saint-Venant equations for rating applications results in an approximation of the dynamics of flow that is summarized in the hydraulic performance graph, from which discharge ratings can be developed and updated theoretically. The resulting ratings apply a quasi-steady approximation of the flow, along with semiempirical correction factors developed for the site to estimate the discharge using the same information that is needed for “stage-fall-discharge ratings,” while addressing some of the shortcomings of this type of rating. Comparison of ratings developed using the resulting procedure against laboratory and field observations yields encouraging results. 相似文献
997.
Jih‐Hung Pan Yi‐Song Chen Lee‐Yen Sheen Been‐Huang Chiang 《Journal of the science of food and agriculture》2008,88(13):2223-2230
BACKGROUND: Submerged cultivation of Antrodia cinnamomea was carried out for manufacturing the fermentation product with anti‐hepatoma activity. The fermentation process was optimized for different parameters at shake flask level to obtain products with high inhibition potency against Hep G2 hepatoma cells. Scale‐up of the fermentation process was then achieved from 250 mL shake flask to 5 L, 500 L and 5‐ton fermenters. RESULTS: Glucose and malt extract were found to be the best carbon and nitrogen sources, respectively. The initial pH of 5.0 and an operating temperature of 22 °C were the best for a product with lowest IC50 value. A shorter cultivation time was required when the scale of fermentation increased from 5 L to 5 tons. The reducing sugar and solids contents of the broth filtrate were correlated exponentially with the IC50 of the ethanolic extract of mycelium for hepatoma cells, and the level of ergosterol in the mycelium extract follows the same profile as the increase in Hep G2 cells inhibition. CONCLUSION: When Antrodia cinnamomea is cultured in a 5‐ton fermenter, 4 weeks are required for the fermentation product to reach the highest anti‐hepatoma activity. The solid and reducing sugar contents of the broth filtrate as well as the ergosterol content in the ethanol extract of mycelium can serve as the marker during fermentation for manufacturing product with anti‐hepatoma activity. Copyright © 2008 Society of Chemical Industry 相似文献
998.
The study was focused on the thermal degradation behavior of epoxy resins (EP) blended with propyl ester phosphazene (FR). The analysis studied the evolved gas and the residual char yield using different techniques. The results showed that pure epoxy resin and their blends were all a one‐stage thermal degradation reaction. The major degradation temperature of blends was lower than the temperature of pure epoxy resin, but the residual char yield of epoxy blends at 550°C was higher than that of pure epoxy resin. FR could accelerate the production of small molecules such as acetone, phenol, and isopropyl phenol during thermal degradation process. Honeycomb structure compounds were also formed in the residual char of epoxy and its blends. Additionally, elemental analysis of the residual char yield showed that phosphorus was a residual element, and other elements mostly diffused to the evolved gas. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 81: 1161–1174, 2001 相似文献
999.
The creation of a stylistic animation through the use of high‐level controls has always been a design goal for computer animation software. In this paper, we propose a procedural animation system, called rhythmic character animation playacting (RhyCAP), which allows a designer to interactively direct animated characters by adjusting rhythmic parameters such as tempo, exaggeration, and timing. The motions thus generated reflect the intention of the director and also adapt to environmental obstacle constraints. We use a sequence of martial‐art steps in the performance of a Chinese lion dance to illustrate the effectiveness of the system. The animation is generated by composition of common motion elements, concisely represented in an action graph. We have implemented an animation control program that allows Chinese lion dance to be choreographed interactively. This authoring tool also serves as a useful means for preserving this part of world cultural heritage. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献
1000.
CC Yen CH Tzeng JH Liu TJ Chiou RK Hsieh WS Wang PM Chen 《Canadian Metallurgical Quarterly》1997,60(4):213-218
The antigenic components of Fasciola gigantica somatic extract were revealed by sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE) and immunoblotting technique using sera from patients with F. gigantica infection, patients with clinically diagnosed fascioliasis, patients with other infections/illness and healthy adults. By SDS-PAGE, it was found that the somatic product comprised more than 22 polypeptides. Immunoblotting analysis revealed at least 13 components which were strongly recognized by sera of patients with fascioliasis. These antigenic components had molecular weights ranging from less than 14.4 to more than 94 kDa. One antigenic component, i.e. 38 kDa was found to give a consistent reaction with sera of patients with fascioliasis (100% sensitivity and 96.7% specificity). The finding suggests that the 38 kDa components may be a potential diagnostic antigen for fascioliasis. 相似文献