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101.
In this paper, we propose a new continuous self‐collision detection (CSCD) method for a deformable surface that interacts with a simple solid model. The method is developed based on the radial‐view‐based culling method. Our method is suitable for the deformable surface that has large contact region with the solid model. The deformable surface may consist of small round‐shaped holes. At the pre‐processing stage, the holes of the deformable surface are filled with ghost triangles so as to make the mesh of the deformable surface watertight. An observer primitive (i.e. a point or a line segment) is computed so that it lies inside the solid model. At the runtime stage, the orientations of triangles with respect to the observer primitive are evaluated. The collision status of the deformable surface is then determined. We evaluated our method for several animations including virtual garments. Experimental results show that our method improves the process of CSCD. 相似文献
102.
北京市雨水收集利用蓄水池容积计算与分析 总被引:1,自引:0,他引:1
基于北京市1984—2013年的日降雨资料,以北京林业大学林业楼及其周边绿地为研究区,设置3种用水情景(冲厕、绿地灌溉及冲厕+绿地灌溉),采用连续模拟法,分别绘制3种用水情景下雨水收集利用工程的雨水截留率、自来水替代率、供水保证率以及效益费用比变化曲线,并通过综合分析这些曲线的变化特征确定雨水蓄水池最佳设计容积(60~82 m3)。同时采用设计暴雨法计算1~5年不同重现期的蓄水池设计容积(77~248 m3)。结果表明,连续模拟法计算过程相对复杂,但可用于综合衡量雨水收集利用工程的雨洪管理效益,以及缓解水资源短缺效益、供水可靠性及经济可行性分析。 相似文献
103.
通过正交实验,研究了γ-Al2O3载体制备中拟薄水铝石水洗的连续化。方差分析表明,第一阶段洗水的pH是影响脱氯效果的关键因素,初步得出水洗连续化的优化条件。与国内外传统的间歇式水洗相比,收率从80%提高到99.7%,所需洗水量仅为原来的1/3,而处理500 kg物料的生产周期也从10 h缩短到2~3 h。 相似文献
104.
105.
为解决动态环境中移动点的连续反向最近邻查询问题,将连续反向最近邻查询分为单色和双色2种情况进行研究。利用移动点Voronoi图,分别给出单色连续反向最近邻查询算法、双色连续反向最近邻查询算法以及相关定理,对算法正确性和可终止性进行证明,分析算法时间复杂性。按照移动点Voronoi图的拓扑结构是否改变分为2种情况,分析每种情况下候选所在区域的变化,在变化区域内进行Voronoi图的重构,得到对应的解决方法。在多数情况下,该算法只需生成局部移动点的Voronoi图即可找到结果,减小了连续反向最近邻查询的代价。 相似文献
106.
107.
William E. Cooper Jr. 《Journal of chemical ecology》1991,17(5):849-863
The ability to discriminate prey chemicals from control substances and the presence of a poststrike elevation in tongue-flicking (PETF) rate are experimentally demonstrated in the lacertid lizard,Podarcis muralis, The tongue-flick attack score, a composite index of response strength, was significantly higher in response to integumental chemicals from cricket than to cologne or distilled water. The cricket chemicals additionally elicited a significantly greater rate of tongue-flicking and higher proportion of attacks by the lizards than did control stimuli. PETF combined with apparent searching movements strongly suggest the presence of strike-induced chemosensory searching (SICS). Experimental evidence indicates that both PETF and SICS occur in insectivorous representatives of three families of actively foraging autarchoglossan lizards, suggesting their widespread occurrence in such lizards. The adaptive roles of chemosensory behavior in the foraging behavior of P.Muralis are discussed. It is proposed that these lizards may form chemical search images and that PETF and SICS may have been present in the lacertilian ancestors of snakes. 相似文献
108.
109.
Two monophagous sawflies,Neodiprion dubiosus andN. rugifrons, actively avoid feeding on the current season's needles of jack pine,Pinus banksiana, while the polyphagousN. lecontei feeds indiscriminately on foliage of all age classes. Bioassay studies with needle extracts indicate thatN. dubiosus andN. rugifrons larval feeding preference is governed by a group of tricyclic diterpene resin acids. Resin acids commonly occur in needles of all ages; however, levopimaric, palustric, dehydroabietic, and neoabietic acids were at higher concentrations in the new needles.N. dubiosus was significantly deterred from feeding on 1-year-old foliage when treated with the pure resin acids, palustric and levopimaric, at 0.5 and 1.0 mg/ml MeOH.N. rugifrons larvae were deterred from feeding by pure dehydroabietic, neoabietic, and palustric acids at 1.0 mg/ml MeOH. 相似文献
110.
John I. Glendinning 《Journal of chemical ecology》1992,18(9):1559-1575
I compared the feeding responses of five species ofPeromyscus mice (aztecus, polionotus, melanotis, leucopus, andmaniculatus) to three bitter-tasting cardenolides (ouabain, digoxin, and digitoxin) that differ greatly in lipophilic character.Peromyscus, like other muroid rodents, are unusual in that they can ingest relatively large amounts of cardenolides without adverse physiologic effects. In experiment 1, I determined avoidance thresholds for the three cardenolides with 48 hr, two-choice tests. Mice exhibited large interspecific differences in avoidance threshold, and the interspecific ranking of the thresholds (maniculatus=leucopus >melanotis >polionotus >aztecus) was the same for each of the cardenolides. In experiment 2, I reevaluated the avoidance thresholds, but this time monitored the pattern of intake (i.e., bout lengths) during initial feeding encounters with cardenolidelaced diets. For each cardenolide, mice were subjected to three tests. In test 1, they received a control diet; in test 2, a diet containing the cardenolide at a concentration 1 log, unit below the avoidance threshold (as determined in experiment 1); and in test 3, a diet containing the cardenolide at the avoidance threshold concentration. Results were similar across all species and cardenolide types: Bout lengths in tests 1 and 2 were statistically equal, whereas those in test 3 were significantly shorter than those in test 1. The rapid rejection of cardenolide-laced diets in test 3 is consistent with a preingestive (i.e., gustatory) mechanism underlying the avoidance thresholds. I conclude (1) thatPeromyscus species differ substantially in taste sensitivity to cardenolides and that these differences may influence each species' respective ability to eat cardenolide-laced insects; and (2) that a species' relative taste sensitivity to one cardenolide predicts its sensitivity to other cardenolides. 相似文献