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31.
In this study, two types of convolutional neural network (CNN) classifiers are designed to handle the problem of classifying black plastic wastes. In particular, the black plastic wastes have the property of absorbing laser light coming from spectrometer. Therefore, the classification of black plastic wastes remains still a challenging problem compared to classifying other colored plastic wastes using existing spectroscopy (i.e., NIR). When it comes the classification problem of black plastic wastes, effective classification techniques by the laser spectroscopy of Fourier Transform-Infrared Radiation (FT-IR) with Attenuated Total Reflectance (ATR) and Raman to analyze the classification problem of black plastic wastes are introduced. Due to the strong ability of extracting spatial features and remarkable performance in image classification, 1D and 2D CNN through data features are designed as classifiers. The technique of chemical peak points selection is considered to reduce data redundancy. Furthermore, through the selection of data features based on the extracted 1D data with peak points is introduced. Experimental results demonstrate that 2DCNN classifier designed with the help of 2D data feature selection as well as 1DCNN classifier shows the best performance compared with other reported methods for classifying black plastic wastes.  相似文献   
32.
为提高聚碳酸酯(PC)材料流动性,以乙二醇(EG)为溶剂降解废弃聚对苯二甲酸乙二醇酯(PET)得到的产物为改性剂,制备PET降解产物改性的PC复合材料,对测试结果进行分析讨论。结果表明,PET降解反应中产物主要BHET及其低聚物,降解产物的加入能够有效提高复合材料熔体质量流动速率,且熔体质量流动速率随着降解产物添加量的增加而增大.综合分析复合材料的力学性能及流动性,确定最佳实验用量为4%,降解体系为m(PET)∶m(EG)为1∶3.   相似文献   
33.
以高密度聚乙烯(HDPE)和低密度聚乙烯(LDPE)共混废塑料为原材料,在不同温度下裂解得到的2种裂解蜡WMa-1和WMa-2,采用该裂解蜡对70~#基质沥青进行改性,探讨聚乙烯废塑料裂解蜡作为沥青温拌添加剂的可行性。试验结果表明,在试验掺量范围内,WMa-1和WMa-2均具有良好的降黏效果,WMa-1能提高沥青的高温性能和抗车辙性能,但对沥青的低温性能不利;WMa-2能显著降低沥青硬度,改善沥青的低温塑性,但使沥青的高温抗变形能力明显降低。  相似文献   
34.
对聚乙烯丙纶复合防水卷材产品及应用体系的特色、构成及配套胶粘剂作了深入探讨,并对该类材料的发展定位提出了看法.  相似文献   
35.
李守田 《山西建筑》2002,28(2):71-72
介绍了某住宅楼采用FSG憎水性膨胀珍珠岩作保温层,氯化聚乙烯-共混作防水层的防水施工技术,同时还提出了在混凝土墙面无泛水槽部位,出屋面管道及排气管道采用辅助防水的措施;指出了作屋面也水时由中间向四周,电梯房屋顶由三边向中间铺贴以有排气孔留到屋顶中间等的注意事项。  相似文献   
36.
介绍了武汉阳逻电厂三期扩建工程屋面防水保温的施工工艺、施工注意事项和所采取的防水工程质量措施等。  相似文献   
37.
Viral hepatitis type A is the most prevalent waterborne disease in U.S.A. and the number of cases has been increasing in recent years (Melnick et al., 1978). Till now, few works were performed on Hepatitis A Virus (HAV) concentration in water (Hejkal et al., 1982, Elkana et al., 1983). In this paper the filter adsorption-elution method, widely used with other viruses (Wallis and Melnick, 1967; Fields et Metcalf, 1975; Smith and Gerba, 1982), was selected to concentrate HAV from experimentally-contaminated distilled water. Filtration was performed through two cellulose membranes (RAWP 04700 and HAWP 04700 Millipore). Eluate or filtrate viruses were precipitated by polyethylene glycol 6000. HAV is detected by solid phase radioimmunoassay according to a previously described method (Deloince et al., 1982). Figure 1 shows the results of adsorbing HAV at different pH levels. Analysis of variance pointed out that, for the pH levels between 3 and 4, the differences were not significant (P = 0.05). Table 1 shows the effects of pH and number of passages of 3% beef extract or 0.2 M glycin buffer on HAV elution. For both eluents the differences in function of pH levels and number of passages of eluent through the membrane were not significant (variance analysis P = 0.05). On the other hand, the comparison between the two eluents pointed out the higher efficiency of beef extract (t-test, P = 0.001). After this procedure, HAV replication occurred in human hepatocarcinoma cells PLC/PRF/5 (Fig. 2) inoculated according to a previously described method (Crance et al., 1983). As poliovirus (Sobsey et al., 1973), HAV adsorption is the most efficient at acid pH levels. Between pH 4.5 and 5, the remarkable adsorption decrease might be related to the inversion of the HAV electrostatic charges sign, i.e. to the occurrence of an isoelectric point. The HAV elution is different from the poliovirus one, the efficiency of which increased with pH (Wallis et al., 1972) and eluent passage numbers (Farrah et al., 1976). That might suggest that from pH 7.5, both the HAV particles and membranes have negative charges which give enough repulsive forces to allow a good elution efficiency. Improvement of HAV elution efficiency by beef extract is similar to a result obtained with poliovirus by Landry et al. (1978). This effect might be explained by the proteinous material presence in beef extract. HAV replication in cell cultures shows the biological properties preservation after this procedure.  相似文献   
38.
燃气用聚乙烯管道的应用   总被引:1,自引:1,他引:1  
介绍了聚乙烯燃气管道在国内外的发展与应用历程,分析了聚乙烯燃气管道在设计、施工、运行中应注意的问题。  相似文献   
39.
对复合材料要求增强纤维表面具有良好黏合力. 针对这一情况,详细综述了提高超高分子质量聚乙烯纤维表面润湿性的各种改性技术的发展状况,并对各种方法的作用机理、影响因素和工业化实施的可行性进行了比较;同时介绍了改性纤维的性能表征方法.  相似文献   
40.
To further understand the long-term effect of rejuvenation fluid on water tree aged cross-linked polyethylene (XLPE) cables after silicone injection, electrical performance and microstructure of water tree aged cables were investigated during an electrical-thermal accelerated aging experiment. Two groups of treated and untreated water tree aged cable samples were subjected to electrical-thermal aging for 2 weeks. The results of the dielectric loss factor showed that the electrical performance of the treated samples was significantly better than that of untreated samples after electrical-thermal aging. Microobservation results showed that the overall water tree sizes of the treated samples were much smaller than those of the untreated samples after electrical-thermal aging. Furthermore, there was a second growth of water trees in the original water tree region during electrical-thermal aging in both groups of samples. Using scanning electron microscopy (SEM) and energy-dispersive spectroscopy (EDS), rejuvenation fillers were observed tightly embedded in water tree voids after electrical-thermal aging. The infrared (IR) spectroscopy analysis results showed that the concentration of rejuvenation fluid increased from the outer layer to the inner layer of insulation. Based on the results, due to the improvement of the electric field at the water tree tip and the diffusion of silicone fluid in the insulation layer, both the second growth in the original water tree region and continuing growth at the water tree tip can be effectively inhibited.  相似文献   
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