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991.
This paper presents the effect of open dumping of municipal solid waste (MSW) on soil characteristics in the mountainous region of Himachal Pradesh, India. The solid waste of dumpsite contains various complex characteristics with organic fractions of the highest proportions. As leachate percolates into the soil, it migrates contaminants into the soil and affects soil stability and strength. The study includes the geotechnical investigation of dump soil characteristics and its comparison with the natural soil samples taken from outside the proximity of dumpsites. The geochemical analysis of dumpsite soil samples was also carried out by scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDS). Visual inspection revealed that the MSW consists of high fraction of organics, followed by paper. The soil samples were collected from five trial pits in the dumpsites at depths of 0.5 m, 1 m and 1.5 m. Then the collected soil samples were subjected to specific gravity test, grain size analysis, Atterberg's limit test, compaction test, direct shear test, California bearing ratio (CBR) test and permeability analysis. The study indicated that the dumpsite soils from four study regions show decreasing trends in the values of maximum dry density (MDD), specific gravity, cohesion and CBR, and increasing permeability as compared to the natural soil. The results show that the geotechnical properties of the soils at all four study locations have been severely hampered due to contamination induced by open dumping of waste. 相似文献
992.
993.
Construction and Demolition Waste( C&DW) reduction management is crucial to the sustainable development of theconstruction industry. Based on the calculation of C&DW emissions in China from 2005 to 2018, the Theil index is used to calculatethe intra-regional disparities, inter-regional disparities, and overall Theil index of C&DW emissions in different regions. Theconvergence analysis of C&DW emissions in different regions is also conducted. The results show that the C&DW emissions areregionally significant, showing the overall characteristics of "the C&DW emissions in the east is higher than the west ". Moreover,the C&DW emissions in China are in a relatively stable state of development, difference in regional and overall development aresmall, with conditional β convergence across regions. The research results aim to explore the spatial difference of C&DW emissionsand provide a reference for the government to formulate regional differentiated C&DW reduction management policies. 相似文献
994.
通过扫描电子显微镜对再生粉的微观结构进行观测; 利用X射线荧光和X射线衍射,对再生粉体及制备的水泥基材料的矿物组成和水化产物进行了测定; 通过弯曲试验和单轴拉伸试验对再生粉体制备纤维增强应变硬化水泥基材料(FRCC)的力学性能进行了研究。结果表明:再生微粉以钙硅质氧化物和化合物为主,具有火山灰活性,可以增强其与基体间的二次水化反应,掺入再生粉体可有效提高FRCC的拉伸和弯曲强度; 再生粉体-FRCC弯曲韧性随着纤维掺量的增加而提高,当纤维掺量(质量分数)达到2%时,FRCC具有典型的应变硬化特征; 利用再生粉体等质量替代粉煤灰时,FRCC的极限应变有所降低,而极限荷载有较大程度提高,提高幅度均达到10%以上,且再生砂浆粉(RMP)、再生砖粉(RBP)比再生混凝土粉(RCP)制备的FRCC具有更好的应变硬化性能; 验证了在满足材料韧性要求的情况下,利用再生粉制备应变硬化水泥基材料的可行性,对再生微粉在实际工程材料中的应用提供了参考。 相似文献
995.
为了研究废机油作为再生剂的可行性以及不同再生剂对老化SBS改性沥青的再生效果,通过常规性能试验、动态剪切流变(DSR)试验对SBS改性沥青再生后的性能进行评价,采用原子力显微镜(AFM)、傅里叶红外光谱(FTIR)及热重分析(TG)研究了SBS改性沥青的再生机理.结果表明:XT-1再生剂和废机油对老化SBS改性沥青的针入度、软化点、延度均有较好的恢复效果;XT-1再生剂可以提高再生沥青的低温抗裂性能;废机油对老化SBS改性沥青疲劳寿命的影响更为明显;废机油对再生沥青黏弹性能有更好的恢复效果,可以改善老化作用对SBS改性剂的降解;XT-1再生剂和废机油的加入都调节了SBS老化沥青中的组分,改善了其路用性能,但并未发生化学反应. 相似文献
996.
997.
998.
《Ceramics International》2015,41(4):5807-5811
In this paper, porous ceramic aggregates were prepared by electrical insulators waste (EIW). Effects of sintering temperature and content of EIW on the aggregates’ properties such as bulk density, and apparent porosity, total porosity, and cold crushing strength were investigated. With increasing sintering temperature and content of EIW, bulk density and cold crushing strength of the aggregates increased, apparent porosity and total porosity decreased. Based on these results, total porosity of specimens in group B sintered at 1200 °C is 62.0%, cold crushing strength is 35.3 N, and thermal conductivity is 0.165 W/(m K) at 300 °C. Comprehensive properties of specimens can be optimized by adjusting sintering temperature. Meanwhile, strength variation resulted from the combined effects of phase transformation and matrix densification under different sintering temperatures. 相似文献
999.
《Ceramics International》2015,41(8):9455-9460
The black ceramic pigments with spinel structure have been prepared by using Cr-rich leather sludge in this paper. The washed Cr-rich leather sludge calcined at 1100 °C for 1 h as chromium oxide precursor (named as CA) was mixed with an appropriate proportion of other industrial metallic oxides, followed synthesizing black ceramic pigment by sintering. Both non-washed and washed sludge fired at 1100 °C were characterized by X-ray fluorescence (XRF) in order to determine their chemical compositions and X-ray diffraction (XRD) analysis to confirm that CA mainly contains Cr2O3 crystal phase. The results show that CA could be used as a source of chromium to prepare black pigment. The crystalline phases of obtained pigments were characterized by XRD. Furthermore, the morphology as well as the composition of pigments was investigated by scanning electron microscopy (SEM) and energy dispersion spectroscopy (EDS). The color coordinates of pigments were examined and compared with the commercial pigments based on CIE-L* a* b* values measured using UV–vis spectroscopy. The obtained pigments sintered at 1200 °C with 35–55 wt% content of CA possess the excellent black spinel structure and color effect. Under optimized conditions, the pigment has low average spectral reflectance (7%). 相似文献
1000.
为解决太原循环经济环卫产业园内生活垃圾焚烧处理处置、餐厨垃圾处理处置及其他固废处理处置过程中产生的高浓度废水处理问题,拟新建一座污水处理厂。设计处理规模为1 200 t/d,主要包括750 t/d的焚烧厂垃圾渗滤液和450 t/d的餐厨沼液。渗滤液处理采用"气浮+调节池+内循环厌氧反应器+两级A/O-MBR"的核心工艺,餐厨沼液处理采用"气浮+调节池+两级A/O-MBR"的核心工艺。污泥处理采用"离心脱水+热干化"工艺,处理后污泥含水率≤30%,干化污泥采用密封车辆送至焚烧厂焚烧处理。试运行结果表明,出水水质稳定达到设计标准。污水处理厂总投资为1.3亿元,污水处理直接成本为23.5元/t。 相似文献