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61.
Chia (Salvia hispanica) is an ancient crop that has experienced an agricultural resurgence in recent decades owing to the high omega 3 fatty acid (ω-3) content of the seeds and good production potential. Analysis of 563 lots of chia grown in Kentucky and 10 lots from Arizona, Australia, Mexico, and Peru was performed. All of these lots were assessed for fatty acid, oil, and protein content, while a subset of 120 samples were assessed for amino acids, fiber, minerals, and trace elements. The mean oil content was 31.3%, ranging from 21.4% to 35.3%. The protein content averaged 22.8%, ranging from 18.2% to 28.2%, and the ω-3 FA α-linolenic acid (ALA) averaged 61.3%, ranging from 33.9% to 69.9%. Using these seed lots, nondestructive near-infrared spectroscopy (NIRS) calibrations were developed for whole and ground seed oil, protein, moisture, and the six major fatty acids. The R2 and SE of cross-validation (SECV) values for oil were 0.78 and 0.95, respectively, while those for protein were 0.75 and 1.05, respectively. The NIRS calibrations for fatty acid had R2 and SECV greater than 0.6 and less than 10% of actual values for all major fatty acids, respectively. An R2 of 0.99 was established for moisture content of whole seeds within the range of 3–10% moisture content. The precision and accuracy of these calibrations is adequate for use by breeders, growers, and food quality experts to quantitatively assess these major constituents without the need for costly and time-consuming chemical analysis.  相似文献   
62.
李华 《陕西煤炭》2020,39(2):132-134,124
神东公司大多数综采工作面在使用华宁KTC101控制系统,以实现对运输设备的集中控制。首先介绍了华宁KTC101控制系统在神东公司综采工作面的设备组成和各部分的作用及运行方式,并阐述了该系统在综采工作面的布局和运输设备的参数设置。通过对其控制原理和实际工作时常用方式的分析,总结了一些常见的控制器、接触器、扩音电话故障处理方法,可以使操作人员更加熟悉设备性能,极大提高设备自动化程度。  相似文献   
63.
随着超大规模集成电路的发展,器件特征尺寸不断缩小,必然会出现Cu互连扩散阻挡层厚度无法进一步减小等瓶颈问题。因此,开发新型无扩散阻挡层Cu合金薄膜(Cu种籽层)势在必行。该新型互连结构在长时间的中高温(400~500℃)后续工艺实施过程中,需同时具备高的稳定性(不发生互扩散反应)和低的电阻率。基于此,首先综述了目前无扩散阻挡层结构的研究现状及问题,然后对基于稳定固溶体团簇模型设计制备的无扩散阻挡Cu-Ni-M薄膜的研究工作进行了梳理,通过多系列薄膜微观结构、电阻率及稳定性的对比,深入探讨了第三组元M的选择原则及其对薄膜热稳定性的影响。为进一步验证稳定固溶体团簇模型的有效性,对第二组元的变化进行了相关讨论。结果证实,选取原子半径略大于Cu、难扩散且难溶的元素作为第三组元M,薄膜表现出良好的扩散阻挡能力;当M/Ni=1/12,即合金元素完全以团簇形式固溶于Cu基体时,薄膜综合性能达到最优,能够满足微电子行业的要求。所有研究表明,稳定固溶体团簇模型在无扩散阻挡层Cu合金薄膜的成分设计方面十分有效,该模型也有望在耐高温Cu合金及抗辐照材料成分设计方面推广使用。  相似文献   
64.
The two-dimensional infiltration experiment was carried out by means of digital image technology. The evolution process of the wetting body was described. The wetted front distance and the time show a very significant power function relationship. The horizontal wetted distance is larger than the vertical wetted distance in the initial stage. Then, the vertical distance of the wetted body gradually approaches to the horizontal distance. The infiltration distance decreases as the content of fine particles increases. The wetted front migration rate curve shows a three-stage change law, and it increases with the increase of coarse particle content. The directional velocity ratio is defined. The initial value of horizontal infiltration rate is larger than that of vertical one, and then the vertical infiltration rate is gradually close to the horizontal value. The empirical relationship between the characteristic particle size and the stable infiltration rate is established, which provides a theoretical basis for the prediction of the stable infiltration rate in in-situ leaching.  相似文献   
65.
Appropriate temperature range and distribution is necessary for Li-ion battery module, especially in real application of electric vehicles and other energy storage devices. In this study, a comprehensive design of liquid cooling–based thermal management system for a Li-ion battery module's fast discharging process is investigated, and thermal analysis and numerical computation are conducted. The effects of different flow directions, different shapes of the liquid channels, different widths of channels, different thicknesses of cold plate, and the comparison between uniform and nonuniform channels' distribution are analyzed. Simulation results indicate that the liquid cooling system provides acceptable cooling performance in preventing heat runaway of the battery module under 5C discharging current rate. A five-channel cooling plate can reduce the maximum temperature with appropriate design. Additionally, specific flow direction mini-channels, different shapes of the liquid-channels, and nonuniform channels are designed to compare the maximum temperature and uniformity of temperature distribution in the module. Maximum temperature can be improved through the increase of channel width and thickness of the cooling plate. The original design is proved to be the best design considering the maximum temperature, maximum temperature deviation, and final temperature standard deviation of the fast discharging process.  相似文献   
66.
采用脉冲电沉积技术在304不锈钢表面制备Ni-Cu合金镀层,镀液组成和工艺条件为:NiSO4ꞏ6H2O 200g/L,CuSO4ꞏ5H2O 10 g/L,十二烷基硫酸钠0.2 g/L,柠檬酸钠80 g/L,糖精0.2 g/L,pH 4.0,温度25°C,搅拌速率30 r/min,平均电流密度40~120 mA/cm2,脉冲频率0~100 Hz,占空比20%~90%,时间30 min。研究了平均电流密度、脉冲频率和占空比对Ni-Cu合金镀层的元素组成、表面形貌和显微硬度的影响,得到较优的工艺参数为:平均电流密度40 mA/cm2,脉冲频率50 Hz,占空比60%。该条件下所得Ni-Cu合金镀层由质量分数分别为56.53%和43.47%的Ni和Cu组成,呈“菜花”状形貌,结晶细致、均匀,显微硬度为614.4 HV。  相似文献   
67.
Low-permittivity Ca1−xSrxSnSiO5 (0 ≤ x ≤ 0.45) microwave dielectric ceramics were prepared via traditional state-reaction at 1400°C-1450°C for 5 hours. Moreover the microwave dielectric properties of SnO2 ceramic were obtained for the first time. SnO2 ceramic was difficult to densify, and SnO2 ceramic (ρrel = 65.1%) that was sintered at 1525°C exhibited the optimal microwave dielectric properties of εr = 5.27, Q × f = 89 300 GHz (at 14.5 GHz), and τf = −26.7 ppm/°C. For Ca1−xSrxSnSiO5 (0 ≤ x ≤ 0.15) ceramics, Sr2+ could be dissolved in the Ca2+ site of Ca1−xSrxSnSiO5 to form a single phase, and the partial substitution of Ca2+ by Sr2+ could improve the microwave dielectric properties of CaSnSiO5 ceramic. Secondary phases (SnO2 and SrSiO3) appeared at 0.2 ≤ x ≤ 0.45 and could adjust the abnormally positive τf value of CaSnSiO5 ceramic. The highest Q × f value (60 100 GHz at 10.4 GHz) and optimal microwave dielectric properties (εr = 9.42, Q × f = 47 500 GHz at 12.4 GHz, and τf = −1.2 ppm/°C) of Ca1−xSrxSnSiO5 ceramics were obtained at x = 0.05 and 0.45, respectively.  相似文献   
68.
An optimized solar dish collector (OPSDC) system was proposed in our previous work, which can achieve excellent the optical efficiency and flux uniformity under ideal optics. On this basis, the impacts of the non-ideal optical factors on the optical performance of OPSDC system with a cylindrical and conical receiver are studied in detail and compared with the conventional solar dish collector (COSDC) system in this paper. Where the non-ideal optical factors considered are relatively comprehensive, including the mirror slope error, tracking error, installation error of the mirror and receiver, and receiver's absorptivity degeneration. An optical model with the non-ideal optical factors is built in detail by the ray tracing method, and the corresponding ray tracing codes are developed and verified by literatures and optical software OptisWorks 2012. The results show that the OPSDC system not only has a significantly smaller peak local concentration ratio (LCR) and non-uniformity factor than the COSDC system under the same non-ideal optical factor, but also has excellent optical performance. This means that OPSDC system can effectively avoid the heat absorber generating high-temperature hot spots, thus significantly improving its working reliability and service lifetime. In addition, the tracking error, installation error of the receiver and mirror all lead to the increase of the peak LCR and non-uniform factor, while the mirror slope error and absorber's absorptivity degeneration are conducive to reducing the peak LCR and non-uniform factor. This work can provide a reference for error control of COSDC system and OPSDC system in manufacturing, installation and operation.  相似文献   
69.
Here, phase transformation and electrochemical characteristics of non-stoichiometry La4MgNix (x = 16, 17 and 18) hydrogen storage alloys were studied. It is found that after annealed at 1223 K for 24 h, the minor AB3 and AB5 phases in La4MgNi16 alloy transform into A2B7 phase by a peritectic reaction and the La4MgNi16 alloy shows a A2B7 single phase structure. Double phase structures of A2B7/A5B19 are obtained in La4MgNi17 and La4MgNi18 alloys after annealed at the same condition. The abundance of A5B19 phase increases as x increases, indicating the increasing x value contributes to the formation of A5B19 phases. Electrochemical studies show that the maximum discharge capacity and capacity retention at the 100th charge/discharge cycles (S100) of A2B7 single phase La4MgNi16 alloy is 373 mAh g−1 and 78.4%, respectively. The appearance of A5B19 (minor) phase in the La4MgNi17 alloy makes a remarkable improvement in the discharge capacity from 373 mAh g−1 to 388.8 mAh g−1, as well as the S100 from 78.4% to 90.1%. It is believed that the LaMgNi-based alloy with the A2B7(main)/A5B19(minor) phase structure possesses the good overall electrochemical properties and is applicable to the high-power and long-cycle life negative electrode material for nickel metal hydride batteries.  相似文献   
70.
基于CPFD(Computational particle fluid dynamics)方法,对实验室前期研究的催化裂化管式分配器内的颗粒分配特性及内部流动特性进行了数值模拟,系统研究了输送风、松动风及分配器倾斜角度对颗粒分配不均匀指数的影响,并进一步考察了输送风和松动风对分配器各出口气体流量分布及内部气 固流动特性的影响。结果表明,增大输送风量、松动风量以及分配器的倾斜角度均可以降低颗粒分配不均匀指数,但改变松动风量的效果不如改变输送风量和倾斜角度显著。分配器倾斜角存在一个最优值时,颗粒分配均匀性最佳。输送风的增大会使得颗粒出料量最高的排料口的位置逐渐向分配器的末端移动,中间排料口所流出的气体流量占比增大,末端排料口排风量占比减小。引入松动风后,各出口的颗粒排料量更加接近,同时靠近末端排料口的气体流量占比明显增大。  相似文献   
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