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排序方式: 共有1449条查询结果,搜索用时 15 毫秒
41.
Wei Wang Yingzi Ren Bin Han Tan Ren Gewei Liu Yujian Liang 《The Structural Design of Tall and Special Buildings》2019,28(1)
In this paper, composite shear walls with different encased steel plates (flat, horizontal corrugated, and vertical corrugated) were tested and simulated by Abaqus to investigate the seismic behavior of corrugated steel plate concrete composite shear walls (SPCSWs). The failure characteristics, deformation and energy dissipation capacity, and stiffness and bearing capacity of the structures under low‐frequency cyclic load were analyzed, and indexes of the seismic performance were obtained. The formulas of the shear‐bearing capacity of steel plate concrete composite shear walls are suggested, and the shear‐sharing ratio of each member is obtained. According to the obtained results, corrugated steel plates can bond with concrete well, and the bearing capacity of the vertical corrugated SPCSW are higher than that of the horizontal corrugated SPCSW. Compared with flat SPCSW, corrugated SPCSW has higher initial stiffness and lateral stiffness, better ductility and energy dissipation ability, and the degradation of bearing capacity and stiffness is slower. The shear‐sharing ratio of a steel plate is larger than that of reinforced concrete in the flat SPCSW and the vertical corrugated SPCSW, the shear force shared by steel plate and reinforced concrete in horizontal corrugated SPCSW is basically the same. 相似文献
42.
基于LabVIEW的数据处理方法 总被引:12,自引:8,他引:4
数据处理是各种工程测试和实验过程中的重要环节,数据处理的理论及方法是否正确将直接影响测试工作的效率和结论的准确性。文中介绍了用DDE实现LabVIEW与Excel的通信,并利用LabVIEW与Excel的通信功能从Excel中读取测试数据,然后进行滤波处理并直接计算出测试数据的特征值。为处理采集到的数据提供了一种新的方法,该方法简化了数据分析过程,提高了测试的效率。 相似文献
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该文考察了米曲霉和黑曲霉在单独制曲及混合制曲条件下,成曲的中性蛋白酶、酸性蛋白酶、糖化酶及孢子数,探讨了酱油多菌种制曲的可行性.实验以豆粕、麸皮为原料,以AS3.042米曲霉、AS3.350黑曲霉为菌种,探讨了2种制曲方式及不同配比制曲效果的影响.结果表明,米、黑曲霉分开制曲比混合接种制曲所得成曲效果好,米、黑曲霉分别以33℃制曲42h、48h得成品曲,再以2∶1混合所得成曲可获得较佳的酶活力,曲料总蛋白酶活力2748U/g与对照值相当,而酸性蛋白酶及糖化酶活力分别达712U/g、1090U/g,较对照分别提高55.8%、25.4%. 相似文献
46.
研究引入了色率、黄色指数、红色指数、玫瑰紫指数的概念,建立了对玫瑰醋色泽进行量化评价的方法。即将食醋稀释50%后,5000r/min离心30min,取上清液分别测其在波长460nm、510nm、530nm、610nm处的吸光度值,分别用10×lg(OD460nm/OD610nm)、10×lg(OD510nm/OD610nm)、10×lg(OD530nm/OD610nm)、OD610nm×20000/0.076来表示食醋的黄色指数、红色指数、玫瑰醋紫指数和色率,并用这种方法评价了保温后熟及保藏条件对食醋色泽的影响。通过试验发现在试验设计的保温时间范围内,色率随保温时间的增加呈下降趋势;黄色指数、红色指数、玫瑰紫指数随着保温时间缓慢增大;常温保藏比4℃保藏样品的色率更高,而黄色指数、红色指数、玫瑰紫指数则是4℃保藏样品比常温保藏的高。 相似文献
47.
Ying Xue Zhonghan Sheng Hong Zhao Zhijiao Wu Xiangjun Li Yujian He Zhuobin Yuan 《Electrochimica acta》2012
A novel copolymer based on 2-aminothiazole (AT) and 2-amino-4-thiazoleacetic acid (ATA) is electrochemically synthesized and then characterized using UV–visible absorption spectroscopy (UV–vis), Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM) and electrochemical techniques. The results confirmed that the obtained polymer was a copolymer rather than a blend or a composite of the respective homopolymers and could improve the electrochemical response of both positively and negatively charged analytes. Therefore, the copolythiazole film was applied to determine ascorbic acid (AA), dopamine (DA) and uric acid (UA). It is found that the peak separating degrees and peak currents of AA, DA and UA at copolythiazole modified electrode were much better than those at bare GCE. Under the optimum conditions, the linear calibration curves were obtained in the range of 10–2000 μM for AA, 1–150 μM for DA, 1–180 μM for UA. The detection limits of AA, DA and UA were 2, 0.04 and 0.4 μM, respectively (S/N = 3). The practical application of the modified electrode was demonstrated by the determination of UA in urine sample. 相似文献
48.
Ariel Cohen Peishan Liu-Synder Dan Storey Thomas J. Webster 《Nanoscale research letters》2007,2(8):385-390
Bioactive coatings are in high demand to control cellular functions for numerous medical devices. The objective of this in vitro
study was to characterize for the first time fibroblast (fibrous scar tissue forming cells) adhesion and proliferation on
an important polymeric biomaterial (silicone) coated with titanium using a novel ionic plasma deposition (IPD) process. Fibroblasts
are one of the first anchorage-dependent cells to arrive at an implant surface during the wound healing process. Persistent
excessive functions of fibroblasts have been linked to detrimental fibrous tissue formation which may cause implant failure.
The IPD process creates a surface-engineered nanostructure (with features usually below 100 nm) by first using a vacuum to
remove all contaminants, then guiding charged metallic ions or plasma to the surface of a medical device at ambient temperature.
Results demonstrated that compared to currently used titanium and uncoated silicone, silicone coated with titanium using IPD
significantly decreased fibroblast adhesion and proliferation. Results also showed competitively increased osteoblast (bone-forming
cells) over fibroblast adhesion on silicone coated with titanium; in contrast, osteoblast adhesion was not competitively increased
over fibroblast adhesion on uncoated silicone or titanium controls. In this manner, this study strongly suggests that IPD
should be further studied for biomaterial applications in which fibrous tissue encapsulation is undesirable (such as for orthopedic
implants, cardiovascular components, etc.). 相似文献
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目的 解决传统机器视觉机器人抓取系统对多目标及复杂目标背景分割不精确导致的目标定位精度差而影响机器人抓取效率的问题,提出一种新的深度学习抓取识别定位系统。方法 搭建由Delta机械臂、PC上位机、双目相机等组成的硬件系统,对工业部署常用的YOLO系列算法进行对比研究。将YOLO与U-NET相结合,用于目标的检测和分割。在精确分割出属于目标和背景目标的像素区域的同时,计算边缘和中心位置信息,运用立体视觉技术得到三维位置,并转换为世界坐标系,由PC机引导机械臂去完成抓取任务。结果 深度学习目标检测和图像分割相结合的系统在较复杂背景、多目标的场景下比未添加图像分割的算法拥有更好的目标定位精确度。结论 YOLOv5和U-NET相结合的目标定位抓取方法具有较高的鲁棒性,达到了并联机械臂的抓取要求。该方法能够运用于其他多自由度机械臂上,具有良好的应用价值。 相似文献