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81.
介绍了马钢A/OO生物脱氮装置的工艺流程、工艺条件及影响因素,探讨了A/OO生物脱氮工艺试运行中存在的问题和解决措施。 相似文献
82.
井下矿山二次破碎裸露爆破可采用聚能药包和水封聚能药包破碎大块,聚能药包能改变药柱某个方向的猛度,提高炸药能量利用率,水封爆破利用了炸药的猛度和一部分爆力作用,从而有效地利用了炸药本身的能量,降低了爆破危害。 相似文献
83.
84.
针对2011年和2012年全国中职院校竞赛项目使用的《建筑设备给排水控制调试装置》设备,对其电气控制部分的安装调试过程进行分解。 相似文献
85.
Three-dimensional (3D) human body modeling is an important research direction in the field of clothing virtual design. On the basis of 3D human body scanning, this paper studied a method to build a 3D parametric lower body model according to body classification. The research includes three main parts. (1) Anthropometry and body shape classification. We randomly selected 333 young women ages 18–25 years old in Northeast China as the experimental sample. Then we divided the lower body shape into three categories using principal component analysis and K-means clustering. (2) Determination of feature cross sections and points, and reconstruction of feature curves. According to the average values of each body type, we obtained the mean reference body by Euclidean distance method. We determined feature cross sections and points, and extracted the 3D coordinates of the feature points of the mean reference body to reconstruct the feature curves. (3) The surface lofting and establishment of parametric 3D lower body model. According to the shape characteristics of the lower body, we constructed the guiding lines for the crotch and lower limbs, and established parametric lower body models for three body types.Relevance to industry3D human modeling is an important part of garment industry digitization. This research provides an effective way to construct a parametric 3D lower body model. The method offers a reference for the parametric virtual human modeling and virtual fitting of trousers. 相似文献
86.
87.
根据煤矿井下高压降尘系统对供水的要求,研制了一种基于PIC18F4580单片机的井下高压降尘供水系统监控装置,介绍了该装置的硬件和软件设计。该装置可实时监测水箱水位、压力、运行状态,并可将这些保护状态信息通过CAN总线接口和转换单元并入煤矿监测监控网,实现远程监测。实验结果表明,该监控装置达到了设计要求,能保证高压降尘供水系统的实时监测与安全运行。 相似文献
88.
The minimum flow requirements in the Svartå River in Sweden are directed at maintaining fishlife and providing suitable dilution for waste flows. The implications of varying the minimum flow requirements in the river are examined using a mixed integer optimisation model. The model is formulated as a modified method-of-weights technique with the economic issues of hydro-electricity generation, irrigation and urban water supply placed in the objective function and the minimum flows specified within the constraint set. The integer component of the model is required to model the operating policy at the major flow regulation facility in the system and the restricted validity of the irrigation permits. Application of the model shows that in dry years where competition between minimum flow levels and the other economic uses, is most intense, the levels achieved by the various economic objectives are only slightly reduced even with significant increases in the minimum flow requirements. Variations in minimum flow requirements of up to 45% only produce changes of 10% or less in the economic objectives. The lack of sensitivity of the objective levels is due primarily to the level of control exerted indirectly on the whole system in dry years by the release regulation policy and the restricted validity of the irrigation permits. In normal to wet years these policies are not as restrictive and more choice is available. In such years, however, there is generally sufficient water to satisfy all requirements and allocation is not a critical issue. The model itself is formulated generally so that a range of scenarios beyond those examined specifically in the paper can be considered. 相似文献
89.
A generalized equation for surface tension from the triple point to the critical point 总被引:1,自引:0,他引:1
G. R. Somayajulu 《International Journal of Thermophysics》1988,9(4):559-566
A three-parameter generalized equation is proposed for surface tension from the triple point to the critical point. This equation not only fits the data well but also is good for interpolation between the normal boiling point and the critical point. This equation is also good for extrapolation to the triple point. This equation has been tested using the surface tension of water from the triple point to the critical point. The constants of this equation obtained using orthobaric surface tensions are given for a number of compounds. The isobaric surface tensions determined at a pressure of 1 atm do not differ significantly from the orthobaric surface tensions. Such data also have been used in obtaining equations from the triple to the critical point.Nomenclature
T
c
Critical temperature, K
-
T
t
Triple point, K
-
T
m
Melting point, K
-
T
r
Reduced temperature, K
-
X
(T
c-T)/T
c
-
Surface tension, dyne · cm–1;10–3N · m–1
-
m
Surface tension at the melting point
-
f
Surface tension at T
r=0.9
-
t
Surface tension at the triple point
- Relative deviation
100[
obsd–
calcd]/
obsd
- Standard deviation
[(
obsd–
calcd)2/(No. points—No. parameters)]0.5 相似文献
90.
本文提出一种用“整体浇注法”制做三维牙——颌骨光弹性模型的新方法,即用价格便宜的石膏做阴模,先制出与真实牙几何相似的牙光弹性模型和模拟牙周膜的乳胶套,将它们粘接好,然后将其放入颌骨石膏阴模的适当位置,浇入环氧树脂混合液,用“二次固化法”进行固化,即可制成三维牙——颌骨整体光弹性模型。此法能保证模型与实物的严格几何相似和牙周的边界条件相似,使实验精度大大提高且工艺简单、成本低。 相似文献