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21.
提供了一种简单而有效的利用计算机辅助进行塔板布置的方法。给出了相应的计算内容和程序。有较好的通用性。适用于浮阀塔板和筛孔塔板。 相似文献
22.
淋降式穿流角钢塔板由于结构简单、防堵效果好、压降低,已在国内40余座塔中得到成功应用。本文主要介绍了该塔板的基本结构、压降估算、塔内排列新方案以及应用实例。 相似文献
23.
A self-adhesive insulator is a component of a home appliance that is used to suppress vibration or prevent humidity affecting the internal parts of the appliance. There is a wide range of types and designs available, allowing them to be applied to areas having different shapes. At the design stage, once an insulator design has been developed sufficiently to identify its dimensions and features, the attaching time and baseline cost must be estimated with reasonable accuracy to enable a comparison of vendor quotes. However, the current estimation method is not sufficiently accurate in terms of the baseline cost. This paper presents a motion-based time-estimating scheme with which the time required for the attachment of such insulators can be calculated more accurately. The scheme has been developed by analyzing the motions needed to attach 350 insulators and then designating representative motions and their time values. For this purpose, a modular arrangement of predetermined time standards (MODAPTS) is adopted. Motion-based time-estimation method is useful in terms of simplicity and accuracy. It enables design engineers to estimate the time required for the attachment based only on a drawing of the insulator and a few MODAPTS rules. Estimates made with this method should vary from the actual value by no more than 9.5%. 相似文献
24.
On the Predominant Electron-Donicity of Polar Solid Surfaces 总被引:2,自引:0,他引:2
The reasons for the predominant electron-donicity of almost all solid polar surfaces and its implications are discussed in this paper. By contact angle or interfacial tension measurements, the electron-accepting as well as the electron-donating properties of polar liquids can be ascertained, through the interplay between their energies of adhesion and cohesion. For the solid-liquid interface, direct interfacial tension measurements are not possible, but indirectly, solid/liquid interfacial tensions of polar systems can be obtained by contact angle measurement. However, as the energy of cohesion of a solid does not influence the contact angle formed by a liquid drop placed upon its surface, one can only measure the solid surface'ks residual polar property, manifested by the energy of adhesion between solid and liquid. This residual polar property is of necessity the dominant component; in most cases this turns out to be its electron donicity. When, by means of contact angle measurements with polar liquids, both electron-accepting and electron-donating potentials are found on a polar solid, it is most likely still partly covered with a polar liquid: usually water. The amount of residual water of hydration of a polar solid follows from its polar (Lewis acid-base) surface tension component (γAB). The degree of orientation of the residual water of hydration on a polar solid can be expressed by the ratio of the electron-donating to electron-accepting potentials (γ⊖/γ⊕), measured on the hydrated surface. 相似文献
25.
通过厂房地下洞室群围岩点荷载试验,获得了洞室不同深度位置岩石点荷载强度值,试验发现各平洞点荷载强度随洞室深度变化呈现明显的波动性变化特征。研究表明,围岩岩性、断层以及岩石微观结构等是影响岩石点荷载强度的主要因素。其中,围岩中普遍发育的矿物定向排列是导致点荷载强度波动性变化的最主要因素。最后,通过与实测单轴抗压强度比较,得出当岩石单轴抗压强度大于60 MPa时,宜采用成都理工大学推荐公式换算单轴抗压强度,当单轴抗压强度小于60 MPa时,宜采用水利水电规范推荐的转换公式计算岩石单轴抗压强度。 相似文献
26.
为探究植被的排列方式及坡度大小对坡面流弗劳德数Fr的影响,以期揭示坡面流弗劳德数Fr的内在规律。利用人工模拟试验,系统研究了6个坡度、3种植物排列方向与水流方向呈不同走向角的条件下Fr与单位底面积的空间摩阻表面积K值的特征关系。表明在非淹没状态下,Fr与K值的关系为随K值的增大Fr呈现先减小后趋于平稳的趋势;Fr的取值随坡度的增大而增大;在一定的坡度范围内,同一坡度下,当Fr1时,同一K值下,走向角越大对应的Fr值越小,当Fr1时则相反;同一走向角下,在同一K值下,坡度越大对应的Fr就越大。得出在坡度一定的条件下,坡面植被的排列方式不同,弗劳德数Fr的取值也不相同;坡度是影响Fr取值范围的重要因素之一。 相似文献
27.
重钙装置改产磷铵后,造粒机内的物料行为发生了变化,即“料浆涂布-水分蒸发-氨化反应”这一物理化学过程。喷氨孔与水平线的夹角是影响这一过程的重要因素,本文对夹角的确定进行了理论分析。在实验基础上,对造粒机预中和料浆喷头位置、氨分布管的长度和角度进行了重新配置。生产表明,重新配置的造粒机内部构件具有很好的造粒效果。 相似文献
28.
针对VB 6.0编程软件界面不够美观,需要使用第三方皮肤系统进行界面美化,以及Skinsharp等高效的皮肤控件对MDI窗体的支持不够稳定,经常出现移动窗体后无法对窗体重新排列的问题,提出了模拟VB对MDI窗体的排列效果,实现与VB类似的MDI窗体平铺算法,实现了层叠、水平和垂直三种排列效果,并在此基础上增加了弹性层叠功能和固定窗体次序功能。所用方法解决了加载皮肤后子窗体无法排列的问题。结果表明:所用算法的执行效率不高,只有VB方法的二分之一,特别是加上皮肤后层叠的效率下降较多;但当窗体数量较少时,所用算法具有一定实用性,可以作为加载皮肤系统时VB默认排列的替代方法。 相似文献
29.
30.
A series of organic-soluble naphthalocyanine derivatives (YmMNcX4) have been synthesized. Their spectroscopic properties in organic solutions and in thin films were studied. MNcX4 such as MNc(t-Bu)4 (5a-5c) and MNc(On-Bu)4 (5j) formed H-aggregates even in dilute solutions. MNc(CO2R')4 (5d-5i) had much stronger H-aggregation properties compared with those ofMNc(t-Bu)4 and MNc(On-Bu)4. Especially, MNc(CO2R')7 complexes (M=Cu, Pd and Ni) existed exclusively without monomers in the aggregated state even in highly dilute solutions. MNcX4, which has strong H-aggregation properties, showed merely H- aggregate absorption maxima in thin films. In contrast, Y2MNcX4 (4), which has sterically hindered Y groups, showed monomerically pure characteristics in solution. However, thin films of Y2MNcX4 have a J-type molecular arrangement, exhibiting a red shift of Q-band absorption. The monomeric properties of Y2MNcX4 in solutions and J-type molecular arrangement in thin films arise from steric hindrance of two Y groups, such as R3SiO-in Y2MNcX4, which prevents strong H-aggregation of naphthalocyanine. 相似文献