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91.
现有级联非线性加性噪声模型可解决隐藏中间变量的因果方向推断问题,然而对于包含隐变量和级联传递因果关系的因果网络学习存在全局结构搜索、等价类无法识别等问题。设计一种面向非时序观测数据的两阶段因果结构学习算法,第一阶段根据观测数据变量间的条件独立性,构建基本的因果网络骨架,第二阶段基于级联非线性加性噪声模型,通过比较骨架中每个相邻因果对在不同因果方向假设下的边缘似然度进行因果方向推断。实验结果表明,该算法在虚拟因果结构数据集的不同隐变量数量、平均入度、结构维度、样本数量下均表现突出,且在真实因果结构数据集中的F1值相比主流因果结构学习算法平均提升了51%,具有更高的准确率和更强的鲁棒性。  相似文献   
92.
陶瓷减水剂、助磨剂、增强剂的发展现状、趋势及展望   总被引:2,自引:0,他引:2  
杨建红 《陶瓷》2005,(11):23-28,32
阐述了陶瓷行业所用添加剂的分类,以及目前国际上主要生产陶瓷添加剂的厂家及主要产品,详细介绍了陶瓷坯体减水剂、助磨剂、增强剂的种类、应用、性能特点和它们与陶瓷材料的作用机理,并对陶瓷添加剂的发展前景进行了展望。  相似文献   
93.
采用纳米铜改善二冲程油润滑性的试验研究   总被引:7,自引:0,他引:7  
居荫诚  解世文 《润滑与密封》2002,13(4):51-53,56
本文研究了加入纳米铜添加剂的润滑油在二冲程发动机标准试验程序下的润滑性。试验结果表明,纳米铜添加剂加入润滑油后,对二冲程发动机润滑性能有改善作用,并可降低发动机的摩擦损失功。  相似文献   
94.
电弧熔丝增材制造工艺由于其操作流程简便,环境开放,可生产零件范围广等优点引起了世界各国学者的极大兴趣和广泛关注。大型电弧熔丝增材设备作为此工艺实际应用的硬件基础也成为了国内外学者以及企业关注的对象。本文对大型电弧熔丝增材设备进行了简要介绍,回顾了电弧熔丝增材设备的发展历史和介绍了电弧熔丝增材设备的最新研究进展。此外,本文还对大型电弧熔丝增材设备的未来发展方向进行了展望。  相似文献   
95.
钱殿存  马文英 《油田化学》1993,10(4):351-353
腈纶废料的水解、氧化降解产物(XD9101)可用作钻井液降粘剂。本文探讨了XD9101的制备工艺条件及其在钻井液中的性能。XD9101在钻井液中具有良好的降粘效果和较强的抗温抗盐能力。  相似文献   
96.
This study mainly evaluates the elastic modulus of 316 stainless steel lattice structures fabricated via binder jetting process. In this present research, both solid and lattice samples are designed and fabricated by binder jetting process for two different types of mechanical tests. Besides experimental study, a numerical model based on energy approach has been proposed to predict the effective elastic modulus of fabricated lattice samples. By comparing the calculated results of the proposed numerical model with the experimental results, the established model is proved to be validated. This numerical model can be used to determine the parameters of lattice structures fabricated by binder jetting process for desired mechanical properties. At the end, both advantages and disadvantages of the lattice structures fabricated by binder jetting process are analysed. Based on this analysis, the potential application and future research work are pointed out.  相似文献   
97.
This is a theoretical work for the characterization of homogeneous chemical reactions coupled to a reversible electrode process and analyzed by Additive Differential Pulse Voltammetry at spherical electrodes or microelectrodes. Explicit analytical expressions are presented for the CE and EC mechanisms valid for spherical electrodes of any radius and fast chemical reactions. These enable us to easily and rapidly analyze the response of these mechanisms even under very strong kinetic conditions.The ADPV technique proves to be very useful in the identification of the reaction mechanism and the characterization of the coupled chemical reaction by means of the values of the peak currents and potentials and the crossing potential, which can be measured with good accuracy from several ADPV experiments with different pulse heights. Simple criteria are given for discrimination between different situations where the electrode process is coupled to a homogeneous chemical reaction and, what is more difficult, to distinguish between an EC mechanism and an irreversible charge transfer process. Moreover, direct procedures for quantitative determination of kinetic and thermodynamic information are established.  相似文献   
98.
The influence of alkylpyridines additive to an I/I3 redox electrolyte in acetonitrile on the performance of a bis(tetrabutylammonium)cis-bis(thiocyanato)bis(2,2′-bipyridine-4-carboxylic acid, 4′-carboxylate)ruthenium(II) dye-sensitized TiO2 solar cell was studied. IV measurements were performed using more than 30 different alkylpyridines. The alkylpyridine additives showed a significant influence on the performance of the cell. All the additives decreased the short-circuit photocurrent (Jsc), but most of the alkylpyridines increased the open-circuit photovoltage (Voc) and fill factor (ff) of the solar cell. The results of the molecular orbital calculations suggest that the dipole moment of the alkylpyridine molecules correlate with the Jsc of the cell. These results also suggest that both the size and ionization energy of pyridines correlate with the Voc of the cell. Under AM 1.5 (100 mW/cm2), the highest solar energy conversion efficiency (η) of 7.6% was achieved by using 2-propylpyridine as an additive, which was more effective than the previously reported additive, 4-t-butylpyridine.  相似文献   
99.
综述了近年来国内外粘附性颗粒添加组份流态化的进展,并对粘附性颗粒流化床中颗粒受力分析及模型进行了评价.指出了粘附性颗粒添加组份流态化存在的问题及发展方向,提出应开展添加组份的性质、种类、添加比例及其与粘附性颗粒之间相互作用的机理研究.  相似文献   
100.
In this paper, the influence of some additives on the rheological and technological properties of crumb rubber modified binders has been studied. The research has been mainly focused on the degree of bitumen modification, measured as the improvement of the mechanical properties, produced by the additives used, and the storage stability of these binders at high temperature. The experimental results obtained reveal that all the polymeric additives used yield an improvement in both rheological and technological properties of the binder. The storage instability of these binders has been associated to sedimentation processes of insoluble CR particles that strongly influence the mechanical properties of the binder. The additives and processing conditions selected in this study do not completely prevent problems associated with the poor stability of CRMBs during storage at high temperature. Nevertheless, the use of polyoctenamer, FT-wax or SBS-containing additives improves CRMB stability. In this sense, similar loss tangent values were found before and after hot storage of these binders.  相似文献   
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