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951.
分析了传统 36 0 0造气工艺流程存在的缺点 ,针对邯钢集团化肥公司的实际情况并配合 12 2 0工程的顺利实施 ,决定采用设备紧凑、发气量大、工艺设备较先进的 36 0 0煤气发生炉系统。在该系统的设计中 ,除了采用新型高效旋风除尘器和联合热管锅炉回收器外 ,还充分吸收了近年来我国造气技术涌现出来的先进技术装备 相似文献
952.
逆凝聚包覆法制备硫黄调节型粉末氯丁橡胶 Ⅰ.粒径分布 总被引:2,自引:3,他引:2
采用逆凝聚包覆法制备硫黄调节型粉末氯丁橡胶(PCR)并考察加料方式、搅拌转速和胶乳加人流速对产物粒径分布的影响。建立氯丁胶乳的逆凝聚粉末化模型并采用均匀试验设计的方法对该模型进行了验证。验证结果表明,该模型可以有效地模拟PCR的逆凝聚包覆氯丁胶乳的粉末化过程。PCR产物中粒径1~3mm的中等粒子的质量分数仅与搅拌转速有关,表明湍流爆裂是产生中等粒子的主要原因,而带状拉伸则是产生较粗颗粒和细小粒子的主要原因。扫描电子显微镜观察发现,采用逆凝聚包覆法制备的PCR粒子为单颗连续粒子,即产物粒子由单颗胶乳液滴凝聚而成。 相似文献
953.
用膨化硝酸铵、硫磺、木粉和柴油作原材料,通过建立工业炸药配方设计及最优化数学模型,得到新型膨化硝胺硫横工业炸药配方。通过几种工业炸药的理论参数和实际爆炸性能的比较,得出新型膨化硝铵硫磺工业炸药具有低的成本和优良的爆炸性能。 相似文献
954.
污泥沉积池罩是污泥沉积池的重要部件.由于其跨度大,长期处于酸性环境中,对材料的强度和防腐性能要求较高,玻璃钢是最为理想的选材.本文根据污泥沉积池罩的受力和安装要求,利用大型通用有限元工程设计软件ANSYS对污泥沉积池罩的外形、结构和重量进行了优化设计,最终设计出重量仅为11.2t,直径34m的玻璃钢污泥沉积池罩. 相似文献
955.
Optimal performance of vehicle occupant restraint system (ORS) requires an accurate assessment of occupant injury values including head, neck and chest responses, etc. To provide a feasible framework for incorporating occupant injury characteristics into the ORS design schemes, this paper presents a reliability-based robust approach for the development of the ORS. The uncertainties of design variables are addressed and the general formulations of reliable and robust design are given in the optimization process. The ORS optimization is a highly nonlinear and large scale problem. In order to save the computational cost, an optimal sampling strategy is applied to generate sample points at the stage of design of experiment (DOE). Further, to efficiently obtain a robust approximation, the support vector regression (SVR) is suggested to construct the surrogate model in the vehicle ORS design process. The multiobjective particle swarm optimization (MPSO) algorithm is used for obtaining the Pareto optimal set with emphasis on resolving conflicting requirements from some of the objectives and the Monte Carlo simulation (MCS) method is applied to perform the reliability and robustness analysis. The differences of three different Pareto fronts of the deterministic, reliable and robust multiobjective optimization designs are compared and analyzed in this study. Finally, the reliability-based robust optimization result is verified by using sled system test. The result shows that the proposed reliability-based robust optimization design is efficient in solving ORS design optimization problems. 相似文献
956.
The HUB-CI model is investigated in a telerobotic system in a client/server network to manage the lifecycle of engineering design and prototyping. The purpose of this platform is to support collaborative engineering design and proof of concept to enhance distributed team collaboration and resource utilization. The suggested platform is exemplified in two collaboration support tools and a physical prototyping platform. Structured Co-Insight Management is developed to support innovative idea exchanges and the consensus decision-making during the design process. Conflict/error detection management helps preventing conflicts and errors during the lifecycle of design and development. Physical collaboration over the network occurs when a team controls the telerobot operation during prototyping and testing in design cycles. A pilot system is implemented with a group project for the design of an electronic circuit (including both hardware and software designs). The functional assessment method is used to compare this platform to other collaborative design tools. The system presented offers unique qualitative advantages as an integrated collaboration support system. 相似文献
957.
Today parametric associative CAD systems must help companies to create more efficient virtual development processes. While dealing with complex parts (e.g. the number of surfaces of the solid) no CAD modeling methodology is existing. Based on the analysis of industrial designers' practices as well as student practices on CAD, we identified key factors that lead to better performance. Our objective in this article is to propose a practical method for complex parts modeling in parametric CAD system. An illustration of the performances and the results obtained by this method are presented comparing the traditional method with the proposed one while using an academic case and then an industrial case. 相似文献
958.
S. Chaturvedi C. Dunne Z. Ashktorab R. Zachariah B. Shneiderman 《Computer Graphics Forum》2014,33(8):52-68
An important part of network analysis is understanding community structures like topological clusters and attribute‐based groups. Standard approaches for showing communities using colour, shape, rectangular bounding boxes, convex hulls or force‐directed layout algorithms remain valuable, however our Group‐in‐a‐Box meta‐layouts add a fresh strategy for presenting community membership, internal structure and inter‐cluster relationships. This paper extends the basic Group‐in‐a‐Box meta‐layout, which uses a Treemap substrate of rectangular regions whose size is proportional to community size. When there are numerous inter‐community relationships, the proposed extensions help users view them more clearly: (1) the Croissant–Doughnut meta‐layout applies empirically determined rules for box arrangement to improve space utilization while still showing inter‐community relationships, and (2) the Force‐Directed layout arranges community boxes based on their aggregate ties at the cost of additional space. Our free and open source reference implementation in NodeXL includes heuristics to choose what we have found to be the preferable Group‐in‐a‐Box meta‐layout to show networks with varying numbers or sizes of communities. Case study examples, a pilot comparative user preference study (nine participants), and a readability measure‐based evaluation of 309 Twitter networks demonstrate the utility of the proposed meta‐layouts. 相似文献
959.
Amir Vaxman 《Computer Graphics Forum》2014,33(8):121-131
We present a novel framework for polyhedral mesh editing with face‐based projective maps that preserves planarity by definition. Such meshes are essential in the field of architectural design and rationalization. By using homogeneous coordinates to describe vertices, we can parametrize the entire shape space of planar‐preserving deformations with bilinear equations. The generality of this space allows for polyhedral geometric processing methods to be conducted with ease. We demonstrate its usefulness in planar‐quadrilateral mesh subdivision, a resulting multi‐resolution editing algorithm, and novel shape‐space exploration with prescribed transformations. Furthermore, we show that our shape space is a discretization of a continuous space of conjugate‐preserving projective transformation fields on surfaces. Our shape space directly addresses planar‐quad meshes, on which we put a focus, and we further show that our framework naturally extends to meshes with faces of more than four vertices as well. 相似文献
960.
Structural adhesives are gaining wide recognition by industry as they offer engineering designers greater flexibility to achieve economic and technical advantages. In the marine industry there are potential applications for adhesives in various types of construction, for example, thick steel and composite adherends, (typically 5-15 mm thick). The applications include panels and large pipes. This article is largely concerned with the use of two-part epoxy adhesives. The purpose of this article is to understand and evaluate the weaknesses of adhesives and adherends, in relation to specific applications and to use design and material selection to alleviate them. This understanding can be extended to other thick adherend applications. This article will also highlight the impact of structural epoxy adhesive technology on the design and fabrication of steel, composite, and hybrid constructions. The benefits and inherent limitations that can accrue are quantified through three case studies related to thick adherend connections. 相似文献