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991.
提出一种新型节能插座,该插座能够通过对外界用电情况的智能检测以及外界的控制信号收集实现对电源的控制。智能插座由PIC12F615单片机主控模块、电源稳压模块、浪涌保护模块、红外信号检测模块、按键检测模块与继电器控制模块及电压取样模块组成。通过检测插座回路的微小电流,获知外界用电情况以及通过对外界红外信号的识别和对按键信号的识别控制继电器的开关动作,实现对电源的智能控制。  相似文献   
992.
对于能量供应有限制的硬实时多核系统,最差情况下的能量消耗WCEC(Worst-Case Energy Consumption)是一个非常关键的问题。随着芯片工艺的发展,顺序指令预取技术可以减少缓存WCEC。为了提高指令预取的最差情况下的节能效率,提出结合指令预取和共享缓存划分的硬实时多核系统缓存WCEC优化方法。该方法通过线性规划方程ILP(Integer-Linear Programing)为每个核分配L2缓存划分因子和调整每个硬实时子任务的指令预取度,在保证硬实时系统满足时间截止期的情况下,最小化其缓存WCEC。对DEBIE系统进行实例分析,实验结果表明优化方法是有效的,在保证系统满足时间截止期的情况下,优化后的缓存WCEC比没有指令预取优化的缓存WCET平均减少了22.5%。  相似文献   
993.
合同能源管理是一种新型的市场化节能机制,是推动宁夏节能降耗工作和经济集约发展的有力举措;在宁夏有着广泛的发展前景。  相似文献   
994.
以纳米SiO2粉末与高折射率矿物粉末、增强纤维及高温收缩抑制剂,经千法混合后压制成型,制备较大体积密度的纳米节能材料。通过压制试验,研究了原料混合粉末在模具内的体积变化,探讨了物料中的气体对体积收缩率的影响,得到了材料体积密度与成型压力的关系。通过背温试验,将体积密度450kg/m3的纳米节能材料与现有市场上的复合反射绝热材料的绝热效果进行对比。结果表明,对于同样20mm厚度的两种材料,纳米节能材料热面温度稳定在668℃时,其冷面温度只有140℃。而复合反射材料热面温度稳定在641℃时,冷面温度高达229℃。纳米节能材料的绝热效果明显优于复合反射材料。  相似文献   
995.
In diesem Beitrag wird über Ergebnisse von experimentellen und numerischen Untersuchungen an vergrouteten Rohr‐in‐Rohr‐Verbindungen berichtet, die am Institut für Stahlbau der Leibniz Universität Hannover durchgeführt wurden. Diese sogenannten “Grouted Joints” kommen z. B. als Verbindungselemente zwischen dem im Boden eingerammten Pfahl und dem Turm einer Offshore‐Windenergieanlage zum Einsatz. An deutlich kleineren Prüfkörpern wurden Axialdruckversuche im Labor durchgeführt, um den Unterschied zwischen glatten und gerippten Stahlrohrmantelflächen im Grenzzustand der Tragfähigkeit und Ermüdung aufzuzeigen. Dabei kamen auch verschiedene Füllmaterialien für den Ringspalt zum Einsatz. Die Tragfähigkeit bei den Prüfkörpern mit glatten Rohrmantelflächen ist hauptsächlich von der Haftfestigkeit des Füllmaterials auf den Stahloberflächen und deren Beschaffenheit abhängig. Durch die Anordnung von Schubrippen kann die Trag‐ und Ermüdungslast um ein Vielfaches gegenüber der glatten Variante gesteigert werden. Dies ist hauptsächlich auf die Wirkung von Druckstreben zwischen den Schubrippen zurückzuführen, deren Tragfähigkeit sich mit zunehmender Druckfestigkeit des Füllmaterials erhöht. Mit einem Bemessungsmodell kann unter Berücksichtigung der Druckstrebentragfähigkeit und Anzahl der Schubrippen die Traglast von Grouted Joints abgeschätzt werden. Static and dynamic axial compression tests on grouted tube‐in‐tube connections with various grout materials. This paper summarises static and dynamic axial compression tests on small scale grouted joints for offshore wind energy converters. The connection is mostly used between driven monopiles and tower sections as tube‐in‐tube connection. The gap between the tubes is filled with grout materials. The test series comprises grouted joints with smooth and ribbed surfaces of the tubes which are loaded by axial compression. The ultimate and fatigue limit state of the connection can be increased with shear keys along the overlapped length of the tubes to get a ribbed contact surface to the grout. In this case the axial load is transferred by compression struts between the shear keys. The bearing capacity depends mainly on the compressive strength of the grout and the geometry of the shear keys. In addition to the experimental results an analytical design concept is presented within this paper for grouted joints with shear keys. With the analytical model the axial load capacity of the grouted joint can be determined under consideration of the compression struts and number of shear keys.  相似文献   
996.
The new VDI guideline 3925 presents assessment tools for the comparison of economic, ecological and also social aspects of different waste treatment processes. Objective of the guideline is to describe the application of suitable scientific and technical assessment methods to waste management strategies. The methods, their applicability, complexity, opportunities and limits are illustrated using practical examples.  相似文献   
997.
In this paper, a thermodynamic analysis of non-isothermal mixing's influence on the energy target of water-using network is presented. Firstly, water streams in the network are divided into two categories, and then based on the classification all the non-isothermal mixing patterns between two streams are defined. Through thermodynamic analysis from energy composite curve of hot and cold water streams, the influences of non-isothermal mixing on the energy target of water-using network are explored and some mixing rules are obtained, which can be used to simplify the heat exchanger network of a given water-using system and improve the system's energy performance through identifying the beneficial non-isothermal mixings. The applicability of these rules is illustrated by an example in the paper and the result is very encouraging.  相似文献   
998.
Three dimensional non-linear finite element analyses of Lap Shear Joints (LSJs) made with curved laminated FRP composite panels having pre-existing delaminations between the first and second plies of the strap adherend have been carried out using contact and Multi-Point Constraint elements (MPC). Progressive growth of delamination has been simulated by sequential release of the MPC elements. Strain Energy Release Rate (SERR), being an indicative parameter has been computed using Virtual Crack Closure Technique (VCCT) for assessing the growth and propagation of the delamination damage fronts. The inter-laminar stresses and the SERRs at the two fronts of the pre-embedded delamination are found to be significantly influenced by the delamination size. The three individual modes of SERR on the two delamination fronts are found to be much different from each other, indicating dissimilar rates of propagation. The curvature geometry of adherends significantly influences the SERR values. It is seen that decrease of radius of curvature of adherend panels, keeping their widths unchanged, increases the SERR values. Flatter FRP composite adherends have superior resistance to delamination damage propagation as compared to LSJs made with curved composite laminated panels.  相似文献   
999.
Four process alternatives for the production of isoamyl acetate, by the liquid phase esterification of acetic acid with isoamyl alcohol, were evaluated by simulation in terms of product purity, energy integration and economics. The analysis involves a transition from conventional (two structures that use acetic acid or alcohol in excess) to hybrid membrane process (two distillation–pervaporation hybrid systems). Acetate recovery is identified as a crucial factor to minimize energy costs in all considered processes. For conventional processes, the amount of energy required for separation, at low acetate recovery levels, is considerably lower if acetic acid is used in excess. For the hybrid processes, there is an optimum value of acetate recovery that minimizes the total required heat duty and membrane area. Hybrid distillation–pervaporation process allows obtaining the specified product purity with lower energy requirements and more economical tradeoffs than the considered conventional processes. The economic optimum design maximizes energy savings and minimizes total annualized costs. After optimization and energy integration, the best process alternative includes, in a hybrid system, one packed bed reactor, two pervaporation units and a distillation column.  相似文献   
1000.
Lead-free 0.9BaTiO3-0.1(Bi0.9Na0.1)(In0.8Zr0.2)O3 (0.9BT-0.1BNIZ) ferroelectric relaxor ceramic was synthesized by solid-state reaction method. A dense microstructure and fine grain size was obtained with addition of BNIZ content. The dielectric behaviors indicated the dominance of ergodic relaxor phase. The 0.9BT-0.1BNIZ ceramic was found to possess an enhanced recoverable energy density (WR~1.33?J/cm3) and efficiency (η~88%) under 18?kV/mm at room temperature. What’s more, WR is maintained ≥0.53?J/cm3 with η?≥?94% under 10?kV/mm and the variation of WR is less than 15% over 25~140?°C. The high stability of energy storage properties is mainly ascribed to the characteristics of ergodic relaxor phase. The stored energy was released in sub-microseconds (~0.19?μs). The superior current density (CD~796?A/cm2) and the power density (PD~39.8?MW/cm3) were obtained simultaneously. The enhanced WR and the superior charge-discharge performances strongly demonstrate that the BT-based ceramics are promising candidates of high-power pulse capacitor applications.  相似文献   
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