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951.
Low corrosion optically clear adhesives for conducting glass: I. Effects of N,N‐diethylacrylamide and acrylic acid mixtures on optically clear adhesives 下载免费PDF全文
This study designs less corrosive optically clear adhesives (OCAs) with good rework properties, where copolymer and glycidyl methacrylate (GMA) are cured by ultraviolet to form OCAs. The copolymer are synthesized by using N,N‐diethylacrylamide (DMA), acrylic acid (AA), and 2‐ethylhexyl acrylate. The DMA and AA could form acid–base interaction and therefore lower the corrosion on metallic substrate caused by AA. Copolymer is applied in OCAs, as different adhesive properties are presented. In terms of the adhesive property of OCAs, the peel strength, shear strength, and transmittance property are decreased when the GMA concentration is increased. The tack and haze are enhanced accordingly. After 7 days' standing at 60 °C and 90% RH, OCAs have no obvious corrosion on the conductive glass circuits, and there is no residue after peeling off. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135, 46277. 相似文献
952.
Adaptive Polymeric Coatings with Self‐Reporting and Self‐Healing Dual Functions from Porous Core–Shell Nanostructures 下载免费PDF全文
Jun‐Peng Wang Jun‐Kuo Wang Qiong Zhou Zhan Li Yongsheng Han Yan Song Shuo Yang Xiaoke Song Tao Qi Helmuth Möhwald Dmitry Shchukin Guo Liang Li 《大分子材料与工程》2018,303(4)
In biological system, early detection and treatment at the same moment is highly required. For synthetic materials, it is demanding to develop materials that possess self‐reporting of early damage and self‐healing simultaneously. This dual function is achieved in this work by introducing an intelligent pH‐responsive coatings based on poly(divinylbenzene)‐graft‐poly(divinylbenzene‐co‐methacrylic acid) (PDVB‐graft‐P(DVB‐co‐AA)) core–shell microspheres as smart components of the polymer coatings for corrosion protection. The key component, synthesized PDVB‐graft‐P(DVB‐co‐AA) core–shell microspheres are porous and pH responsive. The porosity allows for encapsulation of the corrosion inhibitor of benzotriazole and the fluorescent probe, coumarin. Both loading capacities can be up to about 15 wt%. The polymeric coatings doped with the synthesized microspheres can adapt immediately to the varied variation in pH value from the electrochemical corrosion reaction and release active molecules on demand onto the damaged cracks of the coatings on metal surfaces. It leads simultaneously to the dual functions of self‐healing and self‐reporting. The corrosion area can be self‐reported in 6 h, while the substrate can be protected at least for 1 month in 3.5 wt% NaCl solution. These pH‐responsive materials with self‐reporting and self‐healing dual functions are highly expected to have a bright future due to their smart, long‐lasting, recyclable, and multifunctional properties. 相似文献
953.
954.
Preparation of the ternary carbide Cr2AlC was conducted by combustion synthesis in the mode of self-propagating high-temperature synthesis (SHS) from the Cr2O3-Al-Al4C3 powder compact. Effects of the contents of Al and Al4C3 on the product composition and combustion behavior were studied by formulating the reactant mixture with a stoichiometric proportion of Cr2O3:Al:Al4C3 = 3:5x:y, where x and y varied from 1.0 to 1.5. When compared to those of the powder compact with Cr2O3:Al:Al4C3 = 3:5:1 (i.e., x = y = 1.0), the combustion temperature and reaction front velocity increased with content of Al, but decreased with that of Al4C3. Besides Cr2AlC and Al2O3, the final products always contained a secondary phase Cr7C3 that was substantially reduced by adopting additional Al and Al4C3 in the reactant compacts. For the sample with Cr2O3:Al:Al4C3 = 3:7.5:1 (x = 1.5), solid state combustion reached a peak temperature of 1245 °C and yielded Cr2AlC with a trivial amount of Cr7C3. Although Cr7C3 was lessened by introducing extra Al4C3, the increase of Al4C3 from y = 1.1 to 1.5 produced almost no further reduction of Cr7C3 in the final product. This is partly attributed to the low combustion temperature in the range of 1065-1095 °C for the samples with additional Al4C3, and in part, due to the role of Al4C3 which might react with Cr to form Cr7C3, Cr2Al, and Cr2AlC. 相似文献
955.
Ganghua ZhangGuobao Li Fuqiang HuangFuhui Liao Kuo LiYinxia Wang Jianhua Lin 《Journal of Alloys and Compounds》2011,509(41):9804-9808
Superconductors Ba1−xKxBiO3 and body-centered double perovskites Ba1−xKxBi1−yNayO3 have been selectively synthesized by a facile hydrothermal route. The appropriate ratio and adding sequence of initial reagents, alkalinity, reaction temperature and time are the critical factors that influence the crystal growth of the compounds. The purity and homogeneity of the crystals were detected by the ICP, SEM, EDX and TEM studies. Magnetic measurements show that the superconducting transition temperatures TC of Ba1−xKxBiO3 decrease from 22 K (for x = 0.35) to 8 K (for x = 0.55) with increasing the K doping level. 相似文献
956.
本体作为领域知识的表示方法,已经成为语义Web的基础。本体通常由领域专家建立,用于表示领域中概念以及概念与概念之间的关系。但这也使得普通用户难以理解本体中描述的信息。普通用户往往希望本体中的信息能够以自然语言的形式描述。这正是本文讨论的主要问题。本文采用分治策略,利用基于嵌套复杂模板的解决方案,设计并实现了本体知识文摘的算法。我们开发了一个原型系统SWARMS,并将该文摘算法进行了运用。初步的实验表明,本文提出的方法取得较好的结果。 相似文献
957.
The present study investigated the effects of drawing direction (top‐down or bottom‐up) and orientation angle (0°, 60°, or 300°) on the stability of straight‐line drawing with varied line length (5.7, 11.4, or 17.1 cm) of elderly Taiwanese adults. These three independent variables were within‐subject factors. In total, 38 elderly adults participated. The straight‐line drawing task was performed on an iPad using an electronic pen. Straight‐line drawing performance was analyzed using three‐way repeated analysis of variance measures. The results indicated that the error rate was significantly higher in the top‐down condition than in the bottom‐up condition and was higher for the 5.7‐cm line length than for the 11.4 or 17.1 cm lengths. In addition, the average drawing speed in the top‐down condition was significantly greater than that in the bottom‐up condition and was significantly greater at 17.1 and 11.4 cm than at 5.7 cm. The orientation angle also significantly affected the average drawing speed, which demonstrated that the 60° condition yielded a significantly greater speed than the 0° or 300° conditions. Our findings have implications for product design and computer–human interface design for seniors. Further studies are needed to determine whether these findings can be generalized to more complex motor movements and cognitive abilities. 相似文献
958.
Wen-Hung Kuo 《Information Processing Letters》2006,97(2):64-67
Both the building cost and the multiple-source routing cost are important considerations in construction of a network system. A spanning tree with minimum building cost among all spanning trees is called a minimum spanning tree (MST), and a spanning tree with minimum k-source routing cost among all spanning trees is called a k-source minimum routing cost spanning tree (k-MRCT). This paper proposes an algorithm to construct a spanning tree T for a metric graph G with a source vertex set S such that the building cost of T is at most 1+2/(α−1) times of that of an MST of G, and the k-source routing cost of T is at most α(1+2(k−1)(n−2)/k(n+k−2)) times of that of a k-MRCT of G with respect to S, where α>1, k=|S| and n is the number of vertices of G. 相似文献
959.
960.
Feedforward active noise control (ANC) system are widely used to reduce the wide-band noise in different application. In feedforward ANC systems, when the noise source is unknown, the misplacement of the reference microphone may violate the causality constraint. We present a performance analysis of the feedforward ANC system under a noncausal condition. The ANC system performance degrades when the degree of noncausality increases. This research applies the microphone array technique to feedforward ANC systems to solve the unknown noise source problem. The generalized cross-correlation (GCC) and steering response power (SRP) methods based on microphone array are used to estimate the noise source location. Then, the ANC system selects the proper reference microphone for a noise control algorithm. The simulation and experiment results show that the SRP method can estimate the noise source direction with 84% accuracy. The proposed microphone array integrated ANC system can dramatically improve the system performance. 相似文献