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51.
CAD-oriented analytic formulas are presented for calculating the quasistatic TEM parameters of the overlayed supported asymmetric coplanar waveguides (OSACPW). The effect of the thicknesses and the dielectric constants of the overlaying and supporting materials on the quasistatic parameters has been investigated by using the expressions derived by the conformal mapping techniques. Comparisons have also been made between this article's results and the results available in the literature for the conventional coplanar waveguide (CPW) and the asymmetric coplanar waveguide (ACPW). It has been shown that the present formulas can also be used for calculating the quasistatic TEM parameters of the line structures such as the open, the open supported, and the overlayed supported CPW or ACPW. © 1996 John Wiley & Sons, Inc. 相似文献
52.
The possibility of producing carbon black from Iraqi refinery products has been investigated. The products considered as feedstocks included five different furfural extracts from lube oil processing in addition to vacuum residue, reduced crude and a heavy Qaiyarah crude oil. A laboratory-scale experimental apparatus based on the oil furnace process and operated at different air/feed ratio was used to compare the suitability of the feedstocks for carbon black production. The results indicate that the most suitable feedstocks were extracts LVI 60 and LVI 150, and vacuum residue. 相似文献
53.
Shahid M. Ramay Asif Mahmood Hamid M. Ghaithan Nasser S. Al-Zayed Adnan Aslam Abdullah Murtaza Nisar Ahmad Saadat A. Siddiqi Murtaza Saleem 《中国稀土学报(英文版)》2019,37(9):989-994
Dy_2O_3 is a rare earth oxide having a number of advanced applications in various fields including protective or antireflective coatings, Main objective of this novel research work is to check the effect of Cr and Cu addition on different properties of Dy_2O_3 and achievement of antireflective thin films with enhanced abso rption. Thin films of these materials we re deposited using DC magnetron with reactive cosputtering. XRD studies reveals the crystalline nature of thin films having Dy_2O_3(222) reflection in all samples with Cr_2O_3(116) and CuO(111) reflections in Cr and Cu containing compositions. Field emission scanning electron microscopy demonstrates the homogeneous deposition of thin films with uniform shape, size and distribution of grains. Refractive index, extinction coefficient and absorption coefficient significantly increase while optical reflectance decreases with Cr and Cu mediation corroborating an improved antireflective mechanism. The imaginary part of dielectric constant is found to increase slightly with low tangent loss for Cr containing composition co nsidered favorable for energy storage applications. 相似文献
54.
Hybrid Paper–Plastic Microchip for Flexible and High‐Performance Point‐of‐Care Diagnostics 下载免费PDF全文
Mohamed Shehata Draz Maryam Moazeni Manasa Venkataramani Harini Lakshminarayanan Ecem Saygili Nivethitha Kota Lakshminaraasimulu Kamyar Mehrabi Kochehbyoki Manoj Kumar Kanakasabapathy Shirin Shabahang Anish Vasan Mohamad Ali Bijarchi Adnan Memic Hadi Shafiee 《Advanced functional materials》2018,28(26)
A low‐cost and easy‐to‐fabricate microchip remains a key challenge for the development of true point‐of‐care (POC) diagnostics. Cellulose paper and plastic are thin, light, flexible, and abundant raw materials, which make them excellent substrates for mass production of POC devices. Herein, a hybrid paper–plastic microchip (PPMC) is developed, which can be used for both single and multiplexed detection of different targets, providing flexibility in the design and fabrication of the microchip. The developed PPMC with printed electronics is evaluated for sensitive and reliable detection of a broad range of targets, such as liver and colon cancer protein biomarkers, intact Zika virus, and human papillomavirus nucleic acid amplicons. The presented approach allows a highly specific detection of the tested targets with detection limits as low as 102 ng mL?1 for protein biomarkers, 103 particle per milliliter for virus particles, and 102 copies per microliter for a target nucleic acid. This approach can potentially be considered for the development of inexpensive and stable POC microchip diagnostics and is suitable for the detection of a wide range of microbial infections and cancer biomarkers. 相似文献
55.
Adnan Ahmed Andrew J. Neely Krishna Shankar 《Metallurgical and Materials Transactions A》2011,42(3):795-815
This article studies the influence of nanometric (n-SiCp) and micrometric-scale SiC particulates (μ-SiCp) on the tensile properties of the Al 7075 alloy. The unreinforced Al and its composites were synthesized using the powder
metallurgy (P/M) route and were tested uniaxially in tension at both room and elevated temperatures. Aging behavior was studied
to observe any effect of the reinforcement on the aging kinetics and hardness of the composites. X-ray diffraction was performed
to determine the crystal structures of the raw materials and any reaction phase formed in the composites. The n-SiCp were not dispersed uniformly in the Al matrix and clustered mainly at the grain boundaries. The stiffness of the composites
increased and the ductility decreased with an increase in the volume fraction of the n-SiCp. The n-SiCp proved to be a better reinforcement than the traditional μ-SiCp in terms of imparting higher ductility to the composite. Fractography and microscopy using optical, scanning electron, and
transmission electron microscopes were performed for failure and microstructural analysis of all the materials. At room temperature,
the fracture altered from ductile in the unreinforced Al to brittle in the composites. At an elevated temperature, the fracture
mechanism transformed from brittle to ductile rupture in the composites. 相似文献
56.
Mika Kettunen Adnan S Abu‐Surrah Timo Repo Markku Leskel 《Polymer International》2001,50(11):1223-1227
Synthesis of functional aliphatic polyketones was achieved by co‐ and terpolymerization of the strained exo‐methylenecycloalkane, methylenecyclopropane (MCP), and also the dienes 1,5‐hexadiene, 1,7‐octadiene and 1,6‐heptadien‐4‐ol, with carbon monoxide and propene, using the dicationic palladium(II) phosphine complex [Pd(dppp) (NCCH3)2](BF4)2 (I) (dppp is 1,3‐bis(diphenyl‐phosphino)propane) as the catalyst precursor. The resulting MCP/CO copolymer contains both ring‐opened and cyclic microstructures. Ring‐opening copolymerization yields exo‐methylene functionalized polyketone. In contrast to hexadiene/carbon monoxide copolymer (Hx/CO), no ring structures were observed in the alternating octadiene/carbon monoxide (Oc/CO) and heptadien‐4‐ol/carbon monoxide (Hp‐ol/CO) copolymers. The remaining double bonds were left intact to yield polymers with olefinic functionalities in the side chains. © 2001 Society of Chemical Industry 相似文献
57.
Interface structure of diffusion bonded duplex stainless steel and medium carbon steel couple 总被引:2,自引:0,他引:2
Diffusion bonding of duplex stainless steel to medium carbon steel was carried out with different temperatures for sound bonds. In the bonding process, relatively intermediate temperatures such as 750, 800, 850 and 900 °C were used with a bonding time of 30 min. In this study, microstructural changes and mechanical properties in the interface region of duplex stainless steel and medium carbon steel couples were determined. The results showed that, in interface region, Cr23C6 was formed on the stainless steel side, while ferrite formation was observed on the carbon steel side as a result of mutual diffusion of C and Cr. 相似文献
58.
This work is concerned with the effects of environmental factors on the adhesion and durability characteristics of epoxy-bonded concrete prisms. The results indicate that the presence of liquid water at the interfacial zone during the epoxy injection process disrupts the initial bond configurations. The freezing and thawing up to about 40 cycles do not have a significant effect on the bond stability. An adequate degree of chemical stability is maintained in the bond line by the epoxy adhesives after 120 days of exposure to corrosive environments such as MgSO4 and MgCl2. However, there is a pronounced effect of these chemical substances on the concrete strength. The load-bearing capacity of epoxy-bonded concrete prisms decreases with increasing temperature. Despite this fact, the EP3-bonded concrete prisms give relatively high joint strengths at temperatures up to 100 °C. 相似文献
59.
Metal oxide nanosheets have potential applications in novel nanoelectronics as nanocrystal building blocks. In this work, the devices with a structure of Au/p-type Co3O4 nanosheets/indium tin oxide/glass having bipolar resistive switching characteristics were successfully fabricated. The experimental results demonstrate that the device have stable high/low resistance ratio that is greater than 25, endurance performance more than 200 cycles, and data retention more than 10,000 s. Such a superior performance of the as-fabricated device could be explained by the bulk film and Co3O4/indium tin oxide glass substrate interface effect. 相似文献
60.
Awni Al-Otoom Mamdouh Allawzi Adnan M. Al-Harahsheh Mohammad Al-Harahsheh Randa Al-Ghbari Raeda Al-Ghazo Husam Al-Saifi 《Energy》2009,34(9):1310-1314
Different parameters affecting the behavior of froth flotation of Jordanian tar sand, obtained from the Dead Sea area, were studied. This study was performed in a modified fluidized bed floatator. The effects of the addition of a flotation agent, NaOH, temperature and flotation time on the beneficiation of bitumen in the froth were investigated. It was found that the beneficiation factor in the froth increased with the increase of temperature and flotation time. However, the amount of base (NaOH) and the flotation agent were found to have a negative effect on that factor. A regression model based on a full factorial experimental design results was obtained with a significant correlation coefficient. The optimum beneficiation factor was found to be 7.2 and the bitumen content in the froth was found to be 79% in the froth, which was obtained at 0.2 gNaOH/L, zero agent, 80 °C, and 30 min. 相似文献