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101.
Woo‐Il Baek Hem Raj Pant R. Nirmala Ki‐Taek Nam Hyun‐Ju Oh Hak‐Yong Kim 《Polymer International》2012,61(5):844-849
In the present study, the effect of adhesive on the morphology of different electrospun polymeric mats was investigated. The modification of two polymers, poly(methyl methacrylate) and poly(vinyl chloride), was carried out by blending the polymers with different amounts of poly(butyl acrylate) (PBA) adhesive to investigate the effect of different amounts of adhesive with heat hardener in hybrid mats. The introduction of various concentrations of PBA into different polymer solutions led to the formation of point‐bonded electrospun fibrous mats. Scanning electron microscopy images indicated that point‐bonded polymer/adhesive fibers were uniformly distributed throughout the mats. Fourier transform infrared spectrometry, contact angle measurements and thermogravimetric analysis were used to study the different properties of the hybrid mats. The tensile strength of the blended fibrous electrospun mats was increased effectively. This enhancement of the mechanical properties of the mats due to the presence of adhesive increases the number of potential applications of the electrospun mats, especially for mechanically weak polymers. Copyright © 2012 Society of Chemical Industry 相似文献
102.
Sung Hyun Hwang Soon Ki Kim Jun-Tae Nam Jong-Sung Park 《International Journal of Hydrogen Energy》2021,46(1):1076-1084
Composite anodes of nano-sized Ni and Ba(Zr0.85Y0.15)O3-δ (BZY) were fabricated by infiltrating a single precursor solution of BZY and Ni into the BZY scaffold, and decreasing the calcination temperature to 1173 K. This decrease in the fabrication temperature of the Ni-cermet anode prevents the chemical reaction between the electrolyte and nickel, thus preventing a reduction in the conductivity of the electrolyte. By optimizing the amount of Ni in the Ni-cermet and infiltrating additional catalysts such as CeO2 and Pd, the non-ohmic ASR of the Ni-cermet anode could be optimized. This resulted in a smaller non-ohmic ASR of anode than one that was fabricated by the conventional co-sintering method. Consequently, a high power density of 790 mW/cm2 at 973 K can be obtained from electrolyte-supported cells. 相似文献
103.
This review introduces recent changes regarding measurement of preferences brought about by the discovery of false preferences that occur with paired preference testing. Testing protocols are examined critically. False preferences result from a response bias elicited by factors distinct from sensory properties of products being tested that can distort results. Statistical approaches to circumventing this problem are examined. Alternative methods are being developed to eliminate false preferences based on understanding information processing in the brain. This has led to development of disruptive experimental preference testing protocols based on hypothesized use of processing subroutines in the brain to protect the central processing system from overload. These disruptive protocols suppress response bias. Paired preference testing is designed to predict consumer behavior. A paucity of studies addressing whether they do is put into perspective. 相似文献
104.
Nam Seung-Hee Kim Young-Min Walsh Marie K. Yim Sun-Hee Eun Jong-Bang 《Food science and biotechnology》2016,25(1):31-39
This study was performed to characterize pear protease proteolytic activity and investigate the use of pear protease as a meat tenderizer. Pear protease was purified and stabilized by 5% dextrin during lyophilization (dry) or concentration (liquid). Pear protease was further characterized with respect to pH, thermodynamics, and enzyme kinetics. Pear protease was stable at a pH range of 5-8 with an optimum pH of 6.5. From Arrhenius plots, liquid protease showed higher temperature dependency (23.49 kJ/mol) than dry protease (18.62 kJ/mol) due to its higher activation energy. The kcat/Km, catalytic efficiency of enzyme, was similar with 2.9 and 2.7 µM/min with dry and liquid proteases. Pear protease was evaluated for its proteolytic activities with casein and beef myofibrillar proteins by individually and combination with fig and kiwifruit proteases. These result indicated that pear and kiwifruit proteases could be complementary to be a desirable product for meat tenderization. 相似文献
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107.
Boo Hyun Nam Jinwoo An Mooyeon Kim Michael R. Murphy Zhanmin Zhang 《International Journal of Pavement Engineering》2016,17(8):680-697
Structural evaluation provides valuable information about the expected behaviour and response of pavements and can be used at the network level of pavement management to prioritise projects. The falling weight deflectometer (FWD) can be used to identify the beginning and end of management sections and group pavement sections with similar structural capacities. The structural condition index (SCI) was developed as a screening tool for the pavement network-level evaluation, and the FWD data are used to determine the SCI. For the successful implementation of the SCI concept at the network level, one of the critical issues is the accuracy of the index. This article evaluates the accuracy of the SCI and also discusses a concept and procedure how to improve the SCI and its algorithm for low-volume flexible pavements. A case study (Texas) illustrates that the original SCI algorithm underestimates the existing structural condition, resulting in overestimated treatments in the pavement maintenance and rehabilitation. 相似文献
108.
Adhesion between polymer surface modified by graft polymerization and tissue during surgery using an ultrasonically activated scalpel device 下载免费PDF全文
Kwangwoo Nam Takuya Iwata Tsuyoshi Kimura Hiroki Ikake Shigeru Shimizu Toru Masuzawa Akio Kishida 《应用聚合物科学杂志》2014,131(20)
In the field of surgery, achieving adhesion between a polymer implant and tissue poses a challenge considering that suturing is not appropriate for the stability of such implants. An ultrasonically activated scalpel that generates heat by mechanical vibration and promotes adhesion between a polymer implant and native tissue by pressing the two materials together has very good potential for application in the field. To determine the type of polymer that is suitable for the purpose, we investigated polyethylene (PE) and polystyrene (PS) films, the surfaces of which were activated by corona discharge. Graft polymerization was then performed on the corona‐treated surfaces to vary their properties. The corona‐treated PE and PS films grafted with poly(acrylic acid), poly(methacrylic acid), poly(vinyl benzylacrylic acid), and poly(hydroxylethyl acrylate), respectively, adhered to the tissue when the ultrasonically activated scalpel was applied. The heat generated by the mechanical vibration and the applied pressure enabled the carboxyl or hydroxyl groups to bond with the proteins in the extracellular matrix. We therefore concluded that it was possible to integrate this technique in the development of new types of polymer devices that could be stably implanted in a living body. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40885. 相似文献
109.
Abstract: Hydrocarbons, gas compounds, and off‐odor volatiles were determined for irradiated (0 or 5 kGy) commercial sausages with different fat contents (16% and 29%) during a 60‐d storage period at 4 °C. Total of 4 hydrocarbons (C14:1, C15:0, C16:2, and C17:1) were detected only in irradiated sausages: the amount of C16:2 was the highest, followed by C17:1, C14:1, and C15:0. The concentrations of hydrocarbons decreased significantly (P < 0.05) with storage, but were still detectable at the end of 60‐d storage. Irradiated sausages produced significantly higher amounts of CO than the nonirradiated ones. CH4 was detected only in irradiated sausages. Dimethyl disulfide was detected only in irradiated sausages and its concentration decreased significantly (P < 0.05) with storage. Fat content of sausages showed a significant effect on the production and retention of hydrocarbons, gas compounds, and sulfur volatiles in irradiated sausages during storage. Some hydrocarbons (C16:2, C17:1, C14:1, and C15:0), CH4, and dimethyl disulfide were only found in irradiated sausages indicating that these compounds can be used as potential markers for irradiated sausages. 相似文献
110.
Jeong-Hwan Song Kyung-Su Nam Jung-In Moon Young-Jun Choi Dae-Young Lim 《Metals and Materials International》2014,20(3):451-458
Oxide layers were prepared on Al-1050 substrates by an environmentally friendly plasma electrolytic oxidation process using an alkaline solution of Na2SiO3 (8 g/L) and NaOH (3 g/L) as the electrolyte. The effects of three different duty cycles (20%, 40%, and 60%) on the structure and hardness of the oxides were investigated. XRD analysis revealed that the oxides were mainly composed of α-Al2O3, γ-Al2O3, and mullite. The proportion of each phase depended on various electrical parameters, such as the duty cycle and frequency. The morphology, thickness, and the elemental distribution of the oxides were examined by scanning electron microscopy and energy dispersive spectroscopy. The thicknesses of the oxides were found to vary from 20 μm to more than 60 μm for various duty cycles, when identical treatment durations were used. The oxidation treatment also resulted in good adhesion between the oxide layer and the substrate. SEM images indicated that the oxide layers formed at the 60% duty cycle exhibited relatively coarser surfaces with larger pore sizes and sintering particles, and slower growth rates than did those formed at the 20% duty cycle, under identical treatment durations. The oxides prepared at the 20% duty cycle showed smooth surfaces. The oxides layers were found to improve the micro-hardness of Al-1050. In particular, the oxide layers formed at the 40% duty cycle exhibited relatively better micro-hardness owing to their compact microstructures. 相似文献