全文获取类型
收费全文 | 1175篇 |
免费 | 40篇 |
国内免费 | 2篇 |
专业分类
电工技术 | 10篇 |
综合类 | 2篇 |
化学工业 | 295篇 |
金属工艺 | 32篇 |
机械仪表 | 27篇 |
建筑科学 | 32篇 |
矿业工程 | 2篇 |
能源动力 | 70篇 |
轻工业 | 105篇 |
水利工程 | 2篇 |
石油天然气 | 16篇 |
无线电 | 88篇 |
一般工业技术 | 289篇 |
冶金工业 | 64篇 |
原子能技术 | 18篇 |
自动化技术 | 165篇 |
出版年
2024年 | 3篇 |
2023年 | 17篇 |
2022年 | 56篇 |
2021年 | 62篇 |
2020年 | 44篇 |
2019年 | 37篇 |
2018年 | 59篇 |
2017年 | 52篇 |
2016年 | 42篇 |
2015年 | 28篇 |
2014年 | 46篇 |
2013年 | 102篇 |
2012年 | 48篇 |
2011年 | 76篇 |
2010年 | 63篇 |
2009年 | 62篇 |
2008年 | 58篇 |
2007年 | 57篇 |
2006年 | 43篇 |
2005年 | 39篇 |
2004年 | 31篇 |
2003年 | 21篇 |
2002年 | 15篇 |
2001年 | 14篇 |
2000年 | 5篇 |
1999年 | 9篇 |
1998年 | 11篇 |
1997年 | 12篇 |
1996年 | 6篇 |
1995年 | 9篇 |
1994年 | 4篇 |
1993年 | 13篇 |
1992年 | 5篇 |
1991年 | 8篇 |
1990年 | 3篇 |
1989年 | 9篇 |
1988年 | 5篇 |
1987年 | 6篇 |
1986年 | 6篇 |
1985年 | 6篇 |
1984年 | 7篇 |
1982年 | 5篇 |
1980年 | 3篇 |
1979年 | 4篇 |
1978年 | 3篇 |
1977年 | 1篇 |
1976年 | 1篇 |
1975年 | 1篇 |
排序方式: 共有1217条查询结果,搜索用时 15 毫秒
1.
Catalysis Letters - An environmentally benign process for synthesizing 4-methoxyphenol through methylation of hydroquinone using polystyrene immobilized Bronsted acidic ionic liquid is presented.... 相似文献
2.
3.
Manoj Karakoti Ritu Jangra Sandeep Pandey Pawan Singh Dhapola Sunil Dhali Suman Mahendia Pramod K Singh Nanda Gopal Sahoo 《International Journal of Applied Ceramic Technology》2020,17(4):1899-1908
This study deals with the utility of mini spray dryer process to improve the dispersibility, of graphene oxide(GO) and its application for high-performance supercapacitor. Initially, the neutral solution of GO was obtained using the modified Hummer's method. After this, the prepared GO solution was processed by mini spray dryer to obtain a more purified, lighter, and dispersed form of GO which is named as spray dryer processed GO (SPGO). The SPGO thus obtained showed excellent dispersibility behavior with various solvents, which is not found in case of conventional oven drying. Furthermore, utility of SPGO and its reduced form (r-SPGO) for supercapacitor applications have been investigated. Results obtained from the cyclic voltammetry(CV) analysis, impedance, and charge-discharge behavior of supercapacitor fabricated using r-SPGO shows enhanced features. Therefore, the simple spray dried GO and its reduced form, that is, r-SPGO can be utilized as a potential candidate for the supercapacitor application. Herein, as synthesized SPGO exhibited the specific capacitance of 12.07 and 37.6 F/g with PVA-H3PO4 and 1 mol/L H3PO4, respectively, at a scan rate of 5 mV/s. On the other hand, reduced form of SPGO, that is, r-SPGO showed the specific capacitance of 27.16 and 230 F/g with PVA-H3PO4 and 1 mol/L H3PO4, respectively. 相似文献
4.
Densification of a-Sic powders with no premixed sintering aids (type 1) and with premixed B and C (type 2) was investigated by sintering them at 2150° to 2200°C for 30 min. Flexure strengths, Weibull moduli, and fracture flaws were characterized for type 2 α-SiC only. The results were compared with those for a state-of-the-art sintered a-Sic material. 相似文献
5.
This paper deals with the application of continuous thermodynamics to light and heavy oil systems using the Peng- Robinson equation of state. The composition of the high molar mass components in a reservoir oil is described by a continuous distribution function of some characterizing quantity, e.g. molar mass or boiling temperature. Numerical Gaussian quadrature methods are used to generate pseudo-components and their mole fractions from distribution data. Several examples are presented for phase equilibria of solvent/crude oil systems. The results showed that semi-infinite distribution functions, such as the Γ function, cannot be applied to all cases, e.g. dew point calculations. The Gauss- Legendre quadrature method coupled with spline fitting worked best for heavy oil systems. 相似文献
6.
Lin Ray Y. Warner Sunil G. Blue Craig A. Chen C. C. Eppich Chris A. Blue Randall A. 《JOM Journal of the Minerals, Metals and Materials Society》1994,46(3):26-30
JOM - Infrared processing is a newly developed technique for materials processing. Key features include rapid processing, simplicity, and low cost. Because of the rapid processing, very little... 相似文献
7.
8.
A novel method for the preparation of short nylon fiber–natural rubber composites was developed in which short fibers chopped to approximately 6 mm were incorporated in the latex stage and processed into sheet form. By this method, mixing cycle time was reduced without compromising the fiber dispersion. Fiber breakage during mixing was reduced. The new composites when compounded with a dry bonding system based on hexamethylenetetramine, resorcinol and hydrated silica (HRH) showed improved modulus, tensile strength and abrasion resistance compared to conventional composites. Tear strength, resilience, and compression set were similar to the conventional composites. SEM analysis indicated better interaction between matrix and fibers in the case of latex master batch. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008 相似文献
9.
10.
Sudip Adhikari Sunil Adhikary Ashraf M.M. Omer Mohamad Rusop Hideo Uchida Tetsuo Soga Masayoshi Umeno 《Diamond and Related Materials》2005,14(11-12):1824
Nitrogenated diamond-like (DLC:N) carbon thin films have been deposited by microwave surface wave plasma chemical vapor deposition on silicon and quartz substrates, using argon gas, camphor dissolved in ethyl alcohol composition and nitrogen as plasma source. The deposited DLC:N films were characterized for their chemical, optical, structural and electrical properties through X-ray photoelectron spectroscopy, UV/VIS/NIR spectroscopy, Raman spectroscopy, atomic force microscope and current–voltage characteristics. Optical band gap decreased (2.7 to 2.4 eV) with increasing Ar gas flow rate. The photovoltaic measurements of DLC:N / p-Si structure show that the open-circuit voltage (Voc) of 168.8 mV and a short-circuit current density (Jsc) of 8.4 μA/cm2 under light illumination (AM 1.5 100 mW/cm2). The energy conversion efficiency and fill factor were found to be 3.4 × 10− 4% and 0.238 respectively. 相似文献