全文获取类型
收费全文 | 2074篇 |
免费 | 132篇 |
国内免费 | 288篇 |
专业分类
电工技术 | 22篇 |
综合类 | 42篇 |
化学工业 | 195篇 |
金属工艺 | 47篇 |
机械仪表 | 186篇 |
建筑科学 | 143篇 |
矿业工程 | 120篇 |
能源动力 | 189篇 |
轻工业 | 379篇 |
水利工程 | 102篇 |
石油天然气 | 70篇 |
武器工业 | 2篇 |
无线电 | 57篇 |
一般工业技术 | 501篇 |
冶金工业 | 20篇 |
原子能技术 | 8篇 |
自动化技术 | 411篇 |
出版年
2024年 | 2篇 |
2023年 | 10篇 |
2022年 | 13篇 |
2021年 | 18篇 |
2020年 | 78篇 |
2019年 | 81篇 |
2018年 | 156篇 |
2017年 | 148篇 |
2016年 | 103篇 |
2015年 | 120篇 |
2014年 | 79篇 |
2013年 | 56篇 |
2012年 | 171篇 |
2011年 | 171篇 |
2010年 | 100篇 |
2009年 | 62篇 |
2008年 | 224篇 |
2007年 | 213篇 |
2006年 | 98篇 |
2005年 | 93篇 |
2004年 | 72篇 |
2003年 | 68篇 |
2002年 | 74篇 |
2001年 | 82篇 |
2000年 | 63篇 |
1999年 | 42篇 |
1998年 | 22篇 |
1997年 | 19篇 |
1996年 | 12篇 |
1995年 | 5篇 |
1994年 | 3篇 |
1993年 | 3篇 |
1992年 | 2篇 |
1991年 | 1篇 |
1990年 | 3篇 |
1989年 | 3篇 |
1988年 | 1篇 |
1987年 | 2篇 |
1986年 | 3篇 |
1985年 | 1篇 |
1984年 | 1篇 |
1983年 | 5篇 |
1982年 | 2篇 |
1981年 | 1篇 |
1980年 | 2篇 |
1979年 | 1篇 |
1974年 | 2篇 |
1973年 | 1篇 |
1965年 | 1篇 |
1964年 | 1篇 |
排序方式: 共有2494条查询结果,搜索用时 15 毫秒
1.
11 January 2007, Beijing - PetroChina Company Limited (PetroChina) signed a framework agreement with the State Forestry Administration (SFA) on the development of forest bin-fuel and officially kicked off the construction of the first batch of forest bio-fuel tree breeding bases in Yunnan and Sichuan, marking a substantial step forward in the cooperation of forest bio-fuel development between the two parties. 相似文献
2.
Chinese emergency services carried out their largest ever exercise in early June to tackle an oil spill in the Bohai Sea to test their ability to protect the ocean environment. The drill involved a scenario in which a -ton oil tanker exploded spilt tons of oil.Soon after the oil tanker Tianpeng "exploded" a fireboat arrived to fight the fire a helicopter hovered above to spread chemicals to control oil spill followed by more vessels another helicopter.…… 《中国油气》2007,14(2):18-18
Chinese emergency services carried out their largest ever exercise in early June to tackle an oil spill in the Bohai Sea to test their ability to protect the ocean environment. The drill involved a scenario in which a 10,000-ton oil tanker exploded and spilt 500 tons of oil. Soon after the oil tanker Tianpeng "exploded", a fireboat arrived to fight the fire and a helicopter hovered above to spread chemicals to control oil spill, followed by more vessels and another helicopter. 相似文献
3.
ture a 《网络安全技术与应用》2003,(5)
2Many Cucurbitaceae plants were known to be Chinese medicine herbs and contain ribosome-inactivating proteins (RIP), a group of toxic proteins that have been proposed and demonstrated to play potential use as toxins in the therapy of a variety of human tumors and viruses inc 相似文献
4.
提出利用故障生成的电流暂态分量进行故障定位的思想。通过与方向行波测距进行比较,指出两者在利用行波表示的时间-距离对应信息上的一致性。与传统的电流行波测距法相比,该算法无需相邻健全线路的电流,从而具有更 好的适应系统运行方式的能力,并节省了测距装置的模拟和数字输入通道。仿真试验表明, 在合适的小波滤波器和小波分解算法的作用下,暂态测距与利用方向行波测距的精度基本相 同。其在测距精度上同样不受故障类型、接地电阻、线路长度、采样率、系统运行方式的影响,具有良好的波头定位能力。 相似文献
5.
On August th Pu Changcheng Deputy Director of AQSIQ addressing a national press conference on cake moon cake quality safety market access reported that as of the end of July cake moon cake enterprises had gained market access qualifications had obtained food production licenses.…… 《中国标准化(英文版)》2007,24(6):33
On August 29th, Pu Changcheng, Deputy Director of AQSIQ, addressing a national press conference on cake and moon cake quality safety market access, reported that as of the end of July 2007, 761cake and moon cake enterprises had gained market access qualifications and had obtained food production licenses. 相似文献
6.
On August st the General Administration of Quality Supervision Inspection Quarantine 《中国标准化(英文版)》2007,23(5):30
On August 1st, the General Administration of Quality Supervision, Inspection and Quarantine (AQSIQ) convened a conference to transmit the spirit of national quality work and study an important speech regarding standards from Wen Jiabao,Premier of the State Council. 相似文献
7.
Ms. Chen Zhili a State Councilor expressed on the Glooal Forum on Intellectual Property Rights Protection Innovation that a plan on the preparation of China's strategy on intellectual property rights would be issued put into implcmentation this year in an effort to jointly create a harmonious environment in which dialogue instead of confrontation will prevail.. At the forum Mr.…… 《中国标准化(英文版)》2007,(4):38
Ms. Chen Zhili, a State Councilor,expressed on the Glooal Forum on Intellectual Property Rights Protection and Innovation that a plan on the preparation of China's strategy on intellectual property rights would be issued and put into implcmentation this year, in an effort to jointly create a harmonious environment in which dialogue instead of confrontation will prevail.. At the forum, Mr. 相似文献
8.
December th is the fifth anniversary of China's entry into WTO. Over the past five years what AQSIQ has done in implementing the obligations enjoying the rights as a member of WTO? How's the performance? Facing with the current complicated barrier of technology trade worldwide how will China reply to it? For these questions reporters have made a special interview with Li Changjiang Minister of AQSIQ.…… 《中国标准化(英文版)》2007,(1):2-7
December 11th, 2006 is the fifth anniversary of China's entry into WTO. Over the past five years, what AQSIQ has done in implementing the obligations and enjoying the rights as a member of WTO? How's the performance? Facing with the current complicated barrier of technology trade worldwide, how will China reply to it? For these questions, reporters have made a special interview with Li Changjiang, Minister of AQSIQ. 相似文献
9.
亚速钢公司生产名牌品种和尺寸品种众多的K52到K60强度级别大直径天然气输送管用厚板钢材,供给乌克兰和俄罗斯企业一哈尔崔兹斯克钢管厂、维克苏钢铁厂、伏尔加钢管厂和其它厂,而同时强度级别从X42到X70,主要提供给国外远方的用户一印度、墨西哥、土耳其、东南亚。 相似文献
10.