全文获取类型
收费全文 | 11881篇 |
免费 | 2615篇 |
国内免费 | 370篇 |
专业分类
电工技术 | 30篇 |
综合类 | 657篇 |
化学工业 | 2024篇 |
金属工艺 | 857篇 |
机械仪表 | 145篇 |
建筑科学 | 557篇 |
矿业工程 | 2759篇 |
能源动力 | 64篇 |
轻工业 | 395篇 |
水利工程 | 54篇 |
石油天然气 | 69篇 |
武器工业 | 3篇 |
无线电 | 414篇 |
一般工业技术 | 1141篇 |
冶金工业 | 5490篇 |
原子能技术 | 125篇 |
自动化技术 | 82篇 |
出版年
2024年 | 34篇 |
2023年 | 214篇 |
2022年 | 378篇 |
2021年 | 442篇 |
2020年 | 503篇 |
2019年 | 405篇 |
2018年 | 427篇 |
2017年 | 530篇 |
2016年 | 688篇 |
2015年 | 603篇 |
2014年 | 806篇 |
2013年 | 945篇 |
2012年 | 900篇 |
2011年 | 892篇 |
2010年 | 665篇 |
2009年 | 605篇 |
2008年 | 503篇 |
2007年 | 614篇 |
2006年 | 511篇 |
2005年 | 463篇 |
2004年 | 402篇 |
2003年 | 429篇 |
2002年 | 338篇 |
2001年 | 362篇 |
2000年 | 332篇 |
1999年 | 312篇 |
1998年 | 254篇 |
1997年 | 191篇 |
1996年 | 172篇 |
1995年 | 159篇 |
1994年 | 160篇 |
1993年 | 135篇 |
1992年 | 107篇 |
1991年 | 113篇 |
1990年 | 78篇 |
1989年 | 92篇 |
1988年 | 35篇 |
1987年 | 27篇 |
1986年 | 9篇 |
1985年 | 10篇 |
1984年 | 6篇 |
1983年 | 2篇 |
1982年 | 4篇 |
1981年 | 2篇 |
1980年 | 2篇 |
1979年 | 2篇 |
1978年 | 1篇 |
1974年 | 1篇 |
1951年 | 1篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
《Advanced Powder Technology》2022,33(11):103833
Eliminating the gold preg-robbing effect of carbonaceous matter in carbonaceous gold ores is crucial for gold leaching. In this study, suspension oxidation roasting was proposed to accelerate the decarbonization of carbonaceous gold ore. The characteristics of oxidation reaction process and gas release were analyzed by TG-DTA-FTIR. The phase transformation and microstructure evolution of samples during roasting were analyzed by XRD, SEM and BET. The results show that the gold preg-robbing effect was eliminated after the gasification of carbonaceous matter, and the CaO generated by decomposition of carbonates can effectively capture the SO2. After roasting for 75 min at 650 °C in a 20% O2 atmosphere, the total carbon removal rate reached 99.42%, the distribution of exposed gold increased from 28.85% to 77.10% and the gold leaching efficiency increased from 4.55% to 84.83%. In addition, about 70% sulfur was mainly fixed in the roasted products in the form of sulfate. Therefore, the suspension oxidation roasting process is an efficient and clean pretreatment method for carbonaceous gold ores. 相似文献
2.
3.
Rong Zhu Juan Li Lisen Lin Jibin Song Huanghao Yang 《Advanced functional materials》2021,31(10):2005709
Plasmonic gold nanocrystal represents plasmonic metal nanomaterials, and has a variety of unique and beneficial properties, such as optical signal enhancement, catalytic activity, and photothermal properties tuned by local temperature, which are useful in physical, chemical, and biological applications. In addition, the inherent properties of predictable programmability, sequence specificity, and structural plasticity provide DNA nanostructures with precise controllability, spatial addressability, and targeting recognition, serving as ideal ligands to link or position building blocks during the self-assembly process. Self-assembly is a common technique for the organization of prefabricated and discrete nanoparticle blocks for the construction of extremely sophisticated nanocomposites. To this end, the integration of DNA nanotechnology with Au nanomaterials, followed by assembly of DNA-functionalized Au nanomaterials can form novel functional Au nanomaterials that are difficult to obtain through conventional methods. Here, recent progress in DNA-assembled Au nanostructures of various shapes is summarized, and their functions are discussed. The fabrication strategies that employ DNA for the self-assembly of Au nanostructures, including dimers, tetramers, satellites, nanochains, and other nanostructures with more complex geometric configurations are first described. Then, the characteristic optical properties and applications of biosensing, bioimaging, drug delivery, and therapy are discussed. Finally, the remaining challenges and prospects are elucidated. 相似文献
4.
5.
Xiang-feng KONG Xing-xing JIANG Sheng-guo XUE Ling HUANG William HARTLEY Chuan WU Xiao-fei LI 《中国有色金属学会会刊》2018,28(3):534-541
Bauxite residue, a highly saline solid waste produced from digestion of bauxite for alumina production, is hazardous to the environment and restricts vegetation establishment in bauxite residue disposal areas. A novel water leaching process proposed here was used to investigate the dynamic migration and vertical distribution of saline ions in bauxite residue. The results show that water leaching significantly reduced the salinity of bauxite residue, leaching both saline cations Na+, K+, Ca2+ and anions CO2?3, SO2?4, HCO?3. Na+ and K+ migrated from 40–50 to 20–30 cm of the column, presenting a high migration capacity. The migration capacity of Ca2+ was lower and accumulated at 30–40 cm of the column. CO2?3 initially distributed at 20–30 cm of the column, subsequently transported to 30–40 cm of the column, and finally returned to 20–30 cm of the column along with evaporation. SO2?4 was originally distributed at 40–50 cm, but finally migrated to 20–30 cm of the column. Nevertheless, HCO?3 remained at the bottom of the column, and its migratory was less affected by evaporation. 相似文献
6.
建立了一种快速定量检测水产品鱼和虾中苯巴比妥残留的胶体金免疫层析方法。采用胶体金纳米粒标记苯巴比妥单克隆抗体,研究了胶体金免疫层析条件如标记体系p H值、标记抗体浓度、检测T线包被原浓度、质控C线羊抗鼠Ig G浓度、样品前处理方法等对胶体金灵敏度的影响,并借助胶体金试纸条读数仪进行定量检测。结果表明:方法检出限为0.07 ng/mL,线性范围0.08~0.94ng/m L,裸眼消线值(cut-off值)为10.0 ng/mL。方法特异性良好,与巴比妥、戊巴比妥、异戊巴比妥三种结构类似物交叉反应率小于10%。选择罗非鱼、草鱼、鲈鱼和虾进行添加回收试验,样品回收率在73.50%~114.17%之间,相对标准偏差小于15%,且结果与UPLC-MS/MS法一致。该方法具有准确、灵敏、简便、快速等特点,非常适用于水产品鱼和虾中苯巴比妥残留现场快速筛查。 相似文献
7.
Ximei Zhao Matthias Rudolph Abdullah M. Asiri A. Stephen K. Hashmi 《Frontiers of Chemical Science and Engineering》2020,14(3):317
This review summarizes recent advances in the field of gold-catalyzed synthesis of pharmaceutically relevant aza-heterocycles via in situ generated α-imino gold carbene complexes as intermediates. 相似文献
8.
针对湖南柿竹园铋精矿火法冶炼过程中存在的成本高、低浓度SO2和散烟排放污染环境、有价金属综合回收率低等问题, 以柿竹园铋精矿为原料, 提出了加压氧化氨浸分离铋与铜、硫的新工艺, 研究了氨水加入量、浸出温度、浸出时间、浸出压力及浸出液固比等因素对铜、硫、铋浸出率的影响。在氨水用量1.8 mL/g铋精矿、液固比4∶1、釜压2.8 MPa、浸出温度160 ℃、浸出时间5 h、搅拌速度600 r/min的优化工艺条件下, 铜、硫浸出率分别达93.57%和92.87%, 铋不浸出并以氧化铋形态全部入渣, 实现了铜、硫与铋的高效分离。 相似文献
9.
福建某斑岩型金矿品位低、规模大,金主要以自然金形式存在,可见金的粒度较粗,为高效利用该低品位金矿,开展新型浸金剂金蝉全泥浸出试验和柱浸试验,结果表明:全泥浸出在磨矿细度为-0.074 mm占80%、矿浆浓度25%、加石灰调pH 值11.0左右、初始金蝉浓度为500 mg/L和过程中控制金蝉浓度不小于300 mg/L条件下浸出20 h,金的浸出率为93.43%,金蝉耗量为1.02 kg/t;柱浸在矿石粒度为-30 mm条件下喷淋浸出23天,金累计浸出率和金蝉累计耗量分别为86.54%和1.22 kg/t。 相似文献
10.