全文获取类型
收费全文 | 507篇 |
免费 | 48篇 |
国内免费 | 46篇 |
专业分类
电工技术 | 46篇 |
综合类 | 24篇 |
化学工业 | 39篇 |
金属工艺 | 14篇 |
机械仪表 | 15篇 |
建筑科学 | 13篇 |
矿业工程 | 6篇 |
能源动力 | 17篇 |
轻工业 | 25篇 |
水利工程 | 2篇 |
石油天然气 | 33篇 |
武器工业 | 1篇 |
无线电 | 200篇 |
一般工业技术 | 20篇 |
冶金工业 | 3篇 |
原子能技术 | 3篇 |
自动化技术 | 140篇 |
出版年
2024年 | 3篇 |
2023年 | 2篇 |
2022年 | 5篇 |
2021年 | 5篇 |
2020年 | 10篇 |
2019年 | 4篇 |
2018年 | 17篇 |
2017年 | 11篇 |
2016年 | 23篇 |
2015年 | 19篇 |
2014年 | 25篇 |
2013年 | 23篇 |
2012年 | 35篇 |
2011年 | 41篇 |
2010年 | 44篇 |
2009年 | 32篇 |
2008年 | 48篇 |
2007年 | 43篇 |
2006年 | 50篇 |
2005年 | 41篇 |
2004年 | 29篇 |
2003年 | 28篇 |
2002年 | 20篇 |
2001年 | 17篇 |
2000年 | 8篇 |
1999年 | 7篇 |
1998年 | 7篇 |
1997年 | 2篇 |
1995年 | 1篇 |
1994年 | 1篇 |
排序方式: 共有601条查询结果,搜索用时 12 毫秒
81.
Technical and Economical Aspects of Current Thermal Barrier Coating Systems for Gas Turbine Engines by Thermal Spray and EBPVD: A Review 总被引:3,自引:1,他引:3
Albert Feuerstein James Knapp Thomas Taylor Adil Ashary Ann Bolcavage Neil Hitchman 《Journal of Thermal Spray Technology》2008,17(2):199-213
The most advanced thermal barrier coating (TBC) systems for aircraft engine and power generation hot section components consist
of electron beam physical vapor deposition (EBPVD) applied yttria-stabilized zirconia and platinum modified diffusion aluminide
bond coating. Thermally sprayed ceramic and MCrAlY bond coatings, however, are still used extensively for combustors and power
generation blades and vanes. This article highlights the key features of plasma spray and HVOF, diffusion aluminizing, and
EBPVD coating processes. The coating characteristics of thermally sprayed MCrAlY bond coat as well as low density and dense
vertically cracked (DVC) Zircoat TBC are described. Essential features of a typical EBPVD TBC coating system, consisting of
a diffusion aluminide and a columnar TBC, are also presented. The major coating cost elements such as material, equipment
and processing are explained for the different technologies, with a performance and cost comparison given for selected examples. 相似文献
82.
Li Wang Jie Zhang Zhentao Mi 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2006,81(4):710-712
The ammoximation of methyl ethyl ketone and hydrogen peroxide to form methyl ethyl ketoxime was studied over zeolites (TS‐1) in the temperature range 308–373 K. The reaction was carried out in a batch autoclave at autogenous pressure. The conversion of methyl ethyl ketone and the selectivity to methyl ethyl ketoxime can reach 99% and approximately 100%, respectively, and the by‐products were the small amounts of corresponding methyl ethyl ketazine and trace amounts of unidentified compounds. Important factors were the reaction temperature, solvents and slow addition of hydrogen peroxide. The molar ratio of NH3 to ketone had no significant effect on the conversion of methyl ethyl ketone, but increase in the ratio of NH3 to ketone had a beneficial effect on selectivity. Copyright © 2006 Society of Chemical Industry 相似文献
83.
84.
20CrMnTiH(TS)钢冶金流程为60 t 顶底复吹转炉-LF-VD-150 mm×150 mm方坯连铸。钢厂20CrMnTiH(TS)钢夹杂物一次检验不合格率达2.0%,主要为B类(复合钙铝酸盐+镁铝尖晶石,以及部分三氧化二铝)和D类夹杂(钙铝酸盐,部分为复合钙铝酸盐+镁铝尖晶石+氮化钛),尺寸>20μm。通过采用低磷铁水和优质废钢,转炉终点[C]≥0.09%,转炉出钢加40 kg硅钙和40 kg钢芯铝替代原只加80 kg钢芯铝预脱氧,LF精炼采用SiC70替代SiC45进行扩散脱氧,VD后喂Ti线,保证精炼终渣碱度为3.0,控制连铸时钢包余钢量>2 t 等工艺措施使T[O]从12×10-6降至8×10-6,一次夹杂物检验不合格率下降至0.5%。 相似文献
85.
Felicia N. Ihunegbo Michael Madsen Jens Bo Holm-Nielsen 《Chemometrics and Intelligent Laboratory Systems》2012,110(1):135-143
Dry matter is an important process control parameter in the bioconversion application field. Acoustic chemometrics, as a Process Analytical Technology (PAT) modality for quantitative characterisation of dry matter in complex bioslurry systems (biogas fermentation), has not been successful despite several earlier dedicated attempts. A full-scale feasibility study based on standard addition experiments involving natural plant biomass was conducted using multivariate calibration (Partial Least Squares Regression, PLS-R) of acoustic signatures against dry matter content (total solids, TS). Prediction performance of the optimised process implementation was evaluated using independent test set validation, with estimates of accuracy (slope of predicted vs. reference values) and precision (squared correlation coefficient, r2) of 0.94 and 0.97 respectively, with RMSEP of 0.32% w/w (RMSEPrel = 3.86%) in the range of 5.8-10.8% w/w dry matter. Based on these excellent prediction performance measures, it is concluded that acoustic chemometrics has come of age as a full grown PAT approach for on-line monitoring of dry matter (TS) in complex bioslurry, with a promising application potential in other biomass processing industries as well. 相似文献
86.
87.
采用双通道多极旋转变压器和AD2S83构成的测角系统可以实现角位置和角速度的高精度动态测量。该测角系统采用单片机实现角位置的动态监控,使用CPLD完成了AD2S83与DSP通信的接口逻辑设计,并采用DSP实现双通道角位置粗精耦合及测速算法。 相似文献
88.
汽车零部件是汽车工业的基础,其质量是影响汽车主机厂质量和成本的重要因素。在现有ISO/TS16949标准的基础上,结合工作经历,提出一种评价方法,来提高汽车零部件企业的控制管理能力,希望能给汽车企业管理者提供参考。 相似文献
89.
针对传统硬件测试软件的弊端,文章提出一种便携式视频数据逻辑分析存储器的设计方法,这种分析存储器能够针对网络多媒体数据进行采集、分析和存储等操作。在不影响网络正常传输的前提下,针对TS流进行采集、存储和分析。由于多媒体数据网络传输具有数据量大、网络带宽占用量大等特点,因此设计中根据系统结构需要,设计SDR SDRAM存储器控制器,采用分层状态机的设计模式,可以对结构较大的网络数据包或是大量高速传输中的数据进行突发存储操作。测试结果表明系统工作稳定,数据处理速度快,精度可达纳秒级,满足系统设计要求。 相似文献
90.