全文获取类型
收费全文 | 278篇 |
免费 | 15篇 |
专业分类
电工技术 | 8篇 |
综合类 | 2篇 |
化学工业 | 111篇 |
金属工艺 | 7篇 |
机械仪表 | 12篇 |
建筑科学 | 5篇 |
能源动力 | 9篇 |
轻工业 | 33篇 |
水利工程 | 1篇 |
石油天然气 | 2篇 |
无线电 | 20篇 |
一般工业技术 | 46篇 |
冶金工业 | 10篇 |
原子能技术 | 4篇 |
自动化技术 | 23篇 |
出版年
2023年 | 2篇 |
2022年 | 1篇 |
2021年 | 7篇 |
2020年 | 6篇 |
2019年 | 5篇 |
2018年 | 7篇 |
2017年 | 8篇 |
2016年 | 5篇 |
2015年 | 7篇 |
2014年 | 4篇 |
2013年 | 29篇 |
2012年 | 12篇 |
2011年 | 16篇 |
2010年 | 13篇 |
2009年 | 11篇 |
2008年 | 11篇 |
2007年 | 11篇 |
2006年 | 11篇 |
2005年 | 15篇 |
2004年 | 8篇 |
2003年 | 18篇 |
2002年 | 9篇 |
2001年 | 6篇 |
2000年 | 6篇 |
1999年 | 6篇 |
1998年 | 12篇 |
1997年 | 5篇 |
1996年 | 4篇 |
1995年 | 5篇 |
1994年 | 11篇 |
1993年 | 4篇 |
1992年 | 4篇 |
1991年 | 1篇 |
1987年 | 3篇 |
1985年 | 2篇 |
1984年 | 1篇 |
1982年 | 1篇 |
1981年 | 1篇 |
1980年 | 1篇 |
1977年 | 3篇 |
1976年 | 1篇 |
排序方式: 共有293条查询结果,搜索用时 15 毫秒
1.
Tadashi Hano Michiaki Matsumoto Takahisa Kawazu Takaaki Ohtake 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》1995,62(1):60-63
The extraction equilibria of various di- and tripeptides with di-2-ethylhexylphosphoric acid (D2EHPA) were studied at low pH values. The complex extracted to organic phase consisted of one molecule of peptide and two molecules of D2EHPA dimer. The extraction constants of the peptides correlated well with the distribution coefficients of peptides between 1-octanol and water, which is a measure of hydrophobicity. The permeation rates of peptides through an emulsion liquid membrane were examined by using D2EHPA as a carrier, Span 80 as an emulsifier and kerosene as a diluent. The rates varied considerably with peptide type, depending upon the hydrophobicity. 相似文献
2.
N,N'- Unsymmetrical dialkyl-3,4:9,10-perylenebis(dicarboximide)s (in which alkyl = methyl, ethyl, propyl, butyl, isobutyl, pentyl, hexyl and octyl) were prepared by the condensation of N-alkyl-3,4:9,10-perylene-tetracarboxylic monoanhydride monoimide with the appropriate alkyl-amines. The properties of these derivatives as pigments were tested and their thermal stability measured. 相似文献
3.
N′-Alkyl-N′-aryl-3,4:9,10-perylenebis(dicarboximide) (alkyl = isobutyl, pentyl, hexyl, octyl, etc.; aryl = phenyl, p-tolyl, p-methoxyphenyl, etc.) were prepared by the condensation of N-alkyl-3,4:9,10-perylene-tetracarboxylic monoanhydride monoimide with arylamines (aniline, p-toluidine, p-anisidine, o-phenylenediamine, etc.). The properties of these derivatives as pigments were tested, and also the thermal stability of 3,4:9,10-perylenebis(dicarboximide) derivatives was measured. 相似文献
4.
An ozone generator using a rotating electrode to improve ozone generation efficiency is proposed. The ozone generator electrode unit consists of a rotating electrode and fixed electrode. The rotating electrode has the grounded 36 pieces of tungsten wires fixed in parallel to the rotation axis on the rotating cylinder surface. A dielectric electrode is used as a fixed electrode located on the inside of the tube of the electrode unit. The width of the apparent discharge gap is 1mm. Alternating current with a frequency of 50 Hz is applied to the electrode unit. The rotation speed can be adjusted from 0 rpm to 1200 rpm by a variable speed motor. Oxygen gas is used as the material gas. Higher ozone concentration and higher ozone generation efficiency are obtained compared with that when the rotation speed is 0 rpm. The gas temperature is measured at the inlet and outlet of the ozone generator, and the rotation speed for the cooling effect is most effective at about 500 rpm. The maximum generation efficiency is estimated to be 61 g/kWh at 800 rpm, and this value is twice as large as in the case of 0 rpm. 相似文献
5.
6.
Development of flexible displays using back‐channel‐etched In–Sn–Zn–O thin‐film transistors and air‐stable inverted organic light‐emitting diodes 下载免费PDF全文
Mitsuru Nakata Genichi Motomura Yoshiki Nakajima Tatsuya Takei Hiroshi Tsuji Hirohiko Fukagawa Takahisa Shimizu Toshimitsu Tsuzuki Yoshihide Fujisaki Toshihiro Yamamoto 《Journal of the Society for Information Display》2016,24(1):3-11
We developed flexible displays using back‐channel‐etched In–Sn–Zn–O (ITZO) thin‐film transistors (TFTs) and air‐stable inverted organic light‐emitting diodes (iOLEDs). The TFTs fabricated on a polyimide film exhibited high mobility (32.9 cm2/Vs) and stability by utilization of a solution‐processed organic passivation layer. ITZO was also used as an electron injection layer (EIL) in the iOLEDs instead of conventional air‐sensitive materials. The iOLED with ITZO as an EIL exhibited higher efficiency and a lower driving voltage than that of conventional iOLEDs. Our approach of the simultaneous formation of ITZO film as both of a channel layer in TFTs and of an EIL in iOLEDs offers simple fabrication process. 相似文献
7.
Tetsuro Kobayashi Jeffrey Boase Tsutomu Suzuki Takahisa Suzuki 《Journal of Computer-Mediated Communication》2015,20(3):330-345
The tele‐cocooning hypothesis posits that mobile communication increases interaction with communication rich ties, while simultaneously weakening interaction with communication weak ties. In this study, we demonstrate how smartphones can be used to mitigate tele‐cocooning behavior by stimulating interaction with communication weak ties. Using a smartphone application to collect non‐identifying mobile communication log data, we conducted a field experiment with 193 Japanese participants. The treatment consisted of onscreen reminders designed to stimulate interaction with communication weak ties. The results indicate that the treatment promoted the activation of communication weak ties and the acquisition of information through those ties, suggesting that smartphones can be utilized to promote access to social capital. 相似文献
8.
Tajima T Takiguchi N Kato J Ikeda T Kuroda A Ohtake H 《Journal of Bioscience and Bioengineering》2003,96(2):149-153
The nematode Caenorhabditis elegans exhibits chemotaxis toward a wide variety of chemicals including water-soluble molecules and volatile organic compounds. We have previously discovered that C. elegans wild-type strain N2 is strongly attracted by cycloheximide which has long been known as a bitter tastant for humans and other mammals. We describe here the isolation and initial characterization of the first mutants which were defective specifically in their attraction to cycloheximide. In our screenings, we selected two mutants that were defective in chemotaxis to cycloheximide but normal in their attraction to NH4Cl and histidine. These mutants also avoided quinine hydrochloride, CuSO4 and high concentrations of NaCl similar to the wild-type strain N2. Furthermore, no observable defect was detected in their attraction to volatile odorants such as isoamyl alcohol and diacetyl. Dye-filling experiments suggested that they have no morphological defect in the sensory endings of the amphid neurons. 相似文献
9.
Lianqi Zhang Hideyuki Noguchi Decheng Li Takahisa Muta Xiaoqing Wang Masaki Yoshio Izumi Taniguchi 《Journal of power sources》2008
On the basis of extreme similarity between the triangle phase diagrams of LiNiO2–LiTiO2–Li[Li1/3Ti2/3]O2 and LiNiO2–LiMnO2–Li[Li1/3Mn2/3]O2, new Li–Ni–Ti–O series with a nominal composition of Li1+z/3Ni1/2−z/2Ti1/2+z/6O2 (0 ≤ z ≤ 0.5) was designed and attempted to prepare via a spray-drying method. XRD identified that new Li–Ni–Ti–O compounds had cubic rocksalt structure, in which Li, Ni and Ti were evenly distributed on the octahedral sites in cubic closely packed lattice of oxygen ions. They can be considered as the solid solution between cubic LiNi1/2Ti1/2O2 and Li[Li1/3Ti2/3]O2 (high temperature form). Charge–discharge tests showed that Li–Ni–Ti–O compounds with appropriate compositions could display a considerable capacity (more than 80 mAh g−1 for 0.2 ≤ z ≤ 0.27) at room temperature in the voltage range of 4.5–2.5 V and good electrochemical properties within respect to capacity (more than 150 mAh g−1 for 0 ≤ z ≤ 0.27), cycleability and rate capability at an elevated temperature of 50 °C. These suggest that the disordered cubic structure in some cases may function as a good host structure for intercalation/deintercalation of Li+. A preliminary electrochemical comparison between Li1+z/3Ni1/2−z/2Ti1/2+z/6O2 (0 ≤ z ≤ 0.5) and Li6/5Ni2/5Ti2/5O2 indicated that charge–discharge mechanism based on Ni redox at the voltage of >3.0 V behaved somewhat differently, that is, Ni could be reduced to +2 in Li1+z/3Ni1/2−z/2Ti1/2+z/6O2 while +3 in Li6/5Ni2/5Ti2/5O2. Reduction of Ti4+ at a plateau of around 2.3 V could be clearly detected in Li1+z/3Ni1/2−z/2Ti1/2+z/6O2 with 0.27 ≤ z ≤ 0.5 at 50 °C after a deep charge associated with charge compensation from oxygen ion during initial cycle. 相似文献
10.
Electrocodeposition of Sm and Co on a Cu substrate was investigated in a molten LiCl-KCl-SmCl3 (0.5 mol.%)-CoCl2 (0.1 mol.%) system at 723 K. Phase of the deposited Sm-Co alloys could be controlled by electrolysis potential. SmCo3 was formed on a Cu substrate by potentiostatic electrolysis in the potential range of 0.20-0.90 V (vs. Li+/Li). Sm2Co17 was obtained in the potential range of 0.90-1.50 V. 相似文献