全文获取类型
收费全文 | 675篇 |
免费 | 14篇 |
专业分类
电工技术 | 45篇 |
化学工业 | 230篇 |
金属工艺 | 22篇 |
机械仪表 | 23篇 |
建筑科学 | 11篇 |
能源动力 | 19篇 |
轻工业 | 19篇 |
无线电 | 41篇 |
一般工业技术 | 115篇 |
冶金工业 | 28篇 |
原子能技术 | 22篇 |
自动化技术 | 114篇 |
出版年
2023年 | 5篇 |
2022年 | 7篇 |
2021年 | 5篇 |
2020年 | 7篇 |
2019年 | 6篇 |
2018年 | 13篇 |
2017年 | 8篇 |
2016年 | 13篇 |
2015年 | 10篇 |
2014年 | 24篇 |
2013年 | 32篇 |
2012年 | 27篇 |
2011年 | 39篇 |
2010年 | 24篇 |
2009年 | 42篇 |
2008年 | 57篇 |
2007年 | 36篇 |
2006年 | 21篇 |
2005年 | 29篇 |
2004年 | 20篇 |
2003年 | 12篇 |
2002年 | 25篇 |
2001年 | 10篇 |
2000年 | 12篇 |
1999年 | 11篇 |
1998年 | 20篇 |
1997年 | 12篇 |
1996年 | 21篇 |
1995年 | 9篇 |
1994年 | 13篇 |
1993年 | 13篇 |
1992年 | 13篇 |
1991年 | 7篇 |
1990年 | 11篇 |
1989年 | 6篇 |
1988年 | 6篇 |
1987年 | 5篇 |
1986年 | 4篇 |
1985年 | 8篇 |
1984年 | 6篇 |
1983年 | 8篇 |
1979年 | 2篇 |
1978年 | 2篇 |
1977年 | 6篇 |
1976年 | 13篇 |
1973年 | 1篇 |
1972年 | 2篇 |
1971年 | 1篇 |
1968年 | 1篇 |
1967年 | 1篇 |
排序方式: 共有689条查询结果,搜索用时 15 毫秒
51.
Kittipan Pongmorakot Shoichi Nambu Toshihiko Koseki 《Science & Technology of Welding & Joining》2018,23(4):344-350
Solid-state bonding between ultralow-carbon steel and pure nickel was conducted by hot pressing with various compressive strain ranging from 5 to 15% and subsequent isothermal holding at 923?K. It was found that the interfacial strength of contact area is accounted for by the evolution of the intrinsic strength of the interface and the amount of plastic energy dissipation at the crack tip during interface fracture. The compression induces severe deformation around the interface and consequently inhibits the plastic energy dissipation during interface fracture. In the first stage of isothermal holding, the residual strain around the interface on the steel side is reduced by recovery process, which concurrently decreases in the yield stress of the area adjacent to the interface. This promotes plastic energy dissipation of the area, leading to a significant increase in interfacial strength in the first stage. 相似文献
52.
Kenji Shiota Masaki Takaoka Shuji Yamaguchi Kazuyuki Oshita 《Drying Technology》2015,33(11):1286-1294
Because fine particulate matter ≤2.5 µm in diameter (PM2.5) causes health problems, PM2.5 emissions are of concern. However, little research on stationary sources has been conducted. To determine the concentration and filtration behavior of PM2.5, dust was collected from five fluid-bed sewage sludge incinerators (SSIs) sorted by particle size using cascade impactors. The average PM2.5 concentration was 0.00014–4.8 mg/Nm3. The total estimated amount of PM2.5 emissions from the SSIs for all plants in Japan was 0.96–8.9 tons/year. Since the SSIs with dry Electrostatic Precipitators (EP) contributed 75–99% of the total emissions, replacing dry EPs with bag filters would significantly reduce the PM2.5 emissions from SSI. 相似文献
53.
Yuichi Shimauchi Sachiko Ode Tsutomu Yamazaki Yuta Matsushima Kazuyuki Maeda 《Journal of Porous Materials》2010,17(3):305-312
A new vapor phase transport (VPT) technique to prepare an inverse silica replica of an ordered mesoporous carbon was developed.
Tetraethyl orthosilicate (TEOS) was infiltrated in mesoporous carbon CMK-3 as the hard template at 180 °C for 48 h under an
autogenous pressure in an autoclave in the presence of water. The samples obtained by removal of CMK-3 retained structural
regularity of CMK-3 with little shrinkage of framework, which were characterized by SAXRD, N2 adsorption, TG-DTA, and SEM. Influence of preparation temperature on the loading amount of silica was investigated. The multi-step
replication process was monitored by characterizing the replicated materials as well as intermediate composites. 相似文献
54.
Effects of rice straw returning methods on N<Subscript>2</Subscript>O emission during wheat-growing season 总被引:1,自引:0,他引:1
Erdeng Ma Guangbin Zhang Jing Ma Hua Xu Zucong Cai Kazuyuki Yagi 《Nutrient Cycling in Agroecosystems》2010,88(3):463-469
A field experiment was conducted in Jurong of Nanjing, Jiangsu Province, China from 2006 to 2008 to investigate N2O emission during the wheat-growing season as affected by various rice straw returning methods prior to wheat cultivation.
The study was designed to have four treatments: no rice straw applied (CK), rice straw burnt in situ (RB), rice straw evenly
incorporated into the topsoil (RI), rice straw evenly spread over the field as mulch (RM). Results showed that N2O emission was decreased by 24–29% in Treatment RB and by 3–18% in Treatment RI, but increased by 15–39% in Treatment RM,
compared with that in Treatment CK. The contents of soil total C and N at wheat harvest were significantly increased by 7–13%
and by 8–12% in Treatment RI, respectively, compared with that in Treatment CK. The wheat grain yield in Treatment RI was
1.0–1.2 times that in the Treatment CK. Based on these results, the best management practice of returning rice straw to the
soil prior to wheat cultivation is evenly incorporating rice straw into the topsoil, as the method tended to reduce N2O emission during the wheat-growing season and increase wheat yield and soil fertility. 相似文献
55.
Tatsuhiko Matsumoto Satoru Kubota Yuta Kubota Kenta Imabayashi Kazuyuki Kishimoto Seiichi Goshi Shigeki Imai Youichi Igarashi Shuichi Haga Takehiro Nakatsue 《Journal of the Society for Information Display》2011,19(11):813-820
Abstract— To understand actual viewing conditions at home is important for TV design. And the preferred luminance level of LCD TVs under actual viewing conditions is also important in order to obtain both good picture quality and low power consumption. The actual viewing conditions of households and the preferred luminance levels was investigated. In a field test of 83 households, the display luminance, screen illuminance, and viewing locations were measured on site. In laboratory experiments, young and elderly subjects adjusted the luminance of an LCD‐TV screen to their preferred levels under different screen illuminance levels, angular screen sizes, and average luminance levels (ALL) of the images. As a result, two equations, which represent the preferred luminance level of LCD‐TV screens corresponding to different viewing conditions for young and elderly subjects were obtained. When the ALL of the images was 25% and the screen illuminance and angular screen size were set at 100 lx and 20°, respectively, the preferred luminance was 1 60 cd/m2 for the young subjects and 248 cd/m2 for the elderly subjects. By using the setting of the preferred luminance of an LCD TV under actual viewing conditions, it is possible to conserve energy consumption. 相似文献
56.
Nambu H. Kanetani K. Idei Y. Masuda T. Higeta K. Ohayashi M. Usami M. Yamaguchi K. Kikuchi T. Ikeda T. Ohhata K. Kusunoki T. Homma N. 《Solid-State Circuits, IEEE Journal of》1995,30(4):491-499
An ultrahigh-speed 72-kb ECL-CMOS RAM macro for a 1-Mb SRAM with 0.65-ns address-access time, 0.80-ns write-pulse width, and 30.24-μm 2 memory cells has been developed using 0.3-μm BiCMOS technology. Two key techniques for achieving ultrahigh speed are an ECL decoder/driver circuit with a BiCMOS inverter and a write-pulse generator with a replica memory cell. These circuit techniques can reduce access time and write-pulse width of the 72-kb RAM macro to 71% and 58% of those of RAM macros with conventional circuits. In order to reduce crosstalk noise for CMOS memory-cell arrays driven at extremely high speeds, a twisted bit-line structure with a normally on MOS equalizer is proposed. These techniques are especially useful for realizing ultrahigh-speed, high-density SRAM's, which have been used as cache and control storages in mainframe computers 相似文献
57.
Hiroki Takahashi Takahiro Tomita Hiroyuki Takahashi Yoshikazu Mizuguchi Yoshihiko Takano Satoshi Nakano Kazuyuki Matsubayashi Yoshiya Uwatoko 《Science and Technology of Advanced Materials》2012,13(5)
The superconducting transition temperature, Tc, in iron-based solids can be enhanced by applied pressure: Tc increases from 8 to 37 K for the 11-type FeSe when the pressure is raised from 0 to 4 GPa. High-pressure studies can elucidate the mechanism of superconductivity in such novel materials. In this paper, we present a high-pressure study of Fe(Se1−xTex) and Fe(Se1−xSx). In the case of Fe(Se1−xTex), the maximum Tc under high pressure did not exceed the Tc of FeSe, which can be attributed to the structural transition to the monoclinic phase. For Fe(Se1−xSx) (0 < x < 0.3), Tc exhibited a significant increase with pressure; however, the maximum Tc under high pressure did not exceed the Tc of FeSe. This may be due to the disorder induced by substituting S for Se, which is similar to the pressure effect on Tc for the 1111-type superconductor Ca(Fe1−xCox)AsF. The Tc of Fe(Se1−xSx) showed a complex behavior below 1 GPa, first decreasing and then increasing with increasing pressure. From high-pressure x-ray diffraction measurements, the Tc (P) curve was correlated with the local structural parameter. 相似文献
58.
Shoichi Nambu 《Water research》1971,5(12):1127-1134
A mathematical model based on the equilibrium of BOD materials in the activated sludge process was developed. When the excess sludge is negligibly small and the BOD concentration of the influent is given, the BOD concentration of the activated sludge or mixed liquor and the efficiency of BOD removal are determined only by the aeration period. Moreover, it was verified mathematically that the performance of the activated sludge process became unstable with decrease of the return sludge ratio and the aeration period. 相似文献
59.
Danilo P. Mandic Su Lee Goh Kazuyuki Aihara 《Journal of Signal Processing Systems》2007,48(1-2):99-108
A sequential data fusion approach via higher dimensional vector spaces is introduced. This is achieved by making use of the representation of directional signals within the field of complex numbers $C$ . The concept of data fusion is next introduced and the place of the proposed approach within that framework is identified. The benefits of such an approach are illustrated and a range of possible applications is shown. The concept introduced is supported by a real world case study which focuses on simultaneous forecasting of wind speed and direction. The architectures and learning algorithms which support this concept are introduced and their distributed sequential fusion nature is highlighted. 相似文献
60.
Yoshiyuki Sugahara Ken-Ichi Sugimoto Kazuyuki Kuroda Chuzo Kato 《Journal of the American Ceramic Society》1988,71(7):325-C
Both silicon carbide and aluminum silicon carbide have simultaneously been obtained directly from naturally occurring aluminosilicate by carbothermal reduction for the first time. A precursor of a montmorillonite–polyacrylonitrile (PAN) intercalation compound was heated at 1700°C in Ar. For comparison, montmorillonite–carbon mixtures were similarly heated. α-SiC, β-SiC, and Al4 Si2 C5 formed from the montmorillonite–PAN intercalation compound. Mainly α-Al4 SiC4 was obtained with ternary carbides from the montmorillonite–carbon mixtures in addition to a large amount of β-SiC. Hence, aluminum silicon carbide formation was affected by the mixing condition of the starting materials. 相似文献