首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   77篇
  免费   9篇
电工技术   14篇
化学工业   23篇
机械仪表   1篇
建筑科学   2篇
能源动力   2篇
轻工业   16篇
一般工业技术   11篇
冶金工业   1篇
自动化技术   16篇
  2018年   5篇
  2017年   4篇
  2016年   4篇
  2013年   25篇
  2012年   1篇
  2010年   2篇
  2008年   1篇
  2007年   1篇
  2006年   1篇
  2002年   1篇
  1999年   1篇
  1998年   1篇
  1997年   6篇
  1995年   1篇
  1994年   1篇
  1992年   1篇
  1990年   2篇
  1989年   1篇
  1988年   2篇
  1987年   4篇
  1986年   1篇
  1985年   4篇
  1983年   3篇
  1982年   2篇
  1980年   2篇
  1979年   1篇
  1977年   3篇
  1976年   2篇
  1972年   1篇
  1960年   2篇
排序方式: 共有86条查询结果,搜索用时 287 毫秒
41.
In a previous paper (Amemiya 1983) two sufficient conditions were introduced for the delay-independent stabilization of linear systems by means of state-variable feedback including no delays.

In this paper the concept of delay-independently upper or lower bound of decaying rate assignability (DIUDA or DILDA) are introduced and it is proved that the two conditions previously obtained are necessary and sufficient condition for DIUDA and necessary condition for DILDA of linear systems by means of state-variable feedback including no delays. The conditions obtained are also applicable to systems including time-varying delays.  相似文献   
42.
Distorted tetragonal YNbO4 crystallizes from an amorphous material prepared by the simultaneous hydrolysis of yttrium and niobium alkoxides. It can be preserved at room temperature by quenching and has a unit cell with α=0.5164 nm and c= I,0864 nm. The structure contains tetrahedral NbO4 groups.  相似文献   
43.
The major odor components of finely grated, raw garlic in the air of the human mouth have been studied. Immediately after garlic ingestion, tests of the mouth air of six subjects revealed two major peaks that were positively identified as being allyl mercaptan and diallyl disulfide; these findings are based on an evaluation of the fragment patterns of a GC-MS analysis and from the actual retention times of these authentic compounds. The allyl mercaptan level was higher than the level of diallyl disulfide, although both compounds smell like garlic. Our results suggest that after garlic ingestion, allyl mercaptan is the major garlic-smelling compound in human mouth air, and diallyl disulfide is secondary.  相似文献   
44.
Peptidic fractions which inhibit angiotensin I‐converting enzyme (ACE) were separated from peptic digests of soybean by ion exchange chromatography and gel filtration. Further separation of the peptidic fractions by ODS HPLC afforded active peptides, the amino add sequences of which were identified by Edman's procedure as: Ile‐Ata (inhibitory against ACE with an IC50of 153 μM), Tyr‐Leu‐Ala‐Gly‐Asn‐Gln (14 μM), Phe‐Phe‐Leu (37 μM), Ile‐Tyr‐Leu‐Leu (42 μM), and Val‐Met‐Asp‐Lys‐Pro‐Gln‐Gly (39 μM). The antihypertensive activity of the soybean peptides was also investigated. Peptide fractions (2.0 g/kg body weight, oral administration) markedly towered the blood pressure of spontaneously hypertensive rats (SHRs).  相似文献   
45.
For the demonstration of feasibility and loss‐reduction effect of the larger‐capacity amorphous core transformers (AMT), this paper proposed the support structure and design method of the iron‐loss reduced amorphous wound cores with a weight of 7 tons. We designed and manufactured 10 MVA single‐phase test model with the cores inserted in a support cage having structures of the stress‐buffered core support, the proof electromagnetic force from the windings, and the stray loss‐reducing shields. The 50%‐loaded total loss of the test model estimated from the calculated and measured results has been reduced by 35% compared with a conventional silicon‐steel core transformer (SST) with the same power capacity.  相似文献   
46.
A pulse‐assisted ionization discharge applied to a magnetohydrodynamic (MHD) generator is proposed as a technique to increase an electrical conductivity of working fluid. In this study, a periodic structure of output power in the MHD generator by using pulse‐assisted ionization discharge was evaluated. As a result, the discharge electrode length and the velocity of working fluid affect the discharge current distribution. The periodic structure of output power was observed in the several conditions. When the velocity of working fluid is roughly same as the sound speed, the periodic structure of output power was not observed.  相似文献   
47.
A method is proposed to produce hypoallergenic rice usable for patients with rice allergy. Newly harvested rice grains were dipped in carbonate (pH 9) containing glycerin monooleate and Actinase and then the mixture was exposed to a reduced pressure for degassing. The degassed mixture was incubated at 37°C for 24 hr to hydrolyze proteins. The process produced rice grains from which the major allergenic globulin was decomposed. The product was evaluated by the radioallergosorbent test (RAST), with the result that its RAST value suggested negative allergenicity in most cases. The product was clinically administered to 7 patients with atopic dermatitis and no allergic reaction was observed in 6 of the 7.  相似文献   
48.
This paper describes the ordering mechanisms observed in Li ferrite powder samples with different particle sizes and aggregation states, as well as in sintered pellets. Measurement of ordering rates in the powder samples and observation of chemically etched surfaces of partially ordered pellets indicate that the ordering proceeds by a nucleation-growth mechanism and that the ordering initiates at grain boundaries and prevails into the inner part of the grains. In powder samples, surfaces as well as grain boundaries contribute to the initiation of ordering but their temperature dependences are different. The activation energy of the ordering is calculated to be 192 kj/mol.  相似文献   
49.
Crystalline fine powders of LiAlO2 can be prepared by hydrolysis of metal alkoxides for application to the breeder blanket in nuclear fusion. The precipitates were fine crystalline particles of β-LiAlO2of ∼0.1-μm size under controlled conditions. The transformation from β- to γ-phase was confirmed at temperatures between 700° and 750°C. The microstructure of a sintered body at 1000°C consisted of homogeneous fine particles and pores suitable for the blanket material. A fully dense sintered body could be prepared at 1400°C.  相似文献   
50.
This paper describes variable magnetization machines, which are capable of varying the magnetization state (MS) of permanent magnets during operation. A pulse current on the stator windings creates a magnetic field on the rotor; this can be used to manipulate the MS of the rotor magnets. Regulating the MS according to the machine operating condition can reduce machine losses. A proof‐of‐principle machine was designed and fabricated. A series of experiments was conducted to evaluate the torque–speed envelope and efficiency contours of the fabricated machine. A full‐scale machine was then designed with a modified magnetic circuit for application to an electric vehicle and evaluated using finite element analysis. A control strategy for the MS during machine operation is proposed, and the losses during a driving cycle with the strategy were evaluated.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号