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61.
62.
Prof. Minoru Yoshimoto Satoshi Kobirata Wataru Sakamoto Hidenobu Aizawa Shigeru Kurosawa 《仪器科学与技术》2013,41(5):495-505
Abstract The present work reports the new characteristics of the immersion‐angle dependence of the resonant‐frequency shift (ΔF) of the one‐face sealed quartz crystal microbalance (QCM) in three types of Newtonian liquids, i.e., sucrose, glucose, and glycerol solutions. Below some 1.80×10?2 g cm?2 · s?1/2, the ΔF values are dependent on the immersion angles in all solutions. However, we have found that the transition phenomenon of ΔF occurs between 1.78×10?2 and 4.80×10?2 g · cm?2 · s?1/2 in the sucrose solution, between 1.75×10?2 and 4.34×10?2 g · cm?2 · s?1/2 in the glucose solution and between 1.83×10?2 and 3.03×10?2 g · cm?2 · s?1/2 in the glycerol solution, respectively. Moreover, above the concentrations of the end points of the transition phenomenon, the ΔF values of the sucrose solution are equal to those of 90° at all immersion angles. On the other hand, those of the glucose and the glycerol solutions are the same as those of 30°. This difference may be caused by inherent characteristics of adsorption to the surface of the QCM electrode. 相似文献
63.
Improvement in the oxidation resistance of SUS304 stainless steel was accomplished by electrodeposition of La in a molten salt. The electrolysis of La was conducted using a potentiostatic-polarization method in an equimolar NaCl–KCl melt containing 3.5 mol. LaF 3 at 1023 K. Observation of the specimen surface after polarization at –1.8 V (vs. Ag/Ag+ (0.1)) for 0.18 ks showed that La particles were uniformly dispersed on the surface. The oxidation resistance of the electrodeposited stainless steel was significantly improved as compared with the untreated stainless steel. The scale formed on the untreated stainless steel after oxidation was thick and consisted of Fe2O3 and Fe3O4, whereas the scale formed on the elecrodeposited stainless steel was extremely thin, and mainly consisted of Cr2O3. 相似文献
64.
DRY MACHINING is a keyword for manufacturingand production science in the twenty-first century,which requires significant reduction of environmentalburden and COi emission11.In the modern high-speedwet and semi-dry machining processes,huge amountsof lubricants and cleansing agents are wasted in dailyproduction2).Among various proposals aiming at thedry machining3"5>,in-situ formation of tribo-filrns mustbe an important concept to make dry machining tools.Authors have pointed out the impor… 相似文献
65.
Akihiko Sugai Rie Sakuma Ikuko Fukuda Norio Kurosawa Yuko H. Itoh Kazuo Kon Susumu Ando Toshihiro Itoh 《Lipids》1995,30(4):339-344
The major ether-type lipid structures ofSulfolobus acidocaldarius (ATCC33909) were composed of caldarchaeol and calditoglycerocaldarchaeol. However, the characterization by nuclear magnetic
resonance spectroscopy and mass spectrometry showed that the structure of calditol in calditoglycerocaldarchaeol is not nonitol,
2-(1′,2′,3′-trihydroxypropyl)1,2,3,4,5,6-hexahydroxyhexane, but 2-hydroxymethyl-1-(2,3-dihydroxypropoxy),2,3,4,5-cyclopentanetetraol
with an ether linkage in the molecule. Such an intermolecular ether linkage was resistant, to BCl3 treatment, but nonresistant to 57% HI degradation treatment conducted at 100°C for 60 h, producting 2-hydroxymethyl-1,2,3,4,5-cyclopentanepentaol
from calditol as reaction product. Further, it was confirmed that the structure of calditol is essentially a derivative of
glycerol, and hydrocarbon chains were conjugated to the glycerol-like site in the structure. The calditol with an ether linkage
in the molecule suggested an important role regarding the properties of heat-resistance and acid-resistance observed inSulfolobales.
Presented at the international workshop on “Molecular Biology and Biotechnology of Extremophiles and Archaebacteria,” Wako,
Japan, August 1993. 相似文献
66.
Masaaki Suzuki Yoshihisa Hasegawa Masayuki Aizawa Yoshinori Nakata Takeshi Okutani Kohei Uosaki 《Journal of the American Ceramic Society》1995,78(1):83-89
The structure of silicon carbide–silicon nitride (SiC–Si3 N4 ) composite particles synthesized using a CO2 laser was studied by magic angle spinning nuclear magnetic resonance (MAS-NMR) and electron spin resonance (ESR). The structure around Si atoms changed by introducing N. C atoms around Si were substituted by N atoms, and N-rich configurations around Si atoms increased stepwise as the N content increased. The low N content composite particles consisted of mainly SiC phase containing dissolved N. N atoms were partly present in β-SiC microcrystal and partly in the grain boundary layer in the particle. N atoms were tetrahedrally surrounded by four Si atoms in β-SiC microcrystal and were trivalent state bonded to three Si atoms in the grain boundary layer. The high N content particles consisted of SiC, Si3 N4 , and amorphous phases, whose amount depended on N content. 相似文献
67.
Yusuke Suzuki Chisato Takenaka Rie Tomioka Hiromi Tsubota Yuka Takasaki Tomonari Umemura 《Mine Water and the Environment》2016,35(3):265-272
Bryophytes with high As accumulation affinity were identified in the aquatic environment. We surveyed a stream near copper mine tailings and then conducted laboratory experiments to confirm As accumulation in the bryophytes with high As affinity. We found that a moss, Scopelophila cataractae, accumulates As in addition to Cu in aquatic environments and confirmed it in laboratory experiments. The highest value for As in S. cataractae from the field survey was 1300 mg/kg dry weight at relatively low As concentrations in the stream water (0.005 mg/L). In addition, Brachythecium plumosum and Rhynchostegium riparioides may also be useful bryophytes for accumulation of Cu and As, though the mechanisms of As accumulation might differ between these two bryophytes and S. cataractae. 相似文献
68.
In urban environments, front yards and backyards are valued by residents for the opportunities they provide for enriching residential activities and promoting neighbourly ties. This article extends previous inquiries to identify the preferred uses and attributes of side setback areas in a comparatively dense urban environment. While front yards or backyards may contribute to sociability, no such effects have been reported for the side setback areas, with their function being instrumental rather than social. On the basis of a 2013 survey, the average side setback area in Sapporo (Japan) is <2 m wide and its typical use is for storage. A series of cross-statistical analyses was used to investigate possible correlations and to predict the role of the physical attributes of adjacent facades on the perceptions of the respondents. This was followed by an in-depth interview of those who volunteered. The results indicated that side setback areas that were lesser than 1-m wide were perceived as abandoned and assumed to have no function. However, those wider than 1 m were seen as secondary storage areas. Regardless of this, respondents valued the light and ventilation provided by side setback areas. 相似文献
69.
70.
Yoichi Wada Atsushi Watanabe Kazushige Ishida Masahiko Tachibana Motohiro Aizawa Motomasa Fuse 《Journal of Nuclear Science and Technology》2013,50(5):546-555
A calculation model on intergranular stress corrosion cracking (IGSCC) initiation time of materials used in boiling water reactors (BWRs) has been developed to evaluate effectiveness of water chemistry control for mitigation of the IGSCC. The model was composed of four terms which determine passive film break time: (1) a chemical term based on electrochemical corrosion potential (ECP) and impurity concentration; (2) a mechanical term based on strain rate; (3) a material term based on sensitization; and (4) an irradiation term based on acceleration of corrosion by γ-rays and neutron irradiation. The contribution of the chemical term in the passive film break was calculated based on a deterministic local corrosion model. Then, the local corrosion model was modified by adding mechanical acceleration of the film rupture to treat the IGSCC phenomenon. The model could reproduce the behavioral tendency seen in the slow strain rate tensile test on high carbon contents with sensitization heat treatment (for example, 620°C × 24 h). Under BWR operating conditions, IGSCC initiation time could be extended by a factor of 5 by lowering the electric conductivity from 1.0 to 0.06 μS/cm. If the ECP was reduced below the critical potential by a mitigation method, the IGSCC initiation time was predicted to become sufficiently long for pipings and components. 相似文献