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201.
H Yano H Iishi M Tatsuta N Sakai H Narahara M Omori 《Canadian Metallurgical Quarterly》1998,45(24):2138-2141
BACKGROUND/AIMS: Conscious sedation increases the tolerance of patients to endoscopic examination, but arterial oxygen desaturation during endoscopy has often been reported. Elderly patients are considered to be at special risk. However, sedation-induced changes in cardiovascular function in the elderly have not been well investigated. Therefore, this study examined the effects of sedation on pulse rate, systolic blood pressure, and arterial oxygen saturation in elderly patients. METHODOLOGY: Twenty patients aged less than 60 years and 20 patients aged 60 years or more, scheduled to undergo colonoscopic removal of colorectal polyps, received 0.05 or 0.025 mg/kg body weight, respectively, of midazolam intravenously. Before, during, and after endoscopy, pulse rate, systolic blood pressure, and arterial oxygen saturation were recorded every 5 min with a pulse oximeter. RESULTS: Administration of midazolam had no significant effect on pulse and arterial systolic blood pressure in either group. In contrast, midazolam significantly reduced the levels of arterial oxygen saturation during and after endoscopy in both age groups. However, although patients aged 60 years or more received midazolam at half dosage, arterial oxygen saturation during endoscopy was significantly lower and the incidence of 5% or more oxygen desaturation was significantly higher than in the patients aged less than 60 years. CONCLUSIONS: Midazolam increases the tolerance of elderly patients to endoscopy, but it significantly lowers the level of arterial oxygen saturation and increases the incidence of desaturation. Continuous monitoring is especially valuable during endoscopy in the elderly. 相似文献
202.
Haruki Madarame Shuichi Iwata Shunsuke Kondo Atsuyuki Suzuki Hidetoshi Shimotono Kenzo Miya Masaharu Nakazawa Yoshiaki Oka Satoru Tanaka Masatsugu Akiyama Hiroyuki Hashikura Hitoshi Kobayashi Seiichi Tagawa 《Nuclear Engineering and Design》1983,74(3):377-392
UTLIF(1) is a conceptual design study on a light ion beam driven fusion reactor based on a concept of pin-bundle blanket. The study includes nuclear and structural analyses of the blanket, consideration on materials, tritium handling system and power conversion system designs, pellet and beam driver designs, and economic analysis of the plant. The pin-bundle blanket has been shown to be attractive for light ion beam fusion reactors. Some subjects to be developed have been pointed out from reactor engineering aspects. 相似文献
203.
204.
This article demonstrates the characteristics, physical construction, and application for a newly commercialized high-frequency static induction transistor (SIT). The main features of this device are a lowering in the gate-to-source and gate-to-drain capacitances and an increase in the breakdown voltage and power rating. These enhancements were brought about as a result of the introduction of new and refined manufacturing technologies. The new high-frequency SIT device is being applied in applications such as medium wavelength radio transmitters and induction heaters 相似文献
205.
Kouji Shiina Tsutomu Kawamura Masaya Ohtsuka Tadashi Mizuno Masakazu Hisatsune Kenji Ogura Kouichi Tanimoto Toshihiko Fukuda Yasuhiko Minami Shoichi Moriya Haruki Madarame 《亚洲传热研究》2007,36(1):38-55
In a branch pipe with one closed end, the cavity flow penetrates into the branch pipe from the main loop and a thermal boundary layer occurs because the cavity flow is a hot fluid, but heat removal causes a colder fluid in the branch pipe. This thermal stratification may affect the structural integrity. Therefore, a pipe design standard to suppress thermal fatigue should be established. The pipe design standard consists of the maximum penetration depth Lsv and the minimum penetration depth Lsh. In order to establish an evaluation method for Lsh, a visualization test and a temperature fluctuation test were carried out. A theoretical formula for thermal stratification was introduced from the heat balance model. Then the model was used to obtain an empirical equation from the map of fluid temperature fluctuation. This method can predict the vortex penetration depth by cavity flow in horizontal branch pipes. © 2006 Wiley Periodicals, Inc. Heat Trans Asian Res, 36(1):38–55, 2007; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/htj.20135 相似文献
206.
Effect of High‐Pressure Oxygen Annealing on Electrical and Magnetoelectric Properties of BaSrCo2Fe11AlO22 Ceramics
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Sakyo Hirose Kohei Haruki Akira Ando Tsuyoshi Kimura 《Journal of the American Ceramic Society》2015,98(7):2104-2111
The effect of high‐pressure oxygen (HPO) annealing on the electrical, magnetic, and magnetoelectric (ME) properties of room‐temperature multiferroic BaSrCo2Fe11AlO22 ceramics was investigated. The electrical resistivity of the ceramics was found to strongly depend on the partial oxygen pressure during annealing at 1040°C. Samples annealed under ~10 atm of oxygen exhibited a resistivity of up to 1.6 × 109 Ω·cm at room temperature, more than two orders of magnitude higher than that of samples without oxygen annealing. Thermally stimulated current and complex impedance measurements suggested that the enhancement of the resistivity by the HPO annealing originated from a decrease in the amount of defects related to oxygen vacancies and an increase in the resistance of grains and interfaces. HPO annealing also affects the magnetic‐field response of spiral magnetic ordering, which is ascribed to the ME properties. Furthermore, samples subjected to HPO annealing exhibited a lower contribution of the space charges trapped at the grain boundaries and/or defects to the magnitude of the measured magnetoelectrically induced electric polarization P. The present results indicate that HPO annealing is an effective method to evaluate authentic ME effects in multiferroic BaSrCo2Fe11AlO22 ceramics. 相似文献
207.
Gene cloning and characterization of aldehyde dehydrogenase from a petroleum-degrading bacterium, strain HD-1 总被引:1,自引:0,他引:1
Okibe N Amada K Hirano S Haruki M Imanaka T Morikawa M Kanaya S 《Journal of Bioscience and Bioengineering》1999,88(1):7-11
The hd-ald gene encoding aldehyde dehydrogenase (hd-ALDH) from an mixotrophic petroleum-degrading bacterium, strain HD-1 was cloned and sequenced. hd-ALDH (506 amino acids) is a member of the NAD+-dependent aldehyde dehydrogenase group. The hd-ald gene was expressed in Escherichia coli, and the recombinant enzyme was purified and characterized biochemically and enzymatically. The molecular weight of the enzyme was estimated to be 55,000 by SDS-PAGE, and 224,000 by gel filtration chromatography, suggesting that it acts as a tetramer. The CD spectrum suggests that the helical content of the enzyme is 10%. hd-ALDH was active on various aliphatic aldehyde substrates. The K(m) values of the enzyme were 6.4 microM for acetaldehyde, 4.2 microM for hexanal, 2.8 microM for octanal, and 0.84 microM for decanal, whereas the kcat values for these substrates were nearly equal (51-64 min(-1)). These results indicate that hd-ALDH acts preferentially on long-chain aliphatic aldehydes. 相似文献
208.
RNase H is an enzyme that specifically cleaves RNA hybridized to DNA. The enzyme is ubiquitously present in various organisms. Single bacterial and eucaryotic cells often contain two RNases H, whereas single archaeal cells contain only one. To determine whether there is a physiological significance in the ubiquity and multiplicity of the enzyme, and whether all enzymes are evolutionarily diverged from a common ancestor, we carried out phylogenetic analyses of the RNase H sequences. In this report, we demonstrated that RNases H are classified into two major families, Type 1 and Type 2 RNases H, of which only the Type 2 enzymes are present in all living organisms, including bacteria, archaea, and eucaryotes, suggesting that they represent an ancestral form of RNases H. Based on this information, we discuss the evolutionary relationships and possible cellular functions of RNases H. 相似文献
209.
Haruki Uchiyama Kohei Maruyama Edward Chen Tomonori Nishimura Kosuke Nagashio 《Small (Weinheim an der Bergstrasse, Germany)》2023,19(15):2207394
Achieving the direct growth of an ultrathin gate insulator with high uniformity and high quality on monolayer transition metal dichalcogenides (TMDCs) remains a challenge due to the chemically inert surface of TMDCs. Although the main solution for this challenge is utilizing buffer layers before oxide is deposited on the atomic layer, this method drastically degrades the total capacitance of the gate stack. In this work, we constructed a novel direct high-κ Er2O3 deposition system based on thermal evaporation in a differential-pressure-type chamber. A uniform Er2O3 layer with an equivalent oxide thickness of 1.1 nm was achieved as the gate insulator for top-gated MoS2 field-effect transistors (FETs). The top gate Er2O3 insulator without the buffer layer on MoS2 exhibited a high dielectric constant that reached 18.0, which is comparable to that of bulk Er2O3 and is the highest among thin insulators (< 10 nm) on TMDCs to date. Furthermore, the Er2O3/MoS2 interface (Dit ≈ 6 × 1011 cm−2 eV−1) is confirmed to be clean and is comparable with that of the h-BN/MoS2 heterostructure. These results prove that high-quality dielectric properties with retained interface quality can be achieved by this novel deposition technique, facilitating the future development of 2D electronics. 相似文献
210.
Gaku Okuma Masaya Endo Haruki Minagawa Ryo Inoue Hideki Kakisawa Takuma Kohata Toshio Osada Takafumi Yamamoto Masaki Azuma Akihisa Takeuchi Masayuki Uesugi Olivier Guillon Fumihiro Wakai 《Advanced Engineering Materials》2023,25(18):2201534
The mechanical reliability of products must be assured for scaling up and production of complex-shaped components by spark plasma sintering (SPS) of spray-dried granules. The evolution of morphologies of pores and defects, which control the mechanical strength, is investigated by using synchrotron X-ray multiscale tomography during SPS of alumina granules at 1300 °C. While large defects arising from the hierarchical granule packing structure cannot be removed by pressureless sintering, crack-like defects and branched rodlike defects are almost eliminated by SPS at stresses higher than 30 and 50 MPa, respectively. But, small ellipsoidal porous regions, which may arise from aggregates or dimples of granules, cannot be removed even at a pressure of 50 MPa. A very large defect is also found by using micro-CT. It is supposed that this defect is formed from a large void in loosely packed granules. The shrinkage of large voids and the elimination of crack-like defects are explained by the theoretical prediction based on the continuum theory of sintering. 相似文献