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991.
A magnetic bubble domain is generated on liquid-phase epitaxial (LPE) garnet film by focusing laser light. It is possible to write with only a few milliwatts light power on a thin film with a low anisotropy field. Because the Bi-containing LPE films used have a high Faraday rotation angle, a written bit or bubble can be read out with a high contrast ratio. Because of its low coercivity, the bubble moves along the temperature gradient to the region heated by the light beam and is then stabilized at a corner of a square formed on the film by etching or ion-implantation. Erasure is possible selectively or all together by increasing the bias field. These optical operations of a magnetic bubble are discussed in connection with the material parameters. 相似文献
992.
G Yamada E Tanaka T Miura K Kiyosawa M Yano T Matsushima H Tsubouchi K Ishikawa M Kohara K Hino 《Canadian Metallurgical Quarterly》1995,10(5):538-545
Sixteen medical institutions in Japan collaborated in this study of the epidemiology of hepatitis C virus (HCV) genotypes. A total of 4176 patients with type C chronic liver disease, from the four main islands of Japan, were evaluated. Of those evaluated, 2794 had chronic hepatitis, 727 had liver cirrhosis and 655 had hepatocellular carcinoma. The HCV genotype of the patients was determined by an enzyme-linked immunosorbent assay based on serological genotype 1- and 2-specific recombinant peptides (SG-1 and SG-2, respectively) of the NS4 region. The prevalence of SG-1 and SG-2 HCV was similar in the four main islands of Japan. SG-1 HCV predominated in each disease category (69-76%). The percentage of patients with SG-1 HCV increased by 7%, while that of patients with SG-2 HCV decreased by 7%, as liver disease progressed in severity from chronic hepatitis to carcinoma (P < 0.001). Patients with either SG-1 or SG-2 had a similar mean age and history of blood transfusion. In conclusion, SG-1 HCV was found to predominate in Japan, and the HCV genotype was found to be related to the stage of hepatitis C disease. 相似文献
993.
Miwazawa Satoru Nakanura Fukuzo Yamada Naohei 《Industrial Electronics, IEEE Transactions on》1986,(3):304-309
This paper introduces a new method for developing the control scheme of phase-controlled cycloconverters. In this method, all the input cosine waves are transformed into a set of parallel lines by means of coordinate transformation. As a result, arguments on the time process of both firing delays and control flows are made much easier than by the conventional method in which all the arguments are made in the time domain. As an application, a CVVF-type noncirculating current cycloconverter is controlled using this method. The results show that the proposed method is useful in pursuing appropriate schemes for Micro-computer-based control. 相似文献
994.
BO Lim K Yamada M Nonaka Y Kuramoto P Hung M Sugano 《Canadian Metallurgical Quarterly》1997,127(5):663-667
A Schistosoma mansoni adult worm anionic fraction (PIII) has previously been shown to protect mice against challenge infection and to reduce pulmonary and hepatic granulomatous hypersensitivity. Serum from PIII-immunized rabbit was used to screen a lambda gt11 cDNA library from S. mansoni adult worm in order to identify antigens capable of modulating granulomatous hypersensitivity. We obtained four clones with 400 (Sm-III.11), 900 (Sm-III.16), 1100 (Sm-III.10) and 1300 (Sm-III.12) bp of length. All clone-specific antibodies were able to recognize most of the PIII components. The sequence analysis showed that these clones presented high homology with S. mansoni paramyosin (Sm-97). These findings ascribe a new function to this antigen with an important role in modulation of granulomatous hypersensitivity to S. mansoni eggs. 相似文献
995.
T Satoh K Tsushima S Saitoh Y Tamura Y Hizawa J Itoh A Munakata Y Yamada 《Canadian Metallurgical Quarterly》1997,24(7):879-882
We reported two cases of advanced gastric cancer effectively treated with chemotherapy of 5-fluorouracil (5-FU), cisplatin (CDDP) and cytarabine (Ara-C), 5-FU (300-350 mg/body) was given by continuous intravenous infusion. Ara-C (20-40 mg/body) by continuous infusion and CDDP (15-20 mg/body) were added intravenously for 3-6 days. For case 1, epirubicin (30 mg/body) was also given on the first day of each therapy course. Case 1 was a 62-year-old female who had gastric cancer with liver metastasis, ovarian metastasis and peritonitis carcinomatosa. After 3 courses of the chemotherapy, reduction of ovarian metastasis greater than 75% was observed. The value of CA125 decreased from 6,800 U/ml to 527 U/ml and ascites disappeared. Case 2 was a 54-year-old male who had type 3 advanced gastric cancer with multiple liver metastases. He received 6 courses of the therapy. Both primary and metastatic tumors showed over 50% reduction in tumor size. These suggested that this combination therapy was effective for inoperable advanced gastric cancers. 相似文献
996.
M Kimura S Tanaka Y Yamada Y Kiuchi T Yamakawa H Sekihara 《Canadian Metallurgical Quarterly》1998,139(7):3249-3253
Dehydroepiandrosterone (DHEA) and its sulfate ester are the most abundant circulating adrenal steroids in humans. Administration of DHEA has been reported to have beneficial effects on obesity, hyperlipidemia, diabetes, and atherosclerosis in obese rodents, although its effects on insulin resistance have not been fully elucidated. In this study, the effects of DHEA treatment on insulin sensitivity were investigated in genetically obese Zucker rats, an animal model of insulin resistance, using the euglycemic clamp technique. After 0.4% DHEA was administered for 10 days to female obese Zucker rats aged 16 weeks, body weight and plasma insulin decreased and glucose disposal rate (GDR), which was normally reduced in obese rats, rose significantly compared with age- and sex-matched control obese rats. On the other hand, although the pair-fed obese rats also showed levels of weight reduction similar to those of DHEA-treated rats, the increase in GDR of DHEA-treated rats was significantly greater than in pair-fed rats, suggesting a direct ameliorating effect of DHEA on insulin sensitivity of obese rats. Serum concentration of tumor necrosis factor (TNF)-alpha, one of cytokines causing insulin resistance, was also reduced significantly in DHEA-treated, but not in pair-fed obese rats. In conclusion, our results suggest that DHEA treatment reduces body weight and serum TNF-alpha independently, and that both may ameliorate insulin resistance in obese Zucker fatty rats. 相似文献
997.
Shigematsu S. Mutoh S. Matsuya Y. Tanabe Y. Yamada J. 《Solid-State Circuits, IEEE Journal of》1997,32(6):861-869
This paper proposes a new multithreshold-voltage CMOS circuit (MTCMOS) concept aimed at achieving high-speed, ultralow-power large-scale integrators (LSI's) for battery-driven portable equipment. The “balloon” circuit scheme based on this concept preserves data during the power-down period in which the power supply to the circuit is cut off in order to reduce the standby power. Low-power, high-speed performance is achieved by the small preserving circuit which can be separated from the critical path of the logic circuit. This preserving circuit is not only three times faster than a conventional MTCMOS one, but it consumes half the power and takes up half the area. Using this scheme for an LSI chip, 20-MHz operation at 1.0 V and only a few nA standby current was achieved with 0.5-μm CMOS technology. Moreover, this scheme is effective for high speed and low-power operation in quarter-micrometer and finer devices 相似文献
998.
Preparation of porous carbons from phase-inversion membranes was investigated as a control method of pore structure in carbon materials. The structure in carbon films was estimated by means of electron microscopy, mercury porosimetry, and gas-adsorption methods. When phase-inversion membranes of Kapton-type polyimide were carbonized, they maintained the film form and gave macroporous carbon films having high porosity. However, micro- and mesopore structures in the carbon films were not influenced by phase inversion in the polymer stage, and, thus, the macroporous carbons had a molecular sieve property similar to that of carbons prepared from nonporous polyimide films. A macroporous structure in cellulose membranes was similarly maintained through the carbonization step, but some of these were fractured or deformed owing to the large shrinkage. Polymer membranes have a capability as porous carbon precursors if they satisfy two requirements: solid-state carbonization and relatively high carbon yield. A composite membrane of a macroporous carbon with a dense carbon having an impervious ability was readily produced by shaping at the precursor stage. © 1995 John Wiley & Sons, Inc. 相似文献
999.
A new protection system for capacitor banks in the case of a short-circuiting accident is described. A pulsed power system composed of many capacitor units and closing switches is well known for producing a controlled pulse current of high power as for the power source of a plasma experimental device, etc. According to the increase of capacity of a bank system, it becomes important to protect the whole bank system from a short-circuiting accident in a capacitor unit. Although some protective ideas have been proposed, these conventional ideas have not been sufficient to absorb the energy flowing into the failure unit from other normal units. Constructing the new 1-MJ capacitor bank for a plasma experimental device, a newly conceived protective device is designed. The new protection system can absorb the bank energy and suppress the short-circuiting current flowing into the failure capacitor units, and overcomes the defect in former protection systems. To confirm the utility of a new protection system, a test of a protection resistor imitating the actual bank circuit was made. The test result showed that absorbable energy for the unit ceramic resistor amounted to 1500 Joule/cc. The new system is adopted to the bank system of the TPE-1RM15 plasma experimental device. 相似文献
1000.
J Mitsuyama H Yamada J Maehana Y Fukuda S Kurose S Minami Y Todo Y Watanabe H Narita 《Canadian Metallurgical Quarterly》1997,39(6):697-705
Exposure of Staphylococcus aureus to 1 x MIC of the quinolone antibiotic pazufloxacin for 24 h, followed by plating on drug-free media, led to the emergence of small colony variants (SCVs) in addition to large colony variants (LCVs). However, following incubation with 0.25 or 4 x MIC of pazufloxacin, only LCVs were obtained. The SCVs were half as susceptible to pazufloxacin or ciprofloxacin as wild-type S. aureus, while the susceptibilities of LCVs were essentially unchanged. The reduced susceptibilities of SCVs did not result from mutations in the quinolone-resistance-determining regions of DNA gyrase and topoisomerase IV, since the sequences of these genes were identical to those of the wild-type. However, the SCVs accumulated pazufloxacin and ciprofloxacin to a lesser degree than did wild-type. Furthermore, their susceptibility to quinolones was almost unaffected by reserpine or verapamil, suggesting that the reduced uptake resulted from decreased permeability, rather than from an active efflux pump. The ability of various quinolones to induce emergence of SCVs in S. aureus, correlated with the presence of carbon-bonded substituents at the C-7 position of a quinoline or naphthyridine nucleus, or with the presence of a benzoxazine nucleus. In conclusion, pazufloxacin-induced SCVs represent a mutant that one might expect to be rapidly eliminated in vivo and, hence, not to survive as a quinolone-resistant pathogen. This finding suggests a novel approach for development of future quinolones. 相似文献