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Takaaki Wajima Tomoe Shimizu Yasuyuki Ikegami 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2008,83(6):921-927
BACKGROUND: This study aimed to investigate the synthesis of zeolites from paper sludge ash (PSA) with added diatomite to remove both NH4+ and PO43? for water purification. The PSA had low Si and significant Ca contents. Four types of diatomite: white (T‐W) and brown (T‐B) from deposits of marine origin in Takanosu, and white (S‐W) and gray (S‐G) from lacustrine deposits in Shonai, were added to NaOH solution to increase the Si content and thereby synthesize zeolites with high cation exchange capacity (CEC). RESULTS: The order of the amounts of Si extracted from the diatomite to the alkali solution was S‐W > T‐W = T‐B > S‐G, which correlates with the amorphous SiO2 content of diatomite. The original ash without addition of diatomite yielded hydroxysodalite with CEC of about 1.0 mmol g?1. For all samples, the addition of diatomite to the solution yielded zeolite‐P with a higher CEC, but the addition of excess Si inhibited the synthesis of zeolite‐P, and the CEC of the product was low. A product with high CEC including zeolite‐P was obtained in a solution with around 500 mmol L?1 of Si concentration, and had the ability to remove both NH4+ and PO43?. CONCLUSION: Diatomite has the potential for used as an additive for the synthesis of high CEC zeolite from PSA. The product with zeolite‐P exhibited relatively high CEC, capacity for NH4+ uptake, and the ability to remove PO43? by precipitation, which is preferable for water purification applications. Copyright © 2008 Society of Chemical Industry 相似文献
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K Tarao H Hoshino A Shimizu S Ohkawa M Harada Y Nakamura Y Ito S Tamai N Okamoto 《Canadian Metallurgical Quarterly》1995,75(6):1255-1262
BACKGROUND: The relationship between echosonographic patterns of patients with cirrhosis who are antihepatitis C virus (HCV)-positive, the DNA synthesis of hepatocytes, and the risk for HCC were studied. METHODS: Thirty-eight patients with anti-C-100 antibody-positive and Child's grade A posthepatitic cirrhosis were studied. DNA synthesis activity was measured by a bromodeoxyuridine (BrdU, a thymidine analogue)-labeling index (LI), using the BrdU-anti-BrdU in vitro method, and the patients were followed prospectively by frequent liver ultrasonography for 3 years. The ultrasound patterns were classified into fine, coarse, and coarse-nodular (CN) patterns, and the reproducibility of the classification in practical use also was confirmed. RESULTS: Of the 21 patients with high DNA synthesizing cirrhosis (BrdU LI > or = 1.5%), 10 (48%) showed coarse-nodular, 5 (24%) coarse, and 6 (29%) fine pattern in ultrasonography. Conversely, of the 17 patients with low DNA synthesizing LC (BrdU LI < 1.5%), only 1 (6%) showed coarse-nodular, 2 (12%) coarse, and 14 (82%) fine pattern. A significant relationship was found between the two groups of BrdU LI and ultrasound imaging patterns (P < 0.05). The incidence of CN pattern was significantly higher (P < 0.01) in the high DNA synthesizing group than in low DNA synthesizing group. Of the 11 patients with CN pattern by ultrasound imaging, 10 (91%) were in the high DNA synthesizing group, and 9 (82%) developed HCC during the follow-up period, compared with 3 of 7 (43%) with coarse, and only one of 20 (5%) with fine pattern developed HCC. The incidence of HCC was significantly higher (P < 0.01) in patients with a CN cirrhosis pattern than in those with a fine pattern. CONCLUSIONS: In patients with cirrhosis who are anti-HCV-positive, the CN pattern by ultrasound imaging indicates increased DNA synthesis of hepatocytes and a high risk for developing HCC. 相似文献
25.
E Kojima M Izumi T Tanabe M Matsuda T Shimizu A Murakami K Murakami 《Canadian Metallurgical Quarterly》1997,(37):171-172
The extent of genetic identity observed in the young individuals which were micropropagated from a single Eucalyptus individual was analyzed by using DNA-fingerprinting. Among 40,000 tissue-cultured-seedings of E.citriodora, 200 plants were randomly chosen so that each total DNA might be extracted from their leaves. Using these DNAs as template, PCR was performed with some primers we found in advance that leads polymorphism for DNA of E. citriodora. In this study, all over the 200 cases, the band pattern formed cDNA fragment on a gel after electrophoresis was the identical one mutually. 相似文献
26.
Shimizu H. Harada J. Bland C. Kawakami K. Chan L. 《Industrial Electronics, IEEE Transactions on》1997,44(1):14-18
In 1994, the Eco-Vehicle Project was begun to develop an electric vehicle (EV) using a ground-up design approach that incorporates unique designs specific to an EV. The Eco-Vehicle will be a high-performance, but ultrasmall, battery-powered vehicle. New designs for the Eco-Vehicle include an in-wheel motor drive system, a hollow load floor which will house the batteries, and a new battery management system. The Eco-Vehicle may also utilize other advanced concepts suitable especially for EVs, including solar panels for battery charging and intelligent crash avoidance and guidance systems 相似文献
27.
The amplification characteristics of a high Tm3+ concentration gain-shifted Tm-doped fluoride fibre amplifier (GS-TDFA) have been determined with a high input signal power. This GS-TDFA achieved the highest reported internal power conversion efficiency of 70% with a double pass configuration 相似文献
28.
K Fukuoka M Hirokawa M Shimizu K Fujiwara I Kohno M Shintaku T Manabe 《Canadian Metallurgical Quarterly》1998,48(9):754-756
A case of oxyphilic cell variant of endometrioid adenocarcinoma is presented. To the best of our knowledge, there have been only three such cases reported in the English literature. The patient was a 35-year-old Japanese female (gravida 0, para 0). She was slightly obese with profuse vaginal bleeding. Histological examination of the resected uterus revealed endometrioid adenocarcinoma with an exclusive oxyphilic cell component. There was no evidence of myometrial invasion nor lymph node metastases. Reported cases of oxyphilic cell variant of endometrioid adenocarcinoma, including the present case, were stages 0-1 and grades 1-2. Although further study is necessary to evaluate this variant, oxyphilic cell variant seems to be an early stage of adenocarcinoma and should be differentiated from eosinophilic metaplasia and other types of adenocarcinoma of the endometrium. 相似文献
29.
F. Monfort A. Berkani G.E. Thompson K. Shimizu 《Surface & coatings technology》2007,201(21):8671-8676
The mechanism of coating growth during sparking anodizing of aluminium is probed by use of an electrolyte containing both silicate and phosphate ions, with subsequent determination of the locations of silicon and phosphorus species through the coating thickness. Importantly, the main alumina-based layer of the coating contains incorporated silicon and phosphorus species of differing distributions. Phosphorus species are primarily found in a region next to the metal, representing roughly about 30% of the layer thickness. Silicon species are located mainly above this region to the layer surface. New coating material is added in discreet amounts associated with breakdown events, which provide short-circuit paths through the layer. The growth processes within the discharge region result in separation of the silicate- and phosphate-derived species, which may relate to their different mobilities, dependent upon factors such as charge, size and bonding with other species. Further, silicon-rich material is deposited at the surface of the alumina-based layer, which is often encountered in spark anodizing in silicate electrolyte. 相似文献
30.
Carlos R. Vera Carlos L. Pieck Kiyoyuki Shimizu Jos M. Parera 《Applied Catalysis A: General》2002,230(1-2):137-151
An assessment of the influence of the crystal structure, surface hydroxylation state and previous oxidation/reduction pretreatments on the activity of sulfate-zirconia catalysts for isomerization of n-butane was performed using crystalline and amorphous zirconia supports. Different sulfation methods were used for the preparation of bulk and supported SO42−-ZrO2 with monoclinic, tetragonal and tetragonal+monoclinic structures. Activity was important only for the samples that contained tetragonal crystals. The catalysts prepared from pure monoclinic zirconia showed negligible activity. SO42−-ZrO2 catalysts prepared by sulfation of crystalline zirconia displayed sites with lower acidity and cracking activity than those sulfated in the amorphous state. Prereduction of the zirconia samples with H2 was found to greatly increase the catalytic activity, and a maximum rate was found at a reduction temperature of 550–600 °C, coinciding with a TPR peak supposedly associated with the removal of lattice oxygen and the creation of lattice defects. A weaker dependence of catalytic activity on the density or type of surface OH groups on zirconia (before sulfation) was found in this work.
A model of active site generation was constructed in order to stress the dependence on the crystal structure and crystal defects. Current and previous results suggest that tetragonal structure in active SO42−-ZrO2 is a consequence of the stabilization of anionic vacancies in zirconia. Anionic vacancies are in turn supposed to be related to the catalytic activity for n-butane isomerization through the stabilization of electrons from ionized intermediates. 相似文献