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排序方式: 共有673条查询结果,搜索用时 125 毫秒
71.
Variation of Fructooligosaccharides and their Metabolizing Enzymes in Onion Bulb (Allium cepa L. cv. Tenshin) During Long-term Storage 总被引:1,自引:0,他引:1
Noureddine Benkeblia Keiji Ueno Shuichi Onodera Norio Shiomi 《Journal of food science》2005,70(3):S208-S214
ABSTRACT: The objective of this study was to assess the status of fructooligosaccharides (FOS) in onion bulbs ( Allium cepa L. cv. Tenshin) and their metabolizing-enzymes—1-fructoexohydrolase (1-FEH), 1-kestose hydrolyzing enzyme (1-KH), fructan:fructan 1F -fructosyltransferase (1-FFT) and fructan:fructan 6G -fructosyltransferase (6G-FFT)—during storage at 15°C. Fructose varies slightly, whereas 1-kestose peaked after 6 wk and then decreased progressively during the last 18 wk of storage. Lower degree of polymerization (DP) 3 to 6) FOS, higher (DP 7 to 12) FOS, total FOS, and total carbohydrates showed similar and close patterns during 24 wk. They varied slightly at the beginning of the storage period; afterward they decreased progressively and regularly during the last 20 wk of storage. 1-FEH and 1-KH activities were low but peaked abruptly after 12 and 16 wk, respectively, after which they decreased to levels higher (1-FEH) or similar (1-KH) to those observed at the beginning of the storage. Surprisingly, 1-FFT activity showed similar pattern to the variation of 1-KH hydrolyzing activity; on the other hand, 6G-FFT, although higher, was stable during 16 wk but decreased after that. The results allowed us to associate FOS to the dormancy and sprouting states, and the peaks of the degrading enzymes were shown to signal the release of dormancy of onion bulb. 相似文献
72.
Reforming of Methane with Carbon Dioxide over a Catalyst Consisting of Ruthenium Metal and Cerium Oxide Supported on Mordenite 总被引:1,自引:0,他引:1
Reforming of CH4 with CO2 proceeds at 400 °C over a catalyst consisting of ruthenium metal and CeO2 highly dispersed on mordenite. The catalyst, Ru-CeO2/MZ, is highly active for the reforming of CH4 under the conditions at which a carbon formation reaction is thermodynamically apt to take place. The reforming selectively forms H2 and CO. An increase in the weight of the catalyst resulting from carbon deposits was scarcely observed. IR spectra for the catalyst indicate that the reforming proceeds via the formation of the intermediate species such as Ru-CO and Ru-CHx on the surface of ruthenium. The data of H2 adsorption support the idea that ruthenium is highly dispersed in Ru-CeO2/MZ. 相似文献
73.
Keiji Nakajima Hajime Hasegawa Sakhob Khumkoa Shozo Mizoguchi 《Metallurgical and Materials Transactions B》2003,34(5):539-547
In order to elucidate the nature of the heterogeneous nucleation, a differential scanning calorimetry (DSC) thermal analysis
of pure Fe and Fe-Ni alloys (Ni content: 1.0 to 29.3 mass pct) containing TiN, Al2O3, and Ti2O3 was conducted. Then, special attention was paid to the difference in the phase of the primary crystal nucleated by the triggering
effect of a catalyst (nucleating agent). The solidification and transformation mode appearing during cooling in these alloys
is classified into three cases: F mode, FA mode, and A mode. The change of modes and the critical undercooling (ΔT) depend on the kind of catalyst used as well as the chemical composition (Ni content). In addition, in spite of the kind
of primary crystal, the value of ΔT is always small in the order of TiN, Al2O3, and Ti2O3. As a matter of fact, only TiN has a practical effect as a catalyst on the triggered nucleation of the primary crystal of
the δ phase. None of them has a practical effect on the nucleation of the primary crystal of the γ phase.
This article is based on a presentation given in the Mills Symposium entitled “Metals, Slags, Glasses: High Temperature Properties
& Phenomena,” which took place at The Institute of Materials in London, England, on August 22–23, 2002. 相似文献
74.
Alumina has been incorporated in the cavities of mordenite by the hydrolysis of Al3+ ions in the cavities with moist ammonia gas, following calcination at 450°C. The incorporation of the superfine particles of alumina into the cavities of the mordenite is assessed on the basis of the data of MAS 27Al NMR measurements, X-ray powder diffraction and the amount of saturated adsorption of nitrogen for FAL/MZ. The acid properties, assessed using NH3 TPD and FTIR studies, show the presence of Brønsted and Lewis acid sites on the catalyst, and an increase in acidic sites on incorporating alumina. The dehydrogenation selectivities of FAL/MZ, Al3+/MZ, H+/MZ, and Na+/MZ have been investigated. Brønsted acid sites largely enhance the ring-cleavage, whereas this incorporation of superfine particles of alumina significantly suppresses the ring-cleavage. Therefore, the incorporation of the superfine particles increases remarkably in the cyclohexene selectivity. 相似文献
75.
76.
77.
A Maruoka H Fujishima T Misawa Y Chijiiwa H Nawata 《Canadian Metallurgical Quarterly》1993,28(12):1055-1061
To clarify the ability of endoscopic ultrasonography (EUS) to diagnose gastric ulcer, we induced gastric ulcer (19 open ulcers and 11 ulcer scars) by injecting acetic acid into the stomach via an endoscope in 15 dogs. The stomachs were resected and scanned by EUS in a water bath, and the findings were compared with the histologic observations. The ulcer depth was correctly diagnosed in 29 of 30 instances (96.7%). In active, open ulcers the width and depth of the ulcer crater and the thickness of the gastric wall around the crater measured in the photographs obtained by EUS corresponded with those observed in histologic photographs. In the ulcers disrupting the muscularis propria layer the distance between the disrupted muscularis propria layer in EUS also corresponded to the histologic observations. In all ulcer lesions the low-echoic area below the ulcer in EUS corresponded to the histologic area of granulation or fibrosis. However, it was difficult to distinguish granulation from fibrosis by EUS. EUS is thus considered useful for evaluating gastric ulcers quantitatively in the clinical setting. 相似文献
78.
SJ Kim T Ishibashi H Saito S Maruoka S Higano A Sato S Takahashi S Yamada H Hama K Koyama T Mitomo 《Canadian Metallurgical Quarterly》1998,58(3):94-96
This communication describes one pediatric neurosurgeon's personal view of the neurosurgical perspectives in pediatric neurooncology. Various roles of surgery, including histological verification, maximum cytoreduction, neurodecompression and restoration of the cerebrospinal fluid pathway, are emphasized. A pediatric neurosurgeon, who is the first person to make decisions on diagnosis and treatment relating to children with brain tumors, should be up to date with advances in diagnostic and therapeutic methods. Particularly, he or she should be familiar with both the efficacy and the side effects of radiation therapy and chemotherapy to allow selection of the optimum treatment for such children. 相似文献
79.
Shoji Maruoka 《Water research》1978,12(6):371-375
Cultured mammalian cells were used to examine the toxicity of the organic pollutants present in Lake Biwa. The pollutants were adsorbed on activated carbon and extracted respectively with methylene chloride, chloroform, acetone and ethanol. It was found that the toxicity of the extracted organic pollutants varies markedly with the solvent used. The results herein suggest that substances extractable with methylene chloride are most important for estimating the organic pollution in aquatic environments. The conspicuous seasonal variation in the toxicity, as well as the concentration, of methylene chloride and chloroform extractable substances was marked. 相似文献
80.
A λ-type specific heat anomaly of U4O9?y, which occurs slightly above room temperature, was measured for the samples with different O/U ratios. The transition temperatures obtained from the peak of λ-type specific heat anomaly are in fairly good agreement with the data by X-ray diffraction and electrical conductivity measurements. The entropy increment for the transition was obtained to be 0.46 e.u. for UO2.250, 0.56 e.u. for UO2.240 and 0.70 e.u. for UO2.228, depending on O/U ratio. On the basis of the entropy change with O/U ratio, the mechanism of the phase transition is discussed. The entropy change due to the phase transition is mainly divided into two terms: one is due to the order-disorder rearrangement of U(IV) and U(V) ions,the other is associated with the displacement of oxygens ions. The former term is estimated to be rather smaller than the entropy change calculated by the Bragg-Williams approximation, and the latter is calculated using the X-ray diffraction data with the assumption of the Willis model. 相似文献