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241.
242.
Changes in triacylglycerols (TAG) and phospholipids (PL) compositions of cooked Japanese sardine meats as such or with prior addition of ethylene diaminetetracetic acid (EDTA) or a combination of nitrite and ascorbate were evaluated during chilled storage using gas chromatography and selected ion monitoring gas chromatography/mass spectrometry. The TAG molecular species compositions remained unchanged, while certain species of PL molecular species changed during storage at 2 °C for 14 days. The PL containing polyunsaturated fatty acids were highly susceptible to autoxidation. The PL fractions play an important role in oxidative rancidity and development of off-flavor in cooked sardine meat, while TAG fraction plays a minor role in the oxidative deterioration of the meat. Changes in peroxide and thiobarbituric acid values were also monitored. Added EDTA was not effective in controlling the decomposition of lipid hydroperoxide throughout the storage period. However, a combination of NaNO2 and ascorbate not only suppressed the formation but also the decomposition of the primary oxidation products. 相似文献
243.
Nobuko Onozawa-Komatsuzaki Masatoshi Yanagida Takashi Funaki Kazuyuki Kasuga Kazuhiro Sayama Hideki Sugihara 《Inorganic chemistry communications》2009,12(12):1212-1215
A new ruthenium(II)–polypyridine complex (1) having a 2,6-bis(4-carboxyquinolin-2-yl)pyridine ligand was synthesized as a sensitizer for dye-sensitized solar cells (DSCs). This complex exhibited remarkable light-harvesting properties in the near-IR region. DSCs sensitized with 1 showed a 35% incident photon-to-current conversion efficiency (IPCE) at 900 nm. 相似文献
244.
The flashover voltage with a backside electrode was found to be lower than that without the backside electrode. Under microsecond pulse voltage application, we describe the characteristics of a creeping discharge developed in the narrow gap with the backside electrode. Using a CCD camera and ultrahigh‐speed camera, we observed the corona extension processes. The lowest flashover voltage was found to be obtained at positive polarity with a SF6 content D = 3%. In the corona extension obtained using an ultrahigh‐speed camera, peculiar differences were observed in the corona extension process. The corona extension increased, and rapid flashover was observed at D = 3%. Using a CCD camera, small coronas were detected from the backside electrode. © 2006 Wiley Periodicals, Inc. Electr Eng Jpn, 158(2): 31–38, 2007; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20431 相似文献
245.
S Takashima T Saeki I Adachi T Watanabe Y Sasaki H Murai T Tabei M Ogita M Sano K Kanda M Shimoyama 《Canadian Metallurgical Quarterly》1997,27(5):325-330
In a previous study, we found that oral chromium nicotinate overcame sucrose-induced hypertension in spontaneously hypertensive rats (SHR). Accordingly, we examined more chromium compounds to determine if others were more or less effective in regulating blood pressure (BP) of SHR. Since chromium is postulated to be an antioxidant, we also assessed the ability of different chromium compounds to alter free radical formation measured by determining thiobarbituric acid reactive substances (TBARS). The control group of SHR ingested a diet low in chromium, and 5 other groups ate the same diet with various chromium compounds added at 5 ppm-chloride, acetate, nicotinic acid-glycine-cysteine-glutamic acid (NA-AA), picolinate, and nicotinate. Following this, the rats were challenged with drinking water containing 5% and 10% w/v sucrose. Except for NA-AA, all chromium compounds inhibited the sucrose-induced elevation of systolic BP; and acetate, picolinate, and nicotinate chromium compounds lowered HbAIC below control. Only chromium acetate and nicotinate significantly lowered both hepatic and renal TBARS. Chromium picolinate lowered hepatic TBARS, and chromium chloride and NA-AA lowered neither. We conclude that chromium, rather than a specific ligand, plays a major role in ameliorating sucrose-induced BP elevations and can act as an antioxidant. 相似文献
246.
247.
Based on the present state of the art of the separation technology, recycling of fission-product rare elements (FRE) in the FBR spent fuel is discussed. The rad.-waste fractionation is in accordance with the present society's trend toward zero-emission, and the mean of salt-free method utilizing electrochemistry agrees with the principles of the newly established green chemistry. A catalytic electrolytic extraction method is proposed to separate the target, radioactive but potentially strategic elements, Pd, Ru, Rh, Re (Tc), Te and Se dissolved in the HLLW. It avoids secondary waste arising. This method is particularly feasible for the separation of Pd where cyclic reaction of metal cations such as Pd(II) or Fe(II), acting as promoters or mediators and already contained in HLLW, accelerates the electrochemical deposition of Ru, Rh and Re. Elemental separation not only offers alternative material resources to meet expanding demands for catalysts in Fuel Cell/Soft Energy system but is also the first step for transmutation or other selective strategies for waste management of long-lived fission products (LLFP). 相似文献
248.
Yuji Sano 《Drying Technology》1992,10(3):591-622
Drying process of polymer solution,which i s carryed out industrially by three shapes of the drying material,is investigated comprehensively. The three shapes are slab as various polymer films by film casting dryer, cylinder as various synthetic. fibers by solution spinning and sphere (drop) as particle or povder of various food materials and polymers by spray drying. These are analysed basically in common manner by silnul tanews solution of diffusion equations and heat balance equations with activity and concentration dependent diffusion coefficient of polymer-solvent system. The conceptions concerning the 相似文献
249.
The present work illustrates the use of water-soluble cupric(II) salts as ingredients of binder for injection molding of W-10 wt.% Cu. The parts produced are dense, homogeneous and have good surface finish, compared to those produced using conventional binder systems. This new binder system, named Cu-containing binder (CCB), also provides process-simplification benefits. CuCl2 and Cu(NO3) 2 with the purity of 98% were selected for this study. A rapid two-stage process involving drying and thermal decomposition was successful in removing nonmetatlic constituents from 2 to 3 hours. Final density that is above 97% of theoretical value was obtained. 相似文献
250.
The preceding paper[5] demonstrated that nitrogen dissolves in silicate melts either as a free ion or complex anion, being incorporated into silicate
networks. In the present study, the influence of CaF2 addition to CaO-SiO2 melts on the nitrogen solubility was investigated along the liquidus at 1573 K and within the liquidus at 1723 K at constant
CaF2 levels. In the latter case, as the SiO2 content increases from CaO saturation, the total nitrogen content decreases to reach the minimum and then starts to increase
up to the SiO2 saturation. This is in accord with the abovementioned mechanism of nitrogen dissolution, which is supported by the changing
behavior of free and incorporated nitrogen contents with the slag composition. The role of CaF2 is complicated through the formation of fluorosilicates. The CaF2 seems not to function simply as a diluent but to enhance the dissolution of nitrogen by releasing oxygen from silicate networks,
promoting the formation of free nitride ions.
Formerly Graduate Student, Department of Metallurgy, The University of Tokyo. 相似文献