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41.
42.
The terminal SH of liquid polysulfide polymer was capped with a silyl group. This polymer was hydrolyzed immediately by moisture at ambient temperature and returned to the original polymer. The compounds of this new polymer and the various curing agents of the conventional polysulfide polymer became moisture curable and of use as one‐component sealants and adhesives. The curing speed of these compounds is very fast compared with that of not only conventional one‐component polysulfide sealants, by more than three times, but also of other one‐component sealants at 20°C under 30% humidity. Their storage stability is good. Their cured products showed physical properties comparable to those of the two‐component polysulfide compounds. In particular, the compound of this polymer and isocyanate prepolymer showed good elasticity and good weatherability. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 93: 2642–2649, 2004  相似文献   
43.
The polymerization of vinyl monomer initiated by an aqueous solution of poly(N,N,N-trimethyl-N-2-methacryloxyethyl)ammonium chloride (poly(Q-DMAEM-CI) has been carried out at 85°C. The effects of the amounts of vinyl monomer, poly(Q-DMAEM-CI) and water on the conversion of vinyl monomer have been studied. The overall activation energy in the polymerization of MMA is estimated as 41.9 kJ mol?1. The polymerization proceeds through a radical mechanism. The location in which the polymerization occurs is discussed. The selectivity for vinyl monomer is explained by ‘the concept of hard and soft hydrophobic areas and monomers’.  相似文献   
44.
Target enclosure by autonomous robots is useful for many practical applications, for example, surveillance of disaster sites. Scalability is important for autonomous robots because a larger group is more robust against breakdown, accidents, and failure. However, it is more difficult to operate a larger group of robots because their individual capacity for recognizing team-mates should be higher. In this paper, to achieve a highly scalable target enclosure model, we demonstrate a new condition for Takayama??s enclosure model. The original model requires a static relationship between agents. However, robots can form an enclosure even under a dynamic topology on the basis of a nearest neighbor graph; hence, they do not require recognition capability. We confirm this by an analytical discussion of switched systems and a series of computer simulations.  相似文献   
45.
A highly practical diamide-type extractant, which is an alkyl diamide amine with 2-ethylhexyl alkyl chains (ADAAM(EH)), was investigated for the mutual separation of Am(III) and Cm(III). ADAAM(EH) is a multidentate ligand with one soft N-donor atom and two hard O-donor atoms as part of its central frame. This tridentate arrangement of donor atoms provides selective binding to Am(III) compared to that with Cm(III) in highly acidic media (1.5 M HNO3), resulting in separation factors of up to 5.5. A continuous liquid–liquid extraction and stripping test was conducted using a multistage countercurrent mixer-settler extractor with ADAAM(EH) in n-dodecane. In this test, the separation of Am(III) and Cm(III) was achieved with very high yield.  相似文献   
46.
Rice beer samples of nine different varieties from four states of northeast India were studied for the content of organic acids, carbohydrates and amino acids by high‐performance liquid chromatography. The aromatic compounds were detected by gas chromatography–mass spectrometry method. The analysis evinced a wide variation in content of the major organic acids. Lactic acid was found in high concentration in all of the samples, while the other organic acids were present in variable amounts. Among the carbohydrates, glucose was predominant and some other monosaccharides were also detected. Most of the essential amino acids were found to be present and among them aspartic acid was the most abundant. All of the samples contained volatile or semi‐volatile aromatic compounds, with phenylethyl alcohol being the most abundant compound. The overall study revealed that this form of drink has important nutritional values for dietary requirements. Copyright © 2014 The Institute of Brewing & Distilling  相似文献   
47.
The rational operational condition for maximizing the pretreatment effect on plant biomass while minimizing heat required was investigated. Eucalyptus globulus chips were used to evaluate the operational method for the most efficient conversion of plant biomass into useful materials by steam explosion. The energy consumption required to carry out the steam explosion was calculated by considering the mass balances of the water, the wood component, and the heat balance in the steam explosion apparatus. The energy consumption increased significantly with the increase of steam pressure and steaming time, and decreased rapidly with increase of the thickness of the heat‐insulating material in the steam explosion apparatus. The amount of methanol‐soluble lignin, a low molecular weight lignin, was measured experimentally under various operational conditions such as steam pressure and steaming time. The steam explosion at the steam pressure of 3.9 MPa and steaming time of 1.1 min was the most effective method for maximizing the delignification with low energy consumption. © 2001 Society of Chemical Industry  相似文献   
48.
The fine crystal structure of Lix(Na0.5K0.5)1?xNbO3 ceramics has been studied by means of Nb-K edge extended X-ray absorption fine structure (EXAFS) and X-ray internal strain measurement technique in the vicinity of the compositions showing a polymorphic phase boundary (PPB) between orthorhombic and tetragonal structures. The anisotropic distortion of the NbO6 octahedral initially occurred when x was increased from 0.050 to 0.053, prior to the completion of the phase transition from orthorhombic to tetragonal symmetry. EXAFS clearly revealed that the bond distance of Nb–O1 with [0 0 1] configuration was increased, and that of Nb–O2 with [1 1 0] configuration was oppositely decreased in the NbO6 octahedral. In the vicinity of the PPB compositions, the internal strain η(0 1 1) also increased from 4.5 × 10?3 to the maximum value of 12.0 × 10?3 in the narrow x range from 0.040 to 0.055, then decreased to 3.2 × 10?3 at x = 0.06. On the other hand, the η(1 0 0) increases from 1.5 × 10?3 to the maximum value of 2.9 × 10?3 in the next narrow x range from 0.055 to 0.060. The variation of η(1 0 0) differed in Li dependence from that of η(0 1 1), which indicates that a large anisotropic strain remains in the crystal lattice in the PPB compositions.  相似文献   
49.
A reversed-phase ion-pair HPLC method with ultraviolet detection has been developed for determination of metoclopramide (MCP) in bovine and swine muscle, liver, kidney, fat and intestine. MCP was extracted from samples with acetonitrile, and the extracts were cleaned up on an Oasis HLB cartridge (60 mg) after liquid-liquid extraction. The limit of detection of MCP was 0.002 microg/g and the limit of quantitation was 0.007 microg/g. Recoveries of MCP spiked at 0.03 ppm ranged from 74.1 to 93.3% for bovine tissues and from 86.1 to 92.7% for swine tissues. The present method was used for the analysis of bovine and swine tissues 1 day after withdrawal following drug administration. The MCP concentrations in all tissues were lower than the Japanese provisional MRLs.  相似文献   
50.
A pectinolytic and psychrophilic yeast was isolated from soil from Abashiri, Hokkaido, Japan. The phenotype and sequencing of the 28S rDNA of the isolated strain (PPY-1) indicated a taxonomic affiliation to the basidiomycetous yeast Cystofilobasidium capitatum. C. capitatum strain PPY-1 was able to grow on two pectic compounds, polygalacturonate and pectin, at below 5 degrees C. Moreover, the extracellular fraction of the strain exhibited pectin methylesterase, pectin lyase and polygalacturonase activities at 5 degrees C. Thus strain PPY-1 may produce novel enzymes that are able to degrade pectin at low temperature, although the strain has isozymes of these enzymes.  相似文献   
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