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121.
122.
Yoshio Tsuchiya Kikuo Sumi 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》1967,17(12):364-366
When plastics are involved in a fire they may yield toxic decomposition products. Some quantitative data on the decomposition products of plastics are available in the literature, but it is difficult to assess the danger from the different amounts of various products because of the absence of a suitable method of evaluation. The authors have proposed a method of evaluation based on pyrolysis followed by gas chromatographic analysis and have used it to assess toxicity from various thermal decomposition products of polyvinyl chloride. Hydrogen chloride was found to be the main toxic decomposition product. 相似文献
123.
Bin Xia . I. Wuled Lenggoro Kikuo Okuyama 《Journal of the American Ceramic Society》2001,84(7):1425-1432
The preparation of nickel powders by the ultrasonic spray pyrolysis of Ni(HCOO)2 was studied. Phase-pure nickel powder was obtained at as low as 350°C. HCOOH was a reducing source for nickel formation. Moreover, metallic nickel was obtained at a residence time as short as 0.1 s at 600°C. A broad range of particle morphologies, which included agglomerated nanoparticles, nonagglomerated submicrometer particles, hollow particles, and spherical dense particles, were obtained from Ni(HCOO)2 pyrolysis and were shown to depend on the precursor solution and the operating condition. 相似文献
124.
Sunao Miyashita Isamu Satoh Makoto Yanaga Kenji Okuno Hideo Suganuma 《Progress in Nuclear Energy》2008,50(2-6):499-503
A new solvent-extraction technique based on in situ formation of dithiocarbamate derivatives in order to separate Am(III) from Eu(III) was carried out. In this technique, the extractant is formed during the extraction course by the reaction between the organic materials, which are needed to synthesize the extractant. The synthesis of extractant in in situ extractant-formation method was carried out as follows. Di-substituted amine, such as dioctylamine (DOA), dibenzylamine (DBzA) and so on, and carbon disulfide (CS2) were mixed in organic solvents, such as nitrobenzene, to produce dioctylammonium dioctyldithiocarbamate (DOA+·DODTC−), dibenzylammonium dibenzyldithiocarbamate (DBzA+·DODTC−), or so on. These organic solutions are also the organic phase in the solvent extraction, whereas the aqueous phase is 1.00 mol/dm3 (H, Na)NO3 solution. The elements of Am(III) and Eu(III) were extracted into organic phase from different hydrogen ion concentrations of aqueous phase. The SF of Am(III)/Eu(III) is 3.2 × 104 at pHeq = 6.25 in DOA–CS2/nitrobenzene system. This separation technique of Am(III) from Eu(III) by extraction based on in situ extractant formation has the following advantages. (a) It is unnecessary to take the chemical stability of extractant into account for storage purpose, and (b) Am(III) can be completely separated from Eu(III) by a single extraction procedure. 相似文献
125.
Kosuke Tanaka Isamu Sato Ken Kurosaki Shinsuke Yamanaka 《Journal of Nuclear Materials》2011,414(2):316-319
Polycrystalline specimens of barium plutonate, BaPuO3, have been prepared by mixing the appropriate amounts of PuO2 and BaCO3 followed by reacting and sintering at 1600 K under the flowing gas atmosphere of dry-air. The sintered specimens had a single phase of orthorhombic perovskite structure and were crack-free. The Debye temperature of BaPuO3 was determined from the sound velocity and lattice parameter measurements. The elastic moduli were also determined from the longitudinal and shear sound velocity. The thermal conductivity of BaPuO3 was calculated from the measured density at room temperature, literature values of heat capacity, and thermal diffusivity measured by a laser flash method in vacuum. The thermal conductivity of BaPuO3 was roughly independent of the temperature and was almost the same magnitude as that of BaUO3. This was markedly lower than the conductivities of other perovskite type oxides and was about one-tenth that of UO2 around room temperature. The temperature dependence of the thermal conductivity of BaPuO3 was found to be quite similar to that of BaUO3. 相似文献
126.
The biological dosemeter that measures biological responses to ionising radiation is useful for radiation protection. This paper presents the development and characterisation of a gamma ray irradiation dosimetry system based on real-time PCR (polymerase chain reaction) methodology. Real-time PCR is used to amplify and simultaneously quantify a targeted DNA molecule. If there are no limitations due to limiting substrates or reagents, at each extension step, the amount of DNA target is doubled, leading to exponential (geometric) amplification of the specific DNA fragment. The essential point of this assay is that DNA lesions caused by ionising radiation block DNA synthesis by DNA polymerase, resulting in a decrease in the amplification of a damaged DNA template compared with that of non-damaged DNA templates. 相似文献
127.
Furuse H Yabe I Asakura T Miyawaki O Toda K 《Journal of Bioscience and Bioengineering》2003,95(5):544-547
The culture fluid of the fungus Aureobasidium pullulans and the exopolysaccharide solution obtained by removal of the microbial cells exhibit a marked shear dependence of viscosity. The viscosity in a high shear rate region was a little higher than that predicted by a non-Newtonian viscosity equation derived previously on the basis of the concept of traveling force. In a sample exhibiting such high shear rate dependence, a hydrodynamic effect based on the fluid structure of the binding of contacting polymers and suspended microbial cells on viscosity becomes comparatively significant. A model for the shear rate dependence of the viscosity is needed to elucidate the mechanism of the viscosity behavior. A term concerning the increase in viscosity caused by the binding of polymers and the microbial cells suspended in a medium was added to the previous viscosity equation. The experimental shear dependence of the viscosity was well simulated by the modified viscosity equation. 相似文献
128.
Humans are exposed to ubiquitous phthalates via multiple pathways. Exposures to phthalates have been estimated in some previous risk assessments in Japan based on point-of-contact measurement or scenario evaluation approaches. While the Japanese national government has regulated the use of di(2-ethylhexyl)phthalate (DEHP) and excluded several other phthalates from its regulation based on some of them, it is unclear whether such past exposure assessment studies fully assessed total human exposure to phthalates. In the present study, we measured their urinary metabolites, which show direct evidence of human exposure to phthalates. We recruited voluntary participants (N = 36) who agreed to donate urine samples, and measured the urinary concentrations of phthalate metabolites using enzymatic deconjugation, solid-phase extraction, and high-performance liquid-chromatography isotope-dilution tandem mass spectrometry. We then derived the daily intakes of their respective phthalates based on steady state assumption and finally compared them with the corresponding estimated daily intakes of each phthalate via diet and air derived from previous exposure or risk assessments in Japan. These comparisons showed that exposures to dimethyl phthalate, diethyl phthalate, and di-n-butyl phthalate via diet and air accounted for less than half of their respective total exposures. On the other hand, it appears that dietary intake was more predictive for the total exposure to n-butyl-benzyl phthalate and DEHP. The probabilities that the log normal distribution of each phthalate daily intake estimated from the present study exceeds the corresponding tolerable daily intake were estimated to be less than 10(-4). 相似文献
129.
130.
Polycrystalline silicon (poly-Si) films have been deposited on glass substrates by a layer-by-layer technique at very low temperature, 300°C, using fluorinated precursors. The electronic transport was characterized by Hall effect and conductivity measurements over a wide temperature range, 100 K to 400 K. The structure of the materials is a function of the film thickness. The measured Hall mobility increases as the thickness increases. The Hall mobility Arrhenius plot shows linear dependence with a negative slope over the temperature range examined, suggesting that carrier conduction is limited by grain boundary barriers. 相似文献