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排序方式: 共有388条查询结果,搜索用时 7 毫秒
381.
For emission control of volatile organic compounds (VOC), e.g., in the painting and printing industries, conventional Pt/Al2O3 and Co3O4‐CeO2 catalysts are used. On the Pt/Al2O3 catalyst, aromatic hydrocarbons containing a benzene ring such as toluene can be oxidized at a lower complete oxidation temperature than on Co3O4‐CeO2, under typical treatment conditions. However, ethyl acetate and isopropyl alcohol can be oxidized at a lower complete oxidation temperature on Co3O4‐CeO2 than on Pt/Al2O3. In this study, platinum was directly supported on Co3O4‐CeO2. Using chloroplatinic acid, the platinum cohered and the catalytic activity did not improve. But when the platinum was supported using platinum colloid coated with dispersant, high‐dispersion support of the platinum on the Co3O4‐CeO2 surface was achieved, and toluene, ethyl acetate, and isopropyl alcohol could be oxidized at less than 250 °C. 相似文献
382.
Songhak Yoon Jürgen Dornseiffer Theo Schneller Detlev Hennings Shoichi Iwaya Christian Pithan Rainer Waser 《Journal of the European Ceramic Society》2010,30(2):561-567
BaTiO3–Ni nanopowders have been synthesized via an alkoxide-mediated synthesis route through the hydrolysis and condensation of barium hydroxide octahydrate and titanium (IV) isopropoxide in the presence of submicron sized, spherical Ni particles originating from a commercial Ni paste, that was introduced during the preparation procedure. X-ray diffraction (XRD) patterns indicate that nanocomposite powders of the phases BaTiO3 and Ni could be successfully prepared and tailor-made composition control was confirmed. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) show that the synthesized BaTiO3 nanoparticles were aggregates of nanosized primary particles as small as 40 nm in diameter. The average Ni particle size was estimated to be about 200 nm. Dilatometric measurements on green compacts of these powders revealed that the shrinkage of BaTiO3–Ni composites is retarded compared to both, pure BaTiO3 and Ni. Thermogravimetric analysis (TGA) shows weight losses due to the decomposition of organic binder from Ni paste, the release of water from the surface and of hydroxyl ions from inside the lattice of the BaTiO3 nanoparticles. With the addition of nickel, the dielectric constant increased slightly due to the percolation effect. 相似文献
383.
Prevalence of Cryptosporidium oocysts and giardia cysts in the drinking water supply in Japan 总被引:11,自引:0,他引:11
A one-year monitoring of Cryptosporidium oocysts and Giardia cysts was conducted at a water purification plant. A total of 13 samples of 50 L river source water and 26 samples of 2,000 L-filtered water, treated by coagulation flocculation, sedimentation and rapid filtration, were tested. Prior to conducting a survey of a water purification plant, we developed a method for concentrating Cryptosporidium oocysts from a large volume of raw or filtered water using a hollow fiber ultrafiltration (UF) membrane, and this procedure was adapted to survey a water purification plant. Cryptosporidium oocysts were detected in all of the 13 raw water samples. The geometric mean concentration was 40 oocysts 100 L. Giardia cysts were detected in 12 of 13 raw water samples (92%) and the geometric mean concentration was 17 cysts/100 L. Probability distributions of both Cryptosporidium oocyst and Giardia cyst concentration in raw water were nearly lognormal. In filtered water samples, Cryptosporidium oocysts were detected in 9 of the 26 samples (35%) with the geometric mean concentration of 1.2 oocysts /1,000 L and Giardia cysts in 3 samples (12%) with 0.8 cysts/1,000 L. The estimated log10 removal efficiency of Cryptosporidium oocysts and Giardia cysts by rapid-sand filtration was 2.47 and 2.53, respectively. Empty particles were removed at a higher log10 than intact oocysts and cysts. The efficiency of particle removal in the rapid sand filtration process tends to be reduced under cold-water conditions. Close management is necessary in the winter when the water temperature is low. 相似文献
384.
Hironori Mitake Kazuyuki Asano Takafumi Aoki Salvati Marc Makoto Sato Shoichi Hasegawa 《Computer Graphics Forum》2009,28(2):279-287
Various forms of art and entertainment involve many different characters, and advances in human interfaces have necessitated physical interactions in order to develop an improved sense of reality. In this paper we propose a method for generating the motions of characters using multidimensional keyframe animation in parallel with real-time physical simulation. The method generates characters capable of physical interaction, and also allows animators to use traditional methods for designing character motion. We have implemented the system and confirmed its effectiveness experimentally. 相似文献
385.
Masayuki Fujimoto Yuji Nishi Toshimasa Suzuki Hisashi Shigetani Shoichi Sekiguchi 《Journal of the American Ceramic Society》1998,81(9):2477-2480
Coherent copper-metal precipitates at grains adjacent to the Σ= 5 coincident-site lattice (CSL) boundary in a low-temperature-fired Ni-Zn-Cu ferrite have been observed and analyzed using analytical electron microscopy. This precipitation behavior is related to the copper solubility limits in the Ni-Zn-Cu ferrite during cooling after sintering, and preferential solute segregation may be dominant at stacking faults rather than at the Sigma = 5 CSL boundary. Copper-metal precipitates have a 〈100〉 matrix ∥〈100〉 Cu coherent relationship to the ferrite matrix. 相似文献
386.
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388.
The effect of concentration of tapioca maltodextrin with three different DE values on the viscosity, depletion attraction potential (Wdep), rate of coalescence (Kc), and creaming rate of oil‐in‐water emulsion have been investigated. The relative viscosity and Wdep increased with increasing maltodextrin concentration. Critical flocculation concentration (CFC) of emulsions containing maltodextrin with DE of 16 (DE16), 12 (DE12), and 9 (DE9) were 11, 7, and 5.5 wt%, respectively. At maltodextrin concentrations below CFC, there was no change in Kc and no creaming was observed. At maltodextrin concentrations above CFC, an increase in the concentration of DE9 and DE12 resulted in an increase in Kc until it reached a constant value. Kc values remained to be constant in the concentration range between 30 and 40 wt% for DE9 and that between 35 and 45 wt% for DE12. Further increasing in concentration of DE9 and 12 decreased Kc. Kc of DE16 monotonically increased with increasing concentration from CFC to 50 wt%. The rate of creaming decreased with increasing maltodextrin concentration over CFC until it reached zero. Creaming was not observed at maltodextrin concentrations more than 35 wt% for DE9 and 40 wt% for DE12 whereas DE16 showed creaming at all concentrations above CFC. A maltodextrin with a lower DE inhibited creaming more efficiently than maltodextrin with a higher DE because of higher viscosities. The Kc tended to increase with decreasing DE because the strength of interaction between oil droplets increased. 相似文献