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排序方式: 共有271条查询结果,搜索用时 30 毫秒
81.
Motoi Sasaki Asima Sultana Masaaki Haneda Hideaki Hamada 《Topics in Catalysis》2009,52(13-20):1803-1807
Ba doped Ir/WO3–SiO2 catalysts in monolithic form showed good catalytic performance for the selective reduction of NO with CO in laboratory investigations. The addition of WO3 to SiO2 widened the active temperature range, and the role of Ba was to stabilize catalytically active Ir species. The catalyst also showed activity for NO reduction with about 45% conversion under the condition of SV <6,000 h?1 for real diesel exhaust. 相似文献
82.
Shin-ichi Satake Yoshiaki Hiroi Nobuyuki Masuda 《Computer Physics Communications》2008,179(6):404-408
Using a system of combined PC and LSI is useful when a research environment does not allow using supercomputers and calculation objects are restricted. FPGA is different from ASIC. A circuit in FPGA can be designed and reconfigured with PC or workstation electrically. We designed and implemented a circuit for 8×8 two-dimensional 2-radix FFT in a FPGA and compared its calculation speed with that of a PC. As a result, the calculation speed of the FPGA was found to be 1.3 times faster than that of a PC. 相似文献
83.
This paper describes real-time gait planning for pushing motion of humanoid robots. This method deals with an object whose mass is not known. In order that a humanoid robot pushes an unknown object in both single support phase and double support phase, real-time gait planning for pushing the unknown object is proposed. Real-time gait planning consists of zero moment point (ZMP) modification and cycle time modification. ZMP modification is the method that modifies the influence of reaction force to ZMP. By cycle time modification, the period in double support phase is modified to avoid a robot tipping over. These modifications are calculated from reaction force on arms in every cycle. With these methods, trajectory planning for pushing an unknown object in both single support phase and double support phase is calculated. Even if parameters of an object and friction coefficient on the floor vary, the robot keeps on walking while pushing an object. The effectiveness of the proposed method is confirmed by a simulation and an experiment. 相似文献
84.
Tsutomu Noguchi Hidemi Tomita Kazuki Satake Haruo Watanabe 《Packaging Technology and Science》1998,11(1):39-44
A new system of recycling expanded polystyrene has been developed which uses limonene orange oil as a solvent to recycle high grade polystyrene. Life cycle assessment was applied to this system to simulate its effect on the environment. It is shown that the new system has a lower greenhouse effect (−30%), acidification (−58%) and energy consumption (−20%) than the conventional recycling system using thermal shrinking. © 1998 John Wiley & Sons, Ltd. 相似文献
85.
In Vitro and In Vivo Digestibility of Recrystallized Amylose and Its Application for Low Glycemic Foods 总被引:1,自引:0,他引:1
Tatsuya Morita Junya Hayashi Hirofumi Motoi Takahiro Yagishita Koji Takeya Kimio Sugiyama Shuhachi Kiriyama 《Journal of food science》2005,70(3):S179-S185
ABSTRACT: To predict physiologic functions of recrystallized amylose (RCA), the true resistant starch (RS) content of RCA in the small intestine was directly measured using ileorectostomized rats where the distal ileum was anastomosed to the rectum (the cecum and colon were surgically resected together). The estimated in vivo resistant starch content of RCA was the same as the value obtained from the in vitro enzymatic RS determination (∼50%). RCA resistance to amylolytic enzymes in the small intestine was retained even after RCA incorporation into processed foods, and a bread containing 20% RCA showed a significantly lower glycemic response in rats compared with that of a control bread. Also, RCA ingestion significantly and dose-dependently decreased the body fat accretion and lowered serum concentrations of cholesterol and triglycerides in rats compared with cornstarch. These lipid-lowering effects of RCA were comparable to those obtained with high-amylose cornstarch. The restricted energy value as well as suppressed insulin response with RCA ingestion might be related to preferable changes in lipid metabolism. These nutritional properties of RCA may suggest a possible benefit as an alternative source of resistant starch for preventing diabetes, hyperlipidemia and obesity, and so on. 相似文献
86.
Masako Sato Kenichi Yoshikawa Motoi Minagawa 《Journal of the American Oil Chemists' Society》1990,67(11):711-716
The effect of builders on the stability of protease enzyme activity was studied in an effort to identify superior builders
which are soluble in water and compatible with enzymes formulated into heavy duty laundry powders. Various poly(styrenesulfonate-methacrylate)
copolymers, polyacrylate and tripolyphosphate anionic builders, as well as various poly(vinylalcohol-vinylacetate) nonionic
copolymers, namely PVAs, were used. Zeolite 4A was also used as a typical nonphosphate particulate builder in the detergents.
The protease used is frombacillus stearothermophilus. The calcium content was determined to be 16.7 mole/mole of protease by atomic spectrophotometry.
In binary systems composed of a fixed concentration of 10 U/mL protease and varied concentrations of compound, builder or
surfacant, it was found that compounds having the larger calcium ion binding capacity (C.B.C.) lowered the relative activity
of protease enzyme. The activity of protease enzyme alone was lowered about 20% by addition of 0.02% sodium dodecylbenzene
sulfonate (DBS).
The anionic builders added to the binary system of fixed 10 U/mL protease and 0.02% DBS reduce the protease enzyme activity
in proportion to the magnitude of their C.B.C. Addition of anionic builders further lowered the protease enzyme activity.
The nonionic builders and the nonionic surfactant can enhance the protease enzyme activity by protection of protease against
the inhibitor, DBS.
It is certain that calcium atoms contained in the protease must play an important role for the protease enzyme activity and
its stability. Calcium atoms must have a great influence on the formation of protease-substrate complex, protease-compound
complex and substrate-compound complex, because the protease, protein substrate and anionic compound would all be negatively
charged in alkaline solutions. Builders for enzyme-containing detergents should be constructed to be insensitive to calcium
ion. 相似文献
87.
ABSTRACT: The 3-layered fine structure of the coating of the Japanese oil-fried battered food, tempura, was observed by nuclear magnetic resonance micro imaging. The porosity of the intermediate layer was correlated to the moisture content of the batter. Chemical shift imaging, which gave moisture distribution and oil distribution images, revealed the changes in the coating after cooking. The oil was detected to a depth of only 1 mm in the outer layer immediately after frying, and its distribution slightly expanded in the surface layer with time after frying. Water quickly transferred from bean curd (tofu) as 1 ingredient, to the coating along the porous network wall within 25 min after frying. 相似文献
88.
M Kumagai-Braesch M Satake Y Qian J Holgersson E M?ller 《Canadian Metallurgical Quarterly》1998,5(2):132-145
In vitro studies of human NK cell-mediated cytotoxicity and ADCC against porcine target cells were performed. Stimulation of human PBMC responder cells with either allogeneic or xenogeneic porcine cells led to a marked increase in NK cell reactivity. Maximum reactivity was reached following 3-6 days of in vitro culture. The sensitivity of target cells ranked as follows: K562 > porcine PHA-induced lymphoblasts > resting porcine PBMC. Limiting dilution analysis showed that allo- and xeno-stimulation in vitro led to differentiation of similar frequencies of effector NK cells. Split culture experiments showed that single NK effector cells were cytotoxic against both K562 and porcine lymphoblasts, demonstrating that individual NK cells lack species specificity. NK effector cell generation stimulated by xenogeneic cells was cyclosporin A (CsA) sensitive and dependent on the presence of autologous responder T lymphocytes, a dependence that was completely reconstituted by the sole addition of human IL-2. Xenostimulation of enriched CD3+ cells also led to a preferential appearance of CD16+ or CD56+ lymphoblasts. Natural xenoreactive human anti-porcine antibodies are mainly of IgM and IgG2 subclasses, but antibodies in xenoimmunised patients reactive against porcine lymphocytes and fetal porcine islet cells were also of IgG1 and IgG3 subclasses. The same subclass distribution was found among antibodies specific for gal(alpha)1,3 gal epitopes as shown by tests performed with alpha1,3 galactosyltransferase-transfected Raji cells (human Burkitt lymphoma cells). Natural antibodies did not mediate ADCC, whereas gal(alpha)1,3 gal-specific antibodies in sera from xenoimmunised patients did. Fetal porcine islet cells were sensitive to human NK cell-mediated cytotoxicity and to ADCC mediated by xenoimmune sera. 相似文献
89.
90.
Amano T Hiro-Oka H Choi D Furukawa H Kano F Takeda M Nakanishi M Shimizu K Ohbayashi K 《Applied optics》2005,44(5):808-816
Superstructure-grating distributed Bragg reflector lasers are particularly suited for optical frequency-domain reflectometry optical-coherence tomography with wide wavelength tunability and frequency agility. We report theoretical estimates of and experimental results for the data acquisition speed, the observable depth range, the resolution, and the dynamic range of an optical frequency-domain reflectometry system that uses a superstructure-grating distributed Bragg reflector laser whose wavelength can be tuned from 1533 to 1574 nm with a tuning speed of 10 micros/0.1-nm step. 相似文献