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101.
Starch, whey or hemicellulosic waste can be used as a raw material for the industrial production of rare sugars. D-glucose from starch, whey and hemicellulose, D-galactose from whey, and D-xylose from hemicellulose are the main starting monosaccharides for production of rare sugars. We can produce all monosaccharides; tetroses, pentoses and hexoses, from these raw materials. This is achieved by using D-tagatose 3-epimerase, aldose isomerase, aldose reductase, and oxidoreductase enzymes or whole cells as biocatalysts. Bioproduction strategies for all rare sugars are illustrated using ring form structures given the name Izumoring. 相似文献
102.
Prostate and colorectal cancers are among the most common cancers and identifying modifiable risk factors are important steps to reduce the burden of these severe diseases. Results from several but mostly small observational studies as well as the secondary analysis of an intervention trial provide support for a chemopreventive effect of selenium on prostate and colorectal cancers. Results suggest effect modification by gender and smoking, but this interpretation is limited by the statistical power of previous studies. Several cancer preventive mechanisms have been described and it is likely that selenium acts through multiple pathways. In particular, the anti-oxidative and anti-inflammatory effects mediated through activity of selenoenzymes are discussed, given the relevance of oxidative stress and inflammation in these cancers. Genetic variation in selenoenzymes may modify the potential chemopreventive effect of selenium and need to be further investigated. Additional large observational studies using biomarkers of selenium intake and intervention trials, such as the Selenium and Vitamin E Cancer Prevention Trial, will be important to further evaluate the potential chemopreventive effect of selenium. Furthermore, characterization of functional effects of polymorphisms in selenoenzymes is needed. 相似文献
103.
Skin permeation of amino acids through excised rat skin was measured at various pH values. The permeabilities varied with the donor pH and amino acid, indicating that each ionic species of amino acid may have a different permeability. The permeability coefficient of each ion was estimated from the permeability-pH profiles using the dissociation constants. The estimated values for mono-cation and uncharged zwitterion were not dependent on the lipophilicity but on the size of the amino acid, suggesting a porous mechanism of transport. The permeability coefficient was highest for di-cation, followed by mono-cation, positively charged, uncharged and negatively charged zwitterions. The electrical potential difference across the skin was too small to affect the permeation of ions. The permselective property of skin thus seems to be determined by the difference of diffusivity in aqueous pores of skin due to the hydration of ions and other factors. 相似文献
104.
Motoshi Tanaka Naru Takata 《IEEJ Transactions on Electrical and Electronic Engineering》2021,16(3):488-490
In order to develop a detection system of abnormal situations (such as accidents) for a person living alone, SOM (self-organizing map) of only daily activity sound recorded with a broadband microphone, and detection of abnormal situation are investigated. The SOM was divided into three regions containing 98.9, 1.0, and 0.1% of the number of learned vectors, and transition of the vectors of simulated abnormality sound was observed. The result indicates the feasibility of use of the SOM for detecting abnormal situations. © 2021 Institute of Electrical Engineers of Japan. Published by Wiley Periodicals LLC. 相似文献
105.
Dr. Riku Kawasaki Hidetoshi Hirano Keita Yamana Ayano Oshige Kotaro Nishimura Nanami Kono Dr. Yu Sanada Kaori Bando Anri Tabata Naoki Yasukawa Dr. Hideki Azuma Takushi Takata Dr. Yoshinori Sakurai Prof. Hiroki Tanaka Prof. Minoru Suzuki Dr. Naoki Tarutani Prof. Kiyofumi Katagiri Prof. Takeshi Nagasaki Prof. Atsushi Ikeda 《Chembiochem : a European journal of chemical biology》2023,24(15):e202300186
Minimally invasive boron neutron capture therapy (BNCT) is an elegant approach for cancer treatment. The highly selective and efficient deliverability of boron agents to cancer cells is the key to maximizing the therapeutic benefits of BNCT. In addition, enhancement of the frequencies to achieve boron neutron capture reaction is also significant in improving therapeutic efficacy by providing a highly concentrated boron agent in each boron nanoparticle. As the density of the thermal neutron beam remains low, it is unable to induce high-efficiency cell destruction. Herein, we report phospholipid-coated boronic oxide nanoparticles as agents for BNCT that can provide a highly concentrated boron atom in each nanoparticle. The current system exhibited in vitro BNCT activity seven times higher than that of commercial boron agents. Furthermore, the system could penetrate cancer spheroids deeply, efficiently suppressing thermal neutron irradiation-induced growth. 相似文献
106.
A membrane precursor was prepared by the copolymerization of p-styrenesulfonyl chloride and divinylbenzene in the presence of a poly(vinyl chloride) supported cloth. The surface of the membrane was treated with various amines, and then the sulfonyl chloride groups in the internal part of the membrane were hydrolyzed with an aqueous sodium hydroxide solution in organic methanol or acetone solvent. Hydrolysis conditions were examined for the introduction of the sulfonic acid groups. The membrane modified by ethylenediamine exhibited slightly bipolar properties during the electrodialysis of seawater. Surface-modified membranes using tetraethylenepentamine exhibited excellent monovalent cation permselectivity, low membrane electric resistance, and long performance durability during the electrodialysis of seawater. 相似文献
107.
The effects of absorbed water on the interfacial fracture resistance between two layers of unsaturated polyester (UP) and glass of the bilayer specimen were evaluated by measuring a load for producing the fracture by inserting a razor blade into the interface. The specimens were subjected to the cyclic absorption-desorption and the continuous absorption processes of water. The load to initiate the interfacial fracture was markedly lowered by the early absorption process for short period, and then gradually reduced with increasing cycle or period of water absorption, although it slightly recovered after the first great reduction when the specimens were subjected to the soaking process at lower temperatures. The micro-FTIR (ATR) analyses of the detached surface of the UP resin from the glass plate revealed that the water is accumulated in the resin at the interface in the cluster, showing the concentration to increase with increases both in the temperature of environmental water and in the water-soaking period. The IR analyses also demonstrated the hydrolysis reaction to take place on the detached resin surface of specimen exposed to water at high temperature. Thus the accumulated water at the interface may remain and promote the interfacial degradation even under the drying process by various mechanisms like the hydrolysis reaction in hot water environment. 相似文献
108.
Formation process of ultrafine grained ferrite through a simple thermomechanical route composed of cold-rolling and annealing of dual-phase starting microstructures was investigated. A 0·1%C steel having a ferrite–martensite dual-phase microstructure was cold-rolled by 91% and subsequently annealed below the eutectoid (A1) temperature. During the annealing, the cold-rolled microstructure gradually changed to be equiaxed ultrafine ferrite, without preferential growth of particular ferrite grains. Hardness of the cold-rolled specimen continuously decreased without a significant drop. The main components of texture in the cold-rolled specimen, α-fibre and γ-fibre, did not change greatly after the formation of ultrafine grains. It was suggested that finely subdivided region having large misorientations in the cold-rolled state grew with recovery to form the ultrafine ferrite. 相似文献
109.
H Ito T Takekoshi M Miyauchi I Ogawa T Takata H Nikai K Takemoto 《Canadian Metallurgical Quarterly》1998,43(9):741-744
Despite the reducing exposure to allogeneic blood in cardiac surgery, most of patients with anemia still require allogeneic blood. In this study, we have attempted to harvest the blood from cardiac patients with baseline hemoglobin levels below 11.0 g/dl using recombinant human erythropoietin (rHuEPO). 29 anemic patients undergoing cardiac surgery at our hospital between January 1994 and March 1997 were divided into two groups: 3 weeks' treatment with recombinant human erythropoietin (rHuEPO) and blood donation (group 1, n = 15) and iron supplementation alone (group 2, n = 14). There were no statistically significant differences among the two groups in patients characteristic and surgical data. No serious adverse events after phlebotomy were apparent in patients donating autologous blood. Patients in group 1 had significantly higher hemoglobin levels than patients in group 2 at 7 days before operation. The number of reticulocytes were increased at just before operation in group 1, whereas group 2 showed no significant increase. The estimated hemoglobin increase in group 1 were higher at 7 days and just before operation. In 75% of group 1, allogeneic blood transfusion could be avoided, while all patients in group 2 received allogeneic blood transfusion. This study suggests that the combination of rHuEPO administration and autologous blood donation would be beneficial for anemic patients in elective cardiac surgery. The use of rHuEPO should not be restricted to anemic patients. 相似文献
110.
T Takata JA D'Errico KB Atkins JE Berry C Strayhorn RS Taichman MJ Somerman 《Canadian Metallurgical Quarterly》1998,69(11):1247-1255
Proteins associated with the mineral phase of dentin are considered to have the potential to alter cell function within the local environment, during development and regeneration of tooth/periodontal tissues. Cells that may be altered include osteoblasts, ameloblasts, periodontal ligament cells, odontoblasts, and cementoblasts. However, specific factors within dentin controlling cell activity have not been elucidated. To investigate further the role of dentin proteins in regulating cell behavior, MC3T3-E1 cells, a mouse osteoprogenitor cell line, were exposed to guanidine/EDTA extracts of dentin (G/E-D) prepared from bovine teeth. Cells, with or without G/E-D (2 to 50 microg/ml), were evaluated for proliferative activity and for mRNA expression of bone-associated genes. Results indicated that G/E-D suppressed cell proliferation and caused striking morphological changes, including the conversion of cuboidal cells into fibroblastic, spindle-shaped cells. Markers of osteoblast differentiation, osteocalcin and bone sialoprotein mRNA were decreased, while osteopontin mRNA was enhanced in cells exposed to G/E-D. Since transforming growth factor beta (TGFbeta1) has been reported to influence cells in a similar fashion, G/E-D were examined for the presence of and concentration of TGFbeta using slot blot analysis and enzyme immunoassay (ELISA), respectively. These analyses demonstrated that G/E-D contained 6.6 ng/mg of TGFbeta1. Next, cells were exposed to G/E-D in conjunction with anti-TGFbeta1,2,3 antibody. When cells were exposed to antibody, G/E-D-mediated changes in morphology and gene expression were blocked. These results suggest that TGFbeta1 and perhaps other factors in dentin can regulate cell behavior and, therefore, can influence development, remodeling, and regeneration of mineralized tissues. 相似文献