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1.
Commercial food grade enzymes (Neutrase, calf lipase and NaturAge) were incorporated into cheese at various concentrations and ripened at 7° and 13°C. Gas chromatographic analysis indicated that free fatty acid (FFA) production increased significantly (p<0.05) with lipase and high level NaturAge. Neutrase had little effect on FFA production but showed synergistic effects with lipase. The short-chain FFA profiles were similar among control, Neutrase- and NaturAge-treated cheeses. Significant correlations (p<0.05) between C8 and C14, C16 or C18:1 and total free fatty acids were observed in all tested samples. Total concentrations of C4 and C6 may be a good indicator of flavor development during cheese ripening. Cheese with a medium level of NaturAge, ripened at 13°C for 4 wk, showed profiles of FFA similar to those of the control cheese ripened at 7°C for 12 wk.  相似文献   
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Since the damages caused by disasters associated with climate anomalies and the diversification of the social structure increase every year, an efficient management system associated with a damage assessment of the areas vulnerable to disasters is demanded to prevent or mitigate the damages to infrastructure. The areas vulnerable to disasters in Busan, located at southeastern part of Korea, were estimated based on historical records of damages and a risk assessment of the infrastructure was performed to provide fundamental information prior to the establishment of the real-time monitoring system for infrastructure and establish disaster management system. The results are illustrated by using geographical information system(GIS) and provide the importance of the roadmap for comprehensive and specific strategy to manage natural disasters.  相似文献   
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Choi S  Lee SJ  Shin JH  Cheong Y  Lee HJ  Paek JH  Kim JS  Jin KH  Park HK 《Scanning》2011,33(4):211-221
This study examined the surface nanostructures of three orbital implants: nonporous poly(methyl methacrylate) (PMMA), porous aluminum oxide and porous polyethylene. The morphological characteristics of the orbital implants surfaces were observed by atomic force microscopy (AFM). The AFM topography, phase shift and deflection images of the intact implant samples were obtained. The surface of the nonporous PMMA implant showed severe scratches and debris. The surface of the aluminum oxide implant showed a porous structure with varying densities and sizes. The PMMA implant showed nodule nanostructures, 215.56 ± 52.34 nm in size, and the aluminum oxide implant showed crystal structures, 730.22 ± 341.02 nm in size. The nonporous PMMA implant showed the lowest roughness compared with other implant biomaterials, followed by the porous aluminum oxide implant. The porous polyethylene implant showed the highest roughness and severe surface irregularities. Overall, the surface roughness of orbital implants might be associated with the rate of complications and cell adhesion. SCANNING 33: 211–221, 2011. © 2011 Wiley Periodicals, Inc.  相似文献   
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以Mo粉和Si粉为原始粉末,采用熔浆法在C/C复合材料表面原位合成了Si3N4-MoSi2/Si-SiC(MSN)系多层抗氧化涂层,借助扫描电镜和X射线衍射仪等分析手段对涂层的相组成和微观组织进行表征,并对涂层的抗氧化性能进行了初步研究.结果表明:Si浆料中添加适量Al可有效地阻止液态Si渗入C/C基材内部,3%Al-Si涂层具有最好的阻止Si渗入作用;Al含量超过3%时,Si的渗入程度随Al含量的增加而加剧;涂层中MoSi2的理论含量超过50%时,MSN-C/C复合材料1 400℃的抗氧化性能随MoSi2含量的增加而显著下降;MSN30-C/C和MSN40-C/C复合材料均在1 200~1 400℃表现出相近的抗氧化能力,但只有MSN30-C/C复合材料表现出抗1 450℃氧化的能力.  相似文献   
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The concept of “waste-to-wealth” is spreading awareness to prevent global warming and recycle the restrictive resources. To contribute towards sustainable development, hydrogen energy is obtained from syngas (CO and H2) generated from waste gasification, followed by CO oxidation and CO2 removal. In H2 generation, it is key to produce more purified H2 from syngas using heterogeneous catalysts. In this respect, we prepared Pt/Al2O3 catalyst with nanoporous structure using precipitation method, and compared its catalytic activity with commercial alumina (Degussa). Based on the results of XRD and TEM, it was found that metal particles did not aggregate on the alumina surface and showed high dispersion. Optimum condition for CO conversion was 1.5 wt% Pt loaded on Al2O3 support, and pure hydrogen was obtained after removal of CO2 gas.  相似文献   
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We propose a novel optical distribution network for multistage optical access network with multiple remote nodes (RNs) using 4skip0 filters. The system can be implemented by use of 1/spl times/N arrayed waveguide grating in the central office, cascaded RNs, and a plurality of optical network units (ONUs). It also employs colorless ONUs based on incoherent light injected Fabry-Pe/spl acute/rot laser diodes for low operation and maintenance cost. Experiment shows error-free transmission with simultaneous bidirectional 1.25 Gb/s per channel up to 20 km.  相似文献   
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In this paper, a new channel model is proposed. Since it is spatially and temporally correlated simultaneously, this new model is well consistent with the real environment of array antenna applications. The widely used sum of scattered waves and the measurement-based model have a common drawback of imperfect statistical properties, reducing the reliability of simulation results. The new model (spatially and temporally correlated fading model [STCFM]) is derived rigorously in the spatiotemporal domain so that it can provide high accuracy for the evaluation of the array antenna system. Simulation results show that direction of arrival (DOA) and angle of spread (AOS) are well defined in STCFM, BPSK with two-branch maximal ratio combining and DBPSK with differential detection are considered to verify the spatial and temporal correlation robustness of the new model, respectively. As is shown, the simulation results agree well with the theory  相似文献   
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