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31.
Burcu Çabuk 《Drying Technology》2013,31(10):1223-1233
In this study, whey protein isolate-pullulan (WP/pullulan) microspheres were developed to entrap the probiotic Lactobacillus acidophilus NRRL-B 4495 by spray-drying technique. Microcapsules were analyzed for physicochemical characteristics including morphology, particle size, moisture content, water activity, dissolution time, and color properties. Results revealed that microcapsules were spherical in shape and obtained particle sizes between 5 and 160 µm, with an average size of around 50 µm. Blending pullulan with WP provided enhanced survival of probiotic bacteria during spray drying with a final viable cell number of 8.81 log CFU/g of microcapsule. Encapsulated probiotics were also found to have significantly (p ≤ 0.05) higher survived cell numbers compared to free probiotics under detrimental gastrointestinal conditions. Moreover, dissolution analysis suggested that protein-polysaccharide powdered microcapsules showed pH-sensitive dissolution properties in simulated gastric juice and simulated intestinal juice.  相似文献   
32.
In this study, starch‐based hybrid electrospun nanofiber meshes were fabricated by electrospinning. Spinning solutions were prepared by mixing starch and certain amounts of poly(ethylene‐alt‐maleic anhydride). Starch‐based nanofiber meshes became insoluble in water with thermal‐induced esterification of hydroxyl groups onto starch backbone. Morphologic and structure analysis of the electrospun nanofiber meshes were investigated by scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR) techniques. Thermal properties of nanofiber meshes were characterized by thermal gravimetric analysis (TGA) and differential scanning calorimetry (DSC). Thermal stability of nanofiber meshes were increased with formation of intermolecular bonds between starch and poly(ethylene‐alt‐maleic anhydride). POLYM. COMPOS. 34:1321–1324, 2013. © 2013 Society of Plastics Engineers  相似文献   
33.
The present study was conducted to determine macroanatomic characteristic as well as light and electron microscopic examination (SEM) of pecten oculi and totally 20 bulbus oculi belonging to 10 seagulls (Larus canus) were used. Pecten oculi formations consisted of 18 to 21 pleats and their shape looked like a snail. Apical length of the pleats forming pecten oculi were averagely measured as 5.77 ± 0.56 mm, retina‐dependent base length was 9.01 ± 1.35 mm and height was measured as 6.4 ± 0.62 mm. In pecten oculi formations which extend up to 1/3 of the bulbus oculi, two different vascular formations were determined according to thickness of the vessel diameter. Among these, vessels with larger diameters which are less than the others in count were classified as afferent and efferent vessels, smaller vessels which are greater in size were classified as capillaries. Furthermore, the granules which were observed intensely in apical side of the pleats of pecten oculi were observed to distribute randomly along the plica.  相似文献   
34.
Building information models (BIMs) are maturing as a new paradigm for storing and exchanging knowledge about a facility. BIMs constructed from a CAD model do not generally capture details of a facility as it was actually built. Laser scanners can be used to capture dense 3D measurements of a facility's as-built condition and the resulting point cloud can be manually processed to create an as-built BIM — a time-consuming, subjective, and error-prone process that could benefit significantly from automation. This article surveys techniques developed in civil engineering and computer science that can be utilized to automate the process of creating as-built BIMs. We sub-divide the overall process into three core operations: geometric modeling, object recognition, and object relationship modeling. We survey the state-of-the-art methods for each operation and discuss their potential application to automated as-built BIM creation. We also outline the main methods used by these algorithms for representing knowledge about shape, identity, and relationships. In addition, we formalize the possible variations of the overall as-built BIM creation problem and outline performance evaluation measures for comparing as-built BIM creation algorithms and tracking progress of the field. Finally, we identify and discuss technology gaps that need to be addressed in future research.  相似文献   
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In an experimental study on fracture properties of hybrid fibre concrete, specimens with varying fibre content (mixtures of short and long fibres) were loaded in uniaxial tension. Dog-bone shaped specimens of four different sizes in a size range of 1:8 were tested. Focus of the study was the determination of the size effect on nominal strength and fracture processes. A vacuum impregnation technique was used to investigate the fracture process. Experiments showed that multiple cracks, which formed before the peak, localised into one major crack beyond peak. Multiple cracking could be obtained by increasing the amount of thin short fibres whereas the large fibres can enhance the bridging of localised macrocracks. With decreasing strength, the size effect on the strength appears to increase. It is observed that the size effect on nominal tensile strength decreases with increasing material ductility. Preliminary analysis of the results showed that the observed size effect can be considered as a combination of statistical and structural size effects.  相似文献   
38.
Selective recognition of proteins by synthetic molecularly imprinted polymers is one of the interesting topics in biosciences. Carnosine (β-alanyl-l-histidine) and related histidine containing peptides are distributed in a wide range of tissues in vertebrate organisms. These peptides have been extensively studied because of their important physiological properties besides their metal chelation property. In this study, preparation of carnosine specific imprinted polymers (MIPs) for the recognition of imidazole containing peptides with and without copper ion is reported. Carnosine and copper–carnosine complex were employed as template molecules where 4-vinylpyridine and ethylenglycol dimethacrylate were chosen as monomer and crosslinker, respectively. The selectivity and binding studies of copper–carnosine imprinted polymer showed high selectivity toward both carnosine (template peptide) and the cupric ion. The selectivity of copper–carnosine imprinted polymer was 65% and carnosine imprinted polymer was approximately 40%. These results indicate that specific recognition of carnosine is depending on the basis of metal coordination  相似文献   
39.
This paper systematically explores the effects of firms’ innovation activities on their productivity changes for Turkish manufacturing firms, differentiating between different typologies of innovation. We employ endogenous switching methodology, controlling for endogeneity and selection bias issues, as well as analysing counterfactual scenarios. The main finding of the study points to firm heterogeneity in terms of propensity both to innovate and to benefit from innovation activities. Our results indicate that all types of innovation activity have positive effects on the productivity of firms when compared with non-innovating firms. We find robust evidence for the differential impact of innovation on firm productivity across different innovation types. Further, this relationship alters across different phases of the economy with respect to the 2008 financial crisis.  相似文献   
40.
Journal of Materials Science: Materials in Electronics - Zinc oxide (ZnO) rods film was fabricated by homemade and simple spray pyrolysis technique on a p-type silicon (Si) substrate, and the film...  相似文献   
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