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951.
An  Mirae  Oh  Miae  Park  Keun-Tae  Seon  Ki Hwan  Jo  Jeong Eun  Lee  Seong Kweon  Kim  Jeong-Keun  Shin  Kwang Soon  Koh  Jong-Ho  Lim  Young-Hee 《Food science and biotechnology》2021,30(9):1257-1268
Food Science and Biotechnology - Respiratory immunity is getting more important recently due to outbreak of respiratory diseases and increasing the concentration of fine dust. The aim of this study...  相似文献   
952.
Food Science and Biotechnology - We aimed to investigate the effect of high pressure treatment (HPT) on the physical properties of surimi sausages. For protein gelation, high hydrostatic pressure...  相似文献   
953.
Lysozyme from Filipino venus (Ruditapes philippinarum) was purified by ion-exchange and gel filtration chromatography. The purification fold and yield were 3,402 and 32.4%, respectively. The molecular weight was determined to be 13.4 kDa by SDS-PAGE. The specific activity of lysozyme was 3.76×105 units/mg protein with Micrococcus lysodeikticus as a substrate. The optimum temperature and pH of lysozyme were 75°C and 5.5, respectively. Lysozyme activity was decreased with about 45% after heat treatment for 30 min at 80°C, and completely inactivated at 100°C. It was activated by NaCl (10–70 mM), MgCl2, and CaCl2 (2–5 mM) whereas it was inhibited by ZnCl2 (2–30 mM).  相似文献   
954.
Carcass chilling during broiler processing is a critical step in preventing growth of pathogenic and spoilage bacteria. The objective of this study was to compare the microbiological quality of air- and water-chilled broiler carcasses processed at the same commercial facility. For each of four replications, 15 broilers were collected from the same commercial processing line after evisceration, after spraying with cetylpyridinium chloride (a cationic disinfectant), and after air chilling or water immersion chilling (WIC). All carcasses were quantitatively examined for mesophilic aerobic bacteria, Escherichia coli, coliforms, and Campylobacter as well as for the presence of Salmonella and Campylobacter. No significant differences (P > 0.05) were seen between air and water chilling for E. coli or coliforms or for the incidence of Salmonella and Campylobacter. Lower numbers of Campylobacter were recovered from WIC than from air-chilled carcasses (P < 0.05), but the incidence of Campylobacter on WIC carcasses was similar, suggesting that some Campylobacter organisms were injured rather than killed during WIC. In-line spraying with the disinfectant effectively decreased the incidence of Salmonella and Campylobacter on prechilled carcasses; however, cells presumably injured by the sanitizer recovered during chilling. Therefore, on-farm intervention strategies remain critically important in minimizing the spread of microbial contaminants during processing.  相似文献   
955.
Rosmarinic acid (RA) has a number of interesting biological activities, e.g. anti‐viral, anti‐bacterial, anti‐inflammatory and antioxidant. The antioxidant activity of RA is stronger than that of vitamin E. Despite its strong antioxidant activity, it was limited to use in cosmetics because of the low water solubility, discolouration and chemical instability. The purpose of this study was to prepare RA‐loaded polycaprolactone (PCL) microspheres using emulsion solvent evaporation method and characterize them with different surfactants used in the formation process. Finally, long‐term stability of RA was evaluated in the cosmetic formulation. As a result, PCL microspheres were found to be spherical in shape, with zwitterionic surfactant‐PCL particles being the smallest size distribution and highest entrapment efficiency of RA. Emulsions containing RA‐loaded PCL microspheres showed a better long‐term stability of the RA compared with those containing only RA. These results suggest that RA may be stably and efficiently encapsulated into polycaprolactone microspheres.  相似文献   
956.
The purposes of this study were to determine the inactivation effects of intense pulsed light (IPL) on Listeria monocytogenes and the commercial feasibility of this sterilization method. The inactivation of L. monocytogenes at cultivated plates increased with increasing electric power and treatment time. Approximately 4–5 log reduction of the cell was achieved with IPL treatment for 5000, 600, 300, and 100 μs at 10, 15, 20, and 25 kV of voltage pulse, respectively. In the early stages of IPL treatments at 10, 15, and 20 kV, little inactivation was observed with a critical treatment time (tc) of 360.6, 95.5, and 32.2 μs, respectively, while an abrupt inactivation without a critical treatment time was observed at 25 kV. The sterilization effects on commercial infant foods inoculated with L. monocytogenes were investigated at 15 kV, which showed higher energy efficiency for the inactivation of L. monocytogenes.  相似文献   
957.
To control the spread of bovine spongiform encephalopathy in cattle through contaminated animal feedstuffs, screening of feed products is essential. We designed five pairs of primers to identify specifically raw and heat-treated tissue from cattle, sheep, goat, deer, and ruminants in general. A forward common primer was designed based on a conserved DNA sequence in the mitochondrial 12S rRNA-tRNA(val)-16S rRNA gene, and reverse primers were designed to hybridize with a species-specific DNA sequence for each species considered. All primers were developed to create a specific PCR product small enough (less than 200 bp) to be suitable for heat-treated material. To evaluate the effect of heat treatment, a severe sterilization condition (133 degrees C at 300 kPa for 20 min) was chosen. Species-specific amplicons were obtained from all types of heat-treated meat meals. Analysis of laboratory-contaminated vegetable meals revealed that the detection limit of the assay was 0.05% for each species analyzed. This PCR-based analysis can be used as a routine method for detecting banned animal-derived ingredients in raw and heat-treated feedstuffs.  相似文献   
958.
The antioxidant activities of peanut (Arachis hypogaea L.) hull extracts were evaluated after far-infrared (FIR) radiation or heat treatment. Peanut hulls in petri dishes were FIR-irradiated or heat-treated (150 °C) for 5, 10, 15, 20, 40 or 60 min. The water extracts (300 mg/10 mL) of peanut hulls (WEPH) were prepared and their total phenol contents (TPC), radical scavenging activity (RSA), and reducing power were determined. The antioxidant activities of WEPH increased as the time of heating or FIR-radiation increased. When peanut hulls were FIR-irradiated at 150 °C for 60 min, the values of TPC, RSA, and reducing power of WEPH increased from 72.9 to 141.6 μM, 2.34% to 48.83%, and 0.473 to 0.910, respectively, compared to the untreated controls. Heat treatment of peanut hull under the same conditions (150 °C for 60 min) also increased the TPC, RSA, and reducing power of WEPH from 72.9 to 90.3 μM, 1.90% to 23.69%, and from 0.471 to 0.718, respectively. The result indicated that FIR-radiation or heat treatment on peanut hulls increased the antioxidant activities of WEPH.  相似文献   
959.
The overall goal of this study was to develop a set of process design principles for low-energy X-ray irradiation of tree nuts. Almonds and walnuts were inoculated with Salmonella Enteritidis PT30 and Salmonella Tennessee, and conditioned to four different water activities (0.23, 0.45, 0.64, and 0.84 aw). Thereafter, the inoculated/conditioned samples were irradiated to achieve up to a 5-log reduction in Salmonella using a pilot scale low-energy X-ray food irradiator. Greater efficacy (D10-value: the dose required to eliminate 90% of the microbial population) for inactivating SE PT30 and S. Tennessee was seen on the surface of almonds (0.226-0.431 kGy) than on walnuts (0.474-0.930 kGy) at all water activities. Also, the efficacy did not change monotonically with water activity. Overall, no significant difference (P > 0.05) in sensory characteristics was seen between non-irradiated almonds and those irradiated to achieve a 5 log reduction in Salmonella. However, irradiating walnuts to the dose corresponding to a 5 log reduction caused a perceivable change in flavor. Post-irradiation storage tests revealed that surviving bacterial counts did not change over 120 days, regardless of nut type, Salmonella serovar, and aw. Therefore, low-energy X-ray irradiation technology appears to be a promising non-thermal pasteurization strategy for certain types of nuts.  相似文献   
960.
Kimchi was fermented in onggi and other containers at 4 °C for 4 weeks. Two types of onggi were used: glazed and nonglazed onggi. Other containers such as polyethylene plastic containers, polypropylene containers for use in a kimchi refrigerator, stainless steel and glass bottles were used. During the fermentation, kimchi fermented in onggi showed relatively stable acidity change compared with those in the other containers. Also it showed higher lactic acid bacteria multiplication (108–109 cfu g?1 at 4th week) but slower general aerobic bacteria multiplication than the others. The springiness of kimchi fermented in onggi was more than 50% at 4th week, it is higher than the others. Its carbonic acid taste and overall acceptability were excellent in sensory evaluations. The antioxidative and cancer‐cell antiproliferative activities were also greater in kimchi fermented in onggi than the others. Between the two types of onggi, nonglazed onggi showed better results in both properties and functionalities of kimchi. Onggi showed higher gas permeability than polyethylene plastic containers and glass bottles because of its porous structure, and lactic acid bacteria could have benefited from this condition. It possibly contributes to optimal ripening of kimchi resulting in better properties, especially texture and taste, and health functionalities.  相似文献   
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