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951.
白酒行业食品安全管理现状及趋势   总被引:3,自引:0,他引:3  
王明  沈才洪 《酿酒科技》2010,(1):114-116
从法规要求、市场需求、消费者期望等角度阐述了白酒行业食品安全管理的必要性和重要性。以泸州老窖为例,分析了从原粮种植、采购、基酒酿造、贮存、勾调、包装等环节可能产生的食品安全危害及控制要点,剖析了白酒行业食品安全管理现状。展望了白酒行业食品安全管理的发展趋势。  相似文献   
952.
食品交联酶对于食品的质构改善有着重要的影响,在烘焙制品等食品生产中发挥着巨大的作用。此文介绍了改变食品质构的几类直接交联酶的性质、交联机理以及在食品生产上的具体应用和展望。  相似文献   
953.
目的:探讨湖北掌叶覆盆子叶水提取物对高血糖模型小鼠和高血糖人群的降血糖作用。方法:采用四氧嘧啶诱导的高血糖模型小鼠模型,连续给予0.40、0.80、1.20g/kg bw的水提取物,观察其对空腹血糖和给葡萄糖后糖耐量以及血糖曲线下面积的影响,同时设置模型对照组。选择106例Ⅱ型糖尿病患者,采用随机盲法分成2组,实验组服用水提取物颗粒,对照组不给予任何干预措施,两组原服用降糖药物品种和剂量不变,连续服用30d后,检测空腹血糖和餐后2h血糖,以及血常规、肝、肾功能、大小便常规等安全性指标。结果:在高血糖模型小鼠实验中,水提取物0.80、1.20g/kg bw剂量组可显著降低空腹血糖,1.20g/kg bw剂量组可显著降低血糖曲线下面积,与模型对照组比较差异显著(P<0.05);在人群实验中,实验组临床症状改善总有效率明显高于对照组,实验组空腹血糖下降率为16.9%和餐后2h血糖下降率为16.0%,与试食前比较及对照组比较差异极显著(P<0.01)。结论:湖北掌叶覆盆子叶水提取物有明显的降血糖作用。  相似文献   
954.
发酵调味品中黄曲霉毒素检测控制技术概论   总被引:2,自引:0,他引:2  
黄曲霉毒素是发酵调味品中最大的安全隐患,研究其检测和控制技术是发酵调味品安全控制的重点。文章论述了发酵制品黄曲霉毒素检测控制的重要性及相关的技术,分析了发酵制品中黄曲霉毒素控制技术的发展前景。  相似文献   
955.
In this study Amplified Fragments Length Polymorphisms (AFLPs) analysis was applied on DNA extracted from different monovarietal olive oils. The aim was to study how the length of storage after milling of the oil can affect the use of DNA as an analyte for molecular traceability. Results, all assessed by statistical analyses, showed that the authentication of olive oil with molecular methods should be performed within a month from olive oil production. After this period, a significant decrease of quality of DNA extracted from olive oil was observed, with a consequent loss of information, that can affect the reliability of the results.  相似文献   
956.
ABSTRACT: The use of pulsed high hydrostatic pressure was investigated as a possible approach to stabilize foodstuffs. The objective of this article was to investigate the effect of the main processing variables (pressure [150 to 300 MPa], temperature levels [25 to 50 °C], and pulse number [1 to 10]) on the sanitation of nonpasteurized clear Annurca apple juice as well as freshly-squeezed clear orange juice. The aim of the article was the optimization of the process parameters in step-wise pressure treatment (pressure holding time of each pulse: 60 s, compression rate: 10.5 MPa/s, decompression time: 2 to 5s). The shelf life of the samples, processed at optimized conditions, was evaluated in terms of microbiological stability and quality retention. According to our experimental results, the efficiency of pulsed high pressure processes depends on the combination of pulse holding time and number of pulses. The pulsed high pressure cycles have no additive or synergetic effect on microbial count. The efficacy of the single pulses decreases with the increase of the pulse number and pressure level. Therefore the first pulse cycle is more effective than the following ones. By coupling moderate heating to high pressure, the lethality of the process increases but thermal degradation of the products can be detected. The optimization of the process condition thus results in a compromise between the reduction of the pressure value, due to the synergetic temperature action, and the achievement of quality of the final production. The juices processed under optimal processing conditions show a minimum shelf life of 21 d at a storage temperature of 4 °C.  相似文献   
957.
Quantitative analysis of food structure is commonly obtained by image analysis of a small portion of the material that may not be the representative of the whole sample. In order to quantify structural parameters (air cells) of 2 types of bread (bread and bagel) the concept of representative volume element (RVE) was employed. The RVE for bread, bagel, and gelatin-gel (used as control) was obtained from the relationship between sample size and the coefficient of variation, calculated from the apparent Young's modulus measured on 25 replicates. The RVE was obtained when the coefficient of variation for different sample sizes converged to a constant value. In the 2 types of bread tested, the tendency of the coefficient of variation was to decrease as the sample size increased, while in the homogeneous gelatin-gel, it remained always constant around 2.3% to 2.4%. The RVE resulted to be cubes with sides of 45 mm for bread, 20 mm for bagels, and 10 mm for gelatin-gel (smallest sample tested). The quantitative image analysis as well as visual observation demonstrated that bread presented the largest dispersion of air-cell sizes. Moreover, both the ratio of maximum air-cell area/image area and maximum air-cell height/image height were greater for bread (values of 0.05 and 0.30, respectively) than for bagels (0.03 and 0.20, respectively). Therefore, the size and the size variation of air cells present in the structure determined the size of the RVE. It was concluded that RVE is highly dependent on the heterogeneity of the structure of the types of baked products.  相似文献   
958.
Beef patties formulated to contain beef fat, plant oil, and a rosemary extract to increase unsaturated fatty acid content and maintain desirable sensory attributes were compared to control beef patties formulated without plant oils. Treatment patties were formulated to a fat content of 10% or 20% by combining beef trimmings (6% fat) with 4% or 14% addition of a lipid blend. Blends contained 57% beef tallow, 0.3% rosemary extract, and 43% of high oleic safflower oil (SO), olive oil (OO), or corn oil (CO). Lipid oxidation, as measured by TBA values, of treatment patties were similar to control patties after 0 and 3 d of refrigerated (2 °C) storage and up to 56 d of frozen (-10 °C) storage. Cooked lipid blend patties having a fat content of 10% or 20% were similar to or higher than control patties for juiciness and were no different for other sensory attributes evaluated. At fat levels of 10% or 20%, oleic acid (18: 1) in cooked SO patties (46.1% and 50.3%, respectively) and OO patties (43.8% and 48.1%, respectively) was higher than the control (37.3% and 37.6%, respectively). Unsaturated to saturated fatty acid ratios at the 10% or 20% fat levels were higher in SO (1.37 and 1.60, respectively) and CO (1.40 and 1.48, respectively) patties than the control (0.97 and 0.94, respectively). Beef patties manufactured with varying lipid blends increased unsaturated fatty acid content and were similar in physical characteristics and sensory attributes of all beef patties formulated without lipid blends. PRACTICAL APPLICATION: The development of healthier beef products that will be more appealing to consumers has long been an industry goal. The authors believe that lipid blends such as the one used in this study could be used to create such products, not only in the form of beef patties, but any number of processed meat products. Because the materials and equipment used to create the lipid blends in this study are widely available, their incorporation into meat products would represent a small capital investment. This is an important factor in bringing a reasonably priced, healthier product to consumers.  相似文献   
959.
Review: Nanocomposites in Food Packaging   总被引:2,自引:0,他引:2  
ABSTRACT:  The development of nanocomposites is a new strategy to improve physical properties of polymers, including mechanical strength, thermal stability, and gas barrier properties. The most promising nanoscale size fillers are montmorillonite and kaolinite clays. Graphite nanoplates are currently under study. In food packaging, a major emphasis is on the development of high barrier properties against the migration of oxygen, carbon dioxide, flavor compounds, and water vapor. Decreasing water vapor permeability is a critical issue in the development of biopolymers as sustainable packaging materials. The nanoscale plate morphology of clays and other fillers promotes the development of gas barrier properties. Several examples are cited. Challenges remain in increasing the compatibility between clays and polymers and reaching complete dispersion of nanoplates. Nanocomposites may advance the utilization of biopolymers in food packaging.  相似文献   
960.
Abstract: To assess the ability of lactic acid bacteria to improve some nutritional characteristics of the pearl millet–soybean slurry to prepare complementary foods for young children in African countries, inoculation was performed using strains previously selected for their ability to hydrolyse starch, phytate, or α-galactooligosaccharides (α-GOS). For the sake of comparison with the action of a natural microflora, fermentation was also performed by back slopping inoculation, that is, with a sample obtained from spontaneously fermented traditional pearl millet slurry obtained from a small scale processing unit in Burkina Faso (Ouagadougou). Starter cultures thrived on the slurry as shown by counts on MRS agar, TTGE fingerprints, and fermentation patterns. The fermentation of precooked slurries inoculated by back slopping or with mixed cultures containing the amylolytic strain Lb. plantarum A6 enabled partial starch hydrolysis. Corresponding gruels had a suitable consistency for young child feeding at high dry matter content, and a high energy density: 88.7 ± 4.2 and 75.8 ± 5.1 kcal/100 g of sweetened gruel, for the gruels inoculated by back slopping or with Lb. plantarum A6, respectively. Unexpectedly, no decrease in phytates was observed in any of the experiments, suggesting the presence of one or more inhibitory compounds in soybean. Furthermore, preprocessing conditions before fermentation affect the carbohydrate composition of slurry and have a more profound effect than fermentation on the reduction of the α-GOS content. Practical Application: This research aims to investigate the capacity of selected lactic acid bacteria to produce in a bioprocess high energy density and nutritious gruels for complementary feeding of young children from an African cereal (pearl millet) mixed with soybean.  相似文献   
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