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991.
The developmental changes of carbohydrates, organic acids, amino acids and phenolic compounds in ‘Honeycrisp’ apple flesh were investigated using GC–MS and HPLC. A total of 12 carbohydrates, 8 organic acids, 20 amino acids, and 18 phenolic compounds were identified and quantified. Each metabolite showed characteristic changes during fruit development, but in general, concentrations of most sugars and sugar alcohols either increased or remained unchanged whereas concentrations of most organic acids, amino acids and phenolic compounds decreased with fruit development, indicating that most sugars and sugar alcohols are synthesised and/or accumulate at a faster or similar rate relative to fruit growth whereas organic acids, amino acids and phenolics are synthesised and/or accumulate at a slower rate relative to fruit growth. On a whole fruit basis, the content of most metabolites increased with fruit development. In the flesh of mature ‘Honeycrisp’ apple, fructose and sucrose and sorbitol are the major sugars and sugar alcohol; malic acid is the major organic acid; aspartic acid, asparagine, glutamic acid, proline, threonine and γ-aminobutyric acid are the major amino acids; and procyanidin B1, procyanidin B2, chlorogenic acid, catechin and epicatechin are the major phenolic compounds, respectively.  相似文献   
992.
菊花绿茶复合饮料的研制   总被引:1,自引:0,他引:1  
以绿茶、菊花为主要原料,研究了菊花茶饮料加工工艺中的最佳浸提方法和条件,确定了饮料的最佳调配比例。结果表明,采用微波辅助水浴法浸提得到的浸提液品质较常规水浴法的好,微波辅助水浴法浸提绿茶的最佳工艺条件为:茶水比1∶100、pH5、微波功率为400W条件下处理4min、90℃水浴锅中浸提10min;菊花浸提最佳工艺条件为:料水比1∶180、微波功率为175W条件下处理10min、80℃水浴锅中浸提15min。饮料最佳调配比例为绿茶汁40%、菊花汁50%、白砂糖2%、柠檬酸0.02%。  相似文献   
993.
12.5%保得悬浮剂防治地下害虫试验   总被引:1,自引:0,他引:1  
胡兆农  姬志勤  吴文君  田小卫 《农药》2000,39(11):29-31
1998年7月~1999年6月,我们进行12.5%的保得悬浮剂室内盆载及在玉米和小麦田防治地下害虫药效试验,试验结果表明,12.5%保得悬浮剂对地下害虫有很好的防效,拌种各处理的保苗效果与40%甲基柳磷乳油的防效基本相当。  相似文献   
994.
为了适应大规模的机械化生成,以平面图来表达三维实体为设计思想,二维工程图在指导生产、装配和技术交流等方面起到了举足轻重的作用.目前,随着计算机技术的飞速发展,现代设计越来越注重三维实体造型的应用,因为通过三维造型可以分析产品的动态特性、直观地表达设计效果和构造动画模型等[1].  相似文献   
995.
    
In this study, the potential of a novel method based on an artificial neural network was investigated to analyze the color change of raw chicken breasts during refrigeration. As edible meat for people, chicken breasts have high nutrients and low-fat content. Therefore, people consume it as a safe and high-value food in their daily diet. The investigation of chicken breast freshness is proposed as a significant issue in the meat industry because raw meat spills rapidly. The color change of raw chicken breasts over time reflects subtle biochemical changes, as well as changes in freshness. However, owing to the impact of the photographic equipment and illumination, a significant color discrepancy exists between the captured image and the intrinsic color. It is difficult to separate chicken breast color changes from color discrepancies when comparing images captured at different timestamps. Thus, we propose a color change analysis method for raw chicken breast that uses color correction to suppress the influence of color discrepancy and uses CNN to extract discriminant features for timestamp classification analysis. The experimental results indicate that the proposed method improves all three CNN models by achieving higher accuracy, and the best model was improved from 80.05%$$ 80.05% $$ to 95.66%$$ 95.66% $$, demonstrating the effectiveness of the proposed method. © 2024 Institute of Electrical Engineer of Japan and Wiley Periodicals LLC.  相似文献   
996.
    
The objective of the study was to investigate the impact of germinated brown rice flour (GBRF) on the mechanism of high gluten wheat flour (HGWF) network formation and dough properties. Therefore, dough properties, microstructures, stability mechanism and bread quality were evaluated. Results showed that HGWF+10%GBRF exhibited a higher dough stability time (DST), pasting temperature, storage modulus (G′) and loss modulus (G′′), as well as a lower compliance value. The microstructure of dough showed that GBRF interfered with the self-organization of gluten protein molecules and affected the formation of gluten network structure. The disulfide bonds and β-sheet structure were proved to play an important role in facilitating the formation of a stable three-dimensional network structure, which revealed the regulatory mechanism of GBRF in maintaining the dough stability and strength. Furthermore, the dough mixing properties and texture parameters (i.e., hardness and fracturability) of breads were significantly correlated. Overall, GBRF can be used as a potential ingredient for whole grain products and its realistic role in bread-making has been demonstrated.  相似文献   
997.
    
Whole grains and legumes are important sources of nutrients and have essential influences in the human diet. However, the consumption of whole grains and legumes faces many challenges, such as their poor edible and cooking qualities. Antinutritional factors and allergens also affect consumption of whole grains and legumes. High hydrostatic pressure (HHP) treatment is a recent non-thermal processing technology, which can improve the edible quality of whole grains and legumes. HHP also preserves the natural nutrition and freshness of food by lowering the concentration of antinutritional elements and sensitizing allergens while minimally altering the color and scent of the food components. This review summarized the principle of HHP treatment technology, the effects of HHP treatment on the nutritional components, antinutritional factors, and cooking qualities of whole grains and legumes. This review also described the potential effects of HHP-treated whole grains and legumes on some diseases. This review is expected to provide references for the application of HHP treatment in whole grains and legumes.  相似文献   
998.
    
To improve the heat resistance of lactobacilli during spray-drying, we first investigated the effect of heat shock and repair treatment on the heat resistance of Lactiplantibacillus plantarum LIP-1, and the specific cell repair mechanism. Compared with control group, the reduction of the strain after the heat treatment (75 °C for 40 s) decreased from 1.05 to 0.36 log CFU/mL (initial cell counts 9.30 log CFU/mL) by heat shock (44 °C for 10 min). The residuals of the strain after heat-treated increased by 0.90 log CFU/mL by heat shock firstly, and then the repair treatment (30 °C for 10 min).During recovery period, the relative content of unsaturated long-chain fatty acids (C18:1n9 & C18:2n6) induced by heat shock proteins increased by 7.0%, and the amount of DnaK protein anchored on the cell membrane increased by 0.17 pg/mL. Cell membrane damage caused by heat shock was reduced and strain heat resistance was improved.Industrial relevanceOur research found that the repair treatment after heat shock reduced cell membrane damage caused by heat shock, which is a very promising technology for improving the heat resistance of L. plantarum LIP-1. This technology is also expected to be widely used in the preparation of LAB powders by spray-drying technology.  相似文献   
999.
    
Lactic acid bacteria are important fermentation strains, and improving their freeze-drying survival rate (FDSR) has become a hot research topic in recent years. In this research, we found that adding 0.1 g/L L-glutamate to culture medium improved the FDSR of four strains of L. plantarum. Using L. plantarum LIP-1 as an example, we explored the internal mechanism of this phenomenon. L-glutamate had this effect through two metabolic pathways. First, it made the strain grow rapidly and produce more acid, resulting in a rapid decline of pH in the culture environment. The acidic environment led to the upregulation of the dnaK gene and secG gene expression, increased DnaK protein levels, promoted its anchoring effect on the cell membrane, and enhanced the integrity of the cell membrane. Second, it upregulated the expression of the murL, murD, and vanY genes, increased peptidoglycan synthesis, and increased cell wall integrity. In sum, the strain obtained a higher FDSR by adjusting the cell membrane and cell wall structure using L-glutamate. This study provides a new method for improving the FDSR of lactic acid bacteria.  相似文献   
1000.
    
This paper examines the effects of annealing treatment (ANN) and heat-moisture treatment (HMT) on the physicochemical and structural properties of wheat starch used for 3D food printing. Printing performance, molecular weight (Mw), amylopectin branch chain length distribution, pasting properties, rheology, fourier transform infrared (FT-IR) spectroscopy, texture and scanning electron microscopy (SEM) were used to evaluate the quality of printed products. Compared to untreated wheat starch, HMT improved the accuracy of 3D printing, stacking height of printed samples, and prolonged storage time of printed sample with softer texture. Conversely, ANN decreased printing performance, made sample edges rougher, reduced the stacking height of printed samples, and significantly increased sample hardness in storage. These effects are consistent with changes that these treatments made to the Mw of starch: compared to native starch and ANN, HMT increased the Mw of amylose and significantly decreased average Mw. In turn, this change decreased viscosity and G' of the starch gel, enabling smoother extrusion and better printing lines. In conclusion, HMT can improve 3D printing performance of wheat starch, increasing printing height and accuracy, which provides a simple and effective method to improve 3D printing effect using starch.  相似文献   
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