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1.
为改善传统发酵鹿肉干品质和风味的缺陷,向复配发酵剂(无戊糖片球菌:木糖葡萄球菌:植物乳杆菌=2:2:1)发酵的鹿肉干加入一定量的鸡脂肪,比较不发酵不加脂、发酵不加脂和发酵加脂三组鹿肉干的营养特性和风味的差异。结果表明:通过感官综合分析鸡脂肪最佳添加量为2%;发酵加脂组和不发酵不加脂组L*值分别为20.13和19.67,无显著性差异(P > 0.05),但a*值(7.73)和b*值(9.29)值都显著高于不发酵不加脂组a*值(1.58)和b*值(2.34)(P<0.05);发酵加脂组的水分含量(15.22%)和不发酵不加脂组(21.33%)显著高于发酵不加脂组(14.1%)(P<0.05);发酵加脂组pH(5.04)显著(P<0.05)低于不发酵不加脂组pH(5.89)和发酵不加脂组pH(5.28);发酵加脂组硬度(5071.22%)显著(P<0.05)低于不发酵不加脂组硬度(21143.94%)和发酵不加脂组硬度(10324.73%);发酵加脂组脂肪酸(7.229 mg/100 g)比不发酵不加脂组脂肪酸(2.635 mg/100 g)和发酵不加脂组脂肪酸(3.591 mg/100 g)显著增加(P<0.05);发酵加脂组氨基酸(12.218%)比不发酵不加脂组氨基酸(8.43%)和发酵不加脂组氨基酸(10.213%)显著增加(P<0.05);发酵不加脂组和发酵加脂组挥发性物质中烯烃类相对含量分别为66.06%和55.85%,差异显著(P<0.05),醛类、酸类、烷烃类含量显著相比,增加(P<0.05),而醇类和杂环化合物含量显著减少(P<0.05);综上,发酵及定量的鸡脂肪的添加对发酵鹿肉干的品质有积极影响,更加突出了发酵鹿肉干的营养特性和风味。  相似文献   
2.
氧化石墨烯负载纳米Fe3O4类芬顿处理制药废水   总被引:1,自引:0,他引:1  
采用改进Hummer法制备了氧化石墨烯(GO)负载纳米Fe3O4磁性催化剂(Fe3O4/GO),对其进行了X射线衍射仪、扫描电子显微镜和能量-色散光谱表征,并将其应用于多相类芬顿处理高浓化学原料药生产废水。结果表明,Fe3O4颗粒成功负载在GO表面,且没有出现明显的团聚现象。当废水的pH为3,双氧水(H2O2的质量分数30%)投加量10 mL/L,催化剂投加量2 g/L,反应120 min后COD去除率达78%,UV254去除率高达81%。三维荧光光(3D-EEM)分析可知,芳香类和富里酸类物质在催化降解过程中得到有效去除。  相似文献   
3.
为了解壳聚糖-荔枝木质精油可食膜在食品保鲜中的应用,在壳聚糖溶液中添加0%、2%、4%、6%、8%和10%的的荔枝木质精油(v/v,以壳聚糖溶液体积为基准),配制壳聚糖-荔枝木质精油可食膜,通过比较复合可食膜的机械性能、阻隔性能、抑菌性及抗氧化能力,获得最佳荔枝木质精油添加量;并以该比例精油复合可食膜进行冷鲜鸡肉包裹保鲜实验,对比普通保鲜膜包裹保鲜,分析冷鲜鸡肉的感官指标及品质变化(pH、挥发性盐基氮(TVB-N)及菌落总数)。研究发现:随着精油添加比例的增加,复合可食膜的机械性能、阻隔性能、抑菌性能及抗氧化性能均有所提升,其中添加体积比8%的壳聚糖-荔枝木质精油可食膜各性能最佳,其膜厚度为0.044±0.0012 mm,水蒸气透过率(water vapor permeability,WVP)为0.499±0.019 g·mm/m2·h·KPa,膜拉伸强度为34.674±1.2 MPa,延伸性为53.92%±1.04%,DPPH清除率为32.51%±1.42%,ABTS清除率为35.74%±1.14%;以该比例进行冷鲜鸡肉保鲜实验,在7 d的保鲜期间,TVB-N及菌落总数变化得到有效抑制。结果表明:添加荔枝木质精油的壳聚糖复合可食膜包裹保鲜鸡肉与普通保鲜膜包裹相比,可有效延长冷鲜鸡肉的货架期,具有更好的保鲜效果。  相似文献   
4.
The sustainable reduction of greenhouse gas emissions from road transport requires solutions to achieve net-zero carbon dioxide emissions. Therefore, in addition to vehicles with electrified powertrains, such as those implemented in battery electric of fuel cell vehicles, internal combustion engines fueled with e-fuels or biofuels are also under discussion. An e-fuel that has come into focus recently, is hydrogen due to its potential to achieve zero tank-to-wheel and well-to-wheel carbon dioxide emissions when the electrolysis is powered by electricity from renewable sources. Due to the high laminar burning velocity, hydrogen has the potential for engine operation with high cylinder charge dilution by e.g. external exhaust gas recirculation or enleanment, resulting in increased efficiency. On the other hand, the high burning velocity and high adiabatic flame temperatures pose a challenge for engine cooling due to increased heat losses compared to conventional fuels. To further evaluate the use of hydrogen for small passenger car engines, a series production 1 L 3 cylinder gasoline engine provided by Ford Werke GmbH was modified for hydrogen direct injection. The engine was equipped with a high pressure external exhaust gas recirculation system to investigate charge dilution at stoichiometric operation. Due to limitations of the turbocharging system, very lean operation, which can achieve nitrogen oxides raw emissions below 10 ppm, was limited to part load operation below BMEP = 8 bar. Thus, a reduction of the nitrogen oxides emission level at high loads compared to stoichiometric operation was not possible. At stoichiometric operation with external exhaust gas recirculation engine efficiency can be increased significantly. The comparison of stoichiometric hydrogen and gasoline operation shows a reduced indicated efficiency with hydrogen with significant faster combustion of hydrogen at comparable centers of combustion. However, higher boost pressures would allow to achieve even higher indicated efficiencies by charge dilution compared to gasoline engine operation.  相似文献   
5.
The gel-forming ability of myofibrillar protein (MP) is highly correlated with the characteristics of emulsified meat products. Incorporation of Agaricus bisporus (Ab) powder into MP gels may enhance its gel properties to facilitate the development of a novel and safe meat product. Therefore, this study investigated the effects of Ab powder on gel strength, water holding capacity (WHC), texture, rheological behaviour, LF-NMR spin–spin relaxation (T2), microstructure and protein secondary structure of the MP gel system. The results indicated that the gel strength, WHC, G' value and G" value were significantly improved when the addition of Ab powder increased from 0% to 6% (P < 0.05). Meanwhile, the T2 relaxation time was shortened, and free water was transformed into immobilised water. The texture of the gel was improved when 1%–4% Ab powder was added compared to the control. Furthermore, Ab filled in the gel network and promoted the unfolding of MP α-helix and the formation of MP β-sheet during the thermal denaturation of MP, leading to a dense aggregated network structure. The study suggested that Ab could be a promising ingredient in improving chicken MP's gel properties and developing fat-reduced meat products.  相似文献   
6.
《Journal of dairy science》2022,105(4):3176-3191
Milk concentrates are used in the manufacturing of dairy products such as yogurt and cheese or are processed into milk powder. Processes for the nonthermal separation of water and valuable milk ingredients are becoming increasingly widespread at farm level. The technical barriers to using farm-manufactured milk concentrate in dairies are minimal, hence the suspicion that the practice of on-farm raw milk concentration is still fairly uncommon for economic reasons. This study, therefore, set out to investigate farmers' potential willingness to adopt a raw milk concentration plant. The empirical analysis was based on discrete choice experiments with 75 German dairy farmers to identify preferences and the possible adoption of on-farm raw milk concentration. The results showed that, in particular, farmers who deemed the current milk price to be insufficient viewed on-farm concentration using membrane technology as an option for diversifying their milk sales. We found no indication that adoption would be impeded by a lack of trustworthy information on milk processing technologies or capital.  相似文献   
7.
Frozen poultry meat is the most widely consumed animal-based food. However, water loss often leads to quality loss of poultry meat. Therefore, the present study sought to investigate the combined effect of calcium chloride (CaCl2) and pulsed electric fields (PEF) treatment on chicken breast meats and the mechanisms underlying protein degradation. The results showed that the synergistic effect was superior to the single treatment. Compared with the untreated group, the combination of CaCl2 and PEF increased water holding capacity of chicken breast meats by 16.61% and decreased cooking loss by 28.93%. Low-field nuclear magnetic resonance (LF-NMR) results indicated that the synergistic treatment promoted water molecules' binding capacity in myofibrils of poultry meat, which exhibited higher immobilised water. Additionally, the combination of CaCl2 and PEF led to increased degradation of proteins of high-molecular weight and surface hydrophobicity of myofibrillar protein. Furthermore, the extension of the protein molecule and microenvironmental changes promoted interaction between protein and water. In conclusion, the synergistic treatment of CaCl2 and PEF enhanced water retention and improved physicochemical properties of the myofibrillar protein in chicken breast meats.  相似文献   
8.
为了使白切鸡卤水标准化,推进其高值化利用,本文以黄油鸡和土二鸡为制作白切鸡的原料,研究了两种原料鸡在不同蒸煮次数(2、4、6、8次)下产生的卤水中营养成分的变化。此外,采用顶空固相微萃取-气相色谱-质谱联用法,测定了两种原料鸡在不同蒸煮次数卤水中的风味物质。结果表明:随着蒸煮次数的增加,白切鸡卤水中的蛋白质、脂肪、碳水化合物等营养成分均显著增加(P<0.05)。在蒸煮第2、4、6、8次的卤水中检测出醛类、醇类、酮类三类主要挥发性风味物质,其中黄油鸡卤水挥发性物质有52种,土二鸡有41种;醛类物质是鸡汤的主要物质,黄油鸡有31种,土二鸡有24种。综合分析,土二鸡卤水比黄油鸡卤水的利用价值高,与理化测定和风味测定结果相吻合。本文的研究结果可为白切鸡加工原料的选择提供一定的参考,同时,对白切鸡卤水的标准化生产提供数据支撑。  相似文献   
9.
采用流变扫描、凝胶强度、核磁共振、扫描电子显微镜等,探究明胶对鸡肉糜3D打印成型稳定性的影响。结果表明,不同明胶添加量(0%、2%、4%、6%、8%,以肉质量计)的鸡肉糜均表现出剪切稀化行为,具备3D打印可行性。明胶增强了体系的黏度和凝胶强度,提高了鸡肉糜3D打印成型稳定性,但过高的明胶添加量会影响物料的挤出,降低打印样品的形状精度。当明胶添加量为4%时,样品表现出良好的精度和成型稳定性,此时打印后形状塌陷率为2.46%。对添加4%明胶的3D打印样品进行蒸煮品质评价,发现3D打印会使样品的蒸煮损失增大,但质构特性得到适当改善。  相似文献   
10.
为有效控制供水管网中的三卤甲烷浓度,考察了以太湖和阳澄湖为双水源的管网水中三卤甲烷的变化趋势。采集S市分别经过A水厂(以太湖为水源)和B水厂(以阳澄湖为水源)处理后的供水管网水样,探讨三卤甲烷和余氯浓度随供水距离的变化规律,并进行了三卤甲烷-余氯和三卤甲烷-供水距离的线性回归分析。结果表明,在A、B水厂单独供水管网中,三卤甲烷随供水距离的增加而升高,余氯浓度随供水距离的增加而降低;在A、B水厂同时供水的对置供水管网中,三卤甲烷浓度由A水厂到B水厂呈现先升高后降低的变化规律,而余氯浓度则呈现先降低后增加的变化规律,对置供水管网中10 km处为水力交接点,此处余氯浓度最低,三卤甲烷浓度最高。经线性回归分析发现,三卤甲烷浓度与余氯浓度和供水距离之间存在显著的相关性,并且温度对模型的影响较大。  相似文献   
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