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In order to investigate the relationship between profile of myofibrillar proteins and tenderness among 2 kinds of Chinese hams (Jinhua and Xuanwei) and 3 kinds of European hams (Iberian, Serrano and Parma), shear force, myofibril fragmentation index (MFI), SDS-PAGE, carbonyls content and Raman spectroscopy were investigated. The shear force and salt content of Chinese hams were significantly higher than that of European hams, while moisture content was lower than that of European hams (p < 0.05). MFI values and SDS-PAGE profile revealed that the degradation of myofibrillar proteins in Chinese hams was lower than in European hams. In addition, Chinese hams showed significantly higher carbonyls content and β-sheet content compared with European hams, indicated that proteins aggregation intensively inhibited the degradation of myofibrillar proteins in Chinese hams. These results indicated that the higher shear force in Chinese style hams could be attributed to the lower moisture content and limited proteolysis.  相似文献   
3.
为了生产优良食味稻米,克服栽培环境的影响非常重要。主要论述了灌浆期最适宜的用水管理、新鲜稻谷的干燥温度以及糙米水分含量与其食味之间的关系。水稻灌浆期最适宜的用水管理是湿润管理法,通过对灌浆期水稻的湿润管理,可有效抑制水田土壤温度上升,保持根系活力,提高稻米结实率,最终实现稻米增收与食味提升。新鲜稻谷水分含量不同,干燥所需的送风温度也不同,22%、25%、30%的水分含量分别对应的适宜温度为55、48、35℃。糙米中14%~15%的水分含量能够保证稻米的最佳食味。  相似文献   
4.
High moisture mozzarella from cow milk is a pasta filata cheese that can be manufactured by different protocols. Fermentation by autochthonous starter is used for the traditional product, whereas direct acidification with citric acid is widely used at industrial level. Both types are stored immersed in a liquid for preserving freshness, but this packaging method is known to favour the changes of the quality characteristics. The present study aimed to assess the evolution of the soluble compounds and to evaluate their use as chemical indices for discriminating the two types of mozzarella. The contents of lactose, organic acids, water-soluble nitrogen and free amino acids differently changed over time. The whole patterns of these soluble compounds allowed discrimination of the two products during the whole storage period. The simple analyses of lactic acid and lactose could be a rapid tool to protect traditional mozzarella from industrial imitations obtained with citric acid.  相似文献   
5.
Resistant starch (RS) can be generated through heat moisture treatment (HMT). The HMT was conducted by modifying starch using different ratio of moisture content, high temperature and heating time. A number of studies showed that the effects of HMT on RS contents in cereals, pulses, tubers and fruits were inconsistent. This study aimed to analyse the impact of HMT on RS level in various carbohydrate sources through a meta-analysis approach. Study selection was conducted with the PRISMA method. There were 21 relevant studies and 67 data used for meta-analysis. The database was analysed by using Hedges’ d. The results showed that there was a significant impact of HMT on RS level of cereals, especially wheat. The highest increase in RS levels for various carbohydrate sources in starch was influenced by the interaction of treatment between water content at 15 ≤ x < 25%, heating time at 0.25 < x ≤ 6 h and temperature at 120 ≤ x ≤ 130 °C.  相似文献   
6.
Developing wound dressings that have strong adhesion strength without causing any conglutination to the wound site is still challenging. Herein, is proposed that zwitterionic shape memory polymers can be applied as promising candidates for wound dressing. Sulfobetaine methacrylate (SBMA) is copolymerized with 2,3‐dihydroxypropyl methacrylate (DHMA) in the presence of boric acid as a cross‐linking agent. The prepared material exhibits multi‐stimuli responsive shape memory behaviors: it can rapidly return to its initial shape upon heating to 90 °C, and a gradual recovery is also observed by absorbing moisture in humid environments. The shape memory effect can be well adjusted via incorporation of sodium chloride to induce the dissociation of electrostatic interactions between PSBMA chains, leading to reduced transition temperature and faster shape recovery rate. Moreover, the dynamic nature of boron ester bonds and electrostatic interaction endows the material with effective and rapid self‐healing ability. It is also demonstrated that the deployment process of the dressing that a sample with an initially circular shape can perfectly fit and tightly bind to the wound site after moisture‐induced shape recovery. The proposed zwitterionic polymer can possibly extend the application scope of shape memory polymers and pave a new way for the design of wound dressings.  相似文献   
7.
为了根据某瓦楞纸箱生产厂的实际生产条件制备一种耐热、耐低温、防水、透气等性能优异的包装专用蜡,将58号全炼蜡和70号微晶蜡混合物作为基础蜡料,分别考察添加剂、助剂、抗氧剂等对基础蜡料滴熔点、运动黏度及外观等的影响,确定了最佳制备配方:合成蜡、添加剂B、助剂1、助剂2、抗氧剂加入量(w)分别为基础蜡料质量的9.8%,6.5%,1.5%,2.1%,0.1%。在温度为160 ℃、时间为30 min、搅拌速率为200 r/min条件下制备的包装专用蜡具有熔点高、黏附性强、光泽性好的优点,满足该瓦楞纸箱生产厂的质量和外观要求。  相似文献   
8.
通过在6198采煤工作面现场施工煤层注水钻孔采取煤样,实验室试验注水钻孔水压力分布、煤样含水率变化,得到了工作面煤层注水影响半径等技术参数,为采煤工作面煤层注水提供了一定的参考依据。  相似文献   
9.
Abstract

The knowledge of moisture content (MC) and drying stress are crucial parameters to control the drying process and maintain the quality of dried wood. Herein, we investigated the pattern of moisture transfer and stress development in Chinese fir during the high-temperature drying process. The MC in each layer of lumber was separated into bound water and free water via nuclear magnetic resonance (NMR), and the drying and residual stress were measured using prong test method. There was different MC in each layer along the thickness, resulting in an MC gradient that initially increased and then decreased, which is consistent with the trend of drying stress. The T21 peak indicating bound water shifted to the left especially when MC was below the fiber saturation point, signifying that the discharge of moisture became difficult with prolonged drying time. The ratio of bound water to free water was different in each layer, indicating that the moisture transfer was different along the thickness. Furthermore, the residual stress was greater than the corresponding drying stress though the disparity reduced gradually, which suggests that the MC gradient was the largest affecting factor for drying stress at high MC stages but decreased to some extent as the drying process continued.  相似文献   
10.
为研究高盐高有机制药废水污泥的电渗透脱水效果,深入认识化学污泥的电脱水过程,本文采用电渗透高干脱水技术对经抽滤脱水的高盐高有机制药废水化学污泥进行深度脱水,考察了泥饼初始pH的改变对污泥电渗透高干脱水过程中阴阳极污泥的含水率、电流、电导率、pH、zeta电位与能耗的影响,验证了对高盐高有机制药废水污泥实行电渗透高干脱水的可行性,解析了化学污泥电渗透脱水过程的机制。结果表明,泥饼pH为2、3、4时,zeta电位为正值,电渗流反向流动,无法脱水;pH增至5时,zeta电位为负值,电渗流从阴极脱除,污泥含水率从53.2%降至44.8%,脱水效果最好;但pH增至6时,脱水量有所降低。污泥电导率随pH的增加而降低。pH为5时初始电流最大。脱水15min时,即污泥含水率降至45.5%时,能源利用率最高。  相似文献   
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