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81.
3D online multi-user virtual environments (MUVEs) have a lot of potential in supporting older people in their daily lives, yet little research has been conducted to explore how older people engage with this type of technology. This paper aims to investigate the characteristics, user groups and activity patterns (particularly social networks and gift giving behaviour) of older users within a 3D online multi-user virtual environment. Data from approximately 5000 online user profiles of older and younger users from a 3D MUVE, namely IMVU, was collected for analysis. Overall, we identified several distinct patterns of use (e.g. size of social ties, level of reciprocity, etc.) among older users when compared with younger users. We also found that despite the capabilities of 3D MUVEs to provide the users immersion in alternative realities, a feature well embraced by younger users in this study, older users seemed more interested in activities which serve as an extension to their physical life.  相似文献   
82.

Modern healthcare's need for knowledge sharing and bridging the research–practice gap requires new forms of collaboration, in which clinicians of varying clinical and research expertise work together over geographical and organisational borders. To support such distributed communities of practice (CoPs), an understanding of their collaboration processes, outcomes, challenges and enablers is needed. The article examines these issues through a case study of a long-running CoP, the Swedish Oral Medicine Network (SOMNet). SOMNet's main form of collaboration is monthly telephone conference meetings centred on case consultations. Cases are submitted by the clinicians via a Web-based system. The methods used were interviews, observations, and a questionnaire. The work adds to previous research by studying a distributed CoP explicitly focused on supporting the transfer of scientific results from researchers to practitioners. We found that the regular meetings give a rhythm to the community. The centrality of cases means an immediate benefit for the submitter while the community is provided an authentic context for learning. SOMNet yields opportunities for help and learning for diverse expertise levels; the type of benefits is affected by the participant's degree of oral medicine knowledge and collaboration involvement. There are challenges in accommodating varying levels of expertise and encouraging those less experienced to participate. Enablers of the collaboration include the participation of experts, meeting facilitators and well-adapted ITs.  相似文献   
83.
以酒精糟、白酒糟、碎玉米、啤酒糟等为原料,添加尿素、(NH4)2SO4及营养液F,采用“液体种子培养,多菌种混合固态发酵技术”生产奶牛生物(活菌)饲料。饲料粗蛋白平均含量36.55%、提高率1635%;酵母菌、有效细菌总数及活菌率分别为:7.85×10^8个g、7.11×10^9个,g和82.2%;β-淀粉酶1356mg/(g.h)、纤维素酶168um/(g.h)、中性蛋白酶1088ug/(g.min)、碱性蛋白酶372ug/(g·min)、糖化酶110u/(g.h);VA80IU/(100g)、VB:2.35mg/(100g)、VD2945IU/(100g)、VC1.1mg/(100g)、烟酸10.7mg/(100g)。  相似文献   
84.
目的研究在不同的硝酸盐质量浓度下,MFC的产电、阴极反硝化情况及阳极COD和氨氮的处理情况.实现产电与阴极反硝化的同时进行.方法阳极以实验生活污水为处理对象,阴极以自配具有一定质量浓度的硝酸盐溶液为处理对象,改变阴极的硝酸盐质量浓度,阳极为间歇厌氧运行模式,阴极为间歇缺氧运行模式.结果 当硝酸盐质量浓度由20-200mg/L逐渐增加时,随着初始硝酸盐质量浓度的增加,亚硝酸盐的积累逐渐增加,最高可达65mg/L,硝酸盐相对去除率几乎没有变化,而硝酸盐的绝对去除率则逐渐减小.硝酸盐质量浓度从20~120mg/L变化时对微生物燃料电池的产电效果基本没有影响,当硝酸盐质量浓度增加到160mg/L时,平均输出电压和最高功率密度明显增加,而当硝酸盐质量浓度增加到200mg/L时,平均输出电压和最高功率密度又明显减少.结论阴极硝酸盐质量浓度为160mg/L时,MFC阳极COD的去除率最高,产电效果最好.  相似文献   
85.
This paper compared the degradation efficiency of sludge organic matters and electric-production by two typical microbial fuel cells——dual-chamber microbial fuel cell(DMFC)and single chamber air cathode microbial fuel cell(SAMFC),and the variations of sludge protein,polysaccharide and ammonia nitrogen within the systems were also investigated.The results showed that the concentration of sludge soluble chemical oxygen demand,protein and carbohydrate of DMFC are higher than these of SAMFC during the systems operation,while DMFC can achieve a better ammonia nitrogen removal than SAMFC.Under the same operation condition,the stable voltage output of DMFC and SAMFC is 0.61 V and 0.37 V;the maximum power density of DMFC and SAMFC is 2.79 W/m3and 1.25 W/m3;TCOD removal efficiency of DMFC and SAMFC is 34.14%and 28.63%for 12 d,respectively.Meanwhile,DMFC has a higher coulomb efficiency than SAMFC,but both are less than5%.The results showed that DMFC present a better performance on sludge degradation and electric-production.  相似文献   
86.
微生态制剂在水产养殖中的应用   总被引:1,自引:0,他引:1  
主要从防治鱼病的发生及减少抗生素滥用、改良水质和防治有害蓝藻等三个方面的作用综述了微生物制剂在水产养殖中的应用现状及研究进展,分析了目前微生物制剂研究及生产中存在的问题,并对微生物制剂在水产养殖中的研究及应用发展趋势作了进一步的展望。  相似文献   
87.
以张家港市作为“国家第一批卫生城市”、“双拥模范城市”、“中国优秀旅游城市”、“国际花园城市”、“全国文明城市”等多项荣誉为出发点,以党的十七大精神为指导,以精神文明建设为抓手,以创建和谐社区、统筹城乡发展目标为背景,通过杨舍镇乘航办事处这个区域为切入点,分析了影响农村社区居民文化生活品质的原因,提出了提升乘航片区居民文化生活品质的对策,为构建和谐新港城做出贡献  相似文献   
88.
当前,我国正处于城市化加速时期,城乡统筹下新农村的发展与建设是我国城市化进程中必须面对的重要现实任务,新农村社区公共空间的建设是我国当前及未来新农村建设的重要内容。在农村社会的构造中,存在着多元公共空间。随着农村社会结构的变动,多元的公共空间不断萎缩和消亡。在各地新农村社区建设工作如火如荼进行的同时,怎样规划设计新农村社区公共空间,提高村民的生活环境质量,改善生活品质,促进新农村的可持续发展,是广大规划人员必须关注和重视的问题。  相似文献   
89.
探索不同乳化剂sp60、sp80、tw60、tw80及其复合乳化剂对坎利酮羟基化的影响。结果表明乳化剂对坎利酮有增溶作用,且tw80、复合乳化剂tw80—sp60对坎利酮微生物转化有促进作用。其中单组分乳化剂tw80的最佳质量分数为0.18%,转化率为90.32%;复合乳化剂tw80-sp60,最佳质量分数为0.09%,转化率为92.22%。  相似文献   
90.
The minced meat market in Belgium is growing steadily; its share of the market has increased from 10 to 30% in three years. However, the mincing of meat can produce intense microbiol proliferation and thus cause food putrification.Any changes occurring in meat, especially minced meat, are essentially of microbial origin, hence refrigeration is particularly important. With chilling, minimum temperatures must be maintained (0±1°C), since only temperatures below +3°C avoid any health risk linked with the growth of pathogens and production of toxins. Under chilled conditions the storage use of minced meat is four to five days. With freezing, temperatures of about - 18°C are needed to avoid the growth of bacteria, yeasts and mould. At this temperature micro-organisms are progressively rendered inactive, but destruction is never total. The kinetics of reducing micro-organism populations depends on the nature of the micro-organisms, the storage temperature (reduction is more intense at − 12°C that at − 18°C or at − 30°C) and the freezing rate (micro-organisms are better able to resist rapid freezing than slow freezing). One years storage at − 18°C will destroy 90 to 99% of the micro-organisms which were initially present in the product. Nevertheless, the chilled storage (+4°C) of thawed minced meat must not exceed three days.The physico-chemical evolution of cold stored minced meat is explained. In chilled storage, the onset of flavour defects can be related to the measurement of volatile nitrogen. In frozen storage, the crystallisation of the water causes cellular breakdown. The role of packaging is important in avoiding superficial freeze-drying which is accompanied by browning. In addition, fatty matter can deteriorate by oxidation even at freezing temperatures. The degree of alteration of fats can be appreciated by the acidity index and peroxide index (showing that it is undesirable to store minced pork at − 18°C for more than nine months).Use of a partial vacuum or modified atmosphere in combination with impermeable packaging will prolong the storage life of minced meat provided that the initial contamination is as low as possible and the maintenance of the cold chain is strictly respected.

Résumé

Le marché de la viande hachée progresse en Europe, du fait de plusieurs facteurs socio-économiques. Le hachage diminue considérablement la durée de conservation de la viande; sa consommation peut être dangereuse.L'article analyse les points suivants: emballage, réfrigération et congélation (notamment vitesse de congélation), température et durée de conservation, atmosphères modifiées et leur influence sur les propriétés physico-chimiques de la viande et sur le comportement microbien.  相似文献   
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