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61.
62.
Dry cured sausages such as Portuguese chouriço de vinho are made generally with roughly minced pork and fat and seasoned with a large variety of herbs and spices. It is a particular sausage because meat is marinated in wine with other seasonings during 24–48 h before stuffing. Nowadays, health concerns of consumers have left food processors with less flexibility to choose preservative substances and methods. Thus, the objective of this study was to assess the antimicrobial effect of essential oils (EOs) of herbs and spices traditionally used in seasoning dry cured sausage chouriço against Salmonella spp., Listeria monocytogenes and Staphylococcus aureus. First, antibacterial activity of 14 EOs was screened by disk diffusion assay. Those EOs that displayed antimicrobial activity were further characterized by GC–MS and added as natural antimicrobial substances to the manufacture of chouriço at two concentrations (0.005% and 0.05%). Samples were analyzed 24 h after the preparation of the batter and after 3, 8, 15 and 21 days.After 15 days of drying, Salmonella spp. and L. monocytogenes counts decreased by ca. 2 log cfu/g in all samples. At 3 days, Salmonella spp. was already undetectable in chouriço made with 0.05% of garlic and oregano EOs. Both Salmonella spp. and L. monocytogenes were not detected after 8 and 15 days of drying respectively. S. aureus was still presented after 21 days of drying although its counts were not high enough to a potential enterotoxins presence. Utilization of EOs in manufacture of dry cured sausage resulted in an interesting strategy to improve its safety against Salmonella spp, L. monocytogenes and S. aureus, but with sensory limitations, that does not allow its use in high concentrations, that are those more interesting for pathogen inhibition.However, results with good potential to be applied by the industry were found, once the level of addition of 0.005% contributed for significant reductions on the pathogen's counts and for a shorter period to achieve the not detectable level, allowing the industry to shorten the drying period and, thereafter increasing yield production.  相似文献   
63.
Following the discovery of horsemeat in beef products in Europe in 2013, restoring consumers' confidence in processed meat products as well as in all the agencies involved – producers, food safety authorities, retailers – soon became a key priority. However, the European public's confidence in processed meat products and their views about government and industry actions to manage fraudulent practices in the wake of this incident are poorly understood. The objective of this study was to identify the core issues affecting consumers' confidence in the food industry, particularly in the meat processing sector, and to explore the impact of the horsemeat incident on consumers' purchasing and eating behaviour. It involved the use of an online deliberation tool VIZZATA™ to collect detailed views of 61 consumers in the UK and the Republic of Ireland. Many participants reported buying fewer products containing processed meat as a result of the horsemeat incident. These respondents also claimed that their confidence in processed foods containing meat was lower than before the incident. Participants suggested restoring consumer confidence through improved traceability, sourcing local ingredients, providing clearer and correct labelling and stating the origin of meat on pack. Overall, findings indicate that rebuilding consumer confidence in processed meat products following a food adulteration episode is a multifaceted and difficult process. Food authorities and the food industry can benefit from the insights provided by this study to address issues affecting consumer confidence and to improve their communication strategies during future food adulteration incidents.  相似文献   
64.
We investigated whether consumer preferences for beef colors (red, purple, and brown) or for beef packaging systems (modified atmosphere, MAP; vacuum skin pack, VSP; or overwrap with polyvinyl chloride, PVC) influenced taste scores of beef steaks and patties. To test beef color effects, boneless beef top loin steaks (choice) and ground beef patties (20% fat) were packaged in different atmospheres to promote development of red, purple, and brown color. To test effects of package type, steaks and patties were pre-treated with carbon monoxide in MAP to promote development of red color, and some meat was repackaged using VSP or PVC overwrap. The differently colored and packaged meats were separately displayed for members of four consumer panels who evaluated appearance and indicated their likelihood to purchase similar meat. Next, the panelists tasted meat samples from what they had been told were the packaging treatments just observed. However, the meat samples actually served were from a single untreated steak or patty. Thus, any difference in taste scores should reflect expectations established during the visual evaluation. The same ballot and sample coding were used for both the visual and taste evaluations. Color and packaging influenced (P<0.001) appearance scores and likelihood to purchase. Appearance scores were rated red>purple >brown and PVC >VSP>MAP. Appearance scores and likelihood to purchase were correlated (r=0.9). However, color or packaging did not affect (P>0.5) taste scores. Thus, consumer preferences for beef color and packaging influenced likelihood to purchase, but did not bias eating satisfaction.  相似文献   
65.
Smart meters (SM) may provide large benefits to all stakeholders by providing the information required to implement certain sets of demand response actions. Benefits produced by SM related actions depend on the features of these actions, the system and the targeted consumer group.We first lay out an analytical framework to analyze the application of Demand Response (DR) actions. Based on this framework, we describe a way to determine the response of domestic load in a system to the implementation of DR actions. We propose determining the overall change in the consumption behavior of domestic load based on previously obtained estimates of the peak load and overall consumption reduction for different types of consumers in different types of systems resulting from the application of each set of actions. We have carried out a comprehensive literature review to provide here such estimates.We apply the analytical framework and methodology developed to characterize the reaction of consumers in the Austrian system to different SM related actions. Finally, we provide guidelines on which DR actions to implement in this system and how to implement them. The use of advanced indirect feedback on consumption behavior, critical peak prices and simple time-of-use tariffs is advocated.  相似文献   
66.
刚度、惯性负载对电液负载仿真台性能影响的研究   总被引:4,自引:1,他引:4  
为提高电液负载仿真台的性能 ,根据电液负载仿真台的数学模型 ,研究了电液负载仿真台中多余力矩的产生机理和影响因素 ,得出多余力矩干扰与舵机系统轴转角的速度、加速度有关的结论。在分析电液负载仿真台的刚度、惯性负载对系统性能影响的基础上 ,提出了电液负载仿真台的一些设计原则 ,为电液负载仿真台及其它被动加载系统的设计提供了参考依据。  相似文献   
67.
双阀控制在电液负载仿真台中的应用   总被引:2,自引:0,他引:2  
根据压力伺服阀和流量伺服阀在电液负载仿真台中的应用特点,提出一种由压力伺服阀和流量伺服阀组成的双阀控制加载方案。对比结构不变性原理补偿方法可知,此双阀控制方法在克服多余力矩及提高性能指标方面更有效。  相似文献   
68.
This paper identifies segments of Chinese consumers based on their perception of personal risk, how worried they are and their subjective knowledge about seven possible food-related hazards: additives, residues, counterfeit, inferior, genetically modified, deteriorated and nutritionally imbalanced food. Data were collected through a consumer survey conducted in Beijing (534 participants) and in Baoding (437 participants). Three clusters were identified: worried and knowledgeable consumers (60.1%), worried and ignorant consumers (21.7%) and moderately worried consumers (18.2%). The first two groups reported a high level of worry and high perception of personal risk about food-related hazards in China. The two hazards they were most worried about were counterfeit food and inferior quality food. Television, internet and personal communication were the three information channels most frequently used by participants to obtain information about food safety. Worried and ignorant consumers reported less frequent use of magazines, books and brochures compared with other consumers. Medical doctors, personal experience and research institutes were the three most trusted information sources for the first two groups of consumers. Moderately worried consumers only placed high levels of trust in medical doctors and themselves. Consumers' perceptions about the knowledge, honesty and concern of different information sources significantly and positively affected their trust in those sources. The study concludes by making recommendations as to how to improve communications with the different identified consumer segments and identifies future research required to expand its validity.  相似文献   
69.
Orissa is the first state in India to have undergone reform in the power sector, with the government withdrawing its control. The model of this reform is known as the WB–Orissa model. The goal of this paper is to examine the impact of this reform on consumers of electricity, which has been measured using multiple regression models. The variables represent the parameters that consumers are most interested in, and the regression coefficients represent the weights of the corresponding variables. The data were collected using a survey methodology. The impact of reform was found to be mixed. Some groups of consumers saw benefits, while others felt a negative impact. A focus group study was conducted to identify the variables of interest to consumers of electricity. The model was used to estimate consumer benefit and was validated using primary data and structural equation modeling. The study revealed beneficial aspects of reform and areas with no benefits.  相似文献   
70.
通过对喇嘛甸油田聚合物驱单井效果分析,给出了采油井阶段效果评价方法,即单井见效时间和含水回升时间早晚的确定方法,单井见效时间取决于油层条件,注聚前含油饱和度及累计采出地下体积倍数,单井含水回升时间主要取决于聚驱阶段剩余储量采出程度,根据单井阶段评价结果,对试验区进行跟踪调整,在单井阶段效果评价的基础上,对单井最终效果采用吨聚增油量和聚驱阶段剩余储量采收率来进行客观,有效的评价,对聚驱产量预测具有一定指导意义。  相似文献   
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