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排序方式: 共有499条查询结果,搜索用时 15 毫秒
491.
492.
The consumer's role in the packaging value chain thinking has increased. This paper identifies the basic functions of packaging as well as the importance of the visual and structural elements from the consumer's view. However, it is unclear what packaging experts associate with consumers' packaging interactions. Professionals working in the field are still in the key position of defining directions in the packaging industry. The paper investigates how professionals perceive consumer interactions with packaging, and identifies challenges in consumer‐centred packaging development. The research materials were collected from 14 theme interviews with representatives of higher education, packaging research and packaging design agencies. As a result, five narratives and five challenges for consumer‐centred packaging development were constructed. The narratives describe the following: (a) the symbiotic product–packaging relationship; (b) the everyday context highlighted in purchase and use situations; (c) how consumers become aware of packages; (d) a fashion system of packaging; and (e) everyday routines and rituals involving packaging. The aims of the paper are to raise the awareness of how professionals perceive consumer interaction with packaging, to provide insight into factors relevant for consumer‐centred packaging development in industry and to identify the potential challenges, from the professionals' view, for adopting a consumer‐centred model. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
493.
The water absorption of sapwood and heartwood of Scots pine and Norway spruce heat-treated at 170 °C, 190 °C, 210 °C and 230 °C 总被引:2,自引:0,他引:2
Sini Metsä-Kortelainen Toni Antikainen Pertti Viitaniemi 《Holz als Roh- und Werkstoff》2006,64(3):192-197
Heat-treatment changes the chemical and physical properties of wood. Wood polymers are degraded, dimensional stability is enhanced, equilibrium moisture content is lowered, colour darkens and biological durability is increased. The properties of heat-treated wood have been researched considerably, but the differences between sapwood and heartwood have not been reported separately. In this research, water absorption differences between sapwood and heartwood of Scots pine and Norway spruce heat-treated at temperatures 170 °C, 190 °C, 210 °C and 230 °C were investigated. The results were compared to industrially kiln-dried reference samples. Water absorption was determined with a floating test based on the EN 927-5 standard. The heartwood of both wood species absorbed less water than sapwood. Heat-treatment evidently decreased the water absorption of spruce and pine heartwood. The higher the heat-treating temperature, the lower the amount of absorbed moisture. However, a very interesting exception was pine sapwood, whose water absorption actually increased with heat-treatment after the three lowest heat-treatment temperatures compared to the reference material. Water absorption did not decrease until the heat-treatment temperature was 230 °C. 相似文献
494.
Pieter Gouws Toni Hartel Rudean van Wyk 《Journal of the science of food and agriculture》2014,94(15):3069-3078
This review discusses the influence of processing on the microbial risk associated with Salmonella in Rooibos tea, the identification of Salmonella and preventative and control measures to control microbial contamination. Rooibos tea, like other plant products, naturally contains a high microbial load. Downstream processing steps of these products usually help in reducing any contaminants present. Due to the delicate flavour properties and nature of Rooibos, gentle processing techniques are necessary for the production of good quality tea. However, this has a major influence on the microbiological status of the product. The presence of Salmonella in Rooibos is poorly understood. The ubiquitous distribution of Salmonella in the natural environment and its prevalence in the global food chain, the physiological adaptability, virulence of the bacterial pathogen and its serious economic impact on the food industry, emphasises the need for continued awareness and stringent controls at all levels of food production. With the advances of technology and information at hand, the processing of Rooibos needs to be re‐evaluated. Since the delicate nature of Rooibos prohibits the use of harsh methods to control Salmonella, alternative methods for the steam pasteurisation of Rooibos show great potential to control Salmonella in a fast, efficient and cost‐effective manner. These alternative methods will significantly improve the microbiological quality of Rooibos and provide a product that is safe to consumers. © 2014 Society of Chemical Industry 相似文献
495.
Elisa Maffioli Elisa Angiulli Simona Nonnis Francesca Grassi Scalvini Armando Negri Gabriella Tedeschi Ivan Arisi Flavia Frabetti Salvatore DAniello Enrico Alleva Carla Cioni Mattia Toni 《International journal of molecular sciences》2022,23(10)
Experimental evidence suggests that environmental stress conditions can alter the expression of BDNF and that the expression of this neurotrophin influences behavioural responses in mammalian models. It has been recently demonstrated that exposure to 34 °C for 21 days alters the brain proteome and behaviour in zebrafish. The aim of this work was to investigate the role of BDNF in the nervous system of adult zebrafish under control and heat treatment conditions. For this purpose, zebrafish from three different genotypes (wild type, heterozygous BDNF+/− and knock out BDNF−/−) were kept for 21 days at 26 °C or 34 °C and then euthanized for brain molecular analyses or subjected to behavioural tests (Y-maze test, novel tank test, light and dark test, social preference test, mirror biting test) for assessing behavioural aspects such as boldness, anxiety, social preference, aggressive behaviour, interest for the novel environment and exploration. qRT-PCR analysis showed the reduction of gene expression of BDNF and its receptors after heat treatment in wild type zebrafish. Moreover, proteomic analysis and behavioural tests showed genotype- and temperature-dependent effects on brain proteome and behavioural responding. Overall, the absent expression of BDNF in KO alters (1) the brain proteome by reducing the expression of proteins involved in synapse functioning and neurotransmitter-mediated transduction; (2) the behaviour, which can be interpreted as bolder and less anxious and (3) the cellular and behavioural response to thermal treatment. 相似文献
496.
(续接本刊2007年第11期第42页)
3中国、印度和南非的电子废物管理及评述
3.1发展中国家和转型期国家面临的特殊问题
上面已经提到了部分发展中国家和转型期国家面临的特殊问题,总结如下:
①尽管国内人均电子废物的产生量仍相对较小,但对于人口大国而言,如中国和印度,电子废物的绝对产生量大(Empa,2005).
…… 相似文献
497.
Nea Repar Eva Jarc Jovi
i Ana Kump Giovanni Birarda Lisa Vaccari Andreja Erman Slavko Kralj Sebastjan Nemec Toni Petan Damjana Drobne 《International journal of molecular sciences》2022,23(13)
Superparamagnetic iron oxide nanoparticles (SPIONs) have great potential for use in medicine, but they may cause side effects due to oxidative stress. In our study, we investigated the effects of silica-coated SPIONs on endothelial cells and whether oleic acid (OA) can protect the cells from their harmful effects. We used viability assays, flow cytometry, infrared spectroscopy, fluorescence microscopy, and transmission electron microscopy. Our results show that silica-coated SPIONs are internalized by endothelial cells, where they increase the amount of reactive oxygen species (ROS) and cause cell death. Exposure to silica-coated SPIONs induced accumulation of lipid droplets (LD) that was not dependent on diacylglycerol acyltransferase (DGAT)-mediated LD biogenesis, suggesting that silica-coated SPIONs suppress LD degradation. Addition of exogenous OA promoted LD biogenesis and reduced SPION-dependent increases in oxidative stress and cell death. However, exogenous OA protected cells from SPION-induced cell damage even in the presence of DGAT inhibitors, implying that LDs are not required for the protective effect of exogenous OA. The molecular phenotype of the cells determined by Fourier transform infrared spectroscopy confirmed the destructive effect of silica-coated SPIONs and the ameliorative role of OA in the case of oxidative stress. Thus, exogenous OA protects endothelial cells from SPION-induced oxidative stress and cell death independent of its incorporation into triglycerides. 相似文献
498.
499.
Sedimentation Field Flow Fractionation in combination with multi angle laser light scattering was applied to fully destructured potato and waxy corn starches to investigate the molecular weight and radius distributions of the starch components. In a range of radii betwen 50 and 500nm, information could be obtained about the influence of the medium conditions on the distributions. The averages of molecular weight and particle radius were found to decrease when holding the solution at a given temperature for an extended period of time (from 20min up to 60min) and when the temperature was increased (from 160°C up to 175°C). The molecular weight and radii of gyration of the dissolved starch species typically panged from 106 to 109 daltons and 50nm-500nm respectively. Changes in the distributions due to different conditions during the dissolution process where also recognized by changes in the shape of the distribution curve. Thus the applied technique gave satisfactory results in a high molecular weight region where SEC fails. 相似文献