全文获取类型
收费全文 | 1110篇 |
免费 | 85篇 |
国内免费 | 3篇 |
专业分类
电工技术 | 5篇 |
化学工业 | 464篇 |
金属工艺 | 12篇 |
机械仪表 | 18篇 |
建筑科学 | 38篇 |
矿业工程 | 1篇 |
能源动力 | 34篇 |
轻工业 | 130篇 |
水利工程 | 7篇 |
石油天然气 | 3篇 |
武器工业 | 1篇 |
无线电 | 57篇 |
一般工业技术 | 179篇 |
冶金工业 | 128篇 |
原子能技术 | 7篇 |
自动化技术 | 114篇 |
出版年
2023年 | 19篇 |
2022年 | 105篇 |
2021年 | 101篇 |
2020年 | 25篇 |
2019年 | 36篇 |
2018年 | 37篇 |
2017年 | 43篇 |
2016年 | 57篇 |
2015年 | 34篇 |
2014年 | 49篇 |
2013年 | 86篇 |
2012年 | 62篇 |
2011年 | 66篇 |
2010年 | 58篇 |
2009年 | 50篇 |
2008年 | 48篇 |
2007年 | 33篇 |
2006年 | 31篇 |
2005年 | 29篇 |
2004年 | 17篇 |
2003年 | 18篇 |
2002年 | 9篇 |
2001年 | 8篇 |
2000年 | 12篇 |
1999年 | 9篇 |
1998年 | 40篇 |
1997年 | 34篇 |
1996年 | 25篇 |
1995年 | 11篇 |
1994年 | 10篇 |
1993年 | 9篇 |
1992年 | 4篇 |
1991年 | 1篇 |
1990年 | 5篇 |
1989年 | 2篇 |
1988年 | 2篇 |
1985年 | 1篇 |
1983年 | 1篇 |
1980年 | 1篇 |
1979年 | 1篇 |
1976年 | 1篇 |
1975年 | 3篇 |
1974年 | 1篇 |
1973年 | 1篇 |
1970年 | 1篇 |
1966年 | 1篇 |
1965年 | 1篇 |
排序方式: 共有1198条查询结果,搜索用时 15 毫秒
991.
992.
Nirakar Pradhan Laura Dipasquale Giuliana dIppolito Antonio Panico Piet N.L. Lens Giovanni Esposito Angelo Fontana 《International Journal of Hydrogen Energy》2017,42(25):16023-16030
Thermotoga neapolitana is a hyperthermophilic eubacterium that produces hydrogen by sugar fermentation. A lab strain of T. neapolitana DSMZ 4359T maintained in a CO2-enriched atmosphere showed a stable increase of lactic acid production under capnophilic lactic fermentation (CLF) conditions. The genotypic comparison between the putative mutant (TN-CMut) and the original strain DSMZ 4359T (WT4359) revealed 88.1 (±2.4)% DNA homology. RiboPrint® and MALDI-TOF mass analyses support a genetic differentiation beyond subspecies level. The phenotypic characterization indicated a high correlation between the two strains, except for the lactic acid production. Under identical operating conditions, the lab mutant produced significantly more lactic acid than the parent strain without impairing the hydrogen yield. The highest divergence between TN-CMut and WT4359 was observed for fermentation of glucose or lactose at 80 °C. Based on these results, we propose that the lab strain is a new subspecies of the genus Thermotoga that is named T. neapolitana subsp. capnolactica with regards to its improved feature to produce lactic acid under capnophilic conditions. 相似文献
993.
Jéssica Bassi da Silva Sabrina Barbosa de Souza Ferreira Osvaldo de Freitas 《Drug development and industrial pharmacy》2017,43(7):1053-1070
Mucoadhesion is a useful strategy for drug delivery systems, such as tablets, patches, gels, liposomes, micro/nanoparticles, nanosuspensions, microemulsions and colloidal dispersions. Moreover, it has contributed to many benefits like increased residence time at application sites, drug protection, increased drug permeation and improved drug availability. In this context, investigation into the mucoadhesive properties of pharmaceutical dosage forms is fundamental, in order to characterize, understand and simulate the in vivo interaction between the formulation and the biological substrate, contributing to the development of new mucoadhesive systems with effectiveness, safety and quality. There are a lot of in vivo, in vitro and ex vivo methods for the evaluation of the mucoadhesive properties of drug delivery systems. However, there also is a lack of standardization of these techniques, which makes comparison between the results difficult. Therefore, this work aims to show an overview of the most commonly employed methods for mucoadhesion evaluation, relating them to different proposed systems and using artificial or natural mucosa from humans and animals. 相似文献
994.
995.
Irene Oddone Daniele Fulginiti Antonello A. Barresi Sabrina Grassini 《Drying Technology》2015,33(13):1621-1630
In this study, a new technology, based on the use of an array of thin-film thermocouples, is proposed for the real-time and non-invasive monitoring of product temperature during a freeze-drying cycle. This array of thin-film thermocouples was demonstrated to give quantitative accurate results without altering the freezing and drying behavior of the monitored vials, making this sensor a good alternative to conventional wire thermocouples. Furthermore, unlike conventional thermocouples, the array of thin-film thermocouples can measure the entire temperature profile within the product being dried and can also measure the position of the interface of sublimation. This information was then used to estimate the heat and mass transfer coefficient of the system under investigation, showing a fairly good agreement with data obtained by conventional, time-consuming procedures. Finally, it is shown how these parameters can be used to guide the lyophilization professional during the cycle development. 相似文献
996.
Mariana Volpato Junqueira Fernanda Belincanta Borghi-Pangoni Sabrina Barbosa de Souza Ferreira 《Drug development and industrial pharmacy》2016,42(12):2009-2019
This study describes the investigation about the physicochemical behavior of methylene blue (Mb) addition to systems containing poloxamer 407 (Polox), Carbopol 934P (Carb), intended to be locally used by photodynamic therapy. A factorial design 23 (plus center point) was used to analyze the rheological, mucoadhesive and textural properties of the preparations. Systems containing the lower concentrations of Polox (15 and 17.5%, w/w) exhibited pseudoplastic flow and low degrees of rheopexy. On the other hand, at higher Polox concentration (20%, w/w) the systems display plastic flow and thixotropy. Carb and Mb exhibited a negative influence for the consistency and flow behavior index, due to the interaction between them. For most of the formulations, the increase of Polox and Mb content significantly increased storage modulus, loss modulus and dynamic viscosity. The systems display a sol–gel transition temperature, existing as a liquid at room temperature and gel at 29–37?°C. Increasing the temperature and the polymer concentration, the compressional properties of systems significantly increased. The mucoadhesion was noted to all formulations, except to systems composed by 15% (w/w) of Polox. The analyses enabled to understand and predict the performance of formulations and the polymer–Mb interactions, tailoring to the suit systems (Polox/Carb/Mb): 17.5/0.50/0.20 and 20/0.15/0.25. 相似文献
997.
Effect of inulin on growth and bacteriocin production by Lactobacillus plantarum in stationary and shaken cultures
下载免费PDF全文
![点击此处可从《International Journal of Food Science & Technology》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Sabrina da Silva Sabo Attilio Converti Svetoslav Dimitrov Todorov José Manuel Domínguez Ricardo Pinheiro de Souza Oliveira 《International Journal of Food Science & Technology》2015,50(4):864-870
The prebiotic effect of inulin added to MRS medium on growth and bacteriocin production by L. plantarum ST16 Pa was investigated in stationary cultures in anaerobic jars with medium containing 0.025% sodium thioglycolate or in flasks shaken at 100 rpm. In the presence of 1% inulin in anaerobic stationary cultures, this strain produced lactic acid at a level that was 36.5% higher than in the absence of the polysaccharide. In shaken cultures without inulin, cell count was 54% higher than in the stationary ones. Under stationary conditions in anaerobic jars, the addition of inulin increased the maximum specific growth rate from 0.37 to 0.49 h?1 and reduced the generation time from 1.85 h to 1.40 h. Consequently, the exponential phase was shortened from 12 to 9 h when the cells were grown in stationary cultures with the oxygen scavenger. Despite this effect of inulin on growth rate, stationary cultures without inulin displayed higher antimicrobial activity against Listeria monocytogenes L104 (3200 AU/mL) than cultures with inulin (1600 AU/mL); therefore, inulin behaved as a compound able to accelerate growth rather than to stimulate bacteriocin production. The results presented in this study are very promising, as L. monocytogenes is a well‐known foodborne pathogenic microorganism. Moreover, L. plantarum ST16 Pa has proven to be a potential producer of a natural food preservative at an industrial level. 相似文献
998.
Gianni Pastore Antonio D'Aloise Sabrina Lucchetti Mariateresa Maldini Elisabetta Moneta Marina Peparaio Antonio Raffo Fiorella Sinesio 《LWT》2014
Quality and composition of virgin olive oil (VOO) are strictly dependent on complex processes that take place during the olive fruit crushing and malaxation of the olive paste. In this work, modulation of O2 levels within malaxation chambers (R1: unmodified atmosphere; R2: oxygen: 12.73–4.64 kPa from the beginning to the end of malaxation; R3: 10.46–2.27 kPa; R4: 9.87–0.69 kPa) in two continuous “two-phase” and “three-phase” oil extraction plants was performed. Combined effects on the biosynthesis of nutritionally bioactive molecules and aroma volatiles and on the resulting sensory properties of the produced oils were investigated. Results showed that the type of oil extraction plant markedly affected the level of the phenolic compounds in the oil (and the related sensory attributes of bitter, pungency, astringency and bitter and pungency persistence). Reduction of O2 concentration in the malaxing chamber, while having a minor impact on the presence of phenolic compounds, significantly affected the formation of all the examined volatiles. Particularly, lowered levels of oxygen hindered the formation of lipoxygenase derived volatiles weakening odours and flavours of artichoke, fresh fruity, and fresh cut grass. 相似文献
999.
1000.
Under the umbrella concept of conviviality in public spaces, a research project on the rehabilitation of urban areas for commercial and retail uses---as engine of a complex process of production of places for social and cultural mixit6--has been defined. The aim of this research has been to produce useful tools for coping with the abandonment of public spaces in former commercial urban areas, without generating anonymous and globalized commercial districts. Through involving local stakeholders in a participatory process, the first phase of the research here presented needs to demonstrate the possible effectiveness of a pilot action plan in dealing with both isolation and gentrification processes of historical centres. The main hypothesis is that traditional retailers should be considered an essential element to ensure effective public use of urban public spaces. The research methodology is based on a qualitative approach. Focussing on the process of impoverishment within local commercial districts, the research group started working with local stakeholders in order to identify priorities and criticisms for enhancing a regeneration process. The case study to be carried out in Naples is the historical market place of Piazza Mercato in the Citth Bassa of Naples (Italy). 相似文献