全文获取类型
收费全文 | 2950篇 |
免费 | 61篇 |
国内免费 | 4篇 |
专业分类
电工技术 | 38篇 |
综合类 | 2篇 |
化学工业 | 758篇 |
金属工艺 | 46篇 |
机械仪表 | 69篇 |
建筑科学 | 117篇 |
矿业工程 | 1篇 |
能源动力 | 93篇 |
轻工业 | 280篇 |
水利工程 | 24篇 |
石油天然气 | 3篇 |
无线电 | 267篇 |
一般工业技术 | 452篇 |
冶金工业 | 156篇 |
原子能技术 | 19篇 |
自动化技术 | 690篇 |
出版年
2024年 | 50篇 |
2023年 | 56篇 |
2022年 | 147篇 |
2021年 | 181篇 |
2020年 | 100篇 |
2019年 | 94篇 |
2018年 | 118篇 |
2017年 | 70篇 |
2016年 | 142篇 |
2015年 | 89篇 |
2014年 | 129篇 |
2013年 | 205篇 |
2012年 | 182篇 |
2011年 | 236篇 |
2010年 | 144篇 |
2009年 | 150篇 |
2008年 | 152篇 |
2007年 | 125篇 |
2006年 | 110篇 |
2005年 | 84篇 |
2004年 | 63篇 |
2003年 | 59篇 |
2002年 | 42篇 |
2001年 | 23篇 |
2000年 | 27篇 |
1999年 | 30篇 |
1998年 | 42篇 |
1997年 | 37篇 |
1996年 | 33篇 |
1995年 | 15篇 |
1994年 | 19篇 |
1993年 | 9篇 |
1992年 | 10篇 |
1991年 | 2篇 |
1990年 | 1篇 |
1989年 | 6篇 |
1988年 | 3篇 |
1985年 | 2篇 |
1984年 | 1篇 |
1983年 | 3篇 |
1982年 | 4篇 |
1981年 | 2篇 |
1980年 | 6篇 |
1979年 | 4篇 |
1977年 | 1篇 |
1976年 | 3篇 |
1974年 | 1篇 |
1972年 | 1篇 |
1969年 | 1篇 |
1965年 | 1篇 |
排序方式: 共有3015条查询结果,搜索用时 15 毫秒
31.
Caroline Hoad Phillippa Rayment Vincent Risse Eleanor Cox Elisabetta Ciampi Stive Pregent Luca Marciani Michael Butler Robin Spiller Penny Gowland 《Food Hydrocolloids》2011
This paper describes an in vivo study of the use of encapsulation to alter lipid bio-accessibility in the gastro-intestinal (GI) tract. The hypothesis that encapsulation would delay the accessibility of lipid in the GI tract was tested using subjects (N = 11) who consumed either 30 g of 13C-labelled sunflower oil encapsulated within 70 g alginate gel particles, or unencapsulated ‘free’ sunflower oil and alginate-only particles (control). Lipid accessibility was determined by the appearance of the 13C label in breath carbon-dioxide (CO2), and the particles behaviour in the GI tract was investigated using non-invasive magnetic resonance imaging (MRI). 相似文献
32.
Manzano M Cocolin L Iacumin L Cantoni C Comi G 《International journal of food microbiology》2005,101(3):333-339
In this paper new primers, annealing to the ITS2 region, were used to obtain a PCR product that was subsequently subjected to Temperature Gradient Gel Electrophoresis (TGGE) analysis. The PCR-TGGE method performed was able to distinguish Saccharomyces cerevisiae and S. paradoxus and distinguish between strains of S. cerevisiae. Direct analysis of S. cerevisiae and S. paradoxus ecology in musts were also performed. 相似文献
33.
In this study the satiating capacity of three beverages containing 3 g barley β-glucan, or 2.5 g dietary fibre (DF) from fruit, or without DF (control) was evaluated. Fourteen healthy volunteers were randomized to have isocaloric breakfasts including one of the beverages in different occasions. Appetite ratings over 3 h post-breakfast and energy intakes at ad libitum lunch, blood glucose, insulin, ghrelin, PYY, GLP-1, GIP, and PP concentrations, and 24 h food intake, were assessed. The bevaerages containing DF increased fullness and satiety over 3 h post-breakfast, but only the β-glucan-enriched vs. the control significantly reduced energy intakes by 18% at lunch and 40% over the rest of the day. Blood ghrelin and PP responses were differently modulated by beverages. The fruit-based and the β-glucan-enriched beverage suppressed by 8.9% and 8.1% ghrelin response over the 3 h and the first hour post-breakfast, respectively, while only the latter increased PP response by 34.6%, compared to the control. A sucrose-sweetened beverage providing 3 g barley β-glucans can control food intake by modulating PP response and it can even reduce 24 h energy intake. Ghrelin suppression by fruit dietary fibre and mixed sugars was not sufficient to significantly reduce food intake compared to the control. 相似文献
34.
Luca Cacchiarelli Tiziana Laureti Alessandro Sorrentino 《Journal of Wine Research》2014,25(4):281-297
The purpose of the paper is to contribute to understanding the role and effectiveness of different quality clues in the creation of value for the main wines of the Lazio region. The study presents a hedonic price model. An ordinary least squares and a quantile regression models were estimated. The latter is able to detect additional patterns related to the effects of the covariates. Prices are regressed on wine color, sub-regional area of origin, the type of certification of origin, and on experts' evaluation. The analysis is based on data released by three major Italian wine guides: Gambero Rosso, l'Espresso, and AIS (Italian Sommelier Association). Results show that: (i) white and red wines follow two different price patterns; (ii) prices are correlated with experts' evaluation; (iii) the impact of the latter is higher when other quality clues, such as geographical indications, are less effective; (iv) the role of different quality clues varies at different price levels and it is different for red and white wines; overall, wines from the Lazio region are associated with poor to mediocre quality levels. This may explain the decline in reputation and in market share that these wines are experiencing after centuries of popularity. 相似文献
35.
Accumulation parameters and seasonal trends for PCBs in temperate and boreal forest plant species 总被引:1,自引:0,他引:1
Nizzetto L Pastore C Liu X Camporini P Stroppiana D Herbert B Boschetti M Zhang G Brivio PA Jones KC Di Guardo A 《Environmental science & technology》2008,42(16):5911-5916
The concentration of polychlorinated biphenyls (PCBs) in the air and vegetation was measured periodically in two alpine forests, during the growing season. Foliage samples from nine plant species typical of the temperate and boreal environment were collected and analyzed. Leaf concentrations of tri- and tetra-CBs showed fast response times with changing temperature and gas-phase concentrations, suggesting that a partitioning equilibrium is approached relatively rapidly (few days) in the field. Heavier compounds showed kinetically limited accumulation trends, not reaching equilibrium during the growing season. Results were used to estimate the bioconcentration factors or equilibrium plant/air partition coefficient (KPA) for each species. Values of log KPA (calculated on a mass/volume basis) ranged between 0.78 and 1.96 and were correlated to the log KOA. Uptake trends of the higher chlorinated compounds showed intraspecific differences which were partially explained by the specific leaf area (SLA). 相似文献
36.
Lucilla Iacumin Luca Chiesa Daria Boscolo Marisa Manzano Carlo Cantoni Sandi Orlic Giuseppe Comi 《Food microbiology》2009
The use of moulds as a seasoning for sausage can have both desirable and undesirable consequences. The desirable consequences are the creation of a successful product that appeals to consumers. The undesirable consequences are due to the growth of undesirable moulds that produce highly toxic secondary metabolites referred to as mycotoxins. The aim of the paper was to investigate the presence of moulds producing ochratoxin A (OTA) on the surface of sausages from northern Italy. A total of 757 mould strains were isolated from sausage casings. The most frequently identified species were Penicillium nalgiovense, Penicillium oxalicum, Eurotium amstelodami, Penicillium olsonii, Penicillium chrysogenum, Penicillium verrucosum, Penicillium viridicatum, and Eupenicillium crustaceum. Aspergillus ochraceus was detected in only one production lot. Approximately 45% of these samples were positive for the presence of OTA. On the casings of the investigated sausages, the lowest and highest OTA values were 3 and 18 μg/kg, respectively. The OTA concentration was reduced to below the limit of detection (LOD) by brushing and washing the sausages prior to sale. From these data it appears that the presence of OTA on the surface of sausage (on the casings) is not indicative of any health risk for human consumption of sausage, since OTA was not identified inside the dry meat. 相似文献
37.
Thomsen Maria Carmignani Luca Rodriguez Andy Scudiere Charles Liveretou Christina Fernandez-Pello Carlos Gollner Michael Olson Sandra Ferkul Paul 《Fire Technology》2022,58(4):2229-2250
Fire Technology - There are multiple situations in which fires may occur at environmental conditions that are different than standard atmospheric conditions. Changes in ambient pressure, oxygen... 相似文献
38.
The unsteady-state kinetics of the selective catalytic reduction (SCR) of NO with NH3 is studied over V2O5–WO3/TiO2 model catalysts by means of the transient response method. NH3 strongly adsorbs onto the catalyst surface whereas NO does not adsorb appreciably. A dynamic mathematical model based on a Temkin-type desorption process for NH3 and a SCR reaction rate with a complex dependence on the ammonia surface coverage is well suited to represent the data. 相似文献
39.
Identification and Structure–Activity Relationship Studies of Small‐Molecule Inhibitors of the Methyllysine Reader Protein Spindlin1
下载免费PDF全文

Dr. Dina Robaa Dr. Tobias Wagner Chiara Luise Dr. Luca Carlino Joel McMillan Dr. Ralf Flaig Prof. Dr. Roland Schüle Prof. Dr. Manfred Jung Prof. Dr. Wolfgang Sippl 《ChemMedChem》2016,11(20):2327-2338
The methyllysine reader protein Spindlin1 has been implicated in the tumorigenesis of several types of cancer and may be an attractive novel therapeutic target. Small‐molecule inhibitors of Spindlin1 should be valuable as chemical probes as well as potential new therapeutics. We applied an iterative virtual screening campaign, encompassing structure‐ and ligand‐based approaches, to identify potential Spindlin1 inhibitors from databases of commercially available compounds. Our in silico studies coupled with in vitro testing were successful in identifying novel Spindlin1 inhibitors. Several 4‐aminoquinazoline and quinazolinethione derivatives were among the active hit compounds, which indicated that these scaffolds represent promising lead structures for the development of Spindlin1 inhibitors. Subsequent lead optimization studies were hence carried out, and numerous derivatives of both lead scaffolds were synthesized. This resulted in the discovery of novel inhibitors of Spindlin1 and helped explore the structure–activity relationships of these inhibitor series. 相似文献
40.
Additive Manufacturing of Ceramics Enabled by Flash Pyrolysis of Polymer Precursors with Nanoscale Layers
下载免费PDF全文

Luca Zoli Diletta Sciti Li‐Anne Liew Kalvis Terauds Setareh Azarnoush Rishi Raj 《Journal of the American Ceramic Society》2016,99(1):57-63
We show that a polymer‐based route to ceramics can be implemented into additive manufacturing by reducing the time for pyrolysis to about a second, which we call flash pyrolysis. Repetitive deposition of nanometer scale coatings of the ceramic, in this way, is employed to create defect‐free infiltrations of carbon fiber composites. The mechanical strength of the fibers is retained in the composite. Excellent wetting properties of the polymer precursor permits three‐dimensional, conformal coating through the three stages of infiltration: nanoscale coating of the single fibers, filling of interstitial spaces between the fibers, and a buildup of the coating over the entire composite. The flash pyrolysis method will enable a new genre of polymer‐derived ceramics made into net shape by this unusual method of additive manufacturing. 相似文献