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991.
Zuhaib F. Bhat James D. Morton Susan L. Mason Alaa El‐Din A. Bekhit Hina F. Bhat 《Comprehensive Reviews in Food Science and Food Safety》2019,18(4):1192-1208
Defined as meat cultured in a laboratory within a bioreactor under controlled artificial conditions, in vitro meat is a relatively recent area that has opened a whole universe of possibilities and opportunities for the meat sector. With improved chemical and microbial safety and varied options, in vitro meat has been proposed as a green, healthy, environmentally friendly, and nutritionally better product that is free from animal suffering and death. Cell culture and tissue culture are the most probable technologies for the development of this futuristic muscle product. However, there are many challenges in the production of a suitable product at an industrial scale under a sustainable production system and a great body of research is required to fill the gaps in our knowledge. Many materials used in the product development are novel and untested within the food industry and demand urgent regulatory and safety assessment systems capable of managing any risks associated with the development of cultured meat. The future of this product will depend on the actions of governments and regulatory agencies. This article highlights emerging biotechnological options for the development of cultured meat and suggests ways to integrate these emerging technologies into meat research. It considers the problems and possibilities of developing cultured meat, opportunities, ethical issues as well as emerging safety and regulatory issues in this area. 相似文献
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994.
Rosana Chirinos David Campos Carlos Arbizu Hervé Rogez Jean‐François Rees Yvan Larondelle Giuliana Noratto Luis Cisneros‐Zevallos 《Journal of the science of food and agriculture》2007,87(3):437-446
The total phenolics, anthocyanins, flavan 3‐ols, carotenoids and antioxidant capacity of mashua (Tropaeolum tuberosum Ruiz & Pavón) tubers from 10 yellow and purple cultivars were determined at different maturity stages (5–7.5 months after planting) and sunning post‐harvest storage periods (7–35 days). Both the antioxidant capacity (ORAC and ABTS assays) and the content of the bioactive compounds tested varied markedly between cultivars. Purple varieties reached the highest antioxidant capacity during tuber development (271–446 µmol Trolox equiv g?1 DM, ORAC assay). The kinetics of accumulation or disappearance of the bioactive compounds tested during maturation was dependent both on the cultivar and on the compound considered. For anthocyanins, there was a marked increase during maturation in all the purple cultivars. During the sunning post‐harvest storage, the changes in antioxidant capacity (ABTS assay) and content of the bioactive compounds tested also varied between cultivars. A marked decrease in anthocyanins was observed for the anthocyanin‐containing cultivars. In general, the correlation between antioxidant capacity and the content of bioactive compounds varied markedly between cultivars. Antioxidant capacity in purple varieties correlated with total phenolics or flavan 3‐ols while only in some yellow varieties antioxidant capacity correlated with total phenolics. Copyright © 2007 Society of Chemical Industry 相似文献
995.
Yoon‐Suk Cho Kyung‐Jin Yeum Chung‐Yen Chen Giangiacomo Beretta Guangwen Tang Norman I Krinsky Sun Yoon Yang Cha Lee‐Kim Jeffrey B Blumberg Robert M Russell 《Journal of the science of food and agriculture》2007,87(6):1096-1107
The antioxidant activities of fruits (n = 21), vegetables (n = 67) and legumes (n = 7) commonly consumed in Korea were determined by both the lipophilic antioxidant performance assay (LAP) and the hydrophilic oxygen radical absorbance capacity assay (ORAC). The LAP assay used the lipophilic radical initiator MeO‐AMVN [2,2′‐azobis(4‐methoxy‐2,4‐dimethylvaleronitrile)] and the lipophilic probe BODIPY 581/591 [4,4‐difluoro‐5‐(4‐phenyl‐1,3‐butadienyl)‐4‐bora‐3a, 4a‐diaza‐s‐indacene‐3‐undecanoic acid]. The ORAC assay used the hydrophilic radical initiator AAPH [2,2′‐azobis(2‐amidinopropane) dihydrochloride] and the hydrophilic probe fluorescein. In addition, the lipid‐soluble phytonutrients, carotenoids and tocopherols were determined by a reverse‐phase HPLC system using a C30 column with a UV detector. The water‐soluble phytonutrient, ascorbic acid, was analyzed using an HPLC system with an electrochemical detector. Total phenols were determined by UV spectrophotometry. Tocopherols (r = 0.774, p < 0.0001) and carotenoids (r = 0.569, p < 0.0001) were significantly correlated with LAP in total samples (n = 95). ORAC was significantly correlated with total phenols (r = 0.893, p < 0.0001), but not with ascorbic acid (r = 0.009, p = 0.929) in total samples (n = 95). These data indicate that carotenoids and tocopherols and total phenols are the major contributors to the lipophilic and hydrophilic antioxidant capacities, respectively. Therefore, the contribution of both the hydrophilic and lipophilic components of fruits and vegetables should be considered when determining the actual ‘total’ antioxidant activity of fruits and vegetables. Copyright © 2007 Society of Chemical Industry 相似文献
996.
Kiyoka Higashi‐Okai Makoto Taniguchi Yasuji Okai 《Journal of the science of food and agriculture》2000,80(1):117-120
The antioxidative activity of green tea‐derived polyphenols known as catechins has been extensively studied. However, the antioxidative activity of the non‐polyphenolic fraction of green tea has been poorly elucidated and is the subject of the present study. The non‐polyphenolic fraction of green tea showed a significant dose‐dependent suppressive effect against the autooxidation of linoleic acid. The chlorophyll‐related compounds pheophytins a and b showed similar antioxidative activities in the same assay, much higher than those of α‐tocopherol and the green tea catechin (−)‐epigallocatechin‐3‐gallate (EGCG). The non‐polyphenolic fraction of green tea and pheophytins a and b exhibited suppressive activities against superoxide anion (${\bf O}_{2}ˆ{‐}$ ) generation in mouse macrophages induced by 12‐O‐tetradecanoylphorbol‐13‐acetate, showing higher activities than that of EGCG. These results suggest that the non‐polyphenolic fraction of green tea leaves has potent antioxidative activity and that this activity is associated with pheophytins a and b. © 2000 Society of Chemical Industry 相似文献
997.
Jung‐Hwa Choi Jin‐Won Kang A. T. M. Mijanur Rahman Seung Ju Lee 《Journal of the Institute of Brewing》2016,122(1):143-146
High‐pressure treatment, which is an effective means of enhancing enzymatic reactions, was implemented during beer mashing to increase the production yield of fermentable sugar (FS). The malt solution was heated (62, 67, and 72°C) under pressure [0.1 (1 atm), 2, 50 and 100 MPa], and the FS was measured. The amount of FS reached an equilibrium level, which was the highest at 67°C and at 2 MPa. The pressures were 2, 50, 100, and 0.1 MPa in decreasing order of FS amount at 67°C. The temperatures were 67, 72 and 62°C in decreasing order of FS amount at 2 MPa. With a mechanistic approach, only the effect of pressure on gelatinization was analysed. The gelatinization degrees were also higher at pressures higher than 0.1 MPa. This observation highlights the positive effect (increasing the FS yield) of high‐pressure treatment on beer mashing. Copyright © 2015 The Institute of Brewing & Distilling 相似文献
998.
Determination of a kinetic factor influencing the vaporescence of flavour components from wort 下载免费PDF全文
Hans Scheuren Frank Schuster Robert Koukol Karl Sommer Frank‐Jürgen Methner Michael Dillenburger 《Journal of the Institute of Brewing》2016,122(2):310-316
The current article considers the question of whether vaporescence during wort boiling affects evaporation via the vapour side mass transport. Thereby the vaporization of unwanted flavour components (such as dimethyl sulphide or benzaldehyde) can be influenced negatively or positively, which affects the amount of energy needed. The question is pursued by pre‐calculation and experimental validation of the vapour side mass stream at the evaporation surface: for that purpose vaporescence trials were carried out in a plant trial, with both benzaldehyde and water as pure substances and a mixture of benzaldehyde and water in an infinite solution (xi < 10?6). Trial parameters were process temperature and volume stream of the gas phase. The results obtained by the trials with pure substances enable pre‐calculation of vapour side mass transport. Then, pre‐calculation is compared with the results of the mixture trials and thus verified. As a result it has to be stated that vaporescence in the brew houses is pre‐calculable and that the mass transport has an impact on the vaporescence at the vapour side boundary layer. Copyright © 2016 The Institute of Brewing & Distilling 相似文献
999.
The impact of maturation on concentrations of key odour active compounds which determine the aroma of tequila 下载免费PDF全文
Ivonne Wendolyne González‐Robles David J. Cook 《Journal of the Institute of Brewing》2016,122(3):369-380
Samples of non‐mature and añejo (matured) tequila of the same brand/provenance were analysed using GC–MS and gas chromatography olfactometry (GC‐O)/aroma extract dilution analysis (AEDA) to provide quantitative data on the most odour active compounds that contribute to the aroma of these spirits. Extracts of non‐mature tequila were characterized by 26 odour‐active regions, which included ethyl hexanoate, ethyl octanoate, 2‐phenylethyl acetate, β‐damascenone, isoamyl alcohol and octanoic acid as the most odour‐active compounds (flavour dilution, FD, factor ≥ 6561). In contrast, extracts of the mature spirit showed 36 odour‐active zones, where the compounds with the highest FD factors (6561) were ethyl hexanoate, ethyl octanoate, 2‐phenylethyl acetate, isoamyl alcohol, phenethyl alcohol, guaiacol, 4‐ethyl guaiacol, vanillin, cis/trans whisky lactones, β‐damascenone and octanoic acid. The aromagram of mature tequila was thus differentiated from that of the non‐mature spirit owing to the presence of cask‐extractive compounds and the increased FD factors of certain terpenes, higher alcohols and acetals. This study provides a comprehensive and quantitative understanding of changes in key odourants of tequila as a result of the maturation process and also reveals a further characterization of the likely impact of each compound on overall spirit flavour, in terms of odour activity values. Copyright © 2016 The Institute of Brewing & Distilling 相似文献
1000.
Influence of yeast on the yield of fermentation and volatile profile of ‘Węgierka Zwykła’ plum distillates 下载免费PDF全文
Katarzyna Pielech‐Przybylska Maria Balcerek Agnieszka Nowak Piotr Patelski Urszula Dziekońska‐Kubczak 《Journal of the Institute of Brewing》2016,122(4):612-623
The character of plum brandies depends on a unique aroma profile of the plum and the microbiota present on the surface of the fruits, as well as yeast used for fermentation. In this study, an evaluation of the effect of microorganisms applied for the fermentation of W?gierka Zwyk?a var. plum mashes and processing temperature (18 °C, 30 °C) on its efficiency and volatile profile, as well as taste and flavour of distillates obtained was performed. An estimation of the odour activity values (OAVs) of the volatile compounds was also conducted. Regardless of whether the fermentation was carried out using Saccharomyces bayanus wine yeast or by native microflora present on plums as well as raisins, the efficiency of this process was high and ranged between 91.7 and 96.7% of the theoretical efficiency. Especially rich in esters (among others ethyl acetate and isoamyl acetate) was the distillate derived after fermentation with the microflora of plums and raisins, at 18 °C. An evaluation of the individual aromatic effect of chemical compounds present in tested distillates, in terms of their OAVs, revealed that the highest OAVs were reached with isovaleraldehyde. Other compounds that showed aroma values >1 and possibly had an effect on the overall aroma of tested plum distillates were the following: hexanal, benzaldehyde, ethyl acetate, isoamyl acetate, ethyl benzoate, ethyl hexanoate, 1‐propanol, 2‐methyl‐1‐butanol, 3‐methyl‐1‐butanol and 1‐hexanol. The performed sensory ranking showed that the best rated distillate was the one obtained after fermentation with the indigenous microflora of plums and raisins, at 18 °C. Copyright © 2016 The Institute of Brewing & Distilling 相似文献