全文获取类型
收费全文 | 1580篇 |
免费 | 134篇 |
国内免费 | 5篇 |
专业分类
电工技术 | 3篇 |
综合类 | 2篇 |
化学工业 | 143篇 |
金属工艺 | 4篇 |
机械仪表 | 20篇 |
建筑科学 | 6篇 |
矿业工程 | 1篇 |
能源动力 | 21篇 |
轻工业 | 1193篇 |
水利工程 | 6篇 |
石油天然气 | 223篇 |
无线电 | 3篇 |
一般工业技术 | 57篇 |
冶金工业 | 6篇 |
原子能技术 | 3篇 |
自动化技术 | 28篇 |
出版年
2024年 | 32篇 |
2023年 | 55篇 |
2022年 | 109篇 |
2021年 | 108篇 |
2020年 | 138篇 |
2019年 | 93篇 |
2018年 | 84篇 |
2017年 | 89篇 |
2016年 | 100篇 |
2015年 | 91篇 |
2014年 | 123篇 |
2013年 | 90篇 |
2012年 | 95篇 |
2011年 | 94篇 |
2010年 | 59篇 |
2009年 | 41篇 |
2008年 | 19篇 |
2007年 | 42篇 |
2006年 | 35篇 |
2005年 | 36篇 |
2004年 | 7篇 |
2003年 | 18篇 |
2002年 | 24篇 |
2001年 | 24篇 |
2000年 | 16篇 |
1999年 | 16篇 |
1998年 | 13篇 |
1997年 | 3篇 |
1996年 | 4篇 |
1995年 | 3篇 |
1994年 | 4篇 |
1993年 | 13篇 |
1992年 | 6篇 |
1991年 | 6篇 |
1990年 | 2篇 |
1989年 | 1篇 |
1988年 | 5篇 |
1987年 | 7篇 |
1986年 | 13篇 |
1982年 | 1篇 |
排序方式: 共有1719条查询结果,搜索用时 109 毫秒
1.
Peng Wang Yan Li Yujiao Qu Baowei Wang Jingxin Sun Chunwei Miao Ming Huang He Huang Congxiang Zhang 《International Journal of Food Science & Technology》2022,57(6):3428-3439
The effects of cellulose microfibres (CMFs, Average size: 100 ± 5 μm) and cellulose nanofibres (CNFs, Average size: 60 ± 3 nm) on the properties of myofibrillar protein (MP) gels from duck breast meat were studied. The results demonstrated that CMFs and CNFs were mostly connected to MP by non-covalent bonds, the diffusion and cross-linking of MP molecules was promoted, and a denser and more complete gel network was formed. With the increases of CMFs and CNFs concentration (0–10%), the hardness was increased by 13.15% and 19.78% for CMFs10% and CNFs10% gels, respectively, and the elasticity was increased by 40% and 80%, respectively. At the same concentration (0–10%), the increase in gel hardness, viscoelasticity and immobilised water content was greater in the CNFs-MP group than in the CMFs-MP group. The CNFs-MP group had a tighter gel network, and CNFs had a better potential to improve the gelation performance of MP. 相似文献
2.
Effects of different carbon sources and C/N values on nonvolatile taste components of Pleurotus eryngii
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)
Wen Li Xiaobei Li Yan Yang Feng Zhou Yanfang Liu Shuai Zhou Hailong Yu 《International Journal of Food Science & Technology》2015,50(11):2360-2366
Pleurotus eryngii, the second largest industrial cultivation mushroom in China, is usually cultivated on substrates mainly consisting of sawdust and corncob. In this study, experiments were performed to determine the effects of different carbon sources and C/N values on nonvolatile taste components of P. eryngii. The effects of different carbon sources on nonvolatile taste components levels revealed that sawdust was beneficial to high levels of crude protein, amino acids, 5′‐nucleotides and equivalent umami concentration, while corncob was beneficial to high contents of carbohydrate, polysaccharides and trehalose. At the similar C/N values, relatively higher sawdust content was beneficial to umami amino acid production, while relatively higher corncob content was beneficial to high contents of carbohydrate, polysaccharides and mannitol. Higher C/N value was beneficial to high levels of crude protein, amino acids, 5′‐nucleotides and equivalent umami concentration, while lower C/N value was beneficial to high contents of carbohydrate, polysaccharides and trehalose. These results provided information for P. eryngii fruit body industrial cultivation to obtain specific nonvolatile taste components with high levels. 相似文献
3.
Coffee melanoidins have attracted interest as a result of its potential health benefits. This investigation aims to elucidate the extraction behavior of melanoidins and their populations during the preparation of portioned espresso coffee and its relationship with the antioxidant activity of the coffee brew. Filter-paper pods, FAP capsule, and clone capsule containing light roasted coffee have been investigated. An accumulative fractionation approach has applied to model the extraction kinetics of melanoidins, melanoidin populations, browning, chlorogenic acids (CGA), and antioxidant activity. Melanoidins were very efficiently extracted in clone capsules since less than 9 s was necessary to extract the 50% of the melanoidin content as compared with pods and FAP capsules, and the kinetic of extraction is slower than CGA. The extraction profile of melanoidins and browning fitted better with the antioxidant capacity than CGA and total solids profile. Melanoidin populations were obtained according to ethanol solubility. Total melanoidin content and the ratio between melanoidin populations did not change during extraction volume for espresso coffee. Melanoidin populations soluble at 75% ethanol showed the highest antioxidant activity. However, melanoidins with higher antioxidant activity are extracted at higher volumes. This investigation could make possible the adjustment of the technological requirements of espresso coffeemakers to produce an espresso coffee with high levels of beneficial compounds. 相似文献
4.
Iron–peptide complexes have been considered a promising source of more bioavailable iron, with reduced side effects as compared to iron salts. Whey protein isolate (WPI) hydrolyzed by alcalase, pancreatin or flavourzyme was ultrafiltered (cut off 5 kDa) and their fractions – retentates and filtrates – were evaluated for iron-binding capacity. The Fe–hydrolysate complexation reaction resulted in a dramatic increase in iron solubility at pH 7.0, from 0% to almost 100%. This result was obtained regardless of the molecular mass profile or the enzyme used to obtain the samples. Fractions from hydrolysate obtained with pancreatin (HP) were chosen to continue the study. The complexes formed with both fractions from HP were stable under simulated gastric digestion (50.8–89.4%). To identify the peptides with iron-binding capacity, the HP fractions were isolated by IMAC-Fe3 +, and the retentate showed higher relative concentrations of iron-binding peptides than the filtrate. Iron-binding peptide sequencing, accomplished by LC–MS/MS, showed Glu and/or Asp in all the sequences, and their carboxylic groups were amongst the main iron-binding sites. WPI hydrolysis with pancreatin yields peptides that can form iron complexes with the potential to increase iron bioavailability and reduce its pro-oxidant effect. 相似文献
5.
6.
7.
《Food Control》2006,17(2):93-101
This paper presents the efforts of the Bureau of Quarantine and International Health Surveillance (BQIHS), Department of Health (DOH), Philippines to launch a Good Manufacturing Procedure (GMP)–Hazard Analysis Critical Control Point (HACCP) Certification Program for food services operating in Philippine inter-island water vessels. The BQIHS improved its food sanitation audit system for inter-island ships by including in its traditional walk-through evaluation of GMP the review of documents for both GMP and HACCP, and the verification of HACCP implementation. The BQIHS is now identified as a GMP–HACCP certification provider to specific sectors of the local food service industry on a national level. 相似文献
8.
《Catalysis communications》2007,8(11):1834-1837
Benzophenone and its derivatives were prepared via Friedel–Crafts acylation reactions using ionic liquids (ILs) of BmimCl–FeCl3, BmimCl–AlCl3 and BmimCl–ZnCl2 as dual catalyst–solvent. Among them, BmimCl–FeCl3 showed much higher catalytic activity than that observed for the other two ILs, and in conventional organic solvents. In these reaction systems, good to excellent yields (up to 97%) of acylation products were obtained in a short reaction time. This method features high yield, a simple product isolation procedure, ILs reusability and reduced waste discharge, thus rendering this catalytic system both efficient and environmentally friendly. 相似文献
9.
Selection of strategies that help reduce riverine inputs requires numerical models that accurately quantify hydrologic processes. While numerous models exist, information on how to evaluate and select the most robust models is limited. Toward this end, we developed a comprehensive approach that helps evaluate watershed models in their ability to simulate flow regimes critical to downstream ecosystem services. We demonstrated the method using the Soil and Water Assessment Tool (SWAT), the Hydrological Simulation Program–FORTRAN (HSPF) model, and Distributed Large Basin Runoff Model (DLBRM) applied to the Maumee River Basin (USA). The approach helped in identifying that each model simulated flows within acceptable ranges. However, each was limited in its ability to simulate flows triggered by extreme weather events, owing to algorithms not being optimized for such events and mismatched physiographic watershed conditions. Ultimately, we found HSPF to best predict river flow, whereas SWAT offered the most flexibility for evaluating agricultural management practices. 相似文献
10.
The effect of the N-linked glycans on structural features and physicochemical functions of soybean β-conglycinin homotrimers 总被引:2,自引:0,他引:2
Nobuyuki Maruyama Mohamad Ramlan Mohamed Salleh Koji Takahashi Kazuhiro Yagasaki Hideyuki Goto Naho Hontani Shuko Nakagawa Shigeru Utsumi 《Journal of the American Oil Chemists' Society》2002,79(2):139-144
β-Conglycinin is a trimeric protein consisting of three subunits, α,α′,and β, which are N-glycosylated. The α and α′ subunits
contain extension regions in addition to core regions common to all subunits. We purified homogeneous trimers consisting of
only α, α′, or β from mutant soybean cultivars containing β-conglycinin lacking one or two subunits: α homotrimers from an
α′-lacking mutant, α′ homotrimers from an α-lacking mutant, and β homotrimers from an α-and α′-lacking mutant. Structural
features and physicochemical functions of the three homotrimers were examined and compared with those of recombinant homotrimers
having no N-linked glycans. The native homotrimers have secondary structures very similar to those of the recombinant ones.
In analogy with the recombinant homotrimers, the native ones exhibit different thermal stabilities from one another (β>α′>α),
and the native α and α′ homotrimers exhibit better solubility, emulsifying ability, and heat-induced association than the
native β homotrimer. Further, the N-linked glycans contribute to solubilities of the three subunits at low ionic strength
(μ=0.08) and to the emulsifying ability of the native β homotrimer. N-Linked glycans also prevent heat-induced associations
of the native α and α′ homotrimers but do not contribute to the secondary structure and the thermal stability of β-conglycinin. 相似文献