全文获取类型
收费全文 | 130篇 |
免费 | 6篇 |
专业分类
电工技术 | 1篇 |
化学工业 | 29篇 |
金属工艺 | 2篇 |
建筑科学 | 3篇 |
轻工业 | 56篇 |
水利工程 | 1篇 |
石油天然气 | 1篇 |
一般工业技术 | 15篇 |
冶金工业 | 3篇 |
自动化技术 | 25篇 |
出版年
2024年 | 1篇 |
2023年 | 1篇 |
2022年 | 7篇 |
2021年 | 11篇 |
2020年 | 6篇 |
2019年 | 2篇 |
2018年 | 5篇 |
2017年 | 6篇 |
2016年 | 3篇 |
2015年 | 3篇 |
2014年 | 6篇 |
2013年 | 8篇 |
2012年 | 6篇 |
2011年 | 12篇 |
2010年 | 11篇 |
2009年 | 9篇 |
2008年 | 9篇 |
2007年 | 6篇 |
2006年 | 4篇 |
2005年 | 3篇 |
2004年 | 2篇 |
2003年 | 1篇 |
2002年 | 4篇 |
2001年 | 4篇 |
2000年 | 1篇 |
1999年 | 1篇 |
1997年 | 1篇 |
1996年 | 1篇 |
1992年 | 1篇 |
1968年 | 1篇 |
排序方式: 共有136条查询结果,搜索用时 15 毫秒
61.
Marina Martinez-Vargas Maribel Soto-Nu?ez Erika Tabla-Ramon Barbara Solis Ruben Gonzalez-Rivera Adan Perez-Arredondo Francisco Estrada-Rojo Andres Castell Juan Molina-Guarneros Luz Navarro 《International journal of molecular sciences》2014,15(4):5807-5820
Cathepsin B is one of the major lysosomal cysteine proteases involved in neuronal protein catabolism. This cathepsin is released after traumatic injury and increases neuronal death; however, release of cystatin C, a cathepsin inhibitor, appears to be a self-protective brain response. Here we describe the effect of cystatin C intracerebroventricular administration in rats prior to inducing a traumatic brain injury. We observed that cystatin C injection caused a dual response in post-traumatic brain injury recovery: higher doses (350 fmoles) increased bleeding and mortality, whereas lower doses (3.5 to 35 fmoles) decreased bleeding, neuronal damage and mortality. We also analyzed the expression of cathepsin B and cystatin C in the brains of control rats and of rats after a traumatic brain injury. Cathepsin B was detected in the brain stem, cerebellum, hippocampus and cerebral cortex of control rats. Cystatin C was localized to the choroid plexus, brain stem and cerebellum of control rats. Twenty-four hours after traumatic brain injury, we observed changes in both the expression and localization of both proteins in the cerebral cortex, hippocampus and brain stem. An early increase and intralysosomal expression of cystatin C after brain injury was associated with reduced neuronal damage. 相似文献
62.
Ana Patricia Martínez‐Camacho Mario Onofre Cortez‐Rocha María Mónica Castillo‐Ortega Armando Burgos‐Hernández Josafat Marina Ezquerra‐Brauer Maribel Plascencia‐Jatomea 《Polymer International》2011,60(12):1663-1669
Chitosan is a natural polymer with both antimicrobial activity and nanofiber‐forming capability. The electrospinning technique allows the production of chitosan nanofibers but still faces several problems such as the small number of suitable solvents for the process and the large number of factors affecting quality and production of the nanofibers, among others. The antimicrobial properties of chitosan nanofibers have been little studied; therefore, the most probable mechanism of action and the effect of the conformation or arrangement of the molecules in the nanofibers remain unknown. The presence of residual solvent in the materials is one factor that has complicated the assessment of the antimicrobial activity of chitosan nanofibers. The research in this area will be very important for the future of these materials. Copyright © 2011 Society of Chemical Industry 相似文献
63.
Bernab L. Rivas S. Amalia Pooley Eduardo D. Pereira Rocío Cid Maribel Luna M. Antonieta Jara Kurt E. Geckeler 《应用聚合物科学杂志》2005,96(1):222-231
The commercial polymers poly(ethylene imine) (PEI), poly(ethylene imine epichlorohydrin), and poly(dimethylamine‐co‐epichlorohydrin) were purified and fractionated by ultrafiltration. Their metal‐ion‐binding properties with respect to different ligand groups and the effect of the concentration on the retention properties were investigated. The amine ligands of the polymers formed the most stable complexes with the metal ions. In general, there was an effect of the pH and polymer fraction size on the retention properties. As the pH and polymer fraction size increased, the affinity to bind metal ions also increased. PEI had the highest metal‐retention values, particularly at higher pHs, at which the amine groups were nonprotonated and could coordinate easily with the metal ions. Only Pb(II) was poorly retained. The affinity for all the metal ions, except Pb(II), increased significantly at pH 5. The metal‐ion retention decreased quickly as the filtration factor increased, except for Cu(II), Co(II), Ni(II), Cd(II), and Zn(II) ions, which were retained by over 40% at a filtration factor of 4. For other metal ions such as Pb(II), Ca(II), and Mg(II), only 10% remained bound to the polymer. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 96: 222–231, 2005 相似文献
64.
Elsa M. Arce-Estrada Victor M. Lopez-Hirata Lobsang Martinez-Lopez Hector J. Dorantes-Rosales Maribel L. Saucedo-Muń oz Felipe Hernández-Santiago 《Journal of Materials Science》2003,38(2):275-278
Mechanically alloyed Co-20wt%Ni-10wt%Mo and Co-70wt%Ni-10wt%Mo (nominal compositions) alloy powders were produced by milling of pure elemental powders. Mechanically alloyed powders were characterized by X-ray diffraction, scanning electron microscopy and transmission electron microscopy. MA powder specimens were tested electrollitically in a 30% KOH aqueous solution at 298 K. X-ray diffraction analysis and transmission electron microscopy of milled powders showed the presence of two phases, an fcc solid solution and intermetallic compounds of Ni or Co with Mo. These phases showed a nanometric size. The linear sweep voltammograms confirmed also the presence of two phases in both mechanically alloyed alloy powders. The Co-20wt%Ni-10wt%Mo alloy powders showed the best electrocatalytic activity for hydrogen evolution reaction. 相似文献
65.
Quintana-Ortí Enrique S. Quintana-Ortí Gregorio Castillo Maribel Hernández Vicente 《The Journal of supercomputing》2001,20(1):55-66
We investigate in this paper the performance of parallel algorithms for computing the controllable part of a control linear system, with application to the computation of minimal realizations. Our approach is based on a method that transforms the matrices of the system to block Hessenberg form by using rank-revealing orthogonal factorizations.The experimental analysis on a high performance architecture includes two rank-revealing numerical tools: the SVD and the rank-revealing QR factorizations. Results are also reported, using the rank-revealing QR factorizations, on a parallel distributed architecture. 相似文献
66.
Donado-Godoy P Clavijo V León M Tafur MA Gonzales S Hume M Alali W Walls I Lo Fo Wong DM Doyle MP 《Journal of food protection》2012,75(6):1134-1138
A cross-sectional study was performed to estimate the prevalence of Salmonella on retail market chicken carcasses in Colombia. A total of 1,003 broiler chicken carcasses from 23 departments (one city per department) were collected via a stratified sampling method. Carcass rinses were tested for the presence of Salmonella by conventional culture methods. Salmonella strains were isolated from 27 % of the carcasses sampled. Logistic regression analysis was used to determine potential risk factors for Salmonella contamination associated with the chicken production system (conventional versus free-range), storage condition (chilled versus frozen), retail store type (supermarket, independent, and wet market), poultry company (integrated company versus nonintegrated company), and socioeconomic stratum. Chickens from a nonintegrated poultry company were associated with a significantly (P < 0.05) greater risk of Salmonella contamination (odds ratio, 2.0) than were chickens from an integrated company. Chilled chickens had a significantly (P < 0.05) higher risk of Salmonella contamination (odds ratio, 4.3) than did frozen chicken carcasses. 相似文献
67.
68.
69.
70.
Freshness assessment of ray fish stored in ice by biochemical,chemical and physical methods 总被引:2,自引:0,他引:2
V.M. Ocaño-Higuera A.N. Maeda-Martínez E. Marquez-Ríos D.F. Canizales-Rodríguez F.J. Castillo-Yáñez E. Ruíz-Bustos A.Z. Graciano-Verdugo M. Plascencia-Jatomea 《Food chemistry》2011
Ray fish were caught, filleted, and stored in ice. Fillets were analysed for 18 days to determine the chemical, biochemical and physical changes and their relation to the muscle eating quality. Trimethylamine (TMA-N), total volatile bases (TVB-N), ATP content and breakdown products, K value, pH, texture, water-holding capacity (WHC) and colour changes were monitored. At the beginning of the study, the ray fish muscle showed a low concentration of ATP and a high value of inosine 5′-monophosphate (IMP). Regarding to the signs of freshness and deterioration, K value presented an exponential increase (r2 = 0.95) with an initial value of 4.7% and a final value of 47.5%. Furthermore, the TBV-N and TMA-N significantly increased (P < 0.05) during the storage in ice. As for the physical analysis whereas the texture changed (P < 0.05); pH and the WHC were not affected (P < 0.05). The overall results of this study indicated that the edible quality of ray fish muscle was maintained during at least 15 days of ice storage. 相似文献