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41.
Identification of Aminoimidazole and Aminothiazole Derivatives as Src Family Kinase Inhibitors
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Dr. Cinzia Maria Francini Dr. Anna Lucia Fallacara Dr. Roberto Artusi Dr. Laura Mennuni Dr. Alessia Calgani Dr. Adriano Angelucci Prof. Silvia Schenone Prof. Maurizio Botta 《ChemMedChem》2015,10(12):2027-2041
Src family kinases (SFKs) are a family of non‐receptor tyrosine kinases (TKs) implicated in the regulation of many cellular processes. The aberrant activity of these TKs has been associated with the growth and progression of cancer. In particular, c‐Src is overexpressed or hyperactivated in a variety of solid tumors and is most likely a strong promoting factor for the development of metastasis. Herein, the synthesis of new 4‐aminoimidazole and 2‐aminothiazole derivatives and their in vitro biological evaluation are described for their potential use as SFK inhibitors. Initially, 2‐aminothiazole analogues of dasatinib and 4‐aminoimidazole derivatives were synthesized and tested against the SFKs Src, Fyn, Lyn, and Yes. Five hits were identified as the most promising compounds, with Ki values in the range of 90–480 nm . A combination of molecular docking, homology modeling, and molecular dynamics were then used to investigate the possible binding mode of such compounds within the ATP binding site of the SFKs. Finally, the antiproliferative activities of the best candidates were evaluated against SH‐SY5Y and K562 cell lines. Compound 3 b [2‐(4‐{2‐methyl‐6‐[(5‐phenylthiazol‐2‐yl)amino]pyrimidin‐4‐yl}piperazin‐1‐yl)ethanol] was found to be the most active inhibitor. 相似文献
42.
Adriano Sofo Antonio Scopa Maria Nuzzaci Antonella Vitti 《International journal of molecular sciences》2015,16(6):13561-13578
Hydrogen peroxide (H2O2), an important relatively stable non-radical reactive oxygen species (ROS) is produced by normal aerobic metabolism in plants. At low concentrations, H2O2 acts as a signal molecule involved in the regulation of specific biological/physiological processes (photosynthetic functions, cell cycle, growth and development, plant responses to biotic and abiotic stresses). Oxidative stress and eventual cell death in plants can be caused by excess H2O2 accumulation. Since stress factors provoke enhanced production of H2O2 in plants, severe damage to biomolecules can be possible due to elevated and non-metabolized cellular H2O2. Plants are endowed with H2O2-metabolizing enzymes such as catalases (CAT), ascorbate peroxidases (APX), some peroxiredoxins, glutathione/thioredoxin peroxidases, and glutathione sulfo-transferases. However, the most notably distinguished enzymes are CAT and APX since the former mainly occurs in peroxisomes and does not require a reductant for catalyzing a dismutation reaction. In particular, APX has a higher affinity for H2O2 and reduces it to H2O in chloroplasts, cytosol, mitochondria and peroxisomes, as well as in the apoplastic space, utilizing ascorbate as specific electron donor. Based on recent reports, this review highlights the role of H2O2 in plants experiencing water deficit and salinity and synthesizes major outcomes of studies on CAT and APX activity and genetic regulation in drought- and salt-stressed plants. 相似文献
43.
Anthocyanin composition and extractability in berry skin and wine of Vitis vinifera L. cv. Aglianico
Manfra M De Nisco M Bolognese A Nuzzo V Sofo A Scopa A Santi L Tenore GC Novellino E 《Journal of the science of food and agriculture》2011,91(15):2749-2755
BACKGROUND: The present article reports the anthocyanin content in the berry skin and wine of the Italian red grape cultivar Aglianico (clone VCR11 grafted onto 1103 Paulsen), one of the most ancient vines and famous for its deep‐red colour. Anthocyanins were extracted from frozen berry skin in an acidified methanol solution. The extraction mixtures, monitored for 120 h, were analysed by high‐performance liquid chromatography. RESULTS: The extraction from berry skin of delphinidin, petunidin and malvidin appeared to be a time‐independent process, whereas the concentration of peonidin increased linearly with time. Peonidin‐O‐acetyl‐glucoside was transferred from skin more slowly than petunidin‐O‐acetyl‐glucoside and malvidin‐O‐acetyl‐glucoside. The anthocyanin composition of the resulting wine showed that the total anthocyanin content was about one‐tenth of the corresponding berry skin content. The ratio acetyl/coumaroyl anthocyanins in the wine was sharply higher than the value in berry skin (0.85 and 0.10, respectively), indicating an enrichment of acetyl derivatives in the wine. CONCLUSION: Levels of single anthocyanins in wine were not always correlated with those detected in grapes, as they were affected by winemaking. The high values of some anthocyanins in Aglianico wine could ameliorate its quality, increasing the chromatic properties, aging stability and product acceptance. Copyright © 2011 Society of Chemical Industry 相似文献
44.
Alberto Gomes Vieira de Carvalho Neto Thiago Amaral Ganzerli Adriano Luciano Cardozo Silvia Luciana Fávaro Antonio Guilherme Basso Pereira Emerson Marcelo Girotto Eduardo Radovanovic 《Polymer Composites》2014,35(4):768-774
In this work, sugarcane bagasse fibers were used as filler in composites having recycled high‐density polyethylene (PEr) as matrix. Because of the poor interaction between fibers surface and the PEr, the surface of bagasse was chemically modified. This modification consists of washing with water at 80°C, a mercerization process using sodium hydroxide and acetylation reaction with acetic anhydride. The chemical modification was characterized by Fourier transform infrared–horizontal attenuated total reflectance (FTIR‐HATR) and 13C nuclear magnetic resonance spectroscopies (NMR), thermogravimetric analysis (TGA), and scanning electronic microscopy (SEM). The composites were prepared from modified and unmodified fibers into PEr matrix, containing 5, 10, and 20% (w/w) of fiber. The samples were processed by extrusion and molds were prepared by injection process in order to perform mechanical tests. These materials were analyzed by SEM, TGA, and the water uptake was evaluated. Also, their mechanical properties were analyzed. Morphological analysis indicated that the chemical modification of sugarcane bagasse increased the compatibility between matrix and reinforcement. Tensile, flexural, and impact tests showed that the mechanical properties of the composite were improved compared to PEr due to the presence of the fibers. POLYM. COMPOS., 35:768–774, 2014. © 2013 Society of Plastics Engineers 相似文献
45.
Adriano Fagali de Souza Anselmo Eduardo Diniz Alessandro Roger Rodrigues Reginaldo Teixeira Coelho 《The International Journal of Advanced Manufacturing Technology》2014,71(9-12):1565-1577
This paper presents an investigation of nonplanar tool-workpiece interactions in free-form milling using a ball-end cutting tool, a technique that is widely applied in the manufacturing of dies and molds. The influence of the cutting speed on the cutting forces, surface quality of the workpiece, and chip formation was evaluated by considering the specific alterations of the contact between tool-surface along the cutting time. A trigonometric equation was developed for identifying the tool-workpiece contact along the toolpath and the point where the tool tip leaves the contact with the workpiece. The experimental validation was carried out in a machining center using a carbide ball-end cutting tool and a workpiece of AISI P20 steel. The experimental results demonstrated the negative effect of the engagement of the tool tip into the cut on machining performance. The length of this engagement depends on the tool and workpiece curvature radii and stock material. When the tool tip center is in the cut region, the material is removed by shearing together with plastic deformation. Such conditions increase the cutting force and surface roughness and lead to an unstable machining process, what was also confirmed by the chips collected. 相似文献
46.
In this paper, three different processes for puree extraction from Golden Delicious apples and enzyme inactivation are analyzed and compared: (i) hot extraction technique, (ii) cold extraction technique and (iii) a newly developed vacuum puree extraction technology (Zenith Chrono®). The analysis was carried out by means of manual laboratory operations reproducing the three processes. The primary objective of this study was the evaluation of the minimum amount of ascorbic acid that must be added to the three fruit purees in order to contain oxidization and color change in the products. Afterwards, the residual enzymatic activity was checked and characteristics of the products were compared (i.e. fraction of dried solids and consistency of the puree). All of the processes achieved complete enzyme deactivation and an imperceptible color change, and the results of this paper support interest in vacuum puree extraction technology. 相似文献
47.
We propose a new hub location model defined by the minimization of costs. The main contribution of this work is to permit the analysis of a hub-and-spoke network operated under “decentralized management”. In this type of network, various transport companies act independently, and each makes its route choices according to its own criteria, which can include cost, time, frequency, security and other factors, including subjective ones. Therefore, due to the diversity of the various companies’ criteria, one can expect that between each origin–destination pair, a fraction of the flow will be carried through hubs and a fraction will be carried by the direct route. to resolve this problem, it becomes necessary to determine the probability that any network user will choose the hub route for each trip to be made (or for each load to be carried). We present an integer programming formulation, subject the new model to experiments with an intermodal general cargo network in Brazil and address questions regarding the solution of the problem in practice. 相似文献
48.
49.
Adriano da Silva Éliton Fontana Viviana Cocco Mariani Francisco Marcondes 《International Journal of Heat and Mass Transfer》2012,55(23-24):6808-6818
Natural convection in trapezoidal cavities, especially those with two internal baffles in conjunction with an insulated floor, inclined top surface, and isothermal left-heated and isothermal right-cooled vertical walls, has been investigated numerically using the Element based Finite Volume Method (EbFVM). In numerical simulations, the effect of three inclination angles of the upper surface as well as the effect of the Rayleigh number (Ra), the Prandtl number (Pr), and the baffle’s height (Hb) on the stream functions, temperature profiles, and local and average Nusselt numbers has been investigated. A parametric study was performed for a wide range of Ra numbers (103 ? Ra ? 106) Hb heights (Hb = H1/3, 2H1/3, and H1), Pr numbers (Pr = 0.7, 10 and 130), and top angle (θ) ranges from 10 to 20. A correlation for the average Nusselt number in terms of Pr and Ra numbers, and the inclination of the upper surface of the cavity is proposed for each baffle height investigated. 相似文献
50.
João Fhilype Andrade Souto‐Maior Adriano Valim Reis Liliane Neves Pedreiro Osvaldo Albuquerque Cavalcanti 《Polymer International》2010,59(1):127-135
Pectin was chemically modified with different amounts of trisodium trimetaphosphate (STMP) in aqueous solution (pH = 12), thereby giving a material with reduced water solubility. The physiochemical characterization of this new material was carried out through Fourier transform infrared and thermogravimetric analyses. Phosphated pectin (Pect‐STMP) together with prebiotic (oligosaccharide) were incorporated into an aqueous dispersion of polymethacrylate (Eudragit® RS 30 D) in order to obtain free films using a casting process (50 °C) on a Teflon plate. The free films were evaluated using water vapour transmission, average swelling index in simulated gastric fluid (SGF) and simulated intestinal fluid, scanning electron microscopy and a diffusion study with theophylline in buffer solution with and without pectinolytic enzyme. The results suggest that the new material can be used in the coating process for oral solid‐reservoir systems, to prevent the premature release of drugs in SGF (pH = 1.2). Furthermore, the presence of both Pect‐STMP and oligosaccharide favours the specific degradation of the pellicle by the action of the enzymes produced by colonic microflora. The material obtained in this work has the potential to be applied in devices for drug delivery in the colon, making possible modified release of drugs. Nevertheless, subsequent colon‐specific experiments in vivo need to be carried out in order to confirm the possible application of this new material. Copyright © 2009 Society of Chemical Industry 相似文献