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71.
72.
Manoela Klüppel Riekes Monika Piazzon Tagliari Andrea Granada Gislaine Kuminek Marcos Antonio Segatto Silva Hellen Karine Stulzer 《Materials science & engineering. C, Materials for biological applications》2010,30(7):1008-1013
The aim of this work was to investigate the inclusion complexation between amiodarone (AMD), a practically water insoluble anti arrhythmic agent, and β-cyclodextrin (βCD) in order to improve the solubility and the dissolution rate of the drug, in an attempt to enhance its bioavailability. The complexation was done through different methods: physical mixture (PM), coevaporated (CV), freeze-drying (FD) and spray-drying (SD). The data analysis indicated that the complexes produced by freeze-drying and spray-drying techniques resulted in amorphous samples (data obtained by DSC and XRPD), and showed a possible chemical interaction between OH-βCD group and AMD tertiary amine (visualized by FT-IR). Also, they presented higher thermal stability (demonstrated by TG) and the improvement of the drug dissolution rate. 相似文献
73.
Manoela Klüppel Riekes Fernanda Malaquias Barboza Débora Dalla Vecchia Milton Bohatch Paulo Vitor Farago Daniel Fernandes Marcos Antonio Segatto Silva Hellen Karine Stulzer 《Materials science & engineering. C, Materials for biological applications》2011,31(5):962-968
Polymeric microparticles containing carvedilol (CRV) were obtained successfully using a simple emulsion/organic evaporating method. Three different formulations were developed using poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) and polycaprolactone (PCL) as polymers; the resulting samples were submitted to physical–chemical characterization and in vivo evaluation. The physical–chemical analysis indicated that the PHBV promoted a porous aspect in the microparticle's surface, while PCL a smooth aspect. The PCL-CRV microparticles showed a higher loading efficiency and a longer drug release time, being selected for in vivo evaluation. The in vivo assays indicated that PCL-CRV polymeric microparticles has a pharmacological antihypertensive effect for a longer period of time, representing a good alternative to improved the life quality of the patient that uses this drug. 相似文献
74.
This paper presents a new approach for GT part family and machine cell formation. It involves the integrated use of two fuzzy clustering algorithms: fuzzy c-means and fuzzy k-nearest neighbours. It is shown that the proposed approach performs better than using fuzzy c-means alone or FACT (Kamal and Burke) in terms of some commonly used measures such as grouping efficacy, grouping index, number of voids, number of exceptional elements, and number of bottleneck machines. The approach is developed a result of our quest for a better clustering algorithm to process non-binary data and to produce a non-binary classification in the domain of GT applications. These features are deemed important to handle imprecise data and to provide a higher degree of flexibility in the operation stage. 相似文献
75.
Pelletier Luc G.; Lavergne Karine J.; Sharp Elizabeth C. 《Canadian Metallurgical Quarterly》2008,49(4):304
This article emphasises the importance of psychology for the study and mitigation of sustainability issues. Over the past 20 years, a number of special issues on human behaviour and the environment have emerged in the literature, characterising the breadth of environmental problems and their consequences for our quality of life. The articles in this special section focus on psychology's role in interdisciplinary approaches to sustainability, with special attention given to the interdependency of environmental and human health. In this article, the authors summarise the main points of each of these contributions. In addition, they suggest tangible ways in which psychologists can meaningfully contribute to the environmental cause as individuals, practitioners, teachers, researchers, and administrators. Finally, the authors highlight future directions for research and practice in environmental psychology. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
76.
Transmission electron microscopy (TEM) observations show that dislocation channel deformation occurs in pre-irradiated austenitic stainless steels, even at low stress levels (∼175 MPa, 290 °C) in low neutron dose (∼0.16 dpa, 185 °C) material. The TEM observations are utilized to design finite element (FE) meshes that include one or two “soft” channels (i.e. low critical resolved shear stress (CRSS)) of particular aspect ratio (length divided by thickness) embedded at the free surface of a “hard” matrix (i.e. high CRSS). The CRSS are adjusted using experimental data and physically based models from the literature. For doses leading to hardening saturation, the computed surface slips are as high as 100% for an applied stress close to the yield stress, when the observed channel aspect ratio is used. Surface slips are much higher than the grain boundary slips because of matrix constraint effect. The matrix CRSS and the channel aspect ratio are the most influential model parameters. Predictions based on an analytical formula are compared with surface slips computed by the FE method. Predicted slips, either in surface or bulk channels, agree reasonably well with either atomic force microscopy measures reported in the literature or measures based on our TEM observations. Finally, it is shown that the induced surface slip and grain boundary stress concentrations strongly enhance the kinetics of the damage mechanisms possibly involved in IASCC. 相似文献
77.
Jihong Yang Zhongli Pan Gary Takeoka Bruce Mackey Gokhan Bingol Maria T. Brandl Karine Garcin Tara H. McHugh Hua Wang 《Food chemistry》2013
Infrared heating was recently used to develop a more efficient roasting technology than traditional hot air roasting. Therefore, in this study, we evaluated the shelf-life of almonds roasted with three different approaches, namely infrared (IR), sequential infrared and hot air (SIRHA) and regular hot air (HA). Nine medium roasted almond samples produced by the aforementioned heating methods were processed at three different temperatures (130, 140 and 150 °C), packed in paper bags and then stored at 37 °C for three, six or eight months. Shelf-life of the roasted almonds was determined by measuring the changes in colour, peroxide value, moisture content, water activity, volatile components and sensory quality. No significant difference was observed in moisture content and water activity among the almond samples processed with different roasting methods and stored under the same conditions. GC/MS analysis showed that aldehydes, alcohols, and pyrazines were the main volatile components of almonds. Aliphatic aldehydes such as hexanal, (E)-2-octenal, and nonanal were produced as off-odours during storage. Although the overall quality of roasted almonds produced with SIRHA and HA heating was similar during the first three months of storage, their peroxide value and concentration of aliphatic aldehydes differed significantly for different roasting methods and increased significantly in all roasted samples during storage. We postulate that hexanal and nonanal might be better indicators of the shelf life of roasted almonds than the current standard, peroxide value. 相似文献
78.
Syntheses,characterization, and hydrolytic degradation of P(ε‐caprolactone‐co‐δ‐valerolactone) copolymers: Influence of molecular weight 下载免费PDF全文
Biodegradable poly(ε‐caprolactone‐co‐δ‐valerolactone) copolymers were synthesized and investigated to study their behavior in aqueous medium. The copolyesters were produced by ring opening polymerization between ε‐caprolactone (CL) and δ‐valerolactone (VL) in bulk at 140°C using tin(II) octoate as catalyst. They were characterized by using 1H NMR, size exclusion chromatography, differential scanning calorimetry, and MALDI TOF mass spectrometry. Reactivity ratio determination gave an insight on their microstructure. Hydration, hydrolytic degradation, and biocide release of P(CL‐VL) films with different molecular weights values were studied. A one‐order kinetic whose rate constant decreases with copolymer macromolecular weight was observed. Although the molecular weight decrease remained relatively weak after 8 months of immersion, a correlation between molecular weight and hydrolysis rate was shown by high performance liquid chromatography‐mass spectrometry. The ability of the P(CL‐VL) films to release active compounds dispersed in the films was studied by atomic absorption spectroscopy. The release behavior of all copolymers was identical with a zero‐order kinetic. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43007. 相似文献
79.
Blanc F Vissers YM Adel-Patient K Rigby NM Mackie AR Gunning AP Wellner NK Skov PS Przybylski-Nicaise L Ballmer-Weber B Zuidmeer-Jongejan L Szépfalusi Z Ruinemans-Koerts J Jansen AP Bernard H Wal JM Savelkoul HF Wichers HJ Mills EN 《Molecular nutrition & food research》2011,55(12):1887-1894
Scope : Roasting rather than boiling and Maillard modifications may modulate peanut allergenicity. We investigated how these factors affect the allergenic properties of a major peanut allergen, Ara h 1. Methods and results : Ara h 1 was purified from either raw (N‐Ara h 1) or roasted (R‐Ara h 1) peanuts. Boiling (100°C 15 min; H‐Ara h 1) resulted in a partial loss of Ara h 1 secondary structure and formation of rod‐like branched aggregates with reduced IgE‐binding capacity and impaired ability to induce mediator release. Glycated Ara h 1 (G‐Ara h 1) formed by boiling in the presence of glucose behaved similarly. However, H‐ and G‐Ara h1 retained the T‐cell reactivity of N‐Ara h 1. R‐Ara h 1 was denatured, comprised compact, globular aggregates, and showed no evidence of glycation but retained the IgE‐binding capacity of the native protein. Conclusion : Ara h 1 aggregates formed by boiling were morphologically distinct from those formed by roasting and had lower allergenic activity. Glycation had no additional effect on Ara h 1 allergenicity compared with heating alone. Taken together with published data on the loss of Ara h 2/6 from boiled peanuts, this supports the hypothesis that boiling reduces the allergenicity of peanuts. 相似文献
80.
The electrochemical reduction of flavin adenine dinucleotide (FAD) is studied in a classical electrochemical cell as well as in two types of microreactors: the first one is a one-channel reactor and the other one, a multichannel filter-press reactor. The ultimate goal is to use the reduced form of flavin (FADH2), in the presence of formate dehydrogenase (FDH), in order to continuously regenerate the reduced form of nicotinamide adenine dinucleotide (NADH) for chiral syntheses. Various voltammetric and adsorption measurements were carried out for a better understanding of the redox behavior of the FAD as well as its adsorption on gold. Diffusivity and kinetic electrochemical parameters of FAD were determined. 相似文献