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31.
Green projects: An information drives analysis of four cases 总被引:2,自引:0,他引:2
Richard T. Watson Marie-Claude Boudreau Adela J. Chen Hctor Hito Sepúlveda 《The Journal of Strategic Information Systems》2011,20(1):55-62
An analysis of four transportation systems (Vélib, Zipcar, ERP Singapore, and Transantiago) shows the strategic value of creating a symbiotic relationship between physical and informational systems in order to increase the convenience and patronage of these systems. The four information drives (ubiquity, uniqueness, unison, and universality) are extended to a physical setting and used to report the key characteristics of each system from both a physical and informational perspective. The article argues that the traditional customer orientation to determining systems requirements may fail to create the breakthrough systems designs that are required to reduce society’s climate harming emissions. Rather, we need an innovation orientation based on understanding consumers’ fundamental physical and informational needs. 相似文献
32.
Chemistry in confined conditions is explored at the level of the interlayer space of multiwall carbon nanotubes. Starting from preliminary intercalated tubes, a ligand exchange reaction has been successfully conducted within the former Van der Waals gap, resulting in a final dispersion of heteroatomic particles, around 2 nm large and nearly homogeneous in size, on the outer surface of the tubes. Intercalated tubular carbon architectures thus prove to be interesting templates for a bottom-up preparation of chemically complex supported nanoparticles, with potential activities for versatile applications. 相似文献
33.
Aurélien Desmarchelier Sébastien Anizan Mai Minh Tien Marie-Claude Savoy Cindy Bion 《Food additives & contaminants. Part A, Chemistry, analysis, control, exposure & risk assessment》2018,35(4):686-694
An LC-MS/MS method is presented for screening five tetracyclines and their epimers in a broad range of food products. The scope of matrices includes meat-, fish-, seafood-based products, various dairy ingredients, infant formulae and fats. The method principle is based on a liquid–liquid extraction with aqueous ethylenediaminetetraacetic acid (EDTA) and acetonitrile followed by a freezing step to promote phase separation at low temperature. After defatting with hexane, sample extracts were evaporated and reconstituted before injection onto the LC-MS/MS system. The addition of oxalic acid in the aqueous mobile phase was mandatory to maintain good peak shape and sensitivity over the run. The screening is based upon a double preparation of each sample, one ‘as such’ and a second one with the analytes spiked in the sample, in order to mitigate the risk of false negative response. The method was validated according to the European Community Reference Laboratories Residues Guidelines. A total of 93 samples were included in the validation by two independent laboratories giving both false-negative and false-positive rates at 0% for all compounds. Over the last two years, 2600 samples were analysed routinely and only one chicken sample was found above the regulatory limit. 相似文献
34.
Aurélien Desmarchelier Kaïli Fan Mai Minh Tien Marie-Claude Savoy Adrienne Tarres Denis Fuger 《Food additives & contaminants. Part A, Chemistry, analysis, control, exposure & risk assessment》2018,35(4):646-660
A procedure for screening 105 veterinary drugs in foods by liquid chromatography tandem mass-spectrometry (LC-MS/MS) is presented. Its scope encompasses raw materials of animal origin (milk, meat, fish, egg and fat) but also related processed ingredients and finished products commonly used and manufactured by food business operators. Due to the complexity of the matrices considered and to efficiently deal with losses during extraction and matrix effects during MS source ionisation, each sample was analysed twice, that is ‘unspiked’ and ‘spiked at the screening target concentration’ using a QuEChERS-like extraction. The entire procedure was validated according to the European Community Reference Laboratories Residues Guidelines. False-negative and false-positive rates were below 5% for all veterinary drugs whatever the food matrix. Effectiveness of the procedure was further demonstrated through participation to five proficiency tests and its ruggedness demonstrated in quality control operations by a second laboratory. 相似文献
35.
The present paper describes the development and validation of a normal-phase liquid chromatography-mass spectrometry (NP-HPLC-MS) method for the screening and quantification of vitamin E constituents in human plasma and food matrixes. Liquid-liquid extraction combined with isotope dilution was applied to extract the lipophilic target analytes. Baseline separation of alpha-tocopherylacetate, alpha-tocopherol, alpha-tocotrienol, alpha-tocopherylquinone, beta-tocopherol, gamma-tocopherol, beta-tocotrienol, gamma-tocotrienol, delta-tocopherol, and delta-tocotrienol was achieved utilizing a normal-phase amine column operated with n-hexane and 1,4-dioxane as solvents. Detection was achieved by positive-ion atmospheric-pressure chemical ionization (APCI). Key features of the method are lower limits of detection, 3-51 nmoles/L; lower limits of quantification, 8-168 nmoles/L; linearity coefficients, 0.9778-0.9989; linear ranges, 0.01-29 micromol/L; recoveries, 53-92%; accuracies, 99-103%; intraday precisions, 2-17%; interday precisions, 5-18%; and suppression values, 0-29%. Fragmentation of tocopherols was studied by tandem mass spectrometry, and a fragmentation scheme for tocotrienols/tocopherols is postulated. Neutral-loss and precursor-ion scan experiments were performed for targeted discovery of oxidation products of tocopherols in human blood and fish oil, the latter being an important food component. The presented data suggest that this method will help to expand the number of quantified/discovered vitamin E constituents detected in food products and analyzed during human/animal trials in order to give a more comprehensive picture to nutritionists about the fate of vitamin E. 相似文献
36.
B Gérard MF Le Heuzey G Brunie P Lewine MC Saiag V Cacheux F Da Silva M Dugas MC Mouren-Simeoni J Elion B Grandchamp 《Canadian Metallurgical Quarterly》1997,40(3):139-144
The Sense of Coherence Scale is used frequently world-wide and is thought to be appropriate to any population. The purpose of this study was to highlight some of the potential limitations of the scale. Fifteen members of the Pentecostal Movement described several difficulties in completing the scale, especially items measuring manageability and comprehensibility. The following three statements indicate the nature of their interpretation of the items and the ambiguity of their answers as they argued that: (1) the concept of 'I' was interpreted as 'I and God', (2) it is not necessary to understand everything in life, because it is enough that God understands, and (3) life is meaningful in itself because of the salvation. According to this interpretation of the items, every proposed answer could be suitable and consequently, the scores can readily be misconstrued. Many of the respondents proposed additions or changes in the wording to make the scale more suitable. The strong ego-centred items seem to be inappropriate for the participants in this study and other populations might also be confronted with similar difficulties. 相似文献
37.
Srinivasan Priya Jacques Robichaud Marie-Claude Méthot Subramanian Balaji James M. Ehrman Bao-Lian Su Yahia Djaoued 《Journal of Materials Science》2009,44(24):6470-6483
High surface area titanium glycolate microporous multi-faceted nanorods were synthesized from the reaction of titanium alkoxides
(Ti(OEt)4, Ti(O
i
Pr)4, or Ti(O
n
Bu)4) with ethylene glycol, using a sol–gel reflux method. The specific surface area of the as-synthesized titanium glycolate
nanorods obtained from Ti(OEt)4 is ~480 m2/g. A hot water treatment at 90 °C for 1 h transformed the titanium glycolate microporous nanorods into mesoporous anatase
TiO2 nanorods. The shape of the nanorods was conserved after hot water treatment and the microporous to mesoporous transformation
took place without significant change in the surface area (477 m2/g). Micro Raman spectroscopy, scanning electron microscopy, transmission electron microscopy, X-ray diffraction, solid state
NMR, and nitrogen adsorption/desorption were used to characterize the samples. As a demonstration of potential applications,
the thus formed mesoporous anatase TiO2 nanorods were tested for their photocatalytic efficiency in the degradation of crystal violet, and a photodegradation mechanism
is proposed. 相似文献
38.
Mounia Arkoun France Daigle Richard A. Holley Marie Claude Heuzey Abdellah Ajji 《Packaging Technology and Science》2018,31(4):185-195
Shelf life and safety of minimally processed food are crucial for both consumers and the food industry. This study investigates the in vitro and in situ efficiency of electrospun chitosan‐based nanofibers (CNFs) as inner part of a multilayer packaging in maintaining the quality of unprocessed red meat. Activated CNF‐based packaging (CNFP) were obtained by direct electrospinning of chitosan/poly(ethylene oxide) solutions on top of a conventional multilayer food packaging. The electrospinning solutions were firstly characterized at the molecular level, mainly in terms of zeta potential and viscoelastic properties, and the evolution of the conformational structure was correlated to the nanofiber formation process. The oxygen and water vapor barrier properties of CNF‐based (CNFP) meat packaging were also investigated. The in vitro antibacterial activity of CNFs was determined against Escherichia coli, Salmonella enterica serovar Typhimurium, Staphylococcus aureus, and Listeria innocua, bacteria commonly incriminated in the alteration of food products. The efficiency of the CNFP materials against meat spoilage by E. coli was also assessed. Our results indicate that the electrospinning of CS is a multifactorial process and fiber formation requires the choice of a good solvent, high electrical conductivity, moderate surface tension, optimum viscoelastic properties, and sufficient chain flexibility and entanglement. The results also indicate that all the tested bacterial strains were significantly sensitive to the action of CNFs. The in situ bioactivity against E. coli showed the potential of CNFP as bioactive nanomaterial barriers to meat contamination by extending the shelf life of fresh meat up to 1 week. 相似文献
39.
The utilization of poly(ε-caprolactone) (PCL)/poly(methyl methacrylate-co-methacrylic acid)-based semi-Interpenetrating Polymer Networks as nanostructured precursors provides a straightforward and effective route for engineering COOH-functionalized nanoporous networks. Such functional frameworks can be used as cation-exchange supports in Ion-Exchange Chromatography for the separation of proteins, provided the structures contain a significant initial content of carboxylic acid functions. This investigation illustrates the major role played by the presence of the interconnected pores generated by the oligoester template in the protein retention. The resolution turns out to be better than that obtained with a classically prepared porous support using an organic solvent as a porogen. 相似文献
40.
Breton MC Garneau M Fortier I Guay F Louis J 《The Science of the total environment》2006,370(1):39-50
The aim of this study is to evaluate the influence of meteorological factors on Ambrosia pollen concentrations and its impact on medical consultations for allergic rhinitis of residents from various socio-economic levels in Montréal (Québec, Canada) between 1994 and 2002. The study was conducted to recognize the sensitivity of pollen productivity to daily climate variability in order to estimate the consequences on human health vulnerability in the context of global climate change. Information related to medical consultations for allergic rhinitis due to pollen comes from the Quebec Health Insurance Board (Régie de l'assurance-maladie du Québec). Ambrosia pollen concentration was measured by the Aerobiology Research Laboratories (Nepean, Ontario). Daily temperature (maximum, minimum, and mean) and precipitation data were obtained from the Meteorological Service of Canada. Socio-economic data come from the 1996 and 2001 census data of Statistics Canada. Between 1994 and 2002, during the Ambrosia pollen season, 7667 consultations for allergic rhinitis due to pollen were recorded. We found a significant association between the number of medical consultations and pollen levels. Significant associations were detected for over-consultation the day of exposure, 1, 2, 3 and 5 days after exposure to high levels of pollen. The consultation rate is higher from low-income residents (3.10 consultations per 10,000 inhabitants) than for high-income (1.65 consultations per 10,000 inhabitants). Considering the demonstrated impact of pollen levels on health, it has become critical to ensure adequate monitoring of Ambrosia and its meteorological sensivity in the context of the anticipated climate change and its potential consequences on human health. 相似文献