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51.
Synthesis of poly(N‐isopropylacrylamide) by distillation precipitation polymerization and quantitative grafting on mesoporous silica 下载免费PDF全文
Sushilkumar A. Jadhav Valentina Brunella Ivana Miletto Gloria Berlier Dominique Scalarone 《应用聚合物科学杂志》2016,133(44)
In this work, syntheses of thermoresponsive poly(N‐isopropylacrylamide) (PNIPAM) with different molecular weights were carried out in ethanol by distillation precipitation polymerization (DPP) technique. The synthesized polymers were fully characterized by attenuated total reflection Fourier‐transform infrared (ATR‐FTIR) spectroscopy, nuclear magnetic resonance spectroscopy, and size exclusion chromatography techniques. The lower critical solution temperatures of the polymers were determined with differential scanning calorimetry. A simple and versatile method for the in situ synthesis and grafting of PNIPAM on mesoporus silica nanoparticles (MSNs) with improved control over quantitative grafting is devised. The PNIPAM grafted MSNs were characterized with ATR‐FTIR, thermogravimetric analysis, transmission electron microscopy, and dynamic light scattering analyses. From the results obtained it is showed that quantitative grafting of PNIPAM on MSNs from 1 to 20% by weight can be tuned by manipulating the in situ DPP reaction conditions. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 44181. 相似文献
52.
Multimerization behaviour of single chain Fv variants for the tumour-binding antibody B72.3 总被引:2,自引:0,他引:2
Desplancq Dominique; King David J.; Lawson Alastair D.G.; Mountain Andrew 《Protein engineering, design & selection : PEDS》1994,7(8):1027-1033
A systematic study has been performed on the relationship betweenlinker length, relative orientation of variable domains, multimerizationbehaviour and antigen binding activity for single chain Fvs(scFvs) of the tumour-binding antibody B72.3. Thirteen scFvvariants with linkers comprising up to six repeats of the motifGly-Gly-Gry-Gly-Ser were studied. All these scFvs showed a tendencyto form dimers or higher molecular weight species, and thistendency decreased with increasing linker length. The dimersand higher molecular weight forms may arise from head to tailintermolecular association of VH and VL domains. For each linkerlength, scFvs with the organization VL-linker-VH showed greaterbinding activity than those with the organization VH-linker-VL.In fact, for the latter organization only the variant with a30 amino acid linker showed good binding activity, suggestingthat (0 for B72.3 the C-tenninus of VH or the N-tenninus ofVL makes a structural contribution to antigen binding, and (ii)shorter linkers interfere with this contribution. Antigen bindingstudies on scFvs should be interpreted with caution becauseof their tendency to multlmerize. Such multimerization can beminimized by using linkers longer than those in common use 相似文献
53.
Véronique Gauthier Benoît Cochepin Sylvain Dubois Dominique Vrel 《Journal of the American Ceramic Society》2006,89(9):2899-2907
Ti3 SiC2 is synthesized by self-propagating high-temperature synthesis (SHS) of elemental titanium, silicon, and graphite powders. The reaction paths and structure evolution are studied in situ during the SHS of the 3Ti+Si+2C mixture by time-resolved X-ray diffraction coupled with infrared thermography. The proposed reaction mechanism suggests that Ti3 SiC2 might be formed from Ti–Si liquid phase and solid TiC x . Finally, the effect of the powders starting composition on the Ti3 SiC2 synthesis is studied. For the investigated initial mixtures, TiC x is always formed as a major impurity together with the Ti3 SiC2 phase. 相似文献
54.
Application of ATR-FTIR for a rapid and simultaneous determination of sugars and organic acids in apricot fruit 总被引:1,自引:0,他引:1
Sylvie Bureau David Ruiz Maryse Reich Barbara Gouble Dominique Bertrand Jean-Marc Audergon Catherine M.G.C. Renard 《Food chemistry》2009
A simple, fast and accurate Fourier transform mid-infrared spectroscopy method was developed for simultaneously determining sugar and organic acid contents in apricot fruit slurries using the attenuated total reflectance. The potential of this method coupled with chemometric techniques based on partial least squares was assessed by comparison with currently used enzymatic determination of sucrose, glucose, fructose, malic acid and citric acid. Fruits of eight contrasted cultivars harvested at different ripening stages were used in this study and randomly divided in a calibration set (505 apricots) and in a validation set (252 apricots). The most suitable region was found in the range between 1500 and 900 cm−1. Good prediction performances were obtained (R2 ? 0.74 and RMSEP ? 18%). Results concerning the prediction of other quality traits such as firmness, skin colour, ethylene production, soluble solids content and titratable acidity were discussed. 相似文献
55.
Sylvie Bureau David Ruiz Maryse Reich Barbara Gouble Dominique Bertrand Jean-Marc Audergon Catherine M.G.C. Renard 《Food chemistry》2009
A non-destructive optical method based on near-infrared spectroscopy has been used for the evaluation of apricot fruit quality. Diffuse reflectance measurements (800–2500 nm), physical, physiological and biochemical measurements were performed individually on 877 apricot fruits from eight contrasted cultivars harvested at different ripening stages. Relationships between spectral wavelengths and quality attributes were evaluated by application of chemometric techniques based on partial least squares (PLS) on fruit set divided randomly into two groups: 598 fruits for calibration and 279 for validation. Good prediction performance was obtained for soluble solids and titratable acidity with correlation coefficients of 0.92 and 0.89 respectively and root mean square errors of prediction of 0.98% Brix and 3.62 meq 100 g−1 FW respectively. For the other quality traits such as firmness, ethylene, individual sugars and organic acids, the prediction models were not satisfactorily accurate due to the high error of calibration and prediction. 相似文献
56.
Aggregates were formed by heating mixtures of whey protein isolate (WPI) and pure κ-casein or sodium caseinate at pH 7 and 0.1 M NaCl. The aggregates were characterized by static and dynamic light scattering and size exclusion chromatography. After extensive heat-treatment at 80 °C for 24 h, almost all whey proteins and κ-casein formed mixed aggregates, but a large proportion of the sodium caseinate did not aggregate. At a given WPI concentration the size of the aggregates decreased with increasing κ-casein or sodium caseinate concentration, but the overall self-similar structure of the aggregates was the same. The presence of κ-casein or caseinate therefore inhibited growth of the heat-induced whey protein aggregates. The results were discussed relative to the reported chaperone-like activity of casein molecules towards heat aggregation of globular proteins. 相似文献
57.
Staffan Jacobsson Anna Bergek Dominique Finon Volkmar Lauber Catherine Mitchell David Toke Aviel Verbruggen 《Energy Policy》2009
The recent EU Commission proposal for promoting the supply of power from renewable energy sources was originally based on a pan-European, harmonised tradable green certificate (TGC) scheme. We suggest, on the basis of a multi-disciplinary analysis, that a pan-EU TGC system is not the way forward for Europe. It is vital that the Commission (and the majority of Member States) avoids implementation of such policy designs put forward by a coalition of vested interests. They should instead look at, and act upon, the available evidence from those countries that have experimented with TGCs (e.g. Flanders, UK and Sweden) and design policies that stand a better chance of meeting the criteria of effectiveness, efficiency and equity. In particular, the policies must enable EU to meet the immense innovation/industrialisation challenge by inducing the development of a capital goods industry that can, eventually, diffuse a broad range of technologies that use renewable energy sources. Only then we can acquire an ability to implement an industrial revolution in the energy system in a way that broadly meets the criteria of effectiveness and dynamic efficiency. 相似文献
58.
Giovanni Crupi Dominique M. M.‐P. Schreurs Alina Caddemi Antonio Raffo Giorgio Vannini 《国际射频与微波计算机辅助工程杂志》2010,20(1):87-93
The present article analyzes in detail different intrinsic small‐signal models for transistors. Particular attention is devoted to the non‐quasi‐static effects, which play a crucial role at microwave and millimeter‐wave frequencies. The advantages and disadvantages of these different equivalent circuit topologies are analyzed from both theoretical and experimental standpoints. This study clearly proves that best choice among these model representations depends on the specific device technology besides the investigated frequency range. © 2009 Wiley Periodicals, Inc. Int J RF and Microwave CAE, 2010. 相似文献
59.
Honorine Angue Mintsa Gilles Roy Cong Tam Nguyen Dominique Doucet 《International Journal of Thermal Sciences》2009,48(2):363-371
This paper presents effective thermal conductivity measurements of alumina/water and copper oxide/water nanofluids. The effects of particle volume fraction, temperature and particle size were investigated. Readings at ambient temperature as well as over a relatively large temperature range were made for various particle volume fractions up to 9%. Results clearly show the predicted overall effect of an increase in the effective thermal conductivity with an increase in particle volume fraction and with a decrease in particle size. Furthermore, the relative increase in thermal conductivity was found to be more important at higher temperatures. Obtained results compare favorably with certain data sets and theoretical models found in current literature. 相似文献
60.
Dynamic wetting and heat transfer at the initiation of aluminum solidification on copper substrates 总被引:1,自引:0,他引:1
Dominique Bouchard Sébastien Leboeuf Jean-Paul Nadeau Roderick I. L. Guthrie Mihaiela Isac 《Journal of Materials Science》2009,44(8):1923-1933
Dynamic wetting and heat transfer during the start of solidification were studied with the help of molten aluminum droplets
falling from a crucible onto a copper substrate. A high-speed camera captured the change in the spreading droplet’s geometry,
while thermocouple, inserted inside the substrate, allowed a heat transfer analysis to be performed. Droplet spreading factors
and interfacial heat fluxes were then used to, respectively, characterize dynamic wetting and heat transfer for the various
experimental conditions explored. These were: (1) effects of chemical composition of the aluminum alloy, (2) initial temperature
of the substrate, (3) surface roughness of the substrate, and (4) composition of the gaseous atmosphere. The experiments were
all carried out in gaseous atmospheres containing oxygen in sufficient amount to form oxide skins at the surface of the droplets
and the substrates. The results showed instances where an improvement in the dynamic wetting was accompanied by an increase
in heat transfer during the early stages of solidification but this was not systematic. In these cases where a positive correlation
was not observed, it was postulated this was caused by factors such as variations in the oxidation at the surface of the substrates
and the droplets as well as gas trapped at the interface between the droplets and the substrates.
Sébastien Leboeuf formerly with the Aluminum Technology Centre and McGill University. 相似文献