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411.
    
Native potato starch has been modified with allylglycidyl ether (AGE) under various reaction conditions including different sodium hydroxide and AGE concentrations, reaction temperatures and times. 1H‐NMR and FT‐IR were used to analyze the products. AGE‐modified starch, with two degrees of substitution (DS), namely DS = 1.3 and DS = 2.3, was synthesized and used for preparation of a new family of crosslinked composites reinforced with various amounts of bleached softwood fibres. Composite premixes of modified starch, wood fibres and ethylene glycol dimethacrylate (EGDA) were cured in a hot press using 2% (w/w) of benzoyl peroxide at 150°C under high pressure for 10 min. The matrix with high degree of substitution exhibited good processability and was easily processed even for the highest fibre contents, up to 70% (w/w). In addition, scanning electron micrographs showed good dispersion and adhesion between the starch matrix with high degree of substitution and fibre. The original poor mechanical properties of the cured modified starch were markedly improved by the addition of wood fibres. In the extractions tests cured high‐DS and low‐DS composite samples showed weight losses in the range of 1 and 15% (w/w), respectively. No unreacted crosslinker ethylene glycol dimethacrylate was detected in the solutes as determined by NMR.  相似文献   
412.
    
Digital typefaces for computer graphics and multimedia applications should be capable of supporting operations such as font variations, transformations. deformations and blending. A powerful implementation of such operations must rely on the inherent typographic attributes of the typeface. However, even today's most advanced typeface representations support only geometric outline representations and basic font variations. In this paper we discuss high-level typeface representations which we term Parametric Typographic Representations (PTRs). We present an algorithm for automatically extracting typographic elements of typefaces from their outline representation, which, is an essential initial step in converting typefaces from outline representations to PTRs. The extracted typographic elements include serifs, bars. sterns, slants, bows, arcs, curve stems and curve bars. Most notable is the treatment of serifs, which are represented by finite-automata. The algorithm only needs to learn a serif type once, and is then capable of automatically recognizing it in different typefaces. We show an application of a PTR for automatic high-quality hinting of fonts, which is one of the most important stages in, digital font production. Our system was used to generate hints for dozens of thousands of Kanji, Roman and Hebrew characters.  相似文献   
413.
The capacity of the Chinese wind power sector has increased rapidly over the past half-decade, essentially doubling every year since 2005. The purpose of this paper is to describe the industry’s recent development and to discuss some of the policies and policy challenges related to the particular business environment in China. Three issues are highlighted: pricing policies, transmission capacity, and the structure of the equipment manufacturing industry, where substantial overcapacity is emerging as a serious problem.  相似文献   
414.
The effects of geocell reinforcement on the behavior of shell foundations were studied using PLAXIS 3D finite element software. For this purpose, conical and pyramidal geometries were adopted as shell foundations. The real honeycomb shape of geocell and rigid body behavior of shells were simulated in PLAXIS 3D. The numerical models for shell foundations and geocell reinforced foundations were separately validated using several laboratory studies in the literature. The validated models were extended to the shell foundations resting on geocell reinforced sandy beds. The inclusion of geocell-reinforcement provided more than 70% reduction in the settlement of pyramidal and conical shell foundations. The stress transferred to the sand beds were reduced and distributed a wider area compared to the unreinforced cases. The maximum improvement in the bearing capacity and the settlement were observed in the case of conical shell foundation. The effect of adopted geocell and shell configuration on the foundation behavior was also analyzed for realistic prototype foundation size.  相似文献   
415.
In this study reactor core geometrical optimization of 200 MWt Pb–Bi cooled long life fast reactor for hydrogen production has been conducted. The reactor life time is 20 years and the fuel type is UN-PuN. Geometrical core configurations considered in this study are balance, pancake and tall cylindrical cores. For the hydrogen production unit we adopt steam membrane reforming hydrogen gas production. The optimum operating temperature for the catalytic reaction is 540 °C. Fast reactor design optimization calculation was run by using FI-ITB-CHI software package. The design criteria were restricted by the multiplication factor that should be less than 1.002, the average outlet coolant temperature 550 °C and the maximum coolant outlet temperature less than 700 °C. By taking into account of the hydrogen production as well as corrosion resulting from Pb–Bi, the balance cylindrical geometrical core design with diameter and height of the active core of 157 cm each, the inlet coolant temperature of 350 °C and the coolant flow rate of 7000 kg/s were preferred as the best design parameters.  相似文献   
416.
The effect of gamma radiation on moisture content, total mold counts, Aspergillus counts, and aflatoxins of three hot pepper hybrids (Sky Red, Maha, and Wonder King) was investigated. Whole dried peppers packed in polyethylene bags were gamma irradiated at 0 (control), 2, 4, and 6 kGy and stored at 25°C for 90 days. Gamma radiation proved to be effective in reducing total mold and Aspergillus counts in a dose-dependent relationship. Total mold counts in irradiated peppers immediately after treatments were significantly lowered compared with those in nonirradiated samples, achieving 90 and 99% reduction at 2- and 4-kGy doses, respectively. Aspergillus counts were significantly reduced, by 93 and 97%, immediately after irradiation at doses of 2 and 4 kGy, respectively. A radiation dose of 6 kGy completely eliminated the population of total molds and Aspergillus fungi. The evolution of total molds in control and irradiated samples indicated no further fungal proliferation during 3 months of storage at 25°C. Aflatoxin levels were slightly affected by radiation doses of 2 and 4 kGy and showed a nonsignificant reduction of 6% at the highest radiation dose of 6 kGy. The distinct effectiveness of gamma radiation in molds and aflatoxins can be explained by the target theory of food irradiation, which states that the likelihood of a microorganism or a molecule being inactivated by gamma rays increases as its size increases.  相似文献   
417.
Meat texture and some biochemical characteristics that could influence meat tenderness were studied in rabbit loins. Rabbits from three synthetic lines were compared, lines V and A selected for litter size at weaning and line R selected for growth rate between weaning and slaughter time. The activities of cathepsins, collagen content and textural properties measured by Warner-Bratzler (WB) shear device and by the texture profile analyses (TPA) test were measured. Line R was more tender than line V and line A had an intermediate tenderness, Rabbit meat from line R had higher activity of cathepsins B and B + L, lower total collagen content and lower cohesiveness, springiness and chewiness, shear force and total work (area under the curve obtained with WB device) than line V. Line A had an intermediate texture between lines R and V. Our results show evidence of genetic variation between lines in rabbit meat tenderness.  相似文献   
418.
The complexation of Cd2+, Zn2+, and both together with the phytochelatin (gamma-Glu-Cys)3Gly is studied by differential pulse polarography, and data are analyzed by multivariate curve resolution by alternating least squares (MCR-ALS). MCR-ALS yields the respective unitary voltammograms and concentration profiles of the resolved components, which contain information on the relative stabilities and stoichiometries of the formed complexes. The analysis of these results shows, for the Cd2+/(gamma-Glu-Cys)3Gly system, the presence of different kinds of bound Cd2+. For the Zn2+/ (gamma-Glu-Cys)3Gly system, the poor definition of the reduction signals of the complexes prevents a clear discrimination among differently bound Zn2+ ions. Atentative complexation/ electrochemical model is proposed for when both metal ions, Cd2+ and Zn2+, compete toward complexation, and some of the corresponding equilibrium constants are estimated.  相似文献   
419.
Photochemical decomposition of persistent perfluorocarboxylic acids (PFCAs) in water by use of persulfate ion (S2O8(2-)) was examined to develop a technique to neutralize stationary sources of PFCAs. Photolysis of S2O8(2-) produced highly oxidative sulfate radical anions (SO4-), which efficiently decomposed perfluorooctanoic acid (PFOA) and other PFCAs bearing C4-C8 perfluoroalkyl groups. The major products were F- and CO2; also, small amounts of PFCAs with shorter than initial chain lengths were detected in the reaction solution. PFOA at a concentration of 1.35 mM (typical of that in untreated wastewater after an emulsifying process in fluoropolymer manufacture) was completely decomposed by a photochemical system with 50 mM S2O8(2-) and 4 h of irradiation from a 200-W xenon-mercury lamp. The initial PFOA decomposition rate was 11 times higherthan with photolysis alone. All sulfur-containing species in the reaction solution were eventually transformed to sulfate ions by this method. This method was successfully applied to the decomposition of perfluorononanoic acid contained in a floor wax solution.  相似文献   
420.
How large is the social cost penalty if one makes the wrong choice because of uncertainties in the estimates of the costs and benefits of environmental policy measures? For discrete choices there is no general rule other than the recommendation to always carefully compare costs and benefits when introducing policies for environmental protection. For continuous choices (e.g., the ceiling for the total emissions of a pollutant by an entire sector or region), it is instructive to look at the cost penalty as a function of the error in the incremental damage cost estimate. Using abatement cost curves for NOx, SO2, dioxins, and CO2, this paper evaluates the cost penalty for errors in the following: national emission ceilings for NOx and SO2 in each of 12 countries of Europe, an emission ceiling for dioxins in the UK, and limits for the emission of CO2 in Europe. The cost penalty turns out to be remarkably insensitive to errors. An error by a factor of 3 due to uncertainties in the damage estimates for NOx and SO2 increases the total social cost by at most 20% and in most cases much less. For dioxins, the total social cost is increased by at most 10%. For CO2, several different possible cost curves are examined: for some the sensitivity to uncertainties is greater than for the other pollutants, but even here the penalty is less than 30% and in most cases much less if the true damage costs are twice as high as the ones estimated. The paper also quantifies the benefit of improving the accuracy of damage cost estimates by further research.  相似文献   
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