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1.
Journal of Materials Science - We develop several inference methods to estimate the position of dislocations from images generated using dark-field X-ray microscopy (DFXM)—achieving...  相似文献   
2.
Construction of low-income housing projects is a recurring process and is associated with uncertainties that arise from the unavailability of resources. This paper presents a case study that discusses how computer simulation and optimisation are used to aid government agencies and/or contractors in planning of such projects. It illustrates the optimisation of project objectives, taking into consideration the interaction amongst involved resources. As such, total duration and the associated total costs, including direct and indirect costs, can be estimated and optimised. One Youth Habitation project that is executed in 6th of October City in Egypt is analysed in a step-by-step procedure to demonstrate the capability of proposed computer simulation and optimisation prototype (named LIHouse{_}Sim) in the modelling construction of low-income housing projects using bearing block walls with hollow core technique. The presented tool proves its practicality to contractors in estimating the time and costs of the recurring process of low-income housing construction, considering complex interdependencies between construction resources and the uncertainties associated with construction activities. The LIHouse{_}Sim prototype is used to perform a wide analysis for the alternative of the effective optimisation criteria in the bearing block walls/hollow core technique and for the genetic algorithm optimisation approach elements.  相似文献   
3.
Glasses of the 33.5Li2O-66.5P2O5-xV2O5 (mol. %) system with (0 ≤ x ≤ 5) were prepared by the normal melting and annealing technique. Their physical and spectroscopic properties such as X-ray powder diffraction (XRD), density, infrared spectroscopy and electrical conductivity were investigated. The composition dependent density shows an initial decrease at 0.1 mol.% of V2O5 followed by an increase in density with further addition of the V2O5 content. The structure of these glasses has been studied by recording the Fourier-transform infrared spectroscopy (FTIR) over the range 400–1800 cm?1. Vibrational modes are assigned to different types of phosphate groups in the glass network. The temperature (333–452 K) and composition dependence of direct current (DC) electrical conductivity were measured. The electric conductivity is observed to increase with the first addition of vanadium oxide reflecting the presence of V4+ions that take part within modifying positions in the glass network .Then, the electric conductivity is found to decrease with the further increase in the content of V2O5 up to 5 mol.% reflecting the formation of V5+ions that take part as network forming positions in the glass network. The variations in density and electrical conductivity with V2O5 content are discussed in terms of changes in the glass structure.  相似文献   
4.
The objective of this work was to evaluate the quality of sterilised canned pea and corn in electro‐activated brine solutions at moderate temperatures. The lowest change in vitamin C was associated with the lowest heat treatment, while the short treatment time resulted in significant changes in texture and colour of vegetables. Best texture profile was obtained with the acid electro‐activated brine solution for pea and corn. The neutral electro‐activated brine solution resulted in a less firm texture for pea and corn. The green colour and brightness of canned pea were higher when neutral solution was used (a* = ?8.4 ± 0.3) than for the acidic one (a* = ?3.7 ± 0.6). The yellowness of corn was better with the neutral electro‐activated brine solution (b* = 36.32 ± 1.24) than with the acidic one (b* = 28.44 ± 2.39). Thirty‐three percent decrease of energy consumption was obtained using the electro‐activation technology.  相似文献   
5.
Using thick concrete covers in offshore and nuclear containment applications is increasing because it is a durability issue. Most crack width models indicate that increasing concrete covers results in increased crack spacing and hence increased crack width this means that thick concrete covers are detrimental to crack control. In this paper, tests were conducted on two groups of thick plates. Group I, included five specimens that had two concrete covers, 60 and 70 mm. Group II, included four thick heavy reinforced specimens; all specimens in this group had a clear concrete cover of 70 mm. Using thick concrete covers is a common practice in offshore and containment structures for nuclear power generation. The objective of testing both groups is to measure flexural crack widths under different load levels and, most importantly, under service loads. Group I was intended primarily to investigate the effect of increasing the cover and bar spacing on the crack width. Group II represents a unique experimental investigation in assessing the magnitude of crack width in full-scale thick plates under service loads. An analytical investigation is presented in this work. The main focus of this study is to evaluate the available codes’ models for estimating the crack width of thick concrete plates having thick concrete covers used for offshore and nuclear containment structure applications. It was concluded that crack control can still be achieved by limiting the spacing of the reinforcing steel despite using thick concrete covers.  相似文献   
6.
This study reports investigations on the chemical constituents and fumigant toxicity of Pistacia lentiscus L. (Anacardiaceae) essential oil against two major stored-date insects, carob moth Ectomyelois ceratoniae Zeller and Mediterranean flour moth Ephestia kuehniella Zeller. Results showed that P. lentiscus essential oil contained terpinene-4-ol (23.32%), α-terpineol (7.12%) and β-caryophyllene (22.62%) as major compounds. Fumigant toxicity tests showed that P. lentiscus oil was more toxic to E. kuehniella (LC50 = 1.84 μl/l, LC95 = 5.14 μl/l) than E. ceratoniae (LC50 = 3.29 μl/l, LC95 = 14.24 μl/l). The fecundity and hatching rate of both insects decreased with increases in concentration or exposure time to the oil. At 136 μl/l air, fecundities and hatching rates were respectively 35 eggs/female and 42.86% for E. ceratoniae and 78 eggs/female and 29.49% for E. kuehniella.  相似文献   
7.
The objective of this study was to compare the composition of fatty acids stored in the various parts of swordfish. Muscle and organ sections of a series of swordfish samples were collected. Their chemical analysis allowed the classification of swordfish as a semi-fatty fish, with its byproducts totalling 35.6% of the total fatty acids (TFA) and its white and red muscles (MR) 7.2%. The highest contents were found in the liver (26%), the gonads (4.7%) and the red muscle (RM) (4.5%). The UFA/SFA ratio as recommended by nutritionists is 3; in the liver, skin and RM samples this ratio was, respectively, 3.5, 2.8 and 2.7. There is a high level of unsaturated fatty acids (UFA) in swordfish. More than 40% of the muscular tissues are made up of polyunsaturated fatty acids (PUFA) of the n-3 series (EPA + DHA). The byproducts contain more than 30% of monounsaturated acids characterised by the fatty acids of the n-9 series and particularly by oleic acid.  相似文献   
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In this paper, fabrication, characterization, and physiological application of a miniaturized amperometric lactate biosensor are described. The sensor is based on cross-linked lactate oxidase and tetrathiafulvalene-tetracyano-quinodimethane (TTF-TCNQ) charge transfer complex. The sensor was developed for continuous quantitative measurement of the lactate accumulation in ischemic myocardium under severe depletion of oxygen. The sensor was evaluated in vitro at an applied potential of 0.15 V vs Ag/AgCl; it proved to combine all the performance characteristics desired for the present application, such as proper response in absence of oxygen, good operational stability, good accuracy and precision (103.5 +/- 1.2%), adequate response time (t95% = 80 s), and wide linear dynamic range up to 27 mM (r = 0.9998) in N2-saturated solutions and at 37 degrees C. The prepared sensors (n = 12) showed sensitivity of 380 +/- 90 nA/mM, and a background current of 240 +/- 50 nA. The lower limit of detection is 0.4 +/- 0.15 mM with a S/N ratio equal to 3. Results obtained for direct lactate monitoring in ischemic rabbit papillary muscle under no-flow conditions and PO2 < 6 mm Hg are presented.  相似文献   
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