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81.
Ceramides and cerebrosides were isolated from immature and mature soybeans, and structures of the constituents were investigated. As component fatty acids, normal, 2-hydroxy and 2,3-dihydroxy acids were found in ceramides, whereas only normal and 2-hydroxy acids were identified in cerebrosides. The principal fatty acid component was 2-hydroxylignoceric acid in ceramides, and 2-hydroxypalmitic acid in cerebrosides. Sphingoids in ceramides consisted mainly of trihydroxy bases, with 4-hydroxy-trans-8-sphingenine being predominant. In contrast, cerebrosides contained mainly dihydroxy bases, the principal constituent beingtrans-4,trans-8-sphingadienine. The only sugar in cerebrosides was glucose. The constituents of the two sphingolipids were similar to each other in immature and mature seeds. Possible metabolic relations of plant sphingolipids, based on composition, are discussed.  相似文献   
82.
Hun  Yong  SHIN  Hwayong  KIM 《中国化学工程学报》2002,10(6):661-665
Quantitative representation of complicated behavior of fluid mixtures in the critical region by any of equation-of-state theories remains as a difficults thermodynamic topics to date.In the present work,a computational efforts were made for representing various types of critical loci of binary water with hydrocarbon systems showing Type Ⅱ and Type Ⅲ phase behavior by an elementary equation of state[called multi-fluid nonrandom lattice fluid EOS(MF-NLF EOS)]based on the lattice statistical mechanical theory.The model EOS requires two molecular parameters which representing molecular size and interaction energy for a pure component and single adjustable interaction energy parameter for binary mixtures.Critical temperature and pressure data were used to obtain molecular size parameter and vapor pressure data were used to obtain interaction energy parameter.The MF-NLF EOS model adapted in the present study correlated quantitatively well the critical loci of various binary water with hydrocarbon systems.  相似文献   
83.
This paper deals with a method of estimating single electrode heat balances during the electrolysis of molten NaCl-ZnCl2 in a cell using a-alumina diaphragm. By measuring the thermoelectric power of the thermogalvanic cells: (T) Na/-alumina/NaCl-ZnCl2/-alumina/Na(T+dT) and (T) C,Cl2/NaCl-ZnCl2/Cl2,C(T+dT) the single electrode Peltier heat for sodium deposition and for chlorine evolution at 370° C were estimated to be –0.026±0.001 JC–1 and+0.614±0.096 J C–1, respectively.  相似文献   
84.
A semi-cylindrical fluidized bed of 15 cm internal diameter, equipped with a transparent flat glass plate for the front wall, was employed to visually observe bubbles in the bubbling to slugging transition regime and in the slugging regime. Five kinds of perforated distributors were used to investigate the effect of distributor type on the bubble size and the bubble rise velocity. The average bubble size was not affected by distributor type in these flow regimes, and could be predicted by Darton et al's correlation (1974)of hole number 22. In other words, this comes from the inapplicability of the correlation to the slugging regime. The bubble rise velocity agreed well with Allahwala et al's correlation (1979) and was not affected by the type of distributor.  相似文献   
85.
Japan and Sweden have similar ambitions and both similarities and differences when it comes to provide long term care (LTC) for their old age citizens. The study compares cost increase for LTC in Japan and Sweden in the time period 2000–2010 by decomposing the changes in costs into changes in the size of the old age population (65 years and above) , the distribution on level of dependency /disability by age-group and gender, the volume of provided LTC services in relation to level of dependency/disability and the unit costs for provided services. The analysis of needs of LTC services is based upon nationally representative sample surveys population studies completed in each country: Nihon University Japanese Longitudial Study of Aging and the Swedish Survey of Living Conditions with 19. 602 and 9.433 observations respectively. Data on LTC services provision by level of dependency/ disability is taken from nine Japanese municipalities collected by assessments in the LTCI-system and from surveys in eight Swedish municipalities. It is shown by the analysis that the rapid cost increase in Japan in the period 2000–2010, 108 %, has mainly been driven by the increase in the old age population. However, another important factor in the period 2000–2005 has been increased provision of LTC services given level of dependency. In Sweden the cost increase depending on population increase has been countered by decreasing levels of disability by age-groupand gender. Services provision given needs of LTC has not increased very much. As a result the cost increase in the time period 2000–2010 has been much lower, +6 %.  相似文献   
86.
87.
Ni nanoparticles were synthesized by plasma-induced cathodic discharge electrolysis in LiCl–KCl–CsCl + NiCl2 at 573 K under 1 atm of Ar atmosphere. Ni nanoparticles with diameters of around 100 nm were obtained from the melt. It was also confirmed that particles predominantly grow at the surface of the melt, especially the region just under the discharge. Taking into account the above results, a novel type plasma-induced electrolytic cell has been designed and constructed; it operated successfully, a rotating Ni metal disk anode being adopted in order for the formed particles to be quickly removed from the region just under the discharge and be continuously transferred to the inner wall of the cold container. By using this novel type plasma-induced electrolytic cell, Ni nanoparticles with diameters of around 50 nm could be obtained.  相似文献   
88.
Synthesis of zeolite A from aluminoborosilicate glass used in liquid crystal display (LCD) panel glass substrate was attempted. Mixture of aluminoborosilicate glass and sodium aluminate was hydrothermally treated with sodium hydroxide solution for 10.8–345.6 ks at 368–423 K. Aluminoborosilicate glass was also acid treated with nitric acid before hydrothermal treatment. Obtained samples were characterized by X‐ray diffraction and scanning electron microscope observation. Zeolite A, hydroxysodalite, and zeolite P were synthesized, and with the specific conditions of hydrothermal treatment, a single phase of zeolite A was successfully obtained. Acid treatment was effective for synthesis of a single phase of zeolite A, because the components of aluminoborosilicate other than SiO2 preferentially eluted for acid solution and during following hydrothermal treatment SiO2 was supposed to elute for alkaline solution. Cation‐exchange capacities (CECs) were investigated for these products. It was clarified that CEC of the product with a single phase of zeolite A obtained from aluminoborosilicae glass was 4.2 mol/kg. CEC of the product consisted of zeolite A and hydroxysodalite was 3.9 mol/kg, and the one consisted of zeolite A, hydroxysodalite, and zeolite P was 2.6 mol/kg. This results shows that aluminoborosilicate glass could be expected to be recycled in zeolite A with good CEC by the appropriate process.  相似文献   
89.
We propose a novel type of highly efficient solar cells: intermediate-band-assisted hot-carrier solar cells (IB-HC-SCs). Carriers are generated by two-step photo-excitation via intermediate bands, and extracted through energy-selective contacts before they are completely thermalized. The two-step excitation dramatically reduces entropy generation associated with hot-carrier extraction. As a result, limiting conversion efficiency is significantly improved to be around 60% (0.1 sun)-70% (1000 sun), even though considering a finite thermalization time of hot carriers being 1 ns. This improvement is contrasting to the fact that the limiting conversion efficiency of usual hot-carrier cells under 1 sun irradiation is higher only slightly than the Shockley-Queisser limit (34%), because of the remarkable entropy generation.  相似文献   
90.
We report the structural changes inside germania glass induced by femtosecond laser pulses. Inspection by polarization microscopy and secondary electron microscopy indicate that the periodic nanostructures consist of oxygen defects such as ODCs (oxygen deficient centers) and NBOHCs (nonbridging oxygen hole centers) for laser pulse energy less than 0.2 μJ. However, the glass network was dissociated and O2 molecules were generated for laser pulse energy greater than 0.4 μJ. Two different structural changes, form‐birefringence and dissociation, were induced in GeO2 glass, depending on the laser pulse energy. The form‐birefringence exhibited by the nanogratings in GeO2 glass is larger than that in SiO2 glass for pulse energy less than 0.2 μJ, as the density of nanovoids enclosed by ODCs in GeO2 glass is higher than that in SiO2 glass. Arrhenius plots of the phase retardation caused by the nanogratings in GeO2 and SiO2 indicate that the oxygen defects are relaxed at a temperature 100°C above the glass‐transition temperature.  相似文献   
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