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101.
The future of coproducts from corn processing 总被引:4,自引:0,他引:4
Increased demand for ethanol as a fuel additive has resulted in dramatic growth in ethanol production. Ethanol is produced
from corn by either wet milling or dry-grind processing. In wet milling, the corn kernel is fractionated into different components,
resulting in several coproducts. Wet-milling plants are capital intensive because of equipment requirements; they produce
large volumes of ethanol and are corporate owned. In dry-grind processing, the corn kernel is not fractionated and only one
coproduct, distillers’ dried grains with solubles (DDGS), is generated. Dry-grind plants require less equipment and capital
than wet mills. They generate smaller volumes of ethanol, are producer owned, and add direct benefits to rural economies.
Most of the increase in ethanol production during the past decade is attributed to growth in the dry-grind industry. The marketing
of coproducts provides income to offset processing costs. For dry-grind plants, this is especially important, because only
one coproduct is available. Several issues could affect DDGS marketing. The increasing volume of DDGS accompanying ethanol
production could reduce market value; high phosphorous content could limit the use of DDGS, because of animal waste disposal
issues. Water removal is a costly processing step and affects the economics of ethanol processing. Technologies to remove
germ and fiber from DDGS could produce a new coproduct suitable for feeding to nonruminants; this would expand the markets
for DDGS. Reducing phosphorus in DDGS would sustain markets for conventional DDGS. The development of more efficient methods
of water removal would increase the efficiency of ethanol processing and reduce the costs of processing. New technologies
could contribute to greater stability of dry-grind plants. 相似文献
102.
Synthesis of magnetite nanoparticles by precipitation with forced mixing is presented. Using this method it is easy to obtain a high product saturation degree and the constant pH value of the reaction system. The TEM and XRD measurments show that the average size of the product magnetite particles is less than 6.0-nm in the condition of [Fe2+]/[Fe3+]=0.5. The magnetic properties of the samples are discussed. 相似文献
103.
Reverse Schreinemakers Method for Experimental Analysis of Mixed-Solvent Electrolyte Systems 总被引:1,自引:0,他引:1
A method based on Schreinemakers’s tie-line theory of 1893 is derived for determining the composition and phase amounts in
solubility experiments for multi-solvent electrolyte systems. The method uses the lever rule in reverse compared to Schreinemakers’s
wet residue method, and is therefore called the reverse Schreinemakers (RS) method. The method is based on simple mass balance
principles similar to the wet residues method. It allows for accurate determination of the mixed-solvent phase composition
even though part of the solvent may precipitate as complexes between solvent and salt. Discrepancies from determining the
composition of salt mixtures by pH titration are discussed, and the derived method significantly improves the obtained result
from titration. Furthermore, the method reduces the required experimental work needed for analysis of phase composition. The
method is applicable to multi-solvent systems and may be used for the determination of solid-phase compositions, similar to
Schreinemakers’s original “rest” method. An example calculation is presented for the Na2CO3-NaHCO3-MEG-H2O system. 相似文献
104.
105.
Layered lithiated Co- and Ni-oxide powders and thin films with rhombohedral (R
m) structure were prepared by a peroxo wet chemistry route from Li(I), Co(II) and Ni(II) acetate precursors and the addition of H2O2. XRD analysis revealed that xerogel films and powders possessed a typical layered structure. Layered (R
m) Li0.99Co1.01O2 powder and Li0.97Co1.03O2 films were formed around 500°C, while Li0.93Ni1.07O2 powder and Li0.94Ni1.06O2 oxide films were prepared around 550°C. The stoichiometry of the oxide films and powders was dependent on the heat-treatment temperature. The structure of sols, gels, xerogels and thin films was established from XRD spectra and from the FT-IR spectra, confirming their layered structure. 相似文献
106.
107.
The catalytic wet oxidation process is the most attractive process for small-scale hydrogen sulfide (H2S) removal from natural gas. The catalytic wet oxidation process is anticipated to be cost effective and simple so that it
can be used for treating sour gases containing small amounts of H2S and can be easily operated even in isolated sites. The development of effective catalyst is the key technology in the wet
catalytic oxidation of H2S. The scale of operation for the process has to be flexible so its use will not be limited by the flow rates of the gas to
be treated. The heterogeneous catalytic wet oxidation of H2S has been attempted on activated carbons, but the H2S removal capacity still shows the low removal efficiency. The catalytic wet oxidation of H2S was studied over Fe/MgO for an effective removal of H2S. In order to develop a sulfur removal technology, one has to know what surface species of catalyst are the most active.
This article discusses the following systematic studies: (i) the catalytic preparation to disperse Fe metal well on MgO support
for enhancing H2S removal capacity, (ii) the effect of the catalytic morphology on the activity of Fe/MgO for the H2S wet oxidation, (iii) the influence of precursor and support on the activity of Fe/MgO for catalytic wet oxidation of H2S to sulfur. 相似文献
108.
Eun-Ku Lee Kwang-Deog Jung Oh-Shim Joo Yong-Gun Shul 《Reaction Kinetics and Catalysis Letters》2004,82(2):241-246
Four different magnesium oxides were studied in the wet oxidation of H2S to sulfur. The H2S removal capacity of MgO in the catalytic wet oxidation strongly depends on the pore size distribution. The MgO with relatively
large pores (>100 ?) showed a high removal capacity of H2S. It is suggested that the large pore size favors H2S removal in the catalytic wet oxidation due to the limitation of diffusion.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
109.
110.
D. K. Kopeliovich Y. A. Malykh S. G. Gladyshev V. I. Lelikov A. I. Chikshov 《Radiation Physics and Chemistry》1998,52(1-6):425-427
Co-60 sources represent one of the key factors in industrial radiation processing and applications such as sterilization of disposable products and food preservation. Design of the sources being currently used in wet gamma irradiators can be improved with the purpose of increasing the source corrosion stability and mechanical integrity during use. This paper describes the proposed new design of Co-60 source for wet gamma irradiators. As a result of changes in capsule material and some dimensions, product quality and reliability can be improved with no additional cost for end user. 相似文献