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991.
992.
水和甲醇存在下MAMS的消失反应动力学研究 总被引:1,自引:0,他引:1
通过实验研究了甲基丙烯酰胺硫酸盐(MAMS)与甲醇、水进行反应的动力学,并对该反应的机理进行了探讨。 相似文献
993.
994.
膜法富氧技术及其应用研究 总被引:12,自引:0,他引:12
介绍了作者在膜法富氧技术方面的研究进展,并将膜法与其他制氧方法进行了比较,最后讨论了膜法富氧技术目前的有关应用,着重研究了膜法富氧在有色金属冶炼,硅酸盐窑炉,化铁炉,加热炉,医疗保健和柴油机增氧等方面的典型应用。 相似文献
995.
Herein we report a new and simple method that has been developed to prepare smart polymeric microgels consisting of temperature-sensitive cores with pH-sensitive shells. The microgels were obtained directly from one step seed polymerization of N-isopropylacrylamide and N,N-methylenebisacrylamide from water-soluble biopolymers containing carboxymethyl groups in supercritical carbon dioxide. The effect of initial concentration of initiator, crosslinker, and carboxymethyl starch (CMS) dose as well as reaction pressures on the yield and morphology of the resulting polymer were investigated. CMS and crosslinker worked effectively as surfactant to some extent. PNIPAM/CMS particles with diameters in 100 nm and narrow particle size distribution were produced in supercritical carbon dioxide, in high yield and in short reaction times. 相似文献
996.
Dajun Shen 《国际水》2013,38(4):484-496
China's rivers face major challenges arising from social and economic development, particularly associated with pollution and over-abstraction. Although these issues vary significantly across the country, China has adopted a national, unified approach to manage water resources in a river basin context. This paper assesses the legal and institutional arrangements for river basin management in terms of decentralization and centralization. It considers the appropriate roles for the different levels of government, including providing for participation and integration across these levels. It proposes strengthening institutional development and capacity building in the future. 相似文献
997.
998.
999.
In order to improve the electrochemical performance and thermal stability of Li1.05Co1/3Ni1/3Mn1/3O2 materials,Li1.05Co0.3Ni0.35Mn0.3M0.05O2(M=Ge,Sn)cathode materials were synthesized via co-precipitation method.The structure,electrochemical performance and thermal stability were characterized by X-ray diffraction(XRD),charge/discharge cycling,cyclic voltammetry(CV),electrochemical impedance spectroscopy(EIS)and differential scanning calorimetry(DSC).ESEM showed that Sn-doped and Ge-doped slightly increased the size of grains.XRD and CV showed that Sn-doped and Ge-doped powders were homogeneous and had the better layered structure than the bare one.Sn-doped and Ge-doped improved high rate discharge capacity and cycle-life performance.The reason of the better cycling performance of the doped one was the increasing of lithium-ion diffusion rate and charge transfer rate.Sn-doped and Ge-doped also improved the mateials thermal stability. 相似文献
1000.
Pressure relief to increase permeability significantly improves gas extraction efficiency from coal seams. In this paper we report results from simulations using FLAC3D code to analyze changes in coal displacement and stress after special drill slots were formed. We investigated the mechanism of pressure relief and permeability increase in a high-gas and low-permeability coal seam through the modeling of gas flow. This allows the development of the technology. Slotting across rock layers in the coal seam with a rotary type cutter was then applied in the field. The results show that pressure relief and permeability increases from slotting the coal seam can increase the transport and the fracture of the coal. This expands the range of pressure relief from the drilling and increases the exposed area of the seam. The total quantity of gas extracted from slotted bore holes was three times that seen with ordinary drilling. The concentration of gas extracted from the slotted drills was from two to three times that seen using ordinary drills. The gas flow was stable at 80%. Improved permeability and more efficient gas extraction are the result of the slotting. The roadway development rate is increased by 30–50% after gas drainage. This technology diminishes the lag between longwall production and roadway development and effectively prevents coal and gas outburst, which offers the prospect of broad application. 相似文献