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排序方式: 共有264条查询结果,搜索用时 304 毫秒
81.
在冰表面上硝酸氯和氯化氢反应的机理   总被引:3,自引:2,他引:3  
On the line of multi-molecule-formed transition state mechanism, reaction of ClONO2 with HCl on ice surface was investigated with model system by theoretical ab initio calculations. In the gas phase, the barrier of reaction of ClONO2 with HCl is 240.2kJ•mol-1at MP2HF/6-31G(d) level. The barriers drop substantially with the involvement of water molecules. The barrier of reaction of ClONO2 with 2H2O•HCl is 4.6kJ•mol-1 at the same theoretical level which suggests that the reaction of ClONO2 with HCl can occur readily on ice surface. The detailed account will be published in near future.  相似文献   
82.
利用水热法, 以硅胶为载体, 以Ti(SO4)2为钛源, NaCl为氯源制备了具有良好性能的硅胶负载氯掺杂二氧化钛(CTS)光催化剂, 考察了氯投加量、焙烧温度及钛硅比对光催化活性的影响. 结果表明, 氯投加量为15% (nCl/nTi)、钛硅物质的量比为3:1、焙烧温度为750 ℃时制备的CTS具有最佳的光催化活性, 其比表面积为60.8 m2·g-1. CTS中的硅胶除了作为载体, 还起到了促进锐钛矿二氧化钛的生成并抑制其向金红石相转变的作用; 氯掺杂二氧化钛(CT)经硅胶负载后, 其表面孔结构发生了变化, 并且热稳定性增加. 苯酚降解实验表明, 与CT相比, CTS以0.7740 g·g-1的二氧化钛含量具有更高的光催化活性.  相似文献   
83.
二氧化氯催化氧化处理含酚废水的研究   总被引:13,自引:0,他引:13  
以3种模拟的高浓度含酚废水为处理对象,在室温常压下,以二氧化氯为催化剂,在自制催化剂的作用下进行催化氧化分解酚类物质的研究,考察了PH,ClO2废水(体积比),反应时间,反应温度等对CODCr去除率的影响。实验表明该法能有效地降低含酸废水的CODCr,去除率达90%以上,是一种行之有效的含酚废水处理方法。  相似文献   
84.
Low-fluence XeCl laser etching of copper foils in a chlorine environment has been studied. The etch rate is fluence-dependent in the range 0.05–1.0 J cm?2 and is governed by the growth characteristics of the chloride layer formed in the interpulse period. Projection etching with good pattern reproduction and resolution for high-aspect-ratio features is demonstrated.  相似文献   
85.
We investigated desorption of chlorine atoms on Si (1 1 1)-(7 × 7) surfaces induced by hole injection from scanning tunneling microscope tips. The hole-induced desorption of chlorine atoms had a threshold bias voltage corresponding to the energy position of the S3 surface band originated in Si backbonds. The chlorine atom desorption rate was almost proportional to the square of the tunneling current. We have discussed possible mechanisms that two holes injected into Si surface states get localized at the backbonds of chlorinated Si adatoms, which induces the rupture of Cl-Si bonds to result in chlorine atom desorption.  相似文献   
86.
Concern about pollutant formation and emissions continues to be a driving force for research in combustion chemistry. Important pollutants include nitrogen oxides (NOx), sulfur oxides (SOx), chlorine species, unburned or partly burned fuel components (e.g., UHC, aldehydes, CO), aromatic and polycyclic aromatic compounds, and aerosols (soot, alkaline aerosols). In this review, it is discussed how N, S, Cl, and K/Na species, typically present in small quantities, may affect the overall combustion process, as well as the formation or transformation of each other. Of special interest is their ability to sensitize or inhibit oxidation of fuel and CO, depending on the reaction conditions; the impact of S, Cl and K/Na on formation of NOx, PAH, and soot; and the interaction of sulfur, chlorine and alkali species, which may have significant implications for emissions of SO2, HCl, and aerosols.  相似文献   
87.
CIONO2与O(3P)的反应机理   总被引:1,自引:0,他引:1  
采用密度泛函方法B3LYP/6-31G^*研究了反应O(^3P)+ClONO2→ClO+NO3反应O(^3P)+ClONO2→O2+ClONO的反应机。该结果与大部分实验者的推论是一致的,对于后一反应,其两种反应途径的活化势垒较为相近,表明两种反应途径均是可能的。  相似文献   
88.
Seven compounds are formed in various amounts when a solution of cyclopropopyl phenyl propargyl alcohol and trifluoromethylsulfenyl chloride in acetonitrile is exposed to UV light. The probable mechanism of formation and the mass spectral characterization of these compounds are described.  相似文献   
89.
Chlorinated-Indium Tin Oxide (Cl-ITO) has been found to have higher work function than the pristine ITO. When used as anode for polymer light-emitting diodes (PLEDs) with deep blue emitting β-phase poly(9,9-di-n-octylfluorene) (β-PFO) as the emitting layer, it allows hole injection without barrier. However, the presence of chlorine free radical on the surface of Cl-ITO leads to an exciton quenching effect. The surface modification on anode by dipping into 1% ammonium (NH4OH) aqueous solution to remove free chlorine radicals on surface can enhance device performance significantly. The single layer device Cl-ITO (treated)/β-PFO/CsF/Al gives the maximum brightness 16773 cd/m2 and maximum luminance efficiency 2.40 cd/A, which are higher than those with untreated Cl-ITO, (2519; 0.27) and CFx treated ITO, (7800; 1.8) and PEDOT:PSS coated ITO, (12884; 1.43). The ease of the present anode treatment allows the one-layer-only device to be a promising candidate for practical application.  相似文献   
90.
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