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71.
A new-type UV light source(206 nm) was explored for the degradation of organic pollutants in wastewater for the first time.The degradation performances of triphenyltin chloride(TPTCl),dimethyl phthalate(DMP),as well as rhodamine B(RhB) were investigated.The results indicated that removal efficiency of 50 mg/L RhB,60 mg/L DMP and 120 mg/L TPTCl can reach 88.6%, 92.5%and 89.4%for 60 min,50 min and 75 min,respectively.By comparison of removal efficiency,we found 206 nm is superior to 253.7 nm UV in wastewat... 相似文献
72.
KOKOT Serge 《高等学校化学研究》2009,25(2)
Differential pulse stripping voltammetry method(DPSV) was applied to the determination of three herbicides,ametryn,cyanatryn,and dimethametryn.It was found that their voltammograms overlapped strongly,and it is difficult to determine these compounds individually from their mixtures.With the aid of chemometrics,classical least squares(CLS),principal component regression(PCR) and partial least squares(PLS),voltammogram resolution and quantitative analysis of the synthetic mixtures of the three compounds were successfully performed.The proposed method was also applied to the analysis of some real samples with satisfactory results. 相似文献
73.
74.
耐硫催化剂上合成混合醇的研究 总被引:2,自引:1,他引:2
通过改进制备方法和添加助剂,用浸渍-热分解法制得了具有高活性和高选择性的MoS2-K-C型耐硫低碳混合醇催化剂。在8.0-11.0MPa,290-340℃,6000-12000h^-1,H2 S 浓度为100ppm 左右的条件下,在直流反应器中对催化剂进行了性能测试,结果表明,醇得率为0.14-0.47gROH(gcat·h)^-1,选择性为89-98%。同时,考察了操作条件对催化剂性能的影响。1042h的试验,证明催化剂具有很好的稳定性。 相似文献
75.
本文提出了一个硫酸中间盐子循环用以代替分解水制氢的KNO_3-I_2混合循环中的电解反应,从而使原混合循环变为一个纯热化学循环。 相似文献
76.
Fandong Meng Genhui Xu Baowei Wang Xinbin Ma. School of Chemical Engineering Technology Tianjin University Tianjin China . Luoyang Petrochemical Engineering Corporation Luoyang ChinaManuscript received March revised Apr 《天然气化学杂志》2002,(Z1)
This article describes a process for the synthesis of diethyl oxalate by a coupling reaction of carbon monoxide, catalyzed by palladium in the presence of ethyl nitrite. The kinetics and mechanism of the coupling and regeneration reaction are also discussed. This paper presents the results of a scale-up test of the catalyst and the process based on an a priori computer simulation. 相似文献
77.
Adaptation of Cu/ZnO/Al_2O_3 to Temperature Change in Methanol Synthesis from CO_2 Hydrogenation 下载免费PDF全文
Jialin Tao Ki-Won Jun Kyu-Wan Lee. Chemical Technology Lab. Korea Research Institute of Chemical Technology P.O. Box Yusong Taejon - Korea. Chengdu Institute of Organic Chemistry Chinese Academy of Sciences Chengdu ChinaManus 《天然气化学杂志》2002,(Z1)
The induction behavior in CO2 hydrogenation was studied by varying the reaction temperature to investigate the adaptation of the Cu/ZnO/Al2O3 catalyst to the temperature change. The results indicated that a used catalyst had a tendency to keep the last running state in new reaction conditions for MeOH formation, and that this tendency was related to the difference in Cu/Cun+ ratio caused by CO2 and CO produced at different reaction temperatures. However, the reverse water-gas shift reaction (RWGS) induced at four temperatures was completely different from that of methanol synthesis. It implied that the two so-called competitive reactions in CO2+H2, RWGS and methanol synthesis, have different active centers. 相似文献
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79.
DaXinSHI YaQingFENG ShunHeZHONG 《中国化学快报》2005,16(5):685-687
Photoinduced synthesis of CO2 and CH4 was investigated using a batch reaction system on several photoactive materials supported on silicon dioxide. Single semiconductor showed higher selectivity to C1 compounds. The production of C2-C3 oxygenates took place preferentially on composite semiconductor photocatalysts. In particular, it was found that acetone was the primary product over Cu/CdS-TiO2/SiO2. 相似文献
80.
In this paper, a novel exact fixed-node quantum Monte Carlo (EFNQMC) algorithm was proposed, which is a self-optimizing and self-improving procedure. In contrast to the previous EFN-QMC method, the importance function of this method is optimized synchronistically in the diffusion procedure, but not be-fore beginning the EFNQMC computation. In order to optimize the importance function, the improved steepest descent tech-nique is used, in which the step size is automatically adjustable.The procedure is quasi-Newton type and converges super linear-ly. The present method also uses a novel trial function, which has correct electron-electron and electron-nucleus cusp condi-tious. The novel EFNQMC algorithm and the novel trial func-tion are employed to calculate the energies of 1 ^1A1 state of CH2, ^1Ag state of Cs and the ground-states of H2, LiH, Li2 and H2O. 相似文献