CO_2 capture from binary mixture via forming hydrate with the help of tetra-n-butyl ammonium bromide

Hydrate formation rate and separation effect on the capture of CO2 from binary mixture via forming hydrate with 5 wt% tetra-n-butyl ammonium bromide （TBAB） solution were studied. The results showed that the induction time was 5 min, and the hydrate formation process finished in 1 h at 4.5 ℃ and 4.01 MPa. The hydrate formation rate constant reached the maximum of 1.84× 10^-7 molZ/（s.J） with the feed pressure of 7.30 MPa. The CO2 recovery was about 45 % in the feed pressure range from 4.30 to 7.30 MPa. Under the feed pressure of 4.30 MPa, the maximum separation factor and CO2 concentration in hydrate phase were 7.3 and 38.2 mol%, respectively. The results demonstrated that TBAB accelerated hydrate formation and enriched CO2 in hydrate phase under the gentle condition.

Highly efficient solvent-free synthesis of quinazolin-4(3H)-ones and 2,3-dihydroquinazolin-4(1H)-ones using tetrabutylammonium bromide as novel ionic liquid catalyst

A simple and efficient procedure for the synthesis of 2-arylquinazolin-4（3H）-ones has been developed through cyclocondensation of 2-aminobenzamide with aromatic aldehydes using tetrabutylammonium bromide（TBAB） as novel neutral ionic liquid catalyst in the presence of copper（Ⅱ） chloride（CuCl;） as oxidizing agent under solvent-free conditions at 100℃.In the absence of CuCl;and under a nitrogen atmosphere,the unoxidized intermediates,2-aryl-2,3-dihydroquinazolin-4（1H）-ones,were isolated. Treatment of these intermediates with CuCl;in TBAB media gave the oxidized products 2-arylquinazolin-4（3H）-ones.On the other hand,cyclocondensation of 2-aminobenzamide with aromatic aldehydes in TBAB under microwave irradiation directly gave 2- arylquinazolin-4（3H）-ones.

The effect of cations(NH_4^+,Na^+,K^+,and Ca^(2+)) on chemical deactivation of commercial SCR catalyst by bromides

Alkali and alkaline‐earth metals from fly ash have a significant deactivation effect on catalysts used for selective catalytic reduction of NOx by NH3(NH3‐SCR).Bromides are considered effective additives to improve Hg0 oxidation on SCR catalysts.In this work,the effects of different bromides(NH4Br,NaBr,KBr,and CaBr2)on a commercial V2O5‐WO3/TiO2 catalyst were studied.NOx conversion decreased significantly over the KBr‐poisoned catalyst(denoted as L‐KBr),while that over NaBr‐and CaBr2‐poisoned catalysts(denoted as L‐NaBr and L‐CaBr,respectivity)decreased to a lesser extent compared with the fresh sample.Poor N2 selectivity was observed over L‐NaBr,L‐KBr and L‐CaBr catalysts.The decrease in the ratio of chemisorbed oxygen to total surface oxygen(Oα/(Oα+Oβ+Ow)),reducibility and surface acidity might contribute to the poor activity and N2 selectivity over L‐KBr catalyst.The increased Oαratio was conducive to the enhanced reducibility of L‐CaBr.Combined with enhanced surface acidity,this might offset the negative effect of the loss of active sites by CaBr2 covering.The overoxidation of NH3 and poor N2 selectivity in NH3 oxidation should retard the SCR activity at high temperatures over L‐CaBr catalyst.The increased basicity might contribute to increased NOx adsorption on L‐KBr and L‐CaBr catalysts.A correlation between the acid‐basic and redox properties of bromide‐poisoned catalysts and their catalytic properties is established.

1,3-二(2′-氨基亚乙基)-2-甲基咪唑溴盐与环氧树脂E-51的固化工艺

通过咪唑环上的季铵化反应,制备一种适用于环氧树脂的双氨基咪唑类离子液体固化剂1,3-二(2′-氨基亚乙基)-2-甲基咪唑溴盐(DAIL)。以环氧树脂E-51作为基体树脂,深入研究DAIL作为固化剂的固化工艺条件和固化物的性能。结果表明,DAIL可作为环氧树脂E-51的中温固化剂使用,二者的最佳质量比为DAIL∶E-51=20∶100,最佳固化温度范围为74~105℃,后固化温度为162℃,固化后的浇注体样条抗拉强度为159 MPa,弹性模量为2281 MPa,断裂伸长率为12.8%,热分解温度为424.4℃。DMA分析表明DAIL/E-51浇注体最大损耗因子tanδ为0.56,玻璃转化温度θg为83℃,对应的贮存模量E为290 MPa,交联密度为30149 mol·m^(-3)。该结果为高力学性能中温环氧树脂固化剂的使用提供了重要实验依据。

Bromophenacyl bromide,a phospholipase A_2 inhibitor attenuates chemically induced gastroduodenal ulcers in rats

AIM: To study the effect of bromophenacyl bromide (BPB), a phospholipase A2 inhibitor on gastric secretion and to protect chemically induced gastric and duodenal ulcers in rats. METHODS: Acid secretion studies were undertaken in pylorus-ligated rats with BPB treatment (0, 5, 15 and 45 mg/kg). Gastric and duodenal lesions in the rats were induced by ethanol and cysteamine respectively. The levels of gastric wall mucus, nonprotein sulfhydryls (NP- SH) and myeloperoxidase (MPO) were also measured in the glandular stomach of rats following ethanol induced gastric lesions. RESULTS: BPB produced a dose-dependent inhibition of gastric acid secretion and acidity in rats. Pretreatment with BPB significantly attenuated the formation of etha- nol induced gastric lesion. BPB also protected intestinal mucosa against cysteamine-induced duodenal ulcers. The antiulcer activity of BPB was associated with signifi- cant inhibition of ethanol-induced depletion of gastric wall mucus, NP-SH and MPO. These findings pointed towards the mediation of sulfhydryls in BPB induced gas- trointestinal cytoprotection. CONCLUSION: BPB possesses significant antiulcer and cytoprotective activity against experimentally induced gastroduodenal lesions.

Convenient one-pot synthesis of functionalized (E)-2-arylvinyl bromides from (E)-4-(2-bromovinyl)phenyl acetate

A convenient one-pot synthesis of functionalized （E）-2-arylvinyl bromides was achieved by microwave-induced deacetylation and subsequent acylation using dicyclohexyl carbodiimide （DCC） and dimethylamino-pyridine （DMAP） at room temperature from （E）-4-（2-bromovinyl）phenyl acetate.

Organomontmorillonites Modified with 2-Methacryloyloxy Ethyl Alkyl Dimethyl Ammonium Bromide

Organomontmorillonites （organo-MMT） were synthesized by means of montmorillonites （MMT） modified with a series of 2-methacryloyloxy ethyl alkyl dimethyl ammonium bromide （MAAB） having different alkyl chain lengths as cationic surfactants through a cationic exchanging reaction, and were characterized by FTIR, TG, elemental analysis, and XRD. The microenvironment of the organic interlayer such as the orientation and arrangement of the alkyl chains of MAAB, as well as the properties of nanocomposite hydrogels, were also investigated. The amount of organic components absorbed on interlayer and the basal spacing of organo-MMT both increase with the increasing of alkyl length of MAAB. When carbon number of alkyl chain is in the region of 8 to 14, the alkyl chains between layers would adopt a disordered gauche conformation; while the carbon number is 16, an ordered all-trans conformation with a vertical orientation would be found together with the disordered gauche conformation according to the results of XRD and FTIR. Due to the difference of microenvironment of organic interlayer, the Young＇s moduli of the nanocomposite hydrogels increased as the alkyl chains of MAAB became longer.

Novel Approach to Characterization of Rare Earth Complexation with 1, 5-Bis(2-Hydroxy-5-Chlorphenyl)-3-Cyanoformazan in Presence of Cetyltrimethylammonium Bromide

The ternary interaction of 1, 5 bis(2 hydroxy 5 chlorphenyl) 3 cyanoformazan (HCPCF) with cetyltrimethylammonium bromide (CTAB) and rare earths (RE: Yb, Dy, Er and Eu) was investigated at pH 9.84 by the microsurface adsorption spectral correction technique (MSASC). The aggregation of HCPCF on CTAB obeys the Langmuir isothermal adsorption and the interaction of RE with the HCPCF CTAB aggregate was first found to accord with the monolayer binding. The effects of temperature and ionic strength of solution on the aggregations were made. The binary aggregate and the ternary complex were characterized.

Synthesis, Characterization and X-ray Crystal Structure of 2-Benzyl-7-butoxyl-9-isobutyl-1-methyl-β-carboline Bromide

2-Benzyl-7-butoxyl-9-isobutyl-1-methyl-β-carboline bromide（H-2-65） was synthesized by the reaction of Harmine with 1-iodobutane via N9-alkylation, demethyl and N2-quaternarization to obtain the new compound. The results demonstrate that H-2-65 has more remarkable anticancer activities in vitro. The results of 1H NMR, 13 C NMR, DEPT, g COSY, g HSQC, g HMBC, MS, single-crystal X-ray diffraction and elemental analysis showed that the title compound crystallizes in the triclinic system, space group P1 with a = 9.545（5）, b = 11.724（5）, c = 11.839（6） , α = 77.530（6）, β = 87.169（6）, γ = 72.823（5）o, Z = 2, V = 1235.8（10）3, Dc = 1.294 g·cm-3, F（000） = 504, the final R = 0.0453, wR = 0.1262 and S = 1.044.

FLOCCULATION OF KAOLIN SUSPENSION OF ISOTACTIC-AND ATACTIC-POLY(N-PROPYL-2-VINYLPYRIDINIUM BROMIDE)

Isotactic-and atactic-poly(N-propyl-2-vinylpyridinium bromide)QIP2VP and QAP2VP were used asflocculants for kaolin suspension.The effects of their molecular structure of floeculation were studied.Theresults are as follows:(1)The ability of flocculation of QAP2VP is better than that of QIP2VP.(2)The flocculating efficiency of QAP2VP,but not QIP2VP,increased as the molecular weight in-creased.(3)In the range of lower degree of quaternization,the efficiency of flocculation increased as thedegree of quaternization of flocculants decreased.(4)An abnormal phenomenon,which is considered as the“homocharge stabilization”,was discoveredat a certain concentration of flocculants.(5)An equation of the relationship among the experimental parametars,such as sedimentation rate,sedimentation volume and turbidity,was derived.

沉积参数对铯铅溴钙钛矿薄膜中CsPb_(2)Br_(5)相结构演变和发光特性的影响

基于化学气相沉积(CVD)法制备的铯铅溴钙钛矿薄膜具有优异的光电特性,然而薄膜通常存在CsPbBr_(3)和CsPb_(2)Br_(5)两个不同的相结构区域。本文通过CVD法制备了铯铅溴钙钛矿薄膜,并利用X射线衍射(XRD)、扫描电镜(SEM)、电子能谱仪(EDS)及荧光光谱仪研究了反应气压与N_(2)流量对其中的CsPb_(2)Br_(5)相结构的影响。实验结果表明,反应气压的变化对CsPb_(2)Br_(5)相结构无影响;与此不同,随着N_(2)流量的减少,薄膜中部分CsPb_(2)Br_(5)相结构逐渐转变为CsPbBr_(3)相结构,其发光也由以~630 nm为主的宽带发射转变为以~530 nm为主的窄带发射。实验表明,N2流量是调控CsPb_(2)Br_(5)相结构和发光特性的有效手段。

氨基酸和DTAC对CO_(2)水合分离动力学影响

促进剂对CO_(2)水合分离动力学影响较大。为了明确不同浓度的甲硫氨酸、色氨酸、十二烷基三甲基氯化铵(DTAC)等促进剂对水泥厂烟气水合物生成动力学和形态的影响,在温度278.15K、初始压力3.60MPa下使用间歇式反应釜,高、低转速组合搅拌的方法,分别与四丁基溴化铵(TBAB)复配,以诱导时间、载气量、t90、CO_(2)回收率和分离因子为指标进行了实验研究。结果表明:甲硫氨酸有效提高了烟气中CO_(2)分离效率,分离因子达到19.86;色氨酸在促进烟气水合物成核方面优势突出,当浓度为0.1%(质量分数,下同)时诱导时间较纯TBAB溶液下降了60.7%,但CO_(2)载气量较低;DTAC体系下液相内部生成了大量分散的颗粒状水合物,消除了窒息效应,但降低了分离效率。另外,TBAB浓度升高后诱导时间骤降至20~30s,但对其他指标影响较小。综上,5%TBAB+0.2%甲硫氨酸促进性能平衡优良,捕集的CO_(2)浓度达到80.21%,且具有用量较少、可生物降解、分解无泡沫产生等优势,是最佳复配方案,可为工业化应用提供理论参考。

菲在TiO_2催化下的光降解研究

以汞灯为光源 ,TiO2 为催化剂 ,对菲的光催化降解途径进行了研究 .将水溶性极小的菲预先吸附到TiO2 上之后 ,菲可以在紫外线的照射下发生快速、完全的矿化 .通过GC MS手段检测到一些中间产物 ,给出了菲光催化降解的详细途径 .另外 ,研究了菲在表面活性剂十六烷基三甲基溴化铵 (HTAB)的助溶下TiO2 催化的光降解过程 ,探讨了表面活性剂的浓度和溶液 pH值对反应速率的影响 .

分光光度法研究IrI_6^(2-)与常见金属元素的浮选分离

用分光光度法研究碘化钾-四丁基溴化铵体系浮选分离IrI2-的行为及其与常见离子分离的条件.实验结果表明,控制pH1～2.8,能使IrI26-与Sn(Ⅳ),Co(Ⅱ),Mn(Ⅱ),Fe(Ⅱ),Zn(Ⅱ),Al(Ⅲ),Cr(Ⅲ),Ni(Ⅱ)和Mg(Ⅱ)分离.

新试剂1-(2-羟基-3,5-二硝基苯基)-3-[4-(苯基偶氮)苯基]-三氮烯的合成及与季铵盐型阳离子表面活性剂的显色反应

合成了新试剂1-(2-羟基-3,5-二硝基苯基)-3-[4(苯基偶氮)苯基]-三氮烯(HDNPAPT),研究了该试剂在NaOH介质中与阳离子表面活性剂漠化十六烷基三甲铵(CTMAB)、溴化十六烷基吡啶(CPB)、溴化十二烷基二苄铰(DDMBAB)形成1:3的紫红色离子缔合物显色体系.测定了显色体系表面活性剂的临界胶束浓度、表观摩尔吸光系数ε_(max)、符合比尔定律的范围.探讨了微量阳离子表面活性剂CMTAB、CPB和DDMBAB的测定方法,结果满意.

阳离子表面活性剂溴代十六烷基吡啶胶束对2,4-二硝基氯苯水解反应的影响

阳离子表面活性剂溴代十六烷基吡啶（CPB）胶束对水中OH-和2，4-二硝基氯苯的反应有催化作用．随CPB浓度的增大，反应速率常数开始时迅速增大，然后趋于常数．OH-浓度的增大使胶束催化水解的二级速率常数减小．CPB胶束对此反应的速率提高作用比十六烷基三甲基溴化扶胶束更有效．对这两种胶束催化作用的差异进行了讨论．

改性沸石对2,4-二氯苯酚的吸附性能研究

采用溴化十六烷基三甲铵(HDTMAB)制备了改性沸石.并研究了其吸附性能的影响因素,包括HDTMAB的加入量、有机污染 物的初始质量浓度、溶液的pH值等,绘制了改性沸石吸附2,4-DCP的吸附等温线并得到了饱和吸附容量。结果表明,改性沸石对2,4 二氯苯酚(2,4-DCP)具有很好的吸附效果,实验条件下对2,4-DCP的去除率可达90％以上。

碳酸二甲酯作甲基化试剂催化合成2-甲硫基苯并噻唑

研究了在四丁基溴化铵(Bu4NBr)与K2CO3催化下,2-巯基苯并噻唑(MBT)与碳酸二甲酯(DMC)合成标题化合物的反应。考察了反应的物料配比、反应时间、反应温度及碱试剂种类和用量对反应的影响。得出甲基化反应最佳配比为:n(MBT)∶n(DMC)∶n(K2CO3)∶n(Bu4NBr)=1∶18∶1.5∶0.2,90℃下反应3h,收率76.4%。副产物为N-甲基化物,讨论了生成副产物的可能机理。

溴离子在PbO_2电极上电氧化的研究

通过溴离子在 Pb O2 电极上阳极极化曲线及电流效率的测定 ,探讨了溴离子氧化的反应机理和电解条件 .研究发现 ,溴离子的电氧化为一级反应 ;在电极电势 1 .1 6～ 1 .2 6V范围内 ,其表观活化能为 8.5 3～8.81 k J/ mol.在 p H=2 .0～ 1 0 .2范围内 ,溴离子在 Pb O2 电极上氧化的电流效率变化较小 ,但电流效率随温度的升高略有下降 ,随溴离子浓度的升高电流效率先升高 ,达到一定浓度后趋于不变 .

2′,3′-双脱氧尿苷的合成

以价廉易得的尿苷为原料,经原甲酸三甲酯选择性地保护2′和3′位的羟基,得到的2′,3′-O-甲氧甲叉尿苷与乙酰溴反应制得溴代核苷衍生物,再经脱溴、脱乙酰氧基成烯,催化氢化还原,碱性条件下醇解得到2′,3′-双脱氧尿苷.