A novel supramolecular graft copolymer via cucurbit[8]uril-based complexation and its self-assembly

A novel supramolecular graft copolymer（SGP） composed of viologen-containing copolymer（P（DMA-co-diEV）） as the main chain and Np ended PNIPAM（Np-PN1PAm） as the grafts is prepared（DMA:N,N- dimethylacryamide,diEV:ethylviologen dimer,Np:naphthalene,PNIPAM:poly（N-isopropylacrylamide））. The grafting is based on the triple complexation among a host of cucurbit[8]uril（CB[8]）and two guests of diEV and Np,which is characterized by UV-vis spectra and ITC.Temperature sensitive property of PNIPAm moiety allows SGP to self-assemble into non-covalently connected micelle（NCCM） at high temperature. The micelles are sensitive to reducing agents,for example Na₂S₂O₃,which breaks the current inclusion complex pair and induces aggregation.     

α,β-聚（N-2-羟乙基）-L-天冬酰胺的合成及对Pb2+和Cu2+螯合性能的研究

以天冬氨酸热缩聚得到的聚琥珀酰亚胺(PSI)为原料,与乙醇胺通过氨解开环反应,合成了聚天冬氨酸的接枝衍生物α,β-聚(N-2-羟乙基)-L-天冬酰胺(PHEA)。用红外光谱表征了产物的结构;用凝胶色谱测定了分子量分布。研究了PHEA用量、pH值和金属离子初始浓度等对Pb2+和Cu2+去除率的影响,在pH=5.0时,Pb2+的最大去除率为92.48%;在pH=4.5时,Cu2+的最大去除率为89.34%。Pb2+和Cu2+最大静态螯合量分别为25.64mg/g和17.68mg/g。通过XPS分析得知,PHEA与Pb2+螯合时,氮原子和氧原子参与了反应;与Cu2+螯合时,主要是氧原子参与反应。     

硝酸铵废水电去离子深度处理及资源化利用

针对目前用电渗析法处理硝酸铵废水的方法,提出以电去离子法作为硝酸铵废水的深度处理方法,弥补了现有电渗析处理的不足,达到硝酸铵废水处理系统零排放,硝酸铵和水全部回收,真正做到废水资源化利用。这种改良型电渗析处理方法,除可使高浓度水中氨氮质量浓度达10%以外,还可保证系统出水中氨氮浓度不大于1mg/L。     

高效液相色谱-串联质谱法检测食品中6种邻苯二甲酸酯

建立了食品中邻苯二甲酸二丁酯(DBP)、邻苯二甲酸丁基苄基酯(BBP)、邻苯二甲酸二已酯(DEHP)、邻苯二甲酸二正苄酯(DNOP)、邻苯二甲酸二异壬酯(DINP)、邻苯二甲酸二异癸酯(DIDP)6种邻苯二甲酸酯的高效液相色谱-串联质谱检测方法。试样用正己烷∶甲基叔丁基醚∶乙腈(体积比为50∶45∶5)提取并冷冻离心去除脂肪,收集溶剂层并挥干,加入0.5g乙二胺-N-丙基硅烷(PSA)并用2mL乙腈溶液混匀,冷冻离心后过膜备用。优化分离与检测的最佳条件,采用电喷雾正离子电离(ESI+)模式和多离子反应监控(MRM)模式,外标法进行定量。该方法中DBP、BBP、DEHP、DNOP在0.1～3.0mg/L之间,DINP和DIDP在1.0～30.0mg/L之间的线性相关系数R2>0.995;检测限分别为:DBP 0.02mg/L,BBP、DEHP和DNOP 0.005mg/L,DINP和DIDP 0.10mg/L。在添加水平为0.2、0.5、1.0mg/kg时的平均加标回收率和相对标准偏差范围符合食品检测要求。该方法简便、灵敏、精确,适用于检测食品中6种邻苯二甲酸酯残留。     

GC-MS法快速测定食品接触材料油墨中16种多环芳烃

以正己烷超声提取,弗罗里硅土固相萃取柱净化,以正己烷-二氯甲烷溶液(体积比1:1)洗脱,用GC-MS联用仪SIM模式外标法定量测定食品接触材料油墨中16种多环芳烃.在优化条件下,16种多环芳烃的浓度在0.1～4.0 μg/mL范围内与色谱峰面积呈良好的线性关系,线性相关系数大于0.995,检出限为0.12～3.24 ng/L.加标回收率为77.24％～ 104.76％,测定结果的相对标准偏差为1.05％～1.69％(n=6).该方法适用于食品接触材料油墨中PAHs的日常检测.     

油楠树脂油化学成分的研究

采用毛细管气相色谱-质谱(CGC-MS)联用技术对油楠树脂油的化学成分进行研究,共分离出42个峰,并确认了其中39种成分,占总油量的94.31%。分离出的主要成分为蓖麻油酸(17.91%);7,7,8,8-四甲基二环[4.2.0]辛烷-1(6),3-二烯-2,5-二酮(7.60%);1,2-二乙基-3,4-二甲基-苯(6.70%);1,2,6,6-四甲基-1,3-环己二烯(5.35%);n-棕榈酸(4.47%);1,3,4-三甲基-3-环己烯-1-甲醛(4.17%)。     

Higher alcohol synthesis over Cu-Fe composite oxides with high selectivity to C2+OH

Cu-Fe composite oxides were prepared by co-precipitation method and tested for higher alcohol synthesis from syngas. The selectivity to C2+OH and C6+OH in alcohol distribution was very high while the methane product fraction in hydrocarbon distribution was rather low, demonstrating a promising potential in higher alcohols synthesis from syngas. The distribution of alcohols and hydrocarbons approximately obeyed Anderson-Schulz-Flory distribution with similar chain growth probability, indicating alcohols and hydrocarbons derived from the same intermediates. The effects of Cu/Fe molar ratio, reaction temperature and gas hourly space velocity (GHSV) on catalytic performance were studied in detail. The sample with a Cu/Fe molar ratio of 10/1 exhibited the best catalytic performance. Higher reaction temperature accelerated water-gas-shift reaction and led to lower total alcohols selectivity. GHSV showed great effect on catalytic performance and higher GHSV increased the total alcohol selectivity, indicating there existed visible dehydration reaction of alcohol into hydrocarbon.     

胆碱类低共熔溶剂的物性及应用

作为一种新型的离子液体,胆碱类低共熔溶剂具有相比于其他离子液体更为突出的特点,如低毒、生物可降解、价格低廉等,这些特点使得此类离子液体在绿色化学和工程化学中受到越来越多的关注。本文分析了胆碱类低共熔溶剂的凝固点、熔点、溶解度、黏度、表面张力、电导率等物性随温度、组成、水分等因素的变化及理论预测模型,并介绍了胆碱类低共熔溶剂在润滑、功能材料制备、电化学、有机合成及生物质催化转化等方面的潜在应用。最后就胆碱类低共熔溶剂研究及应用中存在的问题及难点对其前景做出展望。     

Electrogenerated Fe(I) Porphyrins: Efficient Electrocatalysts for Reductive Dechlorination of DDT in N,N′‐Dimethylformamide

Two iron(I) porphyrins were electrogenerated and then utilized as catalysts for the reductive dechlorination of 1,1‐bis(4‐chlorophenyl)‐2,2,2‐trichloroethane (DDT) in N,N′‐dimethylformamide. No reaction is observed between DDT and the Fe(III) or Fe(II) forms of the porphyrin, but the electrogenerated Fe(I) porphyrin efficiently catalyzes the electroreduction of DDT to give (1,1‐bis(4‐chlorophenyl)‐2,2‐dichloroethane) DDD, (1,1‐bis(4‐chlorophenyl)‐2,2‐dichloroethylene) DDE and (1,1‐bis(4‐chlorophenyl)‐2‐dichloroethane) DDMU as determined by GC‐MS analysis. The reductive dechlorination was monitored by electrochemistry, controlled potential electrolysis and spectroelectrochemistry and a mechanism for the reaction involving the reduced porphyrins and DDT is proposed. Comparisons are also made between the catalytic properties of metalloporphyrins containing iron, cobalt and manganese central metal ions under the same solution conditions.     

Ab initio study of mechanism of forming a spiro-ge-heterocyclic ring compound

The mechanism of cycloaddition reaction between singlet state dichloromethylenegermene (Cl₂C=Ge:) and ethene has been investigated with the CCSD(T)//B3LYP/6-31G* method. From the potential energy profile, it could be predicted that the reaction has one dominant reaction channel. The reaction rule presented is that the 4p unoccupied orbital of Ge in dichloromethylenegermene and the π orbital of ethene forming a π → p donor–acceptor bond resulting in the formation of a three-membered ring intermediate. Ring-enlargement effect make the three-membered ring intermediate isomerizes to a four-membered ring germylidene. Because the 4p unoccupied orbital of Ge atom in the four-membered ring germylidene and the π orbital of ethene form a π → p donor–acceptor bond, the four-membered ring germylidene further combines with ethene to form another intermediate. Because the Ge atom in the intermediate happens sp ³ hybridization after transition state, the intermediate isomerizes to a spiro-Ge-heterocyclic ring compound.