低共熔溶剂体系提取中药渣中肉桂醛

筛选适合的低共熔溶剂(DES)对中药渣疏水性功效成分进行高效提取对提高中药固废物的资源化利用效率有着重要的意义。采用微波辅助低共熔溶剂法对肉桂枝中药渣原料中的肉桂醛进行提取，考察低共熔溶剂类别、固液比、提取时间、摩尔比、提取温度等因素对肉桂醛提取率的影响。结果表明：氯化胆碱与乙二醇组成的DES体系中，在氯化胆碱与乙二醇摩尔比为1∶6、固液质量体积比1∶60、提取温度100℃、反应时间90 min的较优条件下肉桂醛的提取率可达到12.64 mg/g,相比传统甲醇提取法提取率增加了45.45%。中性DES相比酸性DES对功效成分的稳定性和提取效率都具有较佳的效果。氯化胆碱和乙二醇中性DES有益于中药渣功效成分的提取和纯化，具有较大的发展潜力。     

低共熔溶剂在乙腈-水体系分离中的应用

分别以乙二醇、氯化胆碱/乙二醇(摩尔比1∶2,DES1)、氯化胆碱/乙醇酸(摩尔比1∶3,DES2)低共熔溶剂为萃取剂,设计萃取精馏和萃取隔壁塔流程,模拟分离乙腈和水形成的共沸体系。使用灵敏度分析对上述流程分别进行了参数优化。结果表明,与乙二醇萃取精馏工艺相比,使用低共熔溶剂DES1不能有效降低能耗和费用;低共熔溶剂DES2用量降低52. 5%,能耗降低81. 9%,操作费用降低12%,年度总费用(TAC)降低53. 8%;采用隔壁塔萃取精馏工艺后,一定程度上都能节能减耗。DES2作为萃取剂的萃取精馏工艺为最优工艺,节能优势明显。     

LTTMS混合物在乙醇-水体系分离中的应用

分别乙二醇和两种低共熔溶剂(氯化胆碱/乙二醇(摩尔比1∶2)、氯化胆碱/乙醇酸(摩尔比1∶3))为萃取剂,设计萃取精馏和隔壁塔萃取精馏流程,模拟分离乙醇和水形成的共沸体系。使用灵敏度分析对上述流程分别进行了参数优化。在优化的基础上,进行了年度费用(TAC)计算。结果表明:采用乙二醇和低共熔溶剂为萃取剂的萃取精馏和隔壁塔萃取精馏均能实现乙醇-水的分离;年度费用结果表明采用氯化胆碱/乙二醇(摩尔比1∶2)的隔壁塔萃取精馏费用最低,为最优工艺。     

绿色低共熔溶剂提取野菊花中黄酮类化合物

研究氯化胆碱低共熔溶剂(DES)提取野菊花中的总黄酮、总槲皮素和槲皮苷.首先,合成了4种性能优异的DES,并对其物理性质进行表征.其次,以提取效果最好的氯化胆碱/尿素DES为溶剂,通过改变单一变量优化提取效果,在含水量30％、提取时间45 min、固液比1:50(g:mL,下同)、提取温度60℃的条件下,总黄酮、总槲皮...     

低共熔溶剂分离异丙醇-水体系的研究

分别以乙二醇和氯化胆碱/乙二醇(摩尔比1∶2)低共熔溶剂为萃取剂,设计萃取精馏和隔壁塔萃取精馏流程,模拟分离异丙醇和水形成的共沸体系。使用Aspen Plus中Sensitivity对2种流程进行参数优化。结果表明:与乙二醇萃取精馏相比,低共熔溶剂用量减少32%,能耗降低8%,年度总费用(TAC)降低8.5%;采用隔壁塔萃取精馏,乙二醇为萃取剂时能耗降低12%,TAC降低9%;低共熔溶剂为萃取剂能耗降低12%,TAC降低15.2%。采用低共熔溶剂的萃取隔壁塔流程节能优势明显。     

离子液体[Bmim][NTf_2]对CO_2在碳酸二乙酯中溶解性能的强化

采用恒定容积法在温度范围308.15~328.15 K、压力范围0~3 MPa条件下测定了CO_2在碳酸二乙酯(DEC)、离子液体[Bmim][NTf_2]以及二者不同质量分数配比混合溶剂中的溶解度,并用COSMO-RS模型研究了离子液体的加入对DEC蒸气分压的影响。实验表明,在相同实验条件下CO_2在[Bmim][NTf_2]中的溶解度大于在DEC中的溶解度。[Bmim][NTf_2]的加入可强化CO_2在DEC中的溶解性能,在相同温度下CO_2在混合溶剂中的溶解度随[Bmim][NTf_2]质量分数增加而增大,在相同浓度的混合溶剂中CO_2的溶解度随温度升高而降低。COSMO-RS模型计算表明,DEC的蒸气分压下降的分数随混合溶剂中离子液体质量分数增加而增大,而对于相同质量分数配比的混合溶剂温度对DEC的蒸气分压影响较小。     

酸性低共熔溶剂的理化特性及其与虾青素溶解度的相关性研究

制备7种酸性低共熔溶剂(DES),在不同温度下系统测定低共熔溶剂的理化特性,评估了虾青素的溶解度,并与有机溶剂和离子液体进行比较,深入探讨虾青素溶解度与低共熔溶剂理化性质之间的关联性。结果表明,7种酸性低共熔溶剂具有低黏度和良好的热稳定性;虾青素在7种低共熔溶剂中的溶解效果均优于乙醇与离子液体三丁基辛基氯化膦,溶解能力最强的是DL-薄荷醇∶乙酸(MAA),可达(405.94±12.90) mg/100 g;低共熔溶剂的密度、黏度和偶极性/极化率3个性质与虾青素溶解能力密切相关,相关系数分别为0.99、-0.85和0.83,这为选择和设计提取天然类胡萝卜素的溶剂及其应用提供了理论指导。     

三元低共熔离子液体中CO_2的吸收（英文）

由N,N-二甲基乙酰胺、氯化胆碱、乙二醇或丙三醇以不同的摩尔比(1:1:3,1:1:4)合成了一系列三元低共熔离子液体(nDMA:nCC:nethylene glycol=1:1:3,1:1:4,nDMA:nCC:nglycerol=1:1:3,1:1:4)。在293.15~323.15 K温度下,间隔10℃,0~600.0 k Pa压力范围内,用等温饱和法测量了CO2在三元体系中的溶解度。CO2在体系中的溶解度随压力增大呈线性增大趋势,随温度升高而减小。计算了亨利常数,结果表明,CO2在由N,N-二甲基乙酰胺,氯化胆碱,乙二醇以摩尔比1:1:3合成的三元体系,温度为293.15 K下,亨利常数最小,最小值为2.174 MPa·kg·mol-1。报道了关于CO2吸收的热动力学性质,包括焓变、熵变、Gibbs自由能变。其中,焓变为负值,说明此吸收为放热过程。     

低共熔溶剂中合成5-亚苄基巴比妥酸衍生物

低共熔溶剂是一种新型绿色溶剂,可以作为大多数有机反应的溶剂,同时也可起促进作用。室温搅拌下,在尿素-氯化胆碱体系的低共熔溶剂中,通过芳香醛和巴比妥酸反应合成5-亚苄基巴比妥酸,实验结果表明,在室温无催化剂条件下,尿素-氯化胆碱低共熔溶剂用量为1.5mL,芳香醛与巴比妥酸的物质的量比为1∶1.1,反应时间2h,5-亚苄基巴比妥酸衍生物3c产率可达92.6%。得到的产物用熔点、红外和核磁进行了表征。     

氯化胆碱/草酸低共熔溶剂高效脱除模拟油中硫

在100℃下,将草酸与氯化胆碱按照等物质的量混合搅拌制备氯化胆碱/草酸低共熔溶剂(Ch Cl/H_2C_2O_4)。采用红外光谱(IR),热重(TGA)和氢谱(1HNMR)对其结构分别进行了相关表征分析。以Ch Cl/H_2C_2O_4低共熔溶剂作为萃取剂和催化剂,过氧化氢为氧化剂氧化脱除模拟油中的二苯并噻吩。分别考察了反应温度、过氧化氢用量以及不同含硫化合物对脱硫率的影响。实验表明最优反应条件为5 m L模拟油,1 m L的Ch Cl/H_2C_2O_4低共熔溶剂,0.3 m L的过氧化氢,反应温度为40℃,在160 min的最佳反应条件下DBT的脱除率高达93.4%。结果表明其表观活化能较低。在5次循环反应以后,其脱硫效果略有降低,表明该低共熔溶剂的催化脱硫活性和稳定性较高。     

乙苯,苯乙烯的生产及合成乙苯,苯乙烯催化剂的研究进展

苯乙烯是重要的石油化工原料。本文介绍了国内外苯乙烯生产的发展概况，合成乙苯，苯乙烯所用的催化剂种类，并就苯乙烯生产及催化剂的发展趋势提出了自己的观点。     

Synthesis and characterization of homopolymers and copolymers of various acrylates and acrylonitrile

Various homopolymers and copolymers of methyl acrylate, ethyl acrylate, butyl acrylate, and acrylonitrile in different feed ratios were synthesized. These were characterized by IR, ¹³C-NMR, DSC, DTA, and TGA. Spectroscopic characterization helped in differentiating copolymers of different mol ratios. Thermal analysis revealed different degradation patterns for homopolymers and copolymers. The temperature and energy changes associated with various phase transitions were dependent on the chemical composition of homo- and copolymers, as expected. © 1993 John Wiley & Sons, Inc.     

生物质气化及生物质与煤共气化技术的研发与应用

总结了生物质原料的特点及生物质单独气化的缺点;介绍了国内外生物质气化技术及生物质与煤共气化技术的研发与应用现状;分析了在此领域国内外的发展趋势与前景;概括了开展生物质与煤共气化技术研发的意义。     

Electronic structures and reactivities of monometallic and bimetallic clusters of Au and Cu

The variation of the Au 4f binding energy of Au clusters with the cluster size has been established by measuring the binding energies of clusters whose size distributions were independently determined by HREM and STM. The binding energy increases significantly when the cluster size is less than 2 nm. Au-Cu bimetallic clusters of the composition Cu₃Au have been deposited for the first time on carbon substrates. The shifts in the core level binding energies of the bimetallic clusters show the effect of alloying in the case of large clusters, but show effects of both alloying and cluster size in the case of the small clusters. The interaction of CO with Cu₃Au clusters is stronger than with a bulk Cu metal. The interaction of CO with small Cu clusters also seems to be stronger than with bulk Cu or with large Cu clusters.     

钾盐资源及钾肥供需情况分析及预测

阐述了国内外钾盐资源及钾肥生产现状,对国内外钾盐的供需形势进行了分析及预测,从资源、原材料、国际市场三方面提出了解决我国钾盐短缺的措施。     

Kinetics and Mechanism of Oxidation of Mono- and Polyacetals

Abstract

Kinetics and mechanisms of oxidation of 6 acetals by molecular oxygen and ozone in liquid phase have been studied. Reaction with molecular oxygen (70°C, 15–16 hr) leads to the formation monoethers of the corresponding glycols with 68–90% selectivity. Salts of metals and complexes with crown-ethers have increased the reaction rate significally. Ozone have reacted with acetals with formation similar products. The mechanisms of intermediate stages have been proposed.     

Comparison of the Adhesion and Cohesion of Triblock and Random Copolymers of Styrene and Butadiene

A substantially greater detachment energy is required to strip a polyethylene tereph-thalate (Mylar) film from a styrene-butadiene-styrene (SBS) triblock copolymer compared to that for peeling from a random styrene-butadiene (SBR) copolymer. This is true even though the intrinsic interaction between the Mylar and each elastomer is expected to be similar because of their virtually identical chemical composition. It is proposed that this difference in peel strength (between the SBS and SBR) is a consequence of the much higher dissipative capacity of the former elastomer. Another manifestation of this is the higher cohesive tear strength of the SBS compared to the SBR. Extents of energy dissipation within each elastomer during detachment of the Mylar adherend are consistent with the hypothesis that the average maximum stress experience before detachment is some similar fraction of each elastomer's tensile strength.     

Wetting properties of homopolymers and copolymers of pentafluorostyrene and methylacrylate and homopolymer blends

Polypentafluorostyrene (PPFS), polymethylacrylate (PMA), and poly(pentafluorostyrene-co-methylacrylate), poly(PFS-co-MA) were prepared and the wetting characteristics of polymer blends of PPFS and PMA were compared with that of poly(PFS-co-MA) via contact angle measurements. The critical surface tension of polypentafluorostyrene was found to be 22.6 dyne/cm, which is comparable to the value reported for polytrifluoroethylene (22 dyne/cm). The critical surface tension of poly(PFS-co-MA) is not linearly related to its composition. The polymer blends of PPFS and PMA exhibit significant surface enrichment of the fluoropolymer. The harmonic-mean method¹ was employed to determine surface tensions of these polymers and many known polymers. It is found that the method produces useful surface tension data provided the contact angle values are derived from testing liquids of dissimilar polarity.     

实施水泵节能技改 实现节能降耗

介绍了内蒙古亿利化学工业有限公司在满足生产的前提下,对现有的循环水泵实施的节能技改及效果。     

泡沫起泡性、稳定性及评价方法

本文论述了泡沫的两个基本性质:起泡性和稳定性。对起泡性和提高泡沫稳定性的方法作了评价。