煤化程度对煤基固体酸结构及其水解纤维素性能的影响

利用煤具有缩合芳环、脂肪侧链及含氧官能团的结构特点，采用不同煤化程度的煤为碳源，在不同炭化温度下制备了煤基固体酸催化剂（CSA）。通过XRD、FT-IR、¹³C NMR对催化剂结构进行了表征。以还原糖和葡萄糖的产率为考察指标，探讨了煤化程度和炭化温度对煤基固体酸非均相催化水解纤维素的影响。结果表明，煤作为碳源具有传统碳源所不具备的结构优势，煤基固体酸碳层片上除含有磺酸基、酚羟基和羧基外，还含有传统碳基固体酸不具备的桥键（-O-、-CH₂-）和侧链（-CH₃、-OCH₃、-CH₂CH₃）。除磺酸基外，其余均由煤的结构演化而来。随着炭化温度的升高，催化剂的芳香度增大、活性基团的种类和数量减少、磺酸基密度逐渐下降，且随着煤化程度增加，煤基固体酸结构可调性降低，所需要的最佳炭化温度也逐渐降低。不同种类的煤基固体酸在水解纤维素过程中表现出了较高的活性，其中，霍林河煤基固体酸的活性最高。水解活性受催化剂芳香片层大小及堆叠高度、片层之间桥键和磺酸基密度等因素的影响，是众多活性基团协同作用的结果。     

低阶煤两段化学降解产物的组成性质

用硝酸对低阶煤在常压、加压条件下进行处理 ,可获取高收率的煤基水溶酸 (40～ 50 % ) ;氧化残渣中加入助剂在中性条件下进行二次降解 ,进一步提高水溶酸的收率。考察了对水溶酸在组成、性质、结构方面的特性并与晋城煤的黄腐酸 (FA)作比较 ,可知水溶酸在性能方面优于FA。实验发现 ,煤氧化降解过程中其结构变化主要发生在氧化阶段 ,降解过程对水溶酸中活性基团的增加贡献不大 ;一次氧解产物中含有大量的脂肪结构 ,而风化煤二次降解产物中稠环化程度高 ,与FA相似。     

先锋褐煤及其热溶残煤的过氧化氢氧解

利用1-甲基萘（1-MN）对先锋褐煤进行热溶,并在温和条件下分别对原煤及其热溶残煤进行过氧化氢氧化。结合元素分析和FT-IR对各级产物进行结构表征,用GC/MS对氧化反应水溶性产物的甲酯化衍生物进行分析。结果表明,先锋褐煤在1-MN中的热溶率较低,320 ℃下热溶残煤（TR）的收率为81.01%,该煤主要以共价键交联的大分子结构为主,非共价键缔合的小分子含量较低,并以脂肪结构为主,含一定量的羰基以及少量的羟基和芳香结构。原煤和热溶残煤氧化水溶性产物中α,ω-二羧基烷酸含量较高,同时还发现,相当含量的芳香酸及三元羧酸存在,其中,α,ω-二羧基烷酸主要以丙二酸和丁二酸为主;原煤中可溶小分子易被氧化并生成较复杂的产物。与原煤相比,热溶残煤结构更为规整,氧化主要以共价键交联的大分子结构的氧化解聚为主,氧解率较低,水溶性氧解产物也较简单,种类较少,据此推测先锋褐煤的桥键主要以为-CH₂-和-CH₂-CH₂-为主。     

PbO2将Mn2＋氧化成几价

研究了在酸性介质中，Ｍｎ~（２＋）被ＰｂＯ_２氧化的产物，氧化产物的物种与反应条件──酸浓度、温度、ＰｂＯ_２用量的关系。实验结果表明：酸浓度较高时（ＣＨ_２ＳＯ_４≥６ｍｏｌ·Ｌ（－１）），有利于Ｍｎ~（３＋）的生成与稳定；酸浓度较低时，有利于ＭｎＯ_４~－的生成；在酸浓度居中时，也有可能得到Ｍｎ（Ⅳ）。氧化剂用量的增加，温度的提高有利于ＭｎＯ_４~－的生成。     

O－烷基化对煤中氢键的调控及对热解特性的影响

采用O－烷基化的方法对霍林河褐煤进行预处理，用原位漫反射红外光谱结合热重研究了处理前后煤中氢键的变化规律及热解特性。提出采用煤中高岭土、伊利石等在3690cm－1附近的红外吸收峰作为标准，校正煤的漫反射红外谱图的方法。结果表明，采用O-烷基化方法处理霍林河原煤后，其中的氢键数量有明显的减少，但均不能完全消除煤中的氢键；对于各种氢键调控幅度的大小随氢键强度的增大而逐渐减少；调控后煤中的氢键在高温区的热解稳定性增加；经O-烷基化后，煤的热解转化率增加，初始温度降低，热解温区加宽，失重速率加快。     

煤基富勒烯烟灰萃取产物的质谱分析

用甲苯等有机溶剂对由煤制得烟灰(soot)进行索氏萃取，用时间飞行质谱及气相色谱-质谱联用（GCMS）技术对所得的萃取产物进行了分析，结果发现，煤基粗富勒烯中除含有大量的C60和C70外，高碳富勒烯（如C74、C78，C82、C84、C100及C106等）的丰度也较高。在煤基粗富勒烯的伴生副产物中存在一些含有苯环结构的芳香性碳氢化合物和少量的长烷烃化合物，由此推测煤基富勒烯的形成过程可能遵循着一条与以石墨为原料时的机制完全不同的途径。     

山豆根中苦参碱和氧化苦参碱的胶束毛细管电泳法测定

用胶束毛细管电泳法（MECC）测定山豆根中的苦参碱及氧化苦参碱的含量，以盐酸麻黄碱作内标物，20mmol/L硼砂缓冲溶液（含30mmol/L十二烷基硫酸纳，体积分数40％甲醇）作电解质（pH=9.35），于208nm紫外检测，山豆根提取液中有效成分都获得基线分离；定量分析表明，苦参碱的质量浓度在0．08－0．52g/L、氧化苦参碱质量浓度在0．03－0．44g/L其峰面积与质量浓度呈线性关系（r分别为0．9987和0．9976）；此外，还讨论了不同缓冲液浓度、十二烷基硫酸钠（SDS）浓度及甲醇含量对2种有效成分迁移行为的影响。     

高碱煤钠赋存形态及其燃烧过程中迁移转化的研究进展

随着新疆超大煤田的相继发现，新疆煤凭借储量大、碱金属含量高、在热利用过程中易造成锅炉沾污、结垢等问题而得到普遍关注。对高碱煤在燃烧过程中钠挥发特性及其影响因素进行更全面的探究，可为高碱煤的高效清洁利用提供重要参考。本文统计、分析了已发表论文中高碱煤燃烧钠挥发特性的相关数据，研究得到，绝大多数高碱煤中的钠以水溶性钠为主，部分煤（神华宽沟煤和后峡煤）则以不溶性钠为主；不溶性钠含量较高的煤，盐酸可溶性钠和醋酸可溶性钠含量也较高。本文对比研究了四个主要影响钠迁移转化的因素（钠形态和含量、Cl的含量、灰组分和燃烧温度）得出，温度对钠挥发量的影响最大，温度的升高可显著增加钠挥发量，900℃后又可加快挥发速率；当钠含量分布在2000-4000 μg/g时，挥发量与总量之间具有良好的正相关，与可溶性钠含量无关；当燃料中Na和Cl物质的量比低于3.5时，Cl对钠的挥发有明显的促进作用，大于10以后，钠的挥发量较低；钠挥发量与Na和[（Si+Al）-（Ca+Mg）]物质的量比有明显的负相关。本文根据现有的研究成果，考虑钠的赋存形态及影响挥发的因素后，将钠在燃煤过程中的迁移转化行为归纳为三个阶段（内部转化、外部挥发和转化、凝结）和四条路径。     

温度与碱浓度对FeO4^2-/FeO2^-体系电化学行为的影响

研究了影响Fe（OH）3进行酸式电离反应的因素，在多种浓度和温度条件下的NaOH浓溶液中采用SnO2-Sb2O3／Ti电极，研究FeO4^2-/FeO2^-体系的电化学氧化还原反应参数及其变化趋势，结果证实该体系发生电化学氧化还原反应的最佳碱溶液浓度范围为12—14mol／L，最佳温度范围为295～315K．阐明了在实验条件下FeO4^2-/FeO2^-氧化还原体系中存在由FeO4^2-/FeO2^-构成的氧化还原电对，而FeO2不直接与FeO2构成氧化还原电对；并给出了FeO4^2-/FeO2^-氧化还原体系的Latimer图．     

煤及其干馏物氧化产品中苯羧酸的GC分析

煤及其干馏物氧化产品中苯羧酸的ＧＣ分析李福祥吕志平薛建伟秦梦庚（太原理工大学精细化工研究所太原０３００２４）关键词煤氧化，苯羧酸，重氮甲烷，酯化煤及其衍生物经碱氧气或高锰酸钾等氧化后的主要产品是水溶性的羧酸混合物，它是一种吸湿性的固体，具有黄色到近...     

Evaluation of the cytotoxicity on breast cancer cell of extracts and compounds isolated from Hyptis pectinata (L.) poit

Abstract

Hyptis pectinata is a herb popularly used in Brazil for the treatment of inflammations, pain, bacterial infections and cancer. In the present study, inflorescences (MPIn), leaves (MPL), branches (MPB), root (MPR) extracts and three compounds isolated from MPIn were assayed against breast tumor cell lines. The structures of the three compounds (pectinolide J, hyptolide and pectinolide E) were determined by means of spectroscopic analysis. Pectinolide J was isolated for the first time. The MPIn, MPL and MPR exhibited specific antiproliferative activity on tumor cell lines when compared to normal cell lines with IC₅₀ of 52.01?±?0.64, 45.91?±?0.02?μg/mL and 82.84?±?0.03?μg/mL, respectively. Although the isolated substances did not present good antiproliferative activity, when the three were associated, a greater biological effect was observed, suggesting a synergistic effect. Hyptolide (5.6?±?0.4?μg/mL) showed IC₅₀ sufficiently low to be considered as a drug prototype.     

Thin-layer chromatographic detection of monocrotophos in biological materials

An organophosphorus insecticide monocrotophos is increasingly being used in agriculture to control insects on a wide range of crops. Its ready access has resulted in misuse in many instances of homicidal and suicidal poisoning cases. This paper describes a chromogenic spray reagent for the detection of monocrotophos in biological materials by thin-layer chromatography. Monocrotophos on alkaline hydrolysis yields N-methylacetoacetamide which in turn reacts with diazotized sulphanilamide or sulphanilic acid to give a red colour. Other organophosphorus insecticides do not give a coloured spot. Moreover, organochlorine and synthetic pyrethroid insecticides and constituents of viscera (amino acids, peptides, proteins etc.) which are generally co-extracted with the insecticides, do not interfere. However, phenolic compounds and hydrolysed product of carbamate insecticides, may interfere and are differentiated from monocrotophos by R_F values. The limit of detection is ca 1 μg.     

光催化降解磷酸酯类农药的研究

以TiO₂/beads作为光催化剂,研究了磷酸酯类农药光催化降解的规律.结果表明,低浓度的磷酸酯类农药光催化降解符合一级动力学方程;4.0×10^-4mol/L的敌敌畏和久效磷农药,375W中压汞灯照射1.5h,其残留量小于10%,光照3.5h,有机磷被完全光催化降解至PO₄^3-.     

Poly(allylamine hydrochloride) Functionalized Multiwalled Carbon Nanotube Modified Carbon Paste Electrode as Acetylcholinesterase Biosensor Transducer

In this work, a sensitive, practical and reliable acetylthiocholine (ATCh) biosensor based on poly(allylamine hydrochloride) functionalized multiwalled carbon nanotube (PAH/MWCNT) was fabricated and used for pesticide detection. As far as we know, this is the first work that constitutes the usage of PAH and MWCNT for ATCh biosensor. The developed system was characterized by using scanning electron microscopy, electrochemical impedance spectroscopy and cyclic voltammetry. The influence of parameters such as enzyme amount and pH were examined and a linearity between 5×10^?5 M?2.0×10^?3 M for ATCh was obtained. The proposed biosensor was applied for a model pesticide, monocrotophos, detection. The analytical curve showed an excellent linearity in the monocrotophos concentration range of 1–25 pg/mL with an incubation time of 5 min. Limit of detection and limit of quantification values were calculated as 0.88 and 2.9 pg/mL, respectively. The system was also applied for detection of monocrotophos in grape, tomatoe, tap and mineralized water samples and promising recovery values were obtained.     

煤炭腐植酸的硅烷化

研究了风化煤、褐煤腐植酸（ＨＡ）及其氧解产物（ＮＨＡ）与卤硅烷的缩合反应。产物的组成分析、红外、ＤＴＡ、吸附性能和表面张力等测定结果表明，ＨＡ及ＮＨＡ同卤硅烷的反应活性与其羧基含量有较好的相关性，卤硅烷的反应活性ＲｎＳｉＣｌ４－ｎ〉ＰｈｎＳｉＣｌ４－ｎ（苯基氯代硅烷）。硅烷化产物具有较好的热稳定性与表面活性。     

ADSORPTION OF NONIONIC SURFACTANTS ON LATEXES

Adsorption isotherms of ethoxylated nonylphenols on poly(styrene) and poly(vinyl chloride) latexes have been measured. The isotherms all reach a limiting adsorption at concentrations somewhat higher than the critical micellar concentrations of the surfactants. The relative affinity of the surfactants to the latex surfaces was found to decrease with increased ethylene oxide chain length. Analysis of the isotherms indicates some affinity of the ethylene oxide chain to the latex surface. This affinity may possibly be attributed to the presence of surface carboxylic groups

Some of the isotherms were obtained using the serum replacement technique developed by S.M. Ahmed et. al. (S.M. Ahmed, M.S. El-Aasser, G.H. Pauli, G.W. Poehlein and J.W. Vanderhoff, J. Coll. Interface Sci., 73 388 (1980). In the application of this technique to the adsorption of nonionic surfactants it was found that polydispersity of the surfactant plays an important role since surfactant species with high affinity to the latex surface will continuously replace other species with lower affinity.     

2, 4-二羟基苯甲醛缩硫脲及其配合物构象及生理活性的理论研究

缩氨基硫脲类衍生物及其金属配合物是20世纪70年代初期人们认为具有潜在生物活性的化合物,具有抗菌、抗病毒及抗癌等生物活性犤1～4犦。我们曾对2,4-二羟基苯甲醛缩硫脲及其与Cu?、Zn?、Ni?的配合物的合成和生物活性进行过研究犤5犦。但由合成方法和物理表征仅能知道其一维连接顺序,而它们的构象及生理活性的理论研究尚未见报道。现代药物分子设计理论认为,药物分子(底物)的活性取决于与生物大分子(受体)活性中心作用时相匹配的活性构象。因此,探讨药物分子的构效关系(QSAR)对药物分子的生理活性研究至关重要。本文利用Gaussian98W在HF…     

INVESTIGATIONS ON THE MECHANISM OF CHLORPROMAZINE PHOTOTOXICITY: EFFECTS ON LYSOSOMES OF CULTURED HUMAN FIBROBLASTS

Abstract The effect of chlorpromazine (CPZ) and UVA on lysosomes of cultured normal human fibroblasts has been investigated. Acid phosphatase (ACPase) activity in 12 000 g pellet of cells treated with CPZ (10 μg/m l ) and UVA (6 × 10⁴ J/m²) was found to be decreased as compared with non-treated, CPZ or UVA treated control cells. This decrease, however, was not accompanied by a concomitant increase in ACPase activity in the 12 000 g supernatant. The addition of Triton X-100 to cells pretreated with CPZ + UVA resulted in only a moderate increase in ACPase activity of the 12 000 g supernatant. ACPase activity of the cells incubated in media containing preirradiated CPZ was also found to he decreased. These results indicate that CPZ + UVA directly inactivate lysosomal enzymes, possibly without affecting the membrane.     

风化煤的化学降解

在Ｍｎ－Ｍｏ催化剂存在下用ＨＮＯ３氧化对风化煤进行了化学降解研究。考察一降解条件，氧化产物收率及组成性质，结果表明，与原煤相比，氧解产物中极性功能团大量增加，极性溶剂中抽提率显著提高。