生活污泥焚烧灰的重金属含量及其浸出特征

为了探讨生活污泥焚烧灰中重金属的含量及其浸出特征,收集了广州沥窖污水处理厂的剩余污泥,采用火焰原子吸收光谱法测量重金属含量;应用固体废物浸出毒性的浸出方法(GB5086.2-1997),以不同p H的浸提剂,对污泥中重金属的浸出特性进行了实验研究。结果表明:污泥中Fe的含量最高,达到27378 mg/kg,其次是Mn和Cu,分别为436.5 mg/kg和315.2 mg/kg,Zn、Cr、Pb和Ni的含量较高,依次是721.5、199.2、122.2和110.8 mg/kg,Cd的含量极少,仅有0.33 mg/kg。Cr和Cd金属元素的8小时浸出量分别为62.9 mg/kg、0.96 mg/kg,其余被测的金属元素:Fe、Pb、Cu、Ni、Zn以及Mn,在任何浸提时间下,其浸出量均为0 mg/kg。本实验中重金属在酸性条件下的浸出率明显高于碱性条件下,Cr、Ni和Cd的最佳浸提剂p H值均为2。其中Cu和Zn随浸提剂p H变化的浸出特征不明显。。     

甜藤蛋糕中微量元素含量的测定

采用火焰原子吸收光谱法和石墨炉原子吸收光谱法,对甜藤蛋糕中微量元素Fe、Zn、Cu和Mn的含量进行测定,得出Fe、Zn、Cu和Mn的高含量分别为:Fe:30. 710 mg/kg,Zn:7. 016 mg/kg,Cu:0. 499 mg/kg,Mn:8. 86 mg/kg。各微量元素含量测定结果的相对标准偏差RSD值在1%至2%之间,测定结果准确可靠。结果表明甜藤蛋糕中微量元素的含量会随着甜藤汁增加而增加。     

叶面喷施有机硒对大豆不同器官吸收Cd、Pb的影响

通过对大豆进行叶面喷施硒蛋氨酸的盆栽试验,发现能明显提高大豆籽粒硒水平,籽粒富集Se的能力约是对照的6倍,不同器官富集Se的规律为:叶粒茎壳,而其产量没有发生明显变化。大豆叶片吸收Cd,Pb的能力最强,其中叶片Cd含量为0.30~0.90 mg/kg,Pb含量为1.0~1.9 mg/kg,叶片Pb含量是籽粒的42~98倍。大豆植株里的Se对籽粒、壳、叶、茎等各器官吸收Cd、Pb均表现出拮抗作用,对Cd的拮抗作用较强,对Pb的拮抗作用较弱。     

盐地碱蓬中矿物质元素的分析研究

采用电感耦合等离子体质谱仪测定了盐地碱蓬根、茎、叶、种子中的矿物质元素含量,并进行了比较分析。结果表明:盐地碱蓬中含有丰富的矿物质元素,其中含量较高的有Na(10200～49290 mg/kg)、Mg(4038～17816 mg/kg)、Ca(629～6078 mg/kg)、K(1877～6137mg/kg)、Fe(159～979 mg/kg)。矿物质元素Fe、Cu、K含量在根中最高,Na含量在茎中最高,Zn、Mg、Ca含量在叶中最高,Mn、Se含量在种子中最高。为进一步探讨盐地碱蓬不同部位的药理作用和合理开发利用该植物资源提供一定的科学依据。     

生物质固定化硫酸盐还原菌处理废水中重金属离子

采用海藻酸钠和3种生物质载体(稻壳、玉米芯、秸秆)固定化的硫酸盐还原菌(SRB)处理单一重金属(700 mg/L Fe2+, 75 mg/L Cu2+, 120 mg/L Pb2+, 80 mg/L Cd2+)废水,筛选出稻壳为效果较优的固定化载体,并对合成重金属废水(含400 mg/L Fe2+, 30 mg/L Cu2+, 50 mg/L Pb2+, 40 mg/L Cd2+)的处理效果作了进一步研究. 结果表明,稻壳固定化SRB去除单一重金属时,Fe2+, Cu2+, Pb2+, Cd2+去除率分别为99%, 100%, 100%, 100%;处理合成重金属废水时,4种重金属去除率分别为98.06%, 100%, 99.35%, 100%.     

火焰原子吸收法测定不同产地香菇中4种微量元素

比较不同产地香菇中Fe、Mn、Zn、Cu 4种微量元素的含量。采用火焰原子吸收法测定不同产地香菇中Fe、Mn、Zn、Cu的含量。结果表明:产地不同的香菇中四种微量元素的含量各不相同,其中Fe和Zn的含量相对较高,Fe最高可达293.47 mg/kg,Zn最高可达69.691 mg/kg;而Cu和Mn的含量相对较低,Cu最高可达35.401 mg/kg,Mn最高可达16.507 mg/kg。不同香菇中对相同元素的富集能力差别较大,福建龙岩(武夷山野生红菇)中各种微量元素均为最高。     

石灰调质污泥重金属形态分布及资源化分析

针对南方某生物滤池(BAF)工艺污水处理厂,分析了初沉污泥、生物污泥、石灰调质污泥中Pb、Zn、Cu、Cd、Ni、Cr六种重金属含量及形态分布。结果表明:三种污泥中生物污泥的重金属含量较低,可作为污泥农用和污泥制砖资源化;石灰调质过程使污泥中Zn、Cu、Pb的总量升高,Cr总量降低,Cd和Ni的总量变化不大;石灰调质过程有利于污泥中的Zn、Cu和Cr从不稳定态向稳定态转化。     

铁氧体与镉共沉淀的试验研究

对铁氧体与镉共沉淀进行了试验研究,并探讨了主要技术参数。结果表明,模拟废水中Cd2 含量在50～200mg·L-1时,在常温、Fe3 /Fe2 (质量比)=2、投料比Fe2 /Cd2 (质量比)=4、pH=10的条件下,Cd2 的去除率可达99%以上,出水镉含量小于0 1mg·L-1,达到排放标准。     

杂质Zn,Fe和Cu对BMIC-AlCl3离子液体电解精炼铝的影响

研究了摩尔比为1:2的BMIC-AlCl3离子液体中杂质元素Zn, Fe和Cu对电解精炼铝的影响. 结果表明,离子液体中Zn(II)/Zn, Fe(II)/Fe和Cu(I)/Cu相对于Al(III)/Al的平衡电极电势分别为0.21, 0.63和0.64 V,比其标准电极电势相对值小得多;在温度80℃和电流密度100 A/m2条件下进行电解精炼,铝合金阳极中的绝大部分Zn, Fe和Cu杂质被去除,阴极铝沉积层中杂质含量随阳极杂质含量增加而升高,但杂质的贫化率降低,电流效率均超过94%,能耗为1.59~1.74 kW×h/kg;电解精炼铝含量为75.3%(w)工业铝合金得到了纯度超过99.8%的金属铝,且沉积层致密平整.     

用于低碳混合醇合成的Fe/CuZnSi催化剂研究

采用沉淀-浸渍方法制备了Fe/CuZnSi催化剂,发现在浸渍Fe过程中生成FeZn2 Cu3 O6.5晶体,它在焙烧过程中分解形成CuO晶体,有利于Cu和Fe相互均匀分布,提高催化剂的CO加氢反应活性,CO转化率主要决定于催化剂中的Fe含量,催化剂中的Cu与Zn质量相等时,液态产物中的醇含量明显增加,C2+醇约占总醇质量的50％.     

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.     

责任和责任心的涵义与结构

责任是人应主动承担的角色义务和对其因过失所造成后果应承担的责罚.有两层涵义:一是义务;二是后果.责任心是个体自觉做好分内事务和履行道德义务的心理倾向,是个性心理品质成分中自我特征维度上的重要内容.责任心具有两个方面的涵义:一是角色分内职责;二是角色道德义务.责任心是一种通过责任认知、责任个性和责任适应的动态形式表现出来的静态品质,责任心是责任心过程结构与责任心关系结构相互制约、相互影响的统一体.     

二甲基二烯丙基氯化铵和丙烯酰胺的合成及应用

用复合引发体系(过硫酸盐-偶氮类引发剂)和脂肪胺类氧化还原体系引发,在实验室获得了单体转化率≥98%,特性粘数高于13.6 dL/g的阳离子共聚物PDA,探讨了控制聚合物分子量的影响因素.     

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.