136 resultados para COD


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The reactions of half-sandwich diselenolate Mo and W complexes (CpM)-M-#(NO)(SePh)(2) (M = Mo; Cp-# = Cp' (1a), MeCp (1b); M = W; Cp-# = Cp' (1c)) with (Norb)Mo(CO)(4), Ni(COD)(2) and Fe(CO)(5) have been investigated. Treatment of (1a), (1b) and (1c) with (Norb)Mo(CO)(4) in PhMe gave the bimetallic complexes: Cp'Mo(NO)(mu -SePh)(2)Mo(CO)(4) (2a), MeCpMo(NO)(mu -SePh)(2)Mo(CO)(4) (2b) and Cp'W(NO)(mu -SePh)(2)Mo(CO)(4) (2c) in moderate yields. Irradiation of (1a) and (1c) in the presence of Fe(CO)(5) gave heterobimetallic complexes Cp'Mo(CO)(mu -SePh)(2)Fe(CO)(3) (3a) and Cp'W(NO)(mu -SePh)(2)Fe(CO)(3) (3c). Ni(COD)(2) reacts with two equivalents of (1a), (1b) and (1c) to give [Cp'Mo(NO)(mu -SePh)(2)](2)Ni (4a), [MeCpMo(NO)(mu -SePh)(2)](2)Ni (4b) and [Cp'W(NO)(mu -SePh)(2)](2)Ni (4c) in good yields. The new heterobimetallic complexes were characterized by i.r., H-1-n.m.r., C-13-n.m.r. and EI-MS spectroscopy.

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Growth hormone (GH), prolactin (PRL) and somatolactin (SL) were purified simultaneously under alkaline condition (pH 9.0) from pituitary glands of sea perch (Lateolabrax japonicas) by a two-step procedure involving gel filtration on Sephadex G-100 and reverse-phase high-performance liquid chromatography (rpHPLC). At each step of purification, fractions were monitored by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) and by immunoblotting with chum salmon GH. PRL and SL antisera. The yields of sea perch GH, PRL and SL were 4.2, 1.0 and 0.28 mg/g wet tissue, respectively. The molecular weights of 19,200 and 20,370 Da were estimated by SDS-PAGE for sea perch GH and PRL, respectively. Two forms of sea perch SL were found: one (28,400 Da) is probably glycosylated, while the other one (23,200 Da) is believed to be deglycosylated. GH bioactivity was examined by an in vivo assay. Intraperitoneal injection of sea perch GH at a dose of 0.01 and 0.1 mug/g body weight at 7-day intervals resulted in a significant increase in body weight and length of juvenile rainbow trout. The complete sea-perch GH amino acid sequence of 187 residues was determined by sequencing fragments cleaved by chemicals and enzymes. Alignment of sea-perch GH with those of other fish GHs revealed that sea-perch GH is most similar to advanced marine fish, such as tuna, gilthead sea bream, yellowfin porgy, red sea bream, bonito and yellow tail with 98.4, 96.2%, 95.7%, 95.2%, 94.1% and 91% sequence identity, respectively. Sea-perch GH has low identity to Atlantic cod (76.5%), hardtail (73.3%), flounder (68.4%), chum salmon (66.3%), carp (54%) and blue shark (38%). Partial amino-acid sequences of 127 of sea-perch PRL and the N-terminal of 16 amino-acid sequence of sea-perch SL have been determined. The data show that sea-perch PRL has a slightly higher sequence identity with tilapia PRL( 73.2%) than with chum salmon PRL(70%) in this 127 amino-acid sequence. (C) 2001 Elsevier Science B.V. All rights reserved.

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利用“铁肥”方法增加海洋初级生产力、吸收大气中的CO2、降低温室效应是目前国际上的一个研究热点。为此,本文利用炼钢企业产生的废料转炉钢渣,系统研究了其对海洋微藻生长的影响, 同时研究了转炉钢渣对海水水质及海洋生物的影响,探讨了其作为“铁肥”材料的可行性。 本文首先研究了转炉钢渣对海水水质的影响,包括金属、营养盐、pH、COD及浊度等理化参数。研究发现,在天然海水中加入转炉钢渣后营养盐均有不同程度的溶出;实验条件下,在天然海水和人工海水中加入钢渣,金属大部份被吸附,个别金属溶出,但基本都达到了一、二类海水标准,而pH明显增高,大多超过了海水水质三、四级(6.88.8)的范围,COD低于一类海水水质标准。实验结果显示,钢渣粒度越小、浓度越大,水质浊度越大,但钢渣的比重一般较大,在水体中可以较快的沉降,所以在实际应用过程中不会对水体的透明度造成不良影响。 研究了转炉钢渣对典型海洋底栖生物(紫贻贝)、海洋游泳生物(日本对虾和中国对虾幼虾)的影响。在实验浓度范围内,钢渣对紫贻贝的急性毒性作用基本可以忽略,但紫贻贝的生长率和摄食率随钢渣浓度的增加有所下降,血细胞个数有所下降,但形态没有显著变化,对紫贻贝的免疫功能没有太大影响。钢渣对日本对虾幼虾的半致死浓度为1.62g/L,对中国对虾幼虾的半致死浓度要高于日本对虾,说明在实验条件下中国对虾幼虾的适应能力高于日本对虾幼虾。 另外,重点考察了转炉钢渣对海洋浮游植物-赤潮异弯藻和中肋骨条藻生长的影响,发现加入钢渣以后,相对于对照组微藻生物量显著增加。当钢渣浓度为124248mg/L时赤潮异弯藻的生物量达到最大,当钢渣浓度达到61124mg/L时,中肋骨条藻的生物量最大;钢渣对两种微藻生长的影响规律是相同的,但是影响程度因不同藻种而有所不同,其中对中肋骨条藻的促进作用更加显著,可能与钢渣中能溶出较大量的硅酸盐有关。在室内实验的基础上,初步估算了通过钢渣对微藻生长的促进作用,近海每平方公里海域对二氧化碳吸收的增加量。

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在害赤潮作为一种全球性的海洋灾害,给海洋环境、水产养殖业和人类健康造成巨大危害,研究赤潮的发生规律,探索新的、经济有效的赤潮的防治方法具有重要的科学意义和应用前景。本文针对中国沿海常见赤潮生物种,研究了粘土矿物双赤潮生物基本生理指标的影响,进一步探讨了粘土矿物的控制赤潮机制;并针对粘土矿物去除效率不高的特点,制备出具有较高絮凝胶效率的改性粘土;此外,本文还首次将无机高分子絮凝效率的改性粘土;此外,本文还首次将无机高分子絮凝剂MMH(混合金属氢氧化物正电胶体)和PSMS(聚硅酸金属盐)用于赤潮治理研究中,并探索了上述赤潮防治剂的环境生态效应,主要成果与内容有:1、粘土矿物的筛选 采集国内外近30种粘土矿物,分别考察了它们对中国沿海常见赤潮生物种赤潮异弯藻(Heterosigma akashiwo)和塔玛亚历山大藻(Alexandrium tamarense)的去除效果。结果表明,不同粘土矿物对赤潮生物的絮凝能力有显著差别,实验筛选出去除效果较好的几种粘土,分别为来自美国的Chemically treated kaolin、WHOI土、江苏吴县高岭土及苏州特号土等。通过絮凝实验得到上述几种粘土矿物对两种赤潮生物的絮凝曲线,发现不同粘土矿物对赤潮生物的最大去除率及达到最大去除率所需的粘土浓度有较大差别,同一粘土矿物对不同赤潮生物的去除效果也不相同。塔玛亚历山大藻较赤潮异变藻更易被粘土矿物去除。2、粘土矿物对赤潮生物的生理效应 研究了高岭土对赤潮异弯藻和塔玛来历山大藻生长繁殖、叶绿素a含量、光合作用以及呼吸作用的影响。结果表明,高岭土对赤潮生物生长、叶绿素a含量及光合作用均有抑制作用,表现为随粘土浓度的增加及作用时间的延长,抑制作用增强,并认为这可能与粘土的加入导致光照效应降低及藻类生长的营养环境改变有关。实验同时发现高岭土对不同赤潮生物的抑制程度不同,塔玛亚历山大藻上述各项生理指标比赤潮异弯藻更易受粘土影响。3、无机絮凝剂的制备及絮凝作用研究 主要考察了无机高分子絮凝剂MMH及PSMS(聚硅酸金属盐),包括聚硅酸氯化铝(PSAC)和聚硅酸硫酸铝(PSAS)的合成及对赤潮生物的絮凝作用。在MMH的合成过程中,考察了镁铝摩尔比及制备温度对MMH絮凝赤潮异弯藻的影响,认为镁铝摩尔比为2的条件下制备的MMH具有较好的絮凝和沉降性能,其絮凝赤潮异弯藻的最佳用量为1.5mmolAl/L。在PSAS的合成中采用三因子三水平的正交试验设计,得到PSAS的最佳制备条件为:SiO_2浓度 = 2%, Al~(3+)/SiO_2 = 1, pH = 4。絮凝实验结果表明,PSAS对赤潮生物的絮凝效果优于传统絮凝剂AS(硫酸铝),同时PSAS对不同赤潮生物的絮凝效果也不同,认为这主要与不同赤潮生物的形态结构、运动性及胞外分泌物有关。4、粘土矿物表面改性及机理研究 为提高粘土矿物去除赤潮生物的效率,分别用插入法和表面吸附法制备改性粘土。实验得出插入法的最佳制备条件为:制备温度70 ℃,镁离子浓度2mol/L;表面吸附法中粘土和MMH(混合金属氢氧化物胶体)的适宜配比为:粘土/MMH=10。改性后粘土去除赤潮异弯藻的效率较改性前提高2-3倍。相关分析表明,改性粘土去除赤潮生物的效率与改性后表面电位呈正相关,两种情况下R~2均大于0.8,说明表面电位是影响粘土矿物去除赤潮生物的一个重要因素。5、赤潮治理的现场模拟实验及环境生态效应 在1999年夏季胶州湾中肋骨条藻(Skeletonema costatum)赤潮的发生现场进行了改性粘土及PSAS对藻类去除率、悬浮物、DO、COD、pH等指标的影响研究。结果表明,改性粘土及PSAS对现场中肋骨条藻有较高的去除率,1g/L的改性高岭土和改性蒙脱土对中肋骨条藻的去除率分别可达77%和93%,1ml/L的PSAS去除率达90%以上。DO的含量轻微下降,不致影响其他生物的生长,COD下降幅度较大,达50-80%。6、赤潮防治剂对中国对虾的毒性研究 进行了粘土、次氯酸钙、氯化铝和氯化铁对中国对虾的毒性试验,结果表明,1g/L的高岭土对虾基本无毒性;次氯酸钙在低浓度下对对虾无毒,在高浓度下对对虾有急性毒性效应,安全使用浓度为0.5ml/L游离氯;氯化铝和氯化铁在对虾体内有一定的积累,其长期的毒性效应有待于进一步的分析。上述几种试剂均可用于粘土矿物的改性处理中,是比较安全的赤潮防治剂。

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本文以室内实验为基础,研究了改性粘土治理有害赤潮的方法对生态环境的影响。研究结果表明:有机和无机改性粘土对溶解氧(DO)、化学耗氧量(COD)、pH等主要水质因子均有改善作用;对营养盐,尤其是磷酸盐有一定的吸附作用,在外加磷酸盐为0-0.3μmol/ml范围内,吸附量随水体中磷酸盐浓度的增加而增大,有机改性粘土对海水中磷酸盐的吸附能力为:有机改性粘土Ⅰ>有机改性粘土Ⅱ>有机改性粘土Ⅲ。通过有机改性粘土对磷酸盐的吸附-再释放情况,进一步探讨了其磷酸盐的释放对赤潮异弯藻(Heterosigma akashiwo)、东海原甲藻(Prorocentrum donghaiense)等赤潮生物生长的影响。实验结果显示,经过有机改性的粘土有利于提高其对磷酸盐的吸附能力,降低对磷酸盐的解吸率,利用有机改性粘土治理赤潮可以缓解海水富营养化程度,即使被吸附的部分磷酸盐能缓慢释放,但仍不足以维持赤潮生物的正常生长。无机改性粘土对磷酸盐和硝酸盐与有机改性粘土有相似的吸附性能。其添加剂PAC的重金属含量符合沉积物排放要求,不会对环境造成压力。 其次,以太平洋牡蛎(Crassostrea gigas)幼贝为对象,研究了有机改性粘土Ⅱ和无机改性粘土在对海洋底栖生物的影响。急性毒性试验中二者对牡蛎幼贝的半致死浓度(LC50)分别为4.62 g/L和2.67 g/L,均远远大于改性粘土去除赤潮藻的浓度。在能够有效去除赤潮微藻的粘土浓度条件下,经慢性毒性试验发现改性粘土对牡蛎幼贝成活率、生长和摄食略有降低,但无明显影响,在牡蛎幼贝鳃组织和消化道组织的超微结构中未发现机械损伤。 最后,研究了改性粘土在对去除有毒赤潮藻过程中对底栖生物的影响。以能产生麻痹性贝毒(PSP)的塔玛亚历山大藻(A. tamarense,ATHK)为例,研究了PSP在水体中和粘土沉积层中的分布,发现改性粘土去除塔玛亚历山大藻能有效降低水体中藻细胞浓度及其所携带的PSP毒素。由于藻细胞破裂, 虽然沉积层中藻细胞体内部分PSP毒素溢出,但通过塔玛亚历山大藻细胞不同组分对牡蛎的影响发现,细胞内容物和细胞碎片对牡蛎没有明显毒副作用,由此推断改性粘土对藻细胞絮凝沉降后,能降低对生物的不良影响。此外,室内实验模拟了去除赤潮生物塔玛亚历山大藻(A. tamarense,ATHK)、东海原甲藻 (P. donghaiense )、赤潮异弯藻 (H. akashiwo)过程中,比较改性粘土和赤潮微藻对生物体的影响发现改性粘土在去除赤潮藻过程中能提高牡蛎的存活率,进一步证明改性粘土在赤潮生物防控中,是一种有效的应急措施。

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在基础饲料中分别添加0.04%低聚木糖、0.13%酵母细胞壁、0.08%胆汁酸和同量组合添加,形成5个处理组。采用随机区组试验设计,将体重151.3±15.2 g 的健康大菱鲆鱼165尾平均分配到5个处理组(A~E)中(每组3重复),经72天试验,进行了生长、水质、消化、免疫等试验和测定,结果如下: 组合组的生长效果和饲料利用率最好,酵母细胞壁或低聚木糖单独添加,表现出优良的促生长和饲料利用率;单独添加胆汁酸也有良好效果。4试验组(组合组、酵母细胞壁组、低聚木糖组、胆汁酸组)与对照组比较,增重率分别提高15.4%、13.9%、12.4%(p<0.05)和7.4%(P>0.05),饲料系数分别降低6.9%、6.2%、5.4%(p<0.05)和3.8%(P>0.05)。 不同添加剂及组合对试验鱼所处水环境因子变化仅有小幅影响,统计差异不显著(p>0.05)。4试验组比对照组的水体氨氮含量分别提高4.0%、3.2%、3.0%和0.8%(P>0.05),COD含量分别提高2.8%、-2.2%、-3.4%和0.8%(P>0.05)。根据试验结果,建议水环境因子(氨氮、磷酸盐、COD等)作为水产动物营养与饲料研究的主要衡量指标之一。 3种添加剂组合后达到提高生长大菱鲆非特异性免疫功能的最优效果,对补体C3和C4、细胞吞噬活力和SOD的提高作用尤为显著;酵母细胞壁单独添加对补体C3和细胞吞噬活力的作用更加显著;低聚木糖单独添加对补体C4和细胞吞噬活力的作用显著;单独添加胆汁酸提高免疫力的作用相对较弱。 4试验组比对照组的蛋白质消化酶活力在胃和前肠,分别提高20%和24%、17%和19%、16%和15%(p<0.05)、11%和3%(P>0.05);脂肪消化酶活力在前肠和中肠,分别提高22%和19%、19%和17%(p<0.05)、7%和12%(p>0.05)、19%和18%(p<0.05)。 4试验组比对照组的蛋白质消化率分别提高了3.6%、2.9%、3.7%(p<0.05)和1.5%(p>0.05);粪蛋白质排出量减少12.7%、7.1%、13.4%和2.4%(p>0.05)。说明,3种添加剂显著提高了生长大菱鲆蛋白质消化率,使粪蛋白质排出量不同程度降低,显示了试验使用添加剂的无公害效应。 权衡不同添加剂及其组合对大菱鲆生长期生长性能、饲料利用率、水生态因子、消化酶活力、非特异性免疫、蛋白质消化与粪蛋白质排出的综合影响,本研究从生态与环保角度得出:3种添加剂组合的效果最好,酵母细胞壁或低聚木糖单独添加表现出优良效果;单独添加胆汁酸也有良好作用。

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本文根据1999年-2007年间7个航次的长江口及其邻近海域的鱼类浮游生物和环境因子的调查资料,探讨了三峡工程蓄水前后长江口鱼类浮游生物群落特征,主要包括长江口鱼类浮游生物的种类组成、数量变动、群落多样性、空间分布格局等,分析了三峡工程蓄水前后长江口鱼类浮游生物群落结构的动态变化,为评价三峡工程对河口生态环境及鱼类补充资源的影响提供科学依据,研究结果如下: 1.三峡工程蓄水前春季(1999年5月和2001年5月)共捕获11540个鱼类浮游生物隶属11目18科32种,其中凤鲚(Coilia mystus)、鳀(Engraulis japonicus)、六丝矛尾鰕虎鱼(Chaeturichthys hexanema)、白氏银汉鱼(Allanetta bleekeri)、松江鲈(Trachidermis fasciatus)为优势种;鱼类浮游生物群落可划分为三个类群:①以凤鲚为优势种的河口群组,②以松江鲈和白氏银汉鱼为优势种的沿岸群组,③以鳀和六丝矛尾鰕虎鱼为优势种的近海群组;盐度、深度、溶解氧和悬浮体是影响这一海域鱼类浮游生物分布的主要环境因子。 2.三峡工程蓄水后春季长江口的环境因子总体分布格局没有改变,部分环境因子表现出数量上的差异:溶解氧含量偏低,COD平均值下降,pH值显著上升,盐度升高,河道水域和口门附近悬浮体下降,长江口鱼类生物群聚栖息环境发生了变化。三峡工程蓄水后春季(2004年5月和2007年5月)共采获的25种鱼类浮游生物,总丰度(1 070个)仅为蓄水前(11 540)的10%,4种优势种白氏银汉鱼、凤鲚、松江鲈和鳀贡献了总丰度的94.57%;蓄水后影响长江口鱼类浮游生物格局的主要环境因子是盐度和悬浮体,蓄水后长江口鱼类浮游生物群聚类型(河口型、沿岸型和近海型)与蓄水前一致,但沿岸型空间分布区域明显减少,近海型分布区域向河口方向扩展。长江口环境因子中,盐度和悬浮体是蓄水前后鱼类浮游生物群聚变异的主要影响因素。 3.三峡工程蓄水前后春季四次调查共记录鱼类浮游生物39种,生态类型包括淡水、半咸水、沿岸和近海。春季长江口鱼类浮游生物优势种包括鯷、凤鲚、白氏银汉鱼、松江鲈和六丝矛尾鰕虎鱼,2004年和2007年鯷、凤鲚优势地位有所下降。长江口鱼类浮游生物群落结构年度间差异显著,以2004年长江口鱼类浮游生物群落结构与1999和2001年相异性最高,鯷和凤鲚种群数量变动对其群落变异的贡献率最大,群落相似性以2004和2007年最高,达71.17%。与蓄水前相比,三峡水库蓄水后的长江口鱼类浮游生物群落多样性显著下降。1999—2007年间,长江口发生了一系列环境环境条件变化,直接或间接的环境干扰带来了长江口鱼类生物群落结构变异。 4.2007年四个航次(春、夏、秋、冬)共捕获鱼类浮游生物6,463个, 隶属12目28科45种, 以鳀科丰度最高, 占总丰度的76.5%。长江口鱼类浮游生物包括4种生态类型: 淡水型(2种), 半咸水型(14种), 沿岸型(10种)和近海型(16种)。其中, 近海型物种个体数量最多, 占2007年长江口鱼类浮游生物总丰度的74.55%。鳀在4个季节均有出现, 对长江口鱼类浮游生物丰度贡献最大。鱼类浮游生物在物种组成上存在明显的季节变化: 白氏银汉鱼在春季占绝对优势, 鳀是夏季优势度最高的种类, 秋季除鳀外, 前颌间银鱼(Hemisalanx prognathus)成为优势种; 鱼类浮游生物丰度高度集中在优势种上, 各季节优势种对总丰度贡献超过89%。群落物种数量、丰度、丰富度指数、均匀度指数和多样性指数, 在夏季最高, 春季和秋季次之, 冬季最低。2007年长江口鱼类浮游生物的群落格局在空间上分为三个不同的群组:河口、沿岸、外海,并且这种分布随长江冲淡水的季节变化而变化。盐度是影响决定长江口鱼类浮游生物群落空间分布的最重要因子,而温度则是影响其季节性结构变化的主要因子。此外,生殖洄游和索饵洄游也是影响鱼类浮游生物群落结构时间变化的重要因子。

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生物滤器是封闭循环水养殖系统的核心单元,而生物填料对生物滤器的功能发挥起着关键的作用。本论文研究了四种不同填料、不同C:N比对生物滤器硝化效能的影响。结果表明:(1)陶粒比表面积最大;竹制空心生化球(竹球)填料的比重和水接近,性能最佳;麦饭石的粒径最小;(2)在较高的C:N下竹球的COD去除速率和氨氮去除速率最高,塑料生物滤球去除速率最低;在较低的C:N下,麦饭石具有最高的COD和氨氮去除速率,竹制空心生化球略低,并高于其他两种填料:COD去除速率随着C源含量的升高而升高,氨氮去除速率随着C源含量的升高而降低;(3)在不同C:N下,不同填料的氨氮去除百分比差异很大。竹制空心生化球、麦饭石以及陶粒等三种填料的氨氮去除百分比随时间的变化呈指数上升趋势;而竹制空心生化球的氨氮去除百分比的变化呈直线上升趋势;(4)填料的种类能够影响生物滤器的运行稳定性。在温度18-22℃,HRT 0.5 h的运行条件下,四种填料生物滤器的硝化细菌成熟挂膜约需40-60天左右;(5)生物滤器的氨氮去除速率随时间而提高,达到最高值并在一段时期保持恒定;(6)生物滤器去除氨氮具有一定周期性,进而导致生物滤器出水的氨氮浓度产生波动。这可能是由于生物膜细菌生长、繁殖、成熟的周期性导致。

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1、在封闭循环水工厂化养殖条件下,进行为期44天的6×2双因素随机设计动物试验,即6个体重阶段(45-550g)和2种养殖密度水平(高密度比正常密度提高20-30%),探寻我国北方工厂化养殖半滑舌鳎生长、摄食和水质的变化特征及规律。结果如下: (1)日增重、日均摄食量、饲料系数等绝对指标与体重阶段呈正相关,对应的增重率、特定生长率和摄食率等相对指标与其呈负相关;氨氮、COD等水生态指标相对浓度与体重阶段呈负相关。(2)新发现半滑舌鳎的日摄食率为0.43-0.92%,对常规鱼类投饲率推荐范围(2-5%)提出了质疑,为现代海水养殖精准饲喂和清洁生产提供了科学依据。 2、在封闭循环水养殖条件下,通过56天的4×2双因素随机设计动物试验,探寻月饱食度和和日粮次喂比例对工厂化养殖半滑舌鳎幼鱼(291.47±4.23g)生长与免疫的影响。结果如下: (1)月饱食度显著影响鱼的生长、摄食和水氨氮相对浓度,对饲料系数、水质其它指标和血液免疫无显著影响。 (2)日次喂比例显著影响鱼生长、饲料系数和水氨氮指标等,对水质其它指标、摄食量及免疫指标无显著影响。等量投喂组的生长和水氨氮指标显著高于差量投喂,饲料系数低于差量投喂。 (3)确定90%月饱食度与差量投喂为兼顾生长和水环境的生态适宜投喂组合模式,100%月饱食度与等量投喂为获得最快生长的投喂组合模式。 3、通过对实验数据进行对数化处理、多 元线性拟合、变量替代等方法,初步建立了封闭循环水养殖半滑舌鳎的投喂模型、总有害氮排泄和日增重预测模型。本模型的建立和完善,可初步实现最佳生长、最 少饲料浪费、并向生物滤器提供稳定代谢物的新型工厂化养殖清洁投喂目的,使封闭循环水养殖半滑舌鳎的饲料投喂和水环境调控步入数字、精准、动态的层次。

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The research on mechanical effects of water-rock and soil interaction on deformation and failure of rocks and soils involves three aspects of mechanics, physics and chemistry. It is the cross between geochemistry and rock mechanics and soil mechanics. To sum up, the mechanical effects of water-rock and soil interaction is related to many complex processes. Research in this respect has been being an important forward field and has broad prospects. In connection with the mechanism of the effects of the chemical action of water-rock on deformation and failure of rocks and soils, the research significance, the present state, the developments in this research domain are summarized. Author prospects the future of this research. The research of the subject should be possessed of important position in studying engineering geology and will lead directly to a new understand on geological hazard and control research. In order to investigation the macroscopic mechanics effects of chemical kinetics of water-rock interaction on the deformation and failure, calcic rock, red sandstone and grey granite reacting chemically with different aqueous solution at atmospheric temperature and atmospheric pressure are uniaxially compressed. The quantitative results concerning the changes of uniaxially compressive strength and elastic modulus under different conditions are obtained. It is found that the mechanical effects of water on rock is closely related to the chemical action of water-rock or the chemical damage in rock, and the intensity of chemical damage is direct ratio to the intensity of chemical action in water-rock system. It is also found that the hydrochemical action on rock is time-dependent through the test. The mechanism of permeation and hydrochemical action resulting in failure of loaded rock mass or propagation of fractures in rocks would be a key question in rock fracture mechanics. In this paper, the fracture mechanical effects of chemical action of water-rock and their time- and chemical environment-dependent behavior in grey granite, green granite, grey sandstone and red sandstone are analyzed by testing K_(IC) and COD of rock under different conditions. It is found that: ①the fracture mechanical effect of chemical action of water-rock is outstanding and time-dependent, and high differences exist in the influence of different aqueous solution, different rocks, different immersion ways and different velocity of cycle flow on the fracture mechanical effects in rock. ②the mechanical effects of water-rock interaction on propagation of fractures is consistent with the mechanical effects on the peak strength of rock. ③the intensity of the mechanical fracture effects increases as the intensity of chemical action of water-rock increases. ④iron and calcium ion bearing mineral or cement in rock are some key ion or chemical composition, and especially iron ion-bearing mineral resulting in chemical action of water-rock to be provided with both positive and negative mechanical effects on rock. Through the above two tests, we suggest that primary factors influencing chemical damage in rock consist of the chemical property of rock and aqueous solution, the structure or homogeneity of rocks, the flow velocity of aqueous solution passing through rock, and cause of formation or evolution of rock. The paper explores the mechanism on the mechanical effects of water-rock interaction on rock by using the theory of chemistry and rock fracture mechanics with chemical damage proposed by author, the modeling method and the energy point of view. In this paper, the concept of absorbed suction between soil grains caused by capillary response is given and expounded, and the relation and basic distinction among this absorbed suction, surface tension and capillary pressure of the soil are analyzed and established. The law of absorbed suction change and the primary factors affecting it are approached. We hold that the structure suction are changeable along with the change of the saturation state in unsaturated soils. In view of this, the concept of intrinsic structure suction and variable structure suction are given and expounded, and this paper points out: What we should study is variable structure suction when studying the effective stress. By IIIy κHH's theory of structure strength of soils, the computer method for variable structure suction is analyzed, the measure method for variable structure suction is discussed, and it reach the conclusions: ①Besides saturation state, variable structure suction is affected by grain composition and packing patter of grains. ②The internal relations are present between structure parameter N in computing structure suction and structure parameter D in computing absorbed suction. We think that some problems exit in available principle of effective stress and shear strength theory for unsaturated soil. Based on the variable structure suction and absorbed suction, the classification of saturation in soil and a principle of narrow sense effective stress are proposed for unsaturated soils. Based on generalized suction, the generalized effective stress formula and a principle of generalized effective stress are proposed for unsaturated soils. The experience parameter χ in Bishop's effective stress formula is defined, and the principal factors influencing effective stress or χ. The primary factor affecting the effective stress in unsaturated soils, and the principle classifying unsaturated soils and its mechanics methods analyzing unsaturated soils are discussed, and this paper points out: The theory on studying unsaturated soil mechanics should adopt the micromechanics method, then raise it to macromechanics and to applying. Researching the mechanical effects of chemical action of water-soil on soil is of great importance to geoenvironmental hazard control. The texture of soil and the fabric of soil mass are set forth. The tests on physical and mechanical property are performed to investigate the mechanism of the positive and negative mechanical effects of different chemical property of aqueous solution. The test results make clear that the plastic limit, liquid limit and plasticity index are changed, and there exists both positive and negative effects on specimens in this test. Based on analyzing the mechanism of the mechanical effects of water-soil interaction on soil, author thinks that hydrochemical actions being provided with mechanical effects on soil comprise three kinds of dissolution, sedimentation or crystallization. The significance of these tests lie in which it is recognized for us that we may improve, adjust and control the quality of soils, and may achieve the goal geological hazard control and prevention.The present and the significance of the research on environmental effects of water-rock and soil interaction. Various living example on geoenvironmental hazard in this field are enumerated. Following above thinking, we have approached such ideals that: ①changing the intensity and distribution of source and sink in groundwater flow system can be used to control the water-rock and soil interaction. ②the chemical action of water-rock and soil can be used to ameliorate the physical and mechanical property of rocks and soils. Lastly, the research thinking and the research methods on mechanical effects and environmental effects of water-rock and soil interaction are put forward and detailed.

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Understanding relationship between environmental protection and economic development is crucial to form practical environmental policy. At micro level, implementation of environmental regulations often causes production mills adjustment of technology which might leads to change of productive efficiency and cost, which, in turn, determine effort level of mills and even local government in pollution control. Using a stochastic frontier production model and a set of survey data on 126 paper mills from six provinces of China, we measure the technical efficiency changes and analyze the determinants of efficiency. in particular, we examine impact of environmental policy on paper mills' efficiency, using an indicator of environmental policy-the levy ratio of COD. We also estimate a simultaneous-equation model in which the levy rate and emission are jointly determined. The results indicate that there have been efficiency improvements during 1999-2003, when enforcement of environmental regulations have been tightened. The impacts, nevertheless, are different for different types of mills. We also find the levy ratio, which is influenced by both the local social and economic conditions and the characters of paper mills, such as scale, has strong impact on the abatement of the pollutant-COD. Additionally, paper mills' technical efficiency has positive effect on the reduction of the emission intensity of the pollutant-COD. These results lead a set of implications pertinent to policy improvement.

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煤作为重要的能源物质,在提供能量的同时,也对生态系统产生巨大的负面效应,尤其在产煤过程中产生的酸性洗煤废水对矿区周边生态环境造成严重破坏.如:波兰奥得河和维斯瓦河的上游因受酸性煤矿废水污染的影响,重金属及氯化物含量超标,大约50%的上游河段未达到水质Ⅲ级标准(Rybicka,1996);美国俄亥俄州霍金河流域受酸性煤矿废水季节性变化的影响,河流生态系统也随之发生改变(Rob-ert等,2001);我国山西省大同市口泉煤矿直接排放的洗煤废水导致附近河流下游断面水质为Ⅴ级,且SO42-、氨氮、Hg、COD和氟化物等超标率很高(时红,2002).…… 煤炭作为重要的能源物质,在提供能量的同时,也对生态系统产生巨大的负面效应,尤其在产煤过程中产生的酸性洗煤废水对矿区周边生态环境造成严重破坏.如:波兰奥得河和维斯瓦河的上游因受酸性煤矿废水污染的影响,重金属及氯化物含量超标,大约50%的上游河段未达到水质Ⅲ级标准(Rybicka,1996);美国俄亥俄州霍金河流域受酸性煤矿废水季节性变化的影响,河流生态系统也随之发生改变(Rob-ert等,2001);我国山西省大同市口泉煤矿直接排放的洗煤废水导致附近河流下游断面水质为Ⅴ级,且SO42-、氨氮、Hg、COD和氟化物等超标率很高(时红,2002).

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本文是以废治废为原则,减少环境污染为目标进行的研究。选取凯里造成纸厂所排出的造纸废水为研究对象,了解该废水的特性及其对巴拉河的污染影响;利用工业固体废弃物硫铁矿烧渣、铝精液或氢氧化铝、工业用水玻璃,工业硫酸研制成功了一类新型号的工业废水处理混凝剂PSAFS(聚硅酸硫酸铝铁),造纸废水经过PSAFS处理后色度,COD、BOD等主要污染物低于国家一级排放标准;处理后废水中金属Pb、Cu、Zn、Gr、As的含量都低于国家地面水Ⅲ类标准。在相同的投加量和混凝时间下,PSAFS混凝剂对造成纸废水的混凝效果比碱式氯化铝(PCA)、硫酸铝、氯化铁的混凝效果好。

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目前在废水处理领域,其处理方法有生物化学法、离子交换法、化学氧化法、电渗析法和混凝沉淀法等,而应用最普遍、并且成本较低的处理方法仍然是混凝沉淀法。它几乎可以用于各种工业废水和城市污水的预处理、中间处理和最终处理,以及污泥处理当中。混凝剂性能是影响混凝沉淀处理效果的关键因素。因此,研制和开发高效能、低毒无公害、低能耗、低成本的新型混凝剂就显得非常重要。我们自行研制成功的聚硅酸铝铁类系列混凝剂(PSAFC、PSAFS、PSAFCS),作为新型的无机高分子复合型混凝剂,属于水溶性无机高分子物质。其实质为铝、铁盐类水解过程的中间产物与硅酸根阴离子等基团的结合体。本文在前人工作的基础上,主要研究了复合型聚硅酸铝铁类混凝剂(PSAFCS)的配制、各类不同配比混凝剂的粘度、ζ电位与混凝效果的关系、以及对印染废水、垃圾渗滤液和造纸废水的静态和动态混凝处理效果等,得到了以下相应的认识和结论。1.在聚硅酸铝铁类混凝剂配制阶段,由于SiO_2的引入将影响混凝剂的聚合度、Zeta电位、存放时间和混凝处理效果等,本论文测定出水玻璃模数K,其值为2.86。而且,硅的存在使混凝剂形态发生了改变,吸附架桥能力增强,增加了混凝剂聚合度,但在某种程度上降低了混凝剂的电中和能力。2.考虑到铝和铁在聚合反应中速度的差异,铁具有极强的亲OH~-能力,能极快地与OH~-形成多羟基聚合物;而铝的亲OH~-能力相对较弱,聚合反应速度缓慢。为了能够使铝盐与铁盐交叉共聚,在配制混凝剂时需采取先加含铝原料,稳定后再加含铁原料的方式。碱化度B是在制备混凝剂时的一个重要操作指标,寻求最佳的碱化度值有利于制备出高效的混凝剂。3. 在PSAFCS中,硫酸根的引入在某种程度上可以增加混凝剂的聚合度和稳定性,增强絮凝能力。并且不同SO_4~(2-)/CI~-比的混凝剂在混凝效果上存在差异。另外,目前市场上工业硫酸与工业盐酸价格相差不大,而工业硫酸的当量数是工业盐酸的1.94倍,故用硫酸代替部分盐酸可降低酸耗成本。4.Ferron逐时络合比色法被广泛应用于铝盐、铁盐溶液的形态分析,并且可得出较好的分析结果。但是在铝铁共存的溶液中进行形态分析,尚有一定困难。5.混凝剂的表观分子量与粘度之间存在着正比关系,通过测定,聚硅酸铝铁类混凝剂的增比粘度随着存放时间有一定的上升趋势,其中硫酸盐型混凝剂(PSAFS)的趋势最明显,存放时间相对较短。盐酸盐型混凝剂(PSAFC)的增比粘度与PSAFS和PSAFCS相比最小。说明其聚合度最小,硫酸根的介入可使聚硅酸铝铁类混凝剂的聚合度增大。比浓粘度与质量浓度之间存在着一定的正相关关系。6. 混凝剂的ζ电位值由于硅的引入而变得有正有负,这与不同类型混凝剂中硅、铝、铁的相对含量有关。一般SiO_2:(Al+Fe)比值大于1:2时,ζ电位为负值。7.系统阐述了PSAFC和PSAFS在印染废水处理中的应用,经过混凝处理的印染废水出水中,残留硅的含量在0.16mg/L~1.68mg/L之间;残留铁的含量在22.4 μg/L~0.52mg/L之间;残留铝的含量在0.1lmg/L~2.60mg/L之间,而且残留铝含量与碱化度B值之间有着很好的负相关关系,即随着混凝剂碱化度值的增大,残留铝含量降低。系列聚硅酸铝铁类混凝剂对印染废水的色度、浊度、COD等都有较好的去除效果。8.第一次把聚硅酸铝铁类混凝剂应用于垃圾填埋场渗滤液的处理上,通过混凝一臭氧氧化处理后,垃圾渗滤液的BOD_去除率达75.4%、COD去除率达70.6%、色度去除率达94%,其出水水质基本接近我国生活垃圾填埋场污染控制标准(GBl6889--1997)二级标准。9.首次在实验室内进行动态模拟实验,我们用自行设计的动态处理装置,选用13号PSAFCS型混凝剂对造纸废水进行试验,混凝剂SiO_2:Al:Fe比值为1:0.75:0.75,ζ电位为10.8毫伏。在最佳水力条件和最佳混凝剂投量的情况下,对造纸废水的COD去除率达92.5%、色度去除率达96.9%,达到国家造纸工业污染物排放一级标准,说明复合型聚硅酸铝铁类混凝剂(PSAFCS)对造纸废水有着优异的去除效果。

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该文首先详细而系统地介绍了一类新型纳米矿物材料——层柱粘土.论文以贵州大方I/S不规则有序间层粘土为例,在采用多种测试手段了解该矿物的组成、结构及性能的基础上,首次对I/S不规则间层粘土进行了较系统的铝、锆、钛的层柱化研究.XRD、HRTEM、FTIR及DTA-TG共同揭示了大方I/S间层粘土是以Rl型为主的I/S不规则有序间层粘土,化学分析数据计算表明结构中的八面体为二八面体,蒙皂石为钠型蒙脱石.通过对大方I/S不规则间层粘土的铝层柱研究发现,较低的初始铝浓度有利于形成较多的Keggin离子,产物层间距可达3.2~3.5nm,N<,2-BET比表面积达110m<'2>/g.首次对I/S不规则间层粘土进行了钻、钛层柱化研究,所获产物层间距都大于铝层柱者,分别为3.3~4.0nm和3.5~4.7nm.文章首次对层柱I/S不规则间层粘土进行了除层间距以外的孔结构、表面酸性、(水)热稳定性和显微形貌的表征.探讨了层与柱之间、颗粒与颗粒之间的排列和连接对层柱产物性能的影响,比较成功地用IR证据解释了层在机理中四面体的反转问题.最后初步试验了层柱I/S不规则间层粘土对水中重金属pb<'2+>和垃圾淋滤液中COD的去除效果,结果表明卫Ti-I/S对Pb<'2+>的吸附容量可达8.39mg/g,对COD的去除率可高达76.71%.