文丘里水膜除尘器除尘脱硫增效技术研究

介绍了三相流化床技术用于文丘里水膜除尘器除尘脱硫增效的原理、工艺流程以及在410t／h锅炉上的工业应用结果。工业运行测试结果表明，其脱硫效率可达85％左右，除尘效率达98％左右。该系统结构简单、运行可靠，具备了工业应用的条件。     

焦化厂生化出水电解脱色工艺及其机理的初步研究

针对焦化废水经萃取（蒸氨）脱酚和生化处理后的出水水质的特点，研究用铝板作为电极电解该废水的脱色效果，研究了废水pH、电解槽电压、时间等因素对其色度去除率的影响。结果表明，最佳工艺参数为：pH=4、电解槽电压=10V、时间=30min，此时色度去除率可达93．6％，COD的去除率也可以达到61．78％。采用GC—MS分析了电解前后废水中的有机物成分，探讨了形成高色度水质的原因、有机物的去除及脱色机理。     

苯酚的超临界水氧化试验

以自建的一套连续式超临界水氧化装置的温度，压力，溶氧量和流量等参数的可控性进行了实验，并在此基础上进行了苯酚的超临界水氧化研究。结果表明：所建立的装置能比较精确控制各种条件参数，是可靠的超临界水氧化试验研究装置。在氧气过量的条件下，停留时间是影响苯酚在超临界水中氧化分解的主要因素，反应的温度和压力升高导致苯致苯酚去除率的增大，只要有足够的氧气，苯酚起始浓度的增加对苯酚的转化率影响不明显，在实验条件下，溶液中苯酚的去除动力学对苯酚是一级，氧气是零级。     

蚯蚓体腔细胞彗星试验检测阿散酸在泥浆体系中降解前后的遗传毒性变化

配制不同浓度的阿散酸标准液,与某养猪场附近的表层土壤混合形成泥浆系统,放在摇床上连续培养30d.在第0、1、2、3、4周取出适量降解液,分别用分光光度法测定阿散酸的降解率;用彗星试验检测降解液对赤子爱胜蚓体腔细胞DNA的损伤.结果表明,阿散酸低浓度时在泥浆体系中能被较快降解,500mg/L的降解率达到了25%;蚯蚓体腔细胞彗星试验表明,所有降解液均具有遗传毒性,可导致蚯蚓体腔细胞DNA明显损伤,与对照相比具有显著性差异(P<0.05).图1表1参17     

Effects of Population Size, Mating System, and Evolutionary Origin on Genetic Diversity in Spiranthes sinensis and S. hongkongensis

Hong Kong once supported more than 109 species of wild orchids, of which approximately 30% were endemic. Most of the local wild orchids have now become rare or endangered. I conducted a comparative study of genetic diversity in two closely related terrestrial orchids, an allotetraploid, Spiranthes hongkongensis , and its diploid progenitor, S. sinensis , to assess the effects of the population bottleneck associated with the origin of the polyploid and to investigate the relationships between number of breeding individuals, mating system, and level of isozyme variation in their populations. Nearly complete genetic uniformity was observed both within and among populations of S. hongkongensis . In contrast, S. sinensis had high levels of genetic variation for all of the genetic parameters examined. Regression analysis of population size and several components of genetic diversity in S. sinensis revealed that, among various measures of within-population variation, the proportion of polymorphic loci ( P ) and average number of alleles per locus ( A ) or per polymorphic locus ( A _p ) were the most sensitive to population size ( R ² = 0.942, p = 0.001; R ² = 0.932, p = 0.002; and R ² = 0.923, p = 0.002 respectively). The highly negative correlation ( r = −0.999, p < 0.01) between population size and the mean frequency of private alleles in pairwise population comparisons, p (1), indicated that population size may also be used to predict the extent of population differentiation caused by random genetic drift. Conservation of genetic diversity in S. sinensis could be maximized by protecting several of both large and small populations, whereas fewer populations may be needed to achieve this goal for S. hongkongensis.     

Distribution and Risk Assessment of Fluoride in Drinking Water in the West Plain Region of Jilin Province, China

The west plain region of Jilin province of northeast China is one of the typical endemic fluorosis areas caused by drinking water for many years. Investigations of hydrogeological and ecoenvironmental conditions as well as endemic fluorosis were conducted in 1998. Results show that the ground water, especially, the water in the unconfined aquifer is the main source of drinking water for local residents. The fluoride concentration in groundwater in the unconfined aquifers is higher than that in the confined aquifer in the west plain of Jilin province. The fluoride concentration in the unconfined aquifer can be used to classify the plain into fluoride deficient area, optimum area and excess area, which trend from west to east. High fluoride (>1.0 mg L(-1)) in drinking water resulted in dental and skeletal fluorosis in local residents (children and pregnant women). There exists a positive correlation between fluoride concentration in the drinking water and the morbidities of endemic fluorosis disease (r1 = 0.781, r2 = 0.872). Health risks associated with fluoride concentration in drinking water are assessed. It has been determined that fluoride concentration in excess of 1.0 mg L(-1) exposes residents to high health risks based on risk identification. The study area is classified into five health risk classes as shown in Figure 4. The risk indexes of this area more than 1.0 are accounted for 68% of the total west plain region.     

序批式生物膜法同步除磷脱氮特性研究

对淹没序批式生物膜法去除有机物和磷及同步部分脱氮的特性进行了研究。其适合的载体装填密度为30％，水力停留时间为9h，其中厌氧3h，好氧6h，进水COD负荷从0．27kg/(m^3.d)到1．32kg/(m^3.d)均可使除磷率达90％以上，脱氮率达50％－60％。淹没式生物膜法除磷脱氮工艺中的优势菌属为假单胞菌属，其次依顺序为气单胞菌属，芽孢杆菌属，微球菌属，硝化矸菌属，生物膜具有生物量大（MLVSS达5531．7mg/L)，脱落污泥含磷量高（达5．67％），沉降性好（SVI为101．7）的特点，污泥产率为0．1996kg干泥／kgCOD。     

海洋纤毛虫实验生态学研究I：不同浓度葡萄糖对种群增长的影响

为揭示不同碳氮比对纤毛虫种群增长的影响以及纤毛虫对碳源和能量来源的选择性 ,利用实验生态学方法 ,对海水养殖水体中 3种常见的纤毛虫原生动物 :扇形游仆虫 (Euplotesvannus)、海洋尾丝虫 (Uronemamarinum)和巨大拟阿脑虫 (Paranophrysmagna)在牛肉浸膏及梯度浓度葡萄糖培养基中的种群增长过程进行了初步的探讨 .数据分析表明 ,在牛肉浸膏培养基中加入不同浓度的葡萄糖对于纤毛虫种群增长影响显著 ,其中在 0 .0 5 gL-1葡萄糖浓度的培养基中 3种纤毛虫种群增长最佳 (P <0 .0 5 ) ,而在 0 .4 gL-1浓度时纤毛虫的生长繁殖均受到高度抑制 (P <0 .0 5 ) .这一结果显示 ,不同C N比对纤毛虫的种群增长有着直接的影响 .图 3表 3参 10     

热带山地雨林土壤球囊霉素的分布特征

球囊霉素(GRSP)作为土壤有机碳的重要组分,对土壤质量和土壤碳库有着重要的指示作用。选择我国保存最完好的热带雨林海南尖峰岭为研究对象,通过不同海拔(300、600、900、1200 m)的样品采集,研究了热带山地雨林丛枝菌根(AM)的重要分泌物球囊霉素的空间分布特征,并结合土壤因子,进一步探讨了其分布机制,旨在阐明球囊霉素对热带山地雨林土壤碳库和土壤质量的贡献,丰富丛枝菌根的功能多样性理论基础。结果表明,4个海拔的植物都具有较高的菌根侵染水平,平均为82.92%。不同海拔间,土壤总提取球囊霉素(T-GRSP)和易提取球囊霉素(EE-GRSP)含量具有相同的变化规律,都在海拔1200 m时最高,显著高于其它3个海拔。尖峰岭T-GRSP的质量分数在1.79-3.11 mg·g^-1之间,平均2.205 mg·g^-1;EE-GRSP则为0.75-1.13 mg·g^-1,平均0.904 mg·g^-1。T-GRSP和EE-GRSP占土壤全碳比值的规律在4个海拔也一致,都是在海拔1200 m时最低。在4个海拔中,T-GRSP和EE-GRSP分别占到土壤全碳质量分数的4.33%-8.87%和1.58%-4.12%。对T-GRSP和EE-GRSP的影响因素分析则表明,土壤全碳、全氮和C/N都影响着GRSP的含量;无论是T-GRSP还是EE-GRSP都随着土壤全碳、全氮和C/N的增大而增加;三者对T-GRSP变异的解释率(63.16%、58.94%和36.05%)要远远高于对EE-GRSP变异的解释率(39.59%、32.19%和19.08%)。但土壤pH则仅影响着EE-GRSP的含量变化,全磷则对T-GRSP和EE-GRSP都没有影响。可见,热带雨林土壤中,GRSP含量较高,对土壤碳库具有重要的贡献,且受到土壤全碳和全氮及二者比例的显著影响。     

不同来源的苏云金芽孢杆菌aiiA基因表达及其抗病性分析

苏云金芽孢杆菌(Bacillus thuringiensis,Bt)aiiA基因所编码的AiiA蛋白是一种内酯酶,可以降解N-乙酰高丝氨酸内酯(N-acyl-homoserine lactones,AHLs),从而减弱致病菌产生的危害.本研究克隆了6株不同来源的苏云金芽孢杆菌aiiA基因,并对来自于苔藓(LLB15)和土壤(LLS9)的BtaiiA基因进行了生物信息学分析.结果表明,AiiA-B15分子量为27.97×103,等电点为4.59;AiiA-S9分子量为28.14×103,等电点为4.32,两者都是亲水性蛋白.AiiA蛋白具有很高的保守性,AiiA-B15和AiiA-S9同源性为90%.进化树结果表明,AiiA-B15与Bacillus thuringiensis subsp.kyushuensis进化距离最近,AiiA-S9与Bacillus cereus进化距离最近.将aiiA-B15基因克隆到pGEX-4T-3表达载体中,构建重组质粒pGEXaiiA-B15,IPTG诱导后可大量表达融合蛋白.对表达的条件进行优化.结果表明,0.6mmol/LIPTG,30℃下诱导3h为最佳诱导条件.致病性检测表明,该融合蛋白对胡萝卜欧文氏软腐病菌具有较强的抗病作用.图13表4参23