活性艳蓝B-RV高效脱色菌筛选及脱色能力研究

从印染厂的沉淀池污泥和污水处理站的曝气池污泥中分离到3株对活性艳蓝B-RV染料脱色能力较高的细菌,编号分别为A,B1,B2,经鉴定分别为产碱菌属(Alcaligenes)、假单胞菌属(Pseudomonas)和克雷伯氏菌属(Klebsiella).探讨了三株菌在不同接种量、温度、pH和培养时间等条件下对活性艳蓝B-RV脱色的情况,并获得了其脱色反应的最适条件,此三株菌在最适条件下脱色率均能达到70%以上。     

ZnO包覆Al_2O_3的制备表征及光催化性能研究

采用化学沉积法制备了ZnO包覆Al2O3光催化剂,并通过X射线衍射(XRD)、扫描电镜(SEM)进行了表征。在自制的光化学反应器中,以中压汞灯作光源,一定浓度的甲基橙为光催化反应模型化合物,研究了光催化剂的活性。考察了甲基橙初始浓度、催化剂加投量、pH值、温度、光照强度、反应液体积等因素对脱色率的影响。实验结果表明,ZnO包覆Al2O3复合光催化剂具有较高的光催化活性。在250W中压汞灯下光照3h,0.10g复合光催化剂能使200mL,10mg/L甲基橙溶液的脱色率达到92.21%。     

长沙市医疗垃圾管理处置状况及特性研究

报道了对长沙市5所医院为期一个月的研究结果，内容包括：医疗垃圾管理处置现状；医疗垃圾类型及产量；门诊人数、住院人数及垃圾量的变化规律；住院病人和门诊病人的垃圾产率及中药渣产率；传染性垃圾与生活垃圾的比例及医疗垃圾的组成，指出了现行医疗垃圾管理处置需要改进和提高之处，为建立长沙市医疗垃圾集中处理示范工程提供了依据。     

双酚A对青岛大扁藻的干扰效应

为了探讨双酚A(bisphenol A,BPA)对海洋微藻的生态毒性效应,实验选择了以青岛大扁藻(Platymonas helgolanidica)作为受试物种,设置6个实验浓度(即0、2、4、6、8、10 mg·L-1)对微藻进行了96 h暴露处理,测定了不同浓度暴露下对青岛大扁藻的生长以及抗氧化系统酶活性等指标。研究结果表明,BPA对青岛大扁藻的96h-EC50为9.32 mg·L-1,属高毒类污染物。青岛大扁藻经过BPA暴露处理后,细胞密度下降,细胞色素含量降低,并且呈现明显的剂量-效应关系;细胞抗氧化系统中超氧化物歧化酶(SOD)、抗坏血酸过氧化物酶(APX)、单脱氢抗坏血酸还原酶(MDHAR)、脱氢抗坏血酸还原酶(DHAR)、谷胱甘肽还原酶(GR)活性均受到干扰。     

滇池外海北岸封闭水域控养水葫芦对水质的影响

在滇池外海北岸污染严重的0.25 km2封闭性蓝藻治理试验示范区内控养水葫芦,以削减富营养化水体内源氮(N)、磷(P)等污染物,探讨有效改善湖泊水质的生物治理措施.6月底按9.30 kg m-2投放水葫芦种苗,控养面积2.51hm2,示范区水面覆盖度为10%.结果显示:水葫芦放养后生长迅速,特别是在7-9月份,最大生长速率达37 2.7 g m-2 d-1;整个植株干物质平均N、P含量分别为23.22 g kg-1和5.03 g kg-1,每t鲜重水葫芦吸收1.63 kg N、0.35 kg P,通过水葫芦种养示范工程,直接由示范工程水域吸收带走N 1.15 t、P 0.25 t;水葫芦生长期间(7-12月),种养区较对照区水体DO、SD和p H均有下降;水葫芦根系具有较好的吸附拦截浮游藻类效果,致使种养区水体TN、TP和CODMn浓度显著高于对照区(P<0.05),并与水体Chl-a浓度显著正相关(P<0.05);水葫芦采收后并未引起二次污染,水质无恶化趋势.综上认为,规模化控养水葫芦可显著削减水体N、P等内源污染负荷,同时对浮游藻类吸附拦截效果明显,可将其滞留于特定水域,又能吸收利用藻类衰亡释放到水体的污染物,减轻外部空白水域水质恶化的压力.     

基于小波变换的山西省PM2.5污染特征及影响因素

基于山西省11城市2015～2019年PM_2.5日均浓度、社会影响因素数据和气象数据,利用小波变换确定PM_2.5浓度周期,通过Spearman相关性和小波相干谱分别探究PM_2.5与社会影响因素和气象因素的关联,确定PM_2.5长短周期管控的主要影响因子.结果表明,2015～2017年山西省PM_2.5浓度年均值呈上升趋势,年均上升率为4.3%, 2018～2019年呈下降趋势,年均下降率为4.2%;ρ(PM_2.5)月均值呈“U”型分布,1月最高(95μg·m^-3), 8月最低(34μg·m^-3),冬季均值约为夏季的2倍;临汾等南部城市ρ(PM_2.5)均值为62μg·m^-3,大同等北部城市均值为45μg·m^-3,空间上呈南高北低.11城市PM_2.5浓度存在显著周期性变化,主要周期包括293 d左右的长周期和27 d左右的短周期.其中...     

Fabrication of PVA/GO Nanofiber Films by Electrospinning: Application for the Adsorption of Cu2+ and Organic Dyes

Journal of Polymers and the Environment - In recent years, the treatment of water pollution has been a challenging and far-reaching topic. In order to improve the adsorption performance of...     

Comparison of macroinvertebrate community structure in urban (Shenzhen City) streams with typical habitat characteristics北大核心CSCD

2020年12月在深圳市城市区域典型生境特征溪流——城市山区源头溪流金龟河、国家地质公园保护区入海溪流杨梅坑河与黑臭水体治理后溪流石溪河,开展底栖动物多样性与生境质量状况取样,通过多元统计分析探明各溪流底栖动物群落结构差异及其主要环境影响因子.结果表明:(1)金龟河底质异质性(SI)最高;杨梅坑河水质最好且流态异质性(Fr)最优,石溪河水质最差且底质异质性(Fr)最低.(2)共采集鉴定大型底栖动物118个分类单元,隶属于3门6纲14目87科.水生昆虫均占绝对优势,其中金龟河67属(81.7%),杨梅坑河62属(95.4%),石溪河12属(52.2%).金龟河中底栖动物Shannon-Wiener多样性指数、改进的Shannon-Wiener多样性指数、Pielou均匀度均高于杨梅坑河与石溪河.(3)金龟河的主要功能摄食类群是滤食者(45.5%),杨梅坑河(38.3%)与石溪河(58.7%)的主要功能摄食类群均为收集者.(4)冗余分析(RDA)结果显示,氨氮、海拔、湿宽、水温、溶氧、底质异质性(SI)、电导率和流态异质性(Fr)为影响深圳市溪流的大型底栖动物群落结构的主要环境因子.研究表明:(1)深圳市的山区溪流可作为深圳市生物多样性保护的重点区域.(2)在城市溪流生态系统中,水环境化学因子并非为主要影响因子,生境多样性发挥了重要作用.(图6表3参43)     

Effects of stand density on understory species diversity and soil anti-scourability of Cupressus funebris plantation in Yunding Mountain,Sichuan, China北大核心CSCD

To protect the ecosystem of barren mountains, massive Cupressus funebris plantations were allowed in hilly areas of the central Sichuan Basin in the late 1980s. In recent years, Cupressus funebris plantations have faced problems such as biodiversity decline and soil erosion. To study the effects of different forest densities on understory species diversity and soil anti-scourability of Cupressus funebris plantations in Yunding Mountain, a typical sampling method was used to investigate the five different forest densities (1 100, 950, 800, 650, and 500 trees/hm2) and to analyze the correlation between the species diversity index, soil anti-scourability, and root index. In total, 176 species from 128 genera and 69 families were recorded in this area. The number of species in the herb layer was higher than that in the shrub layer. The species diversity index of the shrub layer first increased and then decreased with the decrease in stand density; and the species richness index D and Shannon–Wiener diversity index H showed peak values at a density of 650 trees/hm2. The species richness index D, Shannon–Wiener diversity index H, and Simpson dominance index H’ in the herb layer showed a bimodal trend of increasing, then decreasing, increasing again, and finally decreasing with the decrease in stand density; and the peak values were found at the densities of 650 and 950 trees/hm2. When soil anti-scourability decreased with stand density, it showed a trend of increasing and then decreasing, reaching a peak at a density of 650 trees/hm2. The positive correlation between the species richness index and soil anti-scourability was evident. Thus, 650 trees/hm2 is relatively more conducive to the stability of species diversity and soil anti-scourability in cypress plantations. © 2022 Authors. All rights reserved.