磺胺嘧啶和泰乐菌素对养猪废水硝化作用的差异性影响

养猪废水中高残留抗生素会对废水处理系统中的微生物功能产生影响,而由微生物主导的硝化作用是养猪废水脱氮首要环节。为解析抗生素对养猪废水处理系统中硝化反应的影响机制,选取磺胺嘧啶(SDZ)和泰乐菌素(TYL)为代表性抗生素,对比研究了2种典型抗生素不同暴露水平下养猪废水好氧污泥体系氨氧化和硝化反应的变化规律,并结合扩增子测序分析了2种抗生素对硝化反应功能微生物的影响差异。结果表明,在环境浓度下(100～1 000 μg·L^-1)SDZ和TYL对体系氨氧化速率均具有显著抑制作用且与抗生素暴露浓度正相关,1 000 μg·L^-1浓度抗生素试验组中氨氮去除率最高分别下降72%和65%,同时显著降低了体系中微生物丰富度和多样性,抗生素作用时间的影响大于浓度的影响。相比TYL,SDZ对细菌和氨氧化功能菌群结构产生显著影响。SDZ主要显著抑制了亚硝化单胞菌目(Nitrosomonadales)、亚硝化单胞菌科(Nitrosomonadaceae)和亚硝化单胞菌属(Nitrosomonas)等硝化功能菌群。本研究结果为揭示抗生素的环境效应提供基础数据。     

人体胆汁中微塑料的检测与分析

微塑料(MPs)因其广泛分布及其对自然生态系统的影响而受到越来越多关注,但迄今为止还没有研究报告微塑料在人体胆汁中的暴露,本研究通过对人体胆汁中的微塑料进行定性和定量分析,以期为今后深入探究微塑料与人类疾病的关系提供依据。纳入武汉科技大学附属孝感医院2023年3月—5月确诊为胆囊结石并行腹腔镜下胆囊切除术患者12例,收集患者的胆汁样本作为实验组,以程序空白、实验空白及仪器空白作为对照组,采用热解-气相色谱/质谱(Py-GC/MS)方法检测2组样本中微塑料的种类及含量。在12个胆汁样本中检测到聚氯乙烯(PVC)、聚对苯二甲酸乙二醇酯(PET)、尼龙66(PA66)和聚乙烯(PE)共4种微塑料类型,在单个样本中可检测到1~3种不同的微塑料种类,检测结果阳性率为100%(12/12),其中PVC阳性率为100%(12/12),PA66阳性率为91.66%(11/12),PET阳性率为25.0%(3/12),PE阳性率为8.33%(1/12)。在检测到该塑料颗粒的样本中,PA66含量为(10.36±8.62) μg·g^-1,PVC平均含量为14.53 μg·g^-1,PET平均含量为10.66 μg·g^-1,在唯一检测到PE的样本中,其含量为3.01 μg·g^-1。本研究对人体胆汁中的微塑料进行定性和定量分析,为微塑料与人类疾病的深入探讨提供依据。     

杭嘉湖蚕桑区主要大气氟污染源及治理现状

对杭嘉湖蚕桑区大气氟主要污染源——砖瓦厂氟的排放状况及各种含氟烟道废气治理装置的治理效果进行了较为深入的调查分析,认为砖瓦厂含氟废气不经烟道排放较为严重。目前砖瓦厂所采用的各种含氟废气治理装置中,旋流板塔装置除氟效率较佳,可使废气氟的排放浓度降至5mg/m~3以下,基本上能消除下风向300m以远的大气氟污染对蚕桑的严重危害。     

羊角月芽藻摄取磷形态的动力学研究

将湖水中的磷分成总溶解磷,溶解反应磷,总反应磷、溶解的水解性磷,溶解的光解性磷。研究其在羊角月芽过程中的变化。     

调节细胞通透性促进天蓝色链霉菌蓝色素生物合成

在天蓝色链霉菌分批发酵中，36h时一次加入20mg/L的青霉素，色素浓度和分泌率分别提高了26．2％和39．2％；与一次性添加青霉素相比，分多次添加可使色素浓度再提高9％，但分泌率没有明显变化。DMSO浓度为6g/L时，色素浓工和分泌率较对照分别提高了20．5％和50％；2－50g/L的DMSO对菌体生长没有影响。36h时lg/L的吐温80，色素浓度和分泌率分别提高了16．9％和37．5％，60h时加入0.2g/L浓度的SDS，色素浓度较对照基本相当，但分泌率却提高了16．1％。图4表1参7     

Low uptakes of Cd,Cu, and Zn in Dugesia japonica,a freshwater planarian with higher tolerance to metals

Although a freshwater planarian is proposed as a potential model for studying toxicities of environmental pollutants, they are less sensitive to metal exposures, compared to other freshwater invertebrates. We hypothesised that the metal uptake is low in treated planarians, which may lead to their higher tolerance to metals. The acute toxicities of Cu and Zn to Dugesia japonica were determined. The 24- and 48-h median lethal concentrations were 4.50 and 3.46?mg?L^?1, respectively, for Cu, and 41.97 and 37.79?mg?L^?1, respectively, for Zn. Accordingly, combining with the data on Cd in our previous study, higher tolerance of planarians to metals was revealed. Also, tissue levels of Cd, Cu, and Zn in treated D. japonica were determined, and their dissolved uptake rate constants (k₁) were calculated. Results showed that bioaccumulations of these metals in D. japonica were, indeed, lower than that in other freshwater invertebrates having higher susceptibilities to these metals.     

Effects of different endogenous fungi on the mass loss and nutrient content of leaf litter of Cunninghamia lanceolata北大核心CSCD

To explore the role of endophytic fungi in the decomposition of litter, the endophytic fungi Penicillium sp. strain CG2 (A), Fusarium flavum strain AY13 (B), and Talaromyces strain AJ14 (C) of Cunninghamia lanceolata were added to experimental pots in different forms (mycelium, sterilized fermentation broth, single fungus, and mixed fungi), and a control treatment (CK) was set up (no fungi added). At 10, 30, 60, 90, and 120 days after litter decomposition, a study on the decomposition dynamics of C. lanceolata litter under different treatments was performed. The results showed that the rate of leaf mass loss was the highest in the sterilized fermentation broth treatment A after 120 days, and that there was a significant difference (P < 0.05) between the mycelium treatment AC and the control treatment after 60 days (23.97% higher than the control group). On day 60, the litter carbon content from the mycelium treatment A was significantly different from that of the control (P < 0.05), showing a 16.74% lower value, whereas the litter carbon content of the mycelium treatment B was 21.13% lower than that of the control after 90 days. The nitrogen content of the litters of most mycelium and sterilized fermentation broth treatments was increased compared to that of the control group; there was significant difference (P < 0.05) between the sterilized fermentation broth treatment A and the control (P < 0.05), with a 17.05% higher value than that of the control. Similar to nitrogen, the litter phosphorus content also increased; there was a statistically significant difference between the mycelium treatment A and the control group, with treatment A showing a 46.67% higher value than the control group. The potassium content was 28% lower than that of the control group under the sterilized fermentation broth treatment C, a result that was significantly different from that of the control group (P < 0.05). After treatment for 90 days, the ratio of carbon to nitrogen was the lowest under the treatments with the mycelium A and the mycelium B, with values 25.54% and 25.11% lower than that of the control group, respectively, and a statistically significant difference from that of the control group (P < 0.05). The ratio of carbon to phosphorus was the lowest under the treatment with mycelium A after 60 days, and the result was significantly different from that of the control (P < 0.05), with a 43.05% lower value than the control. Thus, the three endophytic fungi had different effects on the mass loss rate and nutrient content of the litter. The Penicillium sp. strain CG2 (A) had statistically significant effects on the mass loss and nutrient content of leaf litter, which was within the range of fungi fertilizer reference values for the breeding of C. lanceolata. © 2018 Science Press. All rights reserved.     

氢氧化铝废渣处理含氟废水的研究

在一定条件下氢氧化铝废渣活化处理,用于处理５０ｍｇ／Ｌ的含氟废水,投加量为２‰,ｐＨ值为６￣１１,去氟率达９６％。吸附平衡浓度与吸附量关系符合Ｌａｎｇｍｕｉｒ等温式,求出２０．０℃、２５．０℃、３０．０℃时的饱和吸附量和吸附系数。其吸附速度符合鲛岛吸附动力学方程式。     

环境浓度微囊藻毒素-LR对菖蒲无机氮吸收特性的影响

富营养化水体中存在的微囊藻毒素(microcystins, MCs)会对水生植物的营养吸收产生潜在威胁。为探讨MCs对水生植物无机氮吸收的影响,分析不同浓度微囊藻毒素-LR(MC-LR)暴露15 d后挺水植物菖蒲对无机氮的吸收特性及其动力学特征。结果表明,0.001 mg·L^-1 MC-LR暴露条件下,菖蒲根系活力、根系生物量及细胞质膜(PM)H⁺-ATP酶活性均显著增加,MC-LR暴露对菖蒲的NO^-₃-N和NH⁺₄-N吸收均有促进作用;0.01 mg·L^-1 MC-LR暴露条件下,菖蒲根系活力、根系生物量及PM H⁺-ATP酶活性均有一定程度上升,菖蒲对NO^-₃-N的亲和力和吸收潜能下降,但对NH⁺₄-N的吸收速率上升;0.03 mg·L^-1 MC-LR暴露条件下,菖蒲根系活力、根系生物量及PM H⁺-ATP酶活性均显著下降,MC-LR暴露通过降低菖蒲对NO^-₃-N和NH⁺₄-N的亲和力和吸收潜能来抑制其对无机氮的吸收。与NH⁺₄-N相比,0.03 mg·L^-1 MC-LR对NO^-₃-N吸收的抑制作用更强。MC-LR(0.001~0.01 mg·L^-1)暴露对菖蒲NH⁺₄-N吸收有不同程度的促进作用,而0.03 mg·L^-1 MC-LR暴露对菖蒲的NH⁺₄-N和NO^-₃-N吸收均产生明显抑制,对菖蒲生长及其氮的去除能力产生不利影响。