基于层次分析法的矿井煤自燃危险性模糊评价

为了能够客观、科学的对煤矿开采过程中煤自燃火灾进行有效的预防,综合运用系统工程理论、层次分析法和模糊数学方法建立了煤自燃的危险性综合评价模型。从"人-机-环-管"系统原理角度出发,建立了多层次的煤自燃危险性评价指标体系,并采用层次法对各层次评价指标的权重进行了计算,确定了5类判断指标用于评价煤自燃的危险等级。并在实践中进行应用,评价结果和煤矿实际开采过程中煤自燃发生情况基本吻合,表明了该模型是合理可行的,能够实现对矿井煤自燃危险性进行评价。     

棱状钻杆应用于松软突出煤层钻进强度匹配研究

为解决棱状钻具的强度匹配问题,应用实体设计和数值分析软件,建立不同结构棱状钻具力学分析模型,对其进行强度分析,优化棱状钻具结构。分析结果表明,常规棱状类钻具整体强度匹配不合理,丝扣位置存在受力薄弱点,安全系数较低且整体分布不均衡。可采取加大接头直径、优化接头及棱边结构、应用摩擦焊接工艺等技术手段提高棱状钻具整体强度;改进后的棱状钻杆,整体安全系数分布均衡、波动小,钻杆整体力学性能得到了有效的提高。通过工程应用,解决了煤矿复杂条件煤层钻孔施工丢钻、断钻频繁的被动局面,平均深度超过了设计深度,钻进效率提高20     

基于多源数据的城市空间活力时空特征分析——以南京市河西、仙林新城为例

采用微信宜出行数据、传统规划数据,探索南京市河西和仙林新城的空间活力时空特征。结果发现:(1)在空间层面,河西呈"东高西低、北高南低"的集聚特征,仙林活力分布与高校区位高度匹配。(2)在时间层面,河西呈"降—升—降—升—降"的波动特征,仙林呈"降—升—平缓"的波动特征。(3)工作日的河西活力集中在居住区,休息日集中在商业区;仙林在工作日和休息日无差异,均分布在高校区及其周边的商业区。     

Effect of chemical dose on phosphorus removal and membrane fouling control in a UCT-MBR

Phosphorus removal was enhanced effectively by dosing aluminum sulfate and effluent phosphorus concentration was lower than 0.5 mg/L. Sludge activity was not inhibited but improved slightly with addition of aluminum sulfate. EPS concentrations both in mixed liquid and on membrane surface were decreased, contributing to the effective mitigation of membrane fouling. To enhance phosphorus removal and make the effluent meet the strict discharge level of total phosphorus (TP, 0.5 mg/L), flocculant dosing is frequently applied. In this study, the performance of aluminum sulfate dosing in a University of Cape Town Membrane Bioreactor (UCT-MBR) was investigated, in terms of the nutrients removal performance, sludge characteristics and membrane fouling. The results indicated that the addition of aluminum sulfate into the aerobic reactor continuously had significantly enhanced phosphorus removal. Moreover, COD, NH₄⁺-N and TN removal were not affected and effluent all met the first level A criteria of GB18918-2002. In addition, the addition of aluminum sulfate had improved the sludge activity slightly and reduced trans-membrane pressure (TMP) increase rate from 1.13 KPa/d to 0.57 KPa/d effectively. The membrane fouling was alleviated attributed to the increased average particle sizes and the decreased accumulation of the small sludge particles on membrane surface. Furthermore, the decline of extracellular polymeric substance (EPS) concentration in mixed sludge liquid decreased its accumulation on membrane surface, resulting in the mitigation of membrane fouling directly.     

基于系统仿真模拟的三峡库区生态承载力分区动态评价

针对现有生态承载力评价研究中时间动态性、空间差异性考虑不足等问题,引入系统动力学(SD)模型,围绕生态承载力关键指标实施三峡库区分单元的系统仿真模拟和预测,整合生态承载力综合评价方法,对不同控制单元承载力状况进行动态评价. 结果表明:①2010年三峡库区生态承载力指数为0.55,为弱可承载状态. 生态承载力限制因素分析显示,长江嘉陵江重庆市辖区控制单元、长江涪陵区万州区控制单元主要受制于资源、环境要素,其他3个控制单元(澎溪河开县控制单元、长江云阳县巫山县控制单元、长江恩施州宜昌市控制单元)主要受制于社会、经济要素. ②现有发展趋势下,2010—2025年三峡库区生态承载力指数为0.48~0.57,呈先增后减的趋势,拐点出现在2015年附近,整体亦处于弱可承载状态. 2015年后,以资源、环境为主要限制因素的2个控制单元生态承载力指数开始逐年下降;以社会、经济为主要限制因素的其他3个控制单元生态承载力指数则呈延续上升态势. ③综合调控方案下,三峡库区生态承载力指数在2015年达到0.60,由弱可承载提升为基本可承载;至2018年,所有控制单元均达到基本可承载,生态承载力指数为0.60~0.76. 可见,综合调控方案对各控制单元人口、经济、环境、资源因素的调控行之有效.      

Whole pictures of halogenated disinfection byproducts in tap water from China’s cities

When bromide/iodide is present in source water, hypobromous acid/hypoiodous acid will be formed with addition of chlorine, chloramine, or other disinfectants. Hypobromous acid/hypoiodous acid undergoes reactions with natural organic matter in source water to form numerous brominated/iodinated disinfection byproducts (DBPs). In this study, tap water samples were collected from eight cities in China. With the aid of electrospray ionization-triple quadrupole mass spectrometry by setting precursor ion scans of m/z 35, m/z 81, and m/z 126.9, whole pictures of polar chlorinated, brominated, and iodinated DBPs in the tap water samples were revealed for the first time. Numerous polar halogenated DBPs were detected, including haloacetic acids, newly identified halogenated phenols, and many new/unknown halogenated compounds. Total organic chlorine, total organic bromine, and total organic iodine were also measured to indicate the total levels of all chlorinated, brominated, and iodinated DBPs in the tap water samples. The total organic chlorine concentrations ranged from 26.8 to 194.0 μg·L^–1 as Cl, with an average of 109.2 μg·L^–1 as Cl; the total organic bromine concentrations ranged from below detection limit to 113.3 μg·L^–1 as Br, with an average of 34.7 μg·L^–1 as Br; the total organic iodine concentrations ranged from below detection limit to 16.4 μg·L^–1 as I, with an average of 9.1 μg·L^–1 as I; the total organic halogen concentrations ranged from 31.3 to 220.4 μg·L^–1 as Cl, with an average of 127.2 μg·L^–1 as Cl.     

上海市交通主干道沿线大气颗粒物及其重金属含量分布特征

采集了上海市交通主干道金沙江路距路肩不同距离（近站位、远站位）近地表大气颗粒物样品24个,使用全谱直流电感耦合等离子光谱仪测定其As、Cr、Cu、Pb、Mn、N i等重金属元素浓度。结果表明,大气颗粒物的质量浓度及其重金属绝对浓度在每个采样点的近站位均高于远站位,而部分大气颗粒物的重金属相对浓度表现为远站位高于近站位;金沙江路沿线由外环到内环方向,大气颗粒物的质量浓度有明显降低的趋势,而大气颗粒物重金属含量具有明显的升高趋势,这与机动车的行驶速度是相关的。     

CDM项目温室气体减排成本的不确定性分析

以清洁发展机制(CDM)为背景,针对计算温室气体排放量和减排成本中存在的不确定性进行了MonteCarlo模拟研究,分析了不确定性变量是如何影响决策变量的.结论是:各类碳排放因子、碳排放量、碳减排成本、减排收益是相互关联而存在连锁影响的,其中的发电碳排放因子和煤炭开采释放的甲烷排放系数是主要的.这为进一步计算或估计存在的风险,从而为参与CDM谈判决策提供重要的决策参考.     

高锰酸钠去除水中苯胺的动力学

研究了高锰酸钠去除水中苯胺的动力学和机理。结果表明:高锰酸钠能快速去除水中的苯胺,其表观动力学方程为r=0.453C_AC_B~(1/2)。反应的速率常数κ与温度T成正相关,其反应的表观活化能为19.136kJ·mol~(-1),指前因子为1165.34mmol~(-1/2)·L~(1/2)·min~(-1)。水中苯胺是被高锰酸根和新生态的氧氧化而去除的。     

一种抗菌生物防护口罩的研制

具有抗菌功能的生物防护口罩对于预防呼吸道传染病的流行、保护人员健康具有重要的意义。本文采用化学键结合的方法将生物抗菌剂ε-聚赖氨酸(ε-PL)固定在聚对苯二甲酸乙二酯(PET)非织造布上并与其它过滤材料复合,采用密合拱型结构设计研制出一种具有抗菌功能的生物防护口罩。实验结果表明,该口罩对菌悬液和微生物气溶胶的抗菌率分别为99.99%和81.9%,且抗菌性能稳定;对颗粒气溶胶和微生物气溶胶的过滤效率分别为99.32%和99.99%,在满足GB19083的基础上具有优良的生物防护性能。