降雨条件下河流冲刷型滑坡的基本特征及滑动机制分析——以四川宣汉樊哙大桥滑坡为例

以宣汉樊哙大桥滑坡为例,分析降雨条件下河流冲刷型滑坡的滑动机制。在对滑坡区的地质条件、滑坡的基本特征和滑坡的变形过程等综合分析的基础上,探讨了降雨条件下河流冲刷型滑坡发育特征及形成机理。分析表明,降水对降雨条件下河流冲刷型滑坡起到了双重作用:一方面,河水对坡脚的浸泡、冲刷;另一方面,强降雨形成的雨水沿着坡面渗入坡体,在滑体与基岩接触面上形成滞水带,受地下水的浸泡泥岩极易软化,强度大幅降低,促使坡体滑动。深入研究樊哙滑坡的基本特征和成灾机制,对西南地区临河型滑坡的预防与治理提供一定的技术支持和借鉴作用。     

基于FPGA的电磁多速率仿真通讯接口研究

针对基于现场可编程门阵列(field-programmable gate array,FPGA )的电磁暂态多速率仿真器的海量计算数据与外部系统通讯问题,研究通过定制化的通讯接口硬件和通讯协议,最大限度地利用电力系统仿真的特点,提升小步长仿真的通讯能力,并对通讯接口的可用性和正确性进行测试验证。结果表明:基于 FPGA 的电磁暂态多速率仿真系统通讯接口克服了多速率仿真的通讯瓶颈,实现了高带宽、高稳定性和低延迟的高效通讯,适用于大规模的电磁暂态多速率仿真计算。     

镜泊湖浮游藻类功能群的演替特征及其影响因素

2013年5月、9月及10月采集了镜泊湖26个位点的浮游藻类,并对所采集的藻类进行了功能群划分.结果显示:镜泊湖的浮游藻类可以分为21个功能群,即C、D、F、G、H1、J、L_O、M、MP、N、P、S1、S2、S_N、T、W1、W2、X1、X2、X3、Y[限于篇幅,各功能群的代表性属（种）和生境特征见表 1].不同时期调查的藻类优势功能群存在明显差异,其中,D（适宜较浑浊的浅水水体）、J（适宜混合型高富营养浅水水体）、MP（适宜扰动频繁的浑浊型浅水水体）、X1（适宜混合程度较高的富营养浅水水体）在三次调查中的优势度均>0.02,成为镜泊湖的绝对优势功能群,镜泊湖藻类优势功能群不同时期的演替规律为5月的D+MP+X1+X2经9月的X1+P+MP+L_O+J转变成10月的X1+P+MP.CCA分析结果显示,镜泊湖藻类功能群分布受水环境因子影响较为明显.整体上,水温、ρ（DO）、SD、EC、ρ（COD_Mn）及ρ（NH₃-N）是影响镜泊湖藻类功能群分布格局的主要因素.      

嘉兴市地表水中兽用抗生素的污染现状调查

建立了适合长三角地区重要生猪养殖基地嘉兴市环境水体中4类(四环素类、磺胺类、大环内酯类、喹诺酮类)共10种常用兽用抗生素同时检测的固相萃取与液相色谱质谱(LC-MS/MS)联用技术,对该地区10个典型村镇河道断面和21个市区主要河网监控断面开展调查.结果表明,村镇河道中抗生素污染严重,10种抗生素总浓度为65.6～467.0 ng.L-1.其中,四环素类和磺胺类浓度分别为40.8～253.0 ng.L-1和未检出～165.0 ng.L-1;大环内酯类和喹诺酮类浓度分别为3.1～14.68ng.L-1和未检出～14.54 ng.L-1.市区河网污染相对较轻,10种抗生素总浓度为20.1～61.2 ng.L-1,其中四环素类浓度为未检出～44.0 ng.L-1;磺胺类、大环内酯类和喹诺酮类浓度则分别低于2.7、6.3和21.6 ng.L-1.     

Starch/polyvinyl alcohol blended materials used as solid carbon source for tertiary denitrification of secondary effluent

Starch/polyvinyl alcohol （PVA） blended materials for using as a solid carbon source （SCS） were prepared by blending PVA and gelatinized starch in an aqueous solution system, in which PVA served as framework material and starch as carbon source. The optimization of starch content and temperature effects were investigated. It was indicated that higher denitrification efficiency could be achieved with more starch in the materials. The average specific denitrification rates were 0.93, 0.66, 0.37 and 0.36 mg/（g·day） corresponding to starch content of 70%, 60%, 40% and 30% respectively at 37℃. The denitrification rates increased when operating temperature was raised from 23℃ to 30℃ and then 37℃. The mechanism of carbon release was analyzed incorporating the experimental results of abiotic release in deionized water. The organic carbon was mainly hydrolyzed by microbes, and the biological release efficiencies were at the range of 89.2% to 96.0%. A long-term experiment with a continuous flow reactor with SCS material containing 70% starch was conducted to gain some experience for practical application. When the influent nitrate concentration was in the range of 35.2 to 39.1 mg/L, hydraulic retention time of 4 hr, and operating temperature of 30℃, a nitrogen removal efficiency up to 94.6% and denitrification rate of 0.217 kg/（m3.day） was achieved. The starch-based materials developed in this study can be used as a solid carbon source for tertiary nitrogen removal from secondary effluent.     

Mesopolymer modified with palladium phthalocyaninesulfonate as a versatile photocatalyst for phenol and bisphenol A degradation under visible light irradiation

A novel versatile photocatalyst, FDU-PdPcS, was prepared by immobilizing palladium phthalocyaninesulfonate (PdPcS) onto the FDU-15 mesopolymer via multi-step chemical modification processes involving chloromethylation of the FDU-15 mesopolymer first with chloromethyl methyl ether, a subsequent amination reaction with ethylenediamine, and finally modification with palladium phthalocyaninesulfonate via ionic interaction. The obtained FDU-PdPcS photocatalyst was characterized by the X-ray diffraction (XRD), UV-Vis spectrosopy and inductively coupled plasma (ICP) techniques. This photocatalyst not only affords a high dispersion of monomeric PdPcS molecules, which may further be stabilized by the π-electron of benzene rings of FDU-15, but also provides a number of diamino groups inside the mesopores, which could be advantageous for the photodegradation of phenolic pollutants. In photodegradation studies of phenolic pollutants, the FDU-PdPcS catalyst exhibited excellent visible light photocatalytic activity and reusability. The photodegradation products of phenol and bisphenol A were investigated by the gas chromatoghraphy-mass spectrometry (GC-MS) technique. The results showed that the photodegradation products were composed of carboxylic acids and CO2. Isopropanol, sodium azide and benzoquinone were used as hydroxyl radical (OH.), singlet oxygen (1O2) and superoxide radical (O2.-) scavengers, respectively. The results suggested that 1O2 and O2. were the prominent active species during the photodegradation process. A possible mechanism for the photodegradation of phenol was also discussed.     

铅污染事故生态环境损失评估——以台州铅蓄电池企业为例

国内铅污染事故频繁发生,造成了严重的生态环境污染和人体健康损害。通过采用市场价值法、人力资本法和恢复费用法,对铅污染的生态环境损失进行了全面评估。以台州典型的铅蓄电池企业为例进行研究,铅污染总损失为121．83万元,其中土壤修复及监测费用占77.1％;人体健康损失占18．9％;农作物种植损失占4．0％。     

新疆喀什三角洲地下水化学特征及演化规律

"水质型"缺水问题严重阻碍着新疆喀什地区经济的发展.为研究位于喀什地区西部的喀什三角洲地下水水化学特征及主要离子来源,于2016年6～10月采集地下水水化学样品402组,地下水氢氧同位素样品114组.综合运用数理统计、Gibbs图、离子比、Schoeller图和水文地球化学模拟等方法,分析了喀什三角洲地下水的水文地球化学特征,探讨了水化学演化规律及主要离子来源.结果表明:①该区地下水中阴离子以SO_4~(2-)为主,其次为Cl-;阳离子以Na+为主,地下水类型以SO4·Cl-Na型为主;②该区地下水离子组分受岩石溶滤作用和蒸发浓缩作用控制.水中离子主要来源于蒸发岩的溶解,其次为碳酸岩的溶解.河流冲积平原潜水受蒸发浓缩作用影响,承压水还受反向阳离子交换作用和混合作用影响;③沿地下水流向,地下水离子组分浓度呈递增趋势,岩盐、白云石和石膏发生溶解,方解石沉淀.     

Accurate prediction of air quality response to emissions for effective control policy design

Designing effective control policy requires accurate quantification of the relationship between the ambient concentrations of O₃and PM_2.5and the emissions of their precursors.However,the challenge is that precursor reduction does not necessarily lead to decreases in the concentrations of O₃and PM_2.5,which are formed by multiple precursors under complex physical and chemical processes;this calls for the development of advanced model technologies to prov...     

Synergetic PM2.5 and O3 control strategy for the Yangtze River Delta, China

PM_2.5 concentrations have dramatically reduced in key regions of China during the period 2013–2017, while O₃ has increased. Hence there is an urgent demand to develop a synergetic regional PM_2.5 and O₃ control strategy. This study develops an emission-to-concentration response surface model and proposes a synergetic pathway for PM_2.5 and O₃ control in the Yangtze River Delta (YRD) based on the framework of the Air Benefit and Cost and Attainment Assessment System (ABaCAS). Results suggest that the regional emissions of NOx, SO₂, NH₃, VOCs (volatile organic compounds) and primary PM_2.5 should be reduced by 18%, 23%, 14%, 17% and 33% compared with 2017 to achieve 25% and 5% decreases of PM_2.5 and O₃ in 2025, and that the emission reduction ratios will need to be 50%, 26%, 28%, 28% and 55% to attain the National Ambient Air Quality Standard. To effectively reduce the O₃ pollution in the central and eastern YRD, VOCs controls need to be strengthened to reduce O₃ by 5%, and then NOx reduction should be accelerated for air quality attainment. Meanwhile, control of primary PM_2.5 emissions shall be prioritized to address the severe PM_2.5 pollution in the northern YRD. For most cities in the YRD, the VOCs emission reduction ratio should be higher than that for NOx in Spring and Autumn. NOx control should be increased in summer rather than winter when a strong VOC-limited regime occurs. Besides, regarding the emission control of industrial processes, on-road vehicle and residential sources shall be prioritized and the joint control area should be enlarged to include Shandong, Jiangxi and Hubei Province for effective O₃ control.