Polyphenylene sulfide based anion exchange fiber: Synthesis, characterization and adsorption of Cr(VI)

A fibrous strong base anion exchanger (QAPPS) was prepared for the first time via chloromethylation and quaternary amination reaction of polyphenylene sulfide fiber (PPS), and its physical-chemical structure and adsorption behavior for Cr(VI) were characterized by FT-IR, Energy Dispersive Spectrometry, TG-DTG, elemental analysis and batch adsorptive technique, respectively. The novel fibrous adsorbent could effectively adsorb Cr(VI) over the pH range 1-12, the maximum adsorption capacity was 166.39 mg/g at pH 3.5, and the adsorption behavior could be described well by Langmuir isotherm equation model. The adsorption kinetics was studied using pseudo first-order and pseudo second-order models, and the t_1/2 and equilibrium adsorption time were 5 and 20 min respectively when initial Cr(VI) concentration was 100 mg/L. The saturated fibers could be regenerated rapidly by a mixed solution of 0.5 mol/L NaOH and 0.5 mol/L NaCl, and the adsorption capacity was well maintained after six adsorption-desorption cycles.     

水泵系统噪声与振动控制

从水泵系统振动噪声传播途径控制的角度,着重分析了水泵机座二次隔振系统、水泵接管隔振、隔振系统位移限制、管道支架减振、管道穿墙隔振、管道阻尼隔声包扎等水泵系统振动固体传递途径的控制,消除与建筑结构之间的刚性连接。分析了振动噪声空气传播的阻隔与吸收。     

基于大比例尺地形图的抗震规划工作底图缩编研究

工作底图的编制是开展抗震规划的基础工作之一,好的工作底图不仅能突出抗震规划专题信息,更有利于规划成果的应用。本文以1∶5 000地形图缩编成1∶5万抗震规划工作底图为例,分析了规划底图缩编过程中存在的问题,探索了基于AutoCAD、南方Cass软件以及Arcgis的缩编方法,从而有效提高抗震规划的工作效率。     

通信技术在近海环境监测中的应用

本文针对海洋环境监测覆盖面广、站位分散、数据间断和频繁少量的特点以及海洋环境监测自动化、实时化和连续化的发展趋势,提出一种基于水上移动通信和水声通信技术的海底观测链方式,并以海床基监测数据实时传输系统为例,对系统组成、技术特点、技术原理和应用分别阐述,旨在推广通信技术在海洋环境监测领域中的应用。     

种植基地有机磷农药污染土壤的微生物修复

针对我国土壤普遍受到有机磷农药污染的现状,从有机磷农药污染土壤中筛选出降解作用大、生理性状稳定的5种抗性菌株,根据细菌形态观察、生理生化指标检测及16SrDNA基因序列分析,初步确定其生物学分类地位。通过富集培养及固定化技术,分别研究其对甲拌磷、对硫磷、甲基异柳磷和氯氰菊酯等农药的生物降解作用及其影响因素。初步探讨了微生物对甲拌磷农药的降解机理。上述研究结果表明：利用微生物降解农药是一种较有开发前景的有效方法。     

上海市交通干道颗粒物中水溶性无机离子的污染特征

2011年2月至2011年6月在上海市中心城区交通干道区采集29个TSP样品,对颗粒物中水溶性无机离子的化学特征进行了分析比较。结果表明:在9种水溶性无机离子(F-、Cl-、NO3-、SO42-、NH4+、Ca2+、K+、Mg2+和Na+)中,SO42-和NO3-浓度最高,分别占水溶性无机离子总浓度的36.1%和30.6%。颗粒物的阴离子/阳离子比值平均为1.12,相关性方程的斜率K为1.02,说明颗粒物偏酸性。计算的NO3-/SO42-比值的均值为0.85,表明移动排放源(机动车)对颗粒物中水溶性组分的贡献已接近于固定排放源(燃煤)。计算得出硫的转化率(SOR)均值为0.28(0.12～0.51),氮的转化率(NOR)均值为0.19(0.06～0.40),表明二次颗粒物生成是主要来源之一。     

Effects of two forest types on the dynamics of four base cations along with rainfall partitioning in middle subtropical forests北大核心CSCD

盐基离子随穿透雨和树干茎流的迁移成为森林元素输入的重要组成部分.在迁移过程中,冠层淋溶、树干冲刷等改变了盐基离子含量,而不同林型的林冠特征、树皮性质等存在差异,因此盐基离子含量在不同林型中可能存在差异对米槠次生林和杉木人工林穿透雨、树干茎流进行为期4年的监测,对比研究4种盐基离子(K+、Ca2+、Na+、Mg2+)浓度和输入量的动态特征.结果显示:(1)米槠次生林树干茎流Ca2+、Mg2+浓度显著低于杉木人工林而K+浓度显著高于杉木人工林;穿透雨除Na+浓度外均为米槠次生林显著高于杉木人工林.穿透雨和树干茎流Na+浓度林型差异不显著.(2)两种林型盐基离子季节动态变化基本一致,在雨季旱季各有一个峰值,雨季浓度普遍低于旱季.米槠次生林盐基离子浓度稳定性普遍高于杉木人工林.(3)分析盐基离子浓度与降雨强度的关系发现:Ca2+、K+、Mg2+浓度随雨量级的增加而降低,Na+浓度随雨量级的增加而增加.(4)观测期间米槠次生林穿透雨累计输入Ca2+、K+、Mg2+和Na+总量分别为47.97、35.17、7.15和12.94 kg/hm2,树干茎流累计输入Ca2+、K+、Mg2+和Na+总量分别为11.38、6.21、1.54和3.00 kg/hm2;杉木人工林穿透雨累计输入Ca2+、K+、Mg2+和Na+总量分别为47.24、26.63、6.43和11.55 kg/hm2,树干茎流累计输入Ca2+、K+、Mg2+和Na+总量分别为4.11、1.20、0.50和0.83 kg/hm2.米槠次生林的林内雨盐基离子输入量大于杉木人工林.总体而言,米槠次生林比杉木人工林有更高的养分输入,能更好地维持生态系统养分的供应;上述结果有助于进一步认识森林物质随水文过程的流动,可为人工林经营管理提供一定科学基础数据.(图6表1参36)     

河道型水库支流库湾营养盐动态补给过程

河道型水库支流库湾营养盐季节变化直接决定支流藻类群落结构的演替及初级生产力变化过程.为分析三峡水库支流香溪河库湾主要营养盐来源对营养盐季节性变化的影响,基于2010~2011年香溪河库湾野外监测数据,选取干、支流差异显著(P0.01)的常量离子Cl-和Na+作为水团混合示踪离子,采用二元线性混合模型计算不同时期营养盐各来源的贡献率.结果表明,在枯水运行期(11月~次年2月)和汛后蓄水期(9~10月)时,长江干流对支流库湾营养盐贡献率超过75%,干流倒灌为库湾营养盐主要来源;在汛前泄水期(3~5月)和汛期(6~8月)时,干流倒灌和上游来水的贡献率差异缩小,库湾营养盐来源需考虑两者共同的影响,但干流倒灌仍占据优势.上游来水磷营养浓度相对较高,而长江干流氮、硅营养盐浓度较高,不同时期香溪河库湾分层异重流模式不同,库湾营养盐各来源的贡献率也随之改变,因此库湾营养盐在水库不同运行时期呈现出规律性变化.     

Spatiotemporal Evaluation of Simulated Evapotranspiration and Streamflow over Texas Using the WRF‐Hydro‐RAPID Modeling Framework

This study assesses a large‐scale hydrologic modeling framework (WRF‐Hydro‐RAPID) in terms of its high‐resolution simulation of evapotranspiration (ET) and streamflow over Texas (drainage area: 464,135 km²). The reference observations used include eight‐day ET data from MODIS and FLUXNET, and daily river discharge data from 271 U.S. Geological Survey gauges located across a climate gradient. A recursive digital filter is applied to decompose the river discharge into surface runoff and base flow for comparison with the model counterparts. While the routing component of the model is pre‐calibrated, the land component is uncalibrated. Results show the model performance for ET and runoff is aridity‐dependent. ET is better predicted in a wet year than in a dry year. Streamflow is better predicted in wet regions with the highest efficiency ~0.7. In comparison, streamflow is most poorly predicted in dry regions with a large positive bias. Modeled ET bias is more strongly correlated with the base flow bias than surface runoff bias. These results complement previous evaluations by incorporating more spatial details. They also help identify potential processes for future model improvements. Indeed, improving the dry region streamflow simulation would require synergistic enhancements of ET, soil moisture and groundwater parameterizations in the current model configuration. Our assessments are important preliminary steps towards accurate large‐scale hydrologic forecasts.     

镁-钙羟基磷灰石吸附剂对水中Pb2+的去除

选择Mg2+为掺杂离子,通过溶胶-凝胶法制备了不同比例的镁-钙羟基磷灰石吸附剂,研究其对水溶液中Pb~(2+)的去除特性和过程机制.结果表明,吸附剂表面以羟基磷铅矿化合物[Pb10(PO4)6(OH)2]为主,其晶体结构由短棒状转变为针状结构;在温度25℃,p H为5时,镁-钙羟基磷灰石吸附Pb~(2+)在720 min内达到平衡,吸附剂的最佳投加量为0. 6 g·L-1,最大吸附量为813. 17 mg·g-1;热力学实验结果:ΔGθ0、ΔSθ 0和ΔHθ 0,表明镁-钙羟基磷灰石吸附Pb~(2+)的过程是自发的吸热、熵增的过程,升温有利于吸附;吸附过程符合伪二级动力学方程,Langmuir吸附模型能更好地描述等温吸附行为;材料表征与吸附实验分析表明,表面络合与溶解-沉淀是镁-钙羟基磷灰石去除Pb~(2+)的主要机制.