阳离子艳红染料的光催化降解

本文研究了以沉淀法制备的TiO2为催化剂，紫外杀菌灯为光源，对阳离子艳红染料进行光催化降解的可行性，结果表明，在实验条件下，本系统对阳离子艳红染料有明显的降解效果，浓度为10mg/L的阳离子艳红染料经过30min的处理，其降解率＞88％，此外，还探讨了溶液初始pH值，催化剂的投加量，光照距离和液层高度等因素对光降解反应的影响。     

DEVELOPMENT OF A FRACTURED MEDIUM FLOW MODEL FOR A WASTE SITE1

ABSTRACT: A three‐dimensional fractured medium flow model was developed for the Bear Creek Valley (BCV) S‐3 site of the Oak Ridge Reservation (ORR) using SWIFT III. The numerical modeling for this site focused on a conceptual model established through the analysis of heterogeneous geologic units and matrix fracture properties of the subsurface in the BCV area. The SWIFT III modeling analysis was based on the previous modeling studies that used MODFLOW and MODPATH. A rigorous calibration was obtained first by comparing simulated results with the existing data on ground water levels and then by comparing pumping test results with the simulated ground water levels. A satisfactory agreement between observed and simulated results was obtained. The calibrated model was used to determine sustained yield from a ground water interceptor trench. Different withdrawal rates were used to simulate the performance of the trench for the sustained withdrawal of ground water.     

Time discounting and the decision to protect areas that are near and threatened or remote and cheap to acquire

Should conservation organizations focus on protecting habitats that are at imminent risk of being converted but are expensive or more remote areas that are less immediately threatened but where a large amount of land can be set aside? Variants of this trade‐off commonly arise in spatial planning. I used models of land‐use change near a deforestation frontier to examine this trade‐off. The optimal choice of where to protect was determined by how decisions taken today accounted for ecological benefits and economic costs of conservation actions that would occur sometime in the future. I used an ecological and economic discount rate to weight these benefits and costs. A large economic discount rate favored protecting more remote areas, whereas a large, positive ecological discount rate favored protecting habitat near the current deforestation frontier. The decision over where to protect was also affected by the influence economic factors had on landowners' decisions, the rate of technological change, and ecological heterogeneity of the landscape. How benefits and costs through time are accounted for warrants careful consideration when specifying conservation objectives. It may provide a niche axis along which conservation organizations differentiate themselves when competing for donor funding or other support.     

总程平衡治理技术处理饮料废水工艺

对可乐废水采用总程平衡治理技术,经调查、试验与计算,对废水实行动态的分流．将占总水量不足２％ 的浓废水进行厌氧处理,去除占ＣＯＤ总量７０％ 以上的污染物,使好氧处理负荷降低．根据费用计算中所作假设,在其它条件不变的情况下,总程平衡治理工艺吨水处理能耗可比常规好氧治理工艺节省４８％ ．     

土壤酸沉降缓冲机制的探讨

选取南方主要酸沉降区土壤作模拟酸雨淋溶实验,分析在酸雨作用下各土壤盐基离子的淋溶特性,硅、铝元素的释放规律及淋出液的 pH值变化特点。在此基础上,对土壤酸沉降的缓冲机制进行了探讨。      

黄河三角洲二元结构与多元可持续发展初探

黄河三角洲由石油资源的开发而兴起,其区位条件和油气资源条件都十分优越,但目前仍处于经济发达地区的低谷区。通过对二元结构系数的定量分析,发现该地区具有明显的复合二元结构特征,即“油地+城乡”,二元结构是制约三角洲持续发展的一个重要限制性因素。目前,石油产业的全面改组改制、优越的外部环境和自身基础条件、东营港扩建及其附属加工制造业基地的立项、综合性交通运输网络体系的形成等都是三角洲全面发展的难得机遇。要实现多元可持续发展的目标,必须转变观念,由“以油建城”到“以港兴城”、大力发展资源深加工工业和具有竞争优势的制造业;构建高效生态农业经济体系;推进城市的“内聚式”发展。     

阳离子交换膜对Cu2+离子交换的动力学及热力学研究

对阳离子交换膜离子交换Cu2+的动力学及热力学现象进行了研究,结果表明:温度25℃,溶液pH=6时,干膜对Cu2+饱和交换容量为0.506 mmol/g;随Cu2+初始浓度的升高,离子交换速率常数随之增加;随温度升高,离子交换速率常数随之增加;随转速升高,离子交换速率常数随之增加;离子交换过程与一级反应速率方程拟合结果良好;△G0<0,表明离子交换反应能自发进行;△H0m>0,表明的交换反应为吸热反应;△S0>0,表明交换反应是熵变增加的反应。     

劳动节约型技术进步下的就业转移

在人均GDP可比水平下,我国农业就业份额远高于同一发展阶段的日本、韩国、台湾省,年均农业就业份额下降速度及人均GDP每增长1 000 GK$农业就业份额下降速度均落后于日本、韩国和台湾省。这表明我国农业就业非农化转移相当缓慢,大大滞后于经济发展。延续发展经济学假设,结合新古典理论分析,表明影响农业就业转移的因素包括:资本增长率、创新强度、技术进步的劳动节约偏向和边际劳动产出递减的倾向。利用我国非农产业数据进行实证检验,表明技术进步的劳动节约偏向是就业转移滞后的深层次原因。     

克百威光催化降解动力学的研究

采用TiO2光催化技术对克百威的降解进行了研究,并系统地考察了催化剂用量,溶液初始pH值,底物浓度,活性氧物种和各种阴阳离子对其降解动力学的影响.用Langmuir-Hinshelwood动力学模型对克百威的光催化降解进行了研究,结果表明,克百威在弱碱性条件下降解速率最快,×OH对克百威降解贡献比约为93.4%,h+和其他ROSs的贡献则相对较小.而水溶液中的阴离子BrO3-和S2O82-对克百威的光催化降解有促进作用,I-则有明显的抑制作用,并且水溶液中的K+,Ca2+,Na+,Mg2+和Cu2+等金属阳离子对克百威的降解也均体现了一定程度的抑制作用.     

北京试点碳市场行业基准值研究——以供热行业为例

以北京试点碳市场的供热行业为例开展行业基准值研究,基于2013～2019年碳试点经核查的热力重点排放企业数据,采取4种基准线情景对北京市热力行业碳排放基准值进行分析,结果表明:随着北京市大气污染治理措施推进,供热行业燃煤清洁化改造基本完成,以2017年为分水岭,供热强度由快速下降过渡到平稳状态,适宜选择更近的历史年份作为分析的基准年,经综合评估基准线数值的先进性,行业配额的盈余程度和配额不足企业比例,建议北京市供热行业基准值取值为63.1kgCO₂/GJ,该基准值比已发布的北京市地方行业能耗限额标准严格,与已发布的北京市供热行业碳排放先进值具有较好一致性;北京市热力行业从历史强度法转变为基准线法后,通过划定统一的基准线,令行业整体配额处于不足状态,公平性相比历史强度法进一步提高,对实现全市双碳目标下热力系统重构具有积极促进作用.