Effective removal of chlorinated organic pollutants by bimetallic iron-nickel sulfide activation of peroxydisulfate

Chlorinated organic pollutants(COPs) have caused serious contaminants in soil and groundwater,hence developing methods to remove these pollutants is necessary and urgent.By a simple hydrothermal method,we synthesized the bimetallic iron-nickel sulfide(FeNiS) particles which exhibited excellent catalytic property of COPs removal.FeNiS was chosen as the peroxydisulfate(PDS) activator to removal COPs including 4-chlorophenol(4-CP),1,4-dichlorophenol(1,4-DCP) and 2,4,6-trichlorophenol(2,4,6-TCP).The results show that FeNiS can efficiently activate PDS to produce sulfate radical(SO_4~(·-)) which plays major role in the oxidative dechlorination and degradation due to its strong oxidizing property and the ability of producing hydroxyl radicals(~·OH) in the alkaline condition.Meanwhile,the Cl-abscised from COPs during the dechlorination can turn into the chlorine radicals and enhance the degradation and cause further mineralization of intermediate products.This bimetallic FeNiS catalyst is a promising PDS activator for removal of chlorinated organics.     

Directional decomposition of some quaternary rare earth sulfides in the electron beam

Lanthanum-transition-metal-silicon sulfide samples of the general formula La₆B₂C₂S₁₄(where B ≡ Fe or Co; C ≡ Fe, Co or Si) have been examined by X-ray diffraction and high resolution electron microscopy (HREM). No evidence of ordering in the crystallographic B or C sites was present in the HREM images. Diffraction patterns of some crystals exhibited a light streaking mainly along [hk0] directions. This has been attributed to a directional decomposition in the electron beam. In the initial stages, the structural decomposition was primarily in the a direction while preferred orientation was maintained in the C direction. Further irradiation of these regions resulted in the complete breakdown of the parent structure and in the subsequent crystallization of lanthanum sulfide and the corresponding transition metal sulfides.     

基于出行目的链的出行生成—分布组合模型分析

目前,我国城市轨道交通客流预测大多采用交通产生、吸引、出行分布、出行方式划分四阶段模型,其中出行生成与分布是方式划分和交通分配的前提,是模型重要的组成部分.在对传统的四阶段模型的分析基础上,结合非集计模型的优点,论文提出了基于出行目的链的出行生成—分布组合模型.模型充分考虑了居民出行链、出行目的等对客流预测的影响,在完善我国轨道交通客流预测理论和方法,提高预测精度等方面具有一定的理论价值和实际意义.     

城市扩张的空间模式研究——以杭州市为例

以杭州市中心城区的多时相TM/ETM+遥感影像为数据源,采用建设用地扩张强度、空间自相关方法等,分析了杭州市1991~2010年间城市扩张的时空特征,并探讨其扩张的空间模式及其演化.结果表明：（1）杭州市城区快速扩展,各街道 乡镇扩张程度存在明显差异;（2）杭州城市扩张的“热点”方位变化大致为：城北-城西-多方位-城东,其变迁规律与杭州城市扩张模式的总体变化规律一致;（3）杭州市城市扩张的空间模式主要有边缘式、填充式、自发式和线性轴状,且随城市演化过程总体遵循以下轨迹：首先,主城表现为边缘式为主、填充式为辅的扩张;其次,外围自发式的扩张形成了副城;接下来主副城都表现为从填充为主、边缘为辅的扩张转变为边缘为主、填充为辅的扩张;而线性轴状扩张是沿交通线发展并贯穿整个城市空间的演化过程.     

Noise mitigation action plan of Pisa civil and military airport and its effects on people exposure

The “Galileo Galilei” airport is a civil and military airport quite close to central Pisa. Although the airport brings benefits in terms of tourism and different types of income, the air traffic growth exacerbates the exposition to aircraft noise. This could significantly affect public health. To this day, a small number of studies takes into account the standard indicators of Europe by considering noise emission data for military aircrafts. We estimated the noise impact produced by the airport and we evaluated the related exposed population by using the Integrated Noise Model (INM). The noise power levels of both commercial and military flights have been considered as an input to the model. Predicted levels were validated by means of a noise-monitoring network. A new tracking system (AirNav Radar) that captures Automatic Identification System (AIS) signals emitted by each aircraft has been used to emulate takeoff and landing procedures. This improves the accuracy of the input to the model. We simulated noise maps for present and future scenarios, including those following the application of noise reduction measures. For each situation, we also estimated the exposure of the population and the percentages of highly annoyed and highly sleep disturbed people. We show the utility of AIS data and their specific elaboration to draw up noise abatement measures in order to reduce the noise impact on population and allow the airport development.     

餐厨垃圾厌氧干发酵产甲烷试验研究

为了探索餐厨垃圾高温干发酵的稳定性运行条件, 采用经三相分离后的餐厨垃圾为原料, 发酵罐污泥为接种污泥, 在高温干式条件下开展连续厌氧发酵产甲烷试验研究. 结果表明, 餐厨垃圾厌氧发酵产甲烷的最佳容积负荷为·(m3·d)-1, 容积产气率为·(m3·d)-1, 原料产气率为·(kg·d)-1, 甲烷体积分数为52.82%. 该厌氧干发酵产甲烷工艺可实现高温度、高含固率且高负荷条件下的稳定运行.     

Low-carbon building assessment and multi-scale input–output analysis

Presented as a low-carbon building evaluation framework in this paper are detailed carbon emission account procedures for the life cycle of buildings in terms of nine stages as building construction, fitment, outdoor facility construction, transportation, operation, waste treatment, property management, demolition, and disposal for buildings, supported by integrated carbon intensity databases based on multi-scale input–output analysis, essential for low-carbon planning, procurement and supply chain design, and logistics management.     

Cluster analysis based on fuzzy equivalence relation

In this paper, a cluster analysis method based on fuzzy equivalence relation is proposed. At first, the distance formula between two trapezoidal fuzzy numbers is used to aggregate subjects' linguistic assessments about attributes ratings to obtain the compatibility relation. Then a fuzzy equivalence relation based on the fuzzy compatibility relation can be constructed. Finally, using a cluster validity index to determine the best number of clusters and taking suitable λ-cut value, the clustering analysis can be effectively implemented. By utilizing this clustering analysis, the subjects' fuzzy assessments with various rating attitudes can be taken into account in the aggregation process to assure more convincing and accurate cluster analysis.     

Serial-batching scheduling with time-dependent setup time and effects of deterioration and learning on a single-machine

This paper deals with serial-batching scheduling problems with the effects of deterioration and learning, where time-dependent setup time is also considered. In the proposed scheduling models, all jobs are first partitioned into serial batches, and then all batches are processed on a single serial-batching machine. The actual job processing time is a function of its starting time and position. In addition, a setup time is required when a new batch is processed, and the setup time of the batches is time-dependent, i.e., it is a linear function of its starting time. Structural properties are derived for the problems of minimizing the makespan, the number of tardy jobs, and the maximum earliness. Then, three optimization algorithms are developed to solve them, respectively.     

中国不同光气候分区地面日光光谱的观测与分析

我国地域辽阔,各地光气候有很大区别,为了扩大和提高太阳能与天然光的利用范围及利用效率,采用一种便携式的光谱扫描仪,对我国不同光气候分区的7个代表性城市(昆明、西宁、北京、深圳、南京、南昌和重庆)一天中不同太阳高度角对应时刻的地面直射日光光谱在380～780 nm可见光谱段进行了跟踪观测,分析了不同光气候分区城市一天中不同太阳高度角对应时刻的日光光谱变化规律,比较了不同光气候分区城市的日光光谱曲线,总结了日光光谱辐射强度的影响因素。分析表明：不同光气候分区城市一天中不同太阳高度角对应时刻的日光光谱辐射强度不同,但日光光谱功率的分布和走向基本一致,总体呈先上升后下降的趋势,最大峰值出现在475 nm附近,380～475 nm之间光谱功率分布曲线出现陡升,475～700 nm之间曲线有下降趋势但基本平稳,＞700 nm曲线出现了反复的较大起伏;不同光气候分区城市的日光光谱功率分布曲线的分布和走向也基本一致,没有明显的与不同光气候分区直接相关的日光光谱功率分布差异性规律;日光光谱辐射强度与太阳高度角和日面状况密切相关。