湖南武陵山片区乡村转型时空演化特征及其影响因素分析

乡村转型是激发乡村发展活力，实现乡村可持续发展的重要路径。深入开展连片特困地区乡村转型发展研究对推动精准扶贫与乡村振兴有机衔接具有重要意义。通过构建乡村转型评价指标体系，采用均方差决策法、地理探测器等方法，对2006～2016年湖南武陵山片区乡村转型时空演化特征及其影响因素进行研究。研究表明：（1）湖南武陵山片区乡村转型度整体呈现出明显上升态势，乡村转型度较高的县域数量不断增加，乡村转型度较低的县域数量不断减少。（2）乡村转型度高值区主要分布在武陵源区、鹤城区、吉首市、冷水江市等县（市、区），低值区主要分布在片区的东南部和西北部，总体呈现出“中部高、西北-东南低”的空间格局特征。（3）湖南武陵山片区乡村转型空间分异是多种因素综合作用的结果，人均GDP、人均固定资产投资是主导因素，其次是人均地方财政收入、人均社会消费品零售额、人均储蓄存款；各影响因子之间的交互作用对乡村转型空间分异作用力更强。不同区域应合理有序推动乡村转型发展，从而实现精准扶贫与乡村振兴的有机衔接。     

关于建立资源与环境快速反应系统的探讨

本文阐述了国家快速反应系统的概念及其作用。以建立资源与环境快速反应系统为例,说明建立系统的必要性、系统的内容、组成及技术指示。     

Photocatalytic degradation of L-acid by TiO2 supported on the activated carbon

Introduction Aromatic sulfonic acid, which is produced in large amounts in chemical industry since the end of 19th century, has been widely applied in many industrial processes, including the various steps of procedure (Alonso and Barcelo, 2000). Naphthalene- sulfonic acids are of importance as dye intermediates and commonly used in the textile auxiliary industry employing many azo dyes and pigments. Among them, 1-naphthol-5-sulphonic acid (L-acid) is widely used in the printing as the raw ma…     

加热炉炉管穿孔事故处理及原因分析

以一起直接式原油加热炉炉管穿孔事故为例,介绍了事故处理程序,分析了炉管穿孔的原因是由于漏点腐蚀、坑点腐蚀以及炉管管卡损坏导致的,并提出了类似事故防范对策.     

蒙城地震台地磁绝对观测数据处理分析软件

蒙城地震台地磁绝对观测数据主要通过手工方式计算处理,由于内容多而繁琐,很容易出现人为错误,而且工作效率不高。本文介绍了“蒙城地震台地磁绝对观测数据处理分析软件”,该软件将绝对观测日常数据处理工作有效整合,形成了流程,提高了数据处理效率。并能够对数据进行误差统计、趋势分析等,以了解观测资料的实际状况。     

Chemical characterization of fine particles from on-road vehicles in the Wutong tunnel in Shenzhen, China

Vehicle populations in China have been increasing sharply since 1990s. Vehicle emissions including various gaseous pollutants and particulate matter cause deterioration of air quality. However, measurements of particulate mater from on-road vehicles in China are scarcely reported, and thus the chemical compositions of particles emitted from vehicles in China are unknown. In this research, tunnel experiments were performed to measure PM2.5 in the Wutong tunnel, Shenzhen, China. Detailed PM2.5 chemical compositions, with organic compounds determined by GC/MS, in the tunnel were presented. Elemental carbon and organic matter composed 63% and 34% of the total PM2.5 mass in the Wutong tunnel, respectively. Alkanes, PAHs, hopanes, fatty acids, and dicarboxylic acids were the major identified organic compounds, and their source profiles in the PM2.5 in the Wutong tunnel were characterized. The comparisons of our measurements with those in the literature were also made to demonstrate the characteristics of the vehicle source profiles in the Wutong tunnel. The experimental results in this paper can improve understanding of particulate matter emitted from vehicles in China.     

Effects of riboflavin on the phototransformation of benzo[a]pyrene

Riboflavin (Vitamin B2) is a natural dye-sensitizer habitually present in natural waters. Effects of riboflavin as photosensitizer on the transformation of benzo[a]pyrene (BaP) (10 microM) in the aqueous-organic solvent (water/acetonitrile/methanol 50/40/10) were investigated in this study. The photolysis half life of BaP in solution containing 50 microM riboflavin was 5 min, compared to 98 min in the absence of riboflavin. The rate of phototransformation of BaP increased as the concentration of riboflavin was raised from 10 microM to 100 microM under both natural sunlight and UVA irradiation. The half life of BaP in the presence of 50 microM riboflavin was 10.6 min and 43.1 min when exposed to visible range of natural sunlight and UVA irradiation respectively. Riboflavin decomposes under natural sunlight. Lumichrome, a principal photoproduct of riboflavin, was shown to photosensitize BaP under natural sunlight after photolysis of riboflavin. Our study indicated that other photoproducts from riboflavin, such as lumiflavin, were also involved in the phototransformation of BaP under sunlight when riboflavin diminished. The major photoproducts in the photolysis of BaP were identified as 1,6-benzo[a]pyrene-dione, 3,6-benzo[a]pyrene-dione, 6,12-benzo[a]pyrene-dione by using high performance liquid chromatography (HPLC). All these products were detected in the samples which were irradiated under different light sources and in the presence or absence of riboflavin. The possible phototransformation mechanism was discussed.     

Al13形态在混凝中的作用机制

从铝的水解形态转化角度考察了铝盐在高碱度和高有机物浓度水体中的混凝行为.结果表明,铝盐的混凝效能是与混凝过程中的Al₁₃含量成正比.高投药量时氯化铝(AlCl₃)既可以有效调节水体pH值又能在混凝过程中原位水解产生较多的Al₁₃形态,因而混凝效能要高于聚合氯化铝(PACl).在铝盐混凝中,调节pH值到6～7之间可以控制铝形态分布从而达到提高混凝效能和减少残留铝的目的.在调节pH值强化混凝的方法中使用传统铝盐的效果要好于无机高分子絮凝剂.     

烟气自通道向中厅大空间扩散的实验研究

热烟气由单室经通道向中厅大空间溢流是受限空间火灾中重用的排烟通风问题，它在火场新鲜空气补充及火势向未燃区的蔓延过程中起着重要的作用，而且对火灾的监测、扑救及避险逃生有着重要的意义。本文的实验测量了通道向大空间溢流的准稳态温度场和速度场，得到了出口溢流平均速度与火源功率之间的关系式。实验结果表明：通道出口的热烟气溢流可以近似地认为是二维湍浮力射流，采用二维射流模型可以改进已有的烟气溢流计算方法、提高工程计算的准确度，这对火灾安全工程具有实用意义。     

金属系无机抗菌材料研究进展

主要介绍金属系无机抗菌材料。从材料的选择和合成方面,讨论了材料的特性和抗菌功能相结合的途径,归纳出抗菌材料的制备工艺的一般规律,为开发适合我国国情的无机抗菌材料提供思路。