长江,嘉陵江重庆城区段二维水质对流扩散数学模型

对二水质对流扩散数学模型的有限差分解作了较详细的叙述，同时对距离步长，时间步长计算，网络内水深，流速，横向扩散系数的求取也作了简要介绍。     

南昌地震台地下水位变化异常的分析判别

本篇文章主要通过对南昌台地下水位资料变化的处理分析，利用求地下水水位变化的加速度来判别和分析地震异常，并初步进行试验预报和探索研究。     

埕岛油田浅海石油钻井平台拖航移位隐患分析

胜利作业三号平台是中石化胜利油田分公司钻井工艺研究院和上海交通大学联合设计,青岛北海船厂建造,隶属井下作业公司使用的第一座齿轮齿条升降的自升式浅海钻井平台,该平台钢质非自航,由平台主体、桩腿和桩靴、升降系统3部分组成.平台主体平面形状接近三角形,3根圆柱形桩腿布置在艏、艉,桩靴为正方形.平台主要任务是对水深5～25 m范围内的油井进行修井作业,适用于4 500 m深度井筒.文章对浅海钻井平台拖航中存在的风险进行了分析,提出了应对措施.     

2008年南方低温冰雪灾害对农业的影响及对策

结合参加农业部组织的分省灾害评估调查活动,分析了2008年南方低温冰雪灾害的成因,指出是一系列天文、地球物理和大气环流异常因素构成的复杂灾害链所诱发。论述了低温冰雪灾害对南方农业生产的影响,总结了抗灾和补救的对策与措施。反思灾害中的经验教训,提出应健全预警机制和建立救灾物资储备,加强减灾和应急救援的技术储备,积极探索适合国情的农业灾害保险制度,通过提高公众素质和健全法制实现调动全社会的力量减灾。     

Facile Preparation of Chitosan Films for High Performance Removal of Reactive Blue 19 Dye from Aqueous Solution

This study aimed at finding effective strategies for high-performance removal of reactive blue 19 (RB19) dye from aqueous solution. Chitosan (CS) films had been prepared by using solvent casting with mild drying for this purpose. The CS films were characterized by X-ray diffraction, field-emission scanning electron microscopy, and Fourier transform infrared (FTIR) spectroscopy. The performance of RB19 removal using CS were evaluated by varying contact time, solution pH, initial dye concentration, and adsorbent dosage. Adsorption isotherms, kinetics, and desorption were investigated by batch experiments. Results showed that CS films exhibited the optimal adsorption performance for RB19 removal and high maximum adsorption capacities of RB19, which were 799 and 822.4 mg g^?1 at 20 and 40 °C, respectively. Adsorption kinetic data were well described by the pseudo-second-order kinetic model. FTIR analyses further indicated that interactions between RB19 and the CS film occurred during adsorption. The CS films also exhibited satisfactory desorption of RB19 at about 80 % after 30 min of desorption at pH 11. Our study demonstrated that the CS films can be easily prepared and applied for effective removal of RB19 in treatment of wastewater.     

Estimation of internal radiation dose to the adult Asian population from the dietary intakes of two long-lived radionuclides

Daily dietary intakes of two naturally occurring long-lived radionuclides, 232Th and 238U, were estimated for the adult population living in a number of Asian countries, using highly sensitive analytical methods such as instrumental and radiochemical neutron activation analysis (INAA and RNAA), and inductively coupled plasma mass spectrometry (ICP-MS). The Asian countries that participated in the study were Bangladesh (BGD), China (CPR), India (IND), Japan (JPN), Pakistan (PAK), Philippines (PHI), Republic of Korea (ROK) and Vietnam (VIE). Altogether, these countries represent more than 50% of the world population. The median daily intakes of 232Th ranged between 0.6 and 14.4 mBq, the lowest being for Philippines and the highest for Bangladesh, and daily intakes of 238U ranged between 6.7 and 62.5 mBq, lowest and the highest being for India and China, respectively. The Asian median intakes were obtained as 4.2 mBq for 232Th and 12.7 mBq for 238U. Although the Asian intakes were lower than intakes of 12.3 mBq (3.0 ug) 232Th and 23.6 mBq (1.9 ug) 238U proposed by the International Commission on Radiological Protection (ICRP) for the ICRP Reference Man, they were comparable to the global intake values of 4.6 mBq 232Th and 15.6 mBq 238U proposed by the United Nation Scientific Commission on Effects of Radiation (UNSCEAR). The annual committed effective doses to Asian population from the dietary intake of 232Th and 238U were calculated to be 0.34 and 0.20 microSv, respectively, which are three orders of magnitude lower than the global average annual radiation dose of 2400 microSv to man from the natural radiation sources as proposed by UNSCEAR.     

新乡市冬、春季节PM2.5中水溶性离子及重金属的污染特征与源解析

于2015年12月—2016年1月(冬季,采暖季)和2016年3—4月(春季,非采暖季)在河南新乡采集了125个膜样本,用重量法分析了PM_(2.5)的质量浓度,电感耦合等离子体-质谱分析仪(ICP-MS)分析了20种常见的金属元素,离子色谱(IC)分析了颗粒物中NH_4~+、K~+、Mg~(2+)、Ca~(2+)、Cl~-、NO_3~-、SO_4~(2-)7种水溶性离子,同时结合气象因子与主因子分析法(PCA)对PM_(2.5)进行追因溯源.结果表明:新乡市采暖季和非采暖季PM_(2.5)浓度均值分别为250.17和148.67μg·m~(-3),污染严重;主要金属元素均为Al、Ca、Zn、Fe、Pb,5种元素总共分别占20种金属元素总量的68%和51%;NH_4~+、SO_4~(2-)和NO_3~-占比均超过水溶性盐离子总量的90%.气象条件与地形条件分别对采暖季和非采暖季的PM_(2.5)局地污染有重要影响;PCA结果发现,新乡市采暖季的PM_(2.5)有3个主要来源,分别为燃煤源(31.86%)、农业源/机动车尾气源(19.34%)和土壤/地面扬尘(22.69%);而非采暖季的3个主要来源分别为机动车尾气源/地壳源(41.67%)、煤炭燃烧源/工业排放源(32.20%)及地面扬尘(12.18%).可见煤炭燃烧、机动车尾气排放对新乡市冬、春季大气污染的贡献较大.     

Anoxic phosphorus removal in a pilot scale anaerobic-anoxic oxidation ditch process

The anaerobic-anoxic oxidation ditch (A²/O OD) process is popularly used to eliminate nutrients from domestic wastewater. In order to identify the existence of denitrifying phosphorus removing bacteria (DPB), evaluate the contribution of DPB to biological nutrient removal, and enhance the denitrifying phosphorus removal in the A²/O OD process, a pilot-scale A²/O OD plant (375 L) was conducted. At the same time batch tests using sequence batch reactors (12 L and 4 L) were operated to reveal the significance of anoxic phosphorus removal. The results indicated that: The average removal efficiency of COD, NH₄⁺, PO₄³⁻, and TN were 88.2%, 92.6%, 87.8%, and 73.1%, respectively, when the steady state of the pilotscale A²/O OD plant was reached during 31–73 d, demonstrating a good denitrifying phosphorus removal performance. Phosphorus uptake took place in the anoxic zone by poly-phosphorus accumulating organisms NO₂⁻ could be used as electron receptors in denitrifying phosphorus removal, and the phosphorus uptake rate with NO₂⁻ as the electron receptor was higher than that with NO₃⁻ when the initial concentration of either NO₂⁻ or NO₃⁻ was 40 mg/L.     

超临界二氧化碳流体萃取土壤中有机污染物的研究进展

就近年来人们利用超临界二氧化碳流体对有机污染物污染的土壤所做的研究工作以及所取得的成果进行了总结。     

利用计算流体动力学(CFD)方法研究电收尘器斜向气流分布

在讨论了电收尘器电场内气流分布对除尘效率影响的基础上,介绍有效降低粉尘返流损失,提高电收尘效率的斜向气流技术,进而利用CFD方法对电场内的气流分布进行数值模拟,给出了在电场内实现斜向气流分布时气流分布板结构调整方法和参数。