FIELD MEASUREMENT OF FLOW VELOCITIES,SUSPENDED SOLIDS CONCENTRATIONS,AND TEMPERATURES IN LAKE OKEECHOBEE1

ABSTRACT: This paper presents a field investigation of collecting hydrodynamic and sediment data in Lake Okeechobee with analyses examining mechanisms affecting sediment resuspension in the lake. Lake Okeechobee is a large subtropical lake located in south central Florida. Three‐dimensional flow velocities, suspended solids concentrations (SSC), and temperatures at four locations were measured from January 18 to March 5, 2000. Analyses of these data indicate that wind is the dominant factor in driving flow velocities and therefore transporting suspended solids. Wind direction also affects the SSC, especially in the north central and west littoral areas of the lake. The surface and bottom velocity components frequently flow in opposite directions, forming a stratification of the water column and preventing suspended solids from settling out. This retention of SSC in the water column may have a strong impact on the water quality of Lake Okeechobee. This study provides valuable storm event data and mechanism analyses, which will improve our understanding of the transport of suspended solids, thermal exchanges, and flow patterns within Lake Okeechobee.     

我国企业职业安全健康管理体系的建立与发展

随着全球经济一体化的发展,职业安全健康管理体系(OSHMS)成为继ISO9000和ISO14000后,企业持续发展中关注的又一个重要的标准化体系,职业安全健康已经成为当今世界各国日益关注的热点和焦点,我国于1999年10月颁布了《职业安全卫生管理体系试行标准》,通过两年多的实践,职业安全健康管理体系在我国得到了迅速的发展,在促进安全生产,保证本质安全方面起到了积极的作用。     

氧化铝皮带廊粉尘浓度超标原因及对策

分析了山西铝厂氧化铝皮带廓技术改造以后粉尘浓度超标的原因，提出了降低粉尘浓度的对策。     

注册安全工程师与企业安全管理人员现状比较分析

截至2006年11月,我国有22856人获得注册安全工程师执业资格证书,17411人已注册成为注册安全工程师。详细分析我国现有注册安全工程师年龄、工作年限以及学历等基本情况;在辽宁、山东、上海等5省市随机抽取200家企业进行抽样调查,分析我国企业安全管理人员的基本情况,并将二者进行对比。结果表明:注册安全工程师执业资格制度利于选拔优秀的安全管理人才,优化企业安全管理人员队伍,提高安全管理人员素质。     

Differences in the behavior characteristics between Daphnia magna and Japanese madaka in an on-line biomonitoring system

It is important to select suitable organisms to adapt the requirement of di erent environment monitoring purposes. Following our previous study, the behavioral responses of Daphnia magna and Japanese madaka (Oryzias latipes) were investigated and compared under flow-through conditions in an on-line biomonitoring system. The results showed that both D. magna and Japanese madaka had similar biological clock, but the circadian rhythms of Japanese madaka was more clearly recorded than that of D. magna. And the sensitivity of D. magna was about two orders of magnitudes higher than that of Japanese madaka in di erent types of toxic chemicals (dichlorovos, deltamethrin and cadmium chloride). However, when both animals were used in an on-line biomonitoring system, the life span of D. magna was less than 7 days and Japanese madaka could last for more than one month without feeding. Therefore, D. magna was proposed to be a more sensitive bioindicator and was suitable for short term monitoring the pollution events at concentration level closing to the water quality standard, while Japanese madaka was more suitable for the long-term monitoring for accidental discharges.     

长江三角洲顶部冰后期地层的沉积特征

钻探证实,镇江市谏壁镇长江北岸高桥镇北部埋藏硬粘土层,之上为冰后期松散沉积物.沉积物主要为粉砂、粘土质粉砂、砂泥互层,中部局部夹含细砾中细砂,顶部见淤泥质粘土;夹数十层植物炭屑层;以水平纹理为主,局部见小型交错层理、波状层理.表明冰后期以来该地处于水动力较弱的河湖环境,为多期湖沼相沉积夹汊道河流相沉积,局部有海相沉积物加入.根据碳化植物碎屑14C年龄,推测冰后期底界年龄约13 000 aBP,海侵到达该地的时间约为9 000 aBP,海侵最高位时间约为6 500 aBP.冰后期平均沉积速率约为4.9 m/ka,湖沼相3.4～6 m/ka,河流相10～15 m/ka.对全新统的底界年龄和海相层的埋藏深度进行了讨论.     

石化企业现场用火作业的火险隐患及防范措施

分别从可燃气（液）体排放、设备、化验分析、电气设施、消防器材等方面对用火作业过程中的火险隐患进行了分析,提出了用火作业过程中预防火灾发生的具体措施。     

Removal of Methyl Violet from aqueous solutions using poly （acrylic acid.co-acrylamide）/attapulgite composite

The adsorption of Methyl Violet (MV) cationic dye from aqueous solution was carried out by using crosslinked poly (acrylic acid-co-acrylamide)/attapulgite (Poly(AA-co-AM)/ATP) composite as adsorbent. The factors influencing adsorption capacity of the composite such as pH, concentration of the dye, temperature, contact time, adsorbent dosage, ionic strength and surfactant were systematically investigated. The equilibrium data fitted very well to the Langmuir isotherm and the maximum adsorption capacity reached 1194 mg/g at 30°C. The thermodynamic parameters including G0, △H0 and △S 0 for the adsorption processes of MV on the composite were also calculated, and the negative △H0 and △G0 confirmed that the adsorption process was exothermic and spontaneous. The kinetic studies showed that the adsorption process was consistent with the pseudo second-order kinetic model and the desorption studies revealed that the regeneration of the composite adsorbent can be easily achieved.     

炼油厂废渣碱水去除石油类和硫化物的试验研究

通过试验研究,在停留时间为8h左右,生物曝气滤池（BAF）工艺对碱水二级处理效率高,碱水经过处理后,石油类的平均去除率达到89％,硫化物的平均去除率达到99％。研究结果表明,BAF是一种高效的处理方法,适合炼油厂碱水的净化治理。