内、外循环EGSB反应器酸碱调控能力的对比试验研究

通过对比运行试验,研究了内、外循环EGSB反应器酸碱特征及其调控能力.结果表明,内、外循环厌氧反应器内部的pH值分布规律相似,较低有机负荷时pH值梯度变化较小,较高负荷时随循环比变化pH值分布有所差别,但2种条件下循环比为3时反应器内pH值均可达到较均衡的分布.相同原水pH值条件下外循环体系pH值要高于内循环体系pH值,2种条件下体系pH值变化趋势较为一致,二者平均差值在0.5个单位左右.循环厌氧反应器系统pH值维持在6.3～6.8可以较好地保障系统正常运行,为了保证此条件,外循环运行方式对原水pH值的极限调节范围是4.5～6.8,内循环运行方式对原水pH值的极限调节范围是5.3～7.2.该成果对于研究和应用内外循环EGSB反应器具有理论参考和实用价值.     

雷州无瓣海桑群落7种元素的生物累积和循环

在雷州市附城镇岚北人工生态恢复的 7a生无瓣海桑群落生物量调查的基础上 ,对所采集的无瓣海桑进行了植物体各组分样品的灰分和元素含量测定与循环分析 ,结果表明 :无瓣海桑植物体不同组分的灰分含量范围为 2 .2 7%～ 2 6 .4 1% ,以细根的含量最高 ,枯枝的含量最低 .植物体各组分中 7种元素质量分数范围分别为K 0 .11%～ 1.5 6 % ,Na0 .11%～ 1.6 6 % ,Ca 0 .2 0 %～ 2 .6 6 % ,Mg 0 .15 %～ 1.5 9% ,Fe 0 .0 4× 10 -3 ～ 9.6 4× 10 -3 ,Zn 0 .0 5× 10 -4～ 1.0 3× 10 -4,Cu0 .16× 10 -5～ 1.5 0× 10 -5.其加权平均的富集系数为 0 .0 5～ 9.70 ,其中Ca >K >Cu >Na >Mg>Zn >Fe .群落现存生物量中的累积储量分别为K 10 9.76gm-2 ,Ca 138.89gm-2 ,Na 86 .5 7gm-2 ,Mg 81.0 7gm-2 ,Fe 13.139gm-2 ,Zn 0 .4 83gm-2 ,Cu 0 .10 8gm-2 .群落 2 0 0 1年的元素存留累积储量分别为Ca4 1.6 8gm-2 ,K 37.2 4gm-2 ,Mg 2 7.33gm-2 ,Na2 5 .5 6gm-2 ,Fe 4 .2 75gm-2 ,Zn 0 .188gm-2 ,Cu 0 .0 39gm-2 .2 0 0 1年归还量分别为Ca 2 8.5 9gm-2 ,K 16 .83gm-2 ,Mg 12 .0 7gm-2 ,Na 11.5 8gm-2 ,Fe 0 .916gm-2 ,Zn 0 .14 1gm-2 ,Cu 0 .0 2 6gm-2 .年吸收量分别为Ca 70 .2 7gm-2 ,K 5 4 .0 7gm-2 ,Mg 39.4 0gm-2 ,Na 37.1     

深圳市局地PM2.5污染事件的时空特征及典型背景环流分析

利用深圳及周边地区22个环保监测站的PM_(2.5)小时数据、深圳市152个高密度(2.5 km×2.5 km)自动气象站及3部边界层风廓线仪的探测数据,分析了深圳市局地PM_(2.5)污染事件的时空变化特征及其背景环流特征.结果表明:深圳市西北角和东北角是局地PM_(2.5)污染最频繁的2个区域,局地污染事件发生次数约占总污染事件次数的40%,每日夜间至次日凌晨是局地污染高发期.各个季节局地PM_(2.5)污染发生的大尺度环流形势不同,春季为变性高压脊配合西南低槽发展型,夏季为热带气旋外围环流影响型,秋季为副高控制下的弱高压脊型,冬季主要为冷锋前、弱高压脊或均压场控制型.局地海-陆、丘陵-平原热力差异造成的局地环流易导致地面弱风和局地辐合的出现,成为诱发局地PM_(2.5)污染的直接原因.     

春季北支脊变化特征及其对中国气候的影响

论文利用NCEP/NCAR再分析资料和中国160个站月降水量和气温资料,通过小波、相关分析等方法,讨论了春季北支脊的变化特征及其对中国同期降水和气温的影响。结果表明：春季北支脊缓慢增强,存在2~3 a和准6 a的周期;纬向位置略向东移,具有准3 a和12 a的周期。春季北支脊偏强（弱）,黄河流域到江南地区的降水量偏少（多）,东北、西南和华南地区的降水量偏多（少）;春季北支脊纬向位置偏东（西）,中国北方大部分地区的降水量偏多（少）,西南和江南大部分地区的降水量偏少（多）;中国大部分地区的升（降）温显著。当春季北支脊纬向位置显著偏东（西）时,且强度偏强（弱）,淮河流域降水偏少（多）,东北、西南和华南地区的降水偏多（少）,中国大部分地区气温明显偏高（低）。通过对相应的环流和物理量场的分析,能较合理地解释中国春季气候异常的原因,对中国短期气候预测有一定帮助。     

长输管道凹陷提压回圆评价方法

为了解决长输管道深凹陷所导致的清管器及内检测器难以通过的工程问题,基于局部提高管道内压可使凹陷回圆、深度减小以达到清管器或检测器可通过深度门槛值的思想,建立了内压作用下管道凹陷回圆过程非线性有限元模型;提出了管道凹陷回圆系数的定义;通过应力应变响应分析对凹陷回圆过程的安全性进行论证;对回圆系数的影响因素进行分析,探讨径厚比、管材、凹陷尺寸、初始内压、回圆压力等参数对回圆系数的影响;基于有限元计算算例,采用非线性回归的方法拟合了凹陷回圆系数工程计算公式。研究结果表明:在极限回圆压力工况下,凹陷回圆过程中管道未发生二次塑性损伤;误差分析显示拟合所得公式预测精度较好,可用于长输管道凹陷的回圆评价。     

THE EFFECTS OF ARTIFICIAL CIRCULATION ON A SMALL NORTHEASTERN IMPOUNDMENT1

ABSTRACT: Artificial circulation was applied at East Sidney Lake, a small, eutrophic impoundment in New York, to improve the water quality of the reservoir and tailwater. Treatment was successful at both reducing the stability of the reservoir and maintaining higher mean oxygen concentrations in the bottom waters. Discharge waters had lower metals and phosphorus concentrations during treatment years. However, vertical temperature differences, although minimal, were still sufficient to permit chemical stratification and some phosphorus release from the sediments. Frequent mixing events during periods of low stability, and runoff from storm events, also appeared to increase transport of phosphorus into the epilimnion. Overall, treatment did not result in decreases in algal populations or improvements in water clarity.     

全球能源消费与CO2排放量

在收集全球能源储量和流通状况的基础上，综述了世界各地区能源消费量和各国人均能源水平，汇总了全球ＣＯ２排放总量及各大洲对全球ＣＯ２排放量的贡献率，到２１００年，全球Ｃ矿量预计将从目前６０亿ｔ／ａ增加到３６０亿ｔ／ａ，同时，旨出１９９６年中世界人口１８．８％的北美、欧洲、日本、ＣＯ２排放３１．６亿ｔ（碳），占全球当年ＣＯ２排放总量的５２．４％。     

The Influence of Synoptic-scale Air Flow and Local Circulation on the Dust Layer Height in the North of the Taklimakan Desert

The present study investigates the influences of synoptic-scale air flows and local wind circulations on the dust layer height (DLH) in the Taklimakan Desert, based on lidar observations performed in the north of the desert in March 2003. The DLH fluctuates approximately every three days between 2500 m (above sea level) and 5000 m, including diurnal variations. Meteorological analyses and numerical simulations show that the three-day fluctuation of DLH corresponds with variations in synoptic-scale air flows over the Taklimakan Desert, and the diurnal variations are linked to downdrafts and updrafts that are formed over the north of the desert as part of local circulations. When strong northerly winds prevail in the upper troposphere and a developed valley wind blows toward the Tienshan Mountains in the lower troposphere, the downdrafts strengthen in the middle troposphere over the north of the desert, lowering the DLH to about 2500 m. In contrast, the DLH rises to about 5000 m when the updrafts develop between strong southerly winds in the upper troposphere and a developed mountain wind blowing from the Tienshan Mountains. Simulations for the local circulation behavior without the presence of the Tienshan Mountains demonstrate that the valley and mountain winds on the southern slope of the Tienshan Mountains control the intensity of the downdrafts and updrafts, thereby influencing the DLH over the north of the Taklimakan Desert.     

A HYDRODYNAMIC MODELING STUDY TO DETERMINE THE OPTIMUM WATER INTAKE LOCATION IN LAKE PALDANG,KOREA1

A three‐dimensional hydrodynamic model was applied to Lake Paldang, South Korea. The lake has three inflows, of which Kyoungan Stream has the smallest flow rate and poorest water quality. Since all drinking water intake stations are located near the confluence of Kyoungan Stream within the lake, this contaminated tributary may have a significant impact on the quality of drinking water sources. The optimum drinking water intake location was determined from the applied model. The model was calibrated and verified using the data measured under different hydrological conditions. The model results were in reasonable agreement with the field measurements in both calibration and verification. The circulation and spreading patterns of the incoming flows in the lake, as well as their composition ratios to the drinking water intakes were determined from the model, and three alternative intake locations were proposed. The simulation results suggested that the horizontal and vertical relocations of the intake aqueduct could significantly decrease the composition ratio of the contaminated water. From this study, it was concluded that the three‐dimensional hydrodynamic model could successfully simulate the temporal and spatial mixing patterns of incoming flows and become a useful tool in determining the optimum water intake location in Lake Paldang.     

基于可持续发展的物流运输绿色化的途径与方法分析——以SHARP公司的绿色运输实践为例

由于物流运输绿色化的目的主要在于通过有效的物流系统的规划与控制,在保证物流服务目标的前提下,尽量地去降低运输中的能量消耗和各种废弃物的排放以及运输工具对道路的占用;因此实践中不仅要贯彻和坚持安全性、及时与准确性、经济效益与环境效益相统一以及人与车辆管理的一体化等四方面的原则,而且还在通过技术进步以切实降低各种运输方式对环境的影响、建立起对汽车驾驶员的培训及绩效管理体系、在城市物流系统的合理规划等几个方面进行努力.