Water Dispatch Model for Middle Route of a South‐to‐North Water Transfer Project in China1

Chang, Jian‐xia, Yi‐min Wang, and Qiang Huang, 2011. Water Dispatch Model for Middle Route of a South‐to‐North Water Transfer Project in China. Journal of the American Water Resources Association (JAWRA) 47(1):70‐80. DOI: 10.1111/j.1752‐1688.2010.00478.x Abstract: The objective of this paper is to present a simulation model to address the water dispatch problem of the south‐to‐north water transfer project for the Middle Route system in China. Reasonable rules and a system network structure are established. This model consists of five modules: (1) a data‐processing module, (2) an initial control module, (3) a multisource simulation dispatch module, (4) a system identification module, and (5) a revision module. Water allocated to each province and city along the route is obtained by simulation, and the long‐term operation results show that water supply reliabilities are significantly improved if the transferred water is jointly dispatched with the local water resources.     

Reliability of solid phase microextraction in estimating bioavailability of pyrene in soil

Solid phase microextraction (SPME) coupled with gas chromatography was employed to estimate bioavailability of pyrene in soils with different properties of textures, organic matter contents (SOM) and aging periods. Experimental results indicated that biodegradation rates increased from 0.10 (sandy loam) to 0.15 (silty loam) microg g-1 hr1. By contrast, biodegradation rate decreased from 0.10(1.3% SOM) to 0.04 (7.6% SOM) microg g-1hr1. The amounts of pyrene biodegraded decreased 27% when SOM was modified from 1.3 to 7.6%, indicating that distributions of pyrene in soils at biodegradation end points were affected by the SOM. Sequestration as measured by sonication extraction had evidently occurred in aged soil samples. SPME measurements slightly overestimated the amount of pyrene degraded by indigenous and seeded microorganisms, in soils with the different properties (correlation coefficient, R2= 0.74). The present study demonstrates that the SPME method can not replace biodegradation tests commonly used for predicting bioremediation efficacy.     

Actinides and decay products in selected produce and bioindicators in the vicinity of a uranium plant

Cypress needles collected at the edge of the Malvési uranium facility (SW France) exhibit enhanced activities of actinides and some decay products (uranium, americium, plutonium, (230)Th, (226)Ra) compared to a remote site. These enhanced activities resulted from the release of U via smokestacks and passive release from former artificial ponds located inside the nuclear site. Enhanced activities are also observed in selected produce (wheat, lettuce, fruits) sampled from the edge of the site. However, excess actinides measured in wheat grains in 2007 are inconsistent with the activities and the uranium ratio measured in the soils. This result suggests that the studied annual crops were contaminated mainly through the short-term release of airborne actinides, and that other transfer pathways, such as, uptake through the roots or adhesion of soil particles, were negligible.     

An independent review and prioritization of past radionuclide and chemical releases from the Los Alamos National Laboratory--implications for future dose reconstruction studies

From 1999 through 2010, a team of scientists and engineers systematically reviewed approximately eight million classified and unclassified documents at Los Alamos National Laboratory (LANL) that describe historical off-site releases of radionuclides and chemicals in order to determine the extent to which a full-scale dose reconstruction for releases is warranted and/or feasible. As a part of this effort, a relative ranking of historical airborne and waterborne radionuclide releases from LANL was established using priority index (PI) values that were calculated from estimated annual quantities released and the maximum allowable effluent concentrations according to The U.S. Nuclear Regulatory Commission (USNRC). Chemical releases were ranked based on annual usage estimates and U.S. Environmental Protection Agency (USEPA) toxicity values. PI results for airborne radionuclides indicate that early plutonium operations were of most concern between 1948 and 1961, in 1967, and again from 1970 through 1973. Airborne releases of uranium were found to be of most interest for 1968, from 1974 through 1978, and again in 1996. Mixed fission products yielded the highest PI value for 1969. Mixed activation product releases yielded the highest PI values from 1979 to 1995. For waterborne releases, results indicate that plutonium is of most concern for all years evaluated with the exception of 1956 when (90)Sr yielded the highest PI value. The prioritization of chemical releases indicate that four of the top five ranked chemicals were organic solvents that were commonly used in chemical processing and for cleaning. Trichloroethylene ranked highest, indicating highest relative potential for health effects, for both cancer and non-cancer effects. Documents also indicate that beryllium was used in significant quantities, which could have lead to residential exposures exceeding established environmental and occupational exposure limits, and warrants further consideration. In part because of the close proximity of residents to LANL, further study of historical LANL releases and the potential impact to public health is recommended for those materials with the largest priority index values; namely, plutonium, uranium, and selected chemicals.     

Prediction of total bed material load for rivers in Malaysia: A case study of Langat,Muda and Kurau Rivers

A soft computational technique is applied to predict sediment loads in three Malaysian rivers. The feed forward-back propagated (schemes) artificial neural network (ANNs) architecture is employed without any restriction to an extensive database compiled from measurements in Langat, Muda, Kurau different rivers. The ANN method demonstrated a superior performance compared to other traditional sediment-load methods. The coefficient of determination, 0.958 and the mean square error 0.0698 of the ANN method are higher than those of the traditional method. The performance of the ANN method demonstrates its predictive capability and the possibility of generalization of the modeling to nonlinear problems for river engineering applications.     

Integrating farming techniques in an ecological matrix model: Implementation on the primrose (Primula vulgaris)

Several studies have proven the importance of field margins in sustaining biodiversity and other work has been done on the effect of field management on field margin flora. However few models have been built to predict the effects of field management on the flora. Our project addresses this need for a model capable of predicting the effect of cropping techniques and their timing on the flora of field margins. Primula vulgaris is a biodiversity indicator, characteristic of undisturbed flora and found in field margins and woodlands: its population has been declining for several years. We created a temporal matrix model of P. vulgaris populations on field margins, taking into account the effects of field, field margin and roadside management based on literature and expert knowledge. We then analysed its sensitivity to demographic parameters by comparing lambda (growth rate) sensitivity and elasticity. We compared the management parameter effect using the relative growth rate of the population after 6 years of simulation. Sensitivity analysis to biological parameters showed the importance of adult survival and seed production and germination. Results show that P. vulgaris is particularly sensitive to broad-spectrum herbicides and that other management techniques like early mowing, scything and scrub-killer (diluted broad-spectrum herbicide or specific herbicide) are less aggressive. Our simulations show that management of cash crops in Brittany is too aggressive for P. vulgaris populations and that 4-5 years of grassland in the adjacent field are necessary to maintain populations.     

Sex pheromone composition and reproductive isolation in two Busseola species (Lepidoptera: Noctuidae) in Kenya

Closely related species provide an interesting and useful model to understand mate communication diversification. Pre-mating isolation is the result of selection processes and is achieved by utilization of different sex pheromones, but also by different ecological and life traits such as geographic distribution, host-plant specialization and allochrony of sexual behavior. Here, we report sex pheromone identifications and pre-mating isolation of two closely related species of stemborers: Busseola segeta and the yet undescribed Busseola nov. sp., developing on different host-plants and in different geographical locations in Kenya. GC–MS analyses showed that the two species produced the same pheromone components, but in slight different ratios. The respective synthetic pheromone mixtures tested in the field were attractive for males of each species. The low inter-specific variation in the pheromone mixture would allow possible interbreeding in case of accidental introduction of both species in the same environment. Under laboratory conditions, allochrony of the mating period is total and might prevent interbreeding if confirmed in natural conditions. This point would ensure the reproductive isolation between the two species in case of modifications of ecological factors. This study and the chemical structures of the identified pheromone components clearly demonstrate that these Busseola species are closely related although they differ in morphology.     

苏北潮滩群落交错带互花米草斑块与土著种竞争关系研究

选取盐城滨海湿地典型滩地（互花米草与碱蓬交错区、碱蓬滩）互花米草斑块,研究互花米草和本地种的生长特征、斑块微生境变化和互花米草与本地种的相对竞争力。结果表明：①和本地土著种碱蓬Suaeda salsa、芦苇Phragmites australis相比,入侵种互花米草Spartina alterniflora能更有效地改善微生境,其发达根系能够提高土壤含水量,互花米草的耐盐特性和泌盐作用能够使得互花米草在高盐度环境中生存,并有效的降低土壤盐度;②在互花米草与碱蓬交错区,从互花米草斑块边缘到中心,碱蓬的长势显著变弱,互花米草的长势显著增强,互花米草与碱蓬的相对竞争力为1.94±0.94,互花米草的竞争能力明显强于碱蓬;③在碱蓬滩,从互花米草斑块边缘到中心,碱蓬、芦苇的长势显著变弱,互花米草的长势显著增强,互花米草与碱蓬的相对竞争力为0.87±0.30,互花米草与碱蓬之间的竞争相对平衡;④因此,互花米草可能通过种间竞争不断侵蚀碱蓬生境,从而取代当地土著植被碱蓬和芦苇。     

缙云山4种森林植被土壤团聚体有机碳分布特征

以重庆市缙云山的竹林、阔叶林、针叶林和针阔叶混交林这4种亚热带森林植被为研究对象,分析不同林分下土壤团聚体及团聚体有机碳在0～20、20～40、40～60和60～100 cm土壤剖面上的分布规律.结果表明,阔叶林土壤 2 mm粒级团聚体含量、平均重量直径(MWD)、几何平均直径(GMD)及 0. 25 mm团聚体含量(R0. 25)均随土层深度的增加而降低,而其他林分在整个土层中则无明显规律.在各土层中,竹林以 2 mm粒级团聚体为主(30. 73%～53. 08%);阔叶林和混交林的2～0. 25 mm粒级团聚体含量较高,为36. 27%～44. 67%和48. 69%～52. 44%;针叶林的优势粒径为2～0. 25 mm和0. 053 mm.总体上,在各土层中,竹林团聚体的MWD、GMD、R0. 25值均高于其他林分,且其分形维数(D)低于其他林分,可见竹林的土壤团聚体稳定性较好.随着土层深度的增加,不同林分(除针叶林外)土壤团聚体有机碳含量逐渐降低,其中竹林团聚体有机碳含量最高,显著高于针叶林和混交林.就不同团聚体粒级而言,4种林分土壤团聚体有机碳在整个土壤剖面上无明显规律,但各土层均以2～0. 25 mm和0. 053 mm粒级团聚体有机碳含量较高.不同林分下土壤团聚体有机碳相对贡献率存在显著差异,其中针叶林中0. 053 mm粒级团聚体有机碳贡献率最高;竹林的 2 mm粒级团聚体有机碳贡献率高达27. 44%～53. 47%;而阔叶林和混交林则以2～0. 25 mm粒级团聚体有机碳贡献率最高.缙云山的4种林分中,竹林的土壤团聚体稳定性较好,而针叶林的较差;在各土层中,竹林土壤各粒级团聚体有机碳含量最高,针叶林最低.     

Study of high-tech process furnace using inherently safer design strategies (I) temperature distribution model and process effect

High-tech industries, such as those producing semiconductor and TFT-LCD (Thin Film Transistor Liquid Crystal Display), have recently become the most important economic activities in Taiwan. Each of these industries has a complete chain of supply from raw material production, production pre-processing, product manufacturing, to waste handling. Any company in the chain is a critical component, since any accidents of fire, explosion, gas leakage, or power outage would cut off the supply chain, causing inability of continuous operation. In industries of semiconductor and TFT-LCD, great amounts of special gases and chemicals with many machinery equipments are used in the production processes. In cases of accidents or improper installation, this chain of supply, from raw material production, preproduction, product manufacturing, to waste handling materials and equipments may cause severe damages or incidents.This study used the existing model of the horizontal furnace to develop a simulation program. The simulation results were consistent with the existing model, and produced even slightly better results on temperature distribution and temperature sensitivity. The simulation model applied on a vertical furnace could provide data on furnace temperature control for industrial use. Meanwhile, this study also deduced actual temperature control and an ISD strategy, which are consistent with design strategy principles.The validation results on the proposed temperature distribution model suggested that the model can be applied in temperature distribution and sensitivity analysis to obtain adjustment and control models for various heating zones. In the case of a single tool, when processing reduction is 60 pieces, switching off the two heating zones can reduce 44% of power output, for a capacity utilization rate of 93.7% for the entire plant. The application of the proposed temperature control model can reduce power consumption by 121.4 kWh. In addition, with the same number of tools, facilities layouts in two cases have an area difference of 41.4775 m², thus shortening the evacuation time for operators. The experimental results proved that the proposed model has realized the ISD principles of intensification, attenuation, and limitation of effects.