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Evaluation of Bottom Sediment Qualities in Ihetutu Minefield, Ishiagu, Nigeria

Journal of Geoscience and environment Protection 2020年第4期8卷 125-142页

作者： R. Sha’Ato A. G. Benibo A. U. Itodo R. A. Wuana department of Chemistry and Centre for Agrochemical Technology & environmental Research (CATER) Federal University of Agriculture Makurdi Nigeria

Bottom sediment qualities in Ihetutu minefield were assessed to ascertain the impact of Pb-Zn mining activities on the sediments from streams, rivers and ponds in the area. Levels of Cu, Zn, Fe, Ni, Mn, Pb, Cd and Cr and some physico-chemical parameters were measured in bottom sediments taken from four sampling stations (streams/mine pits) within Ihetutu minefield of Ishiagu which receives discharges from mining and human activities, and a control sampling station in Uturu (about 12 km away from study area). The study was conducted in four seasons (Rainy, Late Rainy, Dry, and Late Dry Seasons). Sample digestion was done with a temperature adjustable block digester. Heavy metal analysis was carried out with Flame atomic absorption spectrophotometer (FAAS) while other physico-chemical parameters were determined with standard field and laboratory procedures. Ranges of mean values of results obtained were;pH = 5.81 - 6.44, EC = 269.00 - 1545.00 μS/cm, Cl− = 43.30 - 112.33 mg/kg, alkalinity = 0.70 - 1.25 mg/kg, NO3-?= 5.90 - 7.90 mg/kg, TOC = 0.81 - 1.75 mg/kg, TOM = 1.40 - 3.02 mg/kg, Cu = 4.74 - 50.93 mg/kg, Zn = 26.78 - 57.07 mg/kg, Fe = 1066.19 - 1764.05 mg/kg, Mn = 36.66 - 42.96 mg/kg, Ni = 4.02 - 17.19 mg/kg, Pb = 38.01 - 162.23 mg/kg, Cd = 1.01 - 25.90 mg/kg, and Cr = 1.23 - 1.62 mg/kg. Assessment of heavy metals pollution, using pollution indices revealed that Contamination factor ranged from moderate to very high degree of contamination while pollution load index also showed a deterioration of bottom sediment qualities. Geoaccummulation index indicated moderate to very high pollution, especially with Cu, Zn, Pb, and Cd in the mine pit, while Enrichment factor indicated high enrichments and inputs from anthropogenic sources especially, the Pb-Zn mining activities. pollution of the area by heavy metals was in the order of Fe > Pb > Zn > Mn > Cu > Ni > Cd > Cr. Highest positive correlation (r = 0.992) was between Pb and Cu while the highest negative correlatio

关键词： Anthropogenic Enrichment Mining pollution Sediment

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Development of Re-usable C＋＋ classes for Location Aware Management and control Systems for Shipping Applications

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Journal of marine Science and Application 2012年第4期11卷 504-511页

作者： Dhiren Dave Sanjay Nalbalwar Ashok Ghatol department of Electronics & Telecommunication Engineering Dr. Babasaheb Ambedkar Technological University Lonere 402103 India

Location aware management and location based automation are fast upcoming technologies which are facilitated by availability of reliable, accurate, and cheap global positioning systems and location based services. This paper discusses the development of C＋＋ classes, which may be used for development of software for location aware management and control, specifically in merchant shipping, so as to provide improved safety, increased automation, prevention of pollution and reducing the work burden of the crew. The GPS is used in conjunction with the regionally accessible nested global shorelines （RANGS） dataset for this purpose. The design of two main C＋＋ classes named CShorelines and CGPSInput have been discussed. A control system mandatory on all oil-tankers above 150 GRT （and few other vessels） called ODMCS has been made location aware using the novel software developed and the results obtained have been critically examined and presented.

关键词： GPS Location Aware control ODMCS PANGS

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Dynamic Leveling control of a Wireless Self-Balancing ROV Using Fuzzy Logic controller

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Intelligent control and Automation 2013年第2期4卷 235-243页

作者： Mohammad Afif Ayob Dirman Hanafi Ayob Johari department of Communication Engineering Faculty of Electrical and Electronic Engineering Universiti Tun Hussein Onn Malaysia Batu Pahat Malaysia department of Mechatronic and Robotic Engineering Faculty of Electrical and Electronic Engineering Universiti Tun Hussein Onn Malaysia Batu Pahat Malaysia

A remotely operated vehicle (ROV) is essentially an underwater mobile robot that is controlled and powered by an operator outside of the robot working environment. Like any other marine vehicle, ROV has to be designed to float in the water where its mass is supported by the buoyancy forces due to the displacement of water by its hull. Vertically positioning a mini ROV in centimeters resolution underwater and maintaining that state requires a distinctive technique partly because of the pressure and buoyance force exerted by the water towards the hull and partly because of the random waves produced by the water itself. That being said, the aim of the project is to design and develop a wireless self-balancing buoyancy system of a mini ROV using fuzzy logic controller. A liquid level sensor has been implemented to provide feedback to the controller. A user-friendly graphical user interface (GUI) has been developed for real-time data monitoring as well as controlling the vertical position of the ROV. At the end of the project, the implemented fuzzy control system shows enhanced and better performance when compared with one without a controller, a proportional-derivative (PD) controller, and a proportional-integral-derivative (PID) controller.

关键词： Fuzzy Logic controller ROV Underwater Vehicle Wireless

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A green eco-environment for sustainable development:framework and action

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Frontiers of Agricultural Science and Engineering 2020年第1期7卷 67-74页

作者： Xuejun LIU Wen XU Zhipeng SHA Yangyang ZHANG Zhang WEN Jingxia WANG Fusuo ZHANG Keith GOULDING National Academy of Agriculture Green Development College of Resources and Environmental SciencesChina Agricultural UniversityBeijing 100193China Sustainable Agricultural Sciences department Rothamsted ResearchHarpenden AL52JQUK

Following its 40-year reform and‘Open Door’policy,China has recently proposed a new approach to green development and rural revitalization—the idea of Agriculture Green Development(AGD),with the key feature of creating a green *** this minireview we introduce the definition,theory,framework and major components of a green eco-environment as a key part of the *** define a green eco-environment as including four key elements or measures:(1)a green ecoenvironmental indicator system;(2)environmental monitoring and warning networks;(3)emission standards and environmental thresholds for key pollutants;(4)emission controls and pollution remediation *** have used Quzhou County(a typical county in the center of the North China Plain)as an example to show how detailed air,water and soil monitoring networks,as well as improved farmer practices and pollution control measures(especially ammonia emission mitigation and PM2.5 pollution reduction),can begin to create a green eco-environment in China and that AGD is *** conclude by stressing the need to improve the framework and practice for a green eco-environment,especially the importance of linking proposals and practices for a green eco-environment with the United Nations high priority Sustainable Development Goals.

关键词： monitoring networks environmental thresholds ammonia emission mitigation green ecological environment Quzhou County

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Organotin Compounds in Sediments of Northern Lakes, Egypt

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Journal of environmental Protection 2014年第17期5卷 1654-1666页

作者： Mohamed A. Shreadah Safaa A. Abdel Ghani Hamada B. I. Hawash Asia Abd El Samie Abd El Moniem M. Ahmed National Institute of Oceanography and Fisheries Alexandria Egypt Chemistry department Faculty of Science Alexandria University Alexandria Egypt

This pioneered study is aimed to determine the levels and distributions of organotin compounds (OTCs) in sediment samples collected from five Egyptian lakes located in the southern-eastern Mediterranean Sea. The paper has given an account of and the reasons for the widespread distribution of Tributyltin (TBT) in northern lakes. The percentage of TBT ranged from 4% - 100% OTC revealing recent inputs of TBT. The highest average of TBT (2.84 μg/g Sn dry wt) was measured in lake Edku. Dibutyltin (DBT) was observed at most sampled sites. Relatively higher abundance of DBT was observed in sediments of EL-Burullus (0.69 μg/g Sn dry wt). One of most significant findings to emerge from this study is the absence of any strong and significant correlation between TBT and DBT in sediments from five northern lakes. The absence of such correlation might give a clear evidence that both compounds did not come from the same source. The observed OTC levels indicate some highly localized areas of contamination which are severe enough to cause harmful effects on marine flora and fauna. Except for El-Burllus, Triphenyltin (TPhT) was not measured in sediments of most stations. TPhT was the predominant species in El-Burullus, which indicate a source of pollution mostly originated from industrial and agricultural waste water discharge, organic wastes, commercial fertilizers, chemical wastes and pesticides. The percentages of OTC to total tin ranged from 1% to 35%. El-Brullus, Edku and El-Bardaweel exhibited the highest percentages. As a result of lack of enforcement on the control of OTC, the study has thrown up many questions need further detailed environmental assessment of OTC.

关键词： Organotin Compounds Sediments Lakes Egypt

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Factors affecting flocculation performance of synthetic polymer for turbidity control

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Journal of Agricultural Chemistry and environment 2013年第1期2卷 16-21页

作者： Minyoung Kim Seounghee Kim Jinoh Kim Sukwon Kang Sangbong Lee department of Agricultural Engineering National Academy of Agricultural Science Rural Development Administration (RDA) Suwon Republic of Korea

A multilateral effort into managing nonpoint source pollution from agriculture has gotten much attention for many years. Particularly during the heavy rain season, run-off of turbid water from sloped farmlands, fallow ground and/or unmanaged uplands is deteriorated. Flocculant polymer, commonly used in wastewater treatment facilities, but now exploited to improve control of sediment turbidity by promoting flocculation of particles in construction site. This study used the flocculant polymer to control the discharge of agricultural nonpoint source pollution and focused on the understanding of how soil-water and polymer properties affect flocculation performance. Therefore, a series of flocculation experiments under different conditions was evaluated for better polymer clarification efficiency. Various factors such as flocculant dose, end-over-end inversion of a cylinder, and soil-water properties (pH, NaCl, organic matter) were studied. The effective flocculant dose that fulfilled fast settling rate was 10mg·L-1. Additional findings included that 1) increasing pH decreased the settling rate of soil particle;2) a positive relationship between the percentage of turbidity reduction and a level of salinity in Kaolin suspension was observed, and 3) organic matter in soil solution inhibited PAM adsorption onto soil particles, which caused the reduction of flocculation performance. The findings of this study revealed that flocculant polymer possess good results as a turbidity reducetion measure and couldfurther provide valuable information to make better decision on establishment of Best Management Practice for handling agricultural nonpoint source pollution.

关键词： Agricultural Nonpoint Source pollution Flocculation Synthetic Polymer Turbidity control Soil-Water Properties

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Distribution,enrichment mechanism and risk assessment for fluoride in groundwater:a case study of Mihe-Weihe River Basin,China

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Frontiers of environmental Science & Engineering 2023年第6期17卷 63-83页

作者： Xingyue Qu Peihe Zhai Longqing Shi Xingwei Qu Ahmer Bilal Jin Han Xiaoge Yu College of Earth Science and Engineering Shandong University of Science and TechnologyQingdao 266590China College of Safety and environmental Engineering Shandong University of Science and TechnologyQingdao 266590China College of Computer Science and Engineering Shandong University of Science and TechnologyQingdao 266590China department of Resource and Civil Engineering Shandong University of Science and TechnologyTai'an 271019China

Due to the unclear distribution characteristics and causes of fluoride in groundwater of Mihe-Weihe River Basin(China),there is a higher risk for the future development and utilization of ***,based on the systematic sampling and analysis,the distribution features and enrichment mechanism for fluoride in groundwater were studied by the graphic method,hydrogeochemical modeling,the proportionality factor between conventional ions and factor *** results show that the fluorine content in groundwater is generally on the high side,with a large area of medium-fluorine water(0.5–1.0 mg/L),and high-fluorine water is chiefly in the interfluvial lowlands and alluvial-marine plain,which mainly contains HCO_(3)·Cl-Na-and HCO_(3)^(-)Na-type *** vertical zonation characteristics of the fluorine content decrease with increasing depth to the water *** high flouride groundwater during the wet season is chiefly controlled by the weathering and dissolution of fluorine-containing minerals,as well as the influence of rock weathering,evaporation and *** weak alkaline environment that is rich in sodium and poor in calcium during the dry season is the main reason for the enrichment of ***,an integrated assessment model is established using rough set theory and an improved matter element extension model,and the level of groundwater pollution caused by fluoride in the Mihe-Weihe River Basin during the wet and dry seasons in the Shandong Peninsula is defined to show the necessity for local management measures to reduce the potential risks caused by groundwater quality.

关键词： Groundwater in the Mihe-Weihe River Basin Distribution characteristics of fluorine Factors influencing fluoride Enrichment mechanism of fluorine Hydrogeochemical modeling pollution and risk assessment

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Study of diclofenac removal by the application of combined zero-valent iron and calcium peroxide nanoparticles in groundwater

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Journal of Groundwater Science and Engineering 2021年第3期9卷 171-180页

作者： Wen Liang Nian-qing Zhou Chao-meng Dai Yan-ping Duan Lang Zhou Yao-jen Tu College of Civil Engineering Tongji UniversityShanghai 200092China School of environmental and Geographical Sciences Shanghai Normal UniversityShanghai 200234China department of Civil Architectural and Environmental EngineeringUniversity of Texas at AustinUSA.

Diclofenac(DCF)is one of the most frequently detected pharmaceuticals in groundwater,posing a great threat to the environment and human health due to its *** mitigate the DCF contamination,experiments on DCF degradation by the combined process of zero-valent iron nanoparticles(nZVI)and nano calcium peroxide(nCaO_(2))were performed.A batch experiment was conducted to examine the influence of the adding dosages of both nZVI and nCaO_(2)nanoparticles and pH value on the DCF *** the meantime,the continuous-flow experiment was done to explore the sustainability of the DCF degradation by jointly adding nZVI/nCaO_(2)nanoparticles in the reaction *** results show that the nZVI/nCaO_(2)can effectively remove the DCF in the batch test with only 0.05 g/L nZVI and 0.2 g/L nCaO_(2)added,resulting in a removal rate of greater than 90%in a 2-hour reaction with an initial pH of *** degradation rate of DCF was positively correlated with the dosage of nCaO_(2),and negatively correlated with both nZVI dosage and the initial pH *** order of significance of the three factors is identified as pH value>nZVI dosage>nCaO_(2)*** the continuous-flow reaction system,the DCF removal rates remained above 75%within 150 minutes at the pH of 5,with the applied dosages of 0.5 g/L for nZVI and 1.0 g/L for nCaO_(2).These results provide a theoretical basis for the nZVI/nCaO_(2)application to remove DCF in groundwater.

关键词： Nanoscale zero-valent iron(nZVI) Nano calcium peroxide(nCaO_(2)) Diclofenac Fenton-like reaction Groundwater pollution

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Optimization based accurate scheduling for generation and reserve of power system

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Science China(Technological Sciences) 2012年第1期55卷 223-232页

作者： GAO YunLong PAN JinYan YANG ZiJiang GAO Feng JI GuoLi department of Automation Xiamen University Xiamen 361005 China SKLMS Labo atory Xi＇an Jiaotong University Xi＇an 710049 China College oflnformation Engineering Jimei University Xiamen 361021 China School oflnformation Technology York University Toronto Canada M3J 1P3 Canada

With the improvement of electricity markets,the gradual aggravation of energy shortage and the environment pollution,it is urgent to formulate a new model to precisely satisfy the system demand for energy and ***,power system opti-mization dispatching is always formulated as a discrete-time scheduling *** this paper,we first demonstrate through an example that the upper and lower bounds of spinning reserve offered by a unit,given in the discrete-time model framework as constraints,is *** causes the problem that the reserve delivery obtained by the discrete-time scheduling model cannot be carried out *** the detailed analysis of the ramp rate constraints,it is proved that the reachable upper and lower bounds of spinning reserve in every period can be expressed as functions of two variables,i.e.,generation level of unit at the start and end of this ***,a new method is provided to calculate the upper and lower bounds of spinning reserve which are reachable in ***,a new model based on this proposed method for joint scheduling of generation and reserve is presented,which considers the ability to realize the scheduled energy and reserve *** converts the opti-mization based accurate scheduling for generation and reserve of power system from a continuous-time optimal control prob-lem to a nonlinear programming ***,the proposed model can avoid the difficulties in solving a continu-ous-time optimal control *** on the sequential quadratic programming method,numerical experiments for sched-uling electric power production systems are performed to evaluate the model and the results show that the new model is highly effective.

关键词： power system scheduling continuous-time scheduling model precisely reachable up and down spinning reserve sequentialquadratic programming

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Coping with Climate Change through Air pollution control:Some Legal Initiatives from Malaysia

Coping with Climate Change through Air Pollution Control:Som...

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2012 International Conference on environment,Energy and Biotechnology（ICEEB 2012）

作者： Maizatun Mustafa Sharifah Zubaidah Syed Abdul Kader Azlinor Sufian Legal Practice department Ahmad Ibrahim Kulliyyah of LawsInternational Islamic University Malaysia. Civil Law department Ahmad Ibrahim Kulliyyah of LawsInternational Islamic University Malaysia.

Malaysia is committed to addressing climate change and has taken various initiatives in dealing with the *** the policy level,the policy makers are charged with identifying possible national response strategies to climate change and implementing them through various *** of the focus areas is the regulation of the green house gasses emissions from various sources,including that of industries and motor *** the past years,Malaysia has introduced a number of emission control measures to deal with air pollution,particularly through the enforcement of environmental *** paper sets out a range of existing legal strategies on the control of air pollution from both stationary and mobile *** objective is to identify how air pollution law in Malaysia helps protect air quality as well as contributes to efforts to deal with climate change.

关键词： Climate change,Air pollution,environmental law.

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