期刊文献+
共找到8篇文章
< 1 >
每页显示 20 50 100
Study on a New Technique of On-line Monitoring of Oil Contamination Level Using Computer Vision Technology
1
作者 TUQun-zhang ZUOHong-fu 《International Journal of Plant Engineering and Management》 2004年第2期103-109,共7页
In this paper, a new technique of capturing the images of debris inlubrication or hydraulic oil using micro-imaging and computer vision techniques is introduced. Byway of image processing, the size and distribution of... In this paper, a new technique of capturing the images of debris inlubrication or hydraulic oil using micro-imaging and computer vision techniques is introduced. Byway of image processing, the size and distribution of debris are obtained, and then the oilcontamination level is also obtained. Because the information of oil contamination is obtaineddirectly from the images of debris by this method, the monitoring result is more intuitive andreliable. 展开更多
关键词 hydraulic fluid contamination level micro-imaging image processing
下载PDF
Q-Learning-Based Pesticide Contamination Prediction in Vegetables and Fruits 被引量:1
2
作者 Kandasamy Sellamuthu Vishnu Kumar Kaliappan 《Computer Systems Science & Engineering》 SCIE EI 2023年第4期715-736,共22页
Pesticides have become more necessary in modern agricultural production.However,these pesticides have an unforeseeable long-term impact on people's wellbeing as well as the ecosystem.Due to a shortage of basic pes... Pesticides have become more necessary in modern agricultural production.However,these pesticides have an unforeseeable long-term impact on people's wellbeing as well as the ecosystem.Due to a shortage of basic pesticide exposure awareness,farmers typically utilize pesticides extremely close to harvesting.Pesticide residues within foods,particularly fruits as well as veggies,are a significant issue among farmers,merchants,and particularly consumers.The residual concentrations were far lower than these maximal allowable limits,with only a few surpassing the restrictions for such pesticides in food.There is an obligation to provide a warning about this amount of pesticide use in farming.Previous technologies failed to forecast the large number of pesticides that were dangerous to people,necessitating the development of improved detection and early warning systems.A novel methodology for verifying the status and evaluating the level of pesticides in regularly consumed veggies as well as fruits has been identified,named as the Hybrid Chronic Multi-Residual Framework(HCMF),in which the harmful level of used pesticide residues has been predicted for contamination in agro products using Q-Learning based Recurrent Neural Network and the predicted contamination levels have been analyzed using Complex Event Processing(CEP)by processing given spatial and sequential data.The analysis results are used to minimize and effectively use pesticides in the agricultural field and also ensure the safety of farmers and consumers.Overall,the technique is carried out in a Python environment,with the results showing that the proposed model has a 98.57%accuracy and a training loss of 0.30. 展开更多
关键词 Pesticide contamination complex event processing recurrent neural network Q learning multi residual level and contamination level
下载PDF
Spectrochemical Analysis of Bottled and Tap Water from Selected Counties of Middle Tennessee, USA
3
作者 Aminul Islam Chowdhury Ravneet Kaur +2 位作者 Anonya Akuley-Amenyenu Abua Ikem Sam O. Dennis 《Journal of Water Resource and Protection》 2021年第1期20-31,共12页
A total of 37 elements were determined in tap and bottled water samples from six counties of Middle Tennessee (USA) by Inductively Coupled Plasma Optical Emission Spectrometry (ICP-OES). The overarching goal of the st... A total of 37 elements were determined in tap and bottled water samples from six counties of Middle Tennessee (USA) by Inductively Coupled Plasma Optical Emission Spectrometry (ICP-OES). The overarching goal of the study is to dispel the myth that bottled water is better than tap water or vice versa. Other parameters analyzed were pH, conductivity, and Total Dissolved Solids (TDS). The results were compared with the Maximum Contaminant Limit (MCL) reported by the US Environmental Protection Agency (US-EPA). The concentrations of phosphorus, silicon, fluoride, and chloride conformed to the established values by US-EPA maximum contaminant level corresponding value. The level of Aluminum (Al), Boron (B), Chromium (Cr), Cobalt (Co), Copper (Cu), Iron (Fe), Lithium (Li), Manganese (Mn), Nickel (Ni), Titanium (Ti), Vanadium (V), and Zinc (Zn) conformed to the established values by governmental agencies (USEPA). Heavy metals such as Arsenic (As), Cadmium (Cd), Cobalt (Co), Lead (Pb), Mercury (Hg), and Silver (Ag) were detected in the tap water of the urban (Davidson) and urbanizing (Rutherford and Williamson) counties;suggesting that rural counties had a less heavy metal concentration in their drinking water sources than urban counties (P < 0.05). However, the values were below the Maximum Contaminant Levels (MCLs). 展开更多
关键词 Heavy Metals FLUORIDE ICP-OES Maximum Contaminant level (MCL) Principal Component Analysis (PCA) Cluster Analysis
下载PDF
Analysis of Nitrates and Nitrites in Groundwater of Ilorin Environs
4
作者 Oluwadurotimi O. Akiwumi Omodele. A. Eletta Oluyemi Odebunmi 《Journal of Environmental Science and Engineering(A)》 2012年第5期656-662,共7页
The levels of nitrates and nitrites in drinking water from two local government areas in Ilorin, Kwara State were determined using HACH DR/EL 5 Spectrnphotometer over a period of four months. The average mean concentr... The levels of nitrates and nitrites in drinking water from two local government areas in Ilorin, Kwara State were determined using HACH DR/EL 5 Spectrnphotometer over a period of four months. The average mean concentration of nitrate (NO3-N) in borehole is 0.185 mg/L and for nitrites (NO2-N) is 0.044 mg/L. The mean concentration in well for the nitrate (NOs-N) is 0.915 mg/L and for nitrites is 0.087 mg/L. The observed means as well as the highest single-point values for both nitrates and nitrites in groundwater are well below WHO (World Health Organisation) MCL (maximum contaminant level) of 10.0 mg/L nitrate as NO3-N and 3.0 mg/L nitrite as NO2-N. The values are also below the NSDWQ's (Nigerian Standard for Drinking Water Quality) maximum permitted level of 50 mg/L nitrate as NO3-N and 0.2 mg/L nitrite as NO2-N. 展开更多
关键词 NSDWQ METHEMOGLOBINEMIA BOREHOLES wells MCL (maximum contaminant level).
下载PDF
Advancing Evaluation of Microplastics Thresholds to Inform Water Treatment Needs and Risks 被引量:1
5
作者 Omar S.Chowdhury Philip J.Schmidt +1 位作者 William B.Anderson Monica B.Emelko 《Environment & Health》 2024年第7期441-452,共12页
Although human health impacts of microplastics are not well understood,concern regarding chemical contaminants retained on or within them is growing.Drinking water providers are increasingly asked about these risks,bu... Although human health impacts of microplastics are not well understood,concern regarding chemical contaminants retained on or within them is growing.Drinking water providers are increasingly asked about these risks,but strategies for evaluating them and the extent of treatment needed to manage them are currently lacking.Microplastics can potentially induce health effects if the concentration of contaminants adsorbed to them exceeds predetermined drinking water guidelines(e.g.,Maximum Contaminant Levels).The risk posed by microplastics due to adsorbed contaminants is difficult to determine,but a worst-case scenario can be evaluated by using adsorption capacity.Here,a“Threshold Microplastics Concentration”(TMC)framework is developed to evaluate whether waterborne microplastic concentrations can potentially result in the intake of regulated contaminants on/in microplastics at levels of human health concern and identify treatment targets for managing associated health risk.Exceeding the TMC does not indicate an immediate health risk;it informs the need for detailed risk assessment or further treatment evaluation to ensure particle removal targets are achieved.Thus,the TMC concept and framework provide an updateable,science-based screening tool to determine if there is a need for detailed risk assessment or treatment modification due to waterborne microplastics in supplies used for potable water production. 展开更多
关键词 drinking water treatment chemical contaminants adsorption capacity risk management maximum contaminant level
原文传递
Trace heavy metals and harmful elements in roots and rhizomes of herbs:Screening level analysis and health risk assessment 被引量:1
6
作者 Xiaoli Wu Peiling Wu +1 位作者 Mengying Gu Jian Xue 《Chinese Herbal Medicines》 CAS 2022年第4期622-629,共8页
Objective:Heavy metal and harmful element contamination are frequently reported in Chinese herbal medicines(CHMs),and roots and rhizomes parts showed a higher content than other parts.To investigate the residue level ... Objective:Heavy metal and harmful element contamination are frequently reported in Chinese herbal medicines(CHMs),and roots and rhizomes parts showed a higher content than other parts.To investigate the residue level and assess the potential human health risk of heavy metals and harmful elements in roots and rhizomes,720 batches of the sample representing 20 species of herbs from different sources were collected.Methods:The content of Pb,Cd,As,Hg,and Cu in the digests was determined using ICP-MS.The chronic hazard index estimate based on non-cancer hazard quotient(HQ)was applied for potential health risk assessment of Pb,Cd,As,Hg,and Cu via consumption of CHMs.Results:Compared with the Chinese limit standard(Chinese Pharmacopoeia Commission,2020 edition)of Pb,Cd,As,Hg,and Cu in Ginseng Radix et Rhizoma,the exceedance percentage of Pb in total samples was 14.1%,which were generally far higher than Cd,As,Hg,and Cu.Health risk assessment results based on hazard quotient calculating showed that total HQ of Cu,Pb,As,Cd,and Hg in Pulsatillae Radix and Clematidis Radix et Rhizoma exceeded 1,with the value of 1.543 and 1.235.Besides,Arsenic had the highest HQ value(0.957)in Pulsatillae Radix.Conclusion:Consuming raw materials of Pulsatillae Radix and Clematidis Radix et Rhizoma may pose a potential risk and Arsenic residues in Pulsatillae Radix deserved special attention. 展开更多
关键词 contamination level harmful element heavy metal potential risk assessment roots and rhizomes of herbs
原文传递
Risk Assessment of Metal Contamination in Soil and Groundwater in Asia: A Review of Recent Trends as well as Existing Environmental Laws and Regulations 被引量:2
7
作者 Tianlik TEH Nik Abdul Rahman NIK NORULAINI +2 位作者 Mohammad SHAHADAT Yoonsing WONG Abdul Kadir MOHD OMAR 《Pedosphere》 SCIE CAS CSCD 2016年第4期431-450,共20页
Asia is experiencing a more rapid economic growth compared to any other regions. The contamination of soil and groundwater with metals can mainly be attributed to human activities; therefore, risk assessments to chara... Asia is experiencing a more rapid economic growth compared to any other regions. The contamination of soil and groundwater with metals can mainly be attributed to human activities; therefore, risk assessments to characterize the nature and magnitude of risks to humans and ecological receptors from contaminants are important. Risk assessments are often iterative processes, which involve identification and filling data gap. Experimental samplings, geostatistical and multivariate statistical methods as well as multimedia risk assessment modeling are the three major methodologies used in the assessment of metal contamination in soil and groundwater.This review highlights a number of measurements for improving risk calculation methods and expounds scientific approaches that involve the identification of the major source of contamination, exposure pathways and bioavailability of metals. In general, risk assessments of metals in soil and groundwater worldwide are mainly focused on the levels of contamination, identification of exposure pathways, and prediction of the probability of contamination. To date, very limited studies have reported the development of relevant environmental laws and policies in the regulation of soil and groundwater contamination in Asia. The development, variations and limitations in the regulations of soil and groundwater contamination among developed countries may provide helpful guidance for the developing countries in Asia. 展开更多
关键词 bioavailability of metals environmental regulation exposure pathway levels of contamination source of contamination
原文传递
Impacts of n-alkane concentration on soil bacterial community structure and alkane monooxygenase genes abundance during bioremediation processes 被引量:1
8
作者 Yueqiao Liu Aizhong Ding +2 位作者 Yujiao Sun Xuefeng Xia Dayi Zhang 《Frontiers of Environmental Science & Engineering》 SCIE EI CSCD 2018年第5期155-167,共13页
Petroleum hydrocarbons,mainly consisting of n-alkanes and polycyclic aromatic hydrocarbons(PAHs),are considered as priority pollutants and biohazards in the environment,eventually affecting the ecosystem and human hea... Petroleum hydrocarbons,mainly consisting of n-alkanes and polycyclic aromatic hydrocarbons(PAHs),are considered as priority pollutants and biohazards in the environment,eventually affecting the ecosystem and human health.Though many previous studies have investigated the change of bacterial community and alkane degraders during the degradation of petroleum hydrocarbons,there is still lack of understanding on the impacts of soil alkane contamination level.In the present study,microcosms with different n-alkane contamination(1%,3%and 5%)were set up and our results indicated a complete alkane degradation after 30 and 50 days in 1%-and 3%-alkane treatments,respectively.In all the treatments,alkanes with medium-chain length(C_(11)-C_(14))were preferentially degraded by soil microbes,followed by C27-alkane in 3%and 5%treatments.Alkane contamination level slightly altered soil bacterial community,and the main change was the presence and abundance of dominant alkane degraders.Thermogemmatisporaceae,Gemmataceae and Thermodesulfovibrionaceae were highly related to the degradation of C_(14)-and C_(27)-alkanes in 5%treatment,but linked to alkanes with medium-chain(C11-C18)in 1%treatment and C21-alkane in 3%treatment,respectively.Additionally,we compared the abundance of three alkane-monooxygenase genes,e.g.,alk_A,alk_P and alk_R.The abundance of alk_R gene was highest in soils,and alk_P gene was more correlated with alkane degradation efficiency,especially in 5%treatment.Our results suggested that alkane contamination level showed non-negligible effects on soil bacterial communities to some extents,and particularly shaped alkane degraders and degrading genes significantly.This study provides a better understanding on the response of alkane degraders and bacterial communities to soil alkane concentrations,which affects their biodegradation process. 展开更多
关键词 Petroleum hydrocarbon contaminated site n-alkane contamination level n-alkane biodegradation Soil bacterial community Alkane degraders Alkane-monooxygenase genes
原文传递
上一页 1 下一页 到第
使用帮助 返回顶部