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1.
Appl Opt ; 60(13): 4034-4038, 2021 May 01.
Article in English | MEDLINE | ID: mdl-33983344

ABSTRACT

According to the high-voltage and small-current characteristics for unbalanced current of high-voltage capacitors, a novel fiber optical filter unbalanced current transformer (FU-FOCT) is proposed, where an all-fiber temperature sensor based on the temperature birefringence effect of polarization-maintaining fiber is designed and integrated into an FU-FOCT for real-time temperature correction. The FU-FOCT prototype with a rated current of 1 A and a rated voltage of 258 kV is developed, and the accuracy, temperature, and frequency-response characteristics are tested. The results show that within the temperature range of ${-}{40}^\circ {\rm C} - 70^\circ {\rm C}$, the fluctuation range of the ratio error and phase error of the FU-FOCT at 1 A are ${-}{0.042}\% - 0.08\%$ and ${-}{0.16^\prime - 0.18^\prime}$, respectively, which meet the error limit requirements of class 0.2% specified in GB/T 20840.8-2007.

2.
J Environ Manage ; 223: 841-848, 2018 Oct 01.
Article in English | MEDLINE | ID: mdl-29986332

ABSTRACT

Sustainable consumption and production are considered to be fundamental ways to solve problems with environmental resources that human beings are facing. There is a broad consensus that promoting sustainable consumption requires the joint efforts of different social actors. This paper aims to define the roles of different stakeholders and the relationships between them, and then establish a modeling framework to analyze those relationships between stakeholders, which include members of government, business, consumer, mass media, environmental non-government organizations, education and research institutions, financial markets, etc. The research found that members of government, business, and consumers make up the core stakeholder network. The modeling framework could be used to evaluate sustainable consumption practices and identify deficiencies that would assist in defining better trajectories. This paper describes the evaluation of sustainable consumption practice in Tianjin, China from a stakeholder perspective to show how the modeling framework can function. According to this analysis, the following six actions may promote sustainable consumption practices in areas like Tianjin: 1) the cultivation of a consciousness of sustainable consumption, 2) the exemplary role of government, 3) a series of laws, regulations, and policies, 4) a thorough sustainable consumption action plan, 5) an insistence on sustainable production and consumption by businesses and consumers, and 6) the concerted efforts of various stakeholders.


Subject(s)
Conservation of Natural Resources , Stakeholder Participation , China , Government , Humans , Organizations
3.
Article in English | MEDLINE | ID: mdl-28767096

ABSTRACT

A 'red line' was established, identifying an area requiring for ecological protection in Tianjin, China. Within the protected area of the red line area, the Qilihai wetland is an important ecotope with complex ecological functions, although the ecosystem is seriously disturbed due to anthropogenic activities in the surrounding areas. This study assesses the water quality status of the Qilihai wetlands to identify the pollution sources and potential improvements based on the ecological red line policy, to improve and protect the waters of the Qilihai wetlands. An indicator system was established to assess water quality status using single factor evaluation and a comprehensive evaluation method, supported by data from 2010 to 2013. Assessment results show that not all indicators met the requirement of the Environmental Quality Standards for Surface Water (GB3838-2002) and that overall, waters in the Qilihai wetland were seriously polluted. Based on these findings we propose restrictions on all polluting anthropogenic activities in the red line area and implementation of restoration projects to improve water quality.


Subject(s)
Conservation of Natural Resources , Water Quality , Wetlands , China , Ecosystem , Environmental Monitoring , Water Pollution/analysis
4.
Sci Total Environ ; 599-600: 721-731, 2017 Dec 01.
Article in English | MEDLINE | ID: mdl-28499221

ABSTRACT

Severe water pollution and resource scarcity is a major problem in China, where it is necessary to establish water quality-oriented monitoring and intelligent watershed management. In this study, an effective watershed management method is explored, in which water quality is first assessed using the heavy metal pollution index and the human health risk index, and then by classifying the pollution and management grade based on cluster analysis and GIS visualization. Three marine reserves in Tianjin were selected and analyzed, namely the Tianjin Ancient Coastal Wetland National Nature Reserve (Qilihai Natural Reserve), the Tianjin DaShentang Oyster Reef National Marine Special Reserve (DaShentang Reserve), and the Tianjin Coastal Wetland National Marine Special Reserve (BinHai Wetland Reserve) which is under construction. The water quality and potential human health risks of 5 heavy metals (Pb, As, Cd, Hg, Cr) in the three reserves were assessed using the Nemerow index and USEPA methods. Moreover, ArcGIS10.2 software was used to visualize the heavy metal index and display their spatial distribution. Cluster analysis enabled classification of the heavy metals into 4 categories, which allowed for identification of the heavy metals whose pollution index and health risks were highest, and, thus, whose control in the reserve is a priority. Results indicate that heavy metal pollution exists in the Qilihai Natural Reserve and in the north and east of the DaShentang Reserve; furthermore, human health risks exist in the Qilihai Natural Reserve and in the BinHai Wetland Reserve. In each reserve, the main factor influencing the pollution and health risk were high concentrations of As and Pb that exceed the corresponding standards. Measures must be adopted to control and remediate the pollutants. Furthermore, to protect the marine reserves, management policies must be implemented to improve water quality, which is an urgent task for both local and national governments.


Subject(s)
Environmental Monitoring , Metals, Heavy/analysis , Water Pollutants, Chemical/analysis , Water Quality , China , Conservation of Natural Resources , Humans , Risk Assessment , Water , Wetlands
5.
Article in Chinese | MEDLINE | ID: mdl-25345147

ABSTRACT

OBJECTIVE: To understand the characteristics of schistosome cercarial infested water contact of residents in Poyang Lake endemic areas after the operation of Three Gorges Project, so as to provide the evidence for formulating a well-directed control strategy. METHODS: The residents in two villages in schistosomiasis endemic areas were selected and surveyed for their activities of infested water contacts by questionnaire. RESULTS: The proportion and frequency of infested water contacts of residents in Poyang Lake region were high and the average rate of infested water contacts was 69.77%, and 98.96% of infested water contacts occurred in spring, summer and autumn. The main ways of infested water contacts were fishing/swimming/playing for adult men, washing clothes/fishing for adult women, and swimming/playing for school children, respectively. The rates of infested water contacts were 73.33%, 71.63% and 61.87% in adult men, women and school children, respectively. The frequencies of infested water contacts > 1 time/week, 1 time/week-1 time/month, and < 1 time/month were 62.61%, 23.74% and 13.66% respectively. CONCLUSIONS: The infested water contacts mainly occurs in spring, summer and autumn, and the main way of infested water contacts was fishing. Farming and mowing grass, which had been the primary way, now become the secondary way for the adult residents.


Subject(s)
Engineering , Lakes/parasitology , Schistosoma/physiology , Schistosomiasis/epidemiology , Water/parasitology , Adolescent , Adult , Age Distribution , Animals , Child , Child, Preschool , China/epidemiology , Female , Humans , Male , Middle Aged , Occupations/statistics & numerical data , Schistosomiasis/transmission , Seasons , Sex Distribution , Young Adult
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