Pub Date : 2015-01-01DOI: 10.2428/ECEA.2015.22(1)07
B. Filipek-Mazur, M. Tabak
The research was conducted to determine the influence of fertilization with waste organic materials on the content and uptake of lead by maize as well as on the total content of lead in soil. The three-year field experiment comprised 7 treatments: a non-fertilized soil (control treatment) as well as a soil fertilized with mineral fertilizers, cattle manure, green waste compost, sewage sludge, compost from sewage sludge and straw as well as with a mixture of sewage sludge and hard coal ash. Maize cultivated for silage was the test plant. The lead content in the above-ground parts of plants and in the soil was determined using ICP-AES method. During the research, no lead pollution of the soil or the above-ground parts of the maize was found. No statistically significant effect of fertilization on the lead content in the maize was found or the fertilized plants contained considerably less of the element than the control plants. The lowest weighted mean content of lead was found in the maize fertilized with the green waste compost, sewage sludge as well as with the compost from sludge and straw. Soil with the lowest lead content was the soil of the treatment fertilized with organic materials. The soil fertilized with the green waste compost (all the years), sewage sludge (2 year) as well as with the mixture of sludge and ash (1 and 2 year) contained significantly more lead than the soil fertilized with mineral fertilizers.
{"title":"Content of nickel in maize and soil fertilized with organic materials derived from waste","authors":"B. Filipek-Mazur, M. Tabak","doi":"10.2428/ECEA.2015.22(1)07","DOIUrl":"https://doi.org/10.2428/ECEA.2015.22(1)07","url":null,"abstract":"The research was conducted to determine the influence of fertilization with waste organic materials on the content and uptake of lead by maize as well as on the total content of lead in soil. The three-year field experiment comprised 7 treatments: a non-fertilized soil (control treatment) as well as a soil fertilized with mineral fertilizers, cattle manure, green waste compost, sewage sludge, compost from sewage sludge and straw as well as with a mixture of sewage sludge and hard coal ash. Maize cultivated for silage was the test plant. The lead content in the above-ground parts of plants and in the soil was determined using ICP-AES method. During the research, no lead pollution of the soil or the above-ground parts of the maize was found. No statistically significant effect of fertilization on the lead content in the maize was found or the fertilized plants contained considerably less of the element than the control plants. The lowest weighted mean content of lead was found in the maize fertilized with the green waste compost, sewage sludge as well as with the compost from sludge and straw. Soil with the lowest lead content was the soil of the treatment fertilized with organic materials. The soil fertilized with the green waste compost (all the years), sewage sludge (2 year) as well as with the mixture of sludge and ash (1 and 2 year) contained significantly more lead than the soil fertilized with mineral fertilizers.","PeriodicalId":44472,"journal":{"name":"ECOLOGICAL CHEMISTRY AND ENGINEERING A-CHEMIA I INZYNIERIA EKOLOGICZNA A","volume":"24 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2015-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68904591","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2015-01-01DOI: 10.2428/ECEA.2015.22(1)10
W. Szczepaniak, M. Zabłocka-Malicka, Amelia. Zielińska, P. Rutkowski
Original, non-separated pieces of the LiYCY cable (with multilayer metal/plastic (copper/PVC) structure) were gasified by steam in an excess at atmospheric pressure. Conversion of the gaseous stream was enhanced by catalytic bed of original granulated material, prepared from aluminosilicate (local clay) and calcium carbonate. In the process metal (Cu) preserved unchanged form of cords and braids and was quantitatively separated (49 % of original mass of the cable). Non-metal components (51 % of original mass of the cable) were converted to a slightly sintered non-metallic powder (3.3 % of original mass of the cable) and gaseous phase. Condensation of steam facilitated elimination of tars and oils as well as hydrochloride from the gas. It was estimated that only 5 % of carbon (from the cable components) was retained in the cooling/condensing line, mostly as water non-soluble phases. Efficiency of absorption of hydrochloride by catalytic bed and aqueous condensate was almost the same (but only 50 % of estimated total chlorine quantity was finally balanced).
{"title":"Steam gasification of multiwire LiYCY type electrical cable","authors":"W. Szczepaniak, M. Zabłocka-Malicka, Amelia. Zielińska, P. Rutkowski","doi":"10.2428/ECEA.2015.22(1)10","DOIUrl":"https://doi.org/10.2428/ECEA.2015.22(1)10","url":null,"abstract":"Original, non-separated pieces of the LiYCY cable (with multilayer metal/plastic (copper/PVC) structure) were gasified by steam in an excess at atmospheric pressure. Conversion of the gaseous stream was enhanced by catalytic bed of original granulated material, prepared from aluminosilicate (local clay) and calcium carbonate. In the process metal (Cu) preserved unchanged form of cords and braids and was quantitatively separated (49 % of original mass of the cable). Non-metal components (51 % of original mass of the cable) were converted to a slightly sintered non-metallic powder (3.3 % of original mass of the cable) and gaseous phase. Condensation of steam facilitated elimination of tars and oils as well as hydrochloride from the gas. It was estimated that only 5 % of carbon (from the cable components) was retained in the cooling/condensing line, mostly as water non-soluble phases. Efficiency of absorption of hydrochloride by catalytic bed and aqueous condensate was almost the same (but only 50 % of estimated total chlorine quantity was finally balanced).","PeriodicalId":44472,"journal":{"name":"ECOLOGICAL CHEMISTRY AND ENGINEERING A-CHEMIA I INZYNIERIA EKOLOGICZNA A","volume":"22 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2015-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68904620","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2015-01-01DOI: 10.2428/ECEA.2015.22(2)13
J. Guziałowska-Tic, W. Tic
It is necessary to use specific modifiers in order to reduce harmful emissions arising in the combustion of liquid fuels into the atmosphere. Such modifiers include organic metal salts which are soluble in fuels and tend to form metal oxides under combustion process conditions, improving the oxidizing properties of fuels. The modifier, described in this paper was used in liquid fuel combustion tests, showing a desirable effect of reducing CO, NOx and hydrocarbon emissions. For such modifiers to be approved for use, examination of their physico-chemical, toxicological and ecotoxicological properties is required according to REACH Regulation. REACH is intended, first of all, to provide appropriate protection to the environment and human health, while striving to maintain competitiveness of European enterprises in the global market. Discussed in this paper are the results of selected tests of the effect of an iron-based modifier for liquid fuels on human health and on the land and air and the aquatic environment. The modifier was subjected to physico-chemical analyses, and toxicological and ecotoxicological tests in accordance with good laboratory practice and OECD guidelines. The test results indicate that the modifier is a safe substance, posing no hazard to human health or the environment.
{"title":"Toxicological and ecotoxicological properties of an iron based combustion modifier for liquid fuels","authors":"J. Guziałowska-Tic, W. Tic","doi":"10.2428/ECEA.2015.22(2)13","DOIUrl":"https://doi.org/10.2428/ECEA.2015.22(2)13","url":null,"abstract":"It is necessary to use specific modifiers in order to reduce harmful emissions arising in the combustion of liquid fuels into the atmosphere. Such modifiers include organic metal salts which are soluble in fuels and tend to form metal oxides under combustion process conditions, improving the oxidizing properties of fuels. The modifier, described in this paper was used in liquid fuel combustion tests, showing a desirable effect of reducing CO, NOx and hydrocarbon emissions. For such modifiers to be approved for use, examination of their physico-chemical, toxicological and ecotoxicological properties is required according to REACH Regulation. REACH is intended, first of all, to provide appropriate protection to the environment and human health, while striving to maintain competitiveness of European enterprises in the global market. Discussed in this paper are the results of selected tests of the effect of an iron-based modifier for liquid fuels on human health and on the land and air and the aquatic environment. The modifier was subjected to physico-chemical analyses, and toxicological and ecotoxicological tests in accordance with good laboratory practice and OECD guidelines. The test results indicate that the modifier is a safe substance, posing no hazard to human health or the environment.","PeriodicalId":44472,"journal":{"name":"ECOLOGICAL CHEMISTRY AND ENGINEERING A-CHEMIA I INZYNIERIA EKOLOGICZNA A","volume":"22 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2015-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68904666","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2015-01-01DOI: 10.2428/ecea.2015.22(3)33
A. Hałat, R. Kędzior, D. Grzesiak, J. Głowiński
Stability of the polypropylene composite with fiber glass (45/55) in the form of low density mat was tested experimentally at increased temperature. It was examined by analyzing the influence of the atmosphere with various oxygen content on the decomposition rate of the polypropylene composite. It has been found that in the air atmosphere, the initial decomposition temperature is close to 200 C. Lowering the oxygen concentration in the atmosphere to 2 % results in increase of composite decomposition temperature to almost 240 C. Decomposition components were identified in the methylene chloride extract from composite and in the condensed reaction products. Rate of decomposition conversion at initial stage below 0.2 was estimated as a system of equations: zero order path r = k1 for polypropylene degradation and first order path r = k2[O2] for oxidative decomposition. A brief safety analysis is performed identifying the possibility of exceeding an explosion limit under certain conditions. The best way of mitigating the fire/explosion hazard is lowering the oxygen content below 2 % vol., especially for processing of recycled polypropylene.
{"title":"Thermal stability of polypropylene composite reinforced with glass fibre in the oxidising atmosphere","authors":"A. Hałat, R. Kędzior, D. Grzesiak, J. Głowiński","doi":"10.2428/ecea.2015.22(3)33","DOIUrl":"https://doi.org/10.2428/ecea.2015.22(3)33","url":null,"abstract":"Stability of the polypropylene composite with fiber glass (45/55) in the form of low density mat was tested experimentally at increased temperature. It was examined by analyzing the influence of the atmosphere with various oxygen content on the decomposition rate of the polypropylene composite. It has been found that in the air atmosphere, the initial decomposition temperature is close to 200 C. Lowering the oxygen concentration in the atmosphere to 2 % results in increase of composite decomposition temperature to almost 240 C. Decomposition components were identified in the methylene chloride extract from composite and in the condensed reaction products. Rate of decomposition conversion at initial stage below 0.2 was estimated as a system of equations: zero order path r = k1 for polypropylene degradation and first order path r = k2[O2] for oxidative decomposition. A brief safety analysis is performed identifying the possibility of exceeding an explosion limit under certain conditions. The best way of mitigating the fire/explosion hazard is lowering the oxygen content below 2 % vol., especially for processing of recycled polypropylene.","PeriodicalId":44472,"journal":{"name":"ECOLOGICAL CHEMISTRY AND ENGINEERING A-CHEMIA I INZYNIERIA EKOLOGICZNA A","volume":"19 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2015-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68905300","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2015-01-01DOI: 10.2428/ECEA.2015.22(1)04
J. Mucha
{"title":"Characteristics of grey water filtration on polypropylene filters","authors":"J. Mucha","doi":"10.2428/ECEA.2015.22(1)04","DOIUrl":"https://doi.org/10.2428/ECEA.2015.22(1)04","url":null,"abstract":"","PeriodicalId":44472,"journal":{"name":"ECOLOGICAL CHEMISTRY AND ENGINEERING A-CHEMIA I INZYNIERIA EKOLOGICZNA A","volume":"22 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2015-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68905049","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2015-01-01DOI: 10.2428/ECEA.2015.22(1)05
A. Dereszewska, A. Tuszyńska, S. Cytawa
The work concerns the evaluation of the possibility of using laser diffraction analyzer to determine changes in the distribution of sludge floc size in the presence of anionic surfactant. As a model of surfactant linear alkylbenzene sulphonate (LAS) was used. Different concentrations: 10, 100 and 200 mg/dm of LAS was applied. The granulometric analysis showed that the pure activated sludge was composed of particles with a size of 1 m to 2 mm. The largest and fastest changes in the distribution of sludge floc size after the addition of a surfactant at a concentration of 100 mg/dm were observed. The flocs with a diameter above 0.8 mm disappear and the average diameter over volume of particles decrease from 0.29 to 0.19 mm. Doubling the dose of surfactant causes the flocs aggregation. The sludge flocs capability for break-up and aggregation is not proportional to the concentration of LAS. Addition of LAS to the sludge results in decrease of the sludge volume index. This study showed that granulometric measurement may help to estimate an impact of chemical substances contained in wastewater on activated sludge.
{"title":"Granulometric analysis to estimate influence of anionic surfactant on activated sludge structure","authors":"A. Dereszewska, A. Tuszyńska, S. Cytawa","doi":"10.2428/ECEA.2015.22(1)05","DOIUrl":"https://doi.org/10.2428/ECEA.2015.22(1)05","url":null,"abstract":"The work concerns the evaluation of the possibility of using laser diffraction analyzer to determine changes in the distribution of sludge floc size in the presence of anionic surfactant. As a model of surfactant linear alkylbenzene sulphonate (LAS) was used. Different concentrations: 10, 100 and 200 mg/dm of LAS was applied. The granulometric analysis showed that the pure activated sludge was composed of particles with a size of 1 m to 2 mm. The largest and fastest changes in the distribution of sludge floc size after the addition of a surfactant at a concentration of 100 mg/dm were observed. The flocs with a diameter above 0.8 mm disappear and the average diameter over volume of particles decrease from 0.29 to 0.19 mm. Doubling the dose of surfactant causes the flocs aggregation. The sludge flocs capability for break-up and aggregation is not proportional to the concentration of LAS. Addition of LAS to the sludge results in decrease of the sludge volume index. This study showed that granulometric measurement may help to estimate an impact of chemical substances contained in wastewater on activated sludge.","PeriodicalId":44472,"journal":{"name":"ECOLOGICAL CHEMISTRY AND ENGINEERING A-CHEMIA I INZYNIERIA EKOLOGICZNA A","volume":"22 1","pages":"51-56"},"PeriodicalIF":0.0,"publicationDate":"2015-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68905057","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2015-01-01DOI: 10.2428/ECEA.2015.22(3)26
J. Matuska-Łyżwa
{"title":"Invasiveness and reproduction of the Steinernema feltiae from selected agrocoenose located in Wielun","authors":"J. Matuska-Łyżwa","doi":"10.2428/ECEA.2015.22(3)26","DOIUrl":"https://doi.org/10.2428/ECEA.2015.22(3)26","url":null,"abstract":"","PeriodicalId":44472,"journal":{"name":"ECOLOGICAL CHEMISTRY AND ENGINEERING A-CHEMIA I INZYNIERIA EKOLOGICZNA A","volume":"22 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2015-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68905108","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2015-01-01DOI: 10.2428/ECEA.2015.22(3)29
D. Świerk, M. Krzyżaniak, Miłosz T. Walerzak, P. Urbański
{"title":"Assessment of the effect of environmental variables on health status of Tilia cordata Mill. in parks","authors":"D. Świerk, M. Krzyżaniak, Miłosz T. Walerzak, P. Urbański","doi":"10.2428/ECEA.2015.22(3)29","DOIUrl":"https://doi.org/10.2428/ECEA.2015.22(3)29","url":null,"abstract":"","PeriodicalId":44472,"journal":{"name":"ECOLOGICAL CHEMISTRY AND ENGINEERING A-CHEMIA I INZYNIERIA EKOLOGICZNA A","volume":"22 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2015-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68905160","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2015-01-01DOI: 10.2428/ECEA.2015.22(3)24
K. Jaromin-Gleń, E. Kurek, M. Bis, A. Kopertowska, M. Jaczyński, M. Jaworska
The study presents the effect of modernization of selected elements of the technological line in the ‘Hajdów’ municipal wastewater treatment plant (WWTP) on the course of the process of wastewater treatment. The researchers paid special attention to the changes in the amount of emerging waste (rake bar screens, sand, excess sludge) due to modernization, and the elimination of odour nuisance from the plant. Technological changes in the system of activated sludge bioreactor contributed to a considerable increase in the amount of excess sludge. This caused problems with its effective management with the use of previously applied methods and devices; therefore, facilities were introduced supporting the dehydration of excess sludge. Therefore, the article also presents the description of solutions concerning the processing of sludge introduced to-date in the ‘Hajdów’ WWTP and further modernizations implemented.
{"title":"Effect of “Hajdow” wastewater treatment plant modernization on wastewater purification process","authors":"K. Jaromin-Gleń, E. Kurek, M. Bis, A. Kopertowska, M. Jaczyński, M. Jaworska","doi":"10.2428/ECEA.2015.22(3)24","DOIUrl":"https://doi.org/10.2428/ECEA.2015.22(3)24","url":null,"abstract":"The study presents the effect of modernization of selected elements of the technological line in the ‘Hajdów’ municipal wastewater treatment plant (WWTP) on the course of the process of wastewater treatment. The researchers paid special attention to the changes in the amount of emerging waste (rake bar screens, sand, excess sludge) due to modernization, and the elimination of odour nuisance from the plant. Technological changes in the system of activated sludge bioreactor contributed to a considerable increase in the amount of excess sludge. This caused problems with its effective management with the use of previously applied methods and devices; therefore, facilities were introduced supporting the dehydration of excess sludge. Therefore, the article also presents the description of solutions concerning the processing of sludge introduced to-date in the ‘Hajdów’ WWTP and further modernizations implemented.","PeriodicalId":44472,"journal":{"name":"ECOLOGICAL CHEMISTRY AND ENGINEERING A-CHEMIA I INZYNIERIA EKOLOGICZNA A","volume":"22 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2015-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68905561","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2015-01-01DOI: 10.2428/ECEA.2015.22(2)14
K. Wolny-Koładka, M. Malinowski
The subject of the study is the analysis of the number of microorganisms forming a microbiological aerosol in a municipal solid waste treatment plant in Krakow. The storage time of mixed municipal solid waste in the plant hall is 6–48 hours and the storage time of the produced alternative fuel is within the range of 12–96 hours. 18 employees work in the three shift system in the sorting facility. The air for research was sampled using a MAS-100 impactor (Merck, Switzerland) in three locations within the plant, four times within a year to assess the effect of meteorological conditions (temperature, humidity and dustiness) on the number of selected groups of microorganisms. It was found that the number of microorganisms changes with seasons and depends on the meteorological conditions as well as the air sampling location. Since the border values of bioaerosol concentration were exceeded, further research is required to assess the changes in the number of microorganisms with potential negative impact on human health.
{"title":"Assessment of the microbiological contamination of air in a municipal solid waste treatment company","authors":"K. Wolny-Koładka, M. Malinowski","doi":"10.2428/ECEA.2015.22(2)14","DOIUrl":"https://doi.org/10.2428/ECEA.2015.22(2)14","url":null,"abstract":"The subject of the study is the analysis of the number of microorganisms forming a microbiological aerosol in a municipal solid waste treatment plant in Krakow. The storage time of mixed municipal solid waste in the plant hall is 6–48 hours and the storage time of the produced alternative fuel is within the range of 12–96 hours. 18 employees work in the three shift system in the sorting facility. The air for research was sampled using a MAS-100 impactor (Merck, Switzerland) in three locations within the plant, four times within a year to assess the effect of meteorological conditions (temperature, humidity and dustiness) on the number of selected groups of microorganisms. It was found that the number of microorganisms changes with seasons and depends on the meteorological conditions as well as the air sampling location. Since the border values of bioaerosol concentration were exceeded, further research is required to assess the changes in the number of microorganisms with potential negative impact on human health.","PeriodicalId":44472,"journal":{"name":"ECOLOGICAL CHEMISTRY AND ENGINEERING A-CHEMIA I INZYNIERIA EKOLOGICZNA A","volume":"22 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2015-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68904675","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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