Pub Date : 2018-12-22DOI: 10.25135/JCM.20.18.11.1076
M. S. Dundar, H. Altundağ, Gülşah Tunca
Boron is an essential nutrient for plants and an essential element for many organisms, but can be toxic to aquatic and terrestrial organisms above certain concentrations. The aim of this research is determining the Boron content of four varieties of Hazelnut (Corylus avellana L.) from Sakarya. Inductively coupled plasma optical emission spectrometry (ICP-OES) with ultrasonic nebulization (USN) was used for the determination of Boron contents. This method is based on microwave digestion system and reduced memory effect of Boron by using sorbitol. Different conditions were optimized for this method. Four hazelnut varieties, eight soil samples and certificated reference material (NIM-GBW10012) were analyzed. The Boron contents were found as 18.27, 28.3, 38.6, 17.6 mg/kg in Kara, Sivri, Delisava and Tombul hazelnut varieties, respectively. And Boron contents of soil samples were between 30.44 to 196.79 mg/kg. The results revealed that the Turkish hazelnut is a good natural source of Boron.
{"title":"Determination of Boron in hazelnut varieties with the addition of sorbitol by using ICP-OES and ultrasonic nebulization after microwave digestion system","authors":"M. S. Dundar, H. Altundağ, Gülşah Tunca","doi":"10.25135/JCM.20.18.11.1076","DOIUrl":"https://doi.org/10.25135/JCM.20.18.11.1076","url":null,"abstract":"Boron is an essential nutrient for plants and an essential element for many organisms, but can be toxic to aquatic and terrestrial organisms above certain concentrations. The aim of this research is determining the Boron content of four varieties of Hazelnut (Corylus avellana L.) from Sakarya. Inductively coupled plasma optical emission spectrometry (ICP-OES) with ultrasonic nebulization (USN) was used for the determination of Boron contents. This method is based on microwave digestion system and reduced memory effect of Boron by using sorbitol. Different conditions were optimized for this method. Four hazelnut varieties, eight soil samples and certificated reference material (NIM-GBW10012) were analyzed. The Boron contents were found as 18.27, 28.3, 38.6, 17.6 mg/kg in Kara, Sivri, Delisava and Tombul hazelnut varieties, respectively. And Boron contents of soil samples were between 30.44 to 196.79 mg/kg. The results revealed that the Turkish hazelnut is a good natural source of Boron.","PeriodicalId":15343,"journal":{"name":"Journal of Chemical Metrology","volume":null,"pages":null},"PeriodicalIF":1.3,"publicationDate":"2018-12-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47935458","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 : 2018-12-22DOI: 10.25135/jcm.18.18.09.950
F. Rezai, S. Isik, M. Kartal, S. Erdem
The aim of this study is to analyze the changes on thymoquinone content, which is the major constituent of black cumin (Nigella sativa L.) seeds, by using priming methods. For the priming studies, seeds placed in distilled water (18 20 hours), PEG (Polyethylene glycol 10%, 20%) and mannitol (4% and 6%) for 20 hours and subsequently dried for 24 hours on blotting paper at room temperature (24 C ± 1 C). The best priming results were obtained in the 4% of mannitol treatment. Control (not primed) Nigella seeds and 4% of mannitol primed seeds were planted in both greenhouse and farm conditions. Seed extracts were analyzed with HPLC to compare the amount of thymoquinone. The results reveal that seed priming with 4% of mannitol increases the amount of thymoquinone in Nigella sativa. In addition, the effects of plant growth hormones on callus regeneration of these primed seeds were investigated herein.
{"title":"Effect of priming on thymoquinone content and in vitro plant regeneration with tissue culture of black cumin (Nigella sativa L.) seeds","authors":"F. Rezai, S. Isik, M. Kartal, S. Erdem","doi":"10.25135/jcm.18.18.09.950","DOIUrl":"https://doi.org/10.25135/jcm.18.18.09.950","url":null,"abstract":"The aim of this study is to analyze the changes on thymoquinone content, which is the major constituent of black cumin (Nigella sativa L.) seeds, by using priming methods. For the priming studies, seeds placed in distilled water (18 20 hours), PEG (Polyethylene glycol 10%, 20%) and mannitol (4% and 6%) for 20 hours and subsequently dried for 24 hours on blotting paper at room temperature (24 C ± 1 C). The best priming results were obtained in the 4% of mannitol treatment. Control (not primed) Nigella seeds and 4% of mannitol primed seeds were planted in both greenhouse and farm conditions. Seed extracts were analyzed with HPLC to compare the amount of thymoquinone. The results reveal that seed priming with 4% of mannitol increases the amount of thymoquinone in Nigella sativa. In addition, the effects of plant growth hormones on callus regeneration of these primed seeds were investigated herein.","PeriodicalId":15343,"journal":{"name":"Journal of Chemical Metrology","volume":null,"pages":null},"PeriodicalIF":1.3,"publicationDate":"2018-12-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43909964","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 : 2018-12-22DOI: 10.25135/jcm.22.18.11.1073
M. S. Dundar, H. Altundağ
{"title":"Distribution of some major and trace elements in the lower Sakarya River by using ICP-MS","authors":"M. S. Dundar, H. Altundağ","doi":"10.25135/jcm.22.18.11.1073","DOIUrl":"https://doi.org/10.25135/jcm.22.18.11.1073","url":null,"abstract":"","PeriodicalId":15343,"journal":{"name":"Journal of Chemical Metrology","volume":null,"pages":null},"PeriodicalIF":1.3,"publicationDate":"2018-12-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49399625","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 : 2018-12-22DOI: 10.25135/JCM.21.18.11.1115
S. Carikci, T. Kilic, Züleyha Özer, T. Dirmenci, T. Arabaci, A. Gören
In this study, quantities of some phenolics; caffeic acid, (E)-ferulic acid, rosmarinic acid, chlorogenic acid, fumaric acid, gallic acid, pyrogallol and vanillin in the directly methanol (M1), chloroform (C), acetone (Ac) and methanol (M2) extratcs obtained from Origanum laevigatum Boiss. from Turkey were investigated via liquid chromatography and tandem mass spectrometry (LC-MS/MS). Curcumin was used as an internal standard. Caffeic acid, chlorogenic acid, rosmarinic acid and gallic acid were determined as the most abundant phenolic acids in the studied extracts using LC-MS/MS. In LC-MS/MS measurements relative standard deviations (RSD %) for caffeic acid, (E)-ferulic acid, rosmarinic acid, chlorogenic acid, fumaric acid, gallic acid, pyrogallol and vanillin were found to be 8.04, 5.21, 5.45, 3.73, 5.44, 4.85, 5.47 and 6.57 % respectively. For the investigated analytes, the correlation coefficient was found in the range of 0.9803 to 0.9981. Furthermore, antioxidant properties of the extracts were determined based on 2,2-diphenyl-1picrylhydrazyl (DPPH), β-carotene linoleic acid and cupric (Cu2) ion reducing power assay (CUPRAC). Acetone (Ac) and methanol (M2) extracts showed high activity in all test assays due to their high concentration of rosmarinic acid, caffeic acid and gallic acid in the extracts.
{"title":"Quantitative determination of some phenolics in Origanum laevigatum Boiss. extracts via validated LC-MS/MS metod and antioxidant activity","authors":"S. Carikci, T. Kilic, Züleyha Özer, T. Dirmenci, T. Arabaci, A. Gören","doi":"10.25135/JCM.21.18.11.1115","DOIUrl":"https://doi.org/10.25135/JCM.21.18.11.1115","url":null,"abstract":"In this study, quantities of some phenolics; caffeic acid, (E)-ferulic acid, rosmarinic acid, chlorogenic acid, fumaric acid, gallic acid, pyrogallol and vanillin in the directly methanol (M1), chloroform (C), acetone (Ac) and methanol (M2) extratcs obtained from Origanum laevigatum Boiss. from Turkey were investigated via liquid chromatography and tandem mass spectrometry (LC-MS/MS). Curcumin was used as an internal standard. Caffeic acid, chlorogenic acid, rosmarinic acid and gallic acid were determined as the most abundant phenolic acids in the studied extracts using LC-MS/MS. In LC-MS/MS measurements relative standard deviations (RSD %) for caffeic acid, (E)-ferulic acid, rosmarinic acid, chlorogenic acid, fumaric acid, gallic acid, pyrogallol and vanillin were found to be 8.04, 5.21, 5.45, 3.73, 5.44, 4.85, 5.47 and 6.57 % respectively. For the investigated analytes, the correlation coefficient was found in the range of 0.9803 to 0.9981. Furthermore, antioxidant properties of the extracts were determined based on 2,2-diphenyl-1picrylhydrazyl (DPPH), β-carotene linoleic acid and cupric (Cu2) ion reducing power assay (CUPRAC). Acetone (Ac) and methanol (M2) extracts showed high activity in all test assays due to their high concentration of rosmarinic acid, caffeic acid and gallic acid in the extracts.","PeriodicalId":15343,"journal":{"name":"Journal of Chemical Metrology","volume":null,"pages":null},"PeriodicalIF":1.3,"publicationDate":"2018-12-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47631175","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}
N. Nhlapo, D. Prevoo-Franzsen, Maria Fernades Whaley
{"title":"Validation of ultrasonic extraction method for the quantification of phthalates in poly (vinyl chloride) and polypropylene matrices at low concentrations by gas-chromatography time of flight mass spectrometry (GC-TOFMS)","authors":"N. Nhlapo, D. Prevoo-Franzsen, Maria Fernades Whaley","doi":"10.25135/JCM.18.12.1094","DOIUrl":"https://doi.org/10.25135/JCM.18.12.1094","url":null,"abstract":"","PeriodicalId":15343,"journal":{"name":"Journal of Chemical Metrology","volume":null,"pages":null},"PeriodicalIF":1.3,"publicationDate":"2018-12-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45047071","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 : 2018-06-06DOI: 10.25135/JCM.11.17.12.060
R. Kaarls
Reliable, correct results of chemical measurements and analysis, with a measurement uncertainty statement fit for its purpose, are highly important for drawing the right conclusions and making the right decisions. Addressing the complex parameters influencing climate change, the consequences of unsafe food, the costly clinical diagnostics and the health effects of expensive pharmaceuticals, as well as addressing the need for new sustainable energy sources and fair trade, require accurate measurements. In 1993, by decision of the International Committee for Weights and Measures (CIPM), being the directive and supervisory body under the intergovernmental treaty, known as the “Metre Convention” and signed in 1875 with the aim of establishing and maintaining a global measurement system, the scientific Consultative Committee for Metrology in Chemistry and Biology (CCQM) was created. The CCQM is charged to establish global comparability of chemical and biological measurements and analysis through metrological traceability to the International System of Units, the SI, and very well defined pure reference materials and (primary) measurement methods and procedures. The article describes in short in which context the CCQM started and developed, how it is currently organized, what it has achieved and which priorities are being set in addressing the most important chemical and biological measurement issues in the near and medium term future.
{"title":"The Consultative Committee for Metrology in Chemistry and Biology – CCQM","authors":"R. Kaarls","doi":"10.25135/JCM.11.17.12.060","DOIUrl":"https://doi.org/10.25135/JCM.11.17.12.060","url":null,"abstract":"Reliable, correct results of chemical measurements and analysis, with a measurement uncertainty statement fit for its purpose, are highly important for drawing the right conclusions and making the right decisions. Addressing the complex parameters influencing climate change, the consequences of unsafe food, the costly clinical diagnostics and the health effects of expensive pharmaceuticals, as well as addressing the need for new sustainable energy sources and fair trade, require accurate measurements. In 1993, by decision of the International Committee for Weights and Measures (CIPM), being the directive and supervisory body under the intergovernmental treaty, known as the “Metre Convention” and signed in 1875 with the aim of establishing and maintaining a global measurement system, the scientific Consultative Committee for Metrology in Chemistry and Biology (CCQM) was created. The CCQM is charged to establish global comparability of chemical and biological measurements and analysis through metrological traceability to the International System of Units, the SI, and very well defined pure reference materials and (primary) measurement methods and procedures. The article describes in short in which context the CCQM started and developed, how it is currently organized, what it has achieved and which priorities are being set in addressing the most important chemical and biological measurement issues in the near and medium term future.","PeriodicalId":15343,"journal":{"name":"Journal of Chemical Metrology","volume":null,"pages":null},"PeriodicalIF":1.3,"publicationDate":"2018-06-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42515532","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 : 2018-06-06DOI: 10.25135/JCM.12.18.01.061
Nabawia A. r Abdel-Zahe, Manal T. H. Moselhey, O. W. Guirguis
The aim of the present work was to evaluate the effect of artificial day light for 160 h on silk fabrics dyeing with different conditions such as; different dye bath pH values, different dyeing temperatures, and different dyeing times; of extracted natural dye from Azadirachta indica (neem) leaves. The reflectance spectra of the untreated and treated silk fabrics were followed using spectrophotometer technique. The effects of dyeing conditions in the optical parameters, such as; CIE tristimulus values, color parameters, absorption coefficient as well as extinction coefficient and color strength, were determined before and after exposure. The obtained results indicate that the silk fabrics were found to be highly dependent on either of these different dyeing conditions and/or artificial day light exposure. Also, variations in the values of the optical band gap energy were detected. Improvement in the dyeing process were produced which may be attributed to the induced structural change due to the variation in the chemical bonds in silk fabrics. The present work gives the chance to produce a new traditional natural dye to meet the environmental future demands technology of high quality fantastic dyed pattern.
{"title":"Study the effect of different dyeing conditions of extracted natural dye from leaves of neem on silk fabrics","authors":"Nabawia A. r Abdel-Zahe, Manal T. H. Moselhey, O. W. Guirguis","doi":"10.25135/JCM.12.18.01.061","DOIUrl":"https://doi.org/10.25135/JCM.12.18.01.061","url":null,"abstract":"The aim of the present work was to evaluate the effect of artificial day light for 160 h on silk fabrics dyeing with different conditions such as; different dye bath pH values, different dyeing temperatures, and different dyeing times; of extracted natural dye from Azadirachta indica (neem) leaves. The reflectance spectra of the untreated and treated silk fabrics were followed using spectrophotometer technique. The effects of dyeing conditions in the optical parameters, such as; CIE tristimulus values, color parameters, absorption coefficient as well as extinction coefficient and color strength, were determined before and after exposure. The obtained results indicate that the silk fabrics were found to be highly dependent on either of these different dyeing conditions and/or artificial day light exposure. Also, variations in the values of the optical band gap energy were detected. Improvement in the dyeing process were produced which may be attributed to the induced structural change due to the variation in the chemical bonds in silk fabrics. The present work gives the chance to produce a new traditional natural dye to meet the environmental future demands technology of high quality fantastic dyed pattern.","PeriodicalId":15343,"journal":{"name":"Journal of Chemical Metrology","volume":null,"pages":null},"PeriodicalIF":1.3,"publicationDate":"2018-06-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42522136","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 : 2018-06-06DOI: 10.25135/JCM.14.18.02.063
S. Charapitsa, S. Sytova, Anton Korban, Nicolai Boyarin, I. Shestakovich, R. Čabala
An extensive study concerning the problem of volatile compounds determination in alcoholic products by gas chromatography has been undertaken in the paper. A row of gravimetrically prepared standard solutions was analysed with three analytical methods: traditional method of internal standard, advanced method of internal standard and external standard method. The main analytical characteristics and metrological parameters of the “Ethanol as Internal Standard” method were compared with the traditional approaches. It was shown that this method leads to correct values of volatiles concentrations and the corresponding metrological characteristics are generally better.
{"title":"The establishment of metrological characteristics of the method “Ethanol as Internal Standard” for the direct determination of volatile compounds in alcoholic products","authors":"S. Charapitsa, S. Sytova, Anton Korban, Nicolai Boyarin, I. Shestakovich, R. Čabala","doi":"10.25135/JCM.14.18.02.063","DOIUrl":"https://doi.org/10.25135/JCM.14.18.02.063","url":null,"abstract":"An extensive study concerning the problem of volatile compounds determination in alcoholic products by gas chromatography has been undertaken in the paper. A row of gravimetrically prepared standard solutions was analysed with three analytical methods: traditional method of internal standard, advanced method of internal standard and external standard method. The main analytical characteristics and metrological parameters of the “Ethanol as Internal Standard” method were compared with the traditional approaches. It was shown that this method leads to correct values of volatiles concentrations and the corresponding metrological characteristics are generally better.","PeriodicalId":15343,"journal":{"name":"Journal of Chemical Metrology","volume":null,"pages":null},"PeriodicalIF":1.3,"publicationDate":"2018-06-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47055926","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 : 2018-06-06DOI: 10.25135/jcm.16.18.03.082
S. Oğuzkan, Bora Karagül, E. Aksoy, A. Uzun, Merve Can, H. Yılmaz, H. I. Uğraş, B. Bi̇ni̇ci̇, A. Gören
In this study, mass fractions of paclitaxel, cephalomannine, 10-DAB III and baccatin III in hazelnut were measured with new and validated LC-MS/MS method. Green outer nut husk and nutshell of Turkish hazelnut (Corylus colurna L.) were collected from Düzce, Trabzon, Adapazarı and Samsun at several altitudes during August and September in 2014. The target analytes were prepared using solid-liquid extraction and analysed by LC-MS/MS. High amount of baccatin III, used for synthesizing semi-synthetic paclitaxel, was found in the nutshells collected at 250-500 m altitude in Cumayeri district of Duzce. In the husk samples from Vakfıkebir district of Trabzon, the highest amount of baccatin III was obtained. The mass fractions of baccatin III in nutshell and husks were between 164.38-1020.85 μgkg-1 and 166.12-923.64 μgkg-1, respectively.
{"title":"Determination of taxanes by validated LC-MS/MS method in hazelnut collected from different regions and altitudes in Turkey","authors":"S. Oğuzkan, Bora Karagül, E. Aksoy, A. Uzun, Merve Can, H. Yılmaz, H. I. Uğraş, B. Bi̇ni̇ci̇, A. Gören","doi":"10.25135/jcm.16.18.03.082","DOIUrl":"https://doi.org/10.25135/jcm.16.18.03.082","url":null,"abstract":"In this study, mass fractions of paclitaxel, cephalomannine, 10-DAB III and baccatin III in hazelnut were measured with new and validated LC-MS/MS method. Green outer nut husk and nutshell of Turkish hazelnut (Corylus colurna L.) were collected from Düzce, Trabzon, Adapazarı and Samsun at several altitudes during August and September in 2014. The target analytes were prepared using solid-liquid extraction and analysed by LC-MS/MS. High amount of baccatin III, used for synthesizing semi-synthetic paclitaxel, was found in the nutshells collected at 250-500 m altitude in Cumayeri district of Duzce. In the husk samples from Vakfıkebir district of Trabzon, the highest amount of baccatin III was obtained. The mass fractions of baccatin III in nutshell and husks were between 164.38-1020.85 μgkg-1 and 166.12-923.64 μgkg-1, respectively.","PeriodicalId":15343,"journal":{"name":"Journal of Chemical Metrology","volume":null,"pages":null},"PeriodicalIF":1.3,"publicationDate":"2018-06-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47608430","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 : 2018-06-06DOI: 10.25135/JCM.17.18.05.094
Gulcin H. Ozer, Etil Guzelmeric, Gozde Sezgin, Ercan Ozyurek, Avni Arslan, E. Sezik, E. Yeşilada
{"title":"Comparative determination of ruscogenins content in Butcher’s Broom rhizome samples gathered from the populations grown in different soil conditions in the Marmara Region and attempts for pilot field cultivation of rhizomes","authors":"Gulcin H. Ozer, Etil Guzelmeric, Gozde Sezgin, Ercan Ozyurek, Avni Arslan, E. Sezik, E. Yeşilada","doi":"10.25135/JCM.17.18.05.094","DOIUrl":"https://doi.org/10.25135/JCM.17.18.05.094","url":null,"abstract":"","PeriodicalId":15343,"journal":{"name":"Journal of Chemical Metrology","volume":null,"pages":null},"PeriodicalIF":1.3,"publicationDate":"2018-06-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44607554","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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