The Experts below are selected from a list of 285 Experts worldwide ranked by ideXlab platform
Kyung Ho Row - One of the best experts on this subject based on the ideXlab platform.
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Facile Preparation of an Ionic Liquid Composite Mesoporous Polymer as a Solid Phase Extraction Adsorbent for the Separation and Purification of Flavonoids from Chamaecyparis obtusa
Analytical Letters, 2013Co-Authors: Minglei Tian, Jindong Qiao, Kyung Ho RowAbstract:A new ionic liquid composite mesoporous polymer (ILCMP) was synthesized by one-pot copolymerization. The obtained ILCMP with good morphology, good pore diameter distribution, and high adsorption capacity was successfully applied as the sorbent in solid-phase extraction (SPE) to extract and separate quercitrin and myricetin from Chamaecyparis obtusa. 87.8–101.8% of satisfactory recoveries were obtained with RSDs less than 6.2% and the amounts of quercitrin and myricetin in Chamaecyparis obtusa were 0.38 and 0.12 mg/g, respectively. The proposed ILCMP-SPE-HPLC method was applied for the separation, purification, and determination of flavonoids from natural products.
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simultaneous extraction and separation of flavonols and flavones from Chamaecyparis obtusa by multi phase extraction using an ionic liquid modified microsphere polymer
Phytochemical Analysis, 2012Co-Authors: Minglei Tian, Kyung Ho RowAbstract:Introduction Flavonols and flavones, especially quercitrin, myricetin and amentoflavone, are the main anti-bacterial and anti-cancer compounds in Chamaecyparis obtuse. Multi-phase extraction is a new method that can extract and separate target compounds simultaneously. Objective An amino ionic liquid immobilised microsphere polymer was used as a multi-phase extraction sorbent to extract and separate quercitrin, myricetin and amentoflavone from Chamaecyparis obtusa. Methodology The sorbent and Chamaecyparis obtusa powder were packed into a single cartridge. Using a fixed volume of methanol with five repetitions, the target compounds were extracted from the powder to the sorbent. The sorbent was then washed with n-hexane to remove any interfering species and the target compounds were eluted sequentially using water, methanol and methanol containing 1% acetic acid (vol.). Results Under the optimised conditions, 0.45 mg/g of quercitrin, 0.18 mg/g of myricetin and 0.12 mg/g of amentoflavone from 2.0 g of powder were obtained by multi-phase extraction using 0.3 g of sorbent. Conclusion The method described has a low deviation error, requires a small amount of solvent and is highly selective and reproducible. Copyright © 2012 John Wiley & Sons, Ltd.
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Simultaneous Extraction and Separation of Flavonols and Flavones from Chamaecyparis obtusa by Multi‐phase Extraction using an Ionic Liquid‐modified Microsphere Polymer
Phytochemical analysis : PCA, 2012Co-Authors: Minglei Tian, Kyung Ho RowAbstract:Introduction Flavonols and flavones, especially quercitrin, myricetin and amentoflavone, are the main anti-bacterial and anti-cancer compounds in Chamaecyparis obtuse. Multi-phase extraction is a new method that can extract and separate target compounds simultaneously. Objective An amino ionic liquid immobilised microsphere polymer was used as a multi-phase extraction sorbent to extract and separate quercitrin, myricetin and amentoflavone from Chamaecyparis obtusa. Methodology The sorbent and Chamaecyparis obtusa powder were packed into a single cartridge. Using a fixed volume of methanol with five repetitions, the target compounds were extracted from the powder to the sorbent. The sorbent was then washed with n-hexane to remove any interfering species and the target compounds were eluted sequentially using water, methanol and methanol containing 1% acetic acid (vol.). Results Under the optimised conditions, 0.45 mg/g of quercitrin, 0.18 mg/g of myricetin and 0.12 mg/g of amentoflavone from 2.0 g of powder were obtained by multi-phase extraction using 0.3 g of sorbent. Conclusion The method described has a low deviation error, requires a small amount of solvent and is highly selective and reproducible. Copyright © 2012 John Wiley & Sons, Ltd.
Jessie K. Pearl - One of the best experts on this subject based on the ideXlab platform.
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a late holocene subfossil atlantic white cedar tree ring chronology from the northeastern united states
Quaternary Science Reviews, 2020Co-Authors: Jessie K. Pearl, Charlotte L. Pearson, Neil Pederson, Edward R Cook, Kevin J Anchukaitis, Jeffrey P Donnelly, Mary Lardie C Gaylord, Ann P Mcnichol, George L ZimmermannAbstract:Abstract Tree-rings provide precise annually dated climate information, but their application can be limited by the relatively short lifespan of many trees. To overcome this limitation, tree-ring records can be extended over longer time periods by connecting living trees with older “sub-fossil” trees, which can provide information on longer timescales throughout the Holocene. These long chronologies are proxy records of past climate, provide precise chronological information for extreme events, and give insight into the range of natural climate variability prior to the instrumental period. In the densely populated northeastern United States, few tree-ring records are longer than 500 years, and there are no millennial-length tree-ring chronologies for the region. Here, we use a combination of standard dendrochronological and radiocarbon techniques, including use of the 774 CE radiocarbon excursion, to generate an absolutely dated 2500 year-long tree ring record from living, archaeological, and subfossil Atlantic white cedar (Chamaecyparis thyoides) found in the coastal northeastern United States. Our chronology demonstrates the potential to develop multi-millennial Chamaecyparis thyoides tree-ring records to address previously unanswered questions regarding late Holocene hydroclimate, extreme events, and temperature variability in New England.
Minglei Tian - One of the best experts on this subject based on the ideXlab platform.
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Facile Preparation of an Ionic Liquid Composite Mesoporous Polymer as a Solid Phase Extraction Adsorbent for the Separation and Purification of Flavonoids from Chamaecyparis obtusa
Analytical Letters, 2013Co-Authors: Minglei Tian, Jindong Qiao, Kyung Ho RowAbstract:A new ionic liquid composite mesoporous polymer (ILCMP) was synthesized by one-pot copolymerization. The obtained ILCMP with good morphology, good pore diameter distribution, and high adsorption capacity was successfully applied as the sorbent in solid-phase extraction (SPE) to extract and separate quercitrin and myricetin from Chamaecyparis obtusa. 87.8–101.8% of satisfactory recoveries were obtained with RSDs less than 6.2% and the amounts of quercitrin and myricetin in Chamaecyparis obtusa were 0.38 and 0.12 mg/g, respectively. The proposed ILCMP-SPE-HPLC method was applied for the separation, purification, and determination of flavonoids from natural products.
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simultaneous extraction and separation of flavonols and flavones from Chamaecyparis obtusa by multi phase extraction using an ionic liquid modified microsphere polymer
Phytochemical Analysis, 2012Co-Authors: Minglei Tian, Kyung Ho RowAbstract:Introduction Flavonols and flavones, especially quercitrin, myricetin and amentoflavone, are the main anti-bacterial and anti-cancer compounds in Chamaecyparis obtuse. Multi-phase extraction is a new method that can extract and separate target compounds simultaneously. Objective An amino ionic liquid immobilised microsphere polymer was used as a multi-phase extraction sorbent to extract and separate quercitrin, myricetin and amentoflavone from Chamaecyparis obtusa. Methodology The sorbent and Chamaecyparis obtusa powder were packed into a single cartridge. Using a fixed volume of methanol with five repetitions, the target compounds were extracted from the powder to the sorbent. The sorbent was then washed with n-hexane to remove any interfering species and the target compounds were eluted sequentially using water, methanol and methanol containing 1% acetic acid (vol.). Results Under the optimised conditions, 0.45 mg/g of quercitrin, 0.18 mg/g of myricetin and 0.12 mg/g of amentoflavone from 2.0 g of powder were obtained by multi-phase extraction using 0.3 g of sorbent. Conclusion The method described has a low deviation error, requires a small amount of solvent and is highly selective and reproducible. Copyright © 2012 John Wiley & Sons, Ltd.
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Simultaneous Extraction and Separation of Flavonols and Flavones from Chamaecyparis obtusa by Multi‐phase Extraction using an Ionic Liquid‐modified Microsphere Polymer
Phytochemical analysis : PCA, 2012Co-Authors: Minglei Tian, Kyung Ho RowAbstract:Introduction Flavonols and flavones, especially quercitrin, myricetin and amentoflavone, are the main anti-bacterial and anti-cancer compounds in Chamaecyparis obtuse. Multi-phase extraction is a new method that can extract and separate target compounds simultaneously. Objective An amino ionic liquid immobilised microsphere polymer was used as a multi-phase extraction sorbent to extract and separate quercitrin, myricetin and amentoflavone from Chamaecyparis obtusa. Methodology The sorbent and Chamaecyparis obtusa powder were packed into a single cartridge. Using a fixed volume of methanol with five repetitions, the target compounds were extracted from the powder to the sorbent. The sorbent was then washed with n-hexane to remove any interfering species and the target compounds were eluted sequentially using water, methanol and methanol containing 1% acetic acid (vol.). Results Under the optimised conditions, 0.45 mg/g of quercitrin, 0.18 mg/g of myricetin and 0.12 mg/g of amentoflavone from 2.0 g of powder were obtained by multi-phase extraction using 0.3 g of sorbent. Conclusion The method described has a low deviation error, requires a small amount of solvent and is highly selective and reproducible. Copyright © 2012 John Wiley & Sons, Ltd.
George L Zimmermann - One of the best experts on this subject based on the ideXlab platform.
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a late holocene subfossil atlantic white cedar tree ring chronology from the northeastern united states
Quaternary Science Reviews, 2020Co-Authors: Jessie K. Pearl, Charlotte L. Pearson, Neil Pederson, Edward R Cook, Kevin J Anchukaitis, Jeffrey P Donnelly, Mary Lardie C Gaylord, Ann P Mcnichol, George L ZimmermannAbstract:Abstract Tree-rings provide precise annually dated climate information, but their application can be limited by the relatively short lifespan of many trees. To overcome this limitation, tree-ring records can be extended over longer time periods by connecting living trees with older “sub-fossil” trees, which can provide information on longer timescales throughout the Holocene. These long chronologies are proxy records of past climate, provide precise chronological information for extreme events, and give insight into the range of natural climate variability prior to the instrumental period. In the densely populated northeastern United States, few tree-ring records are longer than 500 years, and there are no millennial-length tree-ring chronologies for the region. Here, we use a combination of standard dendrochronological and radiocarbon techniques, including use of the 774 CE radiocarbon excursion, to generate an absolutely dated 2500 year-long tree ring record from living, archaeological, and subfossil Atlantic white cedar (Chamaecyparis thyoides) found in the coastal northeastern United States. Our chronology demonstrates the potential to develop multi-millennial Chamaecyparis thyoides tree-ring records to address previously unanswered questions regarding late Holocene hydroclimate, extreme events, and temperature variability in New England.
Shin-ichi Yamamoto - One of the best experts on this subject based on the ideXlab platform.
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Applications of the New Remote Sensing Method to the Forest Biomass Estimation in an Old – Growth Chamaecyparis Obtusa Stand, in the Akazawa Forest Reserve
2013Co-Authors: Nan Wang, Masato Katoh, Shin-ichi Yamamoto, Naoyuki Nishimura, Daisuke HoshinoAbstract:For accurate measurement of forest biomass in the Akazawa Forest Reserve, this study analyzed texture measures derived from GeoEye-1 satellite data using the individual tree crown (ITC) method. On this basis, canopy area, tree tops and tree species of individual trees were delineated. Canopy area was used to calculate the DBH of trees in canopy layer based on canopy-DBH curve in this stand. In this study, the estimation models, between DBH and height, and between canopy area and DBH were developed by linear regression using forest survey data. Then according to the results of satellite data interpreted the biomass of every tree was calculated by biomass expansion factor (BEF). This method was verified against the survey data from old–growth Chamaecyparis obtusa stand composed of various cover types. For Chamaecyparis obtusa, the accuracy of biomass estimation was higher than 84%. However, the accuracy of Chamaecyparis pisifera was less than 60%, because some Chamaecyparis pisifera trees were misidentified as Chamaecyparis obtusa, and canopy area of Chamaecyparis pisifera was underestimated in the high-density stand. For Thujopsis dolabrata, the accuracy ranged from 22.4 % to 78.9%, and from 63.4% to 84.6% for broad-leaved trees, because many of them were understory. These results indicated that estimation of old-growth forest biomass based on high resolution satellite data, might be validated for estimating biomass at the individual tree level improved by developing and applying forest stratum–specific models with the ITC-survey data as a bridging reference in addition to spectral information. This approach is useful for biomass estimation whether is used to calculate biomass of individual tree or forest.
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Development of tree growth prediction with gray model in an old - growth Chamaecyparis obtusa stand, in the Akazawa Forest Reserve
2012Co-Authors: Nan Wang, Masato Katoh, Shin-ichi Yamamoto, Naoyuki Nishimura, Daisuke HoshinoAbstract:Akazawa Reserve Forest in kiso town is a precious forest for research of science and well protected all the time. Hinoki is the dominant tree species whose age about 300 years used to construct the palace in past mainly. In 1988 a plot of 4 hectares was established and the survey had been done periodically in the following 20 years. In this research, we used the collected data of the growth of tree individuals and the stand. Recently in Japan the long rotation management process of conifer plantation is being popular. The collected past and present dataset through this process plays a very important role for the future prediction of forest resource. With the gray theory of mathematics, this research developed a program of calculating tree growth by using the data of the stand surveyed in 1988, 1998, 2003 and 2008. By this program a prediction has been made for the growth of the tree stand in year 2018, 2028 and 2038 respectively. In the understory, the average forecast error of Chamaecyparis obtusa was 23.8% in 1998, 18.6% in 2003 and 11.9% in 2008. For Thujopsis dolabrata , it was 15.8% 13.6% and 9.7% respectively in the three years. And broad-leaved trees’ error was 17.6%, 12.9% and 10.7% in 1998, 2003 and 2008. In middle layer, Chamaecyparis obtusa ’s errors were 22.8%, 16.8% and 8.9% respectively, while they were 16.5%, 18.5% and 11.3% for Thujopsis dolabrata , and 14.9%, 11.9%, 8.7% for broad-leaved trees. In the dominant layer, they were 22.4%, 13.6%, 6.8% for Chamaecyparis obtusa , 9.8%, 13.5%, 17.9% for Thujopsis dolabrata , and 15.6%, 12.8%, 8.9% for broad-leaved trees in the specified years respectively.
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Stem distribution and clonal structure of Chamaecyparis pisifera growing in an old-growth beech-conifer forest
Ecological Research, 2004Co-Authors: Takehiro Hayakawa, Nobuhiro Tomaru, Shin-ichi YamamotoAbstract:To elucidate sapling patch formation and the mode of regeneration occurring in Chamaecyparis pisifera, we investigated stem distribution and clonal structure of this species in an old-growth beech-conifer forest in central Japan. The study was carried out in a 1-ha plot using small and large sapling (d.b.h.
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Effects of canopy conditions on the regeneration of major tree species in an old-growth Chamaecyparis obtusa forest in central Japan
Forest Ecology and Management, 2002Co-Authors: Daisuke Hoshino, N Nishimura, Shin-ichi YamamotoAbstract:Abstract The regeneration mode of major tree species (Chamaecyparis obtusa (Sieb. et Zucc.) Endl., Thujopsis dolabrata Sieb. et Zucc., Chamaecyparis pisifera (Sieb. et Zucc.) Endl., Quercus mongolica Fischer ex Turcz., Magnolia obovata Thunb. and Betula grossa Sieb. et Zucc.) in relation to four canopy conditions (closed evergreen conifer canopy, closed evergreen conifer canopy adjacent to canopy gap (gap-adjacent), canopy gap, and closed deciduous broad-leaved tree (DBL) species canopy) was studied from 1988 to 1998 in a 4-ha permanent plot in the Akasawa Forest Reserve, central Japan. The vertical distribution of stems and the major species composition in four height (canopy; ≥25 m tall overtopping neighboring trees, subcanopy; ≥25 m tall, middle; ≥10 m tall, and understory;