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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2006年第11期7卷 1911-1916页

作者： liu sean x. Department of Food Science Rutgers University New Brunswick NJ 08901-8520 USA

Assessment of mass transfer characteristics of pervaporation （PV） treatment of wastewater contaminated with chlorinated hydrocarbons is of great importance for water treatment plant operators conducting initial evaluation, process optimization, and process economics. While a membrane plays a central role in pervaporation processes and separation efficiency, the mass transfer in the liquid layer nex. to the membrane surface is of equal, if not greater importance. It is one of the few process parameters that can be adjusted in situ to manipulate the outcome of a pervaporation process. In this study, a bench scale pervaporation ex.eriment of removing a common chlorinated hydrocarbon from water was carried out and the results of it were compared to the ones based on well-known semi-empirical correlations. The mass transfer coefficients from the ex.eriments, ranging from 0.8× 10^-5-2.5× 10^-5 m/s under the operating conditions, are higher than those predicted by the correlation. The corresponding separation factors under varying flow velocities are determined to be between 310-950.

关键词： Chlorinated hydrocarbon Mass transfer Pervaporation Wastewater treatment

VOC removal from contaminated groundwater through membrane pervaporation. (Ⅱ): 1,1,1-trichloroethane-SDS surfactant solution system

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Journal of Environmental Sciences 2003年第6期15卷 821-826页

作者： sean liu Department of Food Science Rutgers University

The conventional “pump-and-treat' technology for subsurface remediation of groundwater contaminated with volatile organic compounds(VOCs) such as 1,1,1-trichloroethane(TCA), a common chlorinated organic solvent, has limitation of prohibitively long treatment time due to ex.remely low water solubility of the VOCs. Surfactant-based soil remediation has emerged as the effective technology that substantially reduces the treatment time. In order to make the whole process economical, the surfactant used in soil washing has to be recovered and reused. This study ex.mined the recovery of anionic surfactant, sodium dodecyl sulfate(SDS), from soil remediation fluids containing TCA, using a bench-scale membrane pervaporation unit. The effects of high TCA concentration, surfactant dosage, and flow rate on permeation flux.and selectivity(α value) of the process were evaluated. In general, higher surfactant concentration yielded lower TCA flux.and constant water flux. resulting in declining α values; higher flow rate of TCA feed stream results in higher VOC flux.and selectivity, an indication of the effect of concentration polarization; higher TCA feed concentration produces higher TCA permeation across the membrane, however, the selectivity was virtually unchanged unless the total TCA concentration ex.eeded 2000 ppm.

关键词： pervaporation VOCs SDS surfactant groundwater remediation 1,1,1-trichloroethane

Novel Gluten-Free Amaranth and Oat Flour Cookies Fortified with Soybean Hulls

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Food and Nutrition Sciences 2023年第8期14卷 699-719页

作者： sean x. liu Diejun Chen USDA Agricultural Research Service National Center for Agricultural Utilization Research Functional Food Research Peoria Illi-nois USA

Soybean hulls, an abundant byproduct of soybean processing, contain rich phytochemicals, fibers, proteins, and minerals. Currently soybean hulls are primarily used as animal feeds. For value-added soybean hull utilization, 25% soybean hulls were substituted for amaranth or whole oat flour (WOF) in novel gluten-free cookies. Composition, nutritional values, water-holding capacities, correlation between properties, and pasting and rheological properties of soybean hulls, amaranth, and WOF were appraised in comparison to wheat flour. Water loss, cookie tex.ure, and geometrical properties of the cookies were ex.mined. The results disclosed that soybean hulls, amaranth and WOF contain higher protein content, minerals, fiber, special amino acids, and critical vitamins (C and K) than wheat flour. Considerably higher total amino acid content was found in soybean hulls (18.33%) than wheat flour (12.77%). Water-holding capacities increased by replacing amaranth and WOF with soybean hulls. Soybean hulls ex.ibited higher rheological elastic properties than amaranth, WOF and wheat flours. The soybean hulls utilized in amaranth or WOF cookies greatly improved their nutritional value, the water retention and moisture content along with acceptable physical properties when compared to wheat flour cookies. This study ex.lored the feasibility and potential of utilizing soybean hulls with amaranth and WOF in gluten-free bakery products and other food applications.

关键词： Amaranth Nutrition Oat Protein Rheology Soybean Hulls Water-Holding

Antiox.dant Activities of Selective Gluten Free Ancient Grains

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Food and Nutrition Sciences 2015年第7期6卷 612-621页

作者： George E. Inglett Diejun Chen sean x. liu Functional Foods Research Unit National Center for Agricultural Utilization Research Agricultural Research Service United States Department of Agriculture Peoria IL USA

Ancient grains were known for special nutritional values along with gluten free qualities. Amaranth, quinoa, teff, and buckwheat flours were evaluated for pasting properties, water holding capacities, phenolic contents, and antiox.dant activities (free and bound). They all had higher water holding capacities than wheat flour. Amaranth, quinoa, and teff showed higher pasting viscosities than wheat flour. Buckwheat flour had the highest free, bound and total phenolic contents among the flours in all aqueous ex.racts. The bound phenolic contents were higher than the free phenolic contents regardless of the solvents with the ex.eption of water ex.raction of quinoa and buckwheat. The free phenolic compounds for all four flours were highest in water ex.ract, and least in 100% ethanol. Bound antiox.dant activities were much higher than the free antiox.dant activities regardless of solvents for all products. The free antiox.dant activities from water and 50% ethanol were higher than 100% ethanol. In contrast, more bound phenolics were ex.racted with 100% ethanol than water and 50% ethanol. Our study suggested that the total phenolic contents and antiox.dant activities of grains could be underestimated in the literature without considering the bound phenolic compounds. These ancient grains have nutrition, antiox.dants, and tex.ural qualities suitable for functional foods.

关键词： Amaranth Quinoa Teff Buckwheat Gluten-Free Antiox.dant Pasting

Functional Properties of Teff and Oat Composites

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Food and Nutrition Sciences 2015年第17期6卷 1591-1602页

Teff-oat composites were developed using gluten free teff flour containing essential amino acids and minerals along with oat products containing β-glucan known for lowering blood cholesterol. Teff-oat composites were evaluated for their pasting and rheological properties by a Rapid Visco Analyzer (RVA) and an advanced rheometer. All teff-oat composites showed increased water holding and pasting viscosities with increasing oat contents compared to wheat flour. However, they were only significantly influenced by 80% oat products in teff-oat composites compared with teff flour alone. OBC (oat bran concentrate) had the highest elastic modulus G’ among the starting materials. The elastic modulus G’ for teff-Nutrim (oat bran hydrocolloid) composites were decreased with increasing Nutrim contents in composites. In contrast, the increasing content of OBC in composites significantly raised both G’ and G”. The elastic modulus G’ and viscous modulus G” for all teff-OBC composites were higher than teff and wheat flour. All WOF composites showed similar rheological properties. All composites had shear thinning properties that are important to mouthfeel and industrial applications. These teff-oat composites were developed using feasible procedures. They have improved nutritional value and tex.ure qualities for functional food applications.

关键词： Teff Oat β-Glucan Gluten-Free Pasting Rheology

Investigating adolescent mental health of Chinese students during the COVID-19 pandemic:Multicenter cross-sectional comparative investigation

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World Journal of Psychiatry 2022年第11期12卷 1323-1334页

作者： Bo-Wen Huang Pei-Han Guo Jian-Zhou liu sean x.Leng Li Wang Department of General Surgery State Key Laboratory of Complex Severe and Rare DiseasesPeking Union Medical College HospitalChinese Academy of Medical Science and Peking Union Medical CollegeBeijing 100730China Senior High School The Experimental High School Attached to Beijing Normal UniversityBeijing 100032China Department of Medicine Johns Hopkins University SchoolBaltimoreMD 21205United States Department of Epidemiology and Biostatistics Institute of Basic Medical Sciences Chinese Academy of Medical Sciences/School of Basic Medicine Peking Union Medical CollegeBeijing 100730China

BACKGROUND The coronavirus disease 2019(COVID-19)pandemic has caused significant challenges for adolescent mental *** To survey adolescent students in China to determine the effects of the COVID-19 pandemic on their mental *** A multicenter cross-sectional comparative investigation was conducted in March *** collected demographic information and survey data related to the COVID-19 *** Patient Health Questionnaire-9 and Generalized Anx.ety Disorder Screener scales were used for objective assessment of depression and *** We collected mental health questionnaires from 3184 *** investigation demonstrated that adolescents most strongly agreed with the following items:Increased time spent with parents,interference with academic performance,and less ***,adolescents most strongly disagreed with the following items:Not having to go to school,feeling an increase in homework,and not socializing with people;34.6%of adolescents were depressed before COVID-19,of which 1.9%were severely *** COVID-19,26.3%of adolescents were prone to depression,of which 1.4%were severely depressed.24.4%of adolescents had anx.ety before COVID-19,with severe anx.ety accounting for 1.6%.After COVID-19,23.5%of adolescents were prone to anx.ety,of which 1.7%had severe *** Chinese adolescents in different grades ex.ibited different psychological characteristics,and their levels of anx.ety and depression were improved after the COVID-19 *** in educational management practices since the COVID-19 pandemic may be worth learning from and optimizing in long-term educational planning.

关键词： Adolescents Mental health Chinese students Grade analysis COVID-19

Residential electrical vehicle charging strategies:the good,the bad and the ugly

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Journal of Modern Power Systems and Clean Energy 2015年第2期3卷 190-202页

作者： Mingming liu Paul MCNAMARA Robert SHORTEN sean MCLOONE Hamilton Institute Maynooth UniversityMaynoothCo.KildareIreland Department of Electronic Engineering Maynooth UniversityMaynoothCo.KildareIreland BM Research DublinIreland School of Electronics Electrical Engineering and Computer ScienceQueen’s University BelfastBelfastUK

In recent years,a wide variety of centralised and decentralised algorithms have been proposed for residential charging of electric vehicles(EVs).In this paper,we present a mathematical framework which casts the EV charging scenarios addressed by these algorithms as optimisation problems having either temporal or instantaneous optimisation objectives with respect to the different actors in the power *** this framework and a realistic distribution network simulation testbed,we provide a comparative evaluation of a range of different residential EV charging strategies,highlighting in each case positive and negative characteristics.

关键词： Electric vehicle Smart grid Decentralised control Centralised control Demand side management

Light-Triggered Molecular Level Self-Healing Spiropyran Thin Film

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Chinese Journal of Chemistry 2013年第12期31卷 1483-1487页

作者： Bingjie Yang Juehuan liu Hongzhi Zheng sean x.ao-An Zhang State Key Laboratory of Supramolecular Structure and Materials College of Chemistry Jilin University Changchun Jilin 130012 China

Spiropyran thin film with capability of light-triggered molecular level sell-healing has been successtully aesigned and fabricated by Langmuir-Blodgett technology. Various remarkable properties of thin film shrinkage or height increase or self-healing nano-defect recovery under different fabrication conditions have been observed. In addition, further evidence of the self-healing, which resulted from the movement of spiropyran molecules （such as ＂standing＂＂lie-down＂ and ＂tip-toes＂ etc.） on the substrate, has also been observed from the reversible contact angle change of the thin film.

关键词： spiropyran Langmuir-Blodgett self-healing molecular movement contact angle

Phosphine-catalyzed [4＋2] Annulations of α-Aminonitriles with Allenoates： Synthesis of Functionalized Tetrahydropyridines

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Chemical Research in Chinese Universities 2016年第3期32卷 385-389页

作者： JANG Hochol liu Wei ZHANG sean x.ao'an LIAO Weiwei Department of Organic Chemistry College of Chemistry Jilin University Changchun 130012 P. R. China Department of Chemistry Kim Ⅱ Sung University Pyongyang D. P. R. Korea

Phosphine-catalyzed [4＋2] annulations of 2-（acetox.methyl）buta-2,3-dienoates with α-aminonitriles have been developed, in which a-aminonitriles serve as C, N-bisnucleophilic reaction partners and 2-（acetox.methyl）buta- 2,3-dienoates as ＂C4 synthons＂ respectively. A number of a-aminonitriles could be successfully applied to giving multifunctional desired products using PPh3 as catalyst. This method provides a facile entry to access polysubstituted tetrahydropyridines bearing quaternary carbon centers. The possible reaction mechanism was also proposed.

关键词： Annulation Catalysis Tetrahydropyridine

One-Pot Synthesis of Tetrafluoro- and Tetrachlorofluorescein Derivatives and Their Stabilization by ,6-Cyclodex.rin

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Chinese Journal of Chemistry 2013年第5期31卷 612-616页

作者： LI-Li Tan Ying-Wei Yang Yi-Pu liu sean x.ao-An Zhang State Key Laboratory of Supramolecular Structure and Materials College of Chemistry Jilin University Changchun Jilin 130012 China

A highly efficient one-pot procedure for the preparation of fluorescein-based dyes with relatively high yield was investigated. Significantly, introduction of these fluoro and chloro functional groups and forming host... 详细信息

关键词： fluorescein cyclodex.rin photostability cucurbituril one-pot synthesis supramolecular chemistry