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Synthesis and characterization of yellow water-borne polyurethane using a diol colorant as extender

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Chinese Chemical Letters 2010年第2期21卷 143-145页

作者： Zhang, He Zhang, xing yuan Dai, Jia Bing Li, Wei Hu Univ Sci & Technol China Dept Polymer Sci & Engn CAS Key Lab Soft Matter Chem Hefei 230026 Peoples R China

A novel and facile method toward a series of yellow water-borne polyurethane was developed by using an intrinsically colored diol in this *** yellow aqueous dispersion PCLD-HENA-PU was synthesized based on isophorone diisocyanate(IPDI), polycaprolactonediol(PCLD) and 2,2-dimethylol propionic acid(DMPA) using a yellow diol N,N-bis(2-hydroxyethyl)-4-nitroaniline (HENA) as a chain *** to the complete reaction of OH group in colorant HENA with NCO group in diisocyanate,a series of stable yellow p...

关键词： Colored diol Extender Polycaprolactonediol N N-bis(2-hydroxyethyl)-4-nitroaniline Yellow polyurethane

Prediction of water table depths under soil water-groundwater interaction and stream water conveyance

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Science China Earth Sciences 2011年第3期54卷 420-430页

作者： DI ZhenHua XIE ZhengHui yuan xing TIAN XiangJun LUO ZhenDong CHEN YaNing ICCES/LASG Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China School of Science Beijing Jiaotong University Beijing 100044 China Department of Mathematics & Physics North China Electric Power University Beijing 102206 China Key Laboratory of Oasis Ecology and Desert Environment Xinjiang Institute of Ecology and Geography Chinese Academy of Sciences Urumqi 830011 China

Water table over an arid region can be elevated to a critical level to sustain terrestrial ecosystem along the natural channel by the stream water conveyance. Estimation of water table depth and soil moisture on river channel profile may be reduced to a two-dimensional moving boundary problem with soil water-groundwater interaction. The two-dimensional soil water flow with stream water transferred is divided into an unsaturated vertical soil water flow and a horizontal groundwater flow. Therefore, a prediction model scheme for water table depths under the interaction between soil water and groundwater with stream water transferred is presented, which includes a vertical soil water movement model, a horizontal groundwater movement model, and an interface model. The synthetic experiments are conducted to test the sensitivities of the river elevation, horizontal conductivity, and surface flux, and the results from the experiments show the robustness of the proposed scheme under different conditions. The groundwater horizontal conductivity of the proposed scheme is also calibrated by SCE-UA method and validated by data collected at the Yingsu section in the lower reaches of the Tarim River, which shows that the model can reasonably simulate the water table depths.

关键词： stream water conveyance soil water-groundwater interaction model SCE-UA method

Correlation Study of Toxicity of Substituted Phenols to River Bacteria and Their Biodegradability in River Water

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Biomedical and Environmental Sciences 2005年第5期18卷 281-285页

作者： xing yuan GUANG-HUA LU LI-MIN SU Department of Environmental Science Northeast Normal University Changchun 130024 Jilin China College of Environmental Science and Engineering Hohai University Nanjing 210098 Jiangsu China

To study the correlation of toxicity with biodegradability （BODT） in order to promote QSBR development and understand the degradation mechanism. Methods Toxicity of substituted phenols to river bacteria was determined by the turbidities that were measured using a spectrophotometer （UV-190） at 530 nm against a blank control. The biodegradability of substituted phenols was expressed as BODT and the DO concentrations were determined by the iodometric titration method. Results The BODT and toxicity（log 1/IC50） of 12 substituted phenols to bacteria from the Songhua River were determined respectively. The correlation of biodegradability with toxicity was developed： BODT=8.21 （±2.22） pKa -32.44 （±8.28） log 1/IC50 ＋89.04 （±38.20）, n=12, R^2=0.791, R^2（adj）=0.745, SE=9.134, F=17.066, P=0.001. Conclusion The BODT of substituted phenols was influenced by their toxicity and the ionization constant pKa. The stronger the toxicity, the less readily the compound was degraded by river bacteria.

关键词： Biodegradability Toxicity Correlation Substituted phenols

Whole-genome identification and expression analysis of K^+ efflux antiporter(KEA) and Na^+/H^+ antiporter(NHX) families under abiotic stress in soybean

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Journal of Integrative Agriculture 2015年第6期14卷 1171-1183页

作者： CHEN Hua-tao CHEN Xin WU Bing-yue yuan xing-xing ZHANG Hong-mei CUI Xiao-yan LIU Xiao-qing Institute of Vegetable Crops Jiangsu Academy of Agricultural Sciences

Sodium toxicity and potassium insufficient are important factors affecting the growth and development of soybean in saline soil. As the capacity of plants to maintain a high cytosolic, K^＋/Na^＋ ratio is the key determinant of tolerance under salt stress. The aims of the present study were to identify and analyse expression patterns of the soybean K^＋ efflux antiporter（KEA） gene and Na^＋/H^＋ antiporter（NHX） gene family, and to explore their roles under abiotic stress. As a result, 12 soybean Gm KEAs genes and 10 soybean Gm NHXs genes were identified and analyzed from soybean genome. Interestingly, the novel soybean KEA gene Glyma16g32821 which encodes 11 transmembrane domains were extremely up-regulated and remained high level until 48 h in root after the excessive potassium treatment and lack of potassium treatment, respectively. The novel soybean NHX gene Glyma09g02130 which encodes 10 transmembrane domains were extremely up-regulated and remained high level until 48 h in root with Na Cl stress. Imaging of subcellular locations of the two new Glyma16g32821-GFP and Glyma09g02130-GFP fusion proteins indicated all plasma membrane localizations of the two novel soybean genes. The 3D structures indicated that the two soybean novel proteins Glyma09g02130（NHX） and Glyma16g32821（KEA） all belong to the cation/hydrogen antiporter family.

关键词： soybean KEA NHX and Na antiporter abiotic potassium extremely transmembrane maintain

Advances in salinity tolerance of soybean: Genetic diversity, heredity, and gene identification contribute to improving salinity tolerance

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Journal of Integrative Agriculture 2018年第10期17卷 2215-2221页

作者： CHEN Hua-tao LIU Xiao-qing ZHANG Hong-mei yuan xing-xing GU He-ping CUI Xiao-yan CHEN Xin Institute of Industrial Crops Jiangsu Academy of Agricultural Sciences

Salt stress is one of the major abiotic stresses affecting soybean growth. Genetic improvement for salt tolerance is an effective way to protect soybean yield under salt stress conditions. Successful improvement of salt tolerance in soybean relies on identifying genetic variation that confers tolerance in soybean germplasm and subsequently incorporating these genetic resources into cultivars. In this review, we summarize the progress in genetic diversity and genetics of salt tolerance in soybean, which includes identifying genetic diversity for salt tolerant germplasm; mapping QTLs conferring salt tolerance; map-based cloning; and conducting genome-wide association study（GWAS） analysis in soybean. Future research avenues are also discussed, including high throughput phenotyping technology, the CRISPR/Cas9 Genome-Editing System, and genomic selection technology for molecular breeding of salt tolerance.

关键词： soybean genetic variation heredity gene identification salinity improvement

Synthesis of a Novel UV Curable Aqueous Dispersion Polyurethane PDHA-PEDA-PU and the Properties of Cured Film

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Chinese Chemical Letters 2006年第3期17卷 369-372页

作者： Chen Yan BAI xing yuan ZHANG Jia Bing DAI Wei Hu LI Department of Polymer Science and Engineering University of Science and Technology of China Hefei 230026

A novel ultraviolet （UV） curable aqueous dispersion polyurethane PDHA-PEDA-PU was synthesized based on isophorone diisocyanate （IPDI）, polyester dihydric alcohol （PDHA）, dimethylol propionic acid （DMPA）, pentaerythritol diacrylate （PEDA）, 2-hydroxyethyl acrylate （HEA） and triethylamine （TEA）. Acrylate groups were incorporated in the side and end of PDHA-PEDA-PU chain. The C=C content in the chain can be controlled easily through the change of IPDI/PDHA/PEDA ratio. Fourier transform infrared spectroscopy （FTIR） was used to identify the structure of prepolymer, aqueous dispersion and cured polyurethane. The curing rule of the polyurethane for different C=C content has been investigated depending on the change of C=C content during the curing process. The hardness, thermal stability and scrub resistance to MEK of UV cured PDHA-PEDA-PU were also discussed for the samples with different C=C content.

关键词： UV curable aqueous dispersion polyurethane

Mixing of Racemic Poly(L-lactide)/Poly(D-lactide) Blend with Miscible Poly(D,L-lactide):Toward All Stereocomplex-type Polylactide with Strikingly Enhanced SC Crystallizability

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Chinese Journal of Polymer Science 2021年第11期39卷 1470-1480页

作者： Yi-Long Ju Xiang-Li Li xing-yuan Diao Hong-Wei Bai Qin Zhang Qiang Fu College of Polymer Science and Engineering State Key Laboratory of Polymer Materials EngineeringSichuan UniversityChengdu 610065China

Stereocomplex-type polylactide(SC-PLA)consisting of alternatively arranged poly(L-lactide)(PLLA)and poly(D-lactide)(PDLA)chains has gained a good reputation as a sustainable engineering plastic with outstanding heat resistance and durability,however its practical applications have been considerably hindered by the weak SC *** methods used to enhance the SC crystallizability are generally achieved at the expense of the precious bio-renewability and/or bio-degradability of ***,we demonstrate a feasible method to address these challenges by incorporating small amounts of poly(D,L-lactide)(PDLLA)into linear high-molecular-weight PLLA/PDLA *** results show that the incorporation of the atactic PDLLA leads to a significant enhancement in the SC crystallizability because its good miscibility with the isotactic PLAs makes it possible to greatly improve the chain mixing between PLLA and PDLA as an effective ***,the melt stability(i.e.,the stability of PLLA/PDLA chain assemblies upon melting)could also be improved *** intriguingly,SC crystallites are predominantly formed with increasing content and molecular weight of *** notably,exclusive SC crystallization can be obtained in the racemic blends with 20 wt%PDLLA having weight-average molecular weight of above 1×10^(5)g/mol,where the chain mixing level and intermolecular interactions between the PLA enantiomers could be strikingly ***,our work could not only open a promising horizon for the development of all SC-PLA-based engineering plastic with exceptional SC crystallizability but also give a fundamental insight into the crucial role of PDLLA in improving the SC crystallizability of PLLA/PDLA blends.

关键词： Polylactide Stereocomplex Crystallization Melt stability Melt memory

Incorporating Exercise Efficiency to Evaluate the Accessibility and Capacity of Medical Resources in Tibet, China

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Chinese Geographical Science 2023年第1期33卷 175-188页

作者： WANG Li YANG Linsheng WEI Binggan LI Hairong CAI Hongyan HUANG Jixia yuan xing Key Laboratory of Land Surface Pattern and Simulation Institute of Geographical Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China College of Resources and Environment University of Chinese Academy of SciencesBeijing 100049China State Key Laboratory of Resources and Environmental Information System Institute of Geographical Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China Key Laboratory for Silviculture and Conservation of Ministry of Education Beijing Forestry UniversityBeijing 100083China

Accessibility and capacity of medical resources are key for the health care and emergency response, while the efficiency of the medical resources is very much limited by hypoxia in Tibet, *** introducing exercise efficiency, this study explores the accessibility of township residence to county-ship medical resources in Tibet using weighted mean travel time(WMT), and evaluates the medical capacity *** results show that: 1) the average travel time of township residence to county-level hospital is around2 h by motor vehicle in *** than half of the population can not reach the county-ship hospital within 1 h, 33.24% of the population can not reach within 2 h, and 3.75% of the population can not reach within 6 h.2) When considering the catchment of the medical resources and the population size, the WMT of the county-ship medical resources ranges from 0.25 h to 10.92 h.3) After adjusted by travel time and exercise efficiency, the county-ship medical capacity became more unequal, with 38 out of 74 counties could not meet the national guideline of 1.8 medical beds per 1000.4) In total, there are 17 counties with good WMT and sufficient medical resources,while 13 counties having very high WMT and low capacity of medical resources in *** the end, suggestions on medical resources relocation and to improve the capacity are *** study provides a method to incorporate exercise efficiency to access the accessibility and evaluate medical capacity that can be applied in high altitude ranges.

关键词： exercise efficiency medical resources medical capacity Tibet

Physical Insight for Grafting Polymer Chains onto the Substrate via Computer Simulations:Kinetics and Property

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Chinese Journal of Polymer Science 2022年第7期40卷 817-833页

作者： Chi-Xin Liang Hui Lu Bai-Ying Huang Ji-yuan xing Feng-Long Gu Hong Liu School of Chemistry South China Normal UniversityKey Laboratory of Theoretical Chemistry of Environment Ministry of EducationGuangzhou510006China State Key Laboratory of Supramolecular Structure and Materials Institute of Theoretical ChemistryCollege of ChemistryJilin UniversityChangchun130023China State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun130022China

Molecules adsorbed or attached on a surface is a quite basic phenomenon in numerous chemical or biological ***-onto is considered as a feasible way to achieve *** grafting reaction is essentially controlled by the diffusion of the molecules,thus it is more likely a physical issue,instead of a chemical *** of the experimental difficulty in measuring the properties of surface-attached molecules(e.g.,the polymeric molecules),the surface-bound molecules are often assumed as with the same properties as that of the start feeding ones in *** assumption was even used to guide further characterization,while it is proved to be invalid by different quantifying ***,an effective prediction for the properties of surface-bound molecules is still *** on a microscopic level and a dynamic perspective,the grafting process onto a flat substrate with polydisperse feeding polymeric molecules is investigated in-depth by coarse-grained Brownian dynamics simulation as well as model *** find from simulations that for the final grafting densityσ_(g)and the mean chain length of start feeding molecules,the dependence ofσ_(g)-^(γ)with the constant exponential factorγmay be a determined rule for one-end functionalized flexible linear polymer chains grafting on the flat *** grafting-onto is a multiple interplayed process,our simulation study indicates that there is an optimized initial concentration of start feeding molecules for achieving high grafting density of surface-bound *** also propose a correctional equation to quantitatively predict the molecular weight distribution(MWD)of surface-bound polymeric molecules,which may be effective for predicting the MWD of the surface-bound ones in specific *** simulation study helps to better understand the kinetics of grafting-onto process,and serves as a theoretical guide to achieve the precise design of surface modification materials vi

关键词： Grafting-onto Grafting density Polydisperse Molecular weight distribution