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A convenient method for the determination of molecular weight cut-off of ultrafiltration membranes

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Chinese Journal of Chemical Engineering 2017年第1期25卷 62-67页

作者： Cunyu li yun Ma Hongyang li Guoping peng Pharmacy College Nanjing University of Chinese Medicine Nanjing 210023 China Jiangsu Collaborative Innovation Center of Chinese Medicinal Resources Industrialization Nanjing 210023 China

With the rapid increase of water contamination,membrane separation technology and their corresponding molecular weight cut-off(MWCO) evaluation method become more *** this study,Panax notoginseng saponins was used as a new standard marker to determinate ultrafiltration(UF) membrane MWCOs,series of Millipore membranes were selected as control group to analyze and calculate the relationship between retention rate and MWCOs with exponential or logarithmic equation.A new and convenient method was provided for determining the membrane MWCO by modeling analysis retention rate with MWCOs,and the regression coefficients >*** feasibility and practicability of established method was verified by different manufactures' membrane and *** the detection progress,as the main ingredient of Panax notoginseng saponins,Notoginsenoside R_1,Ginsenoside Rg_1,Ginsenoside Rb_1 and Ginsenoside Rd with different surface activity,the MWCO range of UF membranes can be divided into two zones mainly due to the retention rate difference among Notoginsenoside R_1,Ginsenoside Rg_1,Ginsenoside Rb_1 and Ginsenoside *** 1,1000-10000;and Zone II,***,the new method would be helpful to improve the applicability of UF membrane in separation technology.

关键词： Ultrafiltration membrane Molecular weight cut-off

Thermal,Rheological and Mechanical Properties of Biodegradable Poly(propylene carbonate)/Epoxidized Soybean Oil Blends

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Chinese Journal of Polymer Science 2021年第12期39卷 1572-1580页

作者： ling Zhao Shi-ling Jia ze-peng Wang yun-Jing Chen Jun-Jia Bian li-Jing Han Hui-liang Zhang li-Song Dong Changchun UniversityofTechnology Changchun 130012China Key Laboratory of Polymer Ecomaterials Chinese Academy of SciencesChangchun Institute of Applied ChemistryChangchun 130022China Sinopec-SK(Wuhan)Petrochemical Company limited Wuhan 430000China

Biodegradable poly(propylene carbonate)(PPC)/epoxidized soybean oil(ESO)blends with different component ratios were prepared by melt blending to improve the performance of *** phase morphology,thermal properties,rheological properties and mechanical properties of the blends were in vestigated in *** exami nation revealed good in terfacial adhesi on betwee n PPC matrix and *** to DSC and DMA,as the content of ESO increased,the glass transition temperature of the PPC component increased,indicating that there was a strong in terfacial in teracti on between the PPC matrix and *** in terfacial in teraction may be caused by rin g-opening reaction between the hydroxyl end groups of PPC and the epoxy groups of ESO,which restricted the chain movement of PPC *** disappearanee of the epoxy groups in FTIR indicated that the in terfacial in teracti on betwee n the two phases was due to the rin g-openi ng reactio n betwee n PPC and *** the addition of ESO,the thermal stabilities were *** the increasing ESO content,the modulus gradually ***,the stre ngth at yield,the strength at break and the elon gation at break were in creased for the PPC/ESO blends,suggest!ng that the enhancement of the strength and toughness of PPC was achieved by the incorporation of *** rheological measurement revealed that the complex viscosity,storage modulus and loss modulus of PPC were in creased with the increasi ng ESO content at low freque ncy,which indicated that the addition of ESO enhanced the melt strength of PPC in stead of plasticizi ng PPC.

关键词： Poly(propylene carbonate) Epoxy soybean oil Compatibility Mechanical properties

Synthesis and Crystal Structure of a Novel Ternary Ni(II) Complex with 2-Hydroxyl-1,10- phenanthroline and 2-Hydroxynicotinic Acid as ligands

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Chinese Journal of Structural Chemistry 2006年第6期25卷 747-751页

作者： WANG Jian-Ge DU Qiao-yun li peng-yun Department of Chemistry Luoyang Normal University Luoyang 471022 China

A novel ternary complex of [NiL1L2·2H2O]·NO3·H2O （L1 = 2-hydroxyl-1,10-phenanthroline （HOphen）, L2 = 2-hydroxynicotinic acid （H2nicO）） was synthesized, and its crystal structure was determined by X-ray diffraction and further characterized by infrared and elementary analysis. The title complex （C18H18NiN4O10, Mr = 509.07） belongs to the triclinic system, space group P1^- with a = 712490（7）, b = 11.0164（10）, c = 13.3864（13）A, α = 91.6040（10）,β= 98.8620（10）, γ= 107.1140（10）°, V= 1006.43（17）A^3, Z = 2, Dc = 1.680 g/cm^3,μ= 1.032 mm^-1, F（000） = 524, the final R = 0.0461 and wR= 0.1238. In the complex, the Ni（H） ion is six-coordinated to assume a distorted octahedral geometry, and a 3D supramolecular network comes into being via weak intermolecular interactions of X-O--.H （X = N, O）.

关键词： 2-hydroxyl-1,10-phenanthroline 2-hydroxynicotinic acid nickel complex crystal structure

Research progress in the effects of terahertz waves on biomacromolecules

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Military Medical Research 2022年第1期9卷 63-70页

作者： liu Sun li Zhao Rui-yun peng Beijing Institute of Radiation Medicine Haidian District27 Taiping RoadBeijing 100850China

With the rapid development of terahertz technologies,basic research and applications of terahertz waves in biomedicine have attracted increasing *** rotation and vibrational energy levels of biomacromolecules fall in the energy range of terahertz waves;thus,terahertz waves might interact with ***,terahertz waves have been widely applied to explore features of the terahertz spectrum of ***,the effects of terahertz waves on biomacromolecules are largely *** some progress has been reported,there are still numerous technical barriers to clarifying the relation between terahertz waves and biomacromolecules and to realizing the accurate regulation of biological macromolecules by terahertz ***,further investigations should be conducted in the *** this paper,we reviewed terahertz waves and their biomedical research advantages,applications of terahertz waves on biomacromolecules and the effects of terahertz waves on *** findings will provide novel ideas and methods for the research and application of terahertz waves in the biomedical field.

关键词： Terahertz waves Biomacromolecules Effect Review

Factors influencing the pumpability of unclassified tailings slurry and its interval division

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International Journal of Minerals,Metallurgy and Materials 2019年第4期26卷 417-429页

作者： peng li yun-bing Hou Mei-feng Cai School of Civil and Resource Engineering University of Science and Technology Beijing Key Laboratory of High-Efficient Mining and Safety of Metal Mines (Ministry of Education of China) University of Science and Technology Beijing Beijing Key Laboratory of Urban Underground Space Engineering University of Science and Technology Beijing School of Resource and Safety Engineering China University of Mining and Technology (Beijing)

Tailings consolidation and discharging technology is currently a popular means for disposing tailings in China. In this study, we describe a laboratory investigation of the unclassified tailings slurry from an iron mine and analyze the influence of the concentration,amount of consolidation agent, and types of consolidation agent on the pumpability in terms of the slump, slump flow, and bleeding rate of the slurry. The results indicate that an increase in concentration leads to a pronounced decrease in the magnitude of the slump, slump flow,and the bleeding rate. Compared with the consolidation agents P.O42.5 and P.S.A32.5, the new consolidation agent offers substantial advantages in promoting the pumping performance of the slurry. The concentration more strongly affects the slump, slump flow, and the bleeding rate of the slurry than does the amount of the consolidation agent. We also constructed the pumpability interval of the slurry on the basis of the slump and bleeding rate and accordingly determined the proportioning parameters of the slurry with a concentration of 75 wt% to79 wt% and with a consolidation agent concentration of 2 wt%. In addition, we discussed the pumpability mechanism of the slurry.

关键词： tailings consolidation and discharging technology unclassified tailings new consolidation agent pumpability interval pumpability mechanism

UAVs cooperative task assignment and trajectory optimization with safety and time constraints

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Defence Technology（防务技术） 2023年第2期20卷 149-161页

作者： Duo Zheng yun-fei Zhang Fan li peng Cheng UAV Autonomous Control Institute Beijing Institute of TechnologyBeijing100081China Shanghai Institute of Mechanical and Electrical Engineering Shanghai201100China CASIC Research Institute of Intelligent Decision Engineering Wuhan100074China

This paper proposes new methods and strategies for Multi-UAVs cooperative attacks with safety and time constraints in a complex *** triangle is designed to construct a map of the complex flight environment for aerial ***-Map,Safe Flight Corridor(SFC),and Relative Safe Flight Corridor(RSFC)are applied to ensure each UAV flight trajectory's *** using such techniques,it is possible to avoid the collision with obstacles and collision between ***-curve is further developed to ensure that multi-UAVs can simultaneously reach the target at the specified time,and the trajectory is within the flight *** trajectory tracking controller is also designed based on model predictive control to track the planned trajectory *** simulation and experiment results are presented to verifying developed strategies of Multi-UAV cooperative attacks.

关键词： Multi-UAV Cooperative attacks Task assignment Trajectory optimization Safety constraints

5-羟甲基糠醛在CuPd(111)上的加氢反应机理研究

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原子与分子物理学报 2025年第4期42卷 53-57页

作者：张兴云周广丽石云山东临沂大学化学化工学院临沂276000

采用密度泛函理论,利用包含零点能校正的PBE-D3方法研究了5-羟甲基糠醛在双金属催化剂CuPd(111)上表面的加氢还原反应,考虑了两种反应路径,第一种反应路径是侧链上的醛基氧首先发生加氢反应生成F-CHOH中间体,然后F-CHOH中间体继续加氢生... 详细信息

采用密度泛函理论,利用包含零点能校正的PBE-D3方法研究了5-羟甲基糠醛在双金属催化剂CuPd(111)上表面的加氢还原反应,考虑了两种反应路径,第一种反应路径是侧链上的醛基氧首先发生加氢反应生成F-CHOH中间体,然后F-CHOH中间体继续加氢生成2,5-二羟甲基呋喃;第二种反应路径是侧链上的醛基碳先加氢原还原生成F-CH_(2)O中间体,生成的F-CH_(2)O进一步加氢还原生成2,5-二羟甲基呋喃.计算了两种竞争反应路径的活化能垒和反应热,结果表明,5-羟甲基糠醛在CuPd(111)面加氢还原生成2,5-二羟甲基呋喃的最佳反应路径为:F-CHO→F-CHOH→F-CH_(2)OH.

关键词： 5-羟甲基糠醛活化能垒反应热

维普期刊数据库博看期刊

Metabolic responses to combined water deficit and salt stress in maize primary roots

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Journal of Integrative Agriculture 2021年第1期20卷 109-119页

作者： li peng-cheng YANG Xiao-yi WANG Hou-miao PAN Ting YANG Ji-yuan WANG yun-yun XU Yang YANG ze-feng XU Chen-wu Jiangsu Key Laboratory of Crop Genetics and Physiology/Key Laboratory of Plant Functional Genomics Ministry of Education/Jiangsu Key Laboratory of Crop Genomics and Molecular Breeding/Agricultural CollegeYangzhou UniversityYangzhou 225009P.R.China Jiangsu Co-Innovation Center for Modern Production Technology o f Grain Crops Yangzhou UniversityYangzhou 225009P.R.China Joint International Research Laboratory of Agriculture and Agri-Product Safety of Ministry o f Education/Yangzhou University Yangzhou 225009P.R.China

Soil water deficit and salt stress are major limiting factors of plant growth and agricultural productivity. The primary root is the first organ to perceive the stress signals for drought and salt stress. In this study, maize plant subjected to drought, salt and combined stresses displayed a significantly reduced primary root length relative to the control plants. GC-MS was used to determine changes in the metabolites of the primary root of maize in response to salt, drought and combined stresses. A total of 86 metabolites were measured, including 29 amino acids and amines, 21 organic acids, four fatty acids, six phosphoric acids, 10 sugars, 10 polyols, and six others. Among these, 53 metabolites with a significant change under different stresses were identified in the primary root, and the content of most metabolites showed down-accumulation. A total of four and 18 metabolites showed significant up-and down-accumulation to all three treatments, respectively. The levels of several compatible solutes, including sugars and polyols, were increased to help maintain the osmotic balance. The levels of metabolites involved in the TCA cycle, including citric acid, ketoglutaric acid, fumaric acid, and malic acid, were reduced in the primary root. The contents of metabolites in the shikimate pathway, such as quinic acid and shikimic acid, were significantly decreased. This study reveals the complex metabolic responses of the primary root to combined drought and salt stresses and extends our understanding of the mechanisms involved in root responses to abiotic tolerance in maize.

关键词： maize primary root combination stress drought high salt stress metabolomics

Probing surface interactions of underwater oleophobic polyelectrolyte multilayers

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Petroleum Science 2021年第1期18卷 307-321页

作者： Kai li Wei Wang Zhi-peng Yu Hang Jin yun-Tong Ge Wei-Wei Gao Fan Xiao Hui-Rong Huang ze-Heng peng Jing Gong National Engineering Laboratory for Pipeline Safety MOE Key Laboratory of Petroleum EngineeringBeijing Key Laboratory of Urban Oil and Gas Distribution TechnologyChina University of PetroleumBeijing 102249China Key Laboratory of Environmental Protection Technology on Water Transport Tianjin Research Institute for Water Transport EngineeringTianjin 300456China

In the present work,the interaction mechanism of specific polyelectrolyte multilayers(PEMs),fabricated by layer-by-layer deposition of polydiallyldimethylammonium chloride(PDDA)and poly(sodium 4-styrenesulfonate)(PSS),is studied using atomic force *** underwater oil-repellency of PS S-capped PEMs was further explored by measuring the interaction forces between tetradecane droplets and PEMs-coated silica substrates under various *** force curves were analyzed following the Stokes-Reynolds-Young-Laplace theoretical *** consistency was achieved between the experimental and theoretical calculations at low NaCl concentrations(0.1 mM and 1 mM);however,underestimation of the attractive force was found as the NaCl concentration increases to moderate(10 mM)and high(100 mM)*** analyses and incorporated features toward a reduced surface charge density were considered based on the previous findings of the orientation of anionic benzenesulfonate moieties(liu et *** Angew Chem Int Ed 54(16):4851-4856,***://***/10.1002/anie.201411992).Short-range steric hindrance interactions were further introduced to simulate"brush"effect stemming from nanoscale surface *** is demonstrated in our work that the PSS-capped PEMs remains a stable underwater lipophobicity against high salinity,which renders it potential application in surface wetting modification and anti-fouling.

关键词： lipophobicity Salinity AFM Polyelectrolyte multilayers Surface roughness