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Loading capacity and emulsification phenomena of HREE extraction by dialkylphosphinic acids with different β,γ,δ-substituents

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Journal of Rare Earths 2024年第1期42卷 191-199,I0007页

作者： Junlian Wang Guodong xu wen xu Jianguo Cui Yufu Chen Ziyong Chang School of Civil and Resource Engineering University of Science and Technology BeijingBeijing100083China Key Laboratory of Ministry of Education for Efficient Mining and Safety of Metal Mines Beijing100083China State Key Laboratory of Baiyunobo Rare Earth Resource Researches and Comprehensive Utilization Baotou Research Institute of Rare EarthsBaotou014030China

The relationship between dialkylphosphinic acid structure and their loading capacity for HREEs and emulsification phenomena has rarely been studied.In this paper,we took Lu extraction as an example to study the effect of β,γ,δ-substituents of dialkylphosphinic acids on their loading capacity and anti-emulsification performance for HREEs.To discuss conveniently,the dialkylphosphinic acids were classified into two groups:β-substituent group(P208,INET-1,P218,USTB-1 and P227)and γ,δ-substituent group(P218,P2132 and Cyanex 272).For β-substituent group extractants,their loading capacities are in the order P208(299.7 mg/L)≈INET-1(299.5 mg/L)>P218(270.8 mg/L)>>USTB-1(163.1 mg/L)>P227(151.4 mg/L),while their anti-emulsification/gelation performances are just in the opposite order P227>USTB-1>P218>P208≈INET-1 under the studied conditions.For γ,δ-substituent group extractants,their loading capacities are in the order P218(270.8 mg/L)>P2132(192.3 mg/L)>Cyanex272(131.7 mg/L),while the anti-emulsification performance of P218 is better than those of P2132 and Cyanex 272.The loading capacity data given in the parentheses are obtained through repeatedly extracting Lu from ~4×10^(-4)mol/L of Lu aqueous feed solution with initial pH of 2.40 by 0.01 mol/L extractant at phase ratio A/O of 1:1.

关键词： Heavy rare earth element Dialkylphosphinic acid Extraction Loading capacity Emulsification

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Utility of real-time 3D visualization system in the early stage of phacoemulsification training

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International Journal of Ophthalmology(English edition) 2024年第3期17卷 577-582页

作者： Zhe xu Dan Chen Jing-Wei xu Yi-xuan Feng Ce Shi Li Zhang wen xu Eye Center the Second Affiliated HospitalSchool of MedicineZhejiang UniversityHangzhou 310009Zhejiang ProvinceChina Zhejiang Provincial Key Laboratory of Ophthalmology Hangzhou 310009Zhejiang ProvinceChina Zhejiang Provincial Clinical Research Center for Eye Diseases Hangzhou 310009Zhejiang ProvinceChina Zhejiang Provincial Engineering Institute on Eye Diseases Hangzhou 310009Zhejiang ProvinceChina

●AIM:To determine the teaching effects of a real-time three dimensional(3D)visualization system in the operating room for early-stage phacoemulsification training.●METHODS:A total of 10 ophthalmology residents of the first-year postgraduate were included.All the residents were novices to cataract surgery.Real-time cataract surgical observations were performed using a custom-built 3D visualization system.The training lasted 4wk(32h)in all.A modified International Council of Ophthalmology’s Ophthalmology Surgical Competency Assessment Rubric(ICO-OSCAR)containing 4 specific steps of cataract surgery was applied.The self-assessment(self)and expert-assessment(expert)were performed through the microsurgical attempts in the wet lab for each participant.●RESULTS:Compared with pre-training assessments(self 3.2±0.8,expert 2.5±0.6),the overall mean scores of posttraining(self 5.2±0.4,expert 4.7±0.6)were significantly improved after real-time observation training of 3D visualization system(P<0.05).Scores of 4 surgical items were significantly improved both self and expert assessment after training(P<0.05).●CONCLUSION:The 3D observation training provides novice ophthalmic residents with a better understanding of intraocular microsurgical techniques.It is a useful tool to improve teaching efficiency of surgical education.

关键词： 3D visualization system phacoemulsification training wet lab

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An index system for evaluation of agriculture green development at county level in China

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Frontiers of Agricultural Science and Engineering 2024年第1期11卷 55-68页

作者： Xiao xu Yanxiang JIA Yuan FENG Haixing ZHANG wen xu Qichao ZHU Beautiful Rural Construction Center Quzhou 324003China College of Resources and Environment China Agricultural UniversityBeijing 100193China National Academy of Agriculture Green Development China Agricultural UniversityBeijing 100193China

Agriculture green development(AGD)has become an unavoidable choice to address the unique national circumstances of China.This study established a county-level AGD evaluation index system,comprised three dimensions,food production,ecological environment and socioeconomic development,using 20 indicators.The assessment delved into historical trend and current situation,utilizing Spearman rank correlation analysis to analyze trade-off and synergy relationships,using Quzhou County,Hebei Province as a case study.The main findings were in four areas.Firstly,the index for AGD in Quzhou County increased by 58.9%from 1978 to 2019.The major contribution were the social economy(65.8%)and food production(53.5%),whereas the ecological environment was found to have had a negative impact.Secondly,in 2019,the AGD index was only 56.4,indicating substantial potential for improvement relative to the target value.A notable difference in scores existed between the three dimensions,with the order being ecological environment(66.3)>food production(61.7)>socioeconomic(41.3).Also,90%of the indicators did not reach the target value.Thirdly,relationship analysis of the indicators revealed that the synergistic effect exceeded the trade-off effect.Specifically,46.3%of the indicators had no significant relationship,35.3%had a synergistic relationship,and 18.4%had a trade-off relationship.Finally,interdimensional indicator relationships exhibited a trade-off effect between the ecological environment and both food production and socioeconomic dimensions.However,a positive trend of synergy between production and ecology has emerged since 2015.In conclusion,the quantitative evaluation index system exposed the unbalanced development and significant potential relative to the target value of AGD in Quzhou County,despite notable progress.

关键词： Agriculture green development index system quantitative evaluation Spearman correlation analysis

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Agriculture green development in China: insights and advances

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Frontiers of Agricultural Science and Engineering 2024年第1期11卷 5-19,I0005页

作者： Jianbo SHEN Qichao ZHU Yong HOU wen-Feng CONG wen xu Jiuliang xu Zhichao AN Xiaoqiang JIAO Kai ZHANG Tianxiang YU Lin MA Oene OENEMA William J.DAVIES Fusuo ZHANG State Key Laboratory of Nutrient Use and Management College of Resources and Environmental SciencesNational Academy of Agriculture Green DevelopmentChina Agricultural UniversityBeijing 100193China Key Laboratory of Agricultural Water Resources Center for Agricultural Resources ResearchInstitute of Genetic and Developmental BiologyChinese Academy of SciencesShijiazhuang 050021China Wageningen Environmental Research Wageningen University&ResearchWageningen6700 AAthe Netherlands Lancaster Environment Centre University of LancasterLancasterLA14YQUK

Reconciling the tasks of producing adequate amounts of nutritious food for the increasing global population while preserving the environment and natural ecosystems simultaneously is an enormous challenge. The concept of agriculture green development(AGD) and the necessary governmental policies were developed to address the aforementioned challenge in China and to help achieve the related global sustainable development goals. Agriculture green development emphasizes the synergy between green and development;current agriculture has to transform from the intensive farming with high inputs, high environmental impacts and low resource-use efficiency to a more sustainable agriculture, in order to ensure an adequate supply of nutritious food while delivering environmental integrity, improved economic profitability,and social equity. A research program on AGD was established by China Agricultural University with four research themes, namely: green crop production, green integrated crop-animal production, green food and industry,and green ecological environment and ecosystem services, to provide a scientific basis for future developments and to facilitate the implementation of AGD in practice. AGD requires a multistakeholder approach, fueled by innovative and interdisciplinary research. Joint actions have to be taken by governments, farmers, supply industries, consumers, educators, extension services and researchers to support AGD. This requires strong coordination and public awareness campaigns. This review presents the progress that has been made over the past 5 years and makes recommendations for more research and development, in order to better deliver agricultural green and sustainable development on national and international scales.

关键词： Agriculture ecosystem services environmental protection food security green development multi-sectoral cooperation sustainable development

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Optimizing nitrogen management in the food system for sustainable development: a case study of Quzhou County

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Frontiers of Agricultural Science and Engineering 2024年第1期11卷 113-121页

作者： Fanlei MENG Menru WANG Yong HOU Lin MA wenqi MA xuejun LIU Fusuo ZHANG wen xu College of Resources and Environmental Sciences National Academy of Agriculture Green DevelopmentState Key Laboratory of Nutrient Use and ManagementNational Observation and Research Station of Agriculture Green Development(QuzhouHebei)China Agricultural UniversityBeijing 100193China Water Systems and Global Change Group Wageningen University&Research6700 AA Wageningenthe Netherlands Environmental Systems Analysis Group Wageningen University&Research6708 PB Wageningenthe Netherlands Key Laboratory of Agricultural Water Resources Hebei Key Laboratory of Soil EcologyCenter for Agricultural Resources ResearchInstitute of Genetic and Developmental BiologyChinese Academy of SciencesShijiazhuang 050021China College of Resources and Environment Science Hebei Agricultural UniversityBaoding 071001China

Nitrogen(N) is an essential nutrient for food production. The rapid increase in population requires high inputs of N to meet the growing food demand. If not managed well, the substantial loss of N from the food system has multiple impacts on grain yield, air and water pollution, and the economic benefits of agricultural. Multi-objective(food security, environmental sustainability and economic sustainability) synergistic consideration of N management in the food system is still lacking. This study employed strategies for optimizing N management in the food system, using Quzhou County as a typical example on the North China Plain. Firstly, a food chain approach was adopted to understand drivers and reasons behind N losses from the food system.Secondly, a top-down approach was used to define multi-objective N management, taking into consideration food security, environmental sustainability and economic sustainability. Multi-objective N management aims to reduce N losses to the environment and increase N use efficiencies,while simultaneously increasing yields and economic benefits. Thirdly, 3R(reduce-retain-recycle) N management strategies were identified for specific crops and animals through a bottom-up approach and then analyzed the potential of these strategies to achieve the multi-objectives. Finally, there is a discussion of how to engage different stakeholders to promote the technologies implementation. This study provides new insights into the synergistic achievement of multi-objective N management in the food system and the development of environmentally-friendly agriculture.

关键词： Agriculture green development food system multi-objective nitrogen management

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Keemun black tea stems and leaves: Comparison of chemical characterization and anti-inflammatory activities

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Food Science and Human Wellness 2024年

作者： Mengting Zhu Xiaoqing Rong Mingchun wen Piaopiao Long Zongde Jiang wen xu Daniel Granato Liang Zhang State Key Laboratory of Tea Plant Biology and Utilization Anhui Agricultural University Key Laboratory of Quality Evaluation of Chinese Medicine of the Guangdong Provincial Medical Products Administration the Second Clinical College Guangzhou University of Chinese Medicine International Joint Laboratory on Tea Chemistry and Health Effects of Ministry of Education Anhui Agricultural University Bioactivity & Applications Lab Department of Biological Sciences Faculty of Science and Engineering University of Limerick

This work aims to compare the chemical composition and anti-inflammatory effects on RAW264.7 macrophages of Keemun black tea stems and leaves. Fifty volatile compounds were identified in tea stems and leaves， and aldehydes， alcohols， and esters were the main volatile compound categories. Eleven key volatile compounds， including geraniol， phenylacetaldehyde， methyl salicylate， linalool， etc. contributed to distinguishing the tea stems from the tea leaves. In the quantitative and LC-MS-based metabolomics analysis， higher contents of amino acids， monosaccharides， and quinic acid were found in stems than in leaves. Inversely， higher contents of tea pigments， flavan-3-ols， gallic acid， purine alkaloids， and flavonol glycosides were present in tea leaves than in stems. LC-MS-based metabolomics also revealed that organic acids were the most critical non-volatile compounds responsible for the differences between tea stems and leaves. Furthermore， tea stems had better inhibiting effects of pro-inflammatory cytokines (IL-1β and IL-6) in lipopolysaccharide-challenged RAW264.7 macrophages than tea leaves， while no significant differences exist between leaves and stems for inhibiting the secretion of TNF-α and NO. In conclusion， our results support using Keemun black tea stems as a novel source of anti-inflammatory compounds.

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A combined computational/experimental study of anode-concerned voltage drop in aqueous primary Mg-air batteries

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Journal of Magnesium and Alloys 2024年第5期12卷 1854-1866页

作者： wen xu Min Deng Darya Snihirova Linqian Wang Yulong Wu Sviatlana V.Lamaka Mikhail L.Zheludkevich Daniel H?che Institute of Surface Science Helmholtz-Zentrum Hereon School of Materials Science and Engineering Hebei University of Technology Institute for Materials Science Faculty of Engineering Kiel University

The voltage drop appearing at Mg anode-electrolyte interface is a critical issue for the battery power and energy density of aqueous primary Mg-air batteries. The respective voltage loss is typically assigned to the deposits layer forming on the anode surface during discharge. In this work, we experimentally and computationally investigate the critical factors affecting the voltage drop at Mg anode towards a deeper understanding of the contribution of deposit and its growth. A two-dimensional(2D) mathematical model is proposed to compute the voltage drop of Mg-0.15Ca wt.% alloy(Mg-0.15Ca) by means of a semi-empirical formulas and experiments-based modification model, considering the effect of discharge current density, the negative difference effect(NDE) and surface deposits layer itself. This model is utilized to simulate the discharge potential of the anode at predefined experimental current densities. The computed voltage drop(half-cell voltage) is in good agreement with the experimental value. The applicability of the mathematical model is successfully validated on the second material(namely high-purity Mg).

关键词： Aqueous Mg-air battery Voltage drop NDE Charge transfer Deposits-related resistances

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Plasma Metabonomics of Human Adenovirus-infected Patients with Pneumonia and Upper Respiratory Tract Infection

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Current Medical Science 2024年第1期44卷 121-133页

作者： Ting-ting WEI wen xu Bo TU Wan-xue ZHANG Xin-xin YANG Yiguo ZHOU Shan-shan ZHANG Jun-lian YANG Ming-zhu XIE Juan DU Wei-wei CHEN Qing-bin LU Department of Epidemiology and Biostatistics School of Public HealthPeking UniversityBeijing 100191China Department of Infectious Disease The Fifth Medical Center of Chinese PLA General HospitalNational Clinical Research Center for Infectious DiseasesBeijing 100039China Department of Laboratorial Science and Technology&Vaccine Research Center School of Public HealthPeking UniversityBeijing 100191China Department of Health Policy and Management School of Public HealthPeking UniversityBeijing 100191China Global Center for Infectious Disease and Policy Research&Global Health and Infectious Diseases Group Peking UniversityBeijing 100191China Key Laboratory of Epidemiology of Major Diseases(Peking University) Ministry of EducationBeijing 100191China

Objective Human adenovirus(HAdV)infection is common and can develop to serious conditions with high mortality,yet the mechanism of HAdV infection remains unclear.In the present study,the serum metabolite profiles of HAdV-7-infected patients with pneumonia or upper respiratory tract infection(URTI)were explored.Methods In total,35 patients were enrolled in the study following an outbreak of HAdV-7 in the army,of whom 14 had pneumonia and 21 had URTI.Blood samples were collected at the acute stage and at the recovery stage and were analyzed by untargeted metabolomics.Results Over 90% of the differential metabolites identified between the pneumonia patients and URTI patients were lipids and lipid-like molecules,including glycerophospholipids,fatty acyls,and sphingolipids.The metabolic pathways that were significantly enriched were primarily the lipid metabolism pathways,including sphingolipid metabolism,glycerophospholipid metabolism,and linoleic acid metabolism.The sphingolipid metabolism was identified as a significantly differential pathway between the pneumonia patients and URTI patients and between the acute and recovery stages for the pneumonia patients,but not between the acute and recovery stages for the URTI patients.Ceramide and lactosylceramide,involved in sphingolipid metabolism,were significantly higher in the pneumonia patients than in the URTI patients with good discrimination abilities[area under curve(AUC)0.742 and 0.716,respectively;combination AUC 0.801].Conclusion Our results suggested that HAdV modulated lipid metabolism for both the patients with URTI and pneumonia,especially the sphingolipid metabolism involving ceramide and lactosylceramide,which might thus be a potential intervention target in the treatment of HAdV infection.

关键词： human adenovirus metabonomic lipids pneumonia upper respiratory tract infection

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Advances in Research of Anti-tumor Effect of Aconiti Radix

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Medicinal Plant 2024年第2期15卷 80-83页

作者： Jing GAO Fanbo JING Lifang FENG wen xu Changkai ZHOU The Third People s Hospital of Qingdao Qingdao 266041China The Affiliated Hospital of Qingdao University Qingdao 266100China

In this paper,the anti-tumor effects of Aconiti Radix were reviewed and summarized,and the clinical feasibility of Aconiti Radix as a potential anti-tumor drug was analyzed,in order to provide a useful reference for t... 详细信息

关键词： Aconiti Radix Anti-tumor Research advances Feasibility analysis

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Nonlinear Extrapolation Estimates of π

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Acta Mathematicae Applicatae Sinica 2024年第1期40卷 91-108页

作者： wen-qing xu Sha-sha Wang Da-chuan xu Beijing Institute for Scientific and Engineering Computing Beijing University of TechnologyBeijing100124China Department of Mathematics and Statistics California State UniversityLong BeachCalifornia90840USA Department of Mathematics and Physics Shijiazhuang Tiedao UniversityShijiazhuang050043China

The classical Archimedean approximation of π uses the semiperimeter or area of regular polygons inscribed in or circumscribed about a unit circle in R~2 and it is well-known that by using linear combinations of these basic estimates,modern extrapolation techniques can greatly speed up the approximation process.Similarly,when n vertices are randomly selected on the circle,the semiperimeter and area of the corresponding random inscribed and circumscribing polygons are known to converge to π almost surely as n→∞,and by further applying extrapolation processes,faster convergence rates can also be achieved through similar linear combinations of the semiperimeter and area of these random polygons.In this paper,we further develop nonlinear extrapolation methods for approximating π through certain nonlinear functions of the semiperimeter and area of such polygons.We focus on two types of extrapolation estimates of the forms χ_n=S_n~αA_n~β and Y_n(p)=(αS_n~p+βA_n~p)~(1/p) where α+β=1,p≠0,and Sn and An respectively represents the semiperimeter and area of a random n-gon inscribed in the unit circle in R~2,and Xn may be viewed as the limit of Y_n(p) when p→0.By deriving probabilistic asymptotic expansions with carefully controlled error estimates for Xn and Y_n(p),we show that the choice α=4/3,β=-1/3 minimizes the approximation error in both cases,and their distributions are also asymptotically normal.

关键词： Archimedean polygons random polygons approximations ofπ extrapolation processes asymptotic convergence

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