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Protecting Cell Walls from Binding Aluminum by Organic Acids Contributes to Aluminum Resistance

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Journal of Integrative Plant Biology 2009年第6期51卷 574-580页

作者： Ya-Ying li yue-Jiao Zhang yuan Zhou Jian-li Yang Shao-Jian Zheng Ministry of Agriculture Key Laboratory for Non-Point Pollution Control Zhejiang University Hangzhou 310029 China State Key Laboratory of Plant Physiology and Biochemistry College of Life Sciences Zhejiang University Hangzhou 310058 China

Aluminum-induced secretion of organic acids from the root apex has been demonstrated to be one major AI resistance mechanism in plants. However, whether the organic acid concentration is high enough to detoxify AI in the growth medium is frequently questioned. The genotypes of AI-resistant wheat, Cassia tora L. and buckwheat secrete malate, citrate and oxalate, respectively. In the present study we found that at a 35% inhibition of root elongation, the AI activities in the solution were 10, 20, and 50 μM with the corresponding malate, citrate, and oxalate exudation at the rates of 15, 20 and 21 nmol/cm2 per 12 h, respectively, for the above three plant species. When exogenous organic acids were added to ameliorate AI toxicity, twofold and eightfold higher oxalate and malate concentrations were required to produce the equal effect by citrate. After the root apical cell walls were isolated and preincubated in 1 mM malate, oxalate or citrate solution overnight, the total amount of AI adsorbed to the cell walls all decreased significantly to a similar level, implying that these organic acids own an equal ability to protect the cell walls from binding AI. These findings suggest that protection of cell walls from binding AI by organic acids may contribute significantly to AI resistance.

关键词： adsorption and desorption aluminum toxicity cell wall chelation detoxification organic acid.

Recursive super-convergence computation for multi-dimensional problems via one-dimensional element energy pro jection technique

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Applied Mathematics and Mechanics(English Edition) 2018年第7期39卷 1031-1044页

作者： Si yuan yue WU Qinyan XING Key Laboratory of Civil Engineering Safety and Durability of China Education Ministry Department of Civil Engineering Tsinghua University

This paper presents a strategy for computation of super-convergent solutions of multi-dimensional problems in the finite element method （FEM） by recursive application of the one-dimensional （1D） element energy projection （EEP） technique. The main idea is to conceptually treat multi-dimensional problems as generalized 1D problems, based on which the concepts of generalized 1D FEM and its consequent EEP formulae have been developed in a unified manner. Equipped with these concepts, multi-dimensional problems can be recursively discretized in one dimension at each step, until a fully discretized standard finite element （FE） model is reached. This conceptual dimension-by- dimension （D-by-D） discretization procedure is entirely equivalent to a full FE discretization. As a reverse D-by-D recovery procedure, by using the unified EEP formulae together with proper extraction of the generalized nodal solutions, super-convergent displacements and first derivatives for two-dimensional （2D） and three-dimensional （3D） problems can be obtained over the domain. Numerical examples of 3D Poisson＇s equation and elasticity problem are given to verify the feasibility and effectiveness of the proposed strategy.

关键词： three-dimensional(3D)problem generalized one-dimensional(1D)finiteelement method (FEM) dimension-by-dimension(D-by-D) super-convergence elementenergy projection(EEP)

^(99m)Tc-右旋糖酐105淋巴显像剂质量研究及临床应用

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新药与临床 1992年第2期11卷 95-98页

作者：陆伟跃马远鸣李明刘永昌何广仁上海医科大学药学院上海200032 上海医科大学附属华山医院上海200040 苏州医学院附属第二医院苏州215000

本文通过^(99m)Tc-右旋糖酐105放化纯及在家兔淋巴系统定向试验,评价质量;通过临床使用,验证其实用性。本制剂放化纯显著高于95％,放置时间、温度对其无显著影响;^(99m)Tc-右旋糖酐105明显定向于家兔淋巴系统,腘淋巴结与各脏器摄取量之... 详细信息

本文通过^(99m)Tc-右旋糖酐105放化纯及在家兔淋巴系统定向试验,评价质量;通过临床使用,验证其实用性。本制剂放化纯显著高于95％,放置时间、温度对其无显著影响;^(99m)Tc-右旋糖酐105明显定向于家兔淋巴系统,腘淋巴结与各脏器摄取量之比均大于180倍;29例病人淋巴系统显影异常率为96％,6例病人淋巴结活检结果与显影图像完全吻合。

关键词：右旋糖酐淋巴造影术放射性核素

基于UTXO模型区块链的众包物流可信身份认证模型

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江苏大学学报（自然科学版） 2025年第1期46卷 57-63页

作者：李致远吴越张威威李沅格江苏大学计算机科学与通信工程学院江苏镇江212013 江苏大学江苏省工业网络安全技术重点实验室江苏镇江212013 江苏大学江苏省泛在数据智能感知与分析应用工程研究中心江苏镇江212013

针对现有集中式众包物流平台中用户身份数据存储与管理存在的隐私泄露和篡改问题,提出一种基于UTXO模型区块链的众包物流可信身份认证模型.该模型包括利用区块链技术实现身份注册、身份验证、身份撤销及身份认证.针对链上存储用户隐私... 详细信息

针对现有集中式众包物流平台中用户身份数据存储与管理存在的隐私泄露和篡改问题,提出一种基于UTXO模型区块链的众包物流可信身份认证模型.该模型包括利用区块链技术实现身份注册、身份验证、身份撤销及身份认证.针对链上存储用户隐私数据风险的问题,采用混合加解密方案对链上个人信息做安全存储与分享;针对平台认证用户身份的问题,采用可信身份凭证以零知识证明方式登录众包物流平台.对身份信息以及认证进行安全性分析,并将该方法与liU方法、li方法的安全性能进行了对比.在Python3.9环境下完成试验,进行了身份信息加密和零知识身份认证测试分析.结果表明该方案的认证时延和处理事务能力均优于现有的SHAO方案.

关键词：众包物流区块链身份管理 UTXO模型可信身份认证零知识证明

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Journal of Hydrodynamics 2021年第4期33卷 782-786页

作者： Jiang-hua li Yu-xian Xia Xiang Qiu yue-hong Qian Jia-hua li yuan Fu Shanghai Institute of Applied Mathematics and Mechanics School of Mechanics and Engineering ScienceShanghai UniversityShanghai200072China School of Mechanical Engineering Shanghai Institute of TechnologyShanghai201418China School of Science Shanghai Institute of TechnologyShanghai201418China School of Mathematical Sciences Soochow UniversitySuzhou215006China College of Urban Construction and Safety Engineering Shanghai Institute of TechnologyShanghai201418China

In this paper, liutex similarity is extended and revised in channel turbulence. liutex similarity is free from viscous dissipation, relaxing the very high Reynolds number assumption of K41. liutex similarity hypothesis in 2-D channel turbulence is first proposed and estimated, which denotes that the statistical properties of liutex field are uniquely and universally determined by the scale l, liutex vortex number density n(A) with each area A and mean dissipation rate of square of liutex magnitude ηL. The liutex spectrum is EL (k) ∼ C[n(A)1/2ηL]1/3k−5/3 in the inertial range where energy spectrum exhibits double cascades. The scaling behaviors of liutex spectrum in 2-D are independent of Reynolds number. liutex structure functions are defined as liutexp (l) ≡ 〈[δR∥(l)]p〉 which are in dependent of scales. It is found that liutexp (l) ∼ C′(ηL)p/3l0 by dimensional analysis.

关键词： liutex similarity energy spectrum 2-D turbulence

The origin and evolution of Earth's nitrogen

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National Science Review 2024年第6期11卷 56-75页

作者： yuan li State Key Laboratory of Isotope Geochemistry Guangzhou Institute of GeochemistryChinese Academy of Sciences Bayerisches Geoinstitut Universit?t Bayreuth

Nitrogen is a vital element for life on Earth. Its cycling between the surface(atmosphere + crust) and the mantle has a profound influence on the atmosphere and climate. However, our understanding of the origin and evolution of Earth's nitrogen is still incomplete. This review presents an overview of the current understanding of Earth's nitrogen budget and the isotope composition of different reservoirs, laboratory constraints on deep nitrogen geochemistry, and our understanding of the origin of Earth's nitrogen and the deep nitrogen cycle through plate subduction and volcanism. The Earth may have acquired its nitrogen heterogeneously during the main accretion phase, initially from reduced, enstatite-chondrite-like impactors,and subsequently from increasingly oxidized impactors and minimal CI-chondrite-like materials. like Earth's surface, the mantle and core are also significant nitrogen reservoirs. The nitrogen abundance and isotope composition of these three reservoirs may have been fundamentally established during the main accretion phase and have been insignificantly modified afterwards by the deep nitrogen cycle, although there is a net nitrogen ingassing into Earth's mantle in modern subduction zones. However, it is estimated that the early atmosphere of Earth may have contained ～1.4 times the present-day atmospheric nitrogen(PAN),with ～0.4 PAN being sequestered into the crust via biotic nitrogen fixation. In order to gain a better understanding of the origin and evolution of Earth's nitrogen, directions for future research are suggested.

关键词： nitrogen isotopes silicate Earth atmosphere magma ocean

Synthesis and biological evaluation of new pyrrolopyrazinone compounds as potential antitumor agents

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Chinese Chemical Letters 2013年第7期24卷 619-621页

作者： Ying Meng Guan Wang yue li Kuan Hou yue yuan li-Juan Zhang Hong-Rui Song Wei Shi Key Laboratory of Structure-Based Drug Design and Discovery Ministry of EducationShenyang Pharmaceutical University Key Laboratory for Molecular Enzymology and Engineering Ministry of EducationJilin University Key Laboratory for Molecular Enzymology and Engineering.Ministry of Education Jilin University

A series of pyrrolo[1,2-a]pyrazinone compounds （Sa-gf） were synthesized, and their cytotoxic activity against SKOV-3, A549, HeLa cells in vitro were evaluated by the MTF method. Some of the compounds showed potential antitumor activity against three tumor cell lines. Among them, compounds 9c and 9d showed the most potent cytotoxic activity. The preliminary mechanism of action was discussed.

关键词： Pyrrolopyrazinone Antitumor Synthesis

Pre-treatment of pyridine wastewater by new cathodic–anodic-electrolysis packing

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Journal of Environmental Sciences 2018年第1期30卷 43-49页

作者： Yang Jin Qinyan yue Kunlun Yang Suqing Wu Shengjie li Baoyu Gao yuan Gao Shandong University Jinan 250100China

A novel cathodic–anodic-electrolysis packing（CAEP） used in the treatment of pyridine wastewater was researched, which mainly consisted of 4,4′-diamino-2,2′-disulfonic acid（DSD acid） industrial iron sludge. The physical properties and morphology of the packing were studied. The CAEP was used in a column reactor during the pretreatment of pyridine wastewater. The influence of p H, hydraulic retention time（HRT）, the air–liquid ratio（A/L）and the initial concentration of pyridine were investigated by measuring the removal of total organic carbon（TOC） and pyridine. The characterization results showed that the bulk density, grain density, water absorption percentage and specific surface area were 921 kg/m3,1086 kg/m3, 25% and 29.89 m^2/g, respectively; the removal of TOC and pyridine could reach50% and 58% at the optimal experimental conditions（p H = 3, HRT = 8 hr, A/L = 2）. Notably,the surface of the packing was renewed constantly during the running of the filter, and the handling capacity was stable after running for three months.

关键词： Cathodic-anodic-electrolysis packing Pyridine wastewater pH Hydraulic retention time Air-liquid ratio Initial concentration

Coalbed Methane Enrichment Regularity and Major Control Factors in the Xishanyao Formation in the Western Part of the Southern Junggar Basin

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Acta Geologica Sinica(English Edition) 2020年第2期94卷 485-500页

作者： yuan yuan SHAN Yansheng TANG yue CAO Daiyong China University of Mining&Technology Beijing 100083China China Geological Survey Oil and Gas SurveyBeijing 100083China

There are abundant coal and coalbed methane(CBM)resources in the Xishanyao Formation in the western region of the southern Junggar Basin,and the prospects for CBM exploration and development are *** promote the exploration and development of the CBM resources of the Xishanyao Formation in this area,we studied previous coalfield survey data and CBM geological exploration ***,we analyzed the relationships between the gas content and methane concentration *** seam thickness,burial depth,coal reservoir physical characteristics,hydrogeological conditions,and roof and floor *** addition,we briefly discuss the main factors influencing CBM ***,we found that the coal strata of the Xishanyao Formation in the study area are relatively simple in structure,and the coal seam has a large thickness and burial depth,as well as moderately good roof and floor *** hydrogeological conditions and coal reservoir physical characteristics are also conducive to the enrichment and a high yield of *** believe that the preservation of CBM resources in the study area is mainly controlled by the structure,burial depth,and hydrogeological ***,on the basis of the above results,the coal seam of the Xishanyao Formation in the synclinal shaft and buried at depths of 700-1000 m should be the first considered for development.

关键词： coalbed methane enrichment regularity major control factors Xishanyao Formation western area of the southern Junggar Basin