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秸秆还田对黑土中磷素吸附特性及释放风险研究

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中国环境科学 2024年第8期44卷 4475-4483页

作者：温芳悦张羽陈尚才王玉军吉林农业大学资源与环境学院吉林长春130118 吉林省征地事务中心吉林长春130061 内蒙古牙克石市乡村振兴促进中心内蒙古牙克石022150

通过分析秸秆离田免耕(MG)、秸秆覆盖还田(FG)、秸秆深翻还田(SF)对土壤理化性质及土壤磷素的吸附特性的影响,研究由于土壤理化性质的改变对于磷吸附特性的影响,并进一步分析磷素在土壤中的释放风险.结果表明,秸秆还田后,土壤有机质、... 详细信息

通过分析秸秆离田免耕(MG)、秸秆覆盖还田(FG)、秸秆深翻还田(SF)对土壤理化性质及土壤磷素的吸附特性的影响,研究由于土壤理化性质的改变对于磷吸附特性的影响,并进一步分析磷素在土壤中的释放风险.结果表明,秸秆还田后,土壤有机质、有效磷含量增大,土壤容重降低.与秸秆离田免耕相比,秸秆覆盖还田后土壤磷的吸附量减少20.1%,秸秆深翻还田后的土壤磷的吸附量减少35.0%.3种不同耕作模式下黑土中DPS(磷饱和度)分别为MG:0.3%,FG:4.0%,SF:10.2%,PSI(磷吸持指数)分别为MG:41.14,FG:40.04,SF:36.09(mg P/(100g))/(μmol/L),ERI(磷释放风险指数)分别为MG:0.7%,FG:9.9%,SF:28.3%.综上所述,秸秆覆盖还田及秸秆深翻还田均可显著增加土壤有机质,降低土壤对磷的吸附能力,提高土壤磷的有效性,但同时也提高了土壤磷吸附饱和度,易引起磷素流失的风险.

关键词：黑土秸秆还田磷吸附释放风险

颅内-颅内血管搭桥术治疗九例复杂颅内动脉瘤疗效分析

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中国现代神经疾病杂志 2024年第8期24卷 651-656页

作者：周杨宗黄正李梦君王君宇陈风华中南大学湘雅医院神经外科中南大学脑血管病研究中心长沙410008

目的探讨颅内-颅内血管搭桥术治疗复杂颅内动脉瘤的疗效。方法纳入2014年2月至2020年5月在中南大学湘雅医院行颅内-颅内血管搭桥术的9例复杂颅内动脉瘤患者,采用桥血管移植搭桥或传出动脉(受体动脉)再植术。术后行CTA或DSA检查桥血管... 详细信息

目的探讨颅内-颅内血管搭桥术治疗复杂颅内动脉瘤的疗效。方法纳入2014年2月至2020年5月在中南大学湘雅医院行颅内-颅内血管搭桥术的9例复杂颅内动脉瘤患者,采用桥血管移植搭桥或传出动脉(受体动脉)再植术。术后行CTA或DSA检查桥血管通畅情况、动脉瘤夹闭或切除情况、随访期间检查动脉瘤新发情况;并于出院时及随访期间采用改良Rankin量表(mRS)评估神经功能预后。结果采用桡动脉(RA)或大隐静脉(GSV)移植桥血管4例,传出动脉(受体动脉)再植术5例,分别为大脑中动脉M2-RA-M2搭桥术1例、大脑前动脉A3-GSV-A3搭桥术1例、大脑后动脉P2-RA-P2搭桥术1例、颈内动脉(ICA)海绵窦段-GSV-ICA搭桥术1例、大脑中动脉M2下干-M2上干搭桥术1例、大脑前动脉A3-对侧A3搭桥术2例、小脑后下动脉-小脑前下动脉搭桥术2例。术后3 d复查CTA均显示桥血管通畅,未见动脉瘤显影;出院后3个月2例失访,余7例复查CTA或DSA均显示桥血管通畅,无动脉瘤新发;此7例患者长期随访,随访时间30.71个月,mRS评分均≤1分。结论颅内-颅内血管搭桥术适用于常规手术难以处理的复杂颅内动脉瘤等疾病,具有所需桥血管短、更符合生理状态血流动力学等优势。

关键词：颅内动脉瘤脑血管重建术桡动脉隐静脉

3种咬合纸在人工种植牙修复中的应用效果比较

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中国口腔颌面外科杂志 2024年第1期22卷 63-67页

作者：潘旭祯王煜君舟山市口腔医院城西门诊部浙江舟山316000

目的 :比较3种咬合纸在人工种植牙修复中的应用效果。方法 :选取2020年2月—2022年2月舟山市口腔医院117例人工种植牙修复患者,根据咬合紧密程度分为A、B、C 3组,每组39例,均为单颗患牙。A组采用12μm咬合纸,B组采用20μm咬合纸,C组采... 详细信息

目的 :比较3种咬合纸在人工种植牙修复中的应用效果。方法 :选取2020年2月—2022年2月舟山市口腔医院117例人工种植牙修复患者,根据咬合紧密程度分为A、B、C 3组,每组39例,均为单颗患牙。A组采用12μm咬合纸,B组采用20μm咬合纸,C组采用30μm咬合纸。比较3组修复后3个月的牙周指标(种植体周骨吸收程度、种植体周围探诊深度、牙龈指数、牙松动度),修复前、修复当天、修复后3个月和修复后6个月咬合平衡指数绝对值,并评估患者及医师满意度。采用SPSS 22.0软件包对数据进行统计学分析。结果:3组牙周指标比较无统计学差异(P>0.05);3组组内咬合平衡指数绝对值比较,修复后6个月<修复后3个月<修复当天<修复前(P<0.05);修复后3个月,A组咬合平衡指数绝对值显著小于B组和C组(P<0.05);A组患者及医师满意度显著高于B组和C组(P<0.05)。结论:与20μm、30μm咬合纸比较,12μm咬合纸应用于人工种植牙修复能调整咬合平衡,提高患者及医师满意度。

关键词：咬合纸种植牙修复种植体周骨吸收程度咬合平衡指数

Theoretical Chemistry Study of the Hydrogen-bonded Interaction between Acylamine and Chloromethane Compounds

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Chinese Journal of Structural Chemistry 2005年第12期24卷 1416-1424页

作者： GE Qing-yu wang Hai-jun CHEN Jian-Hua School of Chemical and Material Engineering Southern Yangtze University Wuxi 214036 China

The hydrogen-bonded interaction between acylamine and chloromethane was studied using theoretical calculation methods. Looking the interaction system as a hydrogen-bonded complex, the geometric optimization of the interaction system was performed with HF and B3LYP methods at 6-311＋＋G^＊＊ level. Stable structures of these complexes were obtained. Binding energies and some other physical chemistry parameters of them were computed and compared. According to the calculation results, it can be identified that DMA （DMF or DEF） can form stable complex with chloromethane by the hydrogen-bonded interaction between them. The stable orders of these hydrogen-bonded complexes were obtained and described as： DMF-CHCl3〉DMF-CH2Cl2〉 DMF-CH3Cl, DEF-CHCl3 〉 DEF-CH2Cl2 〉 DEF-CH3Cl, DMA-CHCl3 〉 DMA-CH2Cl2 〉 DMA-CH3Cl, respectively.

关键词： theoretical calculation acylamine chloromethane (CHnCl4-n n = 0~4) binding energy.

Free cupric ions in contaminated agricultural soils around a copper mine in eastern Nanjing City, China

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Journal of Environmental Sciences 2006年第5期18卷 927-931页

作者： LUO Xiao-san ZHOU Dong-mei wang yu-jun State Key Laboratory of Soil and Sustainable Agriculture Institute of Soil Science Chinese Academy of Sciences Nanjing 210008 China Graduate School of the Chinese Academy of Sciences Beijing 100039 China

To determine the environmental free metal ion activity was a recent hot issue. A method to measure low-level free cupric ion activity in soil solution extracted with 0.01 mol/L KNO3 was developed by using cupric ion-selective electrode （ISE） and calibrating with Cu-buffer solution. Three copper buffers including iminodiacetic acid （IDA）, ethylenediamine （EN）, and glycine （Gly） were compared for calibrating the Cu-ISE curves in the range of free cupric ions （pCu^2＋） 7-13. The Cu-EN buffer showed the best electrode response and thus was applied as the calibration buffer. The pCu^2＋ of 39 contaminated agricultural soils around a copper mine was measured, ranging from 5.03 to 9.20. Most Cu in the soil solutions was found to be complexed with dissolved soil organic matters, averaging 98.1%. The proportion of free Cu^2＋ ions in the soil solutions decreased with the increasing of solution pH. Soluble Cu and free Cu^2＋ ions concentrations were analyzed by multiple linear regressions to evaluate the effects of soil properties on metal levels and speciation. The results showed that soil solution pH was the most significant factor influencing pCu^2＋（with R^2 value of 0.76）, while not important for the soluble Cu concentration.

关键词： copper ion selective electrode (Cu-ISE) free metal ion activity soil solution metal speciation bioavailability

Effects of phosphate on the adsorption of glyphosate on three different types of Chinese soils

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Journal of Environmental Sciences 2005年第5期17卷 711-715页

作者： wang yu-jun ZHOU Dong-mei SUN Rui-juan State Key Laboraton of Soil and Sustainable Agriculture Institute of Soil Science Chinese Academy of Sciences Nanjing 210008 China Graduate School of Chinese Academy of Sciences Beijing 100039 China

Glyphosate （GPS） is a non-selective, post-mergence herbicide that is widely used throughout the world. Due to the similar molecular structures of glyphosate and phosphate, adsorption of glyphosate on soil is easily affected by coexisting phosphate, especially when phosphate is applied at a significant rate in farmland. This paper studied the effects of phosphate on the adsorption of glyphosate on three different types of Chinese soils including two variable charge soils and one permanent charge soil. The results indicated that Freundlich equations used to simulate glyphosate adsorption isotherms gave high correlation coefficients（0.990-0.998） with K values of 2751, 2451 and 166 for the zhuanhong soil（ZH soil, Laterite）, red soil（ RS, Udic Ferrisol） and Wushan paddy soil（WS soil, Anthrosol）, respectively. The more the soil iron and aluminum oxides and clay contained, the more glyphosate adsorbed. The presence of phosphate significantly decreased the adsorption of glyphosate to the soils by competing with glyphosate for adsorption sites of soils. Meanwhile, the effects of phosphate on adsorption of glyphosate on the two variable charge soils were more significant than that on the permanent charge soil. When phosphate and glyphosate were added in the soils in different orders, the adsorption quantities of glyphosate on the soils were different, which followed GPS-soil 〉 GPS-P-soil = GPS-Soil-P 〉 P-soil-GPS, meaning a complex interaction occurred among glyphosate, phosphate and the soils.

关键词： soil glyphosate phosphate competitive adsorption

加强和改进高职院校学生党支部学生党员教育管理研究

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湖北开放职业学院学报 2024年第8期37卷 131-133页

作者：王玉军张思源北京财贸职业学院北京101101

高职院校学生党员是实现伟大中国梦的重要力量之一,是一支重要的党的储备力量,它的发展壮大为党输入新鲜血液。新时代赋予学生党员新的历史使命。高质量党员教育管理是时代的要求,更是高校实现立德树人目标的重要抓手。目前,高职院校学... 详细信息

高职院校学生党员是实现伟大中国梦的重要力量之一,是一支重要的党的储备力量,它的发展壮大为党输入新鲜血液。新时代赋予学生党员新的历史使命。高质量党员教育管理是时代的要求,更是高校实现立德树人目标的重要抓手。目前,高职院校学生党支部在学生党员教育管理中存在两个方面的问题:学生党员自身存在的问题和学生党支部存在的问题,结合高职院校基层党建工作要求与学生工作实践提出了加强和改进学生党员教育管理的五条有效新路径。

关键词：加强和改进高职院校学生党支部学生教育管理

间充质干细胞来源外泌体在脑缺血再灌注损伤中神经保护作用的研究进展

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中国临床神经外科杂志 2024年第3期29卷 177-180页

作者：韩硕王君玉卢成寅侯立军上海长征医院神经外科上海200003

脑卒中是导致我国成年人残疾、死亡的首位原因,其中80%以上的脑卒中为缺血性脑卒中。缺血再灌注损伤是导致缺血性脑卒中病人残疾、死亡的常见原因。目前,针对缺血再灌注损伤的临床药物主要包括自由基清除剂、钙离子拮抗剂和兴奋性氨基... 详细信息

脑卒中是导致我国成年人残疾、死亡的首位原因,其中80%以上的脑卒中为缺血性脑卒中。缺血再灌注损伤是导致缺血性脑卒中病人残疾、死亡的常见原因。目前,针对缺血再灌注损伤的临床药物主要包括自由基清除剂、钙离子拮抗剂和兴奋性氨基酸拮抗剂等,疗效不理想。近年来,越来越多的研究者开始尝试应用干细胞治疗,但动物实验发现移植的干细胞在脑内存活率较低,很少有干细胞能分化为神经元。令人意外的是,研究发现干细胞可以通过旁分泌外泌体发挥神经保护作用。但天然外泌体靶向能力差,目前已经研发的工程性外泌体针对神经细胞具有主动靶向能力。本文对间充质干细胞来源外泌体在脑缺血再灌注损伤中的神经作用研究进展作一综述。

关键词：缺血性脑卒中缺血再灌注损伤间充质干细胞外泌体

Binding and Adsorption Energies of Heavy Metal Ions with Hapli-Udic Argosol and Ferri-Udic Argosol Particles

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Pedosphere 2007年第6期17卷 688-696页

作者： wang yu-jun LI Cheng-Bao wang Wei ZHOU Dong-Mei XU Ren-Kou Institute of Soil Science the Chinese Academy of Sciences P.O. Box 821 Nanjing 210008 （China） College of Resource and Environment Nanjing Agricultural University Nanjing 210095 （China）

Gibbs free binding energy and adsorption energy between cations and charged soil particles were used to evaluate the interactions between ions and soil particles. The distribution of Gibbs free adsorption energies could not be determined experimentally before the development of Wien effect measurements in dilute soil suspensions. In the current study, energy relationships between heavy metal ions and particles of Hapli-Udic Argosol （Alfisol） and Ferri-Udic Argosol were inferred from Wien effect measurements in dilute suspensions of homoionic soil particles （〈 2 μm） of the two soils, which were saturated with ions of five heavy metals, in deionized water. The mean Gibbs free binding energies of the heavy metal ions with Hapli-Udic Argosol and Ferri-Udic Argosol particles diminished in the order of Pb^2＋〉 Cd^2＋〉 Cu^2＋〉 Zn^2＋〉 Cr^3＋, where the range of binding energies for Hapli-Udic Argosol （7.25-9.32 kJ mol^-1） was similar to that for Ferri-Udic Argosol （7.43-9.35 kJ mol^-1）. The electrical field-dependent mean Gibbs free adsorption energies of these heavy metal ions for Hapli-Udic Argosol and for Ferri-Udic Argosol descended in the order： Cu^2＋〉 Cd2^＋〉 Pb^2＋〉 Zn^2＋〉 Cr^3＋, and Cd^2＋〉 Cu^2＋〉 Pb^2＋〉 Zn^2＋〉 Cr^3＋, respectively. The mean Gibbs free adsorption energies of Cu^2＋, Zn^2＋, Cd^2＋, Pb^2＋, and Cr^3＋ at a field strength of 200 kV cm^-1, for example, were in the range of 0.8-3.2 kJ mo1^-1 for the two soils.

关键词： adsorption energy Argosol binding energy heavy metal ion Wien effect