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Field experimental study on the effect of thawed depth of frozen alpine meadow soil on rill erosion by snowmelt waterflow

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International Soil and Water Conservation Research 2024年第1期12卷 54-63页

作者： Ying Zheng xiaonan shi Fan Zhang Tingwu Lei Chen Zeng Xiong Xiao Li Wang Guanxing Wang State Key Laboratory of Tibetan Plateau Earth System Resources and Environment(TPESRE)Institute of Tibetan Plateau ResearchChinese Academy of SciencesBeijing100101China University of Chinese Academy of Sciences Beijing100101China State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering Hohai UniversityNanjing210098China College of Water Resources and Civil Engineering China Agricultural UniversityBeijing100083China College of Geographic Science Hunan Normal UniversityChangsha410081China

Soil erosion by snow or ice melt waterflow is an important type of soil erosion in many high-altitude and high-latitude regions and is further aggravated by climate *** snowmelt waterflow erosion process is affected by soil freeze-thaws and is highly dynamically *** this study,a methodology was developed to conduct in situ field experiments to investigate the effects of the thawed depth of the frozen soil profile on snowmelt waterflow *** method was implemented on an alpine meadow soil slope at an altitude of 3700 m on the northeastern Tibetan *** erosion experiments involved five thawed soil depths of 0,10,30(35),50,and 80(100)mm under two snowmelt waterflow rates(3 and 5 L/min).When the topsoil was fully frozen or shallow-thawed(≤10 mm),its hydrothermal and structural properties caused a significant lag in the initiation of runoff and delayed soil erosion in the initial *** runoff and sediment concentration curves for fully frozen and shallow-thawed soil showed two-stage patterns characteristic of a sediment supply limited in the early stage and subject to hydrodynamic-controlled processes in the later ***,this effect did not exist where the thawed soil depth was greater than 30 *** deep-thawed cases(≥30 mm)showed normal hydrograph and sedigraph patterns similar to those of the unfrozen *** findings of this study are important for understanding the erosion rates of partially thawed soil and for improving erosion simulations in cold regions.

关键词： Snowmelt waterflow erosion Hillslope erosion process Soil freeze and thaw Runoff generation In situ experimental method

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Research on the Progress of Treating Gastroesophageal Reflux Disease with Modified Classic Traditional Chinese Medicine Prescription

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Proceedings of Anticancer Research 2024年第3期8卷 1-6页

作者： Haojie Fu Yahui Huang xiaonan shi Shaanxi University of Chinese Medicine Xianyang 712000Shaanxi ProvinceChina

Gastroesophageal reflux disease (GERD) is a high-incidence digestive system disease. Western medicine mainly uses drugs such as proton pump inhibitors to inhibit gastric acid secretion, but some patients are accompanied by symptoms such as non-acid reflux and gas reflux, which cannot effectively treat the disease. It is necessary to actively explore other treatment schemes. Traditional Chinese medicine (TCM) has a long history of research on gastroesophageal reflux disease, which emphasizes the treatment based on syndrome differentiation as a whole. Through the treatment of various and multi-component TCM prescriptions, the patient’s body condition can be adjusted, and the treatment effect on gastroesophageal reflux disease is reliable, which has obvious therapeutic advantages. To further clarify the treatment of gastroesophageal reflux disease, this study reviewed and analyzed the research progress of the treatment of liver disease with modified prescriptions, and the report is as follows.

关键词： Addition and subtraction of classic TCM prescriptions Gastroesophageal reflux disease Research progress Liver and stomach stagnation heat Qi stagnation and phlegm obstruction

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中外大学地理学通识教育模式与实践比较研究

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地理教学 2024年第16期 53-60页

作者：姜璐严萌史晓楠陆海波史培军北京师范大学地理科学学部北京100875

地理学通识课程作为大学通识教育的重要组成部分,旨在培养学生的地理认知能力和提升地理知识分析与应用能力。文章采用CiteSpace软件,对2013~2023年Web of Science(WOS)和中国知网(CNKI)数据库中关于大学通识教育和地理学通识教育的研... 详细信息

地理学通识课程作为大学通识教育的重要组成部分,旨在培养学生的地理认知能力和提升地理知识分析与应用能力。文章采用CiteSpace软件,对2013~2023年Web of Science(WOS)和中国知网(CNKI)数据库中关于大学通识教育和地理学通识教育的研究文献进行了可视化分析;同时使用定性比较分析法,梳理国内外(QS大学学校排名和地理学学科排名均较前的6所高校)地理学通识课程培养目标及要求、专业核心课程设定、学分构成及教学计划等方面的异同。研究表明:通识教育与地理学教育融合的研究引起学术界高度关注,瑞士洛桑大学、美国密歇根大学、南京大学和复旦大学是地理学通识教育课程改革的主要机构;中国、英国和美国高校在地理学通识课程的培养目标、课程设计和教学计划方面存在明显差异,中国高校注重培养学生的地理学应用技能和综合分析能力,英国高校侧重于地理与其他学科的交叉研究及实践应用,而美国高校强调地理专业技能和解决实际地理问题的能力。研究结果可为完善高等教育中的地理通识教育课程体系与创新大学地理学教育提供全球视角和参考。

关键词：通识教育地理能力 CiteSpace 文献计量分析比较研究

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Palladium-Catalyzed Skeletal Reorganization of Cyclobutanones Invoving Successive C—C Bond/C—H Bond Cleavage

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中国化学:英文版 2023年第14期41卷 1679-1683页

作者： Ruirui Li xiaonan shi Dongbing Zhao State Key Laboratory and Institute of Elemento-Organic Chemistry College of ChemistryNankai UniversityTianjin300071 China

The utilization of cyclobutanones as the synthon in transition metal catalysis has been made great *** C(carbonyl)−C bond of cyclobutanones can be cleaved through strain *** those advancements,the main catalysts in literature are Rh catalysts or Ni catalysts and the reaction with C—H bond is still ***,we realized the first palladium-catalyzed skeletal reorganization of cyclobutanones involving successive cleavage of C(carbonyl)−C bonds and C—H bond cleavage,which constitutes an rapid access to diverse *** contrast to the previous Rh-catalytic system,the Pd-catalytic system herein involves different mechanism and features several advantages:1)no need of directing group to facilitate the C(carbonyl)−C bond cleavage;2)much milder reaction condition and 3)simplified work-up.

关键词： Cyclobutanones C-C activation C-H activation Palladium catalysis Ring expansion

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Runoff and sediment yield in relation to precipitation,temperature and glaciers on the Tibetan Plateau

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International Soil and Water Conservation Research 2022年第2期10卷 197-207页

作者： Fan Zhang Chen Zeng Guanxing Wang Li Wang xiaonan shi Key Laboratory of Tibetan Environment Changes and Land Surface Processes Institute of Tibetan Plateau ResearchChinese Academy of SciencesBeijing100101China CAS Center for Excellence in Tibetan Plateau Earth Sciences Beijing100101China University of Chinese Academy of Sciences Beijing100101China

The riverine sediment is an essential carrier for nutrients and pollutants delivery and is considered as an important indicator of land degradation and environmental *** growing interest in envi-ronmental changes over the Tibetan Plateau,this study investigated mean annual runoff and sediment yield from eight headwater catchments in relation to annual precipitation,air temperature,and glacier area ratio,*** show that runoff(Q)is positively correlated with both precipitation(P)and temperature(T),i.e.,Q¼0.357Pþ20.3T-6.4,indicating combined water supply from rainfall and melt-water,increase of which may exceed the evapotranspiration water loss caused by temperature *** yield(S)shows an inverted parabolic relationship with precipitation and at the same time positive correlation with glacier area ratio(Ag),i.e.,S¼0.000609 P2-0.470Pþ48.5 Agþ202.53,indicating that sediment yield is a minimum at about 500e600 mm of precipitation,increasing sharply on both sides of this minimum in one case owing to decreased vegetation protection and in the other to enhanced erosive power and that erosion rate in the glacierized area is generally higher than non-glacierized *** variation in sediment yield with precipitation can be explained by the operation of two factors,i.e.,rainfall erosive action that increases continuously with increase in precipitation,and vegetation protective action that is unity for zero precipitation and decreases with increases in *** above results may be useful in visualizing not only variations in rates of erosion among climatic zones on the Tibetan Plateau but also the probable changes of erosion during a climatic change.

关键词： Alpine catchment Climate condition Glacier erosion Runoff Sediment yield

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Hydrogen Peroxide Electrosynthesis in a Strong Acidic Environment Using Cationic Surfactants

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Precision Chemistry 2024年第4期2卷 129-137页

作者： Zachary Adler Xiao Zhang Guangxia Feng Yaping shi Peng Zhu Yang Xia xiaonan Shan Haotian Wang Rice University Department of Chemical and Biomolecular EngineeringHoustonTexas 77005United States University of Houston Department of Electrical and Computer EngineeringHoustonTexas 77004United States

The two-electron oxygen reduction reaction(2e^(−)-ORR)can be exploited for green production of hydrogen peroxide(H_(2)O_(2)),but it still suffers from low selectivity in an acidic electrolyte when using non-noble metal ***,inspired by biology,we demonstrate a strategy that exploits the micellization of surfactant molecules to promote the H_(2)O_(2)selectivity of a low-cost carbon black catalyst in strong acid *** surfactants near the electrode surface increase the oxygen solubility and transportation,and they provide a shielding effect that displaces protons from the electric double layer(EDL).Compared with the case of a pure acidic electrolyte,we find that,when a small number of surfactant molecules were added to the acid,the H_(2)O_(2)Faradaic efficiency(FE)was improved from 12%to 95%H_(2)O_(2)under 200 mA cm−2,suggesting an 8-fold *** in situ surface enhanced Raman spectroscopy(SERS)and optical microscopy(OM)studies suggest that,while the added surfactant reduces the electrode’s hydrophobicity,its micelle formation could promote the O2 gas transport and its hydrophobic tail could displace local protons under applied negative potentials during catalysis,which are responsible for the improved H_(2)O_(2)selectivity in strong acids.

关键词： electrocatalysis hydrogen peroxide electrosynthesis oxygen reduction reaction interfacial engineering surfactant CTAB

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Experimental study on the effects of multiple factors on spring meltwater erosion on an alpine meadow slope

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International Soil and Water Conservation Research 2020年第2期8卷 116-123页

作者： xiaonan shi Fan Zhang Li Wang Muhammad Dodo Jagirani Chen Zeng Xiong Xiao Guanxing Wang Key Laboratory of Tibetan Environment Changes and Land Surface Processes Institute of Tibetan Plateau ResearchChinese Academy of Sciences(CAS)Beijing100101China CAS Center for Excellence in Tibetan Plateau Earth Sciences Beijing100101China University of Chinese Academy of Sciences Beijing100049China

Meadow degradation provides a major indication of increased soil erosion in alpine *** soil erosion is observed during the spring in particular because soil thawing coincides with the period of snowmelt and the meadow coverage is very low at this *** relating to soil erosion caused by spring meltwater are,however,limited and ***,a field experimental study was conducted in a typical meadow in the Binggou watershed on the northern edge of the Tibetan Plateau to assess the impact of multiple factors on spring meltwater erosion on an alpine meadow *** multiple factors included three flow rates(1,2,and 3 L/min),four slope gradients(10°,15°,20°,and 25°),and three underlying surface conditions(meadow,disturbed meadow,and alluvial soil).An equal volume of concentrated meltwater flow was used in all *** results showed that rapid melting at a high flow rate could accelerate soil erosion;as the flow rate increased from 1 to 3 L/min,the total surface runoff increased by a factor of 0.7 and the total sediment yield increased by more than *** in-fluence of the slope gradient on the amount of runoff was positively linear and the influence was relatively low;when the slope increased from 10°to 25°,the total runoff only increased by 16%.However,the slope gradient had a strong impact on soil *** total sediment yield doubled when the slope increased from 10°to 20°and then slightly decreased at 25°.The meadow could effectively reduce soil erosion,although when the meadow was disturbed,the total runoff increased by 60%and the sediment yield by a factor of *** total runoff from the alluvial soil doubled in comparison to the meadow,while the sediment yield increased nearly *** findings of this study could be helpful to understand the characteristics and impact of multiple controlling factors of spring meltwater *** also aims to provide a scientific basis for an improved management of alpine meadows

关键词： Meltwater erosion Alpine meadow Slope erosion Impact factors

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Determination and impact factor analysis of hydrodynamic dispersion coefficient within a gravel layer using an electrolyte tracer method

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International Soil and Water Conservation Research 2016年第2期4卷 87-92页

作者： xiaonan shi Tingwu Lei Yan Yan Fan Zhang State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau Institute of Water and Soil ConservationChinese Academy of Sciences and Ministry of Water ResourcesYangling712100 ShaanxiPR China Key Laboratory of Tibetan Environment Changes and Land Surface Processes Institute of Tibetan Plateau ResearchChinese Academy of SciencesBeijing 100101PR China College of Water Resources and Civil Engineering China Agricultural UniversityBeijing 100083PR China HydroChina Kunming Engineering Corporation LTDKunming 650000YunnanPR China

Hydrodynamic dispersion is a measure for describing the process of solute transport in porous *** the dispersion of water flow within gravel is essential for the prediction of solute transport especially nonpoint source pollutants migration in alpine watersheds where the land surface is typically covered with *** this study,an integrated model and experimental method using an electrolyte tracer is proposed for determination of the hydrodynamic dispersion *** experimental scenarios were designed to measure electrolyte tracer transport processes in both free water flow and gravel layer flow under different slope gradients and transport ***,the measured data were used to simultaneously calculate both the hydrodynamic dispersion coefficient and flow velocity by fitting the experimental data with the mathematical ***,as a critical feature of hydrodynamic dispersion,was determined as well under the two specified ***,the impact mechanisms of the gravel layer and factors related to the dispersion processes were comprehensively *** results indicate that the presence of a gravel layer significantly reduces flow velocity and the hydrodynamic dispersion coefficient,but increases solute *** the flow within gravel layers,with much lower velocity,the positive effect of the gravel layer on dispersivity may be neutralized or even surpassed by the negative effect of flow *** results should be helpful in characterizing the dispersion processes of water flow within gravel layer and hence in predicting solute transport,especially in nonpoint source pollutants migration in alpine watersheds where the land surface is richly covered with gravel.

关键词： Hydrodynamic dispersion coefficient Flow velocity Gravel layer Electrolyte tracer

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论侵害英雄烈士名誉、荣誉罪的保护法益

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中南大学学报（社会科学版） 2023年第2期29卷 70-82页

作者：李冠煜石晓南华中科技大学法学院湖北武汉430074

关于侵害英雄烈士名誉、荣誉罪的保护法益,目前存在着集体法益和个人法益、单一法益与复合法益之争。英雄烈士的名誉、荣誉同时体现着个人利益和公共利益,但在刑法对其保护路径的选择上,将其定位为个人法益,不具有理论、实践上的妥当性... 详细信息

关于侵害英雄烈士名誉、荣誉罪的保护法益,目前存在着集体法益和个人法益、单一法益与复合法益之争。英雄烈士的名誉、荣誉同时体现着个人利益和公共利益,但在刑法对其保护路径的选择上,将其定位为个人法益,不具有理论、实践上的妥当性。根据法益保护理论,法益一元说显然无法与刑法发挥风险应对、社群整合机能的要求相协调,无助于本罪法益的规范解释。法益二元说承认集体法益与个人自由发展及其基本权利实现的价值关联,但无需还原为个人法益。这一观点用于解释本罪法益更为合理。英雄烈士作为国家历史符号,对其名誉、荣誉的保护,旨在保障国家内部架构条件即公民认同感这一维系国家存立的集体性心理。它有利于强化共同体的价值凝聚力和精神向心力,是保障国家存续的必不可少的心理条件,由此可以证成其属于集体法益。根据二元说的立场,在价值面上,本罪法益与个人自由和人格发展具有关联性,具备立法的正当性;在存在面上,通过犯罪对象的确定和罪量要素的认定,可以为司法识别保护法益提供更加明显的外在标识。

关键词：侵害英雄烈士名誉、荣誉罪集体法益国家内部架构条件国家存立心理条件

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基于脱细胞方法制备3D植物肝组织工程支架及表征

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中国组织工程研究 2024年第29期28卷 4645-4651页

作者：胡婧婧何松霖张大旭赵烁史潇楠李伟龙叶淑君王静怡郭全义阎丽解放军总医院第二医学中心老年医学科北京市100853 解放军总医院第一医学中心骨科研究所骨科再生医学北京市重点实验室全军骨科战创伤重点实验室北京市100853

背景:组织工程为肝衰竭这一临床困境带来了新的希望,通过简单的制备方法制备植物脱细胞纤维支架对肝脏组织工程具有重要意义。目的:采用新鲜苹果切片和十二烷基硫酸钠溶液制备苹果组织脱细胞支架材料,并评估其生物相容性。方法:将新鲜... 详细信息

背景:组织工程为肝衰竭这一临床困境带来了新的希望,通过简单的制备方法制备植物脱细胞纤维支架对肝脏组织工程具有重要意义。目的:采用新鲜苹果切片和十二烷基硫酸钠溶液制备苹果组织脱细胞支架材料,并评估其生物相容性。方法:将新鲜苹果分别采用磷酸盐缓冲液和十二烷基硫酸钠溶液进行脱细胞处理,然后用磷酸盐缓冲液进行脱毒获得处理后的苹果组织和苹果脱细胞支架材料,然后在扫描电镜下观察苹果材料的脱细胞效果。实验从BALB/C小鼠腹股沟脂肪中提取脂肪干细胞,并且通过流式细胞术鉴定其干细胞相关标记物(CD45,CD34,CD73,CD90,CD105)的表达。然后分为无支架对照组和有支架组,在两组中接种等量脂肪干细胞,通过CCK-8、苏木精-伊红染色、鬼笔环肽骨架染色评价该脱细胞支架与脂肪干细胞的生物相容性,在光学显微镜、扫描电镜下观察细胞在支架上的黏附及生长情况。然后将支架分为非诱导组和成肝诱导组,将脂肪干细胞种植在脱细胞苹果支架上,分别在普通培养基和成肝诱导培养基中培养14 d后进行对比,通过肝细胞标记物(白蛋白、细胞角蛋白18、细胞色素P450家族1亚家族1)进行免疫荧光染色,通过酶联免疫吸附实验来检测白蛋白、甲胎蛋白的分泌情况,并通过扫描电镜观察支架上诱导培养的细胞形态,验证该脱细胞支架材料上肝细胞相关蛋白的表达。最后,实验通过将钴60照射消毒后的苹果脱细胞支架移植于小鼠肝脏表面,28 d后通过大体观及苏木精-伊红染色观察该支架的降解情况。结果与结论:①扫描电镜结果显示,脱细胞后的苹果支架材料具有约100μm大小的孔隙结构,不存在残余细胞。②通过流式细胞学鉴定,提取培养的细胞为脂肪间充质干细胞。③CCK-8结果表明,所制备的苹果组织脱细胞支架材料无细胞毒性;苏木精-伊红染色和鬼笔环肽骨架染色观察到脂肪间充质干细胞能够在苹果组织脱细胞支架上黏附和聚集生长。④免疫荧光染色、酶联免疫吸附实验结果显示,培养在苹果组织脱细胞支架上的脂肪间充质干细胞高表达白蛋白、甲胎蛋白、细胞角蛋白18及细胞色素P450家族1亚家族1肝脏相关蛋白,说明被诱导分化为了具有肝细胞功能的肝细胞样细胞。⑤干预7 d时植入的苹果脱细胞支架与肝脏融合,部分支架已经降解,干预28 d时苹果脱细胞支架已完全降解,被新生组织替代。⑥结果表明,来源于苹果组织制备的脱细胞支架材料具有良好的生物相容性,可促进脂肪间充质干细胞的增殖、黏附及成肝细胞分化。

关键词：植物组织支架脱细胞肝衰竭脂肪间充质干细胞组织工程肝细胞样细胞

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