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Modified Method for Estimating Organic Carbon Density in Discontinuous Karst Soil Using Ground-Penetrating Radar and Geostatistics

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Journal of Mountain Science 2015年第5期12卷 1229-1240页

作者： LI Lei xia yin-hang LIU Shu-juan Zhang Wei CHEN xiang-bi ZHENG Hua QIU Hu-sen HE Xun-yang SU Yi-rong Key Laboratory of Agro-ecological Processes in Subtropical Region Institute of Subtropical Agriculture Chinese Academy of Sciences Huanjiang Observation and Research Station for Karst Eco-systems University of Chinese Academy of sciences Guangxi Institute of Subtropical Crops

The conventional method which assumes the soil distribution is continuous was unsuitable for estimating soil organic carbon density(SOCD) in Karst areas because of its discontinuous soil distribution. The accurate estimation of SOCD in Karst areas is essential for carbon sequestration assessment in China. In this study, a modified method,which considers the vertical proportion of soil area in the profile when calculating the SOCD, was developed to estimate the SOCD in a typical Karst peak-cluster depression area in southwest China. In the modified method, ground-penetrating radar(GPR) technology was used to detect the distribution and thickness of soil. The accuracy of the method was confirmed through comparison with the data obtained using a validation method, in which the soil thickness was measured by excavation. In comparison with the conventional method and average-soil-depth method,the SOCD estimated using the GPR method showed the minimum relative error with respect to that obtained using the validation method. At a regional scale, the average SOCDs at depths of 0-20 cm and 0-100 cm, which were interpolated by ordinary kriging,were 1.49(ranging from 0.03-5.65) and 2.26(0.09-11.60) kgm-2based on GPR method in our study area(covering 393.6 hm2), respectively. Therefore, the modified method can be applied on the accurate estimation of SOCD in discontinuous soil areas such as Karst regions.

关键词： Discontinuous soil Organic carbondensity Soil distribution Estimation method Ground penetrating radar Karst Peak clusterdepression

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Inhibition of the cGAS–STING pathway:contributing to the treatment of cerebral ischemia-reperfusion injury

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Neural Regeneration Research 2025年第7期20卷 1900-1918页

作者： hang Yang Yulei xia Yue Ma Mingtong Gao Shuai Hou Shanshan Xu Yanqiang Wang School of Clinical Medicine Shandong Second Medical UniversityWeifangShandong ProvinceChina Department of Emergency The Affiliated Hospital of Weifang Medical UniversityWeifangShandong ProvinceChina Department of Neurology Ⅱ The Affiliated Hospital of Weifang Medical UniversityWeifangShandong ProvinceChina

The cGAS–STING pathway plays an important role in ischemia-reperfusion injury in the heart,liver,brain,and kidney,but its role and mechanisms in cerebral ischemia-reperfusion injury have not been systematically ***,we outline the components of the cGAS–STING pathway and then analyze its role in autophagy,ferroptosis,cellular pyroptosis,disequilibrium of calcium homeostasis,inflammatory responses,disruption of the blood–brain barrier,microglia transformation,and complement system activation following cerebral ischemia-reperfusion *** further analyze the value of cGAS–STING pathway inhibitors in the treatment of cerebral ischemia-reperfusion injury and conclude that the pathway can regulate cerebral ischemia-reperfusion injury through multiple *** of the cGAS–STING pathway may be helpful in the treatment of cerebral ischemia-reperfusion injury.

关键词： calcium homeostasis cellular autophagy cerebral ischemia-reperfusion injury cGAS–STING pathway ferroptosis gut–brain–microbiota axis inflammatory light chain 3 microglial cells Syntaxin-17 protein

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红壤丘陵区土壤有机碳组分对土地利用方式的响应特征

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环境科学 2020年第3期41卷 1466-1473页

作者：章晓芳郑生猛夏银行胡亚军苏以荣陈香碧中国科学院亚热带农业生态研究所亚热带农业生态过程重点实验室长沙410125 中国科学院大学北京100049

土地利用方式影响土壤有机碳(SOC)及其组分,进而决定了碳库的稳定性.以林地为参照,分析我国红壤丘陵区农田(水田和旱地)SOC及其活性组分[可溶性有机碳(DOC)、微生物生物量碳(MBC)和颗粒有机碳(POC)]和惰性组分[矿物结合态有机碳(MAOC)]... 详细信息

土地利用方式影响土壤有机碳(SOC)及其组分,进而决定了碳库的稳定性.以林地为参照,分析我国红壤丘陵区农田(水田和旱地)SOC及其活性组分[可溶性有机碳(DOC)、微生物生物量碳(MBC)和颗粒有机碳(POC)]和惰性组分[矿物结合态有机碳(MAOC)]含量,探讨土壤有机碳组分对土地利用方式的响应特征.结果表明,与旱地和林地相比,水田SOC、 MBC、 POC和MAOC含量均为最高.DOC含量以林地显著高于旱地和水田(P林地>旱地.MAOC含量以水田最高、旱地最低,MAOC/SOC则以旱地最高、水田最低.相关分析表明,水田、旱地和林地中MBC、 POC和MAOC分别与SOC呈极显著正相关(P0.05);旱地、林地中POC与MBC呈极显著正相关(P<0.001);水田、旱地MAOC与MBC呈极显著正相关(P<0.001);3种土地利用方式下POC与MAOC呈极显著正相关(P<0.001),POC/MAOC以水田最大,旱地最低.因而,与旱地和林地相比,水田SOC的活性组分比例高、惰性组分比例低,且其活性组分POC与微生物生物量关系不紧密,而惰性组分与微生物生物量显著相关.综上,农业利用显著改变红壤丘陵区土壤有机碳及其组成,水田虽有利于SOC固持,但其不稳定性组分占比较高,可能容易因不当耕作管理而丢失.

关键词：红壤丘陵区水田旱地林地土壤有机碳(SOC) 有机碳组分

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2D phosphides heterostructures on titanium microfiltration membrane for enhanced ampere-level current density overall seawater splitting

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Nano Research 2025年第1期18卷 249-259页

作者： Wenjing Dai Xin Wang Yulong Ma Sisi He Ming Chen Zhaohui yin Shuheng Tian Maolin Wang Shixiang Yu hang Zhang Yuanzhe Wang Hong Wang Jianxin Li Faming Gao Bowen Cheng Yun Wang Zhen yin Ding Ma Tianjin Key Laboratory of Brine Chemical Engineering and Resource Eco-utilization College of Chemical Engineering and Materials ScienceTianjin University of Science and TechnologyTianjin 300457China State Key Laboratory of Biobased Fiber Manufacturing Technology Tianjin University of Science and TechnologyTianjin 300457China Haian Institute of High-Tech Research Nanjing UniversityHaian 226600China Beijing National Laboratory for Molecular Sciences College of Chemistry and Molecular EngineeringPeking UniversityBeijing 100871China State Key Laboratory of Separation Membranes and Membrane Processes Separation Membrane Science and Technology International Joint Research CentreTiangong UniversityTianjin 300387China Centre for Catalysis and Clean Energy School of Environment and ScienceGold Coast CampusGriffith UniversitySouthportQueensland 4222Australia

The advancement of direct seawater electrolysis is a significant step towards sustainable hydrogen production,addressing the critical need for renewable energy sources and efficient resource ***,direct seawater electrolysis has to face several challenges posed by the corrosiveness of highly concentrated chloride and the competitive chlorine evolution reaction(ClER).To overcome these issues,we designed a novel NiP_(2)@CoP electrocatalyst on a porous titanium microfiltration(Ti MF)*** obtained bifunctional NiP_(2)@CoP catalyst outperforms the Pt/C and IrO_(2),as evidenced by its low overpotentials of 192 and 425 mV at a current density of 500 mA·cm^(-2) for hydrogen evolution reaction(HER)and oxygen evolution reaction(OER)in alkaline seawater(1 M KOH+0.5 M NaCl),***,only 231 and 569 mV overpotentials are required at the current density of 1500 mA·cm^(-2) towards HER and OER in alkaline seawater,*** importantly,no ClER was observed,demonstrating its excellent selectivity to *** selection of porous Ti MF membrane as an electrode substrate further enhances the performance by providing a robust structure that promotes the fast generation and release of gas *** promising outcomes obtained with NiP_(2)@CoP catalysts on Ti MF support,therefore,pave the way for the commercial viability of direct seawater electrolysis technologies at industrial-level current densities.

关键词： direct seawater electrolysis porous titanium microfiltration membrane phosphides heterostructures NiP_(2)@CoP electrocatalyst excellent selectivity to oxygen evolution reaction(OER)

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双季稻复种冬季马铃薯提高真菌α多样性和腐生真菌相对丰度促进秸秆腐解

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植物营养与肥料学报 2024年第6期30卷 1075-1091页

作者：田茂平姜东海邱智容苗旭晨夏银行陈涛张振华赵紫薇湖南农业大学资源学院湖南长沙410128 衡阳市气象局湖南衡阳421000

【目的】秸秆还田是提高土壤肥力和作物产量的有效途径,复种模式影响土壤真菌群落结构和功能,进而影响秸秆在土壤中的降解程度。通过研究不同复种模式下秸秆的降解特征,为提高秸秆还田效益提供依据。【方法】培养试验的土壤取自3个三熟... 详细信息

【目的】秸秆还田是提高土壤肥力和作物产量的有效途径,复种模式影响土壤真菌群落结构和功能,进而影响秸秆在土壤中的降解程度。通过研究不同复种模式下秸秆的降解特征,为提高秸秆还田效益提供依据。【方法】培养试验的土壤取自3个三熟复种地块:稻—稻—紫云英(RRA)、稻—稻—油菜(RRO)、稻—稻—马铃薯(RRP),和两个两熟复种地块:稻—稻—冬板田(RRN)、稻—稻—冬泡田(RRI),采集时间均为早稻扬花期。每个土壤均设不添加和添加秸秆(0.5 g秸秆与80 g风干土混合)两个处理,然后置于250 mL棕色瓶中厌氧培养120天。在培养期内,定期取样检测CO_(2)排放量,破坏性采集土样测定土壤微生物生物量碳、氮含量和4种秸秆降解酶活性,利用扩增子高通量测序技术分析真菌群落结构。【结果】与两熟复种模式相比,三熟复种模式提高了土壤微生物生物量碳、氮含量以及β-葡萄糖苷酶、β-纤维二糖苷酶、β-木糖苷酶和漆酶活性。三熟与两熟复种土壤之间真菌群落结构存在差异,RRP地块土壤真菌ASV数目、Chao1、ACE和Shannon指数,以及分解半纤维素、纤维素和木质素等有机物质的无茎真菌属(Acaulium)、被孢霉属(Mortierella)、粉枝孢属(Oidiodendron)的相对含量显著高于两熟地块。共现性网络分析发现,与RRN相比,RRO和RRP复种模式增加了土壤真菌网络的复杂性,提高了网络中子囊菌门、壶菌门等具有秸秆分解潜力的关键物种的数量。冗余分析及回归分析等发现,全磷是复种系统中影响土壤真菌群落结构及秸秆降解酶类活性的最重要的环境因子。【结论】相比于冬闲两熟复种模式,三熟复种模式可增加微生物生物量,提高秸秆降解酶活性,同时提高真菌α多样性以及增加腐生真菌的相对丰度,进而更有效地促进秸秆的分解。双季稻结合冬季复种马铃薯是促进还田秸秆腐解、提升土壤肥力的有效复种模式。

关键词：复种模式秸秆分解秸秆分解酶活性真菌群落结构α多样性腐生真菌

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基于探地雷达技术估算喀斯特峰丛洼地不同坡位土壤有机碳密度的方法

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农业环境科学学报 2015年第5期34卷 920-927页

作者：夏银行黎蕾陈香碧何寻阳刘坤平吴金水苏以荣中国科学院亚热带农业生态研究所亚热带农业生态过程重点实验室长沙410125 中国科学院大学北京100049 中国科学院环江喀斯特生态系统观测研究站广西环江547100

在典型喀斯特峰丛洼地区按上、中、下坡位和洼地分别选取四个样方,利用探地雷达技术探测土壤深度,获得各层次土壤体积分数,结合土壤剖面采样获得的土壤有机碳含量、石砾含量和容重等数据,计算土壤有机碳密度。结果表明:该峰丛洼地区上... 详细信息

在典型喀斯特峰丛洼地区按上、中、下坡位和洼地分别选取四个样方,利用探地雷达技术探测土壤深度,获得各层次土壤体积分数,结合土壤剖面采样获得的土壤有机碳含量、石砾含量和容重等数据,计算土壤有机碳密度。结果表明:该峰丛洼地区上、中、下坡位的土壤主要集中在0~30 cm深度范围内,体积分数范围为72%±16%~78%±6%,洼地的土壤则主要集中在0~70 cm,体积分数为64%±17%;土壤剖面0~30 cm内有机碳含量逐层显著下降(P<0.05),在深度30 cm以下下降趋势变缓,表层土壤有机碳含量从上坡至洼地逐渐降低,符合喀斯特地区特有的"养分倒置"现象;基于探地雷达法测得的0~20 cm土壤有机碳密度由上坡至洼地逐渐减小,上坡与洼地差异显著(P<0.05),而0~100 cm土壤有机碳密度则洼地显著大于坡地(P<0.05);探地雷达法与"平均深度法"相比,后者对前者的相对误差为0.3%~14.5%,未达到显著差异。通过研究建立了基于探地雷达准确获取土壤深度的土壤有机碳密度的估算方法,适用于喀斯特非连续性土壤,为进一步准确估算喀斯特地区土壤有机碳储量提供了更可靠的方法。

关键词：喀斯特峰丛洼地探地雷达土壤分布土壤有机碳密度

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稻田微氧层和还原层土壤有机碳矿化对氮素添加的响应

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环境科学 2023年第11期44卷 6248-6256页

作者：毛婉琼夏银行马冲朱光旭王忠诚涂强陈香碧吴金水苏以荣中国科学院亚热带农业生态研究所亚热带农业生态过程重点实验室长沙410125 中国科学院大学北京100049 湖南农业大学资源环境学院长沙410128 贵阳学院生物与环境工程学院贵阳550005 中南林业科技大学林学院长沙少410004 赫姆霍兹抗感染国际实验室山东大学赫姆霍兹生物技术研究所微生物技术国家重点实验室青岛266237

田间条件下,淹水稻田由于上覆水中溶解氧的扩散作用,使其表层土壤存在约1 cm厚的微氧层,这个特殊层次中碳氮转化的特征尚未明晰.以亚热带典型稻田土壤为对象,采用100 d室内模拟培养试验,结合^(13)C稳定同位素示踪和磷脂脂肪酸(PLFA)分... 详细信息

田间条件下,淹水稻田由于上覆水中溶解氧的扩散作用,使其表层土壤存在约1 cm厚的微氧层,这个特殊层次中碳氮转化的特征尚未明晰.以亚热带典型稻田土壤为对象,采用100 d室内模拟培养试验,结合^(13)C稳定同位素示踪和磷脂脂肪酸(PLFA)分析技术,研究稻田土壤微氧层(0~1 cm)和还原层(1~5 cm)外源新鲜有机碳(^(13)C-水稻秸秆)和原有土壤有机碳矿化对氮肥施用[(NH4)2SO_(4)]的响应规律及其微生物过程.结果表明,氮素添加使土壤总CO_(2)和^(13)C-CO_(2)累积排放量分别提高11.4%和12.3%;培养结束时,氮素添加下还原层比微氧层土壤总有机碳含量和^(13)C回收率分别降低2.4%和9.2%.培养前期(5 d),氮素添加提高还原层微生物总PLFAs,且细菌和真菌PLFAs响应一致,但对微氧层微生物丰度无显著影响;氮素添加对微氧层和还原层总^(13)C-PLFAs丰度均无显著影响,但^(13)C标记细菌和真菌丰度显著降低.培养后期(100 d),氮素添加对微生物总PLFAs的影响与前期一致;氮素添加显著增加还原层^(13)C标记总量及细菌和真菌PLFAs含量,但对微氧层总^(13)C-PLFAs丰度无显著影响.培养期间,还原层土壤铵态氮含量高于微氧层.因此,施加氮素提高了稻田还原层土壤微生物活性,可能是由于还原层土壤具有更高的铵态氮,而大部分微生物偏好利用铵态氮,使还原层微生物生长和活性强于微氧层,进而加速还原层有机碳的微生物利用和分解;与之对应,微氧层土壤由于氨氧化作用,速效氮更多以硝态氮形态存在,因偏好利用硝态氮的微生物缺乏,限制了微氧层有机碳的微生物代谢.综上,氮肥施用增强稻田土壤有机碳矿化损失,但以微氧层响应弱于还原层,提示微氧层对土壤有机碳有一定保护作用.本研究强调了稻田土体的非均一性,其微氧层碳氮转化的特殊性不可忽视,研究结果对优化稻田种植系统氮肥施用形态和方法有一定启示意义.

关键词：稻田土壤微氧层还原层土壤有机碳水稻秸秆氮素添加磷脂脂肪酸(PLFAs)

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Semi-supervised learning based hybrid beamforming under time-varying propagation environments

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Digital Communications and Networks 2024年第4期10卷 1168-1177页

作者： yin Long hang Ding Simon Murphy School of Computer Science and Technology Southwest University of Science and TechnologyMianyang621000China Department of Computing Science University of AlbertaEdmontonT6G 2R3Canada

Hybrid precoding is considered as a promising low-cost technique for millimeter wave(mm-wave)massive Multi-Input Multi-Output(MIMO)*** this work,referring to the time-varying propagation circumstances,with semi-supervised Incremental Learning(IL),we propose an online hybrid beamforming ***,given the constraint of constant modulus on analog beamformer and combiner,we propose a new broadnetwork-based structure for the design model of hybrid *** with the existing network structure,the proposed network structure can achieve better transmission performance and lower ***,to enhance the efficiency of IL further,by combining the semi-supervised graph with IL,we propose a hybrid beamforming scheme based on chunk-by-chunk semi-supervised learning,where only few transmissions are required to calculate the label and all other unlabelled transmissions would also be put into a training data *** the existing single-by-single approach where transmissions during the model update are not taken into the consideration of model update,all transmissions,even the ones during the model update,would make contributions to model update in the proposed *** the model update,the amount of unlabelled transmissions is very large and they also carry some information,the prediction performance can be enhanced to some extent by these unlabelled channel *** results demonstrate the spectral efficiency of the proposed method outperforms that of the existing single-by-single ***,we prove the general complexity of the proposed method is lower than that of the existing approach and give the condition under which its absolute complexity outperforms that of the existing approach.

关键词： Hybrid beamforming Time-varying environments Broad network Semi-supervised learning Online learning

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Effect of radial heat conduction on effective thermal conductivity of carbon nanotube bundles

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Science China(Technological Sciences) 2018年第12期61卷 1959-1966页

作者： WANG JianLi SONG YaMei Zhang YuFeng HU YuHan yin hang GU YunFeng xia Re CHEN YunFei Jiangsu Key Laboratory for Design and Manufacture of Micro-Nano Biomedical Instruments Southeast University College of Electronic and Mechanical Engineering Nanjing Forestry University Key Laboratory of Hydraulic Machinery Transients (Wuhan University) Ministry of Education

The effect of the radial heat conduction on the effective thermal conductivity of carbon nanotube(CNT) bundles is studied by the nonequilibrium molecular dynamics(NEMD) method. The hexagonal CNT bundle consists of seven(10, 10) single-walled carbon nanotubes(SWCNTs). The radial heat conduction is induced by creating the vacancy defects in some segments of the constituent CNTs. Combined with the temperature differences and the inter-tube thermal resistances at the different segments,the radial heat flow in the CNT bundle is calculated. The maximum percentage of the radial heat flow is less than 7% with the presence of four defective CNTs, while the resultant decrement of the effective thermal conductivity of the bundle is about 18%.The present results indicate that the radial heat flow can significantly diminish the axial heat conduction in the CNT bundles,which probably explains the smaller effective thermal conductivity in the CNT assemblies compared to that of the individual CNTs.

关键词： axial thermal conductivity carbon nanotube bundle inter-tube thermal resistance radial heat flow

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Theoretical investigation on the excited state intramolecular proton transfer in Me_(2)N substituted flavonoid by the time-dependent density functional theory method

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Chinese Physics B 2018年第5期27卷 534-538页

作者： hang yin ying Shi Institute of Atomic and Molecular Physics Jilin UniversityChangchun 130012China State Key Laboratory of Supramolecular Structure and Materials College of ChemistryJilin UniversityChangchun 130012China

Time-dependent density functional theory(TDDFT)method is used to investigate the details of the excited state intramolecular proton transfer(ESIPT)process and the mechanism for temperature effect on the Enol^(*)/Keto^(*)emission ratio for the Me_(2)N-substited flavonoid(MNF)*** geometric structures of the S_(0) and S_(1) states are denoted as the Enol,Enol^(*),and Keto*.In addition,the absorption and fluorescence peaks are also *** is noted that the calculated large Stokes shift is in good agreement with the experimental ***,our results confirm that the ESIPT process happens upon photoexcitation,which is distinctly monitored by the formation and disappearance of the characteristic peaks of infrared(IR)spectra involved in the proton transfer and in the potential energy ***,the calculations of highest occupied molecular orbital(HOMO)and lowest unoccupied molecular orbital(LUMO)reveal that the electronegativity change of proton acceptor due to the intramolecular charge redistribution in the S_(1) state induces the ***,the thermodynamic calculation for the MNF shows that the Enol^(*)/Keto^(*)emission ratio decreasing with temperature increasing arises from the barrier lowering of ESIPT.

关键词： time-dependent density functional theory excited state intramolecular proton transfer intramolecular charge transfer transition state

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