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Evaluating the thermal environment of urban land surfaces in Yakutsk,a city located in a region of continuous permafrost

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Advances in Climate Change Research 2024年第1期15卷 113-123页

作者： xiang-Long LI Ze ZHANG Jin-Xin LU Anatoli BROUCHKOV Qing-kai YAN Qi-Hao YU Sheng-Rong ZHANG Andrey MELNIKOV School of Civil Engineering and Transportation Institute of Cold Regions Science and EngineeringPermafrost InstituteNortheast Forestry UniversityHarbin150040China China Railway Qinghai-Tibet Group Company Xining 810000China Department of Geocryology Faculty of GeologyLomonosov Moscow State UniversityMoscow 119234Russian Federation State Key Laboratory of Frozen Soil Engineering Northwest Institute of Eco Envi ronment and Re sourcesChinese Academy of SciencesLanzhou 730000China Melnikov Permafrost Institute Siberian BranchRussian Academy of ScienceYakutsk 677010Russian Federation

Rapid urbanization has led to changes in the urban land surface thermal ***,there are still much unknown about the urban land surface thermal conditions in permafrost *** is a unique geological environment,changes in the urban land surface thermal environment may trigger geological disasters caused by permafrost *** study utilized remote sensing data and geographic de-tectors to identify the dynamic changes in land surface temperature(LST)and land use/land cover(LU/LC)in Yakutsk,as well as the potential factors contributing to LST *** 1992 and 2020,the built-up area in Yakutsk increased by 36%,and the annual average LST in Yakutsk has risen by 6.67℃,accompanied by an expansion of high-temperature *** ongoing greening efforts,rapid urbanization poses a threat to these green *** in the normalized difference built-up index(NDBI)and land use transfer(LDT)were identified as the primary drivers of urban LST *** integrating geographic detector technology and artificial neural network models,we optimized the selection of input factors in the prediction model and used it to explore the future changes in LST in *** average LST in Yakutsk is expected to reach 23.4℃ and 25.1℃ in 2030 and 2040,respectively,with a further increase in high-temperature *** study provides a reference for ecological,hydrological,and geological assessments of cities in permafrost regions.

关键词： Remote sensing Land surface temperature Land use/Land cover Permafrost Yakutsk

Photoredox-Catalyzed Metal-Free Regio-&Stereoselective C(sp^(2))-H Amination of Enamides with N-Aminopyridium Salts

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Chinese Journal of Chemistry 2024年第18期42卷 2235-2242页

作者： Zheng-Bao Qin Kun Ni Li Wang Xiao-Di Wu Yu Zhang kai Zhao Institute of Advanced Synthesis School of Chemistry and Molecular EngineeringJiangsu National Synergetic Innovation Center for Advanced MaterialsNanjing Tech UniversityNanjingJiangsu211816China college of Chemical Engineering Nanjing Forestry UniversityNanjingJiangsu 210037China

A visible-light-induced photoredox-catalyzed regioselective and stereoselective C(sp')-H amination of enamides with bench-stable and A visible-light-induced photoredox-catalyzed regioselective and stereoselective C(sp)-H amination of enamides with bench-stable and easily accessible N-aminopyridium salts is developed,affording synthetically and biologically prominent vicinal 1,2-diamine scaffolds with broad substrate scope and excellent functional group *** transformation proceeded through a radical pathway involving the Giese addition of the relatively electrophilic N-centered sulfonamidyl radical species to nucleophilicβ-olefinic position of enamides followed by the ensuing single electron oxidation andβ-H elimination,delivering geometrically-defined Z-configuredβ-sulfonamidylated *** operational simplicity,environmental friendliness and cost efficiency of this methodology allowed it to pave a new avenue to enrich the arsenal of synthetically crucial functionalized enamides and their related derivatives.

关键词： Enamides Amination Photoredox catalysis Regioselective Stereoselective Metal-free

Electronic and Thermoelectric Properties in SnS-Nanoribbon-Based Heterojunctions

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Chinese Physics Letters 2024年第9期41卷 63-68页

作者： kai-Bo Zhang Shi-Hua Tan Xiao-Fang Peng Meng-Qiu Long Hunan Province Key Laboratory of Materials Surface or Interface Science and Technology Central South University of Forestry and TechnologyChangsha 410004China School of Physics and Electronics Central South UniversityChangsha 410083China

As an earth-abundant and environmentally friendly material,tin sulfide(SnS)is not only a high-performance photovoltaic material,but also a new promising thermoelectric *** extensive research on the thermoelectric properties of this material in recent years,the room-temperature thermoelectric figure of merit(ZT)of SnS has not been broke through 2[2022 *** Mater.651143].In this work,based on a combination of density functional theory and non-equilibrium Green’s function method,the electronic and thermoelectric properties in SnS-nanoribbon-based heterojunctions are *** results show that although SnS nanoribbons(SNSNRs)with zigzag edges(ZSNSNRs)and armchair edges(ASNSNRs)both have semiconductor properties,the bandgaps of ASNSNRs are much wider than those of ZSNSNRs,which induces much wider conductance gaps of𝑁-ASNSNR(N𝑁is the number of tin-sulfide lines across the ribbon width)).In the positive energy region,the ZT peaks of𝐿L-SNS-Au are much larger than those of𝐿L-SNS-GNR(L𝐿represents the number of longitudinal repeating units of SNSNR in the scattering region).While in the positive energy region,the ZT peaks of𝐿-SNSGNR are larger than those of𝐿-*** calculations reveal that the figure of merit will be over 3.7 in L-SNS-Au and 2.2 in𝐿L-SNS-GNR at room temperature,and over 4 in𝐿L-SNS-Au and 2.6 in𝐿L-SNS-GNR at 500 K.

关键词： material. sulfide ribbon

Nitrogen addition increased resistance of resident plant community to Solidago canadensis invasion by altering allelopathic effect

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Journal of Plant Ecology 2024年第2期17卷 110-121页

作者： Jing-Fang Cai kai Sun Lin Li Si-Ha A Yi-Luan Shen Hong-Li Li School of Ecology and Nature Conservation Beijing Forestry UniversityBeijing 100083China The Key Laboratory of EcologicalProtection in the Yellow River Basin of National forestry and Grassland Administration Beijing Forestry UniversityBeijing 100083China

Allelopathy plays an important role in the interaction between invasive and resident *** nitrogen(N)deposition has become a global problem,but it is unclear whether N enrichment affects the interaction between invasive and resident plants by affecting their ***,we performed a greenhouse experiment in which the resident plant community was grown under two levels of invasion by ***(invasion *** invasion)and fully crossed with two levels of allelopathy(with or without adding activated carbon)and two levels of N addition(with or without).The resident plant communities were constructed with eight herbaceous species that often co-occur with *** results showed that both allelopathy of *** and the resident plants had obvious positive effects on their own *** addition had more obvious positive effects on the resident plants under invasion than those that were not ***,N addition also altered the allelopathy of resident ***,N addition improved the allelopathy of resident plants when they were invaded but decreased the allelopathy of resident plants when they grew *** nitrogen addition had no obvious effect on ***,it reduced the allelopathy of *** results suggest that N addition could improve the resistance of resident plants to invasion by improving the allelopathy of resident plants and reducing the allelopathy of *** fndings provide a scientifc basis to manage and control the *** invasion.

关键词： allelochemicals biological invasion nutrient input nitrogen addition resident plants Solidago canadensis

Grouping tree species to estimate basal area increment in temperate multispecies forests in Durango,Mexico

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Forest Ecosystems 2024年第1期11卷 1-13页

作者： Jaime Roberto Padilla-Martínez Carola Paul kai Husmann Jose Javier Corral-Rivas Klaus von Gadow Department of Forest Economics and Sustainable Land-use Planning Faculty of Forest Sciences and Forest EcologyUniversity of GottingenBüsgenweg 137077GottingenGermany Facultad de Ciencias Forestales Universidad Juarez del Estado de DurangoRío Papaloapan y Boulevard Durango S/N34120DurangoMexico Faculty of forestry and Forest Ecology Georg-August-UniversitatBüsgenweg 537077GottingenGermany Department of forestry and Wood Science Faculty of AgriSciencesStellenbosch UniversityStellenbosch Private Bag X1Stellenbosch7602South Africa

Multispecies forests have received increased scientific attention,driven by the hypothesis that biodiversity improves ecological ***,a greater species diversity presents challenges for forest management and *** study aims to develop basal area growth models for tree species *** analysis is based on a dataset of 423 permanent plots(2,500 m^(2))located in temperate forests in Durango,***,we define tree species cohorts based on individual and neighborhood-based variables using a combination of principal component and cluster ***,we estimate the basal area increment of each cohort through the generalized additive model to describe the effect of tree size,competition,stand density and site *** principal component and cluster analyses assign a total of 37 tree species to eight cohorts that differed primarily with regard to the distribution of tree size and vertical position within the *** generalized additive models provide satisfactory estimates of tree growth for the species cohorts,explaining between 19 and 53 percent of the total variation of basal area increment,and highlight the following results:i)most cohorts show a"rise-and-fall"effect of tree size on tree growth;ii)surprisingly,the competition index"basal area of larger trees"had showed a positive effect in four of the eight cohorts;iii)stand density had a negative effect on basal area increment,though the effect was minor in medium-and high-density stands,and iv)basal area growth was positively correlated with site quality except for an oak *** developed species cohorts and growth models provide insight into their particular ecological features and growth patterns that may support the development of sustainable management strategies for temperate multispecies forests.

关键词： Temperate multispecies forests Cluster analysis Basal area increment Generalized additive models

Metal-Free Electrochemical Trifluoromethylation of Imidazole-Fused Heterocycles with Trifluoromethyl Thianthrenium Triflate

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Chinese Journal of Chemistry 2024年第15期42卷 1679-1685页

作者： Chang Ge Lipeng Qiao Yuyang Zhang kai Sun jangzhen An Mei Peng Xiaolan Chen Lingbo Qu Bing Yu College of Chemistry Zhengzhou UniversityZhengzhouHenan 450001China National Engineering Research Center of Low-Carbon Processing and Utilization of Forest Biomass Nanjing Forestry UniversityNanjingJiangsu210037China School of Pharmacy Hengyang Medical SchoolUniversity of South ChinaHengyangHunan 421001China

A novel and eco-friendly electrochemical activation of trifluoromethyl thianthrenium triflate(TT-CF_(3)^(+)OTf^(-))for trifluoromethylation of imidazole-fused heteroaromatic compounds was *** method involves the direct electrolysis of TT-CF_(3)^(+)OTf^(-)without the requirement of external oxidants or catalysts,aligning with the principles of green chemistry.A wide range of imidazole-fused heteroaromatic compounds including imidazo[1,2-a]pyridines and benzo[d]imidazo[2,1-b]thiazoles have been successfully trifluoromethylated using this technique,exhibiting excellent compatibility with various functional groups and a broad substrate ***,the method's applicability for one-pot sequential reactions enables the reduction of waste and resource consumption by eliminating the need for intermediate purification steps.

关键词： Trifluoromethylation Electrochemical Metal-free Imidazole-fused heterocycles Thianthrenium

基于改进遥感生态指数的青藏公路那(曲)安(多)段生态环境评估及驱动机制分析

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环境科学 2024年第3期45卷 1586-1597页

作者：傅楷翔贾国栋余新晓王旭北京林业大学水土保持学院北京100083 北京林业大学水土保持国家林业和草原局重点实验室北京100083

青藏公路沿线生态环境是西藏地区生态文明建设的重要组成部分,目前研究青藏高原独特的地理环境普遍存在数据获取困难、时效性过低及未考虑研究区独特的“高寒盐碱”环境状况等问题.基于GEE平台及研究区独特地理环境,对遥感生态指数(RSEI... 详细信息

青藏公路沿线生态环境是西藏地区生态文明建设的重要组成部分,目前研究青藏高原独特的地理环境普遍存在数据获取困难、时效性过低及未考虑研究区独特的“高寒盐碱”环境状况等问题.基于GEE平台及研究区独特地理环境,对遥感生态指数(RSEI)进行改进,采用主成分分析法构建一种新的适用于高寒盐碱地区的盐碱遥感生态指数(SRSEI)作为生态环境质量评价指标,利用Arc GIS 10.3平台、地理探测器等方法在多时空尺度下分析青藏公路那曲至安多段沿线生态环境质量空间分布格局与时间变异趋势,并探究自然和人为等8个控制因子对SRSEI时空变化的驱动机制.结果表明:(1)相较于RSEI,SRSEI对植被更加敏感,对植被稀疏和盐碱化严重地区的分辨能力更强,适合高寒盐碱区生态质量评价.(2)研究区生态环境质量空间尺度上存在明显的地理分异性,生态质量较差的区域主要集中在北部安多县城,质量等级为优和良地区主要分布在中西部和东南部那曲地区;时间尺度上32年间研究区生态环境整体呈改善趋势,中西部和东南部植被覆盖度明显增加,对生态环境有很强的改善作用,改善面积1 425.98 km^(2),占比99.82%.SRSEI均值为0.49,总体呈波动上升趋势,平均增幅为0.015 7 a^(-1).(3)土地利用方式是研究区生态环境质量变化中驱动力最大的影响因子,多年份平均q值0.1576,环境因子的影响力较低;多因子交互结果显示,研究区的生态环境现状是多重因素共同作用的结果,所有因子在交互作用下均有协同增强的作用,且人为因素的影响力在逐步上升,植被净初级生产力(NPP)和土地利用方式交互作用是研究区生态环境质量的主要交互控制因子.该研究可为那曲至安多段沿线生态环境保护和可持续发展提供理论依据.

关键词：生态环境质量遥感生态指数(RSEI) 地理探测器 GEE平台青藏公路沿线

Reducing Operation Emissions and Improving Work Efficiency Using a Pure Electric Wheel Drive Tractor

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Engineering 2024年第6期37卷 230-245页

作者： Chang-kai Wen Wen Ren Qing-Zhen Zhu Chun-Jiang Zhao Zhen-Hao Luo Sheng-Li Zhang Bin Xie Zhi-Jun Meng Research Center of Intelligent Equipment Beijing Academy of Agriculture and Forestry SciencesBeijing 100097China State Key Laboratory of Intelligent Agricultural Power Equipment Beijing 100097China BYD Company Limited Shenzhen 518118China College of Agricultural Engineering Jiangsu UniversityZhenjiang 212013China College of Engineering China Agricultural UniversityBeijing 100083China

In response to the problems of excessive greenhouse-gas and particulate emissions and the low traction efficiency of conventional diesel tractors in the field,a purely electric wheel-side drive tractor was studied,including an electric motor drive system,a battery ballast system,and an electro–hydraulic suspension *** paper develops a dynamics model of an electric tractor-ploughing unit under complex soil conditions,leading to the proposal of an active control method for drive wheel torque and a joint control method for the traction force of the suspension system and the front-and rear-axle loads of a ***,the tractor is prototyped and assembled,and ploughing tests are carried *** ploughing results show that the active torque-distribution control method proposed in this study reduces the tractor slip by 14.83%and increases the traction efficiency by 10.28%compared with the average torquedistribution *** with the conventional traction control mode,the joint control method for traction and ballast proposed in this paper results in a 3.7%increase in traction efficiency,a 15.05%decrease in slip,and a 4.9%reduction in total drive motor energy *** study will help to improve the operation quality and traction efficiency of electric tractors in complex soil conditions.

关键词： Electric tractor Ploughing unit Torque distribution Active ballast Traction performance

Constructing osteo-inductive bio-ink for 3D printing through hybridization of gelatin with maleic acid modified bacterial cellulose by regulating addition volumes of maleic acid solution

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Journal of Bioresources and Bioproducts 2024年第3期9卷 336-350页

作者： Xucai Wang Dengxian Wu Wei Liao Yaxuan Liu Wenhui Pei Jixian Wang Jiayu Gu Peng Wang kai Lan Caoxing Huang Co-Innovation Center for Efficient Processing and Utilization of Forest Resources College of Chemical EngineeringNanjing Forestry UniversityNanjing 210037China State Key Laboratory of Pharmaceutical Biotechnology Department of Sports Medicine and Adult Reconstructive SurgeryNanjing Drum Tower Hospitalthe Affiliated Hospital of Nanjing University Medical SchoolNahanjing 210008China Children's Hospital of Nanjing Medical university Nanjing 210008China Jiangsu Institute of Metrology Nanjing 210023China Department of Forest Biomaterials College of Natural ResourcesNorth Carolina State UniversityRaleigh NC 27695USA

Bacterial cellulose(BC)is an exopolysaccharide with unique properties that has been applied in various ***,the dense and intertwined nature of BC fibers limits its use in certain applications,including 3D printing scaffolds for bone *** this work,a controllable BC-based bio-ink for 3D printing was successfully prepared by modifying the neat BC through maleic acid(MA)treatment,aiming to promote bone tissue *** achieve homogeneous BC dispersions while preserving its crystalline and chemical properties,BC was modified by MA solution(60%,w/V)with solid-liquid ratio from 1꞉5 to 1꞉50(w/V)to obtain MA-BC *** analysis results from microstructure,chemical group,crystallinity,and wettability indicated that the BC/MA solution with ratio of 1꞉30 demonstrated the best pre-treatment performance to obtain ***,by combining MA-BC with gelatin,we successfully formulated MA-BC-GEL gels with favorable rheological properties and compression modulus,which can be used as promising bio-inks for 3D bioprinting *** vitro tests demonstrated 1꞉30 MA-BC possessed excellent biocompatibility,a significant ability to express the alkaline phosphatase gene and osteogenic-related genes,and facilitated the formation of mineralized *** utilization of this novel bio-ink in scaffold preparation for bone regeneration highlights the promising application of modified BC in bone tissue engineering field.

关键词： Bacterial cellulose Maleic acid Osteogenic activity Printability