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Green Energy & Environment 2024年第3期9卷 544-555页

作者： Hengyuan Liu Xingjiang Wu Yuhao Geng Xin Li Jianhong Xu The State Key Laboratory of Chemical Engineering Department of Chemical EngineeringTsinghua UniversityBeijing100084China

Electrocatalytic nitrogen reduction reaction(NRR)is considered as a promising candidate to achieve ammonia synthesis because of clean electric energy,moderate reaction condition,safe operating process and harmless by-products.However,the chemical inertness of nitrogen and poor activated capacity on catalyst surface usually produce low ammonia yield and faradic efficiency.Herein,the microfluidic technology is proposed to efficiently fabricate enriched iridium nanodots/carbon architecture.Owing to in-situ co-precipitation reaction and microfluidic manipulation,the iridium nanodots/carbon nanomaterials possess small average size,uniform dispersion,high conductivity and abundant active sites,producing good proton activation and rapid electrons transmission and moderate adsorption/desorption capacity.As a result,the as-prepared iridium nanodots/carbon nanomaterials realize large ammonia yield of 28.73 μg h^(-1) cm^(-2) and faradic efficiency of 9.14%in KOH solution.Moreover,the high ammonia yield of 11.21 μg h^(-1) cm^(-2) and faradic efficiency of 24.30%are also achieved in H_(2)SO_(4) solution.The microfluidic method provides a reference for large-scale fabrication of nano-sized catalyst materials,which may accelerate the progress of electrocatalytic NRR in industrialization field.

关键词： Iridium nanodots carbon Microfluidic technology Efficient synthesis Electrocatalytic nitrogen fixation

MIL-100(V) derived porous vanadium oxide/carbon microspheres with oxygen defects and intercalated water molecules as high-performance cathode for aqueous zinc ion battery

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Journal of Energy Chemistry 2024年第3期90卷 578-589,I0013页

作者： Yuexin Liu Jian Huang Xiaoyu Li Jiajia Li Jinhu Yang Kefeng Cai Shanghai Key Laboratory of Development and Application for Metal-Functional Materials Key Laboratory of Advanced Civil Engineering MaterialsMinistry of EducationSchool of Materials Science&EngineeringTongji UniversityShanghai 201804China State Key Laboratory of High Performance Ceramics and Superfine Microstructure Shanghai Institute of CeramicsChinese Academy of SciencesShanghai 201800China Research Center for Translational Medicine East HospitalTongji University School of MedicineShanghai 200092China

The development of aqueous zinc ion battery cathode materials with high capacity and high magnification is still a challenge.Herein,porous vanadium oxide/carbon(p-VO_(x)@C,mainly VO_(2) with a small amount of V_(2)O_(3)) core/shell microspheres with oxygen vacancies are facilely fabricated by using a vanadium-based metal-organic framework(MIL-100(V)) as a sacrificial template.This unique structure can improve the conductivity of the VO_(x),accelerate electrolyte diffusion,and suppress structural collapse during circulation.Subsequently,H_(2)O molecules are introduced into the interlayer of VO_(x) through a highly efficient in-situ electrochemical activation process,facilitating the intercalation and diffusion of zinc ions.After the activation,an optimal sample exhibits a high specific capacity of 464.3 mA h g^(-1) at0.2 A g^(-1) and 395.2 mA h g^(-1) at 10 A g^(-1),indicating excellent rate performance.Moreover,the optimal sample maintains a capacity retention of about 89.3% after 2500 cycles at 10 A g^(-1).Density functional theory calculation demonstrates that the presence of oxygen vacancies and intercalated water molecules can significantly reduce the diffusion barrier for zinc ions.In addition,it is proved that the storage of zinc ions in the cathode is achieved by reversible intercalation/extraction during the charge and discharge process through various ex-situ analysis technologies.This work demonstrates that the p-VO_(x)@C has great potential for applications in aqueous ZIBs after electrochemical activation.

关键词： Metal-organic frameworks Vanadium oxide carbon Zn-ion batteries Electrochemical activation

Going deep:Roots,carbon,and analyzing subsoil carbon dynamics

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Molecular Plant 2024年第1期17卷 1-3页

作者： Ezhilmathi Angela Joseph Fernando Michael Selvaraj Yusaku Uga Wolfgang Busch Hunt Bowers Joe Tohme Alliance of Bioversity International and CIAT Km 17 Recta Cali-PalmiraAprtado Aereo 6713Cali 763537Colombia National Institute of Agrobiological Sciences(NIAS) TsukubaIbaraki 305-0856Japan Salk Institute for Biological Studies 10010 N Torrey Pines RoadLa JollaCA 92037USA Earth Optics Suite 840ArlingtonVA 22202USA

Agricultural practices currently contribute to the emission of approximately 10%–12%atmospheric greenhouse gasses,with tillage agriculture accelerating soil disruption and carbon dioxide release.Nevertheless,various options exist,such as converting new lands for agriculture,promoting healthier plant-based diets,adopting advanced management technologies,and minimizing food loss.However,these measures alone are insufficient to ensure environmental sustainability within planetary boundaries.

关键词： soil measures carbon

Uncovering the largest negative carbon isotope excursion in Earth history

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Science China Earth Sciences 2024年第3期67卷 885-889页

作者： Chao LI Haiyang WANG State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Chengdu University of TechnologyChengdu 610059China Institute of Sedimentary Geology Chengdu University of TechnologyChengdu 610059China Key Laboratory of Deep-time Geography and Environment Reconstruction and Applications of Ministry of Natural Resources Chengdu University of TechnologyChengdu 610059China International Center for Sedimentary Geochemistry and Biogeochemistry Research Chengdu University of TechnologyChengdu 610059China State Key Laboratory of Biogeology and Environmental Geology China University of GeosciencesWuhan 430074China

The carbon cycle plays a pivotal role in regulating Earth’s surface environment through atmospheric-oceanic acid-base and redox processes, functioning as the engine driving the evolution of our planet’s surface. A deep understanding of the carbon cycle’s evolution is thus essential for our understanding of the evolution of our planet’s habitability.

关键词： carbon planet evolution

Correlation and Pathway Analysis of the carbon,Nitrogen,and Phosphorus in Soil-Microorganism-Plant with Main Quality Components of Tea(Camellia sinensis)

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Phyton-International Journal of Experimental Botany 2024年第3期93卷 487-502页

作者： Chun Mao Ji He Xuefeng Wen Yangzhou Xiang Jihong Feng Yingge Shu College of Agriculture Guizhou UniversityGuiyangChina School of Geography and Resources Guizhou Education UniversityGuiyangChina

The contents of carbon(C),nitrogen(N),and phosphorus(P)in soil-microorganisms-plant signiﬁcantly affect tea quality by altering the main quality components of tea,such as tea polyphenols,amino acids,and caffeine.However,few studies have quantiﬁed the effects of these factors on the main quality components of tea.The study aimed to explore the interactions of C,N,and P in soil-microorganisms-plants and the effects of these factors on the main quality components of tea by using the path analysis method.The results indicated that(1)The contents of C,N,and P in soil,microorganisms,and tea plants were highly correlated and collinear,and showed signiﬁcant correlations with the main quality components of tea.(2)Optimal regression equations were established to esti-mate tea polyphenol,amino acid,catechin,caffeine,and water extract content based on C,N,and P contents in soil,microorganisms,and tea plants(R^(2)=0.923,0.726,0.954,0.848,and 0.883,respectively).(3)Pathway analysis showed that microbial biomass phosphorus(MBP),root phosphorus,branch nitrogen,and microbial biomass carbon(MBC)were the largest direct impact factors on tea polyphenol,catechin,water extracts,amino acid,and caffeine content,respectively.Leaf carbon,root phosphorus,and leaf nitrogen were the largest indirect impact factors on tea polyphenol,catechin,and water extract content,respectively.Leaf carbon indirectly affected tea polyphenol content mainly by altering MBP content.Root phosphorus indirectly affected catechin content mainly by altering soil organic carbon content.Leaf nitrogen indirectly affected water extract content mainly by altering branch nitrogen content.The research results provide the scientiﬁc basis for reasonable fertilization in tea gardens and tea quality improvement.

关键词： Soil-microorganisms-plant system carbon nitrogen phosphorus tea quality path analysis

Flora, Structure and carbon Sequestration of Vegetation in the Southeast of the Mono Biosphere Reserve in Togo Amidst Environmental Challenges

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Open Journal of Forestry 2024年第2期14卷 155-181页

作者： Gbétey Kokouvi Akpamou Kossi Adjossou Hodabalo Egbelou Komlanvi Katche Akoete Kossi Hounkpati Kouami Kokou Faculty of Science-Forest Research Laboratory (FRL) University of Lome Lome Togo Ministry of the Environment and Forest Resources Lom&#233 Togo National Agricultural Training Institute (INFA) of Tove Kpalime Togo

In most Sub-Saharan African countries such as Togo, people’s heavy dependence on ecosystem services is a major factor in accelerating the degradation of natural resources, which are already suffering as a result of climatic factors. This study was initiated to contribute to the sustainable and rational management of forest resources in the south-east of the Mono Biosphere Reserve in Togo. It specifically aims to identify and characterize the flora of the residual forest ecosystems within the reserve through their specific diversity, demographic structure, and carbon sequestration potential. The study was carried out in the forest ecosystems of Avévé. The methodology used was based on the analysis of phytosociological, forestry, ecological, and regeneration inventory data. Overall, the study revealed that the RBMT still has floristically viable habitats, despite the anthropogenic pressures it is subject to revealed a floristic diversity of 160 plant species divided into 52 families and 135 genera. The most represented families are Rubiaceae (29.09%), followed by Fabaceae (27.94%). The most represented species are Mitragyna inermis (Willd.) Kuntze (24.38%), Lecaniodiscus cupanioides Planch. Ex Benth (X) and Lonchocarpus sericeus (Poir.) Kunth (10.93%). The high presence of Mitragyna inermis observed in all the ecological groups identified makes it the characteristic species of the flooded marshy areas of southeast Togo and contributes to the resilience of the ecosystems and populations in the study area. The Shannon index for the formation groups varies between (3.03 and 5.16) bits. Pielou’s equitability varies between (0.43 and 0.63) bits. The overall average density is estimated at 210 stems/ha, with an average diameter of 25.57 ± 21.77 m and an average height of 7.93 ± 3.83 m. The adjustment of the diameter classes of the plant groups to the Weibull distribution gave an “inverted J” shape with coefficient values of less than 1 overall, reflecting the existence of multispecific or uneven-aged stands. Assessment o

关键词： Biodiversity Demographic Structure carbon Biosphere Reserve Forest Patches Togo

Contrasting compositions of PM_(2.5)in Northern Thailand during La Nina(2017)and El Nino(2019)years

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Journal of Environmental Sciences 2024年第1期135卷 585-599页

作者： Pavidarin Kraisitnitikul Duangduean Thepnuan Sarana Chansuebsri Nuttipon Yabueng Wan Wiriya Supattarachai Saksakulkrai Zongbo Shi Somporn Chantara Environmental Science Research Center Faculty of ScienceChiang Mai UniversityChiang Mai50200Thailand Department of Chemistry Faculty of Science and TechnologyChiang Mai Rajabhat UniversityChiang Mai50300Thailand Chemistry Department Faculty of ScienceChiang Mai UniversityChiang Mai50200Thailand School of Geography Earth and Environmental SciencesUniversity of BirminghamBirminghamB152TTUK

There have been a very limited number of systematic studies on PM_(2.5)compositions and their source contribution in Southeast Asia.This study aims to explore the characteristics of PM_(2.5)composition collected in Chiang Mai(Thailand)during La Nina and El Nino years and to apportion their sources during smoke haze and non-haze periods.The average PM_(2.5)concentration of smoke haze episode in 2019(El Nino)was much higher than in 2017(La Nina).The ratios of organic carbon(OC)to elemental carbon(EC),as well as K(biomass burning(BB)tracer)to PM_(2.5),were higher during smoke haze episodes in 2019 than in 2017 indicating a significant influence from BB.The ratios of secondary organic carbon(SOC)levels to primary organic carbon(POC)levels during smoke haze episodes were higher than those in non-haze period,which indicated greater SOC contributions or more photo-oxidation of precursors in haze episodes with high ambient temperatures.However,the ratios of soil markers(Ca and Mg)during non-haze period were high implying that soil source contributed more to PM_(2.5)concentrations when there less BB occurred.The positive Matrix Factorization(PMF)model revealed that the source of BB,characterized by high K fractions,was the largest contributor during smoke haze episodes accounting for 50%(2017)and 79%(2019).Climate conditions influence meteorological patterns,particularly during incidences of extreme weather such as droughts,which affect the scale and frequency of open burning and thus air pollution levels.

关键词： Climate Air pollution Metals carbon Biomass burning Source identification

Review of tribological properties of nanoparticle-based lubricants and their hybrids and composites

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Friction 2024年第4期12卷 569-590页

作者： Ye Zar Ni HTWE Aws.S.AL-JANABI Yasmin WADZER Hussin MAMAT Ku NOORYASMIN School of Materials&Mineral Resources Engineering Universiti Sains Malaysia(Engineering Campus)Nibong Tebal 14300Malaysia School of Aerospace Engineering Universiti Sains Malaysia(Engineering Campus)Nibong Tebal 14300Malaysia Universiti Sains Malaysia

Due to their encouraging results,nanolubricants have been revolutionary in the field of lubrication.The degree,to which the new material may improve the tribology,energy savings,and durability,is a crucial consideration for any new additive to a conventional lubricant.The results of the earlier research on carbon,metal,metal oxide,and their composites and hybrid nanolubricants as well as their effects on tribology,are summarized in this review paper.The most popular measuring methodologies,the tribology results for lubricants with an oil base,biodegradable base,and a water base,as well as the reasons that explain these tribological advancements,are all included in this study.Finally,prospects for more study in this area are emphasized.

关键词： nanolubricants tribology carbon metal metal oxide hybrid

Origin of the Dashuigou independent tellurium deposit at Qinghai–Xizang Plateau: constraints from the light stable isotopes C, O, and H

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Acta Geochimica 2024年第2期43卷 385-398页

作者： Jianzhao Yin Yuhong Chao Haoyu Yin Hongyun Shi Shoupu Xiang Wuhan Institute of Technology Wuhan 430074China College of Earth Sciences Jilin UniversityChangchun 130061China Ganzhongnan Institute of Geology and Mineral Exploration Nanchang 330002China Guinea Westfi eld Mining Company-Sarlu Jinzhong 031300China Orient Resources Ltd. RichmondB.C.V7E 1M8Canada Silvercorp Metals Inc. Beijing 100027China

By studying the light isotopic compositions of carbon,oxygen,and hydrogen,combined with previous research results on the ore-forming source of the deposit,the authors try to uncover its metallogenic origin.The δ^(18)O and δ^(13)C isotope signatures of dolomite samples vary between 10.2 and 13.0‰,and between−7.2 and−5.2‰,respectively,implying that the carbon derives from the upper mantle.δD and δ^(18) O of quartz,biotite,and muscovite from diff erent ore veins of the deposit vary between−82 and−59‰,and between 11.6 and 12.4‰,respectively,implying that the metallogenic solutions are mainly magmatic.According to the relevant research results of many isotope geologists,the fractionation degree of hydrogen isotopes increases as the depth to the Earth’s core increases,and the more diff erentiated the hydrogen isotopes are,the lower their values will be.In other words,mantle-derived solutions can have extremely low hydrogen isotope values.This means that the δD‰ value−134 of the pyrrhotite sample numbered SD-34 in this article may indicate mantle-derived oreforming fl uid of the deposit.The formation of the Dashuigou tellurium deposit occurred between 91.71 and 80.19 Ma.

关键词： carbon oxygen and hydrogen isotopes Origin Independent tellurium deposit The Qinghai–Xizang Plateau

Layer-by-layer epitaxy growth of thickness-controllable two-dimensional tungsten disulfide

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Science China(Information Sciences) 2024年第5期67卷 302-310页

作者： Jieyuan LIANG Zixing ZOU Junwu LIANG Di WANG Biao WANG Anshi CHU Jiali YI Cheng ZHANG Lizhen FANG Tian ZHANG Huawei LIU Xiaoli ZHU Dong LI Anlian PAN Key Laboratory for Micro-Nano Physics and Technology of Hunan Province State Key Laboratory of Chemo/Biosensing and Chemometrics Hunan Institute of Optoelectronic IntegrationCollege of Materials Science and Engineering School of Physics and ElectronicsHunan University School of Electronic Information and Electrical Engineering Changsha University School of Physics and Telecommunication Engineering Yulin Normal University Units Semiconductor Technology Co. Ltd. School of Physics and Electronics Hunan Normal University

Bilayer transition metal dichalcogenides（TMDs） balance the high mobility of single layers with the high state density of multilayers and therefore have promising application prospects in high-performance electronics. However, the layer-controlled growth of 2D materials is still confronted with challenges such as poor repeatability between different labs and a limited understanding of the growth mechanism at the atomic scale. Herein, we report a new carbon-assisted chemical vapor deposition process that can realize the growth of WS2sheets with high yield, precise thickness controllability, and repeatability. We show that carbon can act as a reducing agent and catalyst that preferentially reacts with the WO3precursor to form intermediate WO3-xproducts with low-valence state W. The resulting oxycarbide gas has a low surface adsorption energy when deposited on the surface of as-grown WS2, which provides nucleation sites for the subsequent layer of WS2growth and leads to the vertical growth of WS2sheets. The growth mechanism is thoroughly investigated. Electrical transport measurements show that the produced bilayer WS2possesses a high carrier mobility(up to 58 cm2·V-1·s-1) and small subthreshold swing（estimated to be 148 mV/decade）,which are among the best reported results for TMDs produced using CVD.

关键词： WS$_2$ thickness-controlled growth chemical vapor deposition additive carbon