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A new euphane triterpenoid from the aerial parts of Garuga forrestii

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A new euphane triterpenoid from the aerial parts of Garuga f...

Effects of aggregate size distribution and carbon nanotubes on the mechanical properties of cemented gangue backfill samples under true triaxial compression

中国化学会第十届全国天然有机化学学术会议

作者： shuai-wen yin Wei Wang Ning Ma Qiang Lai Tian-Xiang Li Li-Cheng Zhu School of life sciences Jinggangshan University

A new euphane triterpenoid, namely, 13α,14β,17α-lanosta-7,24-diene-1β,3α-diol(1), were isolated from the aerial parts of Garuga forrestii. The structure of the compound was elucidated on the basis of spectral evi... 详细信息

关键词： Garuga forrestii chemical constituent triterpenoid

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International Journal of Minerals,Metallurgy and Materials 2025年第2期32卷 311-324页

作者： Qian yin Fan wen Zhigang Tao Hai Pu Tianci Deng Yaoyao Meng Qingbin Meng Hongwen Jing Bo Meng Jiangyu Wu State Key Laboratory of Intelligent Construction and Healthy Operation and Maintenance of Deep Underground Engineering China University of Mining and TechnologyXuzhou 221116China State Key Laboratory of Mining Response and Disaster Prevention and Control in Deep Coal Mines Anhui University of Science and TechnologyHuainan 232001China State Key Laboratory for Geomechanics&Deep Underground Engineering China University of Mining and Technology(Beijing)Beijing 100083China Key Laboratory of Xinjiang Coal Resources Green Mining Ministry of EducationXinjiang Institute of EngineeringUrumqi 830023China

The mechanical behavior of cemented gangue backfill materials(CGBMs)is closely related to particle size distribution(PSD)of aggregates and properties of cementitious ***,the true triaxial compression tests,CT scanning,SEM,and EDS tests were conducted on cemented gangue backfill samples(CGBSs)with various carbon nanotube concentrations(P_(CNT))that satisfied fractal theory for the PSD of *** mechanical properties,energy dissipations,and failure mechanisms of the CGBSs under true triaxial compression were systematically *** results indicate that appropriate carbon nanotubes(CNTs)effectively enhance the mechanical properties and energy dissipations of CGBSs through micropore filling and microcrack bridging,and the optimal effect appears at P_(CNT)of 0.08wt%.Taking PSD fractal dimension(D)of 2.500 as an example,compared to that of CGBS without CNT,the peak strength(σ_(p)),axial peak strain(ε_(1,p)),elastic strain energy(Ue),and dissipated energy(U_(d))increased by 12.76%,29.60%,19.05%,and90.39%,***,excessive CNTs can reduce the mechanical properties of CGBSs due to CNT agglomeration,manifesting a decrease inρ_(p),ε_(1,p),and the volumetric strain increment(Δε_(v))when P_(CNT)increases from 0.08wt%to 0.12wt%.Moreover,the addition of CNTs improved the integrity of CGBS after macroscopic failure,and crack extension in CGBSs appeared in two modes:detour and pass through the ***σ_(p)and U_(d)firstly increase and then decrease with increasing D,and porosity shows the opposite ***ε_(1,p)andΔε_(v)are negatively correlated with D,and CGBS with D=2.150 has the maximum deformation parameters(ε_(1,p)=0.05079,Δε_(v)=0.01990)due to the frictional slip effect caused by coarse *** increasing D,the failure modes of CGBSs are sequentially manifested as oblique shear failure,"Y-shaped"shear failure,and conjugate shear failure.

关键词： cemented gangue backfill materials particle size distribution true triaxial compression test carbon nanotubes mechanical properties failure modes

Ultrathin nanoporous metal electrodes facilitate high proton conduction for low-Pt PEMFCs

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Nano Research 2021年第8期14卷 2681-2688页

作者： shuai Shi Xianglong wen Qinqin Sang shuai yin Kaili Wang Jian Zhang Min Hu Huiming yin Jia He Yi Ding Tianjin Key Laboratory of Advanced Functional Porous Materials Institute for New Energy Materials&Low-Carbon TechnologiesSchool oj Materials Science and EngineeringTianjin University of TechnologyTianjin 300384China

Design of catalyst layers(CLs)with high proton conductivity in membrane electrode assemblies(MEAs)is an important issue for proton exchange membrane fuel cells(PEMFCs).Herein,an ultrathin catalyst layer was constructed based on Pt-decorated nanoporous gold(NPG-Pt)with sub-Debye-length thickness for proton *** the absence of ionomer incorporation in the CLs,these integrated carbon-free electrodes can deliver maximum mass-specific power density of 198.21 and 25.91 kW·gPt^(-1) when serving individually as the anode and cathode,at a Pt loading of 5.6 and 22.0 pg·cm^(-2),respectively,comparable to the best reported nano-catalysts for ***-depth quantitative experimental measurements and finite-element analyses indicate that improved proton conduction plays a critical role in activation,ohmic and mass transfer polarizations.

关键词： nanoporous metal electrode proton exchange membrane fuel cell(PEMFC) ultrathin catalyst layer proton conduction dealloying

Decay rate of Larix gmelinii coarse woody debris on burned patches in the Greater Khingan Mountains

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Journal of Forestry Research 2021年第6期32卷 2349-2363页

作者： Shubo Huang Lixiang wen shuai yin Meng Guo Fangbing Yu Key Laboratory of Geographical Processes and Ecological Security in Changbai Mountains School of Geographical SciencesNortheast Normal UniversityMinistry of EducationChangchun130024People’s Republic of China Center for Global Environmental Research National Institute for Environmental StudiesTsukuba3058506Japan

The decomposition of coarse woody debris(CWD)affects the energy flow and nutrient cycling in forest *** studies on CWD have focused on the input,decomposition,reserve dynamics,and CWD functions,but coarse woody debris decomposition is complex and the results from different regions vary *** is not clear which factors affect decay rate(k),especially at different decomposition *** this study,a single-exponential decay model was used to analyze the characteristics of CWD decomposition in Larix gmelinii forests over the 33 years following a fire in the Greater Khingan *** results show that the decay rate of coarse woody debris was positively correlated to decay *** average decomposition rate was 0.019,and 41 years and 176 years are needed for a 50%and 95%mass loss,*** nutrient content,density,and water content could explain the variance in the decay rate(~42%)of the decay factors such as amount of leaching,degree of fragmentation,respiration of the debris,and biotransformation,and varied significantly between different decay *** the space-time substitution method,this study arranged the coarse woody debris of different mortality times to form a 33 year chronosequence which revealed the decomposition *** was concluded that the decay rate was mainly explained by structural component of the debris and its nitrogen and water *** paper quantifies the indicators affecting CWD decay to explain the decomposition process.

关键词： Coarse woody debris Decay rate Space–time substitution Boreal forest Fire disturbance

Succession of Denitrifying Community Composition in Coastal Wetland Soils Along a Salinity Gradient

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Pedosphere 2012年第3期22卷 367-374页

作者： PIAO Zhe ZHANG wen-wen MA shuai LI Yu-Min yin Shi-Xue Microbiology Section College of Environmental Science and EngineeringYangzhou UniversityYangzhou 225009(China)

To better understand the effect of salinity on denitrification communities, soils along a salinity gradient （ranging from 7.32 to 1.70 mS cm 1） in a wetland along the Yellow Sea coastline in Jiangsu Province, China, were studied using both culture-dependent and -independent methods. Culture efforts yielded 82 isolates in total, 81.7% of which were close relatives of Bacillus sp. based on partial sequences of their 16S rRNA genes. Denaturing gradient gel electrophoresis （DGGE） analysis based on 16S rRNA sequences suggested possible existence of bacterial community succession along the salinity gradient. Clone library analysis based on nosZ gene sequences （coding nitrous oxide reductase） showed that operational taxonomic units （OTUs） associated with α-proteobacteria dominated in all three soils, whereas those associated with β- and γ-subdivisions showed a clear succession. In the high salinity soil, only the OTUs associated with a-subdivision were found. In the medium salinity soil, small proportions of β- （6.5%） and γ-associated （19.6%） OTUs were found. In the low salinity soil, the proportions were further increased to 33% and 25% for β- and γ-Proteobacteria, respectively. Statistic analysis using Unifrac P test showed that nosZ-communities in different saline soils were significantly different from each other. It could be concluded that α-subdivision of nosZ-community tended to be sustained in high salinity environments whereas β and γ-subdivisions, especially the former, tended to be sustained in low salinity environments. Salinity was the key determinant of nosZ-community composition in the environment.

关键词： clone library denaturing gradient gel electrophoresis (DGGE) nosZ gene Yellow Sea coastline

A cellulose-based lithium-ion battery separator with regulated ionic transport and high thermal stability for extreme environments

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Nano Research 2025年第1期18卷 315-322页

作者： Kun-Peng Yang Song Xie Zi-Meng Han Hao-Cheng Liu Chong-Han yin wen-Bin Sun Zhang-Chi Ling Huai-Bin Yang De-Han Li Qing-Fang Guan Shu-Hong Yu Department of Chemistry New Cornerstone Science LaboratoryInstitute of Biomimetic Materials&ChemistryAnhui Engineering Laboratory of Biomimetic MaterialsDivision of Nanomaterials&ChemistryHefei National Research Center for Physical Sciences at the MicroscaleUniversity of Science and Technology of ChinaHefei 230026China Institute of Innovative Materials Department of Materials Science and EngineeringDepartment of ChemistrySouthern University of Science and TechnologyShenzhen 518055China

Separators play a critical role in lithium-ion ***,the restrictions of thermal stability and inferior electrical performance in commercial polyolefin separators significantly limit their applications under harsh ***,we report a cellulose-assisted self-assembly strategy to construct a cellulose-based separator massively and *** an ultrahigh ionic conductivity in electrolytes of 3.7 mS·cm^(-1) and the ability to regulate ion transport,the obtained separator is a promising alternative for high-performance lithium-ion *** addition,integrated with high thermal stability,the cellulose-based separator endows batteries with high safety at high temperatures,greatly expanding the application scenarios of energy storage devices in extreme environments.

关键词： lithium-ion batteries bio-inspired materials battery separators cellulose nanofiber ultrahigh ionic conductivity high safety

Vegetation Phenology in Permafrost Regions of Northeastern China Based on MODIS and Solar-induced Chlorophyll Fluorescence

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Chinese Geographical Science 2021年第3期31卷 459-473页

作者： wen Lixiang GUO Meng yin shuai HUANG Shubo LI Xingli YU Fangbing Key Laboratory of Geographical Processes and Ecological Security in Changbai Mountains Ministry of EducationSchool of Geographical SciencesNortheast Normal UniversityChangchun 130024China Centers for Global Environmental Research National Institute for Environmental StudiesTsukuba 305-8555Japan

Vegetation phenology is an indicator of vegetation response to natural environmental changes and is of great significance for the study of global climate change and its impact on terrestrial *** normalized difference vegetation index(NDVI)and enhanced vegetation index(EVI),extracted from the Moderate Resolution Imaging Spectrometer(MODIS),are widely used to monitor phenology by calculating land surface ***,the applicability of the vegetation index based on‘greenness'to monitor photosynthetic activity is hindered by poor observation conditions(e.g.,ground shadows,snow,and clouds).Recently,satellite measurements of solar-induced chlorophyll fluorescence(SIF)from OCO-2 sensors have shown great potential for studying vegetation ***,we tested the feasibility of SIF in extracting phenological metrics in permafrost regions of the northeastern China,exploring the characteristics of SIF in the study of vegetation phenology and the differences between NDVI and *** results show that NDVI has obvious SOS advance and EOS lag,and EVI is closer to *** growing season length based on SIF is often the shortest,while it can represent the true phenology of vegetation because it is closely related to *** is more sensitive than the traditional remote sensing indices in monitoring seasonal changes in vegetation phenology and can compensate for the shortcomings of traditional vegetation *** also used the time series data of MODIS NDVI and EVI to extract phenological metrics in different permafrost *** results show that the length of growing season of vegetation in predominantly continuous permafrost(zone I)is longer than in permafrost with isolated taliks(zone II).Our results have certain significance for understanding the response of ecosystems in cold regions to global climate change.

关键词： vegetation phenology permafrost Moderate Resolution Imaging Spectrometer(MODIS) solar-induced chlorophyll fluorescence(SIF) northeastern China

Efect of Al Content on the Corrosion Behavior of Extruded Dilute Mg–Al–Ca–Mn Alloy

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Acta Metallurgica Sinica(English Letters) 2023年第1期36卷 77-90页

作者： Bao‑Chang Liu shuai Zhang Hong‑Wei Xiong wen‑Hao Dai yin‑Long Ma College of Construction Engineering Jilin UniversityChangchun 130026China Key Laboratory of Drilling and Exploitation Technology in Complex Conditions of Ministry of Natural Resources Changchun 130026China

The microstructure,extrusion texture and corrosion behavior of extruded dilute Mg–Al–Ca–Mn alloy with diferent Al contents were *** corrosion rate of the alloy was more sensitive to the Fe *** 1.2 wt%Al showed the lowest corrosion rate,which was mainly attributed to the weakening of the cathode efect caused by the increase of the Al and the decrease of the Fe in the precipitated *** grains,stronger basal surface texture and higher corrosion potential deriving from the higher Al content of the matrix also further enhanced the corrosion resistance of the matrix.

关键词： Dilute magnesium alloys Corrosion behavior Al content Fe impurity Second phase

Finite Diffeomorphism Types of Four Dimensional Ricci Flow with Bounded Scalar Curvature

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Acta Mathematica Sinica,English Series 2021年第11期37卷 1751-1767页

作者： wen shuai JIANG School of Mathematical Sciences Zhejiang UniversityHangzhou 310027P.R.China

In this paper,we consider Ricci flow on four dimensional closed manifold with bounded scalar curvature,noncollasping volume and bounded *** such conditions,we can show that the manifold has finitely many diffeomorphism types,which generalizes Cheeger–Naber’s result to bounded scalar curvature along Ricci *** particular,this implies the manifold has uniform L^(2) Riemann curvature *** an application,we point out that four dimensional Ricci flow would not have uniform scalar curvature upper bound if the initial metric only satisfying lower Ricci curvature bound,lower volume bound and upper diameter bound.

关键词： Ricci flow scalar curvature