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贵州科学 1994年第3期 28-32+11页

作者： X.y.Wang y.P.Wang j.y.han L.L.Zeng P.S.Wang( Guizhou Academy of Sciences, Guiyang 550001 )

With the devcioprnent of economics and owing to certain factors of plants themselves,some ferns arc in a dangcrous situation. It is necessary to set up a fern section or fernaripm in Guizhou as a gene pool mainly for subtropical ferns, which can not be replaced by the hcrbariurn or natural preserve. A fern section in Guizhou Botanical Garden has been established, It’s composed of a 3-are fern garden,a grccnhouse and a shed. 300 taxa of rems and fern aUics from Guizhou and East, South,North east, and South west patts in China have bccn gathered in recent 5 years. Another 3-year project supported by the National Natural Science Foundation of China (NSFC) is carded on for morc fern introduction. It will be not only for thc conservation of the rare and/or endangered pteridophytes, but as a base for fern researching, teaching, scientific propagating and *** shows that Guiyang, the capital of’ Guizhou, is one of the ideal places for fern introduction and conscrvation in China.

关键词： fern section gene pool botanical garden Guizhou

Dynamic properties of low-density expandable polystyrene concrete materials

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Defence Technology(防务技术) 2025年第1期43卷 94-108页

作者： jue han Hualin Fan Army Engineering University of PLA Nanjing 210007China Research Center of Lightweight Structures and Intelligent Manufacturing State Key Laboratory of Mechanics and Control of Aerospace StructuresNanjing University of Aeronautics and AstronauticsNanjing 210016China Henan International joint Laboratory of Dynamics of Impact and Disaster of Engineering Structures Department of Civil EngineeringNanyang Institute of TechnologyNanyang 473004China

Expanded polystyrene(EPS)concrete,known for its environmental friendliness,energy absorption capacity,and low impedance,has significant potential application in the fields of wave absorption and vibration *** study designed and prepared EPS concrete materials with four levels of ***-static uniaxial compression and Split Hopkinson Pressure Bar(SHPB)impact tests were conducted to obtain stress-strain curves,elastic moduli,failure modes,energy absorptions,and strain rate effects of the EPS concrete under quasi-static and dynamic loading *** influences of density on various performance indicators were *** combining the Zhu-Wang-Tang(ZWT)constitutive model with a modified elastic-brittle model,a modified dynamic constitutive model was *** accuracy of the model was validated by the experimental *** results indicate that the addition of EPS particles enhances the ductility of the EPS *** EPS concrete has significant strain rate effect,which gets stronger as density *** modifiedconstitutive model accurately characterizes the dynamic stress-strain curves of the EPS concrete.

关键词： EPS concrete Impact behavior Constitutive model SHPB test

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Gene therapy for spinal muscular atrophy:perspectives on the possibility of optimizing SMN1 delivery to correct all neurological and systemic perturbations

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Neural Regeneration Research 2025年第7期20卷 2011-2012页

作者： Sharon j.Brown Rafael j.yáñez-Muñoz Heidi R.Fuller School of Pharmacy and Bioengineering Keele UniversityKeeleUK Wolfson Center for Inherited Neuromuscular Disease TORCH BuildingRJAH Orthopaedic HospitalOswestryUK *** Center of Gene and Cell TherapyDepartment of Biological SciencesSchool of Life Sciences and the EnvironmentRoyal Holloway University of LondonEghamUK

Spinal muscular atrophy(SMA)is a genetic condition that results in selective lower motor neuron loss with concomitant muscle weakness and *** genetic cause of SMA was understood in 1995 when loss or impairment of the survival motor neuron 1(SMN1)gene was identified as the main contributing factor(Lefebvre et al.,1995).This,in combination with the discovery that humans have a“back-up”gene,SMN2,which can produce low levels(approximately 10%)of the full-length functional SMN protein,has led to the generation of SMA-specific gene *** was traditionally classified according to age of symptom onset and developmental milestones achieved,with life expectancy and severity varying between ***,SMN2 copy number is used as a proxy for the prediction of disease severity,with higher SMN2 copy number typically being associated with reduced severity of SMA,although this relationship is not absolute:some individuals with low SMN2 copy number have less severe SMA phenotypes and vice ***,the etiology of SMA is further complicated by other factors,such as non-typical nucleotide variants and SMN2-independent modifiers of disease severity.

关键词： atrophy traditionally absolute

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Spatial differentiation of carbon emissions from energy consumption based on machine learning algorithm:A case study during 2015–2020 in Shaanxi,China

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journal of Environmental Sciences 2025年第3期149卷 358-373页

作者： Hongye Cao Ling han Ming Liu Liangzhi Li China jikan Research Institute of Engineering Investigations and Design Co.Ltd.Xi’an 710043China College of Geological Engineering and Geomatics Chang’an UniversityXi’an 710061China School of Land Engineering Chang’an UniversityXi’an 710064China Xi’an Key Laboratory of Territorial Spatial Information School of Land EngineeringChang’an UniversityXi’an 710064China Department of Geography and Environmental Management University of WaterlooWaterlooOntario N2L 3G1Canada

Carbon emissions resulting from energy consumption have become a pressing issue for governments *** estimation of carbon emissions using satellite remote sensing data has become a crucial research *** studies relied on statistical regression models that failed to capture the complex nonlinear relationships between carbon emissions and characteristic *** this study,we propose a machine learning algorithm for carbon emissions,a Bayesian optimized XGboost regression model,using multi-year energy carbon emission data and nighttime lights(NTL)remote sensing data from Shaanxi Province,*** results demonstrate that the XGboost algorithm outperforms linear regression and four other machine learning models,with an R^(2)of 0.906 and RMSE of *** observe an annual increase in carbon emissions,with high-emission counties primarily concentrated in northern and central Shaanxi Province,displaying a shift from discrete,sporadic points to contiguous,extended spatial *** autocorrelation clustering reveals predominantly high-high and low-low clustering patterns,with economically developed counties showing high-emission clustering and economically relatively backward counties displaying low-emission *** findings show that the use of NTL data and the XGboost algorithm can estimate and predict carbon emissionsmore accurately and provide a complementary reference for satellite remote sensing image data to serve carbon emission monitoring and *** research provides an important theoretical basis for formulating practical carbon emission reduction policies and contributes to the development of techniques for accurate carbon emission estimation using remote sensing data.

关键词： Machine learning Energy carbon emissions Nighttime light Spatial distribution

Self-assembly of two pairs of homochiral M2L4 coordination capsules with varied confined space using Tr?ger's base ligands

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Chinese Chemical Letters 2025年第2期36卷 360-365页

作者： yi Zhou Wei Zhang Rong Fu jiaxin Dong yuxuan Liu Zihang Song han han Kang Cai College of Chemistry Nankai University Department of Chemistry Northwestern University Department of Chemistry The University of Hong Kong

Chiral coordination molecular cages/capsules with discrete nanoconfined chiral cavities demonstrate significant potential applications across various fields. In this study, we utilized Tr?ger's base as the building block to design and synthesize two pairs of enantiopure ligands. These ligands were then self-assembled with Pd(II) ions through chiral self-sorting coordination, resulting in the formation of two pairs of homochiral M2L4-type coordination molecular capsules. Notably, due to differences in the substitution positions on the Tr?ger's base, these two pairs of enantiomeric coordination molecular capsules exhibited distinct levels of cavity closures, cavity sizes, and host-guest recognition properties. This research offers valuable insights into the construction of novel chiral molecular capsules and the regulation of confined cavities.

关键词： Chirality Host-guest recognition Metal-organic capsule Self-sorting Tröger's base

Trifluoromethylative homo-coupling of carbonyl compounds

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Chinese Chemical Letters 2025年第1期36卷 283-287页

作者： Xinlong han Huiying Zeng Chao-jun Li The State Key Laboratory of Applied Organic Chemistry Lanzhou UniversityLanzhou 730000China Department of Chemistry FQRNT Centre for Green Chemistry and CatalysisMcGill UniversityMontrealQuebecH3A 0B8Canada

Carbonyl compounds are abundant in nature and represent a substantial portion of biomass *** significant recent progress in homo-coupling of carbonyl compounds,achieving their deoxyfunctionalization homo-coupling remains a highly intricate ***,we report an entirely novel reaction paradigm:the trifluoromethylative homo-coupling of carbonyl compounds via hydrazones,which enables the formation of three C(sp^(3))-C(sp^(3))bonds in a single *** method provides a new pathway for synthesizing trifluoromethylative coupling product which has unique applications in both fields of medical and material *** investigations have unveiled that the formation of a trifluoromethyl-substituted benzyl radical plays a pivotal role as a key intermediate in this reaction.

关键词： Carbonyl compounds Trifluoromethylation Homo-coupling C(sp^(3))-C(sp^(3))bond formation

Multi-interface structure design of bamboo-based carbon/Co/CoO composite electromagnetic wave absorber based on biomimetic honeycomb-shaped superstructure

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International journal of Minerals,Metallurgy and Materials 2025年第3期32卷 631-644页

作者： yanting Wang He han Huiyang Bian yanjun Li Zhichao Lou jiangsu Co-Innovation Center of Efficient Processing and Utilization of Forest Resources College of Materials Science and EngineeringNanjing Forestry UniversityNanjing 210037China College of Light Industry and Food Engineering Nanjing Forestry UniversityNanjing 210037China

The rapid development of 5G communication technology and smart electronic and electrical equipment will inevitably lead to electromagnetic radiation *** heterointerface polarization relaxation through nanostructure design and interface modifica-tion has proven to be an effective strategy to obtain efficient electromagnetic wave ***,this work implements an innovative method that combines biomimetic honeycomb superstructure to constrain hierarchical porous heterostructure composed of Co/CoO nano-particles to improve the interfacial polarization *** method effectively controlled the absorption efficiency of Co^(2+)through de-lignification modification of bamboo,and combined with the bionic carbon-based natural hierarchical porous structure to achieve uniform dispersion of nanoparticles,which is conducive to the in-depth construction of heterogeneous *** addition,the multiphase struc-ture brought about by high-temperature pyrolysis provides the best dielectric loss and impedance matching for the ***,the obtained bamboo-based Co/CoO multiphase composite showed excellent electromagnetic wave absorption performance,achieving excel-lent reflection loss(RL)of-79 dB and effective absorption band width of 4.12 GHz(6.84-10.96 GHz)at low load of 15wt%.Among them,the material’s optimal radar cross-section(RCS)reduction value can reach 31.9 dB·m^(2).This work provides a new approach to the micro-control and comprehensive optimization of macro-design of microwave absorbers,and offers new ideas for the high-value utiliza-tion of biomass materials.

关键词： biomass honeycomb porous heterojunction structure interfacial polarization electromagnetic wave absorption

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Frog tongue-inspired wettable microfibers for particles capture

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Science Bulletin 2025年第3期70卷 383-389页

作者： jiahui Guo Lingyu Sun han Zhang yuanjin Zhao Department of Rheumatology and Immunology Nanjing Drum Tower HospitalSchool of Biological Science and Medical EngineeringSoutheast UniversityNanjing 210096China Shenzhen Research Institute Southeast UniversityShenzhen 518071China Chemistry and Biomedicine Innovation Center ChemBioMed Interdisciplinary Research CenterNanjing UniversityNanjing 210023China

Fibers have been of great significance in our daily lives,especially in the industrial production of *** in this area has been focused on developing microfibers with superior functions to enhance the filtration performances of the ***,inspired by the frog’s predation mechanism using its tongues to swiftly grab flying insects,we propose novel porous wettable microfibers from microfluidics to efficiently capture particles in the air for *** pre-dispersing LP emulsions into polyurethane(PU),porous microfibers dispersed with oil droplets could be continuously spun from a co-flow microfluidic device based on the quick phase inversion of *** design an optimal system with frog-tongue-like interfacial adhesion properties,the wettability performances of the porous microfibers are investigated under full,partial,and no oil coverage *** implemented in a mask,the 3D patterned networks based on the frog-tongue-inspired microfibers have been proven with remarkable particle capture performances while maintaining good air *** on these features,we believe that frog-tongue-inspired microfibers and their derived masks are of practical significance in multiple applications.

关键词： Bioinspired Microfluidics Microfiber Wettability Mask

Exploring catalyst developments in heterogeneous CO2 hydrogenation to methanol and ethanol:A journey through reaction pathways

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journal of Energy Chemistry 2025年第2期101卷 345-384页

作者： Rasoul Salami yimin Zeng Xue han Sohrab Rohani ying Zheng Department of Chemical and Biochemical Engineering Western University Canmet MATERIALS Natural Resources Canada

The pursuit of alternative fuel generation technologies has gained momentum due to the diminishing reserves of fossil fuels and global warming from increased *** the proposed methods,the hydrogenation of CO2to produce marketable carbon-based products like methanol and ethanol is a practical approach that offers great potential to reduce *** significant volumes of methanol are currently produced from CO2,developing highly efficient and stable catalysts is crucial for further enhancing conversion and selectivity,thereby reducing process *** in-depth examination of the differences and similarities in the reaction pathways for methanol and ethanol production highlights the key factors that drive C-C *** these factors guides us toward developing more effective catalysts for ethanol *** this paper,we explore how different catalysts,through the production of various intermediates,can initiate the synthesis of methanol or *** catalytic mechanisms proposed by spectroscopic techniques and theoretical calculations,including operando X-ray methods,FTIR analysis,and DFT calculations,are summarized and *** following discussion explores the structural properties and composition of catalysts that influence C-C coupling and optimize the conversion rate of CO2into ***,the review examines recent catalysts employed for selective methanol and ethanol production,focusing on single-atom catalysts.

关键词： CO 2 hydrogenation Methanol Ethanol Catalytic mechanism Operando techniques Single atom catalyst Tandem catalyst