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Journal of Electronic Science and Technology 2024年第3期22卷 69-79页

作者： Yin Zhang ding-Feng Duan School of Resources and Environment University of Electronic Science and Technology of ChinaChengdu611731China

We estimate tree heights using polarimetric interferometric synthetic aperture radar(PolInSAR)data constructed by the dual-polarization(dual-pol)SAR data and random volume over the ground(RVoG)*** the Sentinel-1 SAR dual-pol(SVV,vertically transmitted and vertically received and SVH,vertically transmitted and horizontally received)configuration,one notes that S_(HH),the horizontally transmitted and horizontally received scattering element,is *** S_(HH)data were constructed using the SVH data,and polarimetric SAR(PolSAR)data were *** proposed approach was first verified in simulation with satisfactory *** was next applied to construct PolInSAR data by a pair of dual-pol Sentinel-1A data at Duke Forest,North Carolina,*** to local observations and forest descriptions,the range of estimated tree heights was overall *** the heights with the ICESat-2 tree heights at 23.sampling locations,relative errors of 5 points were within±3.%.Errors of 8 points ranged from 3.%to 40%,but errors of the remaining 10 points were>40%.The results should be encouraged as error reduction is *** instance,the construction of PolSAR data should not be limited to using SVH,and a combination of SVH and SVV should be ***,an ensemble of tree heights derived from multiple PolInSAR data can be considered since tree heights do not vary much with time frame in months or one season.

关键词： Constructed polarimetric SAR data Dual polarization Sentinel-1 SAR data Polarimetric interferometric SAR Random volume over the ground model Tree height estimation

Summer extreme precipitation patterns and synoptic-scale circulation precursors over the Tibetan Plateau

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Science China Earth Sciences 2024年第5期67卷 1625-1638页

作者： Zhiyuan ding Yao HA Zhong ZHONG College of Meteorology and Oceanography National University of Defense TechnologyChangsha 410073China Key Laboratory for Virtual Geographic Environment School of Geography ScienceNanjing Normal UniversityNanjing 210023China Jiangsu Collaborative Innovation Center for Climate Change School of Atmospheric SciencesNanjing UniversityNanjing 210023China

In the context of global warming,the extreme summer precipitation over the Tibetan Plateau(TP)has changed *** this study,the summer(June–August)extreme precipitation on the TP was classified into three spatial types by applying the K-means clustering method to the Third Pole Region long time-series high-resolution(1/3.°)precipitation dataset(TPHi Pr,1979–2020).The characteristics of the circulation anomalies and precursors corresponding to the extreme precipitation on the TP in summer during 1979–2020 were *** results showed that the summer extreme precipitation of the TP can be categorized into northwestern(NW),southeastern(SE),and southern Himalayan(HS)types based on extreme precipitation *** NW and SE types are mainly influenced by anomalous signals in the mid-to-high latitude regions upstream of them,whereas the HS type is controlled by the localized subtropical anomalous *** the 8th day before the onset of the NW type,an anomalous cyclone was observed in the western Atlantic Ocean(60°W,50°N),which triggered the west-to-east quasi-latitudinal propagation of Rossby *** the onset day of the NW type,the upper troposphere showed positive-negative-positive geopotential height anomalies along the latitudinal 40°N from the Caspian Sea,the western part of Xinjiang,to the northeastern *** entered from the Arabian Sea along the southeastern edge of the anomalous cyclone on the southwestern TP and converged in the northwestern *** to the NW type,the precursors of the SE type appeared at higher latitudes and were more *** the 8th day before the onset of the SE type,an anomalous cyclone occurred near Greenland(60°W,70°N)and excited Rossby waves propagating *** the onset day of the SE type,the upper troposphere showed negative-positive-negative geopotential height anomalies across Eurasia from the Ural Mountains and the Iranian Plateau to the northern TP in the northwest-southeast directi

关键词： Tibetan Plateau Summer extreme precipitation Atmospheric circulation anomaly Precursor Teleconnection wave train

Large magnetostriction of Nd_(0.2)Tb_(0.3.Dy_(0.5)Fe_(1.93./epoxy composites in a wide temperature range

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Journal of Rare Earths 2024年第4期42卷 705-709页

作者： Hehe ding Yangguang Shi Shaolong Tang MIIT Key Laboratory of Aerospace Information Materials and Physics Department of Applied PhysicsNanjing University of Aeronautics and AstronauticsNanjing210016China National Laboratory of Solid State Microstructures Nanjing UniversityNanjing210093China

We report the magnetostrictive performance of the Nd_(0.2)Tb_(0.3.Dy_(0.5)Fe_(1.93./epoxy *** of M?ssbauer spectra and the XRD results indicate that the easy magnetic direction of the Nd_(0.2)Tb_(0.3.Dy_(0.5)Fe_(1.93.compound is alongdirection with spontaneous magnetostrictionλ111 of1900 ***-oriented Nd_(0.2)Tb_(0.3.Dy_(0.5)Fe_(1.93./epoxy composites with particle volume fractions of20 vol%-55 vol%were *** measurements demonstrate that the composite is highly *** raw material cost of Nd_(0.2)Tb_(0.3.Dy_(0.5)Fe_(1.93.is about 85%of that of the Terfenol-D(Tb_(0.3.Dy_(0.7)Fe_(2))***_(0.2)Tb_(0.3.Dy_(0.5)Fe_(1.93./epoxy composites possess comparable magnetostriction with those composites made of Tb_(0.3.Dy_(0.7)Fe_(2)*** room temperature,the magnetostrictionλ_Ⅱof the Nd_(0.2)Tb_(0.3.Dy_(0.5)Fe_(1.93./epoxy composite reaches 420 ppm at a low field of 80 kA/m and about1000 ppm at 23. kA/*** addition,the composite exhibits a large saturation magnetostrictionλ_Ⅱover1200 ppm from 3.0 to 100 K,suggesting its potential applications as a low-cost magnetostrictive material in a wide temperature ***,the current study offers an opportunity to widen the operating temperature range of the magnetostrictive composite.

关键词： Magnetostrictive composite Nd_(0.2)Tb_(0.3.Dy_(0.5)Fe_(1.93. Wide temperaturerange Laves phase Rare earths

A human-sensitive frequency band vibration isolator for heavy-duty truck seats

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Applied Mathematics and Mechanics(English Edition) 2024年第10期45卷 1733-1748页

作者： Qingqing LIU Shenlong WANG Ge YAN Hu ding Haihua WANG Qiang SHI Xiaohong ding Huijie YU School of Mechanical Engineering University of Shanghai for Science and TechnologyShanghai 200093China State Key Laboratory of Mechanical System and Vibration School of Mechanical EngineeringShanghai Jiao Tong UniversityShanghai 200240China Shanghai Key Laboratory of Mechanics in Energy Engineering Shanghai Frontier Science Center of MechnoinformaticsShanghai Institute of Applied Mathematics and MechanicsSchool of Mechanics and Engineering ScienceShanghai UniversityShanghai 200072China State Key Laboratory of Advanced Design and Manufacturing for Vehicle Body College of Mechanical and Vehicle EngineeringHunan UniversityChangsha 410082China Yanfeng Adient Seating Co. Ltd.Shanghai 201315China College of Mechanical and Electrical Engineering Jiaxing Nanhu UniversityJiaxing 314001Zhejiang ProvinceChina

In this study,a human-sensitive frequency band vibration isolator(HFBVI)with quasi-zero stiffness(QZS)characteristics for heavy-duty truck seats is designed to improve the comfort of heavy-duty truck drivers on uneven ***,the analytical expressions for the force and displacement of the HFBVI are derived with the Lagrange equation and d'Alembert's principle,and are validated through the prototype restoring force ***,the harmonic balance method(HBM)is used to obtain the dynamic responses under harmonic excitation,and further the influence of pre-stretching on the dynamic characteristics and transmissibility is ***,the experimental prototype of the HFBVI is fabricated,and vibration experiments are conducted under harmonic excitation to verify the vibration isolation performance(VIP)of the proposed vibration *** experimental results indicate that the HFBVI can effectively suppress the frequency band(4-8 Hz)to which the human body is sensitive to vertical *** addition,under real random road spectrum excitation,the HFBVI can achieve low-frequency vibration isolation close to 2 Hz,providing new prospects for ensuring the health of heavy-duty truck drivers.

关键词： human-sensitive frequency band quasi-zero stiffness(QZS) heavy-duty truck seat real random road spectrum low-frequency vibration isolation

Does the continuous wetting of the Tibetan Plateau contribute to the accelerated degradation of permafrost?

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Science China Earth Sciences 2024年第5期67卷 1714-1718页

作者： Yuyang WANG Jinzhi ding Shilong PIAO Sino-French Institute for Earth System Science College of Urban and Environmental SciencesPeking UniversityBeijing 100871China State Key Laboratory of Tibetan Plateau Earth System Environment and ResourcesInstitute of Tibetan Plateau ResearchChinese Academy of SciencesBeijing 100101China

Global warming is causing the Tibetan permafrost to degrade, as evidenced by rising ground temperatures, thicker active layer thickness, thinner permafrost layer, and melting underground ice, etc.(Ran et al., 2018;Wang et al., 2020).The degradation of permafrost not only profoundly alters the carbon cycling processes in high-altitude ecosystems,thereby influencing the regional climate system, but also affects landscape hydrological connectivity。

关键词： Tibetan landscape altitude

Analytical model for predicting time-dependent lateral deformation of geosynthetics-reinforced soil walls with modular block facing

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第2期16卷 711-725页

作者： Luqiang ding Chengzhi Xiao Feilong Cui School of Civil and Transportation Engineering Hebei University of TechnologyTianjin300401China

To date,few models are available in the literature to consider the creep behavior of geosynthetics when predicting the lateral deformation(d)of geosynthetics-reinforced soil(GRS)retaining *** this study,a general hyperbolic creep model was first introduced to describe the long-term deformation of geosynthetics,which is a function of elapsed time and two empirical parameters a and *** conventional creep tests with three different tensile loads(Pr)were conducted on two uniaxial geogrids to determine their creep behavior,as well as the a-Pr and b-Pr *** test results show that increasing Pr accelerates the development of creep deformation for both ***,a and b respectively show exponential and negatively linear relationships with Pr,which were confirmed by abundant experimental data available in other *** on the above creep model and relationships,an accurate and reliable analytical model was then proposed for predicting the time-dependent d of GRS walls with modular block facing,which was further validated using a relevant numerical investigation from the previous *** evaluation and comparison of the proposed model with six available prediction models were *** a parametric study was carried out to evaluate the effects of wall height,vertical spacing of geogrids,unit weight and internal friction angle of backfills,and factor of safety against pullout on d at the end of construction and 5 years *** findings show that the creep effect not only promotes d but also raises the elevation of the maximum d along the wall ***,the limitations and application prospects of the proposed model were discussed and analyzed.

关键词： Geosynthetics Creep behavior Geosynthetics-reinforced soil(GRS)walls Lateral deformation Analytical model

Dynamic impact properties of deep sandstone under thermal-hydraulicmechanical coupling loads

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Journal of Mountain Science 2024年第6期21卷 2113-2129页

作者： CAO Chunhui ding Haonan ZOU Baoping School of Civil Engineering and Architecture Zhejiang University of Science and TechnologyHangzhou 310023China Zhejiang-Singapore Joint Laboratory for Urban Renewal and Future City Hangzhou 310023China

The deep rock mass within coal mines situated in a challenging environment are characterized by high ground stress,high geotemperature,high osmotic water pressure,and dynamic disturbances from mechanical *** investigate the impact of this complex mechanical environment on the dynamic characteristics of roof sandstone in self-formed roadways without coal pillars,standard specimens of deep sandstone from the 2611 upper tunnel working face of the Yongmei Company within the Henan Coal Chemical Industry Group in Henan,China were prepared,and an orthogonal test was *** a self-developed geotechnical dynamic impact mechanics test system,triaxial dynamic impact tests under thermal-hydraulicmechanical coupling conditions were conducted on deep *** results indicate that under high confining pressure,deep sandstone exhibits pronounced brittle failure at low temperatures,with peak strength gradually decreasing as temperature and osmotic water pressure ***,under low confining pressure and low temperature,the brittleness of deep sandstone weakens gradually,while ductility ***,sandstone demonstrates higher peak strength at low temperatures under high axial pressure conditions,lower peak strength at high temperatures,and greater strain under low axial pressure and high osmotic water *** in impact air pressure and osmotic water pressure have proportionally greater effects on peak stress and peak *** 50%of the input strain energy is utilized as effective energy driving the sandstone fracture *** analysis identifies the optimal combination of factors affecting the peak stress and peak strain of *** the coupling effect,intergranular and transgranular fractures occur within the *** images illustrate that the damage forms range from minor damage with multiple fissures to extensive fractures and severe *** study elucidates the varied dynamic impact me

关键词： Deep sandstone Thermal-hydraulicmechanical coupling Dynamic impact Stress-strain Failure Modes Polar analysis

A noval iron-capturing nanocomposites against biofilms for disrupting bacterial nutritional balance

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Science China Chemistry 2024年第6期67卷 1760-1761页

作者： Jinying Lin Qihang ding Yao Sun Department of Oral Implantology Jilin Provincial Key Laboratory of Tooth Development and Bone RemodelingSchool of StomatologyJilin UniversityChangchun130021China Department of Chemistry Korea UniversitySeoul02841Korea National Key Laboratory of Green Pesticide International Joint Research Center for Intelligent Biosensor Technology and HealthCollege of ChemistryCentral China Normal UniversityWuhan430079China

Currently,the escalating crisis of bacterial infections and antibiotic resistance poses a significant global public health challenge[1-3..This situation has driven the search for novel antimicrobial ***,a crucial micr... 详细信息

关键词： metabolism resistance balance

Harnessing bacteria for tumor therapy:Current advances and challenges

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Chinese Chemical Letters 2024年第2期35卷 97-106页

作者： Lina Guo Jinsong ding Wenhu Zhou Xiangya School of Pharmaceutical Sciences Central South UniversityChangsha 410013China Changsha Medical University Academician WorkstationChangsha 410219China Key Laboratory of Biological Nanotechnology of National Health Commission Changsha 410008China

After a century of standstill,bacteria-based tumor therapy has resurged recently benefiting from the revolution of tumor immunotherapy,which provides unique solutions to tackle the obstacles of traditional tumor *** and facultative anaerobes with active tropism can selectively colonize at tumor sites and suppress tumor growth via different mechanisms,serving as attractive tools for tumor treatment either as a monotherapy or combining with other therapies for synergistic anti-tumor *** this critical review,we introduce the recent advances of bacteria-based tumor therapy from the following ***,the general properties of bacteria are reviewed emphasizing on their structural components related to tumor immunotherapy,and the main bacteria that have been used in tumor therapy are ***,the benefits of bacteria for tumor therapy are illustrated,such as tumor targetability,deep penetration,and facile genetic engineering for attenuation,enhanced efficacy,as well as ***,anti-tumor mechanisms of bacteria are summarized,which refer to intrinsic tumoricidal activities,immune activation,bacteria metabolism,and their capability to regulate gut microbiota ***,bacteria could act as carriers to deliver various types of therapeutics to achieve combination therapy with improved *** addition,several challenges for anti-tumor applications of bacteria are discussed regarding the delivery,efficacy and safety issues,and potential solutions are also ***,the possible improvements and perspectives are discussed in the end,which provide a guideline for the design of advanced bacteria-based tumor therapeutics in the future.

关键词： Bacteria Tumor targeting Immunotherapy Combination therapy Genetic engineering Surface decoration

Targeted nanostrategies eliminate pre-metastatic niche of cancer

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Nano Research 2024年第6期17卷 5358-5373页

作者： Juan Wang Ning Zhang Xiuping ding Chengrui Fu Xiaodong Li Baosheng Li Jianxun ding Tianmeng Sun Key Laboratory of Organ Regeneration and Transplantation of Ministry of Education Institute of ImmunologyThe First HospitalJilin University1 Xinmin StreetChangchun 130061China Key Laboratory of Polymer Ecomaterials Changchun Institute of Applied ChemistryChinese Academy of Sciences5625 Renmin StreetChangchun 130022China Department of Radiation Oncology Shandong Cancer Hospital and InstituteShandong First Medical University and Shandong Academy of Medical Sciences440 Jiyan RoadJinan 250117China Department of orthopaedics The Second Hospital of Shandong UniversityShandong University247 Beiyuan StreetJinan 250033China State Key Laboratory of Molecular Engineering of Polymers Fudan University220 Handan RoadShanghai 200433China

Establishing a pre-metastatic niche(PMN)in secondary organs is a prerequisite for cancer *** advances in cancer therapy,the efficient inhibition of PMN formation remains a clinical *** advances in understanding the specific characteristics of PMN and advances in nanotechnology have provided hope for manipulating their microenvironments.A series of nanostrategies have been designed to eliminate the PMN,including the removal of pro-metastatic exosomes from the bloodstream for excretion via the intestines,the targeting and scavenging of myeloid-derived suppressor cells,fibroblasts,and critical extracellular matrix components,and the elimination of circulating tumor cells prior to colonization in distant *** review summarizes the underlying mechanisms of PMN formation,highlights the anti-PMN efficacy of currently reported nanostrategies,and underlines the unresolved questions.

关键词： nanoparticle controlled drug delivery pre-metastatic niche elimination metastasis suppression cancer therapy