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A new scheme of climate-vegetation regionalization in the Hengduan Mountains Region

Science China Earth Sciences 2024年第3期67卷 751-768页

作者： xueqin zhang Xiaoming XU Xiang LI Peng CUI Du ZHENG Key Laboratory of Land Surface Pattern and Simulation Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China China-Pakistan Joint Research Center on Earth Sciences Chinese Academy of Sciences-Higher Education Commission of PakistanIslamabad 45320Pakistan

The Hengduan Mountains Region(HMR) is essential for the future ecological protection, clean energy production,Sichuan-Xizang and Yunnan-Xizang railways, and other major infrastructure projects in China. The distributions of climate and vegetation exhibit significant regional differentiation and vertical zonality due to the rugged longitudinal ranges and gorges and the complex disaster-prone environments in HMR. Therefore, it is urgent to develop the climate-vegetation regionalization in HMR to effectively satisfy the national requirements such as agricultural production and ecological protection, mountain disaster risk prevention, and major project construction. We here develop a new scheme of climate-vegetation regionalization with the latest demarcation outcome of HMR, the ground observation from 122 meteorological stations in HMR and its surrounding areas during 1990–2019, and the high-precision remote sensing data of land cover types. The new scheme first constructs the regionalization index system, fully considering the extraordinarily complicated geomorphic pattern of mountains and valleys, the scarcity of meteorological observations, and the remarkable differentiation of climate and vegetation in HMR. The system consists of three primary regionalization indices(i.e., days with daily average temperature steady above 10°C, aridity index, and main vegetation types, dividing the temperature zones, moisture regions, and vegetation subregions, respectively) and three auxiliary indices of the accumulated temperature above 10°C, and the temperatures in January and July. Then, the HMR is divided into five temperature zones, 20 moisture regions, and 55 vegetation subregions. Compared with previous regionalization schemes, the new scheme optimizes the climate spatial interpolation model of thin plate smoothing spline suitable for the unique terrain in HMR. Moreover, the disputed division index threshold between different climatic zones(regions) is scientifically clarified using geographical detectors. Specifically, t

关键词： Climate-vegetation regionalization Thin plate smoothing spline(TPSS) GeoDetector Stepwise downscaling pane division method Hengduan Mountains Region

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Calcium-based polymers for suppression of soil acidification by improving acid-buffering capacity and inhibiting nitrification

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Journal of Environmental Sciences 2024年第5期139卷 138-149页

作者： Fei Kang Yunshan Meng Yanning Ge Yun zhang Haixiang Gao xueqin Ren Jie Wang Shuwen Hu Beijing Key Laboratory of Farmland Soil Pollution Prevention-control and Remediation College of Resources and Environmental SciencesChina Agricultural UniversityBeijing 100193China Department of Applied Chemistry China Agricultural UniversityBeijing 100193China

Soil acidification is a major threat to agricultural sustainability in tropical and subtropical regions.Biodegradable and environmentally friendly materials,such as calcium lignosulfonate(CaLS),calcium poly(aspartic acid)(PASP-Ca),and calcium polyγ-glutamic acid(γ-PGA-Ca),are known to effectively ameliorate soil acidity.However,their effectiveness in inhibiting soil acidification has not been studied.This study aimed to evaluate the effect of CaLS,PASP-Ca,andγ-PGA-Ca on the resistance of soil toward acidification as directly and indirectly(i.e.,via nitrification)caused by the application of HNO_(3)and urea,respectively.For comparison,Ca(OH)_(2)and lignin were used as the inorganic and organic controls,respectively.Among the materials,γ-PGA-Ca drove the substantial improvements in the pH buffering capacity(pHBC)of the soil and exhibited the greatest potential in inhibiting HNO_(3)-induced soil acidification via protonation of carboxyl,complexing with Al~(3+),and cation exchange processes.Under acidification induced by urea,CaLS was the optimal one in inhibiting acidification and increasing exchangeable acidity during incubation.Furthermore,the sharp reduction in the population sizes of ammonia-oxidizing bacteria(AOB)and ammonia-oxidizing archaea(AOA)confirmed the inhibition of nitrification via CaLS application.Therefore,compared to improving soil pHBC,CaLS may play a more important role in suppressing indirect acidification.Overall,γ-PGA-Ca was superior to PASP-Ca and CaLS in enhancing the soil pHBC and the its resistance to acidification induced by HNO_(3) addition,whereas CaLS was the best at suppressing urea-driven soil acidification by inhibiting nitrification.In conclusion,these results provide a reference for inhibiting soil re-acidification in intensive agricultural systems.

关键词： Calcium-based polymer Soil acidification pH buffering capacity Nitrification inhibition

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Strong synergy between physical and chemical properties:Insight into optimization of atomically dispersed oxygen reduction catalysts

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Journal of Energy Chemistry 2024年第4期91卷 36-49页

作者： Yifan zhang Linsheng Liu Yuxuan Li xueqin Mu Shichun Mu Suli Liu Zhihui Dai School of Chemistry and Molecular Engineering Nanjing Tech UniversityNanjing 211816JiangsuChina State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of Technology InstitutionWuhan 430070HubeiChina School of Chemistry and Materials Science Nanjing Normal UniversityNanjing 210023JiangsuChina

Atomically dispersed catalysts exhibit significant influence on facilitating the sluggish oxygen reduction reaction(ORR)kinetics with high atom economy,owing to remarkable attributes including nearly 100%atomic utilization and exceptional catalytic functionality.Furthermore,accurately controlling atomic physical properties including spin,charge,orbital,and lattice degrees of atomically dispersed catalysts can realize the optimized chemical properties including maximum atom utilization efficiency,homogenous active centers,and satisfactory catalytic performance,but remains elusive.Here,through physical and chemical insight,we review and systematically summarize the strategies to optimize atomically dispersed ORR catalysts including adjusting the atomic coordination environment,adjacent electronic orbital and site density,and the choice of dual-atom sites.Then the emphasis is on the fundamental understanding of the correlation between the physical property and the catalytic behavior for atomically dispersed catalysts.Finally,an overview of the existing challenges and prospects to illustrate the current obstacles and potential opportunities for the advancement of atomically dispersed catalysts in the realm of electrocatalytic reactions is offered.

关键词： Atomically dispersed catalysts Coordination environment Electronic orbitals Inter-site distance effect Oxygen reduction reaction

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In situ formation of multiple catalysts for enhancing the hydrogen storage of MgH_(2) by adding porous Ni_(3)ZnC_(0.7)/Ni loaded carbon nanotubes microspheres

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Journal of Magnesium and Alloys 2024年第3期12卷 1227-1238页

作者： Bing zhang Xiubo Xie Yukun Wang Chuanxin Hou xueqin Sun Yuping zhang Xiaoyang Yang Ronghai Yu Wei Du School of Environmental and Material Engineering Yantai UniversityNo.30 Qingquan RoadYantai 264005China Key Laboratory of Aerospace Materials and Performance(Ministry of Education)School of Materials Science and Engineering Beihang UniversityNo.37 Xueyuan RoadBeijing 100191China

MgH_(2) is considered one of the most promising hydrogen storage materials because of its safety,high efficiency,high hydrogen storage quantity and low cost characteristics.But some shortcomings are still existed:high operating temperature and poor hydrogen absorption dynamics,which limit its application.Porous Ni_(3)ZnC_(0.7)/Ni loaded carbon nanotubes microspheres(NZC/Ni@CNT)is prepared by facile filtration and calcination method.Then the different amount of NZC/Ni@CNT(2.5,5.0 and 7.5 wt%)is added to the MgH_(2) by ball milling.Among the three samples with different amount of NZC/Ni@CNT(2.5,5.0 and 7.5 wt%),the MgH_(2)-5 wt%NZC/Ni@CNT composite exhibits the best hydrogen storage performances.After testing,the MgH_(2)-5 wt%NZC/Ni@CNT begins to release hydrogen at around 110℃ and hydrogen absorption capacity reaches 2.34 wt%H_(2) at 80℃ within 60 min.Moreover,the composite can release about 5.36 wt%H_(2) at 300℃.In addition,hydrogen absorption and desorption activation energies of the MgH_(2)-5 wt%NZC/Ni@CNT composite are reduced to 37.28 and 84.22 KJ/mol H_(2),respectively.The in situ generated Mg_(2)NiH_(4)/Mg_(2)Ni can serve as a"hydrogen pump"that plays the main role in providing more activation sites and hydrogen diffusion channels which promotes H_(2) dissociation during hydrogen absorption process.In addition,the evenly dispersed Zn and MgZn2 in Mg and MgH_(2) could provide sites for Mg/MgH_(2) nucleation and hydrogen diffusion channel.This attempt clearly proved that the bimetallic carbide Ni_(3)ZnC_(0.7) is a effective additive for the hydrogen storage performances modification of MgH_(2),and the facile synthesis of the Ni_(3)ZnC_(0.7)/Ni@CNT can provide directions of better designing high performance carbide catalysts for improving MgH_(2).

关键词： Mg-based hydrogen storage material Ni_(3)ZnC_(0.7)/Ni@CNT particles Ni loaded carbon nanotubes Multiple catalysts.

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Mechanical properties of additively-manufactured cellular ceramic structures:A comprehensive study

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Journal of Advanced Ceramics 2022年第12期11卷 1918-1931页

作者： xueqin zhang Keqiang zhang Bin zhang Ying LI Rujie HE Institute of Advanced Structure Technology Beijing Institute of TechnologyBeijing 100081China School of Naval Architecture Ocean and Energy Power EngineeringWuhan University of TechnologyWuhan 430070China

Cellular ceramic structures(CCSs)are promising candidates for structural components in aerospace and modern industry because of their extraordinary physical and chemical properties.Herein,the CCSs with different structural parameters,i.e.,relative density,layer,size of unit cells,and structural configuration,were designed and prepared by digital light processing(DLP)-based additive manufacturing(AM)technology to investigate their responses under compressive loading systematically.It was demonstrated that as the relative density increased and the size of the unit cells decreased,the mechanical properties of one-layer CCSs increased.The mechanical properties of three-layer CCSs were more outstanding than those of the CCSs with one and two layers.In addition,structural configurations also played a vital role in the mechanical properties of the CCSs.Overall,the mechanical properties of the CCSs from superior to inferior were that with the structural configurations of modified body-centered cubic(MBCC),Octet,SchwarzP,IWP,and body-centered cubic(BCC).Furthermore,structural parameters also had significant impacts on the failure mode of the CCSs under compressive loading.As the relative density increased,the failure mode of the one-layer CCSs changed from parallel-vertical-inclined mode to parallel-vertical mode.It was worth noting that the size of the unit cells did not alter the failure mode.Inclined fracture took a greater proportion in the failure mode of the multi-layer CCSs.But it could be suppressed by the increased relative density.Similarly,the proportions of the parallel-vertical mode and the fracture along a specific plane always changed with the variation of the structural configurations.This study will serve as the base for investigating the mechanical properties of the CCSs.

关键词： cellular ceramic structures(CCSs) mechanical properties failure mode structural parameters

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Quantitative characterization of defects in stereolithographic additive manufactured ceramic using X-ray computed tomography

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Journal of Materials Science & Technology 2022年第23期118卷 153-166页

作者： Keqiang zhang Qiaoyu Meng xueqin zhang Zhaoliang Qu Rujie He Institute of Advanced Structure Technology Beijing Institute of TechnologyBeijing 100081China Beijing Key Laboratory of Lightweight Multi-Functional Composite Materials and Structures Beijing Institute of TechnologyBeijing 100081Chin

Ceramics have been widely fabricated by additive manufacturing(AM).Compared to conventional technologies,the strength of additive manufactured ceramic is relatively low owing to the formation of defects during manufacturing process.These defects have significant effects on the microstructure and mechanical properties of additive manufactured ceramics.However,systematic research on defects,including defect geometrical features,quantitative statistics,and formation mechanism,as well as the intrinsic relationship with mechanical properties,need to be studied in depth.In this work,Al2 O3 ceramics were prepared from photosensitive slurries with different solid loadings by using stereolithographic(SL)additive manufacturing.The defects,including their sizes and distributions,in both green and sintered bodies were investigated by using scanning electron microscopy(SEM)and X-ray computed tomography(X-CT).Geometrical features and quantitative statistics of the defects were evaluated and discussed to reveal their formation mechanism.Moreover,the intrinsic relationship between defects and mechanical properties of the additive manufactured ceramic was revealed.This study can give some fundamental understanding of the defects in additive manufactured ceramics.

关键词： Ceramic Stereolithographic additive manufacturing Defects X-CT Strength

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The triggering mechanisms for different types of snow avalanches in the continental snow climate of the central Tianshan Mountains

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Science China Earth Sciences 2022年第12期65卷 2308-2321页

作者： Jiansheng HAO Peng CUI xueqin zhang Lanhai LI Key Laboratory of Land Surface Pattern and Simulation Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China China-Pakistan Joint Research Center on Earth Sciences Chinese Academy of Sciences-Higher Education Commission of PakistanIslamabad 45320Pakistan State Key Laboratory of Desert and Oasis Ecology Xinjiang Institute of Ecology and GeographyChinese Academy of SciencesUrumqi 830011China Ili Station for Watershed Ecosystem Research Chinese Academy of SciencesXinyuan 835800China

Climate change and human activities have increased avalanche risks in alpine mountains.Therefore,strengthening the research on mitigating and controlling avalanche disasters is indispensable for sustainable socio-economic development in mountainous areas.Early avalanche warning is an essential means of avalanche disaster prevention.However,the theoretical development and application of avalanche warning strategies remain limited due to the lack of systematic understanding of the triggering mechanisms of avalanches.Based on observational data(2015–2019)of avalanches,snowpack,meteorological parameters,surface soil temperature and moisture,and topography in avalanche-prone areas in the central Tianshan Mountains,we analyzed the characteristics of different types of avalanches under a continental snow climate and the environmental factors(such as meteorological conditions and snowpack)that trigger avalanches,as well as the triggering mechanisms for different types of avalanches under the continental snow climate in terms of snow-layer shear fracture modes.We found that the snowpack parameters,weather conditions,and soil temperature and moisture varied significantly among the stages of snow accumulation,stabilization,and melting,resulting in different avalanches prevailing in different stages of snowpack evolution.Moreover,the snow-layer fractures were driven by single external factors or the combined multiple factors under the continental snow climate.Fifty-four percent of the avalanche events in the study area occurred during or after a snowfall,with 36%related to sudden increases in temperature.Then considering different triggering scenarios,snowpack evolution stages,and the coupling of intrinsic and extrinsic drivers of triggering snow-layer shear failure,we constructed five snow-layer shear fracture modes and twelve avalanche-triggering modes on mountain slopes under a continental snow climate.

关键词： Continental snow climate Avalanche disaster Snow-layer failure Shear fracture modes Avalanche-triggering modes Central Tianshan Mountains

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Zokor activity promotes soil water infiltration in the Mu Us sandy land of northern Shaanxi,China

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Pedosphere 2024年第1期34卷 136-145页

作者： Miao GAN Xuchao ZHU xueqin YANG Xiaorong WEI Qingyin zhang Tongchuan LI Ming'an SHAO Meixia MI Xi YANG Mingyu CHEN State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau Northwest A&F UniversityYangling 712100China College of Natural Resources and Environment Northwest A&F UniversityYangling 712100China State Key Laboratory of Soil and Sustainable Agriculture Institute of Soil ScienceChinese Academy of SciencesNanjing 210008China Henan Institute of Science and Technology Xinxiang 453003China College of Urban and Rural Construction Shanxi Agricultural UniversityJinzhong 030801China

Zokors are common subterranean rodents that inhabit agricultural fields, shrublands, and grasslands in the arid and semi-arid regions of China. Zokor burrowing activities can alter soil structure and affect soil hydrological processes;however, there are few studies regarding their effects on soil preferential flow in the Mu Us sandy land. An evaluation of the effects of zokor disturbance on their habitat and soil water is important for understanding the ecological role of zokors in the soil ecosystem of the Mu Us sandy land. A field dye-tracing experiment was conducted in the Gechougou watershed on the southeastern edge of the Mu Us sandy land to investigate the effect of zokor burrowing activity on soil preferential flow characteristics. Our results showed that the density of zokor tunnels was the highest(0.40–0.46 m m^(-2)) under 30%–50% vegetation coverage and that the tunnels were approximately 3 cm from the surface.Both stained area ratio and stained path number were higher at sites with zokors than without zokors. Stained path widths were 10–80 and > 80 mm at zokor-harboring sites exhibiting homogeneous flow and heterogeneous finger flow, respectively. In the absence of zokors, homogeneous flow and highly interacted macropore flow were predominant. Soil water content below the zokor tunnels was higher than that above the tunnels. Moderate disturbance of soil structure by zokor activity facilitated soil water infiltration. These results enabled a better understanding of the effect of soil fauna on soil structure and hydrological processes and provided recommendations for ecological construction and renovation in arid and semi-arid regions.

关键词： eld dye-tracing experiment preferential flow soil fauna stained area ratio stained path number stained path width subterranean rodent surface tortoise crack

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miR-30a-5p/PHTF2 axis regulates the tumorigenesis and metastasis of lung adenocarcinoma

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BIOCELL 2024年第4期48卷 581-590页

作者： LIJUAN zhang QINGYIN MENG LI ZHUANG QUAN GONG XIANDA HUANG xueqin LI SHIJUAN LI GUOQIN WANG XICAI WANG Department of Rehabilitation and Palliative Medicine The Third Affiliated Hospital of Kunming Medical UniversityYunnan Cancer HospitalKunmingChina Department of Pathology The Third Affiliated Hospital of Kunming Medical UniversityYunnan Cancer HospitalKunmingChina Emergency Department(Outpatient Chemotherapy Center) The Third Affiliated Hospital of Kunming Medical UniversityYunnan Cancer HospitalKunmingChina Department of Cancer BioTreatment Center The Third Affiliated Hospital of Kunming Medical UniversityYunnan Cancer HospitalKunmingChina Department of Cancer Institute The Third Affiliated Hospital of Kunming Medical UniversityYunnan Cancer HospitalKunmingChina

Background:Lung adenocarcinoma is a very pervasive histological form of lung cancers,and inhibiting metastasis is crucial for effective treatment.In this investigation,we explored the functional interaction of miR-30a-5p and the putative transcription factor 2 of the homeodomain(PHTF2)in dictating the aggressiveness and metastasis of lung adenocarcinoma.Method:We collected clinical samples to evaluate the expression patterns of miR-30a-5p and PHTF2 in lung adenocarcinoma along with normal tissues.Cellular experiments including cell count kit(CCK)-8 growth assay,apoptosis analysis,migration and invasion examinations were performed to assess the aggressiveness of lung adenocarcinoma cells.Furthermore,we examined tumorigenesis and metastasis in a nude mouse model.Results:MiR-30a-5p exhibited downregulation pattern in lung adenocarcinoma samples.Transfection of miR-30a-5p mimic in lung adenocarcinoma cells resulted in the suppression of malignant characteristics.Notably,the administration of miR-30a-5p mimic also curbed tumorigenesis and metastasis of lung adenocarcinoma cells in animal model.Moreover,PHTF2 was found to be a molecular target of miR-30a-5p.Upregulating PHTF2 counteracted the tumor-suppressive effect of the miR-30a-5p mimic.Conclusion:miR-30a-5p functions as a tumor-suppressive molecule while PHTF2 acts as an oncogenic factor in the development and metastasis of lung adenocarcinoma.Therefore,targeting miR-30a-5p and PHTF2 could be developed into a promising therapeutic approach for inhibiting metastasis in lung adenocarcinoma.

关键词： Lung cancer Malignant phenotype Tumor formation Tumor suppressor Oncogene

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Impacts of Climate Change on Snow Avalanche Activity Along a Transportation Corridor in the Tianshan Mountains

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International Journal of Disaster Risk Science 2023年第4期14卷 510-522页

作者： Jiansheng Hao xueqin zhang Peng Cui Lanhai Li Yan Wang Guotao zhang Chaoyue Li Key Laboratory of Land Surface Pattern and Simulation Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China China-Pakistan Joint Research Center on Earth Sciences Chinese Academy of Sciences-Higher Education Commission of PakistanIslamabad 45320Pakistan State Key Laboratory of Desert and Oasis Ecology Xinjiang Institute of Ecology and GeographyChinese Academy of SciencesUrumqi 830011China Ili Station for Watershed Ecosystem Research Chinese Academy of SciencesXinyuan 835800China

Snow avalanches can repeatedly occur along the same track under diferent snowpack and meteorological conditions during the snow season in areas of snow avalanche activity.The snowfall,air temperature,and snow cover can change dramatically in a warming climate,causing signifcant changes in the snow avalanche risk.But how the risk of snow avalanche activity during the snow season will change under a warming climate remains an open question.Based on the observed meteorological and snowpack data from 1968 to 2021 and the snow avalanche activity data during the 2011–2021 snow seasons along a transportation corridor in the central Tianshan Mountains that has a typical continental snow climate,we analyzed the temporal distribution of the snow avalanche activity and the impacts of climate change on it.The results indicate that the frequency of the snow avalanche activity is characterized by a Gaussian bimodal distribution,resulting from interactions between the snowfall,air temperature,and snowpack evolution.In addition,the active period of wet snow avalanches triggered by temperature surges and high solar radiation has gradually moved forward from the second half to the frst half of March with climate warming.The frequency and size of snowfall-triggered snow avalanches showed only a slight and insignifcant increase.These fndings are important for rationally arranging snow avalanche relief resources to improve the risk management of snow avalanche disasters,and highlight the necessity to immediately design risk mitigation strategies and disaster risk policies to improve our adaptation to climate change.

关键词： Climate change Continental snow climate Risk management Snow avalanches Tianshan mountains

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