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A novel structure of ultra-high-loading small moleculesencapsulated ZIF-8 colloid particles

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Nano Research 2024年第4期17卷 2929-2940页

作者： Pengfei Duan Yunhe An Xiaoxiao Wei Yanjie Tian Di Guan Xiangwen Liu Lanqun Mao Institute of analysis and Testing Beijing Academy of Science and Technology(Beijing Center for Physical and Chemical Analysis)Beijing 100089China College of Chemistry Beijing Normal UniversityBeijing 100875China

The safety of nanoparticle-based drug delivery systems(DDSs)for cancer treatment is still a challenge,restricted by the intrinsic cytotoxicity of drug carriers and leakage of loaded ***,we propose a novel nanocarrier’s cytotoxicity avoidance strategy by synthesizing an encapsulation core–shell structure of zeolitic imidazolate framework-8(ZIF-8)-based colloid particles(CPs)with an amorphous ZIF-8 *** encapsulation structure achieves an ultra-high loading rate(LR)of 90%(i.e.,9 mg doxorubicin(DOX)per 1 mg ZIF-8)for DOX and the protection of DOX from ***,to deliver unit-dose drug,this ultra-high LR of 90%significantly reduces the usage of ZIF-8 to 1.2%(2 orders of magnitude)compared to that of DOX@ZIF-8 with a 10%LR,in which cytotoxicity of ZIF-8 could well below the safety limit and then be relatively ***,drug delivery efficacy,scale-up ability,and universality of this encapsulation structure have been further *** findings suggest the great potential of this ZIF-8-based encapsulation core–shell structure in the field of drug delivery.

关键词： metal-organic frameworks zeolitic imidazolate framework-8(ZIF-8) drug delivery nanoparticles nanostructures

Phenology of different types of vegetation and their response to climate change in the Qilian Mountains,China

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Journal of Mountain Science 2024年第2期21卷 511-525页

作者： ZHAO Kaixin LI Xuemei ZHANG Zhengrong LIU Xinyu Faculty of Geomatics Lanzhou Jiaotong UniversityLanzhou 730070China National-Local Joint Engineering Research center of Technologies and Applications for National geographic State Monitoring Lanzhou 730070China Gansu Provincial Engineering Laboratory for National geographic State Monitoring Lanzhou 730070China

The Qilian Mountains(QM)possess a delicate vegetation ecosystem,amplifying the evident response of vegetation phenology to climate *** relationship between changes in vegetation growth and climate remains *** this end,we used MODIS NDVI data to extract the phenological parameters of the vegetation including meadow(MDW),grassland(GSD),and alpine vegetation(ALV))in the QM from 2002 to ***,we employed path analysis to reveal the direct and indirect impacts of seasonal climate change on vegetation ***,we decomposed the vegetation phenology in a time series using the trigonometric seasonality,Box-Cox transformation,ARMA errors,and Trend Seasonal components model(TBATS).The findings showed a distinct pattern in the vegetation phenology of the QM,characterized by a progressive shift towards an earlier start of the growing season(SOS),a delayed end of the growing season(EOS),and an extended length of the growing season(LOS).The growth cycle of MDW,GSD,and ALV in the QM species is clearly *** SOS for MDW and GSD occurred earlier,mainly between late April and August,while the SOS for ALVs occurred between mid-May and mid-August,a one-month delay compared to the other *** EOS in MDW and GSD were concentrated between late August and April and early September and early January,*** phenology exhibits distinct responses to seasonal temperature and precipitation *** advancement and delay of SOS were mainly influenced by the direct effect of spring temperatures and precipitation,which affected 19.59%and 22.17%of the study area,*** advancement and delay of EOS were mainly influenced by the direct effect of fall temperatures and precipitation,which affected 30.18%and 21.17%of the area,*** the contrary,the direct effects of temperature and precipitation in summer and winter on vegetation phenology seem less noticeable and were mainly influenced by indirect *** indirec

关键词： Vegetation phenology Time series decomposition Path analysis Climate change

中国植物性饮食结构调整具有显著的耕地资源效应

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Science Bulletin 2024年第6期69卷 737-740页

作者：朱晓华张燕朱媛媛李裕瑞 Institute of geographic Sciences and Natural Resources Research Chinese Academy of SciencesBeijing 100101China Key Laboratory of geographic Process analysis&Simulation Hubei Province Central China Normal UniversityWuhan 430079China

Food systems are already a major contributor to land degradation,and changes in global diets will exacerbate this situation[1].Population growth and affluent dietary patterns result in changes in land demand and land-use patterns,and up to 40% of global arable land and more than 30% of global food-crop production are used for animal feed[2].Furthermore,food-feed competition can result in an inadequate food supply[3].

关键词：耕地资源 arable food

Architecture of Graphics System with 3D Acceleration Support for Embedded Operating Systems

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Tsinghua Science and Technology 2024年第3期29卷 863-873页

作者： Alexander Giatsintov Kirill Mamrosenko Pavel Bazhenov center of Visualization and Sattelite Information Technologies Scientific Research Institute for System Analysis of the Russian Academy of Sciences(SRISA RAS)Moscow 117218Russia

An increasing number of tasks now require the use of hardware accelerators to reduce the time required for computation and display the computational *** paper presents a new graphics system architecture for operating systems(OSs)with microkernel architecture,including real-time *** proposed system architecture provides capabilities for displaying graphical images on various information display devices and for accelerating graphical operations on *** architecture of the graphics system uses a concept of allocators to manage system and video memory,provides an abstraction of memory operations with a single interface for video memory management,and simplifies memory handling where incorrect operation is the cause of many failures.A comparison between the performance of a real-time OS and Linux OS implementing the graphics system using the example of a glmark2 benchmark is presented,thereby the superiority of the proposed architecture in several scenarios is demonstrated.

关键词： real-time operating system(RTOS) graphics system rendering system architecture operatingsystem visualization system programming

Interaction of yttrium barrier and calcium-rich phase on production and properties of WC precursor powders and alloys

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Journal of Rare Earths 2024年第1期42卷 228-236,I0008页

作者： Wen He Dunqiang Tan Zhiqiang Yi Zhiqiang Liu School of Materials Science and Engineering Nanchang UniversityNanchang330031China Instrumental analysis center of Nanchang Hangkong University Nanchang330063China

In order to reduce or eliminate the adverse effects of calcium impurity,the interaction of Ca and rare earth Y co-doping on the preparation of WC-Co cemented carbides was investigated.X-ray diffraction,scanning electron microscopy and transmission electron microscopy were employed to analyze the phase compositions,particle sizes and morphologies of them,*** results show that the second type of"yttrium barrier effect"is observed and the adverse influence of Ca-rich phase on tungsten powder can be eliminated by *** flexural strength and fracture toughness of YG6-0.01%Ca+0.09%Y alloy are 2199.5 MPa and 11.49 MPa·m^(1/2),showing improvement of 6.5% and 2.7% compared to YG6 alloy,*** evolutions of Ca-rich phase and Y-rich phase at the every alloy preparation stage of WO_(3),W,WC and cemented carbides are ***,the strengthening mechanism of WC-Co cemented carbide with co-addition of Ca and Y is proposed.

关键词： Yttrium barrier effect Ca-rich phase WC-Co cemented Carbide Microstructures Mechanisms Rare earths

Modelling and validation of flash flood inundation in drylands

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Journal of geographical Sciences 2024年第1期34卷 185-200页

作者： GAO Dan YIN Jie WANG Dandan YANG Yuhan LU Yi CHEN Ruishan School of geographic Sciences East China Normal UniversityShanghai 200241China Key Laboratory of geographic Information Science of Ministry of Education East China Normal UniversityShanghai 200241China National Disaster Reduction center of China Ministry of Emergency Management of People's Republic of ChinaBeijing 100124China School of Design Shanghai Jiao Tong UniversityShanghai 200240China

In the context of climate change and human activities,flood disasters in arid mountainous areas have become increasingly frequent,and seriously threatened the safety of people's lives and *** and accurate flash flood inundation modelling is an essential foundational research area,which can aid in the reduction of casualties and the minimization of disaster losses;however,this modelling is also very difficult,and models need to be urgently developed to address flash flood forecasting and *** objective of this study is to construct a numerical modelling method for flash floods in *** on a 2D high-resolution flood numerical model(Flood Map-Hydro Inundation2D),we hindcasted the dynamic process of flash flooding and show the spatio-temporal characteristics of flash flood inundation for the“8·18”flash flood disaster that occurred in Datong county,Qinghai *** results showed that the model output effectively agreed with the observed inundation after the event in terms of both spatial extent and temporal *** flooding mainly occurred between 00:00 and 01:00 on August 18,***,Hejiazhuang and Longwo villages were affected most *** further conducted model sensitivity analysis and found that the model was highly sensitive to both roughness and hydraulic conductivity in drylands,and the effect of hydraulic conductivity was more *** study confirmed the good performance of our model for the simulation of flash flooding in arid areas and provides a potential method for flash flood assessment and management in arid areas.

关键词： flash flood numerical modelling arid areas Datong county Flood Map-Hydro Inundation2D

A General Simulation Method for Complex Deformation of Irregular-Shaped Origami Configurations

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Acta Mechanica Solida Sinica 2024年第1期37卷 90-98页

作者： Zhaochen Dong Yichao Zhu Xu Guo State Key Laboratory of Structural analysis for Industrial Equipment Department of Engineering MechanicsInternational Research Center for Computational MechanicsDalian University of TechnologyDalian 116023China

Most existing treatments for origami-folding simulations have focused on regular-shaped *** article aims to introduce a general strategy for simulating and analyzing the deformation process of irregular shapes by means of computational capabilities *** better simulate origami deformation with folding orders,the concept of plane follow-up is introduced to achieve automated computer simulation of complex folding patterns,thereby avoiding intersection and penetration between *** on the evaluation criteria such as the lowest storage energy with tightening and the fastest pace from tightening to unfolding,the optimal crease distribution patterns for four irregular(‘N’-,‘T’-,‘O’-,and‘P’-shaped)origami configurations are then presented under five *** the dimensions of the origami are fixed,it is discovered that simpler folding patterns lead to faster deformation of the origami *** the folding complexity is fixed,higher strain energy results in more rapid origami expansion.

关键词： Irregular-shaped origami Complex deformation Computer-aided origami design General simulation

A CMIP6-based assessment of regional climate change in the Chinese Tianshan Mountains

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Journal of Arid Land 2024年第2期16卷 195-219页

作者： LIU Xinyu LI Xuemei ZHANG Zhengrong ZHAO Kaixin LI Lanhai Faculty of Geomatics Lanzhou Jiaotong UniversityLanzhou 730070China National-Local Joint Engineering Research center of Technologies and Applications for National geographic State Monitoring Lanzhou 730070China Gansu Provincial Engineering Laboratory for National geographic State Monitoring Lanzhou 730070China State Key Laboratory of Desert and Oasis Ecology Xinjiang Institute of Ecology and GeographyChinese Academy of SciencesUrumqi 830011China Research center for Ecology and Environment of Central Asia Chinese Academy of SciencesUrumqi 830011China

Climate warming profoundly affects hydrological changes,agricultural production,and human *** and semi-arid areas of China are currently displaying a marked trend of warming and *** Chinese Tianshan Mountains(CTM)have a high climate sensitivity,rendering the region particularly vulnerable to the effects of climate *** this study,we used monthly average temperature and monthly precipitation data from the CN05.1 gridded dataset(1961-2014)and 24 global climate models(GCMs)of the Coupled Model Intercomparison Project Phase 6(CMIP6)to assess the applicability of the CMIP6 GCMs in the CTM at the regional *** on this,we conducted a systematic review of the interannual trends,dry-wet transitions(based on the standardized precipitation index(SPI)),and spatial distribution patterns of climate change in the CTM during *** further projected future temperature and precipitation changes over three terms(near-term(2021-2040),mid-term(2041-2060),and long-term(2081-2100))relative to the historical period(1961-2014)under four shared socio-economic pathway(SSP)scenarios(i.e.,SSP1-2.6,SSP2-4.5,SSP3-7.0,and SSP5-8.5).It was found that the CTM had experienced significant warming and wetting from 1961 to 2014,and will also experience warming in the future(2021-2100).Substantial warming in 1997 was captured by both the CN05.1 derived from interpolating meteorological station data and the multi-model ensemble(MME)from the CMIP6 *** MME simulation results indicated an apparent wetting in 2008,which occurred later than the wetting observed from the CN05.1 in *** GCMs generally underestimated spring temperature and overestimated both winter temperature and spring precipitation in the *** and wetting are more rapid in the northern part of the *** the end of the 21st century,all the four SSP scenarios project warmer and wetter conditions in the CTM with multiple dry-wet ***,the rise in precipitation fails to counterbal

关键词： climate change Coupled Model Intercomparison Project Phase 6(CMIP6) global climate models(GCMs) shared socio-economic pathway(SSP)scenarios standardized precipitation index(SPI) Chinese Tianshan Mountains

Effect of Ball Milling Time on Microstructure and Hydrogen Storage Properties of Nd5Mg41Ni Alloy

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Acta Metallurgica Sinica(English Letters) 2024年第7期37卷 1201-1214页

作者： Zeming Yuan Chenxu Liu Xiaoming Li Yongqi Sui Zhonggang Han Tingting Zhai Dianchen Feng Yanghuan Zhang Instrumental analysis center Inner Mongolia University of Science and TechnologyBaotou014010China Department of Functional Material Research Central Iron and Steel Research InstituteBeijing100081China

Mg-based alloys must be dehydrogenated at high pressure and temperatures, limiting their practical application. In this paper, Nd_(5)Mg_(41)Ni alloy was prepared by vacuum melting, and the as-cast alloy was ball milled for 5 h, 10 h, 15 h, and 20 h. The effect of ball milling time on the microstructure and hydrogen storage properties of the alloy was systematically studied. The alloy comprises Nd_(5)Mg_(41), NdMg_(12), NdMg_(3), and Mg_(2)Ni phases. The Nd_(5)Mg_(41)Ni alloy milling for 10 h can reach 95% of the saturated hydrogen absorption at 553 K by 40 s, and the alloy can desorb hydrogen only by 20 min. The dehydrogenation activation energy is only 99.9 kJ/mol H_(2). Ball milling makes the alloy produce many nanocrystalline and amorphous structures. The nano-grain boundary provides a channel for the diffusion of hydrogen atoms, and the high energy at the grain boundary provides energy for the phase deformation nucleus. Ball milling leads to the refinement of alloy particles and shortens the diffusion distance of hydrogen atoms to the interior of alloy particles. Defects such as twins and dislocations generated by milling provide energy for the phase deformation nucleus during the hydrogen absorption and desorption.

关键词： Hydrogen storage materials Magnesium-base alloy Ball milling Nanocrystal Kinetics