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EFFECT OF PRECIPITANT ON THE PROPERTIES OF ULTRAFINE YTTRIA POWDER PRODUCED BY PRE CIPITATION mETHOD

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Acta metallurgica Sinica(English Letters) 1999年第5期12卷 1188-1193页

作者： Y. Q. Jia1) , J. G. Li1) , Y. m. Wang2) , L. x. ding2) , x. m . Qin1) and x. D. Sun1)1) School of materials and metallurgy , Northeastern University , Shenyang 110006 , China2) Department of materials , School of mechanical Engineering , She

Using yttriu m nitrate as the m other salt , synthesis of ultrafine yttria po w der through w et che mical route w as investigated . Choice of precipitant has dra m atic effects on co m position ,particle size distribution and particle m orphology of the precipitates . When a m m onia solutionw as used as the precipitant , the precursor precipitate w as m ainly Y2( O H) 5 14( N O3) 0 86· H2 O with co m paratively large particle size , broad size distribution and co m plex particleshapes . When sodiu m hydroxide solution w as used , roughly spherical α Y( O H)3·3 H2 Opre cipitate w ith sm all particle size and narro w size distribution w as obtained . The transfor m a tion sequence of dry α Y( O H)3 ·3 H2 O gel during calcination w as determ ined to be α Y( O H) 3·3 H2 O→ Y O O H→ Y2 O3 . After calcining at 600 ℃ for 1 hour , both Y2( O H) 5 14( N O3) 0 86· H2 O and α Y( O H) 3·3 H2 O transfor m to well crystallized Y2 O3 pow ders ,w ith particle sizes of 50 ～3000 n m and 20 n m , respectively .

关键词： KEYW ORDS yttria ultrafine pow der synthesis w et che mical route

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 239 kA/*** addition,the composite exhibits a large saturation magnetostrictionλ_Ⅱover1200 ppm from 300 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

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

Self‑Healing Dynamic Hydrogel microparticles with Structural Color for Wound management

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Nano-micro Letters 2024年第11期16卷 177-190页

作者： Li Wang xiaoya ding Lu Fan Anne m.Filppula Qinyu Li Hongbo Zhang Yuanjin Zhao Luoran Shang Department of General Surgery Ruijin HospitalShanghai Jiaotong University School of MedicineShanghai 200025People’s Republic of China Department of Rheumatology and Immunology Nanjing Drum Tower HospitalSchool of Biological Science and Medical EngineeringSoutheast UniversityNanjing 210096People’s Republic of China Pharmaceutical Sciences Laboratory Åbo Akademi University20520 TurkuFinland Oujiang Laboratory(Zhejiang Lab for Regenerative medicine Vision and Brain Health)Wenzhou InstituteUniversity of Chinese Academy of SciencesWenzhou 325001People’s Republic of China Shanghai xuhui Central Hospital Zhongshan‑Xuhui Hospitaland the Shanghai Key Laboratory of Medical Epigeneticsthe International Co‑laboratory of Medical Epigenetics and Metabolism(Ministry of Science and Technology)Institutes of Biomedical SciencesFudan UniversityShanghai 200032People’s Republic of China

Chronic diabetic wounds confront a significant medical challenge because of increasing prevalence and difficult-healing *** is vital to develop multifunctional hydrogel dressings,with well-designed morphology and structure to enhance flexibility and effectiveness in wound *** achieve these,we propose a self-healing hydrogel dressing based on structural color microspheres for wound *** microsphere comprised a photothermal-responsive inverse opal framework,which was constructed by hyaluronic acid methacryloyl,silk fibroin methacryloyl and black phosphorus quantum dots(BPQDs),and was further re-filled with a dynamic *** dynamic hydrogel filler was formed by Knoevenagel condensation reaction between cyanoacetate and benzaldehyde-functionalized dextran(DEx-CA and DEx-BA).Notably,the composite microspheres can be applied arbitrarily,and they can adhere together upon near-infrared irradiation by leveraging the BPQDs-mediated photothermal effect and the thermoreversible stiffness change of dynamic ***,eumenitin and vascular endothelial growth factor were co-loaded in the microspheres and their release behavior can be regulated by the same ***,effective monitoring of the drug release process can be achieved through visual color *** microsphere system has demonstrated desired capabilities of controllable drug release and efficient wound *** characteristics suggest broad prospects for the proposed composite microspheres in clinical applications.

关键词： Black phosphorus Structural color Dynamic hydrogel Inverse opal Wound management

Analytical Expression for the Atomic Friction of a Single Asperity Based on the Prandtl-Tomlinson model

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Acta mechanica Solida Sinica 2024年第3期37卷 416-422页

作者： Weike Yuan Yue ding Gangfeng Wang xinrui Niu Department of Engineering mechanics SVLMMLXi’an Jiaotong UniversityXi’an710049China Department of mechanical Engineering City University of Hong KongHong Kong SAR999077China

The Prandtl-Tomlinson(PT)model has been widely applied to interpret the atomic friction mechanism of a single *** this study,we present an approximate explicit expression for the friction force in the one-dimensional PT model under quasi-static ***‘stick-slip’friction curves are first approximated properly by sawtooth-like lines,where the critical points before and after the‘slip’motion are described analytically in terms of a dimensionless parameterη.Following this,the average friction force is expressed in a closed form that remains continuous and valid forη>***,an analytical expression for the load dependence of atomic friction of a single asperity is derived by connecting the parameterηwith the normal *** the parameters reported in experiments,our prediction shows good agreement with relevant experimental results.

关键词： Atomic friction Stick-slip friction Prandtl-Tomlinson model Friction force microscope

The crosstalk between enteric nervous system and immune system in intestinal development,homeostasis and diseases

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Science China(Life Sciences) 2024年第1期67卷 41-50页

作者： xindi Wang Chenbo ding Hua-Bing Li Shanghai Institute of Immunology State Key Laboratory of Oncogenes and Related GenesShanghai Jiao Tong University School of MedicineShanghai 200025China Shanghai Jiao Tong University School of medicine-Yale Institute for Immune metabolism Shanghai Jiao Tong University School of MedicineShanghai 200025China

The gut is the largest digestive and absorptive organ,which is essential for induction of mucosal and systemic immune responses,and maintenance of metabolic-immune *** intestinal components contain the epithelium,stromal cells,immune cells,and enteric nervous system(ENS),as well as the outers,such as gut microbiota,metabolites,and *** dyshomeostasis of intestinal microenvironment induces abnormal intestinal development and functions,even colon diseases including dysplasia,inflammation and *** recent studies have identified that ENS plays a crucial role in maintaining the immune homeostasis of gastrointestinal(GI)*** crosstalk between ENS and immune cells,mainly macrophages,T cells,and innate lymphoid cells(ILCs),has been found to exert important regulatory roles in intestinal tissue programming,homeostasis,function,and *** this review,we mainly summarize the critical roles of the interactions between ENS and immune cells in intestinal homeostasis during intestinal development and diseases progression,to provide theoretical bases and ideas for the exploration of immunotherapy for gastrointestinal diseases with the ENS as potential novel targets.

关键词： enteric nervous system macrophages T cells innate lymphoid cells neuro-immune interactions

Optical system for extremely large spectroscopic survey telescope

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Science China(Physics,mechanics & Astronomy) 2024年第7期67卷 158-174页

作者： ding-qiang Su Hua Bai xiangyan Yuan xiangqun Cui Key Laboratory of the ministry of Education School of Astronomy and Space ScienceNanjing UniversityNanjing 210023China Nanjing Institute of Astronomical Optics and Technology(NIAOT) Chinese Academy of SciencesNanjing 210042China University of Chinese Academy of Sciences Nanjing 211135China School of Astronomy and Space Science University of Chinese Academy of SciencesBeijing 101408China

This article presents research work on a spectroscopic survey *** idea is as follows:for such a telescope,a pure reflecting optical system is designed,which should have an aperture and a field of view(FOV)both as large as possible and excellent image quality,and then a strip lensm(lens-prism)atmospheric dispersion corrector(S-ADC)is added,only for correcting the atmospheric *** the fund limitation and the simplicity of scaling up,some 12-m telescopes are designed as ***,Korsch,and meinel put forward the four-mirror Nasmyth systems I and II,which are used in this *** of 1.5°,2°,and 2.5°are *** all systems,the image qualities are *** the S-ADC relaxes the optical glass size restriction,this 12-m telescope with a FOV of 2.5°can be magnified in proportion to a 16-m *** etendue(from Frenchétendue)and focal surface will now be the largest in the *** such a telescope,a pure reflecting optical system can also be obtained.A subsequent coudésystem is designed with excellent image quality.

关键词： telescopes spectroscopic survey

Numerical analysis of geosynthetic-reinforced embankment performance under moving loads

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Journal of Rock mechanics and Geotechnical Engineering 2024年第2期16卷 682-696页

作者： xuanming ding Jinqiao Zhao Qiang Ou Jianfei Liu College of Civil Engineering Chongqing UniversityChongqing400045China Key Laboratory of New Technology for Construction of Cities in mountain Area Chongqing UniversityChongqing400045China China United Engineering Corporation Limited Hangzhou310052China

The performance of geosynthetic-reinforced embankments under traffic moving loads is always a hotspot in the geotechnical engineering field.A three-dimensional(3D)model of a geosynthetic-reinforced embankment without drainage consolidation was established using the finite element software *** this model,the traffic loads were simulated by two moving loads of rectangular pattern,and their amplitude,range,and moving speed were realized by a Fortran *** embankment fill was simulated by an equivalent linear viscoelastic model,which can reflect its *** geogrid was simulated by the truss element,and the geocell was simulated by the membrane *** elements were utilized to weaken the boundary effect caused by the model geometry at the *** of the established numerical model was conducted by comparing the predicted deformations in the cross-section of the geosynthetic-reinforced embankment with those from the existing *** this basis,the dynamic stress and strain distribution in the pavement structure layer of the geosynthetic-reinforced embankment under a moving load was also ***,a parametric study was conducted to examine the influences of the different types of reinforcement,overload,and the moving load velocity on the geosynthetic-reinforced embankment.

关键词： Geosynthetic-reinforced layer Numerical model moving load Embankment Deformation Stress

Long way up:rethink diseases in light of phase separation and phase transition

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Protein & Cell 2024年第7期15卷 475-492页

作者： mingrui ding Weifan xu Gaofeng Pei Pilong Li State Key Laboratory of membrane Biology&Frontier Research Center for Biological Structure School of Life SciencesTsinghua UniversityBeijing 100084China Tsinghua-Peking Center for Life Sciences Beijing 100084China NuPhase Therapeutics Beijing 100083China

Biomolecular condensation, driven by multivalency, serves as a fundamental mechanism within cells, facilitating the formation of distinct compartments, including membraneless organelles that play essential roles in various cellular processes. Perturbations in the delicate equilibrium of condensation, whether resulting in gain or loss of phase separation, have robustly been associated with cellular dysfunction and physiological disorders. As ongoing research endeavors wholeheartedly embrace this newly acknowledged principle, a transformative shift is occurring in our comprehension of disease. Consequently, significant strides have been made in unraveling the profound relevance and potential causal connections between abnormal phase separation and various diseases. This comprehensive review presents compelling recent evidence that highlight the intricate associations between aberrant phase separation and neurodegenerative diseases, cancers, and infectious diseases. Additionally, we provide a succinct summary of current efforts and propose innovative solutions for the development of potential therapeutics to combat the pathological consequences attributed to aberrant phase separation.

关键词： multivalency compartments aberant phase separation therapeutics gain or loss of phase separation diseases