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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2024年第3期25卷 268-274页

作者： Jjijie YE xuan xu Chuande WU Department of Chemistry Zhejiang UniversityHangzhou 310058China

Three polyoxometalate-based hybrid coordination materials,[Co_(8)(H_(2)O)_(34)(pz)_(2){Co_(4)(H_(2)O)_(2)P_(4)W_(30)O_(112)}]·16H_(2)O(compound 1),[H_(3)O]_(4)[Co_(6)(H_(2)O)_(22)(pz)_(2){Co_(4)(H_(2)O)_(2)P_(4)W_(30)O_(112)}]·21H_(2)(compound 2),and[H_(3)O]_(4)[Co_(6)(H_(2)O)_(22){Co_(4)(H_(2)O)_(2)P_(4)W_(30)O_(112)}]·29H_(2)O(compound 3)(pz-pyrazine),were built from the linkage of[Co_(4)(H_(2)O)_(2)(P_(2)W_(15)O_(56)_(2)]^(16-)-(abbreviated as{Co_(4)P_(4)W_(30})polyanions and pz and/or cobalt(II)cations.Although compounds 1 and 2 consisted of the same components,their lamellar networks were quite different.The inorganic lamellar network in compound 3 was constructed by connecting{Co_(4)P_(4)W_(30)}units with cobalt(I)cations.This work demonstrates that the coordination modes of{Co_(4)P_(4)W_(30)}are very sensitive to synthesis conditions,while the ring-belt tetrametals are easily substituted by different transition metal cations under mild reaction conditions.

关键词： Cobalt Crystal structure Cyclic voltammetry Hybrid Polyoxometalate

From charge storage mechanism to performance:A strategy toward boosted lithium/sodium storage through heterostructure optimization

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Journal of Energy Chemistry 2024年第1期88卷 112-124,I0003页

作者： Xiaoke Zhang Guangfa Deng Mianying Huang Zhaohui xu Jianlin Huang xuan xu Zhiguang xu Maochan Li Lei Hu Xiaoming Lin Key Laboratory of Theoretical Chemistry of Environment Ministry of EducationSchool of ChemistrySouth China Normal UniversityGuangzhou 510006GuangdongChina Anhui Laboratory of Functional Coordinated Complexes for Materials Chemistry and Application School of Chemical and Environmental EngineeringAnhui Polytechnic UniversityWuhu 241000AnhuiChina National Engineering Research Center for Carbohydrate Synthesis Key Lab of Fluorine and Silicon for Energy Materials and Chemistry of Ministry of EducationJiangxi Normal UniversityNanchang 330022JiangxiChina

Solving the problems of low electrical conductivity and poor cycling durability in transition metal oxidesbased anode materials for lithium-ion batteries(LIBs)and sodium-ion batteries(SIBs)has already turned into an urgent requirement.In this paper,we successfully synthesized Co_(2)VO_(4)/Co compounds with Co-VMOF(metal-organic framework)as a sacrificial template and investigated their electrochemical mechanism in order to improve the electrochemical properties of LIBs and SIBs.The optimized heaping configuration and the existence of metallic Co catalyzed the formation of radical ions,thereby facilitating higher conductivity,shortening Li+and Na+transport paths,and providing more active sites.Co_(2)VO_(4)/Co constructed with 2-methylimidazole as a ligand showed a discharge capacity of 1605.1 mA h g^(-1)after 300 cycles at 0.1 A g^(-1)in LIB and 677.2 mA h g^(-1)in SIB.Density functional theory(DFT)calculation emphasizes the crucial role of Co_(2)VO_(4)/Co in enhancing electrode conductivity,decreasing the migratory energy barrier,and thereby strengthening electrochemical properties.This heterostructure building technique may pave the way for the development of high-performance LIBs and SIBs.Furthermore,the problem of the low first-loop coulombic efficiency faced by transition metal oxides is improved.

关键词： Metal-organic framework Heterostructure Lithium-ion batteries Sodium-ion batteries DFT calculation

Upadacitinib for refractory ulcerative colitis with primary nonresponse to infliximab and vedolizumab:A case report

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World Journal of Clinical Cases 2024年第9期12卷 1685-1690页

作者： xuan xu Jing-Wen Jiang Bing-Yun Lu Xia-Xi Li Department of Gastroenterology Shenzhen HospitalSouthern Medical UniversityShenzhen 518100Guangdong ProvinceChina The First Clinical Medical School Southern Medical UniversityGuangzhou 510515Guangdong ProvinceChina

BACKGROUND Many patients with ulcerative colitis(UC)do not respond well to,or tolerate conventional and biological therapies.There is currently no consensus on the treatment of refractory UC.Studies have demonstrated that the selective Janus kinase 1 inhibitor upadacitinib,a small-molecule drug,is effective and safe for treating UC.However,no studies have revealed that upadacitinib is effective in treating refractory UC with primary nonresponse to infliximab and vedolizumab.CASE SUMMARY We report the case of a 44-year-old male patient with a chief complaint of bloody diarrhoea with mucus and pus,in addition to dizziness.The patient had recurrent disease after receiving mesalazine,prednisone,azathioprine,infliximab and vedolizumab over four years.Based on the endoscopic findings and pathological biopsy,the patient was diagnosed with refractory UC.In particular,the patient showed primary nonresponse to infliximab and vedolizumab.Based on the patient’s history and recurrent disease,we decided to administer upadacitinib.During hospitalisation,the patient was received upadacitinib under our guidance.Eight weeks after the initiation of upadacitinib treatment,the patient’s symptoms and endoscopic findings improved significantly.No notable adverse reactions have been reported to date.CONCLUSION Our case report suggests that upadacitinib may represent a valuable strategy for treating refractory UC with primary nonresponse.

关键词： Upadacitinib Refractory ulcerative colitis Primary nonresponse Infliximab Vedolizumab Case report

Reversible Mn^(2+)/Mn^(4+)double-electron redox in P3-type layer-structured sodium-ion cathode

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Journal of Energy Chemistry 2024年第2期89卷 79-88,I0004页

作者： Jie Zeng Jian Bao Ya Zhang xun-Lu Li Cui Ma Rui-Jie Luo Chong-Yu Du xuan xu Zhe Mei Zhe Qian Yong-Ning Zhou Department of Materials Science Fudan UniversityShanghai 200433China Shanghai xuanyi New Energy Development Co. LtdShanghai 201800China Global Institute of Future Technology Shanghai Jiao Tong UniversityShanghai 200240China

The balance between cationic redox and oxygen redox in layer-structured cathode materials is an important issue for sodium batteries to obtain high energy density and considerable cycle stability.Oxygen redox can contribute extra capacity to increase energy density,but results in lattice instability and capacity fading caused by lattice oxygen gliding and oxygen release.In this work,reversible Mn^(2+)/Mn^(4+)redox is realized in a P3-Na_(0.65)Li_(0.2)Co_(0.05)Mn_(0.75)O_(2)cathode material with high specific capacity and structure stability via Co substitution.The contribution of oxygen redox is suppressed significantly by reversible Mn^(2+)/Mn^(4+)redox without sacrificing capacity,thus reducing lattice oxygen release and improving the structure stability.Synchrotron X-ray techniques reveal that P3 phase is well maintained in a wide voltage window of 1.5-4.5 V vs.Na^(+)/Na even at 10 C and after long-term cycling.It is disclosed that charge compensation from Co/Mn-ions contributes to the voltage region below 4.2 V and O-ions contribute to the whole voltage range.The synergistic contributions of Mn^(2+)/Mn^(4+),Co^(2+)/Co^(3+),and O^(2-)/(O_n)^(2-)redox in P3-Na_(0.65)Li_(0.2)Co_(0.05)Mn_(0.75)O_(2)lead to a high reversible capacity of 215.0 m A h g^(-1)at 0.1 C with considerable cycle stability.The strategy opens up new opportunities for the design of high capacity cathode materials for rechargeable batteries.

关键词： Sodium batteries Cathode materials Layered structure Co substitution

Pressure transient characteristics of non-uniform conductivity fractured wells in viscoelasticity polymer flooding based on oil-water two-phase flow

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Petroleum Science 2024年第1期21卷 343-351页

作者： Yang Wang Jia Zhang Shi-Long Yang Ze-xuan xu Shi-Qing Cheng National Key Laboratory of Petroleum Resources and Engineering China University of Petroleum(Beijing)Beijing102249China

Polymer flooding in fractured wells has been extensively applied in oilfields to enhance oil recovery.In contrast to water,polymer solution exhibits non-Newtonian and nonlinear behavior such as effects of shear thinning and shear thickening,polymer convection,diffusion,adsorption retention,inaccessible pore volume and reduced effective permeability.Meanwhile,the flux density and fracture conductivity along the hydraulic fracture are generally non-uniform due to the effects of pressure distribution,formation damage,and proppant breakage.In this paper,we present an oil-water two-phase flow model that captures these complex non-Newtonian and nonlinear behavior,and non-uniform fracture characteristics in fractured polymer flooding.The hydraulic fracture is firstly divided into two parts:high-conductivity fracture near the wellbore and low-conductivity fracture in the far-wellbore section.A hybrid grid system,including perpendicular bisection(PEBI)and Cartesian grid,is applied to discrete the partial differential flow equations,and the local grid refinement method is applied in the near-wellbore region to accurately calculate the pressure distribution and shear rate of polymer solution.The combination of polymer behavior characterizations and numerical flow simulations are applied,resulting in the calculation for the distribution of water saturation,polymer concentration and reservoir pressure.Compared with the polymer flooding well with uniform fracture conductivity,this non-uniform fracture conductivity model exhibits the larger pressure difference,and the shorter bilinear flow period due to the decrease of fracture flow ability in the far-wellbore section.The field case of the fall-off test demonstrates that the proposed method characterizes fracture characteristics more accurately,and yields fracture half-lengths that better match engineering reality,enabling a quantitative segmented characterization of the near-wellbore section with high fracture conductivity and the far-wellbore section with low fracture conduct

关键词： Polymer flooding Non-Newtonian fluid Non-uniform fracture conductivity Two-phase flow Pressure transient analysis

Factors affecting meibomian gland area loss in symptomatic adults

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International Journal of Ophthalmology(English edition) 2024年第6期17卷 1036-1041页

作者： Si-Cheng Ding Jing-Jing Su Qing Zhan Jiao-Man Wang Fang Zheng xu-xuan Fang Dan Cheng Ping Guo The Second Clinical Medical College Jinan UniversityShenzhen 518000Guangdong ProvinceChina Shenzhen Eye Hospital Jinan UniversityShenzhen Eye InstituteShenzhen 518040Guangdong ProvinceChina Department of Ophthalmology Jinzhou Medical UniversityJinzhou 121000Liaoning ProvinceChina

AIM:To characterize the distribution of meibomian gland(MG)area loss(MGL)and its relationship with demographic characteristics,mites,and symptoms.METHODS:This retrospective observational study included patients who visited the Dry Eye Clinic of Shenzhen Eye Hospital between June 2020 and August 2021.General patient characteristics,ocular symptoms,Demodex test results of the eyelid edges,and the results of a comprehensive ocular surface analysis were collected.MGL was analyzed using Image J software.RESULTS:This study enrolled 1204 outpatients aged 20-80(40.70±13.44)y,including 357 males(29.65%)and 847 females(70.35%).The patients were classified into mild(n=155;12.87%),moderate(n=795;66.03%),severe(n=206;17.11%),and extremely severe(n=48;3.99%)MGL groups.MGL was significantly larger in female than in male(P=0.006).The degree of MGL also significantly differed in age(P<0.001)and the more numbers of mites with severity(P<0.001).Multivariate disordered multinomial logistic regression analysis identified that female sex,older age,secretory symptoms,and a large number of mites were risk factors for MGL(P<0.05).CONCLUSION:Patients with MGL are more likely to be older,female,more numbers of mites,and increased secretion.

关键词： meibomianglands aging sex symptomatology Demodex

Snow Fun Beyond Harbin

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China News Release 2024年第2期 70-73页

作者： xu xuan 不详

This winter,Harbin in northeast China's Heilongjiang Province,as the forerunner of ice and snow tourism,has attracted many a tourist with its unique ice and snow views and vibrant cultural activities.On January 5,the 2024 China Ice and Snow Tourism Development Forum held in Harbin released a report on China's ice and snow tourism development,ranking Harbin as the top destination among the"Top 10 Cities for Ice and Snow Tourism in 2024."Other than Harbin,many ice and snow programs in other places have also garnered significant attention,beckoning travelers to explore their fun.

关键词： northeast winter tourism

Stable striped state in a rotating two-dimensional spin–orbit coupled spin-1/2 Bose–Einstein condensate

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Communications in Theoretical Physics 2022年第7期74卷 114-122页

作者： xuan xu Chao Gao Ji Lin Hui-jun Li Institute of Nonlinear Physics and Department of Physics Zhejiang Normal UniversityJinhua 321004China

We consider an effective two-dimensional Bose–Einstein condensate with some spin–orbit coupling(SOC) and a rotation term in an external harmonic potential. We find the striped state,and analyze the effects of SOC, the external potential, and the rotation frequency/direction on the profile and the stability of the striped state. Without the rotation term, the two spinor components exhibit striped pattern, and the numbers of stripes in the two components are always an odd–even or an even–odd. With the increase of the SOC strength, the number of stripes in both components increases, while the difference of the striped numbers is always one. After adding the rotation term, the profiles of the spinor components change qualitatively, and the change regulation of the striped numbers differs, while the difference of the striped numbers is still one. In addition, we find that the rotation direction only makes the striped state of the two spinor components exchange each other, though the clockwise and counterclockwise rotation directions are inequivalent with the presence of SOC. Such regulation is different from the previous study. And the rotation frequency gives rise to the transition from the striped state to a mixture of the striped state and vortex state. Furthermore, we prove the stability of these states by the evolution and linear stability analysis.

关键词： spin-orbit coupling Bose-Einstein condensate the striped state

Trimetallic Metal-Organic Framework Nanoframe Superstructures: A Stress-Buffering Architecture Engineering of Anode Material toward Boosted Lithium Storage Performance

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Energy & Environmental Materials 2023年第1期6卷 289-299页

作者： Jia Lin Chao xu Man Lu Xiaoming Lin Zeeshan Ali Chenghui Zeng xuan xu and Yifan Luo Key Laboratory of Theoretical Chemistry of Environment Ministry of EducationGuangzhou Key Laboratory of Materials for Energy Conversion and StorageSchool of ChemistrySouth China Normal UniversityGuangzhou 510006China School of Chemical and Materials Engineering(SCME) National University of Sciences and Technology(NUST)Islamabad 44000H-12Pakistan College of Chemistry and Chemical Engineering Key Laboratory of Functional Small Organic MoleculeMinistry of Education and Jiangxi’s Key Laboratory of Green ChemistryJiangxi Normal UniversityNanchang 330022China

Metal-organic frameworks(MOFs)can serve as prevailing anodes for lithium-ion batteries,due to their multiple redox-active sites and prominent structural compatibility.However,the poor electronic conductivity and inferior cyclability hinder their further implementation.Herein,a synthetic methodology for trimetallic Fe-Co-Ni MOFs with nanoframe superstructures architecture(Fe-Co-Ni NFSs)via structural evolution is proposed for versatile anode materials for lithium storage.Ascribed to optimal compositional and structural optimization,the Fe-Co-Ni NFSs achieve exceptional electrochemical performance with superior specific capacity(1030 mAh g^(−1) at 0.1 A g^(−1)),outstanding rate capacity(414 mAh g^(−1) at 2 A g^(−1)),and prolonged cyclability(489 mAh g^(−1) upon 1000 cycles at 1 A g^(−1)).Both experimental and theoretical investigations reveal that the multi-component metal centers could boost electronic conductivity,confer multiple active sites,and energetically favor Li adsorption capability.Additionally,the nanoframe superstructures of Fe-Co-Ni NFSs could facilitate stress-buffering effect on volumetric expansion and prevent electrode pulverization,further improving the lithium storage capability.This work envisions a meticulous protocol for high-performance MOF anode materials for lithium-ion batteries.

关键词： anode DFT calculation lithium storage stress-buffering architecture trimetallic metal-organic framework

Aid Rush in Quake-Hit Area

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China News Release 2024年第1期 32-33页

作者： xu xuan 不详

A 6.2-magnitude earthquake jolted Jishishan County of Linxia Hui Autonomous Prefecture in northwest China's Gansu Province at 11:59 p.***.on December 18,2023.The epicenter,with a depth of 10 kilometers,was monitored at 35.7 degrees north latitude and 102.79 degrees east longitude,causing damage to houses and infrastructure like water,electricity,transportation and communications in Gansu and neighboring Qinghai Province.

关键词： Province northwest Gansu