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Cerebral microvascular dysfunction and neurodegeneration in dementia

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Stroke & Vascular Neurology 2019年第2期4卷 105-107页

作者： feng han Key Laboratory of Cardiovascular and Cerebrovascular Medicine School of PharmacyNanjing Medical UniversityNanjingJiangsuChina

Maintaining normal learning and memory functions requires a high degree of coordination between neural and vascular *** and clinical studies have shown that brain microvasculature dysfunction activates inflammatory cells in the brain,leading to progressive neuronal loss and eventually *** review focuses on recent studies aimed at identifying the molecular events that link cerebral microvascular dysfunction to neurodegeneration,including oxidative/nitrosative stress,cellular metabolic dysfunction,inflammatory signalling and abnormal synaptic plasticity.A better understanding of the coupling between vasculature and brain neurons and how this coupling is disrupted under pathological conditions is of great significance in identifying new diagnostic and treatment targets for dementia for which no new drugs have been approved since 2003.

关键词： dysfunction drugs eventually

Stimuli-Responsive Interconversion between Poly-NHC-Based Organometallic Assemblies and Their Self-Aggregated Dimers

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Chinese Journal of Chemistry 2024年第22期42卷 2840-2844页

作者： Guang-feng Jin Ying-feng han Key Laboratory of Synthetic and Natural Functional Molecule of the Ministry of Education Xi'an Key Laboratory of Functional Supramolecular Structureand MaterialsCollege of Chemistry and Materials ScienceNorthwest UniversityXi'anShaanxi 710127China

Comprehensive Summary Poly-NHC-based organometallic assemblies 3-PF6,3-SbF6 and 3-OTf were obtained and verified by NMR spectroscopy,ESI mass spectrometry and single-crystal X-ray diffraction *** structural interconversion was observed between the poly-NHC-based organometallic assemblies and their self-aggregated dimers in solution affected by concentration,solvent and metal ion.1H NMR spectra of assembly 3-PF6 in CD3CN at different concentrations demonstrated controllable structural interconversion,and 19F NMR spectrum of assembly 3-PF6 at high concentration further evidenced the presence of the free hexafluorophosphate anion and encapsulated hexafluorophosphate anion for its two sets of *** addition,single-crystal X-ray diffraction analysis provided clear evidence that in the solid state,two assemblies 3-PF6 were vertically stuck,forming a self-aggregated dimer with an encapsulated hexafluorophosphate *** the reversible structural interconversion is beneficial for revealing the intrinsic nature on the atom level and paving the way to design the stimuli-responsive functional system.

关键词： N-Heterocyclic carbene Organometallic assemblies Self-aggregated dimer Stimuli-responsive Structural interconversion Concentrationl Solvent Metalion

Entanglement dynamics and transfer in a double Jaynes-Cummings model

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Chinese Science Bulletin 2010年第17期55卷 1758-1762页

作者： han feng Department of Physics Jining University Jining 273155 China

We study the entanglement dynamics for a double Jaynes-Cummings model where two entangled atoms A and B locally interact with independent cavities a and b, respectively, but there are no interactions between locations Aa and Bb. We point out that there exists a parameter range in which simultaneous pairwise entanglement sudden death (ESD) for remote parties, i.e. AB, ab, Ab and Ba, may occur. We show that during this simultaneous ESD period various multipartite entanglement can be created. Our results imply that the pairwise entanglement between two independent locations may be transferred into other multipartite forms which account for the correlations between the two independent locations.

关键词：纠缠原子双光子动力学 s模型转让相互作用参数范围突然死亡

A bifunctional MnO_x@PTFE catalytic membrane for efficient low temperature NO_x-SCR and dust removal

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Chinese Journal of Chemical Engineering 2020年第5期28卷 1260-1267页

作者： Shasha feng Mengdi Zhou feng han Zhaoxiang Zhong Weihong Xing State Key Laboratory of Materials-Oriented Chemical Engineering National Engineering Research Center for Special Separation MembraneNanjing Tech UniversityNanjing 210009China Nanjing Industrial Technology Research Institute of Membrane Material Co.Ltd. Nanjing 211100China

Low-temperature selective catalytic reduction of NOx combined with dust removal technique due to its energy conservation characteristic has been attracted much attention for fume *** this work,the MnOx wrapped PTFE membrane with efficient dust removal and low-temperature NH3-SCR has been prepared with a facile *** different crystal structures was uniformly grown around the PTFE fibrils through water *** flower-sphere-like MnOx@PTFE(O-MnOx@PTFE)and lamellar-interlaced ripple-like MnOx@PTFE(W-MnOx@PTFE)have large specific surface area which is favorable for enhancing catalytic ***,the uniformly wrapped W-MnOxaround the PTFE fibrils optimized the pore structure for ultrafine dust *** membrane can almost 100%reject particles that are smaller than 1.0μm with a low filtration ***,W-MnOx@PTFE with more surface chemisorbed oxygen has the best NO conversion efficiency of 100%at a comparatively low and wide activity temperature window of 160–210°C,which is far to the thermal limitation of the ***,this efficient and energy conserving membrane has a bright application prospects for tail gas treatment compared to the original treatment process.

关键词： MnO_x PTFE Catalytic membrane Low-temperature SCR

Interactive design computation-a case study on quantum design paradigm

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Frontiers of Architectural Research 2013年第2期2卷 252-262页

作者： han feng HyperBODY Faculty of Architecture Delft University of Technology Delft 2628 BL The Netherlands

The ever-increasing comptexity of design processes fosters novet design computation modets to be employed in architecturat research and design in order to facilitate accurate data processing and refined decision making. These computation modets have enabled designers to work with comptex geometry and numeric design constraints to explore a whole new design field that is impossibte to explore without computation techniques. However, most current design computation modets foUow an automation-oriented paradigm that only dear with strictty defined problem solving and optimization, but fail in estabtishing an intuitive and interactive communication with designers. This lack of interaction reads to an unconscious rejection of non-parameterizabte design factors, which, reduces design computation models to specific design probtem sotving toots instead of operating as active design partners. This paper presents a non-deterministic design computation modeling approach derived from a discussion on quantum design paradigm, which emptoys rear-time user interaction as the co-driver to evotve user＋computation driven informed design outputs. model; *** Tootset, developed and applied in A case study of such a design computation a QuantumPointCloud workshop, will be illustrated in this paper. Expanded discussions on fabrication optimization and construction techniques from the QPC workshop will be addressed to conclude a comprehensive report.

关键词： Interactive designcomputation modeking Quantum Paradigm Hotwire cutting Point cloud Design constraint

Singularity analysis for single gimbal control moment gyroscope system using space expansion method

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Chinese Journal of Aeronautics 2018年第4期31卷 782-794页

作者： Yunhua WU feng han Bing HUA Zhiming CHEN feng YU School of Astronautics Nanjing University of Aeronautics and Astronautics School of Astronautics Harbin Institute of Technology

Control Moment Gyroscope（CMG） is an effective candidate for agile satellites and large spacecraft attitude control because of its powerful torque amplification capability. The most serious situation, however, in using CMG is the inherent geometric singularity problem, where there＇s no torque output along a particular direction. Space expansion method has been proposed in this work for the singularity analysis. Based on inverse mapping transformation, an expanded Jacobian matrix which is a full rank square matrix is obtained. The singular angle sets of the 3-parallel cluster and pyramid cluster are distinguished using space expansion method. An effective hybrid steering strategy, able to deal with the elliptic singularity, is further proposed. Simulation results demonstrate the excellent performance of the proposed steering logic compared to the generalized singular robust logic and pseudo inverse logic in terms of energy consumption and torque error.

关键词： Agile spacecraft Control moment gyro Singularity analysis Space expansion method Steering strategy

Rational tuning of thorium-organic frameworks by reticular chemistry for boosting radionuclide sequestration

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Nano Research 2022年第2期15卷 1472-1478页

作者： han feng Xiaohong Xiong Lele Gong Huiping Zhang Ying Xu Xuefeng feng feng Luo School of Chemistry Biology and Materials ScienceEast China University of TechnologyNanchang 330013China

The reticular chemistry strategy presents a powerful molecule-design tool to tailor the physical and chemical properties of metal-organic framework(MOF).In this work,we for the first time investigated the effect of organic ligands on the radionuclide sequestration(TcO_(4)^(-))of thorium-organic *** a coordination modulation technique,two novel isoreticular thorium-organic frameworks,namely Th-MOF-67 and Th-MOF-68,were *** to the antetype MOF of Th-MOF-66 that shows extremely low uptake of ReO_(4)^(-)(a chemical surrogate of radioactive TcO_(4)^(-)),the isoreticular MOFs of Th-MOF-67 and Th-MOF-68 enable ultrahigh uptake of ReO_(4)^(-),giving an impressively 36.8-fold or 56-fold enhancement,*** adsorption capacity of Th-MOF-68 is as high as 560 mg/g,exceeding most reported adsorbents for such *** mechanism for such exceptional outstanding performance,as unveiled by both the single crystal X-ray diffraction and theoretical calculation,is due to coordination interaction for Th-MOF-67,when a tetrazolate ligand was used,or a combined effect from both coordination interaction and anion-exchange for Th-MOF-68,if using a triazolate ligand.

关键词： thorium-organic framework ligand effect defect site anion exchange radionuclide sequestration

Arsenite oxidation by three types of manganese oxides

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Journal of Environmental Sciences 2006年第2期18卷 292-298页

作者： feng Xiong-han ZU Yan-qun TAN Wen-feng LIU Fan College of Resources and Environment Huazhong Agricultural University Wuhan 430070 China College of Resources and Environment Yunnan Agricultural University Kunming 650201 China

Oxidation of As（Ⅲ） by three types of manganese oxides and the effects ofpH, ion strength and tartaric acid on the oxidation were investigated by means of chemical analysis, equilibrium redox, X-ray diffraction （XRD） and transmission electron microscopy （TEM）. Three synthesized Mn oxide minerals, bimessite, cryptomelane, and hausmannite, which widely occur in soil and sediments, could actively oxidize As（Ⅲ） to As（Ⅴ）. However, their ability in As（Ⅲ）-oxidation varied greatly depending on their structure, composition and surface properties. Tunnel structured cryptomelane exhibited the highest ability of As （Ⅲ） oxidation, followed by the layer structured birnessite and the lower oxide hausmannite. The maximum amount of As （Ⅴ） produced by the oxidation was in the order （mmol/kg） of cryptomelane （824.2）〉 bimessite （480.4）〉 hausmannite （117.9）, As pH increased from the very low value（pH 2.5）, the amount of As（Ⅲ） oxidized by the tested Mn oxides was firstly decreased, then negatively peaked in pH 3.0 6.5, and eventually increased remarkably. Oxidation of As（Ⅲ） by the Mn oxides had a buffering effects on the pH variation in the solution. It is proposed that the oxidative reaction processes between As （Ⅲ） and biruessite（or cryptomelane） are as follows：（1） at lower pH condition：（MnO2）x＋ H3AsO3 ＋ 0.5H^＋=0.5H2AsO4^- ＋ 0.5HAsO4^2- ＋Mn〉^2＋（MnO2）x-1 ＋ H2O; （2） at higher pH condition：（MnO2）x ＋ H3AsO3 = 0.5H2AsO4^- ＋ 0.5HAsO4^2- ＋ 1.5H^＋＋（MnO2）x-1. MnO. With increase of ion strength, the As（Ⅲ） oxidized by bimessite and cryptomelane decreased and was negatively correlated with ion strength. However, ion strength had little influence on As （Ⅲ） oxidation by the hausmarmite. The presence of tartaric acid promoted oxidation of As（Ⅲ） by birnessite. As for cryptomelane and hansmannite, the same effect was observed when the concentration of tartaric acid was below 4 mmol/L, otherwise the oxidized As（Ⅲ） decreased. These findings are of great significance in improving our understanding

关键词： oxidation of As(Ⅲ) As(Ⅴ) Mn oxides pH ion strength tartaric acid

An optimized time-adaptive aerothermal coupling calculation method for aerothermal analysis of disc cavity system

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Chinese Journal of Aeronautics 2024年第9期37卷 164-177页

作者： Shuai BI Junkui MAO Lei WANG feng han College of Energy and Power Engineering Nanjing University of Aeronautics and AstronauticsNanjing 20016China AECC Aeroengine Control System Institute Wuxi 214063China Integrated Energy Institute Nanjing University of Aeronautics and AstronauticsNanjing 210016China

In order to further achieve the balance between the calculation accuracy and efficiency of the transient analysis of the aero-engine disc cavity system,an Optimized Time-adaptive Aerother-mal Coupling calculation(OTAC)method has been *** combines one-dimensional tran-sient calculation of air system,Conventional Sequence Staggered(CSS)method,Time-adaptive Aerothermal Coupling calculation(TAC)method and differential evolution optimization algorithm to obtain an efficient and high-precision aerothermal coupling calculation method of air *** both the heat conduction in the solid domain and the flow in the fluid domain as unsteady states in the OTAC,the interaction of fluid-solid information within a single coupling time step size was implemented based on the CSS ***,the coupling time step size was automatically adjusted with the number of iterations by using the Proportional-Integral-Deri vative(PID)*** show that when compared with the traditional loosely coupling method with a fixed time step size,the computational accuracy and efficiency of the OTAC method are improved by 8.9%and 30%,*** with the tight coupling calculation,the OTAC method can achieve a speedup of 1 to 2 orders of magnitude,while the calculation error is maintained within 6.1%.

关键词： Air system 1D-3D coupling Conjugate heat transfer Transient calculation Adaptive time step size