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Stereoselective recognition of morphine enantiomers by μ-opioid receptor

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National Science Review 2024年第3期11卷 183-191页

作者： Yibo Wang van A.ngo Xiaohui Wang Laboratory of Chemical Biology Changchun Institute of Applied ChemistryChinese Academy of Sciences Advanced Computing for Life Sciences and Engineering Group Science Engagement Section National Center for Computational Sciences Oak Ridge National Lab School of Applied Chemistry and Engineering University of Science and Technology of China Beijing National Laboratory for Molecular Sciences

Stereospecific recognition of chiral molecules plays a crucial role in biological systems. The μ-opioid receptor（MOR） exhibits binding affinity towards（-）-morphine, a well-established gold standard in pain management, while it shows minimal binding affinity for the（+）-morphine enantiomer, resulting in a lack of analgesic activity. Understanding how MOR stereoselectively recognizes morphine enantiomers has remained a puzzle in neuroscience and pharmacology for over half-a-century due to the lack of direct observation techniques. To unravel this mystery, we constructed the binding and unbinding processes of morphine enantiomers with MOR via molecular dynamics simulations to investigate the thermodynamics and kinetics governing MOR's stereoselective recognition of morphine enantiomers. Our findings reveal that the binding of（-）-morphine stabilizes MOR in its activated state, exhibiting a deep energy well and a prolonged residence time. In contrast,（+）-morphine fails to sustain the activation state of ***, the results suggest that specific residues, namely D1142.50and D1473.32, are deprotonated in the active state of MOR bound to（-）-morphine. This work highlights that the selectivity in molecular recognition goes beyond binding affinities, extending into the realm of residence time.

关键词： stereoselective recognition thermodynamics and kinetics residence time morphine enantiomers μ-opioid receptor

Optimization of Bow Shape for a Non Ballast Water Ship

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Journal of Marine Science and Application 2013年第3期12卷 251-260页

作者： ngo van he Yoshiho Ikeda Marine System Engineering Osaka Prefecture UniversityOsaka 599-8531 Japan

In this research,a commercial CFD code ＂Fluent＂ was applied to optimization of bulbous bow shape for a non ballast water ships（NBS）.The ship was developed at the Laboratory of the authors in Osaka Prefecture University,*** first,accuracy of the CFD code was validated by comparing the CFD results with experimental results at towing tank of Osaka Prefecture *** the optimizing process,the resistances acting on ships in calm water and in regular head waves were defined as the object *** features of bulbous bow shapes were considered as design parameters： volume of bulbous bow,height of its volume center,angle of bow bottom,and length of bulbous *** referring to the computed results given by the CFD like resistance,pressure and wave pattern made by ships in calm water and in waves,an optimal bow shape for ships was discovered by comparing the results in the series of bow *** the computation on waves,the ship is in fully captured condition because shorter waves,λ/Lpp 0.6,are assumed.

关键词： CFD bulbous bow non ballast water ships resistance

A Study on Effects of Blade Pitch on the Hydrodynamic Performances of a Propeller by Using CFD

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Journal of Shipping and Ocean Engineering 2018年第1期8卷 36-42页

作者： NGUYEN Chi Cong LUONG ngoc Loi ngo van he Vietnam Marine University Haiphong 180000 Vietnam Hanoi University of Science and Technology Hanoi 10000 Vietnam

The main objective of this work is to use the CFD （Computational Fluid Dynamics） technique to study the effects of pitch ratio on the controllable pitch propeller＇s thrust characteristic. The propeller analyzed is at the following design condition： diameter of 3.65 m, speed of 200 rpm, blade number of 4, average pitch of 2.459 m, pitch ratio at 0.7 of 0.6737. The first stage involves the mesh generation and refinement on domain of the designed propeller. The second stage deals with the identification of initial and boundary conditions of the mesh-equipped module. In the final stage, various results are calculated and analyzed for pitch ratio affecting on the propeller＇s thrust characteristic. The achieved results are the basis design and improving efficiency of the controllable pitch propeller.

关键词： Controllable pitch propeller propeller blade pitch ship CFD thrust.

Room-temperature ferroelectricity in van der Waals SnP_(2)S_(6)

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Frontiers of physics 2024年第4期19卷 113-123页

作者： Chaowei he Jiantian Zhang Li Gong Peng Yu State Key Laboratory of Optoelectronic Materials and Technologies Guangzhou Key Laboratory of Flexible Electronic Materials and Wearable Devices Nanotechnology Research Center School of Materials Science and EngineeringSun Yat-sen UniversityGuangzhou 510275China Instrumental Analysis and Research Center Sun Yat-sen UniversityGuangzhou 510275China

Two-dimensional(2D)ferroelectric materials,which possess electrically switchable spontaneous polarization and can be easily integrated with semiconductor technologies,is of utmost importance in the advancement of high-integration low-power *** the experimental discovery of certain 2D ferroelectric materials such as CuInP2S6 and In2Se3,achieving stable ferroelectricity at room temperature in these materials continues to present a significant ***,stable ferroelectric order at room temperature in the 2D limit is demonstrated in van der Waals SnP_(2)S_(6) atom layers,which can be fabricated via mechanical exfoliation of bulk SnP_(2)S_(6) *** polarization is observed in thin SnP_(2)S_(6) of~7 ***,a van der Waals ferroelectric field-effect transistor(Fe-FET)with ferroelectric SnP_(2)S_(6) as top-gate insulator and ptype WTe0.6Se1.4 as the channel was designed and fabricated successfully,which exhibits a clear clockwise hysteresis loop in transfer characteristics,demonstrating ferroelectric properties of SnP_(2)S_(6) atomic *** addition,a multilayer graphene/SnP_(2)S_(6)/multilayer graphene van der Waals vertical heterostructure phototransistor was also fabricated successfully,exhibiting improved optoelectronic performances with a responsivity(R)of 2.9 A/W and a detectivity(D)of 1.4×10^(12) *** results show that SnP_(2)S_(6) is a promising 2D ferroelectric material for ferroelectric-integrated low-power 2D devices.

关键词： two-dimensional ferroelectric materials ferroelectric fieldeffect transistors photodetectors

Optoelectronic Synapses Based on MXene/Violet Phosphorus van der Waals heterojunctions for Visual‑Olfactory Crossmodal Perception

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Nano-Micro Letters 2024年第6期16卷 38-52页

作者： Hailong Ma Huajing Fang Xinxing Xie Yanming Liu he Tian Yang Chai Center for Advancing Materials Performance From the Nanoscale(CAMP‑Nano) State Key Laboratory for Mechanical Behavior of MaterialsXi’an Jiaotong UniversityXi’an 710049People’s Republic of China Institute of Microelectronics and Beijing National Research Center for Information Science and Technology(BNRist) Tsinghua UniversityBeijing 100084People’s Republic of China Department of Applied Physics The Hong Kong Polytechnic UniversityHong KongPeople’s Republic of China

The crossmodal interaction of different senses,which is an important basis for learning and memory in the human brain,is highly desired to be mimicked at the device level for developing neuromorphic crossmodal perception,but related researches are ***,we demonstrate an optoelectronic synapse for vision-olfactory crossmodal perception based on MXene/violet phosphorus(VP)van der Waals *** from the efficient separation and transport of photogenerated carriers facilitated by conductive MXene,the photoelectric responsivity of VP is dramatically enhanced by 7 orders of magnitude,reaching up to 7.7 A W^(−1).Excited by ultraviolet light,multiple synaptic functions,including excitatory postsynaptic currents,pairedpulse facilitation,short/long-term plasticity and“learning-experience”behavior,were demonstrated with a low power ***,the proposed optoelectronic synapse exhibits distinct synaptic behaviors in different gas environments,enabling it to simulate the interaction of visual and olfactory information for crossmodal *** work demonstrates the great potential of VP in optoelectronics and provides a promising platform for applications such as virtual reality and neurorobotics.

关键词： Violet phosphorus MXene van der Waals heterojunctions Optoelectronic synapses Crossmodal perception

Tunable quantum anomalous Hall effects in ferromagnetic van der Waals heterostructures

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National Science Review 2024年第3期11卷 100-107页

作者： Feng Xue Yusheng Hou Zhe Wang Zhiming Xu Ke he Ruqian Wu Yong Xu Wenhui Duan Beijing Academy of Quantum Information Sciences State Key Laboratory of Low Dimensional Quantum Physics Department of Physics Tsinghua University Guangdong Provincial Key Laboratory of Magnetoelectric Physics and Devices Center for Neutron Science and Technology School of Physics Sun Yat-sen University State Key Laboratory of Surface Physics Key Laboratory of Computational Physical Sciences and Department of PhysicsFudan University Frontier Science Center for Quantum Information Department of Physics and Astronomy University of California-Irvine Tencent Quantum Laboratory Tencent Technology(Shenzhen)Co.Ltd RIKEN Center for Emergent Matter Science(CEMS) Institute for Advanced Study Tsinghua University

The quantum anomalous Hall effect（QAhe） has unique advantages in topotronic applications, but it is still challenging to realize the QAhe with tunable magnetic and topological properties for building functional devices. Through systematic first-principles calculations, we predict that the in-plane magnetization induced QAhe with Chern numbers C = ±1 and the out-of-plane magnetization induced QAhe with high Chern numbers C = ±3 can be realized in a single material candidate, which is composed of van der Waals（vdW）coupled Bi and MnBi2Te4monolayers. The switching between different phases of QAhe can be controlled in multiple ways, such as applying strain or（weak） magnetic field or twisting the vdW materials. The prediction of an experimentally available material system hosting robust, highly tunable QAhe will stimulate great research interest in the field. Our work opens a new avenue for the realization of tunable QAhe and provides a practical material platform for the development of topological electronics.

关键词： quantum anomalous Hall effect topological quantum phase transition van der Waals heterostructures tunable Chern number high Chern number

Nonlocal isogeometric analysis for bidirectional functionally graded porous curved microbeams with arbitrary boundary conditions

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Acta Mechanica Sinica 2024年第8期40卷 194-218页

作者： Thu-Huong Nguyen Thi van Ke Tran van-Minh Phung van Hai Trinh Quoc Hoa Pham Faculty of Mechanical Engineering Hanoi University of IndustryHanoi100000Vietnam Faculty of Mechanical Engineering Le Quy Don Technical UniversityHanoi100000Vietnam Institute of Vehicle and Energy Engineering Le Quy Don Technical UniversityHanoi100000Vietnam Faculty of Engineering and Technology Nguyen Tat Thanh UniversityHo Chi Minh City700000Vietnam

This research aims to analyze the static bending and free vibration behaviors of bidirectional functionally graded porous(BFGP)curved microbeams with elastic boundary conditions resting on a Pasternak’s elastic foundation in a hygro-thermal *** analysis based on non-uniform rational B-splines,first-order shear deformation theory,nonlocal elasticity theory combined with the modified strain gradient theories,modified Timoshenko beam theory are formulated to depict bending and shear deformations of BFGP curved ***,because using the modified Timoshenko beam theory,this study removes the requirement for a shear correction factor and describes shear stress by zero at the upper and lower cross-sectional sites of the BFGP curved *** from traditional boundary conditions,where the beginning and end positions of a curved beam are connected by an elastic system of straight and torsion *** allows for greater flexibility in controlling the stiffness of the springs to obtain arbitrary *** assess the accuracy and convergence of the proposed approach,validation numerical examples were conducted in the various examples.

关键词： Bidirectional functionally graded porous material Elastic boundary condition Isogeometric analysis Curved microbeams Nonlocal elasticity theory Modified strain gradient theory

Study of relationship between motion of mechanisms in gas operated weapon and its shock absorber

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Defence Technology（防务技术） 2024年第3期33卷 42-54页

作者： Jiri Balla Roman Vitek Dung Nguyen van Zbynek Krist Hung Nguyen van Department of Weapons and Ammunition University of Defence BrnoCzech Republic Department of Weapons Le Quy Don Technical UniversityHanoiViet Nam Department of Design and Special Engineering Alexander Dubcek University of TrencinSlovakia

The article deals with the motion of the breech block carrier and the weapon casing of an automatic weapon mounted on a flexible carriage and the base of the *** works,which did not consider the dynamic properties of the base of the weapon,did not allow to reconcile the calculated and experimental results of the weapon casing displacement when shooting from firing *** the analysis of the motion of individual parts,the methods of mathematical modelling and firing experiments using a high-speed camera were *** show the best accord with experiment when modelling the system with 4 degrees of *** oscillation of the system regarding the movement of the breech block carrier and the weapon casing was investigated under changed conditions of rate of fire,the use of a muzzle brake and different types of shock *** velocities and displacements of the weapon casing and the breech block carrier at different values of the impulse of the gases to the breech block carrier were determined.

关键词： Shock absorber Gas-operated weapon Force-impulse diagram Recoil system Breech block carrier

Unveiling strain-enhanced moiréexciton localization in twisted van der Waals homostructures

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Nano Research 2024年第4期17卷 3245-3252页

作者： henry Rui he Haihong Zheng Biao Wu Shaofei Li Junnan Ding Zongwen Liu Jian-Tao Wang Anlian Pan Yanping Liu Institute of Quantum Physics School of PhysicsCentral South UniversityChangsha 410083China State Key Laboratory of Precision Manufacturing for Extreme Service Performance Central South UniversityChangsha 410083China School of Chemical and Biomolecular Engineering The University of SydneyNSW 2006Australia Beijing National Laboratory for Condensed Matter Physics Institute of PhysicsChinese Academy of SciencesBeijing 100190China College of Materials Science and Engineering Hunan UniversityChangsha 410082China State Key Laboratory of High-Performance Complex Manufacturing Central South UniversityChangsha 410083China Shenzhen Research Institute of Central South University Shenzhen 51800China

Moirésuperlattices,arising from the controlled twisting of van der Waals homostructures at specific angles,have emerged as a promising platform for quantum emission ***,the manipulation of strain provides a versatile strategy to finely adjust electronic band structures,enhance exciton luminescence efficiency,and establish a robust foundation for two-dimensional quantum light ***,the intricate interplay between strain and moirépotential remains partially ***,we introduce a meticulously designed fusion of strain engineering and the twisted 2L-WSe_(2)/2L-WSe_(2) homobilayers,resulting in the precise localization of moiré*** low-temperature photoluminescence spectroscopy,we unveil the emergence of highly localized moiré-enhanced emission,characterized by the presence of multiple distinct emission ***,our investigation demonstrates the effective regulation of moirépotential depths through strain engineering,with the potential depths of strained and unstrained regions differing by 91%.By combining both experimental and theoretical approaches,our study elucidates the complex relationship between strain and moirépotential,thereby opening avenues for generating strain-induced moiréexciton single-photon sources.

关键词： moirésuperlattices strain engineering moiréexcitons moirépotential