检索结果-南通市图书馆

Mott insulator-density ordered superfluid transition and‘shamrock transition’in a frustrated triangle lattice

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Communications in Theoretical Physics 2024年第3期76卷 157-164页

作者： ce wang Yu Chen School of Physics Science and Engineering Tongji UniversityShanghai200092China Institute for Advanced Study Tsinghua UniversityBeijing100084China Graduate School of China Academy of Engineering Physics Beijing100193China

Density order is usually a consequence of the competition between long-range and short-range *** we report a density ordered superfluid emergent from a homogeneous Mott insulator due to the competition between frustrations and local *** transition is found in a Bose–Hubbard model on a frustrated triangle lattice with an extra pairing ***,we find a quantum phase transition between two different density ordered superfluids,which is beyond the Landau–Ginzburg(LG)paradigm.A U(1)symmetry is emergent at the critical point,while the symmetry in each density ordered superfluid is Z_(2)×Z_(3).We call the transition a‘shamrock transition’,due to its degenerate ground state in the parameter space being a shamrock-like curve rather than a circle in an LG-type *** low energy theories are established for the two transitions mentioned above and we find their resemblance and differences with clock models.

关键词： frustrated magnets superfluid mott insulator density wave ordered phase clock model

Reinforcement Learning-Based Dynamic Order Recommendation for On-Demand Food Delivery

在线全文

学校读者我要写书评

暂无评论

Tsinghua Science and Technology 2024年第2期29卷 356-367页

作者： xing wang Ling wang Chenxin Dong Hao Ren Ke xing Department of Automation Tsinghua UniversityBeijing 100080China School of Mechanical and Automotive Engineering Qingdao Hengxing University of Science and TechnologyQingdao 266100China Meituan Beijing 100015China

On-demand food delivery(OFD)is gaining more and more popularity in modern *** a kernel order assignment manner in OFD scenario,order recommendation directly influences the delivery efficiency of the platform and the delivery experience of *** paper addresses the dynamism of the order recommendation problem and proposes a reinforcement learning solution *** actor-critic network based on long short term memory(LSTM)unit is designed to deal with the order-grabbing conflict between different ***,three rider sequencing rules are accordingly proposed to match different time steps of the LSTM unit with different *** test the performance of the proposed method,extensive experiments are conducted based on real data from Meituan delivery *** results demonstrate that the proposed reinforcement learning based order recommendation method can significantly increase the number of grabbed orders and reduce the number of order-grabbing conflicts,resulting in better delivery efficiency and experience for the platform and riders.

关键词： on-demand food delivery order recommendation reinforcement learning actor-critic network long short term memory

Tumor microenvironment-responsive arsenic-loaded layered double hydroxides film with synergistic anticancer and bactericidal activity

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Rare Metals 2024年第3期43卷 1207-1221页

作者： Shun xing Dong-Hui wang Hai-Feng Zhang Li-Dan Liu Cheng-ce Li Chao Wei Jun-Yu Liu Nai-Jian Ge Xuan-Yong Liu State Key Laboratory of High Performance ceramics and Superfine Microstructure Shanghai Institute of CeramicsChinese Academy of SciencesShanghai200050China center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing100049China Intervention center Eastern Hepatobiliary Surgery HospitalThe Third Affiliated Hospital of Naval Medical UniversityShanghai200438China School of Health Sciences and Biomedical Engineering Hebei University of TechnologyTianjin300130China

Malignant obstruction makes gallbladder cancer have a high mortality ***-titanium alloy(nitinol)stents are commonly used as a local intervention to maximize patient survival time,but the stents lack antitumor and antibacterial capacity and are vulnerable to secondary ***-based drugs show good therapeutic promise against gallbladder *** meet clinical *** layered double hydroxides(LDHs)film is constructed on the nitinol,whose arsenite loading amounts rose by 60%after simple heat treatment compared with the conventional anion-exchange *** addition,calcination promotes the dissolution of nickel ions from the LDHs lattice,resulting in a powerful synergistic killing effect on tumor cells together with the released *** importantly,the calcined arsenic-loaded LDHs are sensitive to the acidic microenvironment of tumor tissues,which presents a much lower arsenic and nickel release amount in the normal tissues,guaranteeing its ***,the vertically sharp LDHs nanosheets can synergize with arsenic to achieve effective physical cleavage and chemical killing of adherent and planktonic *** short,we attempt to use arsenic drugs for local interventions and reasonably avoid their toxic side effects,which provides a new design idea for nitinol stents applied in the treatment of gallbladder cancer.

关键词： Nitinol Layered double hydroxides Arsenic Gallbladder cancer

Applications of mercury stable isotopes for tracing volcanism in the geologic record

在线全文

学校读者我要写书评

暂无评论

Science China Earth Sciences 2024年第5期67卷 1436-1458页

作者： Qing GONG Ming-xing LING wang ZHENG State Key Laboratory of Nuclear Resources and Environment East China University of TechnologyNanchang 330013China School of Earth System Science Institute of Surface-Earth System ScienceTianjin UniversityTianjin 300072China

Mercury(Hg)enrichments in ancient sediments have been used as a proxy of volcanism,especially large igneous province(LIP)***,considering the existence of other potential Hg sources besides volcanoes and the diverse factors(e.g.,organic matters,clay minerals,sulfide minerals and Fe oxides)that can affect Hg sequestration,there are considerable uncertainties to simply regard sedimentary Hg anomalies as signatures of volcanic *** stable isotopes,a promising tool for tracing the origins and transformations of Hg,have been increasingly used for determining the causes of Hg spikes and understanding the geochemical behavior of Hg in the geologic *** date,lots of researches have applied Hg concentrations and Hg isotopes to identify LIP volcanisms linking with significant geological events such as mass extinctions,ocean anoxic events and other environmental perturbations that mainly occurred in the ***,the results in previous studies clearly show that not all Hg enrichments are derived from volcanic inputs,which emphasize the need for more caution in using Hg as a fingerprint of *** a better understanding of Hg isotopes in the future,there will be important implications for Hg isotopes to reconstruct volcanic activities in the rock records and their impacts on biological evolution.

关键词： Mercury stable isotopes Large igneous province Mass extinction event Ocean anoxic event

Resilient performance of self-centering hybrid rocking walls with curved interface under pseudo-static loading

在线全文

学校读者我要写书评

暂无评论

Earthquake Engineering and Engineering Vibration 2024年第1期23卷 65-85页

作者： Su xing Yan Shi Sun Xianglei wang Tao School of Civil Engineering Shenyang Jianzhu UniversityShenyang 110168China PetroChina East China Design Institute Co. Ltd.Qingdao 266000China Qingdao Country Garden Bolin Real Estate Co. Ltd.Qingdao 266100China

Frame and rocking wall(FRW)structures have excellent resilient performance during ***,the concrete at interfacial corners of rocking walls(RWs)is easily crushed due to local extreme compression during the rocking *** innovative RW with a curved interface is proposed to prevent interfacial corners from producing local damage,enhancing its earthquake resilient performance(ERP).The precast wall panel with a curved interface is assembled into an integral self-centering hybrid rocking wall(SCRW)by two post-tensioned unbonded prestressed ***,two ordinary energy dissipation steel rebars and two shear reinforcements are arranged to increase the energy dissipation capacity and lateral *** SCRW specimens and one monolithic reinforced concrete(RC)shear wall(SW)were tested under pseudo-static loading to compare the ERPs of the proposed SCRW and the SW,focusing on studying the effect of the curved interface on the *** key resilient performance of rocking effects,failure modes,and hysteretic properties of the SCRW were *** results show that nonlinear deformations of the SCRW are concentrated along the interface between the SCRW and the foundation,avoiding damage within the *** restoring force provided by the prestressed tendons can effectively realize self-centering capacity with small residual deformation,and the resilient performance of the SCRW is better than that of monolithic *** addition,the curved interface of the SCRW makes the rocking center change and move inward,partially relieving the stress concentration and crush of *** rocking range of the rocking center is about 41.4%of the width of the SCRW.

关键词： self-centering hybrid rocking wall(SCRW) monolithic shear wall(SW) earthquake resilient performance(ERP) curved interface rocking center

Optical third-harmonic generation of spherical quantum dots under inversely quadratic Hellmann plus inversely quadratic potential

在线全文

学校读者我要写书评

暂无评论

Communications in Theoretical Physics 2024年第9期76卷 158-163页

作者： xing wang Xuechao Li School of Mechanics and Photoelectric Physics Anhui University of Science and TechnologyHuainan 232001China

The third-harmonic generation(THG)coefficient for a spherical quantum dot system with inversely quadratic Hellmann plus inversely quadratic potential is investigated theoretically,considering the regulation of quantum size,confinement potential depth and the external *** numerical simulation results indicate that the THG coefficient can reach the order of 10~(-12)m~2V~(-2),which strongly relies on the tunable factor,with its resonant peak experiencing a redshift or ***,the effect of temperature on the THG coefficient in terms of peak location and size is consistent with the quantum dot radius but contrasts with the hydrostatic ***,it is crucial to focus on the influence of internal and external parameters on nonlinear optical effects,and to implement the theory in practical experiments and the manufacture of optoelectronic devices.

关键词： nonlinear optical effects quantum dot inversely quadratic hellmann potential inversely quadratic potential third harmonic generation coefficient

Functional microfluidics:theory,microfabrication,and applications

在线全文

学校读者我要写书评

暂无评论

International Journal of Extreme Manufacturing 2024年第3期6卷 140-173页

作者： Mingzhu Xie Ziheng Zhan Yinfeng Li Junkai Zhao ce Zhang Zhaolong wang Zuankai wang Interdisciplinary Research center of Low-carbon Technology and Equipment College of Mechanical and Vehicle EngineeringHunan UniversityChangsha 410082People’s Republic of China Energy Research Institute of Shandong Academy of Sciences Qilu University of Technology(Shandong Academy of Sciences)Jinan 250014People’s Republic of China Qian Xuesen Laboratory of Space Technology China Academy of Space Technology(CAST)Beijing 100094People’s Republic of China Department of Mechanical Engineering Hong Kong Polytechnic UniversityHong Kong Special Administrative Region of China 999077People’s Republic of China

Microfluidic devices are composed of microchannels with a diameter ranging from ten to a few hundred ***,quite a small(10-9–10-18l)amount of liquid can be manipulated by such a precise *** the past three decades,significant progress in materials science,microfabrication,and various applications has boosted the development of promising functional microfluidic *** this review,the recent progress on novel microfluidic devices with various functions and applications is ***,the theory and numerical methods for studying the performance of microfluidic devices are briefly ***,materials and fabrication methods of functional microfluidic devices are ***,the recent significant advances in applications of microfluidic devices are highlighted,including heat sinks,clean water production,chemical reactions,sensors,biomedicine,capillaric circuits,wearable electronic devices,and ***,perspectives on the challenges and future developments of functional microfluidic devices are *** review aims to inspire researchers from various fields engineering,materials,chemistry,mathematics,physics,and more—to collaborate and drive forward the development and applications of functional microfluidic devices,specifically for achieving carbon neutrality.

关键词： capillary theory functional devices functional microfluidics

Study on concentration distribution and detonation characteristics for non-axisymmetric fuel dispersal

在线全文

学校读者我要写书评

暂无评论

Defence Technology（防务技术） 2024年第1期31卷 484-495页

作者： Linghui Zeng Zhongqi wang xing Chen Jianping Li State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing100081China College of Environment and Chemical Engineering Sichuan University of Science&EngineeringZigong643000China

The study of non-axisymmetric fuel dispersal and detonation can provide reference for the prevention of industrial cloud explosion accidents and the design of fuel air explosive(FAE).The concentration and detonation fields of 85 kg cylindrical and fan-shaped fuel are investigated by experiments and numerical simulations.A dynamic model of the whole process for fuel dispersal and detonation is *** concentration distribution of fuel is used as the initial condition to calculate the detonation stage,thus solving the initial value problem of detonation *** phase and component changes of fuel cloud at different locations are *** fuel cloud is divided into directions of 0°,90°,135°and 180°.The results show that the maximum cloud radius is 20.94 m in 135°and the minimum is 12.04 m in 0°.The diameter of the detonation fireball is 53.6 m,and the peak temperature is 3455 *** highest peak overpressure is 3.44 MPa in 0°and the lowest is 2.97 MPa in 135°.The proportion of liquid phase in 0°is22.90%,and the fuel loss is 11.8% and 9% higher than that in 135°and cylindrical charge,*** stable propagation distance of blast wave in 135°is 42.50% longer than 0°and 28.37% longer than cylindrical charge.

关键词： Fuel dispersal Concentration distribution Detonation characteristic Fuel loss Numerical simulation

A brief review on the recent development of phonon engineering and manipulation at nanoscales

在线全文

学校读者我要写书评

暂无评论

International Journal of Extreme Manufacturing 2024年第1期6卷 177-206页

作者： Siqi Xie Hongxin Zhu xing Zhang Haidong wang Key Laboratory for Thermal Science and Power Engineering of Ministry of Education Department of Engineering MechanicsTsinghua UniversityBeijing 100084People’s Republic of China

Phonons are the quantum mechanical descriptions of vibrational modes that manifest themselves in many physical properties of condensed matter systems. As the size of electronic devices continues to decrease below mean free paths of acoustic phonons, the engineering of phonon spectra at the nanoscale becomes an important topic. Phonon manipulation allows for active control and management of heat fow, enabling functions such as regulated heat transport. At the same time, phonon transmission, as a novel signal transmission method, holds great potential to revolutionize modern industry like microelectronics technology, and boasts wide-ranging applications. Unlike fermions such as electrons, polarity regulation is difficult to act on phonons as bosons, making the development of effective phonon modulation methods a daunting *** work reviews the development of phonon engineering and strategies of phonon manipulation at different scales, reports the latest research progress of nanophononic devices such as thermal rectifiers, thermal transistors, thermal memories, and thermoelectric devices,and analyzes the phonon transport mechanisms involved. Lastly, we survey feasible perspectives and research directions of phonon engineering. Thermoelectric analogies, external field regulation, and acousto-optic co-optimization are expected to become future research hotspots.

关键词： phonon engineering phononic device nanoscale