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Shor's algorithm does not factor large integers in the presence of noise

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Science China(Information Sciences) 2024年第7期67卷 305-320页

作者： Jin-yi cai College of Letters and Science University of Wisconsin

We consider Shor's quantum factoring algorithm in the setting of noisy quantum gates. Under a generic model of random noise for(controlled) rotation gates, we prove that the algorithm does not factor integers of the form pq when the noise exceeds a vanishingly small level in terms of n—the number of bits of the integer to be factored, where p and q are from a well-defined set of primes of positive density. We further prove that with probability 1-o(1) over random prime pairs(p, q), Shor's factoring algorithm does not factor numbers of the form pq, with the same level of random noise present.

关键词： random noise Shor's algorithm rotation gates quantum computing prime factorization

Rapidly growing primordial black holes as seeds of the massive high-redshift JWST Galaxies

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Science China(Physics,Mechanics & Astronomy) 2024年第10期67卷 139-146页

作者： Guan-Wen Yuan Lei Lei Yuan-Zhu Wang Bo Wang yi-ying Wang chao Chen Zhao-Qiang Shen yi-Fu cai yi-Zhong Fan Key Laboratory of Dark Matter and Space Astronomy Purple Mountain ObservatoryChinese Academy of SciencesNanjing 210023China School of Astronomy and Space Science University of Science and Technology of ChinaHefei 230026China Institute of High Energy Physics Chinese Academy of SciencesBeijing 100049China Deep Space Exploration Laboratory/Department of Astronomy School of Physical SciencesUniversity of Science and Technology of ChinaHefei 230026China Jockey Club Institute for Advanced Study The Hong Kong University of Science and TechnologyHong KongChina

A group of massive galaxies at redshifts of z■7 have been recently detected by the James Webb Space Telescope(JWST),which were unexpected to form at such an early time within the standard Big Bang *** this work,we propose that this puzzle can be explained by the presence of some primordial black holes(PBHs)with a mass of~1000M_(⊙).These PBHs act as seeds for early galaxy formation with masses of~10^(8)-10^(10)M_(⊙)at high redshift,hence accounting for the JWST *** use a hierarchical Bayesian inference framework to constrain the PBH mass distribution models,and find that the Lognormal model with the M_(c)~750M_(⊙)is preferred over other *** rapidly growing BHs are expected to have strong radiation and may appear as high-redshift compact objects,similar to those recently discovered by *** we focused on PBHs in this work,the bound on the initial mass of the seed black holes remains robust even if they were formed through astrophysical channels.

关键词： primordial black hole dark matter halo black hole accretion primordial galaxies

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Petroleum Science 2024年第4期21卷 2383-2392页

作者： Li-Ming Zhao cai-Ping Lu Yang Liu chao-chao Li School of Mines China University of Mining and Technology Henan Institute of Geophysical Space Information

The similarities and differences in inherent mechanism and characteristic frequency between the onedimensional(1D) poroelastic model and the layered White model were investigated. This investigation was conducted under the assumption that the rock was homogenous and isotropic at the mesoscopic scale. For the inherent mechanism, both models resulted from quasi-static flow in a slow P-wave diffusion mode, and the differences between them originated from saturated fluids and boundary conditions. On the other hand, for the characteristic frequencies of the models, the characteristic frequency of the 1D poroelastic model was first modified because the elastic constant and formula for calculating it were misused and then compared to that of the layered White model. Both of them moved towards higher frequencies with increasing permeability and decreasing viscosity and diffusion length. The differences between them were due to the diffusion length. The diffusion length for the 1D poroelastic model was determined by the sample length, whereas that for the layered White model was determined by the length of the representative elementary volume(REV). Subsequently, a numerical example was presented to demonstrate the similarities and differences between the models. Finally, published experimental data were interpreted using the 1D poroelastic model combined with the Cole-Cole *** prediction of the combined model was in good agreement with the experimental data, thereby validating the effectiveness of the 1D poroelastic model. Furthermore, the modified characteristic frequency in our study was much closer to the experimental data than the previous prediction, validating the effectiveness of our modification of the characteristic frequency of the 1D poroelastic model. The investigation provided insight into the internal relationship between wave-induced fluid flow(WIFF)models at macroscopic and mesoscopic scales and can aid in a better understanding of the elastic modulus d

关键词： 1D poroelastic model Layered White model Quasi-static flow Slow P-wave diffusion Characteristic frequency Diffusion length

Mechanics and physics under supergravity conditions

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Acta Mechanica Sinica 2024年第6期40卷 1-2页

作者： chaofeng Lü chao Sun Shengqiang cai Faculty of Mechanical Engineering and Mechanics Ningbo UniversityNingbo 315211China New Cornerstone Science Laboratory Center for Combustion EnergyDepartment of Energy and Power EngineeringTsinghua UniversityBeijing 100084China Department of Mechanical and Aerospace Engineering University of CaliforniaSan DiegoLa Jolla CA 92093USA

"Supergravity"refers to the conditions where the effective gravity is greater than that of *** conditions are generally relevant to stellar evolution,geophysical movement,astrophysical flows,and *** also frequently occur in various engineering scenarios involving acceleration,such as the launch of space shuttles,operation of rotor engines,impacts and explosions,chemical separation processes,and overloaded testing *** is already demonstrated in physiological experiments that living organisms of animals or plants could be damaged,either temporarily or permanently,when subjected to *** create supergravity conditions for scientific research on the Earth,centrifugal equipment or rapidly rotating devices are omnipresent in various fields,such as aerospace engineering,geophysical science,chemical and biomedical engineering,nuclear engineering,rotating flows,and physical modeling tests.

关键词： geophysical Earth stellar

Interplay between Microscopic Structures and Macroscopic Viscoelastic Properties of Polyampholyte Gels

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Chinese Journal of Polymer Science 2024年第9期42卷 1360-1367,I0008页

作者： You-cai Xue yi-Ming Yang Di Jia Beijing National Laboratory for Molecular Sciences Laboratory of Polymer Physics and ChemistryInstitute of ChemistryChinese Academy of SciencesBeijing100190China University of Chinese Academy of Sciences Beijing100049China

Polyampholyte gels,which have hierarchical structures,exhibit excellent self-healing properties and have great promise for biomaterials and *** investigated the relationship between microscopic structures and macroscopic viscoelastic properties of polyampholyte gels and found three factors influencing their viscoelastic properties,including the chemical crosslinking bonds,topological entanglements controlled by monomer concentration,and the ionic *** strength plays a major role on the strength of ionic bonds.A crossover point of elastic modulus and loss modulus was observed in the dynamic frequency sweeps at low monomer concentration or low chemical crosslinking density for gels with intermediate strength of ionic *** solid-liquid transition signaled by the crossover point is a typical feature of dynamic associated gels,representing the dynamical association-dissociation of the ionic bonds and full relaxation of the topological entanglements in the gel *** the crossover point disappears when the ionic bonds are too weak or too strong to form“permanent”***,in the non-linear yielding measurement,gels with intermediate strength of the ionic bonds are ductile and yield at very large shear strain due to the self-healing properties and the dynamic association-dissociation of the ionic *** the self-healing properties disappear when the ionic bond strength is too weak or too *** work reveals the mechanism of how the dynamic association-dissociation of ionic bonds influences both the linear and non-linear viscoelastic properties of the polyampholyte gels.

关键词： Polyampholyte gel Ionic bond Topological entanglement Self-healing Hierarchical structure

N-Heterocyclic carbene-catalyzed enantioselective(dynamic) kinetic resolutions and desymmetrizations

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Science China Chemistry 2024年第2期67卷 482-511页

作者： yi Zhang Hui cai Xiuhai Gan Zhichao Jin National Key Laboratory of Green Pesticide Key Laboratory of Green Pesticide and Agricultural BioengineeringMinistry of EducationGuizhou UniversityHuaxi DistrictGuiyang550025China

N-heterocyclic carbene-catalyzed enantioselective kinetic resolutions,dynamic kinetic resolutions,and desymmetrization reactions are systematically *** content is organized according to the activation modes involved i... 详细信息

关键词： N-heterocyclic carbene kinetic resolution dynamic kinetic resolution desymmetrization organocatalysis

Hydrogen bond-induced elastic polyzwitterion electrolytes constructed by mussel-inspired autopolymerization for zinc-ion battery

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Science China Chemistry 2024年第10期67卷 3438-3449页

作者： Shi Wang Xinyi Wu chao Liu Lingjun He Shuanghan Li Yuqi Miao Mingrui cai yi Li Zheng-Dong Huang Wen-Yong Lai State Key Laboratory of Organic Electronics and Information Displays(SKLOEID) Institute of Advanced Materials(IAM)School of Chemistry and Life SciencesNanjing University of Posts&TelecommunicationsNanjing 210023China

Aqueous zinc-ion batteries(ZIBs)have attracted much interest to realize safe rechargeable batteries with high safety and high energy ***,it is still challenging to address dendrite growth and parasitic reactions in zinc *** propose herein the design concept of hydrogen bond-induced elastic polyzwitterion electrolytes with zincophilic groups for achieving robust ***-inspired autopolymerization has been developed to construct the polyzwitterion electrolytes at room temperature by inducing electron density delocalization atα-position of C=C bond in zwitterion monomer by Zn^(2+).Specifically,the zwitterionic functional groups construct ion transport channels,and the unique–NH–and SO_(3)^(-)groups co-compete with H_(2)O for coordination with Zn^(2+)and promote the desolvation of hydrated Zn^(2+),thus achieving a high room temperature ionic conductivity(6.7 mS cm^(-1))and an increased Zn^(2+)migration number(0.65)for the polyzwitterion *** addition,various interactions such as hydrogen bonding and electrostatic interactions between electrolyte ions and zwitterionic groups impart high stretchability and strength to the polyzwitterion electrolytes,which,combined with SO_(3)^(-)philic(002)crystallographic properties,effectively inhibit the growth of zinc *** a result,rigid/wearable solid-state ZIBs exhibit excellent cycling and C-rate *** believe that the strategy of constructing polyzwitterionic electrolytes with zincophilic groups and ion transport channels opens up a new direction in polymer electrolyte engineering towards safe and high energy batteries.

关键词： flexible electronics wearable electronics polyzwitterion electrolytes self-polymerization zinc-ion batteries

Sedimentary Environment and Mineralization of the Black Shale Polymetallic Layer in the Early Cambrian,SW China:Constraints from in situ LA-ICP-MS Analysis of Pyrite

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Acta Geologica Sinica(English Edition) 2024年第2期98卷 416-429页

作者： YANG Zhen FU Yong LI chao cai Xi GUO Chuan College of Eco-Environmental Engineering Guizhou Minzu UniversityGuiyang 550025China College of Resources and Environmental Engineering Guizhou UniversityGuiyang 550025China Key Laboratory of Karst Georesources and the Environment Ministry of EducationGuizhou UniversityGuiyang 500025China National Research Center for Geoanalysis Chinese Academy of Geological SciencesBeijing 100037China

A polymetallic layer is usually developed at the bottom of the early Cambrian black shale in Guizhou *** mineral that makes up the polymetallic layer is related to the sedimentary *** analyze the differentiation mechanism between polymetallic deposits(Ni-Mo and V),the Zhijin Gezhongwu profile located in the outer shelf and the Sansui Haishan V deposit located in the lower slope are selected to study the in situ sulfur isotopes and trace elements of *** results show that δ^(34)S values of pyrite vary widely from−7.8‰to 28‰in the Gezhongwu profile,while the δ^(34)S values are relatively uniform(from 27.8‰to 38.4‰)in the Haishan *** isotopic S composition is consistent with the transition that occurs in the sedimentary phase from the shelf to the deep sea on the transgressive Yangtze platform;this indicates that the δ^(34)SO_(4)^(2−)values in seawater must be differently distributed in depositional *** sulfur in the Ni-Mo layer is produced after the mixing of seawater and hydrothermal fluid,while the V layer mainly originates from ***,the Ni-Mo and V deposits have been differentiated primarily on the basis of the combined effect of continental weathering and hydrothermal fluid.

关键词： sedimentary environment black shale polymetallic layer pyrite early Cambrian

Pore-scale water-gas distribution and gas permeability of natural gas hydrate reservoirs in the South China Sea

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Geoscience Frontiers 2024年第4期15卷 315-329页

作者： Yuxuan Xia Derek Elsworth Jianchao cai Cheng Lu chao Ma National Key Laboratory of Petroleum Resources and Engineering China University of PetroleumBeijing 102249China Department of Energy and Mineral Engineering G3 Center and Energy InstituteThe Pennsylvania State UniversityUniversity Park 16802PAUnited States Guangzhou Marine Geological Survey China Geological SurveyGuangzhou 510075China Center of Oil&Natural Gas Resource Exploration China Geological SurveyBeijing 100083China

Challenges in water drainage within natural gas hydrate reservoirs in the Shenhu area of the South China Sea,characterized by high clay content and strong hydrophilicity,significantly hinder natural gas *** the effects of gas pressure and liquid/gas saturation on gas permeability reveals essential insights for increasing gas production *** report gas displacement experiments on clayey-silt sediment samples,alongside X-ray computed tomography imaging,that reveal critical findings:a notable increase in flow rate and permeability as displacement pressure nears compaction pressure,highlighting the role of pressure management in enhancing recovery;water displacement from varying pore sizes under different pressures,highlighting the influence of pore size on fluid dynamics,and structural changes,including microfracture formation and a significant fracture that enlarges total pore space by about 15%,which collectively suggest methods to improve gas flow and ***,our analysis identifies average throat length,fractal dimension,and succolarity as principal controls on gas permeability,indicating the substantial impact of microstructural properties on extraction *** outcomes offer valuable strategies for optimizing natural gas hydrate reservoir development in the South China Sea,emphasizing the need for meticulous pressure and saturation control and in applying a deep understanding of microstructural dynamics.

关键词： Natural gas hydrate Clayey-silt sediments Gas saturation Gas permeability Microstructure