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Quantum algorithms for matrix operations and linear systems of equations

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Communications in Theoretical Physics 2024年第3期76卷 100-112页

作者： Wentao Qi Alexandr I Zenchuk Asutosh Kumar Junde Wu School of Mathematical Sciences Zhejiang UniversityHangzhou 310027China Federal Research Center of Problems of Chemical Physics and Medicinal chemistry RAS ChernogolovkaRussia P.G.department of Physics Gaya CollegeMagadh UniversityRampurGaya 823001India Harish-Chandra Research Institute HBNIChhatnag RoadJhunsiPrayagraj 211019India Vaidic and Modern Physics Research centre Bhagal BhimBhinmalJalore 343029India

Fundamental matrix operations and solving linear systems of equations are ubiquitous in scientific investigations.Using the‘sender-receiver’model,we propose quantum algorithms for matrix operations such as matrix-vector product,matrix-matrix product,the sum of two matrices,and the calculation of determinant and inverse matrix.We encode the matrix entries into the probability amplitudes of the pure initial states of senders.After applying proper unitary transformation to the complete quantum system,the desired result can be found in certain blocks of the receiver’s density matrix.These quantum protocols can be used as subroutines in other quantum schemes.Furthermore,we present an alternative quantum algorithm for solving linear systems of equations.

关键词： matrix operation systems of linear equations ‘sender-receiver’quantum computation model quantum algorithm

Reductive Coupling of Aryl Halides via C-H Activation of Indene

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Chinese Journal of chemistry 2021年第6期39卷 1573-1579页

作者： Bo-Sheng Zhang Ying-Hui Yang Fan Wang Xue-Ya Gou Xi-Cun Wang Yong-Min Liang Yuke Li Zheng-Jun Quan College of chemistry and Chemical Engineering Gonsu International Scientific and Technological Cooperation Base of Water-Retention Chemical Functional MaterialsNorthwest Normal UniversityLanzhouGansu 730070China State Key Laboratory of Applied Organic chemistry Lanzhou UniversityLanzhouGansu 730000China department of chemistry and centre for scientific modeling and computation Chinese University of Hong KongShatinHong KongChina

This paper describes the first case of a reductive coupling reaction with indene,a non-heteroatom olefin used as a reducing agent.The scope of the substrate is wide.The homo-coupling,cross-coupling,and synthesis of 12 and 14-membered rings were realized.The control experiment,indene-product curve and density functional theory calculations showed that the η^(3)-palladium indene intermediate was formed by C-H activation in the presence of cesium carbonate.We speculate that the final product was obtained through a Pd(IV)intermediate or aryl ligand exchange.In addition,we excluded the formation of palladium anion(Pd(0)^(-))intermediates.

关键词： C-C coupling Palladium Reduction Indene C-H activation

Constraint Preserving Schemes Using Potential-Based Fluxes I.Multidimensional Transport Equations

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Communications in computational Physics 2011年第3期9卷 688-710页

作者： Siddhartha Mishra Eitan Tadmor centre of Mathematics for Applications(CMA) University of OsloP.O.Box 1053BlindernN-0316 OsloNorway Center of scientific computation and Mathematical modeling(CSCAMM) and Department of Mathematicsand Institute for Physical Sciences and Technology(IPST)University of MarylandMD 20742-4015USA

We consider constraint preserving multidimensional evolution equations.A prototypical example is provided by the magnetic induction equation of plasma physics.The constraint of interest is the divergence of the magnetic field.We design finite volume schemes which approximate these equations in a stable manner and preserve a discrete version of the constraint.The schemes are based on reformulating standard edge centered finite volume fluxes in terms of vertex centered potentials.The potential-based approach provides a general framework for faithful discretizations of constraint transport and we apply it to both divergence preserving as well as curl preserving equations.We present benchmark numerical tests which confirm that our potential-based schemes achieve high resolution,while being constraint preserving.

关键词： Multidimensional evolution equations magnetohydrodynamics finite-difference finite volume schemes constraint transport potential-based schemes

Linear scaling Coulomb interaction in the multiwavelet basis,a parallel implementation

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International Journal of modeling, Simulation, and scientific Computing 2014年第S1期5卷 28-50页

作者： Stig Rune Jensen Jonas Jusélius Antoine Durdek Tor Fl˚a Peter Wind Luca Frediani department of Physics and Technology centre for Theoretical and computational chemistry UiT The Arctic University of Norway N-9037 TromsøNorway High Performance Computing Group centre for Theoretical and computational chemistry UiT The Arctic University of Norway N-9037 TromsøNorway department of Mathematics and Statistics centre for Theoretical and computational chemistry UiT The Arctic University of Norway N-9037 TromsøNorway department of chemistry centre for Theoretical and computational chemistry UiT The Arctic University of Norway N-9037 TromsøNorway

We present a parallel and linear scaling implementation of the calculation of the electrostatic potential arising from an arbitrary charge distribution.Our approach is making use of the multi-resolution basis of multiwavelets.The potential is obtained as the direct solution of the Poisson equation in its Green’s function integral form.In the multiwavelet basis,the formally non local integral operator decays rapidly to negligible values away from the main diagonal,yielding an effectively banded structure where the bandwidth is only dictated by the requested accuracy.This sparse operator structure has been exploited to achieve linear scaling and parallel algorithms.Parallelization has been achieved both through the shared memory(OpenMP)and the message passing interface(MPI)paradigm.Our implementation has been tested by computing the electrostatic potential of the electronic density of long-chain alkanes and diamond fragments showing(sub)linear scaling with the system size and efficent parallelization.

关键词： Multiwavelets electrostatic potentials Poisson equation integral operators linear scaling parallel implementation

Sb_(2)Te_(3)/graphite nanocomposite: A comprehensive study of thermal conductivity

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Journal of Materiomics 2021年第3期7卷 545-555页

作者： Subarna Das P.Singha V.A.Kulbachinskii V.G.Kytin Gangadhar Das S.Janaky A.K.Deb Sudip Mukherjee A.Maignan S.Hebert R.Daou Chandrabhas Narayana S.Bandyopadhyay Aritra Banerjee department of Physics University of Calcutta92 A P C RoadKolkata700009India Laboratoire de Cristallographie et Sciences des Materiaux(CRISMAT) Normandie UniversiteUMR6508 CNRSENSICAENUNICAEN14000CaenFrance department of Low Temperature Physics and Superconductivity Physics FacultyM.V.Lomonosov Moscow State University119991MoscowRussia Moscow Institute of Physics and Technology 141700DolgoprudnyMoscow RegionRussia chemistry and Physics of Materials Unit Jawaharlal Nehru Centre for Advanced Scientific ResearchJakkur P.OBangalore560064India department of Physics Raiganj UniversityUttar DinajpurWest Bengal733134India UGC-DAE Consortium for scientific Research Mumbai CentreR-5 ShedBARC CampusTrombayMumbai400008India Center for Research in Nanoscience and Nanotechnology University of CalcuttaJD-2Sector-IIISaltlakeKolkata700106India

Thermoelectric performance largely depends on the reduction of lattice thermal conductivity(kL).The study of the thermal conductivity(k)of a Sb_(2)Te_(3)/graphite nanocomposite system demonstrates-40%reduction in kL with graphite incorporation.A plausible explanation of intrinsic low kL observed in Sb_(2)Te_(3) based system is presented by modeling experimental specific heat(Cp)data.Raman spectroscopy measurement combined to X-Ray diffraction data confirms the presence of graphite as separate phase in the composite sample.It is found that phonon scattering dominates heat transport mechanism in the nanostructured Sb_(2)Te_(3)/graphite composite.Large reduction in kL is accomplished by intensifying scattering rate of phonons via various sources.Graphite introduces effective scattering sources,i.e.,defects of different dimensionalities in synthesized nanocomposite sample.Furthermore,graphite mediates phonon-phonon coupling and enhances lattice anharmonicity,which causes an intrinsic scattering of phonons with all frequencies in the Sb_(2)Te_(3)/graphite nanocomposite sample.Dislocation density and phonon anharmonicity of the synthesized samples are estimated from in depth analysis of temperature dependent synchrotron powder diffraction and Raman spectroscopic data.kL value as low as 0.8 W m1 K1 at 300 K,achieved with graphite dispersion in Sb_(2)Te_(3) based composite system makes the present comprehensive study an interesting concept to be developed in thermoelectric materials.

关键词： Thermoelectric systems Thermal conductivity Phonons X-ray powder diffraction Raman spectroscopy Specific heat measurements

High-throughput calculations of charged point defect properties with semi-local density functional theory— performance benchmarks for materials screening applications

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npj computational Materials 2023年第1期9卷 1628-1639页

作者： Danny Broberg Kyle Bystrom Shivani Srivastava Diana Dahliah Benjamin A.D.Williamson Leigh Weston David O.Scanlon Gian-Marco Rignanese Shyam Dwaraknath Joel Varley Kristin A.Persson Mark Asta Geoffroy Hautier Materials Sciences Division Lawrence Berkeley National Laboratory1 Cyclotron RoadBerkeleyCA 94720USA department of Materials Science and Engineering University of CaliforniaBerkeleyCA 94720USA John A.Paulson School of Engineering and Applied Sciences Harvard UniversityCambridgeMA 02138USA department of Physics An-Najah National UniversityNablusPalestine Institute of Condensed Matter and Nanosciences UniversitéCatholique de LouvainChemin desÉtoiles 8B-1348 Louvain-la-NeuveBelgium department of Materials Science and Engineering NTNU Norwegian University of Science and TechnologyTrondheimNorway Energy Technologies Area Lawrence Berkeley National Laboratory1 Cyclotron RoadBerkeleyCA 94720USA department of chemistry University College London20 Gordon StreetLondon WC1H 0AJUK Thomas Young centre University College LondonGower StreetLondon WC1E 6BTUK Diamond Light Source Ltd. Diamond HouseHarwell Science and Innovation CampusDidcotOxfordshire OX110DEUK Lawrence Livermore National Laboratory LivermoreCA 94550USA Molecular Foundry Lawrence Berkeley National Laboratory1 Cyclotron RoadBerkeleyCA 94720USA Thayer School of Engineering Dartmouth CollegeHanoverNH 03755USA

Calculations of point defect energetics with Density Functional Theory(DFT)can provide valuable insight into several optoelectronic,thermodynamic,and kinetic properties.These calculations commonly use methods ranging from semi-local functionals with a-posteriori corrections to more computationally intensive hybrid functional approaches.For applications of DFT-based high-throughput computation for data-driven materials discovery,point defect properties are of interest,yet are currently excluded from available materials databases.This work presents a benchmark analysis of automated,semi-local point defect calculations with a-posteriori corrections,compared to 245“gold standard”hybrid calculations previously published.We consider three different a-posteriori correction sets implemented in an automated workflow,and evaluate the qualitative and quantitative differences among four different categories of defect information:thermodynamic transition levels,formation energies,Fermi levels,and dopability limits.We highlight qualitative information that can be extracted from high-throughput calculations based on semi-local DFT methods,while also demonstrating the limits of quantitative accuracy.

关键词： properties defect correction

A new era of China-Germany joint research exploring the climate mystery of Earth

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Science Bulletin 2019年第23期64卷 1733-1736页

作者： Tianjun Zhou Jung Luterbacher Shaohong Wu Chao Li Qingchen Chao Xiao Cheng Yihong Duan Jian Li Bjorn Stevens Sebastian Voigt Yuanhang Zhang Xunhua Zheng Liwei Zou State Key Laboratory of Numerical modeling for Atmospheric Sciences and Geophysical Fluid Dynamics(LASG) Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China Center for Excellence in Tibetan Plateau Earth Sciences Chinese Academy of SciencesBeijing 100101China department of Geography ClimatologyClimate Dynamics and Climate ChangeJustus-Liebig University of GiessenGiessen 35390Germany centre for International Development and Environmental Research University of GiessenGiessen 35390Germany Institute of Geographic Sciences and Natural Resources Research Chinese Academy of SciencesBeijing 100101China Max Planck Institute for Meteorology Hamburg 20146Germany Beijing Climate Center China Meteorology AdministrationBeijing 100081China College of Global Change and Earth System Science Beijing Normal UniversityBeijing 100875China Chinese Academy of Meteorological Sciences China Meteorological AdministrationBeijing 100081China centre for European Economic Research Mannheim 68161Germany College of Environmental Sciences and Engineering Peking UniversityBeijing 100871China State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric chemistry(LAPC) Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China

China and Germany have a long history of collaborating in the Earth sciences. One example is the collaborative work in plumbing the mysteries of climate in China. German geographer Prof. Dr. Ferdinand von Richthofen led the first scientific expedition of the Loess Plateau and Lop Nur during the 1870s. The expedition established the theory of the eolian origin of the plateau. The term"Silk Road"("die Seidenstrasse" in German) was also coined by Prof.

关键词： China. Earth climate

Impact of Bionanocomposite on Some Immunological and Biochemical Parameters at Gastric Mucosa Ulceration Simulation

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材料科学与工程（中英文A版） 2014年第9期4卷 303-308页

作者： Yakubtsova Iryna Volodymyrivna Khilko Tetyana Dmytrivna Voronin Evgeniy Pylypovych Preobrazhenska Tamara Dmytrivna Ostapchenko Lyudmyla Ivanivna Makai Sandor Educational and scientific centre "Institute of Biology " Taras Shevehenko Kyiv National University Kyiv 01601 Ukraine Institute of Surface chemistry O. O. Chuiko NAS of Ukraine NAS of Ukraine Kyiv 03164 Ukraine Institut of Crop Sciences Faculty of Agricultural and Food Sciences Department of Medicinal and Aromatic Plants University ofthe West Hungary Mosonmagyarovar H-9200 Hungary

It was held a comparative assessment of immunological and biochemical parameters of blood in the normal, at the modeling stress ulcer in rats and at the introduction of bionanocomposite to experimental animals. It was shown that under conditions of stress ulcer model the level of TNF-α increased 1.7 times, the level of IL-4 compared with controls was reduced to 1.9 times. It was observed decrease of lysozyme content in gastric mucosa by 1.7-fold compared with the control group animals. At the modeling stress gastric ulcer activities of AST, ALT, alkaline phosphatase in serum increased respectively to 1.9, 1.2 and 2.2 times. Introduction of biocomposite stress-affected rats showed the normalization of the investigated immunological and biochemical parameters of blood. The new bionanocomposite was created that combines healing properties of biologically active substances of seed Trigonella foenum graecum L. and nanosilix

关键词：生化指标胃溃疡免疫学胃黏膜生物活性物质血清碱性磷酸酶模拟应激性

Bionanocomposite Effect on Mucosal Protection Indicators at Mucosa Gastric Ulceration Simulation

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材料科学与工程（中英文A版） 2013年第9期3卷 635-639页

作者： Yakubtsova Irina Volodymynvna Khilko Tatiana Dmytrivna Voronin Evgeny Pylypovych PreobrazhenskaTamara Dmytrivna Ostapchenko Lyudmila Ivanivna Makai Sandor Educational and scientific centre "Institute of Biology" Taras Shevchenko Kyiv National University Kyiv 01601 Ukraine Institute of Surface chemistry 0.0. Chuiko NAS of Ukraine NAS of Ukraine Kyiv 03164 Ukraine Institut of Crop Sciences Faculty of Agricultural and Food Sciences Department of Medicinal and Aromatic Plants Universityof the West Hungary Mosonmagyar6v6r 11-9200 Ukraine

It was investigated the qualitative and quantitative composition of monosaccharides glycoprotein (GP) of gastric parietal layer of protective mucus in the normal, at the modeling stress ulcer in rats and at the introduction of bionanocomposite to experimental animals. In analyzing the content of glycoproteins monosaccharides of the protective mucus we found that under conditions of stress ulcer model in the mucus of the stomach, a decrease 2.2 times galactose, fucose 1.3 times, 1.8 times hexosamines. It was seen an increase in N-acetylneuraminic acid in 3.6 times, which may be indicated the depolymerization of glycoproteins. The new biocomposite was created to maximize the using of biologically active substances Trigonella foenum graecum seeds were transferred to highly dispersed state by immobilization on the surface nanosilex. of biocomposite stress-affected rats showed the normalization of the composition glycoproteins" monosaccharides of gastric parietal mucous layer.

关键词：胃溃疡保护性模拟粘液糖蛋白黏膜生物活性物质生物复合材料实验动物