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应用数学与计算数学学报 2017年第2期31卷 143-152页

作者： belov a v LOS A B ROZHKOv M I 高等经济大学俄罗斯莫斯科101000

研究在有限域上构造MDS方阵的一些方法,这类矩阵作为扩散映射用于构建块加密算法和检验函数.给出了若干类4阶循环MDS矩阵以及具有最多单位元的4阶MDS矩阵.

关键词： MDS矩阵 MDS编码数据保护算法

Development of Mg-Zn-Y-Zr casting magnesium alloy with high thermal conductivity

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Journal of Magnesium and Alloys 2021年第5期9卷 1583-1593页

作者： v.E.Bazhenov A.v.Koltygin M.C.Sung S.H.Park Yu.v.Tselovalnik A.A.Stepashkin A.A.Rizhsky M.v.belov v.D.belov K.v.Malyutin National University of Science and Technology“MISiS” Leninskiy pr.4Moscow 119049 Russia LG Electronics Inc. Yeoui-daeroYeongdeungpo-gu.128LG Twin TowerSeoul 07336 Republic of Korea

Magnesium alloys are used in aircraft because of their light weight.However,for these alloys to be applied in electronic devices,high thermal conductivities are required.Several high-potential compositions of Mg-Zn-Y-Zr alloys were selected by phase composition and their freezing ranges calculated using Thermo-Calc software.The alloys were prepared,and their fluidity,hot tearing susceptibility,mechanical properties,and thermal conductivity were obtained and compared.The alloy composed of Mg-4 wt%Zn-3 wt%Y-0.3 wt%Zr was selected for further investigation,because of its high thermal conductivity and satisfactory mechanical properties.The Mg-4 wt%Zn-3 wt%Y-0.3 wt%Zr alloy’s fluidity and hot tearing susceptibility were similar to those of the widespread AZ91 commercial casting magnesium alloy.The influence of a heat treatment regime on the microstructure,thermal conductivity,and mechanical properties of the developed alloy was also investigated.It was established that the room temperature thermal conductivity of the Mg-4 wt%Zn-3 wt%Y-0.3 wt%Zr alloy after aging at 300℃for 5 h was 105 W/m K^(-1).Additionally,the following tensile test results were obtained in aged condition:120 MPa yield strength,200 MPa ultimate tensile strength,and 4%elongation.The utilization of solid solution heat treatment at 520℃for 8 h prior to aging can promote up to 9%increase in elongation.The Mg-4 wt%Zn-3 wt%Y-0.3 wt%Zr casting alloy can be used as a high thermal conductivity material with industrial applications.

关键词： Magnesium alloy Mg-Zn-Y-Zr Thermal conductivity Phase composition Fluidity Hot tearing susceptibility

Design of Mg-Zn-Si-Ca casting magnesium alloy with high thermal conductivity

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Journal of Magnesium and Alloys 2020年第1期8卷 184-191页

作者： v.E.Bazhenov A.v.Koltygin M.C.Sung S.H.Park A.Yu.Titov v.A.Bautin S.v.Matveev M.v.belov v.D.belov K.v.Malyutin National University of Science and Technology“MISiS” Leninskiy pr.4Moscow 119049Russia LG Electronics Inc. Yeoui-daeroYeongdeungpo-gu.128LG Twin TowerSeoul 07336 Republic of Korea

Magnesium alloys are commonly used to produce lightweight parts.While most magnesium alloys exhibit low thermal conductivities,high thermal conductivities are needed for electronic devices.In this study,we attempted to develop new magnesium casting alloys with high thermal conductivities.The Mg-Zn-Si-Ca alloy compositions were chosen using CALPHAD(CALculation of PHAse Diagrams)calculations,and alloy samples were prepared.The fluidity and hot-tearing resistance were measured.The results indicated that these properties were similar to those of AZ91 alloy.Tensile tests showed that high-pressure die casting could produce Mg-Zn-Si-Ca alloys possessing mechanical properties 1.5-3 times higher than those produced via sand casting.The alloy thermal conductivity was 126 W/mK at room temperature.The corrosion rates of the as-cast samples in NaCl/water solutions were two times higher than that of AZ91.

关键词： Magnesium alloy Thermal conductivity Phase composition Corrosion rate Sand casting High-pressure die casting

Al-Ca-Cu三元合金体系中与铝平衡的金属间化合物

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Transactions of Nonferrous Metals Society of China 2024年第5期34卷 1380-1392页

作者： T.K.AKOPYAN T.A.SvIRIDOvA N.A.belov N.v.LETYAGIN A.v.KOROTITSKIY National University of Science and Technology MISiS 4 Leninsky pr.Moscow 119049Russia

对三元Al-Ca-Cu合金体系中与铝固溶体平衡的(Al,Cu)_(4)Ca、Al_(27)Ca_(3)Cu_(7)和Al_(8)CaCu_(4)金属间化合物的结构和性能进行全面分析。基于Al4Ca相中部分Al原子被Cu取代,将(Al,Cu)_(4)Ca金属间化合物视为线性化合物。化合物中铜的... 详细信息

对三元Al-Ca-Cu合金体系中与铝固溶体平衡的(Al,Cu)_(4)Ca、Al_(27)Ca_(3)Cu_(7)和Al_(8)CaCu_(4)金属间化合物的结构和性能进行全面分析。基于Al4Ca相中部分Al原子被Cu取代,将(Al,Cu)_(4)Ca金属间化合物视为线性化合物。化合物中铜的溶解度达到10 at.%(19 wt.%),导致化合物的晶格结构、物理和力学性能发生显著变化。例如,化合物的密度从2.22 g/cm^(3)增加到2.79 g/cm^(3),显微硬度从Hv 180增加到Hv 250。将Al_(27)Ca_(3)Cu_(7)相视为具有严格化学计量比和BaHg11型初始晶体结构的三元化合物,其空间群为Pm3m,晶格参数为8.514Å,密度为3.45 g/cm^(3)。Al_(8)CaCu_(4)相也是严格化学计量比的三元化合物,具有Mn_(12)Th型晶格结构,最高的显微硬度(Hv 505)和密度(4.57 g/cm^(3))。属于二元(Al)+(Al,Cu)_(4)Ca相场和准二元(Al)+Al_(27)Ca_(3)Cu_(7)截面的合金,有前景作为新型天然铝基复合材料的基材。

关键词：金属间化合物 Al-Ca合金显微组织晶体结构物理性能力学性能

Antibacterial HA-coatings on bioresorbable Mg alloy

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Journal of Magnesium and Alloys 2024年第5期12卷 1965-1985页

作者： K.v.Nadaraia D.v.Mashtalyar M.A.Piatkova A.I.Pleshkova I.M.Imshinetskiy M.S.Gerasimenko E.A.belov v.v.Kumeiko D.N.Kozyrev K.A.Fomenko v.v.Mostovaya B.R.Torpanov A.R.Biktimirov I.S.Osmushko S.L.Sinebryukhov S.v.Gnedenkov Institute of Chemistry FEB RAS Far Eastern Federal University A.v.Zhirmunsky National Scientific Center of Marine Biology FEB RAS Regional Clinical Dermatovenerological Dispensary NMIC “Treatment and Rehabilitation Center”

In this study, a calcium-phosphate coating was formed on a Mg-Mn-Ce alloy by the plasma electrolytic oxidation(PEO). The antibiotic vancomycin, widely used in the treatment of infections caused by Staphylococcus aureus(S. aureus), was impregnated into the coating.Samples with vancomycin showed high bactericidal activity against S. aureus. The mechanical and electrochemical properties of the formed coatings were studied, as well as in vitro cytotoxicity tests and in vivo tests on mature male rats were performed. According to SEM,EDS, XRD and XPS data, coatings had a developed morphology and contained hydroxyapatite, which indicates high biocompatibility.The analysis of roughness of coatings without and with vancomycin did not reveal any differences, confirming the high roughness of the samples. During electrochemical tests, an increase in corrosion resistance by more than two times after the application of PEO coatings was revealed. According to the results of an in vivo study, after 28 days of the implantation of samples with calcium phosphate PEO coating and vancomycin, no signs of inflammation were observed, while an inflammatory reaction developed in the area of implantation of bare alloy,followed by encapsulation. Antibiotic release tests from the coatings show a sharp decrease in the concentration of the released antibiotic on day 7 and then a gradual decrease until day 28. Throughout the experiment, no significant deviations in the condition and behavior of the animals were observed; clinical tests did not reveal a systemic toxic reaction.

关键词： Bioactive coatings Biocompatibility Mg alloy Plasma electrolytic oxidation Hydroxyapatite vancomycin

Al-Ca-Fe合金中Al_(10)CaFe_(2)化合物的形成与表征

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Transactions of Nonferrous Metals Society of China 2024年第2期34卷 361-377页

作者： N.A.belov T.K.AKOPYAN E.A.NAUMOvA v.v.DOROSHENKO T.A.SvIRIDOvA N.O.KOROTKOvA National University of Science and Technology MISIS 4 Leninsky pr.Moscow 119049Russia Baikov Institute of Metallurgy and Materials Science 49 Leninsky pr.Moscow 119991Russia

采用热力学计算和实验技术研究铝角的Al-Ca-Fe体系相图,包括液相面投影图和凝固反应。结果表明,与铝固溶体(Al)平衡的不是Al_(3)Fe相,而是一种组成符合化学式Al_(10)CaFe_(2)的三元化合物。通过包晶转变L+Al_(3)Fe→(Al)+Al_(10)CaFe_(2... 详细信息

采用热力学计算和实验技术研究铝角的Al-Ca-Fe体系相图,包括液相面投影图和凝固反应。结果表明,与铝固溶体(Al)平衡的不是Al_(3)Fe相,而是一种组成符合化学式Al_(10)CaFe_(2)的三元化合物。通过包晶转变L+Al_(3)Fe→(Al)+Al_(10)CaFe_(2)(638℃,3.3%Ca和0.5%Fe,摩尔分数)发生从二元化合物到三元化合物的转变。与针状Al_(3)Fe相夹杂物不同,三元化合物的初晶和共晶具有致密的形貌。使用第一性原理计算和X射线衍射分析确定三元化合物Al_(10)CaFe_(2)的晶格结构。此外,近共晶合金Al-6%Ca-1%Fe(质量分数)在500~600℃退火后具有细晶组织,过量相的总体积分数约为25%。因此,Al-Ca-Fe体系可用于制造新的铝基复合合金。

关键词： Al-Ca合金金属间化合物相图相变显微组织铝基复合材料

B-L model with D_(4)×Z_(4)×Z_(2)symmetry for fermion mass hierarchies and mixings

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Chinese Physics C 2024年第6期48卷 11-30页

作者： v.v.vien Department of Physics Tay Nguyen UniversityDaklakVietnam

We constructed a gauge B-L model with D_(4)×Z_(4)×Z_(2)symmetry to explain the quark and lepton mass hierarchies and their mixings with realistic CP phases via the type-I seesaw mechanism.Six quark mases,three quark mixing angles,and the CP phase in the quark sector take the central values whereas Yukawa couplings in the quark sector are diluted in a range of difference of three orders of magnitude by the perturbation theory at the first order.Concerning the neutrino sector,a small neutrino mass is achieved by the type-I seesaw mechanism.Both inverted and normal neutrino mass hierarchies are consistent with the experimental data.The predicted sum of neutrino masses for normal and inverted hierarchies,the effective neutrino masses,and the Dirac CP phase are also consistent with recently reported limits.

关键词： flavor symmetries quark and lepton masses and mixing extensions of electroweak gauge sector neutrino mass and mixing non-standard-model neutrinos right-handed neutrinos D4 discrete symmetry

Gradient-induced long-range optical pulling force based on photonic band gap

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Light(Science & Applications) 2024年第5期13卷 865-874页

作者： Wenlong Lu Alexey v.Krasavin Sheng Lan Anatoly v.Zayats Qiaofeng Dai Guangdong Basic Research Center of Excellence for Structure and Fundamental Interactions of Matter Guangdong Provincial Key Laboratory of Nanophotonic Functional Materials and DevicesSchool of Information and Optoelectronic Science and EngineeringSouth China Normal UniversityGuangzhou 510006China Department of Physics and London Centre for Nanotechnology King’s College LondonLondon WC2R 2LSUK

Optical pulling provides a new degree of freedom in optical manipulation.It is generally believed that long-range optical pulling forces cannot be generated by the gradient of the incident field.Here,we theoretically propose and numerically demonstrate the realization of a long-range optical pulling force stemming from a self-induced gradient field in the manipulated object.In analogy to potential barriers in quantum tunnelling,we use a photonic band gap design in order to obtain the intensity gradients inside a manipulated object placed in a photonic crystal waveguide,thereby achieving a pulling force.Unlike the usual scattering-type optical pulling forces,the proposed gradient-field approach does not require precise elimination of the reflection from the manipulated objects.In particular,the Einstein-Laub formalism is applied to design this unconventional gradient force.The magnitude of the force can be enhanced by a factor of up to 50 at the optical resonance of the manipulated object in the waveguide,making it insensitive to absorption.The developed approach helps to break the limitation of scattering forces to obtain longrange optical pulling for manipulation and sorting of nanoparticles and other nano-objects.The developed principle of using the band gap to obtain a pulling force may also be applied to other types of waves,such as acoustic or water waves,which are important for numerous applications.

关键词： optical waveguide scattering

Active and passive modulation of solar light transmittance in a uniquely multifunctional dual-band single molecule for smart window applications

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Journal of Energy Chemistry 2024年第1期88卷 293-305,I0007页

作者： Pooja v.Chavan Pramod v.Rathod Joohyung Lee Sergei v.Kostjuk Hern Kim Department of Energy Science and Technology Environmental Waste Recycle InstituteMyongji UniversityYonginGyeonggi-do 17058Republic of Korea Department of Chemical Engineering Myongji UniversityYonginGyeonggi-do 17058Republic of Korea Research Institute for Physical Chemical Problems of the Belarusian State University MinskBelarus

Functional materials may change color by heat and electricity separately or simultaneously in smart windows.These materials have not only demonstrated remarkable potential in the modulation of solar radiation but are also leading to the development of indoor environments that are more comfortable and conducive to improving individuals'quality of life.Unfortunately,dual-responsive materials have not received ample research attention due to economic and technological challenges.As a consequence,the broader utilization of smart windows faces hindrances.To address this new generational multistimulus responsive chromic materials,our group has adopted a developmental strategy to create a poly(NIPAM)n-Hv as a switchable material by anchoring active viologen(Hv)onto a phase-changing poly(NIPAM)n-based smart material for better utility and activity.These constructed smart windows facilitate individualistic reversible switching,from a highly transparent state to an opaque state(thermochromic)and a red state(electrochromic),as well as facilitate a simultaneous dual-stimuli response reversible switching from a clear transparent state to a fully opaque(thermochromic)and orange(electrochromic)states.Absolute privacy can be attained in smart windows designed for exclusive settings by achieving zero transmittance.Each unique chromic mode operates independently and modulates visible and near-infrared(NIR)light in a distinct manner.Hence,these smart windows with thermal and electric dual-stimuli responsiveness demonstrate remarkable heat regulation capabilities,rendering them highly attractive for applications in building facades,energy harvesting,privacy protection,and color display.

关键词： Smart windows Thermochromism Electrochromism Energy saving Dual-responsive material

MicroRNAs as potential biomarkers for diagnosis of schizophrenia and influence of antipsychotic treatment

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Neural Regeneration Research 2024年第7期19卷 1523-1531页

作者： Bridget Martinez Philip v.Peplow Department of Pharmacology University of Nevada-RenoRenoNVUSA Department of Medicine University of Nevada-RenoRenoNVUSA Department of Anatomy University of OtagoDunedinNew Zealand

Chara cterized by positive symptoms(such as changes in behavior or thoughts,including delusions and hallu cinations),negative symptoms(such as apathy,anhedonia,and social withdrawal),and cognitive impairments,schizophrenia is a chro nic,severe,and disabling mental disorder with late adolescence or early adulthood onset,Antipsychotics are the most commonly used drugs to treat schizophrenia,but those currently in use do not fully reverse all three types of symptoms characte rizing this condition.Schizophrenia is frequently misdiagnosed,resulting in a delay of or inappropriate treatment.Abnormal expression of microRNAs is connected to brain development and disease and could provide novel biomarkers for the diagnosis and prognosis of schizophrenia.The recent studies reviewed included microRNA profiling in blood-and urine-based materials and nervous tissue mate rials.From the studies that had validated the preliminary findings,potential candidate biomarkers for schizophrenia in adults could be miR-22-3p,-30e-5p,-92a-3p,-148b-5p,-181a-3p,-181a-5p,-181b-5p,-199 b-5p,-137 in whole blood,and miR-130b,-193a-3p in blood plasma.Antipsychotic treatment of schizophrenia patients was found to modulate the expression of certain microRNAs including miR-130b,-193a-3p,-132,-195,-30e,-432 in blood plasma.Further studies are warranted with adolescents and young adults having schizophrenia and consideration should be given to using animal models of the disorder to investigate the effect of suppressing or overexpressing specific microRNAs.

关键词： antipsychotics biomarkers blood exosomes blood plasma brain tissue exosomes brain tissues leukocytes microRNAs neural stem cells olfactory neuroepithelium schizophrenia whole blood