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Gravitational wave footprints from Higgs-portal scalegenesis with multiple dark chiral scalars

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chinese Physics c 2024年第4期48卷 209-221页

作者： He-xu Zhang Shinya Matsuzaki Hiroyuki Ishida center for Theoretical Physics and college of Physics Jilin UniversityChangchun 130012China center for Liberal Arts and Sciences Toyama Prefectural UniversityToyama 939-0398Japan

We discuss the gravitational wave(GW)spectra predicted from the electroweak scalegenesis of the Higgs portal type with a large number of dark chiral flavors,which many flavor QcD would underlie and give the dynamical explanation of the negative Higgs portal coupling required to trigger the electroweak symmetry *** employ the linear-sigma model as the low-energy description of dark many flavor QcD and show that the model undergoes ultra-supercooling due to the produced strong first-order thermal phase transition along the(approximately realized)flat direction based on the Gildener-Weinberg *** through evaluation of the bubble nucleation/percolation,we address the reheating and relaxation processes,which are generically non-thermal and *** the reheating epoch in terms of the e-folding number,we propose proper formulae for the redshift effects on the GW frequencies and signal *** then turns out that the ultra-supercooling predicted from the Higgs-portal scalegenesis generically yields none of GW signals with the frequencies as low as nano Hz,unless the released latent heat is transported into another sector other than reheating the ***,models of this class prefer to give the higher frequency signals and still keeps the future prospected detection sensitivity,like at LISA,BBO,and DEcIGO,*** also find that with large flavors in the dark sector,the GW signals are made further smaller and the peak frequencies *** phenomenological consequences related to the multiple chiral scalars include the prediction of dark pions with the mass much less than TeV scale,which is also briefly addressed.

关键词： gravitational wave electroweak scalegenesis many flavor QcD

Effect of Heat Treatment on Microstructure and Mechanical Properties of Multiscale Sic_p Hybrid Reinforced 6061 Aluminum Matrix composites

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Journal of Wuhan University of Technology(Materials Science) 2024年第1期39卷 174-181页

作者：吴健铭许晓静 ZHANG xu LUO Yuntian LI Shuaidi HUANG Lin Institute for Advanced Manufacturing and Modern Equipment Technology Jiangsu UniversityZhenjiang 212013China

The performance of solid solution aging treatment on aluminum matrix composites prepared by powder metallurgy and reinforced with 6061 aluminum alloy powder as matrix;meanwhile, nano silicon carbide particles(nm Si cp), submicron silicon carbide particles(1 μm Si cp) and Ti particles were studied. The Al/Si cp composite powder was prepared by high-energy ball milling, and then cold-pressed, sintered, hotextruded, and then heat-treated with different solution temperatures and aging times for the extruded composites. Optical microscopy, scanning electron microscopy, energy dispersive X-ray spectroscopy(EDS), X-ray diffractometer(XRD) and extrusion testing were used to analyze and test the microstructure and mechanical properties of aluminum matrix composites. The results show that after the multi-stage solid solution at 530 ℃×2 h+535 ℃×2 h+540 ℃×2 h, the particles are mainly equiaxed grains and uniformly distributed. There is no reinforcement agglomeration, and the surface is dense and the insoluble phase is basically dissolved. In the matrix, the strengthening effect is good, and the hardness and compressive strength are 179.43 HV and 680.42 MPa, respectively. Under this solution process, when the aluminum matrix composites are aged at 170 ℃ for 10 h, the hardness and compressive strength can reach their peaks and increase to 195.82 HV and 721.48 MPa, respectively.

关键词： aluminum matrix composites Si c particles multiscale hybrid enhancement heat treatment mechanical properties

Polyimide covalent organic frameworks as efficient solid-state Li^(+) electrolytes

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Science china chemistry 2024年第5期67卷 1647-1652页

作者： xu Liu Shi Wang Siqi Liu chengfang Liu Xiangchun Li Jian Wu Dazhi Li Shihao xu chongyang Liu 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

covalent organic frameworks(cOFs) are attractive porous crystalline materials with extremely high stability, easy functionalization, and open channels, which are expected to be unique ion conductors/transporters in lithium ion batteries(LIBs). Despite recent advances, low ion conductivity and low transference number, resulting in low charging/discharging rate, low energy density, and short battery life, are the main issues that limit their direct application as solid electrolytes in LIBs. Here, we designed and synthesized a novel polyimide cOF, namely, TAPA-PDI-cOF, with abundant c=O groups, which has been successfully employed as high-performance solid electrolytes by doping TAPA-PDI-cOF and succinonitrile(SN). Both the well-defined nanochannels of cOFs and SN confined in the well-aligned channels restricted the free migration of anions, while c=O on cOFs and cN groups of SN enhanced Li^(+) transport, thus achieving a high ion conductivity of 0.102 m S cm^(-1)at 80 °c and a high lithium-ion transference number of 0.855 at room temperature. According to density functional theory(DFT)calculations, Li-ion migration mainly adopted in-plane transport rather than the axial pathway, which may be due to the shorter hopping distances in the planar pathway. The results suggest an effective strategy for the design and development of all-solidstate ionic conductors for achieving high-performance LIBs.

关键词： lithium ion batteries(LIBs) covalent organic frameworks(cOFs) solid-state ion conductors solid-state electrolytes ion conductivity

Whole-genome resequencing identifies candidate genes and allelic variation in the MdNADP-ME promoter that regulate fruit malate and fructose contents in apple

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Plant communications 2024年第9期5卷 168-183页

作者： Weihong Fu Lin Zhao Wanjun Qiu xu xu Meng Ding Liming Lan Shenchun Qu Sanhong Wang college of Horticulture Nanjing Agricultural UniversityNanjing 210095China xuzhou Institute of Agricultural Sciences in xuhuai Region of Jiangsu Xuzhou 221131China

Soluble sugar and organic acids are key determinants of fruit organoleptic quality and directly affect the commodity value and economic returns of fruit *** performed whole-genome sequencing of the apple varieties Gala and Xiahongrou,along with their F1 hybrids,to construct a high-density bin *** quantitative genetic analysis pinpointed 53 quantitative trait loci(QTLs)related to 11 sugar and acid *** identified a candidate gene,MdNADP-ME,responsible for malate degradation,in a stable QTL on linkage group *** analysis revealed an A/c SNP in the promoter region(MEp-799)that influences binding of the MdMYB2 transcription factor,thereby affecting MdNADP-ME *** our study of various apple genotypes,this SNP has been demonstrated to be linked to malate and fructose *** also developed a dcAPS marker associated with fruit fructose *** results substantiate the role of MdNADP-ME in maintaining the equilibrium between sugar and acid contents in apple fruits.

关键词： apple quantitative trait locus malate degradation sugar content promoter

A review on the chemical speciation and influencing factors of heavy metals in Municipal Solid Waste landfill humus

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Waste Disposal and Sustainable Energy 2024年第2期6卷 209-218页

作者： Qiongyu Sun Bo Sun Defeng Wang Yuyuan Pu Mingxiu Zhan xu xu Jinqing Wang Wentao Jiao college of Metrology and Measurement Engineering China Jiliang UniversityHangzhou 310018Zhejiang ProvinceChina Zhongke Hualu Soil Remediation Engineering co. LtdDezhou 253011Shandong ProvinceChina Zhejiang Environmental Protection Group co. LtdHangzhou 310020Zhejiang ProvinceChina Institute for Thermal Power Engineering Zhejiang UniversityHangzhou 310027Zhejiang ProvinceChina Research center for Eco-Environmental Sciences Chinese Academy of SciencesHaidian District18 Shuangqing RoadBeijing 100085China

Heavy metal pollution in landfill humus can cause serious environmental problems and may endanger soil ecosystems and human *** biological toxicity of heavy metals is not only related to their total amount but also influenced to a greater extent by the distribution of their chemical *** the different chemical speciation and proportions of heavy metals can provide a more comprehensive and accurate understanding of the pollution characteristics and biological toxic-ity of heavy metals in landfill *** on a review of the relevant literature,this paper systematically summarizes the recent research status of typical heavy metal chemical speciation in landfill *** chemical speciation is diverse and *** instance,heavy metals in residual states and organically bound states have little impact on organisms,while heavy metals in exchangeable states and Fe-Mn oxide states can easily migrate and *** chemical speciation of heavy metals is affected by many factors,among which the soil pH and organic matter content are some of the most important ***,the existing gaps in the current research on the chemical speciation of heavy metals in landfills are described and future research directions are *** work provides a theoretical reference for researching the restoration of heavy metal-contaminated humus soil and the resource utilization of humus soil.

关键词： Landflls Humus soil containing heavy metal-chemical speciation Distribution characteristics Influencing factors

Origin of extension twinning-mediated static recrystallization and unique parallel alignment of(0001) poles to transverse direction in Mg-3Al-0.4Mn(mass%) alloy sheet

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Journal of Magnesium and Alloys 2023年第9期11卷 3200-3213页

作者： T.Nakata c.xu L.Geng S.Kamado Nagaoka University of Technology 1603-1KamitomiokaNagaoka 940-2188Japan School of Materials Science and Engineering Harbin Institute of Technology Harbin 150001China

The origin of unique parallel alignment of(0001) poles to transverse direction(TD) was investigated using Mg-3Al-0.4Mn(mass%)alloy sheets rolled with different process conditions. When rolling was performed with intermediate reheating, the alloy showed a sluggish static recrystallization(SRX) behavior during post-annealing, facilitating the nucleation and growth of statically recrystallized grains from extension twins. This resulted in the apparent texture component with the parallel alignment of the(0001) poles to the TD, and the sheet exhibited good ductility for both the rolling direction(RD) and TD. In contrast, continuous rolling without intermediate reheating led to the formation of severely deformed regions near double twins. SRX was promoted at such regions, forming a typical basal textural feature with weak RD-split of the(0001) poles. Although extension twins were formed after the continuous rolling, SRX was facilitated at the severely deformed regions with double twins, and the formation of the unique alignment of the(0001) poles to the TD was suppressed. The RD-split texture led to the large elongation to failure along the RD, while it along the TD decreased owing to the narrow distribution of the(0001)poles toward the TD, resulting in the in-plane anisotropy in ductility.

关键词： Magnesium Rolling Twinning Static recrystallization Texture

Molecular dynamics simulation study of nitrogen vacancy color centers prepared by carbon ion implantation into diamond

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Nanotechnology and Precision Engineering 2024年第3期7卷 71-78页

作者： Wei Zhao Zongwei xu Pengfei Wang Hanyi chen State Key Laboratory of Precision Measuring Technology and Instruments Tianjin UniversityTianjin 300072China Department of Modern Physics University of Science and Technology of ChinaHefei 230026China

Nitrogen vacancy(NV)color centers in diamond have useful applications in quantum sensing andﬂuorescent *** can be gen-erated experimentally by ion implantation,femtosecond lasers,and chemical vapor ***,there is a lack of studies of the yield of NV color centers at the atomic *** the molecular dynamics simulations described in this paper,NV color centers are pre-pared by ion implantation in diamond with pre-doped nitrogen and subsequent *** differences between the yields of NV color centers produced by implantation of carbon(c)and nitrogen(N)ions,respectively,are *** is found that c-ion implantation gives a greater yield of NV color centers and superior location *** effects of different pre-doping concentrations(400–1500 ppm)and implantation energies(1.0–3.0 keV)on the NV color center yield are analyzed,and it is shown that a pre-doping concentra-tion of 1000 ppm with 2 keV c-ion implantation can produce a 13%yield of NV color centers after 1600 K annealing for 7.4 ***,a brief comparison of the NV color center identiﬁcation methods is presented,and it is found that the error rate of an analysis utiliz-ing the identify diamond structure coordination analysis method is reduced by about 7%compared with conventional identiﬁcation+methods.

关键词： NV color center Ion implantation Molecular dynamics(MD)simulation Yield enhancement

Electrochemical Mono-Deuterodefluorination of Trifluoromethyl Aromatic compounds with Deuterium Oxide

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ccS chemistry 2024年第1期6卷 230-240页

作者： Jie Sheng xu cheng Institute of chemistry and Biomedical Sciences Jiangsu Key Laboratory of Advanced Organic MaterialsSchool of Chemistry and Chemical EngineeringNanjing UniversityNanjing 210023 State Key Laboratory of Elemento-Organic chemistry Nankai UniversityTianjin 30071

The deuterodifluoromethyl group cF_(2)D combines the structural features of cF_(3) and cD_(3) groups,finding wide applications in diverse pharmaceutical *** this work,the electrochemical monodeuterodefluorination of Ar-cF_(3) to Ar-cF_(2)D is achieved with an unreported deuterium atom transfer-coupled electron transfer pathway using D_(2)O as the only D source for the first time.A series of Ar-cF_(3) substances,including commercial pharmaceuticals,were converted to corresponding cF_(2)D products in up to 91% yield and 97% D-incorporation.A variety of functional groups,including pyridine,pyrrole,furan,thiophene,borate,thio ether,amine,amide,sulfonamide,and halide,are well tolerated in this protocol.t-BuOLi was an essential reagent to achieve chemoselective mono-defluorination.

关键词： electrochemistry c-F activation fluorinecontaining drugs deuterated drugs deuterium oxide

Tailoring sulfur-doped and nitrogen-defective carbon nitride nanosheets for efficient photo-controlled radical polymerizations

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Science china chemistry 2024年第7期67卷 2325-2334页

作者： xue Li Meng Kai xu Yuan Huang Tao cai Key Laboratory of Biomedical Polymers of Ministry of Education College of Chemistry and Molecular SciencesWuhan UniversityWuhan 430072China Wuhan University Shenzhen Research Institute Shenzhen 518057China

Despite the challenges that remain,the synergistic adjustment of various microstructures and photochemical parameters of graphitic carbon nitride(g-c_(3)N_(4))in photocatalytic reactions holds promises for improving catalytic efficiency and reducing energy ***,sulfur-doped and nitrogen-defective g-c_(3)N_(4)(n-Sc_(3)N_(x))nanosheets were designed and elaborately *** resultant n-Sc_(3)N_(x)possessed a precisely defined 2D layer structure with extensive porosity and incremental specific surface *** photoinduced electron transfer-reversible addition-fragmentation chain transfer(PET-RAFT)polymerization of vinyl monomers with low dispersity,excellent temporal control and high chain-end fidelity was achieved under mild blue light irradiation in a nondegassed *** to their ultrathin nanostructures with nitrogen defects and sulfur dopants,n-Sc_(3)N_(x)was capable of catalyzing RAFT polymerization in aqueous solutions at significantly accelerated rates,which were nearly 8 times faster compared to bulk g-c_(3)N_(4).The ease of separation and efficient reusability in subsequent polymerizations was enabled by the heterogeneous nature of n-Sc_(3)N_(x).The appeal of this approach was illustrated by the fact that utilizing a reusable and metal-free photocatalyst in aqueous environments allowed for the synthesis of polymers with molecular weight up to 300 kg mol^(-1) and a dispersity of 1.32.

关键词： graphitic carbon nitride nitrogen defects sulfur dopants PET-RAFT polymerization recyclability