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The dusty and extremely red progenitor of the typeⅡsupernova 2023ixf in Messier 101

Science China(Physics,Mechanics & Astronomy) 2024年第1期67卷 160-172页

作者： Danfeng Xiang Jun mo lingzhi Wang Xiaofeng Wang Jujia Zhang han lin Lifan Wang Department of Physics Tsinghua UniversityBeijing 100084China South America Center for Astronomy National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China Beijing Planetarium Beijing Academy of Sciences and TechnologyBeijing 100044China Yunnan Observatories Chinese Academy of SciencesKunming 650216China Key Laboratory for the Structure and Evolution of Celestial Objects Chinese Academy of SciencesKunming 650216China International Centre of Supernovae Yunnan Key LaboratoryKunming 650216China Mitchell Institute for Fundamental Physics and Astronomy Texas A&M UniversityCollege StationTX 77843USA

Stars with initial masses in the range of 8-25 solar masses are thought to end their lives as hydrogen-rich supernovae(SNeⅡ).Based on the pre-explosion images of Hubble space telescope(HST)and Spitzer space telescope,we place tight constraints on the progenitor candidate of type IIP SN 2023ixf in Messier *** of the spectral energy distribution(SED)of its progenitor with dusty stellar spectral models results in an estimation of the effective temperature as 3091+*** luminosity is estimated as lg(L/L⊙)~4.83,consistent with a red supergiant(RSG)star with an initial mass of 12-1+2M⊙.The derived mass loss rate(6×10^(-6)-9×10^(-6)M⊙yr^(-1))is much lower than that inferred from the flash spectroscopy of the SN,suggesting that the progenitor experienced a sudden increase in mass loss when approaching the final *** the infrared bands,significant deviation from the range of regular RSGs in the color-magnitude diagram and period-luminosity space of the progenitor star indicates enhanced mass loss and dust *** with new evidence of polarization at the early phases of SN 2023ixf,such a violent mass loss is likely a result of binary interaction.

关键词： stellar evolution mass loss red supergiants infrared emission supernovae

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Short Cycle Structure of Graphs on Surfaces (1)-the Uniqueness Theorems

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Acta Mathematicae Applicatae Sinica 2008年第4期24卷 677-680页

作者： han Ren mo Deng Department of Mathematics East China Normal University Shanghai 200062 China

In this paper we investigate cycle base structures of a （weighted） graph and show that much information of short cycles is contained in a MCB （minimum cycle base）. After setting up a Hall type theorem for base-transformation, we give a sufficient and necessary condition for a cycle base to be a MCB. Further more, we show that the structure of MCB in a （weighted） graph is unique. In the case of nonnegative weight, every pair of MCB have the same number of k-cycles for each integer k ≥ 3. The property is also true for those having longest length （although much work has been down in evaluating MCB, little is known for those having longest length）.

关键词： Cycle base facial cycle graph embedding

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Mitochondrial DNA diversity and origin of indigenous pigs in South China and their contribution to western modern pig breeds

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Journal of Integrative Agriculture 2019年第10期18卷 2338-2350页

作者： WANG Chen CHEN Yao-sheng han Jian-lin mo De-lin LI Xiu-jin LIU Xiao-hong State Key Laboratory of Biocontrol School of Life SciencesSun Yat-sen UniversityGuangzhou 510006P.R.China CAAS-ILRI Joint Laboratory on Livestock and Forage Genetic Resources Institute of Animal ScienceChinese Academy of Agricultural SciencesBeijing 100193P.R.China International Livestock Research Institute (ILRI) Nairobi 00100Kenya

Indigenous pigs in South China are valuable genetic resources with many specific and unique characters, which have played an important role in the establishment of some western modern pig breeds. However, the origin and genetic diversity of indigenous pigs in South China have not been fully understood. In the present study, we sequenced 534 novel mitochondrial DNA (mtDNA) D-loop and assembled 54 complete mitogenome sequences for all 17 indigenous pig breeds from Fujian, Guangdong, Guangxi and Hainan in South China. These data were analyzed together with previously published homologous sequences relevant to this study. We found that all 13 coding genes of the mitogenomes were under purifying selection, but ND1 had the most variable sites and CYTB contained the most non-synonymous SNPs. Phylogenetic analysis showed that all indigenous pigs in South China were clustered into the D haplogroup with D1a1, D1b, D1c and D1e sub-haplogroups found to be dominant. Haplotype and nucleotide diversities of D-loop sequences ranged from 0.427 to 0.899 and from 0.00342 to 0.00695, respectively, among which all pigs in Guangdong had the lowest diversity. The estimates of pairwise FST, gene flow (Nm) and genetic distance (Da) indicated that most of these indigenous pig breeds differentiated from each other significantly (Pmong the western modern breeds, Berkshire and Yorkshire had significant Asian matrilineal footprints from indigenous pigs in South China, especially the Spotted pigs distributed in Guangdong and Guangxi. The neutrality test (Fu’s FS) indicated that indigenous pigs from Fujian and Guangxi had gone through recent population expansion events (Pmost likely derived from the Mekong region and the middle and downstream regions of Yangtze River through Guangxi and Fujian. Our findings provide a complete and in-depth insight on the origin and distribution pattern of maternal genetic diversity of indigen

关键词： pig South China mitogenome D-loop genetic diversity

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Approximate Solution for Mechanism of Thermally and Wind-driven Ocean Circulation

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Chinese Geographical Science 2010年第5期20卷 383-388页

作者： mo Jiaqi lin Wantao lin Yihua Anhui Normal University Wuhu 241000 China State Key Laboratory of Numerial modeling for Atmospheric Sciences and Geophysical Fluid Dynamics Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China Division of Computational Science E-Institutes of Shanghai Universities at Shanghai Jiaotong University Shanghai 200240 China

The thermally and wind-driven ocean circulation is a complicated natural phenomenon in the atmospheric physics. Hence we need to reduce it using basic models and solve the models using approximate methods. A non-linear model of the thermally and wind-driven ocean circulation is used in this paper. The results show that the zero solution of the linear equation is a stable focus point, which is the path curve trend origin point as time (t) trend to infinity. By using the homotopic mapping perturbation method, the exact solution of the model is obtained. The homotopic mapping perturbation method is an analytic solving method, so the obtained solution can be used for analytic operating sequentially. And then we can also obtain the diversified qualitative and quantitative behaviors for corresponding physical quantities.

关键词： global climate atmosphere-ocean oscillation homotopic mapping approximate solution

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Comparative study on the passivation layers of copper sulphide minerals during bioleaching

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International Journal of Minerals,Metallurgy and Materials 2012年第10期19卷 886-892页

作者： Kai-bin Fu Hai lin Xiao-lan mo han Wang Hong-wei Wen Zi-long Wen School of Civil and Environmental Engineering University of Science and Technology Beijing Beijing 100083 China Key Laboratory of Solid Waste Treatment and Resource Recycle (Ministry of Education) Southwest University of Science and Technology Mianyang 621010 China

The bioleaching of copper sulphide minerals was investigated by using A. ferrooxidans ATF6. The result shows the preferential order of the minerals bioleaching as djurleite〉bomite〉pyritic chalcopyrite〉covellite〉porphyry chalcopyfite. The residues were characterized by X-ray diffraction （XRD） and scanning electron microscopy （SEM）. It is indicated that jarosite may not be responsible for hindered disso- lution. The elemental sulfur layer on the surface of pyritic chalcopyrite residues is cracked. The compact surface layer of porphyry chalcopy- rite may strongly hinder copper extraction. X-ray photoelectron spectroscopy （XPS） further confirms that the passivation layers of covellite, pyritic chalcopyrite, and porphyry chalcopyrite are copper-depleted sulphide Cu4S11, S8, and copper-rich iron-deficient polysulphide CtuFe2S9, resoectivelv. The ability of these oassivation layers was found as Cu4Fe2S9〉Cu4S11〉S8〉iarosite.

关键词： copper ore treatment copper sulphide bioleaching passivation

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A new species of Zanclognatha Lederer and three new records of the families Erebidae and Noctuidae(Lepidoptera,Noctuoidea)from Korea,with notes on larval feeding habits

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Journal of Forestry Research 2021年第3期32卷 1235-1240页

作者： Kang-Won Lee Joon-mo Koo Jae-Dong Kim Hui-lin han Kyu-Tek Park Holoce Ecosystem Conservation Research Institution HoengseongGangweon Province 225-841Republic of Korea Department of Plant Medicine Chungbuk National UniversityCheongju28644Republic of Korea Department of Applied Biology College of Agriculture and Life ScienceChungnam National UniversityDaejeon 34134Republic of Korea School of Forestry Northeast Forestry UniversityHarbin 150040China Key Laboratory of Sustainable Forest Ecosystem Management-Ministry of Education Northeast Forestry UniversityHarbin 150040People’s Republic of China Bioresource and Environmental Center Incheon National UniversityIncheon 22012Republic of Korea

A new species of Zanclognatha Lederer,1857 of the family Erebidae,*** sp.n.,one species of Family Erebidea,Asota egens(Walker,1854)and two species of Family Noctuidae:Meganephria retinea Gyulai and Ronkay,1999 and Amphipyra subrigua Bremer and Grey,1853,are reported for the first time from *** addition,larval feeding habits with their host plants for three species are newly recognized from *** of adults,larvae for Zanclognatha querciella and Meganephria retinea,and the genitalia of male or female for all species are provided.

关键词： Host plants New species New records Korean peninsula Taxonomy

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Memristor initial-boosted coexisting plane bifurcations and its extreme multi-stability reconstitution in two-memristor-based dynamical system

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Science China(Technological Sciences) 2020年第4期63卷 603-613页

作者： BAO han CHEN mo WU HuaGan BAO BoCheng School of Information Science and Engineering Changzhou UniversityChangzhou 213164China

Initial-dependent extreme multi-stability and offset-boosted coexisting attractors have been significantly concerned *** paper constructs a novel five-dimensional(5-D)two-memristor-based dynamical system by introducing two memristors with cosine memductance into a three-dimensional(3-D)linear autonomous dissipative *** theoretical analyses and numerical plots,the memristor initial-boosted coexisting plane bifurcations are found and the memristor initial-dependent extreme multi-stability is revealed in such a two-memristor-based dynamical system with plane ***,a dimensionality reduction model with the determined equilibrium is established via an integral transformation method,upon which the memristor initial-dependent extreme multi-stability is reconstituted theoretically and expounded ***,physically circuit-implemented PSIM(power simulation)simulations are carried out to validate the plane offset-boosted coexisting behaviors.

关键词： memristor-based system memristor initial coexisting plane bifurcations extreme multi-stability

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Breaking the structural symmetry of active sites in zeolite imidazolate framework for enhanced CO2 photoreduction

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Science China Chemistry 2025年

作者： Yupeng han Yayu Yan Qiaohong Li Xin Wu Fei Wang Jian Zhang State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of Matter Chinese Academy of Sciences University of Chinese Academy of Sciences College of Chemistry Fuzhou University

Adjusting the structure and composition of active sites is a highly effective method for activating linear ***, precise control of interfacial chemistry within molecular-scale environments presents a significant challenge in heterogeneous catalysis. In our study, we present symmetry-broken mo-O-Co triple-atom active sites within the hybrid zeolite imidazole framework HZIF-Como. These sites disrupt the electronic balance and create a weak built-in electric field, thus promoting photocatalytic CO2reduction. The CO yield over HZIF-Como is improved to 3.1 mmol g-1h-1, which is over four times higher than the parent cobalt-imidazole framework MAF-6-Co. Both experimental and theoretical studies indicate that electronic modulation through the symmetry-breaking mo-O-Co moiety acts as an organizing knob to accelerate charge separation and result in more carriers participating in the catalytic reaction. This work provides important insights into optimizing site-related electronic structures for targeted photocatalytic reactions.

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RNA-based nanomedicines and their clinical applications

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Nano Research 2023年第12期16卷 13182-13204页

作者： lin-Jia Su Zi-han Ji mo-Xi Xu Jia-Qing Zhu Yi-Hai Chen Jun-Fei Qiao Yi Wang Yao-Xin lin CAS Key Laboratory for Biomedical Effects of Nanomaterials and Nanosafety National Center for Nanoscience and Technology(NCNST)Beijing 100190China University of Chinese Academy of Sciences(UCAS) Beijing 100149China Department of Breast Surgery Harbin Medical University Cancer HospitalHarbin 150081China School of Chemical and Environmental Engineering Wuhan Polytechnic UniversityWuhan 430023China Institute of Bioengineering and Institute of Materials Science&Engineering École Polytechnique Fédérale de Lausanne(EPFL)Lausanne1015Switzerland

RNA-based nanomedicines encompass a range of therapeutic approaches that utilize RNA molecules or molecules that target RNAs for the treatment or prevention of *** include antisense oligonucleotides(ASOs),small interfering RNAs(siRNAs),endogenous microRNAs(miRNAs),messenger RNAs(mRNAs),clustered regularly interspersed short palindromic repeats-associated protein 9(CRISPR/Cas9),single guide RNAs(sgRNAs),as well as RNA *** therapeutic agents exert their effects through various mechanisms such as gene inhibition,addition,replacement,and *** advancement of RNA biology and the field of RNA therapy has paved the way for the development and utilization of RNA-based nanomedicine in human *** remarkable example of RNA-based nanomedicine is the mRNA-based vaccines including mRNA-1273(moderna)and BNT162b2(Pfizer/BioNTech)that have been successfully employed in response to the coronavirus disease 2019(COVID-19)*** review aims to highlight the advantages of RNA-based nanomedicines,provides an overview of significant developments in delivery systems,elucidates the molecular mechanisms of action underlying RNA-based nanomedicines,and discusses their clinical ***,the review will address the existing challenges and innovations in delivery platforms while exploring the future possibilities for these promising RNA-based nanomedicines.

关键词： RNA-based nanomedicine conjugate-based delivery system nanoparticle-based delivery system clinical trial

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Feasibility Analysis of the Operation Strategies for Combined Cooling, Heating and Power Systems (CCHP) based on the Energy-Matching Regime

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Journal of Thermal Science 2020年第5期29卷 1149-1164页

作者： FENG Lejun DAI Xiaoye mo Junrong SHI lin Key Laboratory for Thermal Science and Power Engineering of Ministry of Education Department of Energy and Power EngineeringTsinghua UniversityBeijing 100084China

Although numerous studies have considered the two traditional operation strategies:following the electric load(FEL)and following the thermal load(FTL),for combined cooling,heating,and power(CCHP)systems in different case studies,there are limited theoretical studies on the quantification methods to assess the feasibility of these two strategies in different load demands ***,instead of a case study,we have undertaken a theoretical analysis of the suitable application scenarios for FEL and FTL strategies based on the energy-matching performance between systems'provision and users'*** compare the calculation models of energy saving rate(ESR)for FEL and FTL strategies in the left and right sub-regions of the energy-supply curve,a comprehensive parameter(^)that combines three inherently influential factors(off-design operation parameter,energy-matching parameter,and install capacity coefficient)is defined to determine the optimal installed capacity and feasibility of FEL or FTL strategies *** results indicate that greater value of x contribute to a better energy saving performance,and FEL strategy shows better performance than FTL in most load demands scenarios,and the optimal installed capacity occurs when the load demand points were located in different regions of the energy-supply ***,taking a hotel in Beijing as an example,the value of the optimal install capacity coefficient is 0.845 and the FEL strategy is also suggested,and compared to the maximum install capacity,the average values of the ESR on a typical summer day,transition season,and winter can be enhanced by 3.9%,8.8%,and 1.89%,respectively.

关键词： combined cooling heating and power systems(CCHP) energy-matching performance operation strategies comprehensive parameter energy saving performance

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