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Equitable Vertex Arboricity Conjecture Holds for Graphs with Low Degeneracy

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Acta Mathematica Sinica,English Series 2021年第8期37卷 1293-1302页

作者： Xin ZHANG Bei NIU Yan li bi li School of Mathematics and Statistics Xidian UniversityXi’an 710071P.R.China

The equitable tree-coloring can formulate a structure decomposition problem on the communication network with some security ***,an equitable tree-Zc-coloring of a graph is a vertex coloring using k distinct colors such that every color class induces a forest and the sizes of any two color classes differ by at most *** this paper,we show some theoretical results on the equitable tree-coloring of graphs by proving that every d-degenerate graph with maximum degree at most Δ is equitably tree-fc-colorable for every integer k≥(Δ+1)/2 provided that Δ≥9.818d,confirming the equitable vertex arboricity conjecture for graphs with low degeneracy.

关键词： Equitable coloring tree-coloring vertex arboricity degeneracy

Effect of Zr on microstructure and properties of Cu–15Cr alloy

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Journal of Central South University 2017年第12期24卷 2757-2766页

作者： TIAN Wei bi li-ming College of Science University of Shanghai for Science and Technology Shanghai 200093 China University of Shanghai for Science and Technology Shanghai 200093 China

In order to study the effect of Zr on the microstructure and isothermal annealing performance of Cu–Cr in situ composites, Cu–15 Cr and Cu–15 Cr–0.24 Zr alloys were prepared by means of vacuum medium frequency induction melting technology. The two kinds of test alloys with deformation of 3.79 were subjected to isothermal annealing test. The effects of Zr on the as-cast microstructure, the isothermal annealing structure and the tensile fracture morphology of Cu–15 Cr alloy were studied by means of scanning electron microscopy(SEM), energy dispersive spectroscopy(EDS) and transmission electron microscopy(TEM). The results show that the addition of Zr leads to the formation of homogeneous and fine Cu Zr intermetallic compounds, which suppresses the formation electron microscopy of eutectic Cr phase and makes the eutectic Cr content much lower than that of Cu–15 Cr alloy. The recrystallization temperature of the Cu matrix is increased, and it is maintained at a fine equiaxed crystal at 400 °C. After isothermal annealing at 400 °C for 220 h, the tensile strength, electrical conductivity and elongation of the test alloy containing Zr were 720 MPa, 68% IACS and 6.7%, respectively; while the tensile strength, electrical conductivity and elongation of the test alloys without Zr were 488 MPa, 70% IACS and 12.4%, respectively.

关键词： Cu–Cr–Zr alloy in-situ composites isothermal annealing CuZr intermetallic compounds mechanical properties

Rice miR394 suppresses leaf inclination through targeting an F-box gene, LEAF INCliNATION 4

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Journal of Integrative Plant biology 2019年第4期61卷 406-416页

作者： li Qu li-bi lin Hong-Wei Xue National Key Laboratory of Plant Molecular Genetics CAS Center for Excellence in Molecular Plant Sciences Shanghai Institute of Plant Physiology and Ecology the Chinese Academy of Sciences University of the Chinese Academy of Sciences

Rice leaf inclination is an important agronomic trait, closely related to plant architecture and *** of genes controlling leaf inclination would assist in crop improvement. Although various factors,including the plant hormones auxin and brassinosteroids,have been shown to regulate lamina joint development,the role of microRNAs in regulating leaf inclination remains largely unknown. Here, we functionally characterize the role of rice miR394 and its target, LEAF INCliNCATION 4(LC4), which encodes an F-box protein, in the regulation of leaf inclination. We show that miR394 and LC4 work,antagonistically, to regulate leaf lamina joint development and rice architecture, by modulating expansion and elongation of adaxial parenchyma cells. Suppressed expression of miR394, or enhanced expression of LC4,results in enlarged leaf angles, whereas reducing LC4 expression by CRISPR/Cas9 leads to reduced leaf inclination, suggesting LC4 as candidate for use in rice architecture improvement. LC4 interacts with SKP1, a component of the SCF E3 ubiquitin ligase complex, and transcription of both miR394 and LC4 are regulated by auxin. Rice plants with altered expression of miR394 or LC4 have altered auxin responses, indicating that the miR394-LC4 module mediates auxin effects important for determining rice leaf inclination and architecture.

关键词： Rice miR394 F-box gene LEAF INCliNATION 4

Simulation of proton–neutron collisions in inverse kinematics and its possible application

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Nuclear Science and Techniques 2021年第4期32卷 60-69页

作者： bi-Lu li Gang-lin Yu Shi-Fei Shen Department of Engineering Physics Tsinghua UniversityBeijing 100084China

Neutrons have played a vital role in many nuclear physics *** some cases,the inverse kinematics of neutrons colliding with other nuclei are also worth *** this study,the inverse kinematics of thermal neutrons colliding with high-energy protons is simulated by using the Monte Carlo *** neutrons are taken as target particles,whereas protons are incident *** simulation implies that,after collision,the energy of the output neutron at 0°equals the energy of the incident proton.A possible application of the result is proposed that might yield single-energy *** key parameters of the conceptual design were evaluated,demonstrating that the design may reach high-neutron-energy resolution.

关键词： Inverse kinematics Mono-energetic neutron Proton Monte Carlo

Palladium,Platinum and Gold Concentrations in Fengshan Porphyry Cu-Mo Deposit,Hubei Province,China

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Acta Geologica Sinica(English Edition) 2009年第5期83卷 893-901页

作者： WANG Minfang DENG Xiaodong bi Shijian li Zhanke Faculty of Earth Resources China University of Geosciences Wuhan 430074 China

The Fengshan porphyry-skarn copper-molybdenum （Cu-Mo） deposit is located in the south-eastern Hubei Province in east China. Cu-Mo mineralization is hosted in the Fengshan granodiorite porphyry stock that intruded the Triassic Daye Formation carbonate rocks in the early Cretaceous （-140 Ma）, as well as the contact zone between granodiorite porphyry stock and carbonate rocks, forming the porphyry-type and skaru-type association. The Fengshan granodiorite stock and the immediate country rocks are strongly fractured and intensely altered by hydrothermal fluids. In addition to intense skarn alteration, the prominent alteration types are potassic, phyllic, and propylitic, whereas argiilation is less common. Mineralization occurs as veins, stock works, and disseminations, and the main ore minerals are chalcopyrite, pyrite, molybdenite, bornite, and magnetite. The contents of palladium, platinum and gold （Pd, Pt and Au） are determined in nine samples from fresh and mineralized granodiorite and different types of altered rocks. The results show that the Pd content is systematically higher than Pt, which is typical for porphyry ore deposits worldwide. The Pt content ranges from 0.037 tol.765 ppb, and the Pd content ranges between 0.165 and 17.979 ppb. Pd and Pt are more concentrated in porphyry mineralization than skarn mineralization, and have negative correlations with Au. The reconnaissance study presented here confirms the existence of Pd and Pt in the Fengshan porphyry-skarn Cu-Mo deposit. When compared with intracontinent and island arc geotectonic settings, the Pd, Pt, and Au contents in the Fengshan porphyry Cu-Mo deposit in the intracontinent is lower than the continental margin types and island are types. A combination of available data indicates that Pd and Pt were derived from oxidized alkaline magmas generated by the partial melting of an enriched mantle source.

关键词： porphyry skarn copper-molybdenum palladium platinum gold Fengshan China

Application and efficacy of reconstructing forked corpus spongiosum in distal/midshaft hypospadias repair

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Asian Journal of Andrology 2021年第1期23卷 47-51页

作者： bin Zhang Yun-li bi Shuang-Sui Ruan Department of Pediatric Urology Children's Hospital of Fudan UniversityShanghai 201102China

We reviewed our experience in reconstructing forked corpus spongiosum(FCS)in distal/midshaft hypospadias repair and analyzed the efficacy of this surgical *** August 2013 to December 2018,137 consecutive cases of distal/midshaft hypospadias operated by the same surgeon in Urology Department,Children’s Hospital of Fudan University(Shanghai,China),were retrospectively ***-four patients who underwent routine tubularized incised plate(TIP)or onlay island flap(ONLAY)surgery were included in the nonreconstructing group,and 73 patients who underwent reconstructing FCS during TIP or ONLAY surgery were included as the reconstructing ***-eight cases underwent TIP,and 26 underwent ONLAY in the nonreconstructing group,with a median follow-up of 44(range:30-70)***-seven cases underwent TIP,and 46 underwent ONLAY in the reconstructing group,with a median follow-up of 15(range:6-27)*** the nonreconstructing/reconstructing groups,the mean age at the time of surgery was 37.55(standard deviation[s.d.]:29.65)/35.23(s.d.:31.27)months,the mean operation duration was 91.95(s.d.:12.17)/93.84(s.d.:14.91)min,the mean neourethral length was 1.88(s.d.:0.53)/1.94(s.d.:0.53)cm,and the mean glans width was 11.83(s.d.:1.32)/11.56(s.d.:1.83)***(18.8%)/5(6.8%)postoperative complications occurred in the nonreconstructing/reconstructing *** included fistula(5/2),glans dehiscence(3/0),diverticulum(1/2),residual chordee(3/0),and meatus stenosis(0/1)in each *** was a significant difference in the overall rate of complications(P=0.035).These results indicate that the technique of reconstructing FCS provides excellent outcomes with fewer complications in distal/midshaft hypospadias repair.

关键词： complications distal/midshaft hypospadias forked corpus spongiosum glans tilt

Synthesis of visible-light-driven TiO_(2) yolk-shell spheres with {001} facets dominated mesoporous shells

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Chinese Chemical Letters 2013年第3期24卷 260-263页

作者： Hui Wang bi-li Wang Shu-Yun Ma Institute of Science PLA University of Science&TechnologyNanjing 21101China

Anatase phase visible-light-driven TiO_(2) yolk-shell spheres with the size of ca.1-2 um have been synthesized with the combination of solvothermal and heat treatment ***,SEM,TEM,XPS,and PL analysis were used to examine structure and properties of the *** N species and Ti3+centers introduced into the as-prepared photocatalyst can enhance the visible light absorption *** mesoporous shell of the prepared photocatalyst,which promotes the pollutant adsorption ability,consists of the high-reactive[001]facets dominated *** to the unique structure,it is also observed that the as-prepared visible-light-driven TiO_(2) yolk-shell spheres exhibit a sunerinr nhnrncatalvtic activity for organic dyes decomposition than the well-known P25.

关键词： Titanium dioxide {001}Facet Photocatalysis Visible light

Metal-Catalyzed Substrate-Directed Enantioselective Functionalization of Unactivated Alkenes

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Chinese Journal of Chemistry 2019年第11期37卷 1174-1180页

作者： Zi-Xuan Wang Xiao-Yan Bai bi-Jie li Center of Basic Molecular Science(CBMS) Department of ChemistryTsinghua UniversityBeijing 100084China

Alkenes are versatile compounds that are available on large scales in industry or through chemical *** functionalization of unactivated alkenes in a chemo-,regio-,diastereo-and enantioselective fashion is a highly sought-after goal in organic ***-directed enantioselective functionalization of unactivated alkenes provides an important strategy to achieve this *** a functional group on the alkene substrate as a native coordinating group,a two-point binding mode of the substrate to the metal center enables effective control of regio-;diastereo-and *** this strategy,a variety of enantioselective functionalization methods have been developed *** recent advances in this area are highlighted here.

关键词： synthesis. enantioselective versatile

Cryptorchid testicular torsion in children characteristics and treatment outcomes

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Asian Journal of Andrology 2021年第5期23卷 468-471页

作者： Hai-Jun Zhong liang-Feng Tang Yun-li bi Department of Pediatric Urology Children's Hospital of Fudan UniversityShanghai 201102China.

This study aimed to review and compare the characteristics and treatment outcomes of cryptorchid testicular torsion in pre-and postpubertal *** reviewed the clinical data of 22 patients with testicular torsion complicated by cryptorchidism who were treated between January 2010 and December *** were categorized into prepubertal(1 month to 9 years;n=12)and postpubertal groups(10-16 years;n=10).The age at presentation,clinical presentations,physical examination,and operation outcomes were *** common clinical presentations in both groups were inguinal pain and a tender inguinal *** in the prepubertal group were significantly more likely to present with restlessness(33.3%)than those in the postpubertal group(0%;P-0.044).After detorsion,testicular blood flow recovered during surgery in 25.0%of the prepubertal and 80.0%of the postpubertal patients(P=0.010).Orchiectomy was required in 50.0%of the prepubertal and 20.0%of the postpubertal patients(P=0.145).Of the 22 patients with follow-up data,the rates of testicular salvage were significantly different,at 16.7%in the prepubertal patients and 60.0%in the postpubertal patients(P=0.035).Cryptorchid testicular torsion has various *** an empty hemiscrotum and a painful groin mass were common in both groups,restlessness was more prevalent in the prepubertal patients during early testicular torsion onset than that in the postpubertal ***,the testicular salvage rate was significantly lower in the prepubertal patients than that in the postpubertal patients.

关键词： children cryptorchidism testicular torsion