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The saproxylic beetle assemblage associated with different host trees in Southwest China

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Insect Science 2008年第3期15卷 251-261页

作者： Jie Wu Xiao-Dong yu Hong-zhang zhou Institute of Zoology Chinese Academy of Sciences Beijing China

Dead wood is a habitat for many insects and other small animals, some of which may be rare or endangered and in need of effective protection. In this paper, saproxylic beetle assemblages associated with different host trees in the subtropical forests in southwestern China were investigated. A total of 277 species （1 439 specimens） in 36 beetle families were collected from 117 dead wood samples, of which 101 samples were identified and respectively belonged to 12 tree genera. The number of saproxylic beetle species varied greatly among logs of different tree genera, with the highest diversity on logs of Juglans. Generally, broad-leaved trees had a higher richness and abundance of saproxylic species than coniferous trees. Cluster analysis revealed that assemblages from broad-leaved tree genera were generally similar （except for Betula） and assemblages from coniferous trees formed another distinct cluster. The subsequent indicator analysis proposed that there are different characteristic species for different cluster groups of host tree genera. In our study, log diameter has no positive influence on beetle species density. Conversely, comparisons of individual-based rarefaction curves suggested that beetle species richness was highest in the small diameter class both in coniferous and broad-leaved tree genera. With increased wood decay, proportion of habitat specialists （saproxylic beetles living on one tree genus） decreased, whereas proportion of habitat generalists （living on more than three tree genera） increased. The beetle species density was found to be higher in early stages, and decreased in later stages as well. A negative influence of altitude on saproxylic beetle species richness and abundance was detected. It was indicated that different tree genera and altitudes possibly display cross effects in modulating the altitudinal distribution and host preference of the beetles.

关键词： China host trees Saproxylic beetle subtropical forest

Structural properties and crystal orientation of polycrystalline Gd films

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Rare Metals 2023年第4期42卷 1414-1419页

作者： yu-zhou zhang Shi-Rong zhang Dun-Bo yu Yang Luo Ning-Tao Quan Wen-Long Yan Kuo-She Li National Engineering Research Center for Rare Earth Materials General Research Institute for Nonferrous MetalsBeijing100088China Grirem Advanced Materials Co.Ltd. Beijing100088China

To get a systematic understanding about dependence of deposition conditions on properties of Gd films,a series of Gd films were prepared under different Ar gas pressures:0.5,0.7,1.0,and 1.5 Pa,and another series of Gd films were prepared under different substrate temperatures:25,100,200,350,and 500℃.The effects of the deposition time,Ar pressure,and substrate temperature on microstructures and crystal orientation were investigated by grazingincidence X-ray diffraction(GIXRD)and transmission electron microscopy(TEM).The experimental results show that low Ar pressure and plenty deposition time will contribute to the formation of Gd hcp phase,which has better magnetic properties such as higher Curie temperature and bigger magnetic moment,and high substrate temperature can diminish the inner stress in Gd films and promote lattice parameters closer to those of the ideal Gd hcp-structure.

关键词： Thin film Size effects Grain orientation Heavy rare earth Nanocrystal Microstructure

Synthesis and Crystal Structure of rac-N,N-Dimethyl-1- ferrocenylethylamine Hydrochloride

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有机化学 2004年第z1期24卷 23-24页

作者： zhang,yu-Mei zhou,Zhi-Ming yu,Cong-Xuan College of Sciences Hebei University of Science and Technology Shijiazhuang 050016 School of Chemical Engineering and the Environment Beijing Institute of Technology Beijing 100081 School of Chemical Engineering and the Environment Beijing Institute of Technology Beijing 100081

　　Ferrocene with planar chirality are of increasing importance in the synthesis of chiral ligands used in asymmetric catalysis and asymmetric synthesis.[1～3] To prepare Ugi type of chiral base, the most common meth... 详细信息

关键词： asymmetric synthesis asymmetric catalysis planar chirality chiral ligands used in type of

Oxidation and thermal fatigue of EB-PVD thermal barrier coatings on tube superalloy substrate

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中国有色金属学会会刊：英文版 2006年第A02期16卷 10-13页

作者： GAO yu zhang Chun-xia zhou Chun-gen GONG Sheng-kai XU Hui-bin Department of Materials Science and Engineering B eijing University of Aeronautics and Astronautics Beijing 100083 China

Two-layer structured thermal barrier coatings (TBCs) (NiCoCrAlY (bond coat)+(6%-8%, mass fraction) Y2O3-stabilized ZrO2(YSZ top coat)) were deposited by electron beam physical vapor deposition (EB-PVD) on tube superalloy substrates. The samples were investigated by isothermal oxidation and thermal shock tests. It is found that the mass gains of the,substrate with and 2 without TBCs are 0.165 and 7.34 mg/cm(2), respectively. So the TBCs system is a suitable protection for the substrate. In thermal shock tests the vertical cracks initiate at the top coat and grow into the bond coat, causing the oxidation of the bond coat along the cracks. Failure of the TBCs system occurs by the spallation of the YSZ from the bond coat, and some micro-cracks are found at the location where the fragment of the YSZ top coat spalled from.

关键词：超耐热合金管状基质 EB-PVD 电子束物理汽相淀积氧化热冲击热障涂层热疲劳

Textured and toughened high-entropy(Ti_(0.2)Zr_(0.2)Hf_(0.2)Nb_(0.2)Ta_(0.2))C-SiCw ceramics

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Journal of Materials Science & Technology 2021年第35期94卷 99-103页

作者： Si-Chun Luo Wei-Ming Guo yu-zhang zhou Kevin Plucknett Hua-Tay Lin School of Electromechanical Engineering Guangdong University of TechnologyGuangzhou 510006China College of Mechanical and Electronic Engineering Pingxiang UniversityPingxiang337000China Department of Process Engineering and Applied Science Dalhousie UniversityHalifax B3J 1Z1Canada

High-entropy(Ti_(0.2)Zr_(0.2)Hf_(0.2)Nb_(0.2)Ta_(0.2))C ceramics,with different contents(0,5,10,and 20 vol.%)of Si C whiskers(SiCw),were fabricated by spark plasma sintering using raw powders synthesized via carbothermal *** application of a uniaxial compaction force led to texture development of the SiCw within the(Ti_(0.2)Zr_(0.2)Hf_(0.2)Nb_(0.2)Ta_(0.2))C *** toughness increased with the increase in SiCw content,while Vickers hardness remains almost *** toughness of(Ti_(0.2)Zr_(0.2)Hf_(0.2)Nb_(0.2)Ta_(0.2))C-20 vol.%SiCw ceramics reached 4.3±0.3 MPa m^(1/2),which was approximately 43%higher than that of the monolithic(Ti_(0.2)Zr_(0.2)Hf_(0.2)Nb_(0.2)Ta_(0.2))C ceramic(3.0±0.2 MPa m1/2).The main toughening mechanisms were attributed to crack deflection,whisker debonding,and whisker pullout.

关键词： High-entropy carbide ceramics Silican carbide whiskers Microstructure Mechanical properties Toughening mechanism

Co/Co_(7)Fe_(3)heterostructures with controllable alloying degree on carbon spheres as bifunctional electrocatalyst forrechargeable zinc-air batteries

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International Journal of Minerals,Metallurgy and Materials 2025年第2期32卷 476-487页

作者： Junkang Chen Yongyue Zhuang Yanxin Qiao yu zhang Aihua yuan Hu zhou School of Materials Science and Engineering Jiangsu University of Science and TechnologyZhenjiang 212003China School of Environmental and Chemical Engineering Jiangsu University of Science and TechnologyZhenjiang 212003China

Exploring efficient and nonprecious metal electrocatalysts of oxygen reduction reaction(ORR)and oxygen evolution reaction(OER)is crucial for developing rechargeable zinc-air batteries(ZABs).Herein,an alloying-degree control strategy was employed to fabricate nitrogen-doped carbon sphere(NCS)decorated with dual-phase Co/Co_(7)Fe_(3)heterojunctions(CoFe@NCS).The phase composition of materials has been adjusted by controlling the alloying *** optimal CoFe_(0.08)@NCS electrocatalyst displays a half-wave potential of 0.80 V for ORR and an overpotential of 283 mV at 10 mA·cm^(-2)for OER in an alkaline *** intriguing bifunctional electrocatalytic activity and durability is attributed to the hierarchically porous structure and interfacial electron coupling of highly-active Co_(7)Fe_(3)alloy and metallic Co *** the CoFe_(0.08)@NCS material is used as air-cathode catalyst of rechargeable liquid-state zinc-air battery(ZAB),the device shows a high peak power-density(157 mW·cm^(-2))and maintains a stable voltage gap over 150 h,outperforming those of the benchmark(Pt/C+RuO_(2))-based *** particular,the as-fabricated solid-state flexible ZAB delivers a reliable compatibility under different bending *** work provides a promising strategy to develop metal/alloy-based electrocatalysts for the application in renewable energy conversion technologies.

关键词： bifunctional electrocatalysts oxygen reduction reaction oxygen evolution reaction zinc-air battery metal/alloy carbon sphere

LABORATORY STUDIES ON WAVE FORCE OF COASTAL STRUCTURES MADE OF FLAT GEOTUBES

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Journal of Hydrodynamics 2011年第6期23卷 820-825页

作者： LIN Gang SHU Yi-ming LU Xin DAI Lin-jun yu Xin-zhou zhang Xian-lei YI Jing-rong College of Water Conservancy and Hydropower Engineering Hohai University Nanjing 210098 China

Flat geotubes are widely used for coastal structures such as seawalls, breakwaters and sightseeing groins, etc.. However, the understanding of the stable mechanism involved in the wave-structure interactions should be deepened, and one of the important work is to clarify the stress state of the structure under the wave action. In this article, wave force acting on coastal structures made of flat geotube is experimentally investigated. The required drag, inertia and lift coefficients are especially analyzed from the results of hydraulic model experiments specially designed for geotube structure. Several types of structures made of flat geotubes under wave action have been tested in order to understand the stress state of the geotube fixed to force transducer within different structures. Experimental results show that the wave-induced forces on the instrumented geotube are markedly influenced by wave elements. Meanwhile, the magnitude of horizontal force of adjoining geotube is different at the same time.

关键词： flat geotube wave force coefficients inertial force drag lift coastal structure hydraulic model experiment

Comparison of the effect of ranibizumab in retinal vein occlusion and macular edema with different optical coherence tomographic patterns

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International Journal of Ophthalmology(English edition) 2025年第2期18卷 275-282页

作者： yue Xu yue-Cong Yin Ze-yu Song Xiao-yu zhou Jia-Ju zhang Juan Liang Department of Ophthalmology the Fourth Affiliated Hospital of Soochow UniversitySuzhou 215000Jiangsu ProvinceChina

AIM:To explore the morphological and functional parameters to evaluate the effectiveness of intravitreal injections of ranibizumab(IVR)in treating macular edema(ME)secondary to retinal vein occlusion(RVO).METHODS:This retrospective study involved 65 RVO patients(65 eyes)who received IVR and were followedup for more than *** was categorized into cystoid macular edema(CME),diffuse retinal thickening(DRT),and serous retinal detachment(SRD)according to optical coherence tomography(OCT)*** comparison of best corrected visual acuity(BCVA;logMAR)and central macular thickness(CMT)among different follow-up points and those among 3 groups were performed by Kruskal-Wallis *** correlation between BCVA and baseline parameters during treatment was analyzed using Spearman correlation ***:BCVA tended to improve in all groups,with marked improvement in CME and DRT *** showed the greatest reduction after 1wk,and remained stable over the following *** patients had the worst BCVA and the highest CMT at baseline,but the differences became smaller after IVR *** in SRD group was significantly better than in CME and DRT groups 3mo after *** patients of CME and SRD groups transitioned to a normal pattern at 3mo *** patients were most likely to transform into the other morphological groups,while SRD patients showed minimal *** at baseline was identified as the most important prognostic indicator in all 3 ***,DRT patients with a longer clinical course,higher CMT and central retinal vein occlusion(CRVO)tend to exhibit worse BCVA after *** addition,CRVO patients are more likely to have worse BCVA at 2 and 3mo follow-up compared with branch retinal vein occlusion(BRVO)patients in CME *** patients with higher baseline CMT were prone to experiencing worse BCVA after ***:The effectiveness of IVR is strongly correlated with baseline BCVA in all 3 *** parameters inc

关键词： retinal vein occlusion optical coherence tomography serous retinal detachment cystoid macular edema diffuse retinal thickening

Ab　initio　Studies　on　Boron　Clusters　and　Their　Corresponding　Boranes　with　T_d,O_h　and　I_h　Symmetries

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Chemical Research in Chinese Universities 1997年第1期13卷 46-50页

作者： yu Wei zhou, zhang Ming yu and SUN Chia chung (Institute of Theoretical Chemistry, Jilin University, Changchun, 130023) JILIN UNIV INST THEORET CHEMCHANGCHUN 130023PEOPLES R CHINA

The thermal stability and bonding characteristics of the larger boron clusters B n and their corresponding boranes with T d , O h or I h symmetries were studied by means of ab initio... 详细信息

The thermal stability and bonding characteristics of the larger boron clusters B n and their corresponding boranes with T d , O h or I h symmetries were studied by means of ab initio method. The results obtained from the calculation show that the clusters and boranes are all thermally stable to a different extent. The number of the skeletal bonding orbitals of B n H 2- n satisfies the Wades rule, but this kind of clusters need not be a complete triangular face polyhedron. The results also indicate that the larger neutral boranes B n H n may exist.

关键词： Boron cluster Thermal stability Electron deficient property