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| 1 | Microstructure and shear strength of the brazed joint of Ti(C,N)-based cermet to steel显示文摘Firm joins were obtained between Ti(C,N)-based cermet and steel with Ag-Cu-Zn-Ni filler metal by vacuum brazing. The effects of technological parameters such as brazing temperature, holding time, and filler thickness on the shear strength of the joints were investigated. The microstructure of welded area and the reaction products of the filler metal were examined by scanning electron microscopy (SEM), metallographic microscope (OM), energy-dispersive X-ray analysis (EDS), and X-ray diffraction (XRD). The brazing temperature of 870°C, holding time of 15 min, and filler thickness of 0.4 mm are a set of optimum technological parameters, under which the maximum shear strength of the joints, 176.5 MPa, is achieved. The results of microstructure show that the wettability of the filler metal on Ti(C,N)-based cermet and steel is well. A mutual solution layer and a diffusion layer exist between the welding base materials and the filler metal. | YE Dameng, XIONG Weihao, Zhang Xiuhai, QU Jun, and YAO Zhenghua State Key Laboratory of Plastic Forming Simulation and Die & Mould Technology, Huazhong University of Science and Technology, Wuhan 430074, China | 2010 | Rare Metals2010，29，1： | 7 |
| 2 | Mutation analyses of integrated HBV genome in hepatitis B patients显示文摘Little has been learnt in the last 30 years about detection of HBV genome as well as its mutation analysis between hepatitis B fathers (HBF) and their children. In this study, we used nest polymerase chain reaction (PCR), fluorescence in situ hybridization (FISH), and DNA sequencing analysis, to examine the integrated HBV genome in paraffin-embedded testis tissues, which were taken as samples from HBF, and in peripheral blood mononuclear cells (PBMC) from 74 cases of HBFs and their children who were born after their fathers’ HBV infection (caHBF). We found that HBV DNA existed in testis tissues, mainly in the basilar parts of the seminiferous tubules, and also in PBMC of HBF. It was also documented that there were point mutations of poly-loci, insertions and deletions of nucleotides in integrated HBV genomes, and the types of gene mutations in the HBFs were similar to those in caHBF. This study addresses the major types of gene mutations in integrated HBV genome in human patients and also presents reliable evidence of possible genetic transmission of hepatitis B. | Peilin Wang Xiuhai Wang Shuying Cong Hongming Ma Xuecheng Zhang | 2008 | Journal of Genetics and Genomics2008，35，2： | 6 |
| 3 | Effect of bonding process on the properties of isotropic epoxy resin-bonded Nd-Fe-B magnets显示文摘Bonded NdFeB magnets were prepared by compression molding. The effect of preparation technology on their magnetic and mechanical properties was studied through the analysis of density, Br, Hcj, (BH)max, bending strength, and compressive strength of the bonded magnets. The results showed that the magnetic properties decreased with increasing binder content, whereas the mechanical properties increased. Br and (BH)max increased with rising pressure, whereas Hcj decreased. For a fixed mass fraction of the binder, the optimal pressure was 620 MPa and the best thermosetting temperature was 160°C. These conditions made the bonded magnets have the optimal mechanical properties. Scanning electron microscopy (SEM) analyses of the fracture surfaces indicated that the epoxy resin bonded magnets exhibited brittle behavior. | ZHANG Xiuhai XIONG Weihao | 2009 | Rare Metals2009，28，3： | 3 |
| 4 | Evaluating alternative hypotheses behind biodiversity and multifunctionality relationships in the forests of Northeastern China显示文摘Background:The importance of biodiversity in maintaining multiple ecosystem functions has been widely accepted.However,the specific mechanisms affecting biodiversity and ecosystem multifunctionality(BEMF)relationships in forests are largely unknown.This is particularly evident for the macroscale of a large forested landscape.Methods:Based on 412 one-tenth hectare field plots distributed over forested areas across northeastern China,we evaluated three alternative hypotheses explaining the relationships between BEMF,namely:niche complementarity,mass ratio,and vegetation quantity effect.We used Rao's quadratic entropy and community weighted mean trait values to quantify forest“biodiversity”.These two variables represent two complementary aspects of functional properties,which are in line with niche complementary and mass ratio effects,respectively.Results:Ecosystem multifunctionality was negatively associated with the community weighted mean values of acquisitive traits(a proxy of mass ratio effect).Rao's quadratic entropy(a proxy of niche complementarity)had no relationship with ecosystem multifunctionality.Higher stand biomass greatly increased ecosystem multifunctionality,which is in line with the vegetation quantity effect.Our results confirm that in the temperate forests of northeastern China,the relationship of BEMF was primarily affected by vegetation quantity,followed by mass ratio effects.Conclusions:The results of this study contribute to a better understanding of the main drivers of ecosystem multifunctionality in forest ecosystems.The results of this study provide additional evidence to support the vegetation quantity and mass ratio hypotheses in forest ecosystems. | Qingmin Yue Minhui Hao Yan Geng Xuerui Wang Klaus von Gadow Chunyu Zhang Xiuhai Zhao Lushuang Gao | 2022 | Forest Ecosystems2022，9，3： | 1 |
| 5 | Seed dispersal and seedling recruitment of trees at different successional stages in a temperate forest in northeastern China显示文摘spatial distribution of adult trees in a forest community is determined by patterns of both seed dispersal and seedling recruitment.the objectives of our study were to understand the processes of seed dispersal and seedling recruitment of dominant tree species in a temperate forest of northeastern China and to identify the factors constraining seed dispersal and seedling establishment at different stages of forest succession.Methods During three summer and autumn sessions between 2006 and 2008,altogether 113080 seeds from 22 different tree species were collected in three large field plots representing different for-est types in the Changbai mountain region of northeastern China.the spatial distribution of seed abundance was analyzed using a syrjala test.regeneration success of nine major tree species was assessed using variables defining‘limitations’in‘seeds’and‘seed-ling establishment’.Important Findings We found that seed production fluctuated between years and varied greatly with forest types.Four tree species,Acer spp.,Fraxinus man-dshurica,Tilia amurensis and Betula spp.,had the greatest seed pro-duction and the widest range of seed dispersal,whereas Quercus mongolica showed the most sustained seed production pattern.the spatial patterns of seed abundance differed significantly among forest types and years.the tree species investigated in this study differed in the degree of seed limitation,as well as in limitation of seedling establishment.there were both negative and positive correlations between seed density and seedling density,depending on site and parental tree density.seeds of 16 tree species were found in the Populus davidiana-Betula platyphylla forest(PbF)plot,11 in the conifer and broad-leaved mixed forest(CbF)plot but only 8 in the broad-leaved-Korean pine mixed forest(bKF)plot.the number of seed-contributing species was not only greater in the secondary forests(CbF and PbF plots)than in the primary forest(bKF plot)but was also more variable during the 3 years of assessment.results from the correlations between seed density and seedling occurrence and that between parental tree density or seed weight and dispersal limitation confirm our intuitive expectations,i.e.heavy seeds had greater dispersal limitation but higher establishment success than light seeds. | Lie Chen Lei Wang Yeerjiang Baiketuerhan Chunyu Zhang Xiuhai Zhao Klaus von Gadow | 2014 | Journal of Plant Ecology2014，7，4： | 1 |
| 6 | Cloning and characterization of maize ZmSPK1, a homologue to nonfermentingl-related protein kinase2 显示文摘 | Zou Huawein Zhang Xiuhai Zhao Jiuran | 2006 | African Journal of Biotechnology2006，5，： | 1 |
| 7 | Structural diversity of forest communities on Baihuashan Mountain, Beijing显示文摘 | Jingming Zheng Xiuhai Zhao Chunyu Zhang | 2008 | Frontiers of Forestry in China2008，，2： | 1 |
| 8 | Nucleic acids analysis显示文摘Nucleic acids are natural biopolymers of nucleotides that store, encode, transmit and express genetic information, which play central roles in diverse cellular events and diseases in living things. The analysis of nucleic acids and nucleic acids-based analysis have been widely applied in biological studies, clinical diagnosis, environmental analysis, food safety and forensic analysis.During the past decades, the field of nucleic acids analysis has been rapidly advancing with many technological breakthroughs.In this review, we focus on the methods developed for analyzing nucleic acids, nucleic acids-based analysis, device for nucleic acids analysis, and applications of nucleic acids analysis. The representative strategies for the development of new nucleic acids analysis in this field are summarized, and key advantages and possible limitations are discussed. Finally, a brief perspective on existing challenges and further research development is provided. | Yongxi Zhao Xiaolei Zuo Qian Li Feng Chen Yan-Ru Chen Jinqi Deng Da Han Changlong Hao Fujian Huang Yanyi Huang Guoliang Ke Hua Kuang Fan Li Jiang Li Min Li Na Li Zhenyu Lin Dingbin Liu Juewen Liu Libing Liu Xiaoguo Liu Chunhua Lu Fang Luo Xiuhai Mao Jiashu Sun Bo Tang Fei Wang Jianbin Wang Lihua Wang Shu Wang Lingling Wu Zai-Sheng Wu Fan Xia Chuanlai Xu Yang Yang Bi-Feng Yuan Quan Yuan Chao Zhang Zhi Zhu Chaoyong Yang Xiao-Bing Zhang Huanghao Yang Weihong Tan Chunhai Fan | 2021 | Science China Chemistry2021，64，2： | 1 |
| 9 | Effect of Preparations of Bamboo Vinegar and Copper Sulfate on Green Algae and Tobacco Seedling Growth显示文摘To provide theoretical and technical basis for the application of preparations of bamboo vinegar and copper sulfate in the prevention of green algae in floating system for tobacco seeding,the soaking and spraying methods were employed to study the effect of different concentrations of preparations of bamboo vinegar and copper sulfate on green algae and tobacco seedling growth. The results showed that the preparations of bamboo vinegar and copper sulfate of different concentrations played a strong role in inhibiting green algae growth and had better effect than copper sulfate. Spraying 1∶ 200 preparations of bamboo vinegar and copper sulfate could significantly promote tobacco seedling growth,and the leaf fresh weight increased by 15. 80% compared with CK,with significant difference; spraying 1∶ 50 preparations was not conducive to tobacco seedling growth. It was recommended to spray 1∶ 200 preparations of bamboo vinegar and copper sulfate in floating system for tobacco seeding,which could promote tobacco seedling growth and reduce green algae to varying degrees. | Tingqing WANG Lingjie XU Qianhua YUAN Xiuhai ZHANG Weiqian ZHONG Kun QIU Chuanren MA | 2017 | Asian Agricultural Research2017，9，6： | 1 |
| 10 | Development and Application of an in Situ Penetrator for Rapid Strength Testing of Submarine Sediment显示文摘In marine engineering, the strength of a submarine sediment is an indispensable parameter for assessment of construction. In this study, a free-fall cone penetrator named IPen was developed to realize a rapid and efficient measurement of sediment strength. The equipment is characterized by modular design and self-contained data acquisition. It is equipped with an acceleration sensor, a water pressure sensor, and a piezocone penetration test(CPTu) probe. It is designed to be released from near seabed surface with a releaser and then fall freely to provide a higher penetration velocity. Its maximum working depth is approximately 2500 m and maximum penetration depth is approximately 3 m. To derive the correlation between penetration resistance and sediment strength, a calibrator was devised to determine the penetration-rate factor. In addition, the factor applicable to in situ test points was determined in laboratory experiments. In June 2016, the IPen was tested in situ in the South Yellow Sea, China, during a shared voyage funded by the National Science Foundation. Meanwhile, undisturbed column samples were collected for laboratory tests. Based on the in situ test results, it was demonstrated that the IPen could accurately record the working states of various sensors during the freely falling course. IPen test results reliably reflected the sediment strength at all the testing points when compared with laboratory calibration tests, in situ vane tests and penetration tests, laboratory penetration tests, and unconsolidated and undrained triaxial compression tests. | ZHANG Minsheng WANG Zhenhao WANG Xiuhai WEN Mingzheng HONG Bo | 2019 | Journal of Ocean University of China2019，18，2： | 1 |
| 11 | Research of warm compaction technology on nylon bonded Nd-Fe-B magnets显示文摘Warm compaction and room temperature compaction were applied to prepare bonded Nd-Fe-B magnets. The results indicated that the density of magnet was determined by the compaction pressure and warm compaction temperature, whereas, the thermosetting temperature could hardly affect the density of magnet. The mechanical properties of magnets were the best when the thermosetting temperature was 200 ℃. The Br, Hcb, and (BH)max of warm compaction magnet were higher than those of room compaction. When the warm compaction temperature and thermosetting temperature were invariable, the density of magnet increased with the increase of compaction pressure, which resulted in the increase of Br, Hcb, and (BH)max of magnet and the decrease of Hcj of magnet. When the warm compaction temperature and compaction pressure were invariable, the magnetic properties of magnets decreased with the increase of thermosetting temperature. The magnetic properties of warm compaction molding magnets were better than those of injection molding magnets. | Xiuhai ZHANG Weihao XIONG Dameng YE Jun QU Zhenhua YAO | 2009 | Acta Metallurgica Sinica(English Letters)2009，22，3： | 1 |
| 12 | Research on Corrosion Effect of Sulfate Ions on Concrete Under Wetting-Drying Cycle显示文摘Saline soil is widely distributed in the marine sediments along the coast of the world and the arid-semi-arid areas of the Middle East and Iraq,and calcium sulfate erosion has become one of the important factors affecting the durability of concrete in this area.In order to clarify the mechanism of sulfate ion damage to concrete,this paper mainly takes saline soil with high sulfate content in coastal area as well as arid-semi-arid area as the research object,and uses indoor geotechnical test,field test and numerical simulation to study the influence of different dry-wet cycle times on the unconfined compressive strength of concrete test blocks,and puts forward the relationship between the erosion arrival depth and time of sulfate ion in concrete,so as to predict the long-term erosion depth by using the erosion depth of sulfate ion in concrete in short time.The results show that the shorter the erosion time when the erosion reaches a certain depth,and the larger the erosion reaches when the erosion time is the same,the faster the erosion reaches the depth with the increase of erosion time.Compared with rectangular section concrete,circular section concrete penetrates faster.The results of this study can provide a reference for the durability design of concrete in saline soil sites containing sulfate. | WANG Xiuhai TIAN Zhuangcai ZHANG Yanan SU Xiuting LIU Hongjun LIU Tao | 2022 | Journal of Ocean University of China2022，21，1： | 0 |
| 13 | Drivers of tree demographic trade-offs in a temperate forest显示文摘Background: The demographic trade-offs(i.e. growth and survival) play important roles in forest dynamics and they are driven by multiple factors, including species’ inherent life-history strategies(such as shade-tolerance and mycorrhizal type), neighborhood interactions(such as conspecific negative density dependence, CNDD), and abiotic environment pressures. Although studies found that CNDD occurred in tropical and temperate forest,attempts to identify how the variations in CNDD control their impacts on growth and survival remain debate. In the present study, we conducted an extensive field survey, and analyzed demographic rates from 24 co-occurring temperate tree species, in order to test the importance of CNDD in shaping the growth-survival trade-offs.Results: Our study found that density dependence and environmental filtering were strong predictors for individual growth-survival trade-offs, while they showed variations across shade-intolerant and ectomycorrhizal species, as well as saplings and juveniles with more negative CNDD. Species growth showed positive relationship with mortality. And our results also support the fact that CNDD drives species growth-survival trade-offs at the community level with environmental stress.Conclusions: Our study indicates that biotic interactions such as density dependence and environment filtering played an important role in growth-survival trade-offs, and confirmed that the Janzen-Connell hypothesis in temperate forest was associated with species life-history strategies. In addition, shade-tolerance, mycorrhizal type and life-stage of forest species responded differently to CNDD, thus providing insights regarding different community assembly mechanisms and their interactions. Therefore, it is important to take species survival with growth and species life-history strategies into account when focusing on forest dynamics. | Jianghuan Qin Chunyu Fan Yan Geng Chunyu Zhang Xiuhai Zhao Lushuang Gao | 2022 | Forest Ecosystems2022，9，4： | 0 |
| 14 | Cross-classes domain inference with network sampling for natural resource inventory显示文摘There are two distinct types of domains,design-and cross-classes domains,with the former extensively studied under the topic of small-area estimation.In natural resource inventory,however,most classes listed in the condition tables of national inventory programs are characterized as cross-classes domains,such as vegetation type,productivity class,and age class.To date,challenges remain active for inventorying cross-classes domains because these domains are usually of unknown sampling frame and spatial distribution with the result that inference relies on population-level as opposed to domain-level sampling.Multiple challenges are noteworthy:(1)efficient sampling strategies are difficult to develop because of little priori information about the target domain;(2)domain inference relies on a sample designed for the population,so within-domain sample sizes could be too small to support a precise estimation;and(3)increasing sample size for the population does not ensure an increase to the domain,so actual sample size for a target domain remains highly uncertain,particularly for small domains.In this paper,we introduce a design-based generalized systematic adaptive cluster sampling(GSACS)for inventorying cross-classes domains.Design-unbiased Hansen-Hurwitz and Horvitz-Thompson estimators are derived for domain totals and compared within GSACS and with systematic sampling(SYS).Comprehensive Monte Carlo simulations show that(1)GSACS Hansen-Hurwitz and Horvitz-Thompson estimators are unbiased and equally efficient,whereas thelatter outperforms the former for supporting a sample of size one;(2)SYS is a special case of GSACS while the latter outperforms the former in terms of increased efficiency and reduced intensity;(3)GSACS Horvitz-Thompson variance estimator is design-unbiased for a single SYS sample;and(4)rules-ofthumb summarized with respect to sampling design and spatial effect improve precision.Because inventorying a mini domain is analogous to inventorying a rare variable,alternative network sampling procedures are also readily available for inventorying cross-classes domains. | Zhengyang Hou Ronald E.McRoberts Chunyu Zhang Göran Ståhl Xiuhai Zhao Xuejun Wang Bo Li Qing Xu | 2022 | Forest Ecosystems2022，9，3： | 0 |
| 15 | Forest observational studies-an essential infrastructure for sustainable use of natural resources显示文摘This contribution complements Forest Ecosystems' Thematic Series on 'Forest Observational Studies'.We provide essential clarification regarding the definition and purpose of long-term field studies,review some of the extensive literature and discuss different approaches to collecting field data.We also describe two newly established forest observational networks that serve to illustrate the scope and diversity of forest field studies.The first is a large-scale network of forest observational studies in prominent natural forest ecosystems in China.The second example demonstrates observational studies in mixed and uneven-aged pine-oak forests which are selectively managed by local communities in Mexico.We summarize the potential for analysing and modeling forest ecosystems within interdisciplinary projects and provide argumentation in favour of long-term institutional commitment to maintaining forest observational field studies. | XiuHai Zhao Javier Corral-Rivas ChunYu Zhang Hailemariam Temesgen Klaus v Gadow | 2014 | Forestry Studies in China2014，16，2： | 0 |
| 16 | Mismatch between species distribution and climatic niche optima in relation to functional traits显示文摘Background:Forecasts of climate change impacts on biodiversity often assume that the current geographical distributions of species match their niche optima.However,empirical evidence has challenged this assumption,suggesting a mismatch.We examine whether the mismatch is related to functional traits along temperature or precipitation gradients.Methods:The observed distributions of 32 tree species in northeast China were evaluated to test this mismatch.Bayesian models were used to estimate the climatic niche optima,i.e.the habitats where the highest species growth and density can be expected.The mismatch is defined as the difference between the actual species occurrence in an assumed niche optimum and the habitat with the highest probability of species occurrence.Species’functional traits were used to explore the mechanisms that may have caused the mismatches.Results:Contrasting these climatic niche optima with the observed species distributions,we found that the distribution-niche optima mismatch had high variability among species based on temperature and precipitation gradients.However,these mismatches depended on functional traits associated with competition and migration lags only in temperature gradients.Conclusions:We conclude that more relevant research is needed in the future to quantify the mismatch between species distribution and climatic niche optima,which may be crucial for future designs of forested landscapes,species conservation and dynamic forecasting of biodiversity under expected climate change. | Zhenghua Lian Juan Wang Chunyu Zhang Xiuhai Zhao Klaus von Gadow | 2022 | Forest Ecosystems2022，9，6： | 0 |
| 17 | Laser-Derived Interfacial Confinement Enables Planar Growth of 2D SnS_(2) on Graphene for High-Flux Electron/Ion Bridging in Sodium Storage显示文摘Establishing covalent heterointerfaces with face-to-face contact is promising for advanced energy storage,while challenge remains on how to inhibit the anisotropic growth of nucleated crystals on the matrix.Herein,faceto-face covalent bridging in-between the 2 D-nanosheets/graphene heterostructure is constructed by intentionally prebonding of laser-manufactured amorphous and metastable nanoparticles on graphene,where the amorphous nanoparticles were designed via the competitive oxidation of Sn-O and Sn-S bonds,and metastable feature was employed to facilitate the formation of the C-S-Sn covalent bonding in-between the heterostructure.The face-to-face bridging of ultrathin SnS;nanosheets on graphene enables the heterostructure huge covalent coupling area and high loading and thus renders unimpeded electron/ion transfer pathways and indestructible electrode structure,and impressive reversible capacity and rate capability for sodium-ion batteries,which rank among the top in records of the SnS_(2)-based anodes.Present work thus provides an alternative of constructing heterostructures with planar interfaces for electrochemical energy storage and even beyond. | Xiaosa Xu Fei Xu Xiuhai Zhang Changzhen Qu Jinbo Zhang Yuqian Qiu Rong Zhuang Hongqiang Wang | 2022 | Nano-Micro Letters2022，14，6： | 0 |
| 18 | Impact of seepage flow on sediment resuspension by internal solitary waves:parameterization and mechanism显示文摘Sediment incipient motion is the first step in sediment resuspension.Previous studies ignored the effect of seepage flow on the mobility of sediment particles and simplified the seabed surface as a rigid boundary.A flume experiment was designed to innovatively divide the seabed into two parts to control the dynamic response of the seabed and control the seepage conditions.In the experiment,the seabed sediments and the amplitude of internal solitary waves(ISWs)were changed to compare and analyze the impact of seepage flow on the sediment resuspension by shoaling ISWs.Moreover,parametric research and verification were carried out.Results indicate that seepage flow can greatly influence fine sand,promote sediment resuspension,and increase the amount of suspension by two times on average.However,seepage flow had a little effect on the suspension of clayey silt and sandy silt.Besides,seepage force was added to the traditional gravity,drag force,and uplift force,and the parameterization of threshold starting shear stress of coarse-grained sediments was developed.The results of this parameterization were verified,and seepage force was critical to parameterization.The threshold starting shear stress was reduced by 54.6%after increasing the seepage force.The physical mechanism of this process corresponded to the vertical reciprocating transient seepage in and out the seabed interface caused by the wave-induced transient excess pore water pressure.This quantitative study on seepage flow for shear stress of coarse-grained sediments induced by ISWs is critical to geohazard assessment. | Zhuangcai TIAN Chao LIU Ziyin REN Xiujun GUO Mingwei ZHANG Xiuhai WANG Lei SONG Yonggang JIA | 2023 | Journal of Oceanology and Limnology2023，41，2： | 0 |
| 19 | N-Heterocyclic carbene-catalyzed enantioselective(dynamic) kinetic resolutions and desymmetrizations显示文摘N-heterocyclic carbene-catalyzed enantioselective kinetic resolutions,dynamic kinetic resolutions,and desymmetrization reactions are systematically reviewed.The content is organized according to the activation modes involved in these transformations.Future advances within this highly active research field are discussed from our perspectives on the topic. | Yi Zhang Hui Cai Xiuhai Gan Zhichao Jin | 2024 | Science China Chemistry2024，67，2： | 0 |
| 20 | Simulation of the Impact of Breakwaters on Hydrodynamic Environment in Laizhou Bay, China显示文摘The construction of two sand breakwaters in Guangli Port might cause changes to the marine environment of Laizhou Bay.Tidal flow field and conservative substance transport are simulated by a two-dimensional hydrodynamic model MIKE21 to assess the impact of breakwaters on the hydrodynamic environment.The results show that the construction has minor influences on the tidal currents.The changes mainly occur in the region near the port(about 20 km^(2) in area).The directions of currents during flood tide and ebb tide veer less than 20 degrees,and a maximum change in speed of(0.87±0.1)m s^(−1) occurs in between the breakwaters during ebb tide.However,the self-purification ability of Laizhou Bay is significantly reduced according to the conservative substance transport model,especially in the southwest(about 100 km from the Guangli Port to the estuary of Xiaoqinghe River),where the water exchange rate decreases by 10%–20%.The breakwaters slow down the northward current during ebb tide,which causes the accumulation of pollutants. | HU Kaiyu ZHANG Wei WANG Xiuhai | 2022 | Journal of Ocean University of China2022，21，6： | 0 |
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