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Identification of novel mammalian viruses in tree shrews(Tupaia belangeri chinensis)
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作者 Hong Zhou Ren-Rong Tian +9 位作者 Xiu-Rong Wang Jin-Xuan Yang Yun-Xiao Wang Ming-Liang Zhao xu-dong zhang Yu-Hua Ma Long-Bao Lv Edward CHolmes Yong-Tang Zheng Wei-Feng Shi 《Zoological Research》 SCIE CSCD 2024年第2期429-438,共10页
The Chinese tree shrew(Tupaia belangeri chinensis),a member of the mammalian order Scandentia,exhibits considerable similarities with primates,including humans,in aspects of its nervous,immune,and metabolic systems.Th... The Chinese tree shrew(Tupaia belangeri chinensis),a member of the mammalian order Scandentia,exhibits considerable similarities with primates,including humans,in aspects of its nervous,immune,and metabolic systems.These similarities have established the tree shrew as a promising experimental model for biomedical research on cancer,infectious diseases,metabolic disorders,and mental health conditions.Herein,we used metatranscriptomic sequencing to analyze plasma,as well as oral and anal swab samples,from 105 healthy asymptomatic tree shrews to identify the presence of potential zoonotic viruses.In total,eight mammalian viruses with complete genomes were identified,belonging to six viral families,including Flaviviridae,Hepeviridae,Parvovirinae,Picornaviridae,Sedoreoviridae,and Spinareoviridae.Notably,the presence of rotavirus was recorded in tree shrews for the first time.Three viruses-hepacivirus 1,parvovirus,and picornavirus-exhibited low genetic similarity(<70%)with previously reported viruses at the whole-genome scale,indicating novelty.Conversely,three other viruses-hepacivirus 2,hepatovirus A and hepevirus-exhibited high similarity(>94%)to known viral strains.Phylogenetic analyses also revealed that the rotavirus and mammalian orthoreovirus identified in this study may be novel reassortants.These findings provide insights into the diverse viral spectrum present in captive Chinese tree shrews,highlighting the necessity for further research into their potential for crossspecies transmission. 展开更多
关键词 Tree shrew(Tupaia belangeri chinensis) Meta-transcriptomic sequencing Mammalian viruses Genomic analysis
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Effects of cooling rate on microstructure and microhardness of directionally solidified Galvalume alloy
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作者 Ji-peng Li De-gao Qiao +4 位作者 Jian Li Xiao-yang Luo Peng Peng Xian-tao Yan xu-dong zhang 《China Foundry》 SCIE EI CAS CSCD 2024年第3期213-220,共8页
The influences of cooling rate on the phase constitution,microstructural length scale,and microhardness of directionally solidified Galvalume(Zn-55Al-1.6Si)alloy were investigated by directional solidification experim... The influences of cooling rate on the phase constitution,microstructural length scale,and microhardness of directionally solidified Galvalume(Zn-55Al-1.6Si)alloy were investigated by directional solidification experiments at different withdrawal speeds(5,10,20,50,100,200,and 400μm·s^(-1)).The results show that the microstructure of directionally solidified Galvalume alloys is composed of primary Al dendrites,Si-rich phase and(Zn-Al-Si)ternary eutectics at the withdrawal speed ranging from 5 to 400μm·s^(-1).As the withdrawal speed increases,the segregation of Si element intensifies,resulting in an increase in the area fraction of the Si-rich phase.In addition,the primary Al dendrites show significant refinement with an increase in the withdrawal speed.The relationship between the primary dendrite arm spacing(λ_(1))and the thermal parameters of solidification is obtained:λ_(1)=127.3V^(-0.31).Moreover,as the withdrawal speed increases from 5 to 400μm·s^(-1),the microhardness of the alloy increases from 90 HV to 151 HV.This is a combined effect of grain refinement and second-phase strengthening. 展开更多
关键词 Galvalume alloy directional solidification microstructure length scale MICROHARDNESS
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Midpoint transverse process to pleura block for postoperative analgesia following laparoscopic renal cyst decortication:Two case reports
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作者 Wei-Jie He Wen-Xing Xu +4 位作者 xu-dong zhang Yue Chen Shu-Ying He Xian-Qin Wei Xiao-Lan Huang 《World Journal of Clinical Cases》 SCIE 2024年第18期3629-3635,共7页
BACKGROUND The midpoint transverse process to pleura(MTP)block,a novel technique for thoracic paravertebral block(TPVB),was first employed in laparoscopic renal cyst decortication.CASE SUMMARY Thoracic paravertebral n... BACKGROUND The midpoint transverse process to pleura(MTP)block,a novel technique for thoracic paravertebral block(TPVB),was first employed in laparoscopic renal cyst decortication.CASE SUMMARY Thoracic paravertebral nerve block is frequently employed for perioperative analgesia during laparoscopic cyst decortication.To address safety concerns associated with TPVBs,we administered MTP blocks in two patients prior to administering general anesthesia for laparoscopic cyst decortication.The MTP block was performed at the T9 level under ultrasound guidance,with 20 mL of 0.5%ropivacaine injected.Reduced sensation to cold and pinprick was observed from the T8 to T11 dermatome levels.Immediately postoperative Numeric Pain Rating Scale scores were 0/10 at rest and on movement,with none exceeding a mean 24 h numeric rating scale>3.CONCLUSION MTP block was effective technique for providing postoperative analgesia for patients undergoing laparoscopic renal cyst decortication. 展开更多
关键词 Midpoint transverse process to pleura block Laparoscopic renal cyst decortication PAIN ANALGESIA Case report
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Synthesis of Ionic and Non-Ionic Modified Waterborne Polyurethane Curing Agent
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作者 Ying Qiao xu-dong zhang 《Journal of Electronic Research and Application》 2024年第1期86-92,共7页
By using HDI and TMP as the main raw materials,polyethylene glycol 400(PEG400)is used as a non-ionic hydrophilic modifier,and sodium hydroxyethyl sulfonate is used as an ionic hydrophilic modifier to synthesize a dual... By using HDI and TMP as the main raw materials,polyethylene glycol 400(PEG400)is used as a non-ionic hydrophilic modifier,and sodium hydroxyethyl sulfonate is used as an ionic hydrophilic modifier to synthesize a dual hydrophilic modified polyurethane curing agent.Research revealed that introducing PEG400 for hydrophilic chain segments and sodium hydroxyethyl sulfonate for hydrophilic ionic groups in the polyurethane curing agent component leads to a uniform distribution of hydrophilic components,significantly enhancing compatibility with the aqueous polyol component,and results in excellent film performance.The synthesis process and film were characterized using Fourier transform infrared spectroscopy and high-resolution scanning electron microscopy in the study. 展开更多
关键词 COATING Water polyurethane Curing agent Two-package Double modification
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IP Lyn:A Totally Eclipsing Contact Binary with an Extremely Low Mass Ratio
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作者 Zi-Xuan Yin Zi-Bin Meng +4 位作者 Pei-Ru Wu xu-dong zhang Yun-Xia Yu Ke Hu Fu-Yuan Xiang 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2023年第8期206-219,共14页
We present the first photometric and orbital period investigations for a neglected totally eclipsing contact binary IP Lyn.The photometric solutions derived from both ground-based and several surveys'observations ... We present the first photometric and orbital period investigations for a neglected totally eclipsing contact binary IP Lyn.The photometric solutions derived from both ground-based and several surveys'observations suggest that it is a shallow contact binary with an extremely low mass ratio of 0.055.The weak asymmetry observed in our multiple band light curves can be interpreted as a result of an active cool spot on the primary.The absolute physical parameters were determined with the Gaia-distance-based method and checked by an empirical relation.Combining the eclipse timings collected from the literature and those derived from our and variable surveys'observations,we find that IP Lyn has been undergoing a secular orbital period increase for the past two decades,implying a mass transfer from the less massive secondary to the primary.By comparing the current parameters with the critical instability ones,we infer that IP Lyn is currently stable in spite of its relatively low mass ratio and orbital angular momentum.Finally,from a catalog of 117 extremely low mass ratio contact binaries,we find that their orbital angular momenta are significantly lower than those of the contact binaries with a relatively high mass ratio,suggesting they should be at the late evolutionary stage of a contact binary. 展开更多
关键词 (stars")binaries(including multiple) close-(stars:)binaries eclipsing-stars evolution-stars individual(IP Lyn)
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Effect of Ta on solidification characteristics and mechanical properties of DZ411 Ni-based superalloy
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作者 Peng Peng Zi-jie Liu +3 位作者 Yuan-li Xu xu-dong zhang Zhi-kun Ma Jia-tai Wang 《China Foundry》 SCIE CAS CSCD 2023年第5期376-386,共11页
The effects of Ta content(2.72wt.%,3.10wt.%and 4.00wt.%)on the solidification characteristics and mechanical properties of directionally solidified DZ411 Ni-based superalloys were investigated.It is found that the con... The effects of Ta content(2.72wt.%,3.10wt.%and 4.00wt.%)on the solidification characteristics and mechanical properties of directionally solidified DZ411 Ni-based superalloys were investigated.It is found that the content of Mo decreases with the increase of Ta in liquid phase after directional solidification,indicating the addition of Ta can reduce the element segregation in alloys.The primary and secondary dendrite arm spacings(PDAS and SDAS)of the DZ411 alloy increase with the addition of Ta,which are consistent with the models by Hunt and Wagner.The increase of PDAS and SDAS can provide enough space for the growth of tertiary dendrite arms,which hinders the growth of unfavorably oriented primary dendrites.As a result,the addition of Ta facilitates the growth of favorably oriented dendrites.More MC carbides andγ-γ'eutectics are formed in the interdendritic regions,which is attributed to the segregation of Ta in the liquid phase.Furthermore,the degree of supersaturation of W,Mo inγmatrix increases with the increase of Ta,thus,the addition of Ta promotes the formation of TCP phase.The addition of Ta also increases the microhardness in both the primary dendrite and interdendritic regions of the alloy,and the microhardness of the primary dendrite is closer to that in interdendritic regions with the increase of Ta. 展开更多
关键词 DZ411 superalloy directional solidification TA dendrite arm spacing MICROHARDNESS
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Analysis on phase selection and microstructure evolution in directionally solidified Zn-Al-Mg-Ce alloy
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作者 Ji-peng Li De-gao Qiao +3 位作者 Shi-wen Dong Peng Peng Xian-tao Yan xu-dong zhang 《China Foundry》 SCIE CAS CSCD 2023年第4期347-355,共9页
In the process of hot-dip Zn-Al-Mg alloy coating,the plating solution dissipates heat in the direction perpendicular to the steel plate,which is considered to be a process of directional solidification.To understand t... In the process of hot-dip Zn-Al-Mg alloy coating,the plating solution dissipates heat in the direction perpendicular to the steel plate,which is considered to be a process of directional solidification.To understand the relationship between microstructure and cooling rate of Zn-Al-Mg alloys,both the phase constitution and microstructure characteristic length scales of Zn-9.5Al-3Mg-0.01Ce(wt.%)alloy were investigated by the directional solidification experiments at different growth velocities(V=40,80,160,250μm·s^(-1)).The experimental results show that the microstructure of directionally solidified Zn-9.5Al-3Mg-0.01Ce alloy is composed of primary Al dendrites and(Zn-Al-Mg2Zn11)ternary eutectics at the growth velocities ranging from 40 to 250μm·s^(-1).The primary Al dendrites are aligned regularly along the growth direction,accompanied with obvious secondary dendrites.The relationship between the microstructure length scale and the thermal parameters of solidification is obtained:λ1=374.66V-0.383,andλ2=167.5V-0.563(λ1is the primary dendrite arm spacing,andλ2 is the secondary dendrit arm spacing).In addition,through the interface response function(IRF)and the nucleation and constitutional undercooling(NCU),the phase selection of Zn-9.5Al-3Mg-0.01Ce is obtained:(Zn+Al+Mg2Zn11)ternary eutectics in the Zn-9.5Al-3Mg-0.01Ce alloy will be replaced by ternary eutectics(Zn+Al+MgZn2)when the growth rate is lower than 7.53μm·s^(-1). 展开更多
关键词 Zn-Al-Mg alloy directional solidification microstructure length scale phase selection
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Design,fabrication and optimization of electromagnetic absorption metamaterials
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作者 娄琦 张旭东 夏明岗 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第9期1-14,共14页
For decades,the rapid development of wireless communication has provided people a smarter way of living.However,a significant increase in electromagnetic pollution is an unavoidable consequence.Evading radar detection... For decades,the rapid development of wireless communication has provided people a smarter way of living.However,a significant increase in electromagnetic pollution is an unavoidable consequence.Evading radar detection in modern warfare has also become an important prerequisite for survival on the battlefield.This review provides a comprehensive overview of the current status and types of electromagnetic absorption metamaterials,especially their design and preparation methods.Moreover,this review focuses on the strategies used to optimize the absorber absorption performance.Finally,this review presents a viewpoint on future research on electromagnetic absorption metamaterials,the main challenges that need to be addressed and the possible solutions. 展开更多
关键词 METAMATERIAL electromagnetic wave absorption fractal design
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水热法制备镍掺杂ZnS纳米棒的显微组织与光催化性能(英文) 被引量:4
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作者 赵文华 魏智强 +3 位作者 武晓娟 张旭东 张莉 王璇 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2019年第1期157-164,共8页
采用水热法合成纯ZnS和Ni掺杂ZnS纳米棒。通过X射线衍射(XRD)、高分辨透射电子显微镜(HRTEM)、色散能量分析谱仪(EDS)和紫外可见吸收光谱(UV-Vis)等技术分别研究Ni掺杂对样品的物相结构、形貌、元素组成和光学性能的影响,并通过紫外光... 采用水热法合成纯ZnS和Ni掺杂ZnS纳米棒。通过X射线衍射(XRD)、高分辨透射电子显微镜(HRTEM)、色散能量分析谱仪(EDS)和紫外可见吸收光谱(UV-Vis)等技术分别研究Ni掺杂对样品的物相结构、形貌、元素组成和光学性能的影响,并通过紫外光照射在水溶液中降解有机染料罗丹明B(RhB)研究Zn_(1-x)Ni_xS纳米棒的光催化活性。结果表明:所有样品具有纤锌矿结构,结晶良好。样品的形貌均为一维纳米棒结构,分散性较好,晶格常数发生畸变。掺杂Zn_(1-x)Ni_xS的带隙小于纯ZnS的,因此,发生红移现象。Ni掺杂ZnS纳米材料能增强降解有机染料罗丹明B的光催化活性,尤其是Zn_(0.97)Ni_(0.03)S样品对罗丹明B具有较好的光催化性能和光催化稳定性。 展开更多
关键词 Zn1-xNixS纳米棒 物相结构 显微组织 光催化活性 水热法
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RIP3/MLKL-mediated neuronal necroptosis induced by methamphetamine at 39℃ 被引量:8
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作者 Li-Min Guo Zhen Wang +8 位作者 Shi-Ping Li Mi Wang Wei-Tao Yan Feng-Xia Liu Chu-Dong Wang xu-dong zhang Dan Chen Jie Yan Kun Xiong 《Neural Regeneration Research》 SCIE CAS CSCD 2020年第5期865-874,共10页
Methamphetamine is one of the most prevalent drugs abused in the world.Methamphetamine abusers usually present with hyperpyrexia (39℃),hallucination and other psychiatric symptoms.However,the detailed mechanism under... Methamphetamine is one of the most prevalent drugs abused in the world.Methamphetamine abusers usually present with hyperpyrexia (39℃),hallucination and other psychiatric symptoms.However,the detailed mechanism underlying its neurotoxic action remains elusive.This study investigated the effects of methamphetamine + 39℃ on primary cortical neurons from the cortex of embryonic Sprague-Dawley rats.Primary cortex neurons were exposed to 1 mM methamphetamine + 39℃.Propidium iodide staining and lactate dehydrogenase release detection showed that methamphetamine + 39℃ triggered obvious necrosis-like death in cultured primary cortical neurons,which could be partially inhibited by receptor-interacting protein-1 (RIP1) inhibitor Necrostatin-1 partially.Western blot assay results showed that there were increases in the expressions of receptor-interacting protein-3 (RIP3) and mixed lineage kinase domain-like protein (MLKL) in the primary cortical neurons treated with 1 mM methamphetamine + 39℃ for 3 hours.After pre-treatment with RIP3 inhibitor GSK’872,propidium iodide staining and lactate dehydrogenase release detection showed that neuronal necrosis rate was significantly decreased;RIP3 and MLKL protein expression significantly decreased.Immunohistochemistry staining results also showed that the expressions of RIP3 and MLKL were up-regulated in brain specimens from humans who had died of methamphetamine abuse.Taken together,the above results suggest that methamphetamine + 39℃ can induce RIP3/MLKL regulated necroptosis,thereby resulting in neurotoxicity.The study protocol was approved by the Medical Ethics Committee of the Third Xiangya Hospital of Central South University,China (approval numbers: 2017-S026 and 2017-S033) on March 7,2017. 展开更多
关键词 GSK'872 human brain tissue hyperpyrexia METHAMPHETAMINE mixed LINEAGE kinase domain-like protein necrostatin-1 NECROPTOSIS nerve REGENERATION neural REGENERATION rat CORTICAL neurons receptor-interacting protein-3 synergistic effect
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Numerical study on three-dimensional flow field of continuously rotating detonation in a toroidal chamber 被引量:4
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作者 xu-dong zhang Bao-Chun Fan +2 位作者 Ming-Yue Gui Zhen-Hua Pan Gang Dong 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2012年第1期66-72,共7页
Gaseous detonation propagating in a toroidal chamber was numerically studied for hydrogen/oxygen/nitrogen mixtures. The numerical method used is based on the three-dimensional Euler equations with detailed finiterate ... Gaseous detonation propagating in a toroidal chamber was numerically studied for hydrogen/oxygen/nitrogen mixtures. The numerical method used is based on the three-dimensional Euler equations with detailed finiterate chemistry. The results show that the calculated streak picture is in qualitative agreement with the picture recorded by a high speed streak camera from published literature. The three-dimensional flow field induced by a continuously rotating detonation was visualized and distinctive features of the rotating detonations were clearly depicted. Owing to the unconfined character of detonation wavelet, a deficit of detonation parameters was observed. Due to the effects of wall geometries, the strength of the outside detonation front is stronger than that of the inside portion. The detonation thus propagates with a constant circular velocity. Numerical simulation also shows three-dimensional rotating detonation structures, which display specific feature of the detonation- shock combined wave. Discrete burning gas pockets are formed due to instability of the discontinuity. It is believed that the present study could give an insight into the interest- ing properties of the continuously rotating detonation, and is thus beneficial to the design of continuous detonation propulsion systems. 展开更多
关键词 Continuously rotating detonation - Three- dimensional flow field structure - Numerical study Detonation parameters deficit ~ Effects of wall geometries
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Strategies for accurate response assessment of radiochromic film using flatbed scanner for beam quality assurance 被引量:1
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作者 xu-dong zhang Yuan-Hao Liu +7 位作者 Xiao-Bin Tang Ming-Chen Hsiao Wei-Lin Chen Chang-Ran Geng Wen-Cheng Shao Chun-Hui Gong Silva Bortolussi Di-Yun Shu 《Nuclear Science and Techniques》 SCIE CAS CSCD 2019年第11期1-9,共9页
Radiochromic film is a useful tool for beam quality assurance, but accurate response assessment of the film is still a problem. In this study, the response uncertainties of HDV2 film were investigated using a flatbed ... Radiochromic film is a useful tool for beam quality assurance, but accurate response assessment of the film is still a problem. In this study, the response uncertainties of HDV2 film were investigated using a flatbed scanner from both the scanning settings and interscan variability. Scanning settings are fixed conditions for scanning, including scanning resolution and focus setting.In this study, multipeak distributions of pixel values were found under some dots-per-inch values, which should be avoided, and the optimal setting of 2000 dpi without this problem was selected. By changing the focus setting, the relative standard deviation of pixel values was reduced by 36–50%. The influence of the interscan variability induced by three factors was investigated, including the outside illumination intensity, film homogeneity, and operating temperature. Scanning the film before and after irradiation at the same position was recommended. Moreover, the suitable operating temperature range for the scanner was found to be 15–24 °C, which results in stable film responses. Regarding the studied factors, correction methods and strategies were proposed, and the accurate response assessment of HDV2 film was realized. Finally, a standard operating procedure for response assessment of films was introduced. It can help other researchers study more scanners, films, and particle types. 展开更多
关键词 Radiochromic film Response assessment SCANNING SETTING Interscan VARIABILITY Standard operating procedure
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Contact binaries at different evolutionary stages 被引量:1
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作者 Sheng-Bang Qian Li-Ying Zhu +4 位作者 Liang Liu xu-dong zhang Xiang-Dong Shi Jia-Jia He Jia zhang 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2020年第10期229-248,共20页
Contact binaries consist of two strongly interacting component stars where they are filling their critical Roche lobes and sharing a common envelope.Most of them are main-sequence stars,but some of them are post main-... Contact binaries consist of two strongly interacting component stars where they are filling their critical Roche lobes and sharing a common envelope.Most of them are main-sequence stars,but some of them are post main-sequence systems.They are good astrophysical laboratories for studying several problems such as the merging of binary stars,evolution of the common envelope,the origin of luminous red nova outbursts and the formation of rapidly rotating single stars with possible planetary systems.A large number of contact binary candidates were detected by several photometric surveys around the world and many of them were observed by the LAMOST spectroscopic survey.Based on follow-up observations,the evolutionary states and geometrical structures of some systems were understood well.In this review,we will introduce and catalog new stellar atmospheric parameters(i.e.,the effective temperature(Teff),the gravitational acceleration(log(g)),metallicity([Fe/H])and radial velocity(Vr))for 9149 EW-type contact binaries that were obtained based on low-and medium-resolution spectroscopic surveys of LAMOST.Then we will focus on several groups of contact binary stars,i.e.,marginal contact binary systems,deep and low-mass ratio contact binary stars,binary systems below the short-period limit of contact binaries and evolved contact binaries.Marginal contact binaries are at the beginning of the contact stage,while deep and low-mass ratio contact binary stars are at the final evolutionary stage of tidally locked binaries.Several statistical relations including the period-temperature relation are determined well by applying LAMOST data and their formation and evolutionary states are reviewed.The period-color relation of M-type binaries reveals that there are contact binaries below the short-period limit.Searching for and investigating contact binaries near and below this limit will help us to understand the formation of contact binary systems and a new prediction for the short-period limit is about 0.15 d.Some evolved contact binaries were detected by the LAMOST survey where both components are sub-giants or giants.They provide a good opportunity to investigate evolution of the common envelope and are the progenitors of luminous red novae like V1309 Sco. 展开更多
关键词 binaries:eclipsing stars:late-type stars:low-mass stars:formation stars:evolution
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Investigation of factors affecting vertical sag of stretched wire
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作者 Jian-Dong Yuan Jun-Xia Wu +7 位作者 Bin zhang Yuan He Jun-Hui zhang Wen-Jun Chen Shao-Ming Wang Guo-Zhen Sun xu-dong zhang Li-Song Yan 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2021年第2期90-100,共11页
To study vertical sag requirements and factors affecting the stretched wire alignment method,the vertical sag equation is first derived theoretically.Subsequently,the influencing factors(such as the hanging weight or ... To study vertical sag requirements and factors affecting the stretched wire alignment method,the vertical sag equation is first derived theoretically.Subsequently,the influencing factors(such as the hanging weight or tension,span length,temperature change,elastic deformation,and the Earth’s rotation)of the vertical sag are summarized,and their validity is verified through actual measurements.Finally,the essential factors affecting vertical sag,i.e.,the specific strength and length,are discussed.It is believed that the vertical sag of a stretched wire is proportional to the square of the length and inversely proportional to the specific strength of the material. 展开更多
关键词 Stretched wire Alignment Vertical sag CATENARY Hyperbolic cosine Linear density Earth rotation
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Effect of structural vacancies on lattice vibration,mechanical,electronic,and thermodynamic properties of Cr5BSi3
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作者 董天慧 张旭东 +1 位作者 杨林梅 王峰 《Chinese Physics B》 SCIE EI CAS CSCD 2022年第2期496-502,共7页
In recent years,transition metal silicides have become the potential high temperature materials.The ternary silicide has attracted the attention of scientists and researchers.But their inherent brittle behaviors hinde... In recent years,transition metal silicides have become the potential high temperature materials.The ternary silicide has attracted the attention of scientists and researchers.But their inherent brittle behaviors hinder their wide applications.In this work,we use the first-principles method to design four vacancy defects and discuss the effects of vacancy defects on the structural stability,mechanical properties,electronic and thermodynamic properties of hexagonal Cr;BSi;silicide.The data of lattice vibration and thermodynamic parameters indicate that the Cr;BSi;with different atomic vacancies can possess the structural stabilities.The different atomic vacancies change the mechanical properties and induce the Cr;BSi;to implement the brittle-to-ductile transition.The shear deformation resistance and volume deformation resistance of Cr;BSi;are weakened by different vacancy defects.But the brittleness behavior is remarkably improved.The structural stability and brittle-to-ductile transition of Cr;BSi;with different vacancies are explored by the electronic structures.Moreover,the thermal parameters indicate that the Cr;BSi;with vacancies exhibit different thermodynamic properties with temperature rising. 展开更多
关键词 vacancies in Cr5BSi3 brittle-to-ductile transition electronic properties thermodynamic properties
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CSS J075415.6+191052 and NW Leo: Two Contact Binaries at Different Evolutionary Stages
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作者 xu-dong zhang Sheng-Bang Qian +3 位作者 Er-Gang Zhao Qi-Jun Zhi Ai-Jun Dong Bin zhang 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2022年第2期118-127,共10页
Multi-color light curves of CSS J075415.6+191052 and NW Leo are presented and the photometric solutions suggest that CSS J075415.6+191052 is an A-subtype contact binary with low mass ratio(q = 0.178) while NW Leo has ... Multi-color light curves of CSS J075415.6+191052 and NW Leo are presented and the photometric solutions suggest that CSS J075415.6+191052 is an A-subtype contact binary with low mass ratio(q = 0.178) while NW Leo has a high mass ratio(q = 0.707). For CSS J075415.6+191052, the RI light curves show weakening around the left shoulder of the secondary minimum, which indicates that there may be a dark spot on the secondary component. However, the light curves of BV bands are totally symmetric. It is unreasonable if the dark spot is caused by magnetic activity or mass transfer between the two components. Therefore, weakening of the light curves in this contact binary is caused by something else. A possible explanation is mass transferring from the primary component to the common convective envelope through the inner Lagrangian point, and this part of the mass, for some reason, weakens the RI bands of light from the secondary component. O-C analysis of NW Leo reveals a cyclic period change with a modulation period of 4.7 yr, which may be caused by the light travel time effect of a third body. The positions of CSS J075415.6+191052 and NW Leo in the P–J′_(orb)diagram indicate that CSS J075415.6+191052 mainly abides by the angular momentum loss theory while NW Leo is dominated by the thermal relaxation oscillation theory. 展开更多
关键词 (stars:)binaries:eclipsing stars:evolution stars:individual(CSS J075415.6+191052 NW Leo)
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Reanalysis of the orbital period variations of two DLMR overcontact binaries:FG Hya and GR Vir
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作者 xu-dong zhang Yun-Xia Yu +1 位作者 Fu-Yuan Xiang Ke Hu 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2017年第12期95-100,共6页
We investigate orbital period changes of two deep, low mass ratio(DLMR) overcontact W UMa-type binaries, FG Hya and GR Vir. It is found that the orbital period of FG Hya shows a cyclic change with a period of Pmod= ... We investigate orbital period changes of two deep, low mass ratio(DLMR) overcontact W UMa-type binaries, FG Hya and GR Vir. It is found that the orbital period of FG Hya shows a cyclic change with a period of Pmod= 54.44 yr. The cyclic oscillation may be due to a third body in an eccentric orbit, while the orbital period of GR Vir shows a periodic variation with a period of Pmod= 28.56 yr and an amplitude of A = 0.0352 d. The periodic variation of GR Vir can be interpreted as a result of either the light-time effect of an unseen third body or the magnetic activity cycle. 展开更多
关键词 binaries:close binaries:eclipsing stars:individual(FG Hya GR Vir)
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Reaction characteristics of carbon-bearing pellets of Bayan Obo lean iron ores in a static magnetic field
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作者 Yong-li Jin Jin-tao Jiang +2 位作者 Hong-xing Dai xu-dong zhang Zeng-wu Zhao 《Journal of Iron and Steel Research(International)》 SCIE EI CAS CSCD 2023年第9期1687-1700,共14页
The use of low-grade,refractory and composite paragenetic mineral resources is necessary for overcoming the shortage of iron ore resources in China.As a solution to the treatment of such iron ores,the direct reduction... The use of low-grade,refractory and composite paragenetic mineral resources is necessary for overcoming the shortage of iron ore resources in China.As a solution to the treatment of such iron ores,the direct reduction of carbon-bearing pellets can ensure complete iron removal and the effective enrichment of other high-value elements.Thus,this technology enjoys a broad application prospect.However,there are several problems with low-temperature reduction,such as low iron ore reaction efficiency,long reaction time,and high energy consumption.To improve the low-temperature carbothermic reduction efficiency of iron ores,a static magnetic field with magnetic induction intensity of 1.0 T was introduced.An isothermal reduction experiment was conducted at 1223 K to study the low-temperature self-reduction characteristics of carbon-bearing pellets of Bayan Obo lean iron ores in the static magnetic field.Also,the acting mechanism of the magnetic field was explored from the perspective of the reduction process,reaction efficiency,phase composition,microstructure changes,and dynamic behavior of iron ores.The results showed that the magnetic field can increase the low-temperature reduction rate of carbon-bearing pellets of Bayan Obo lean iron ores.Under the conditions of reduction temperature of 1223 K,magnetic induction intensity of 1.0 T,and reduction time of 60 min,the reduction degree was 92.42%,1.65 times that without a magnetic field.The magnetic field promoted the replacement of Ca^(2+)and Fe^(2+),so that the hard-to-reduce iron-bearing silicates were reduced in the order of Fe2SiO_(4)→(Ca,Na)FeSiO_(4)→FeO→Fe.The magnetic field enabled loose minerals,more pores and cracks,and changes in the growth morphology and distribution position of metallic iron.Compared with the case under the non-magnetic condition,the metallic iron precipitated from the slag phase in a foliated shape,separated from the matrix iron oxides,and grew up at the junction of the slag phase and coke.The magnetic field significantly increased the interfacial chemical reaction rate of the carbothermic reduction of iron ores and reduced the internal diffusion resistance of gas in the product layer.Specifically,the interfacial chemical reaction rate increased by 138%and the internal diffusion coefficient increased by 309%.Therefore,the effect of the magnetic field on the internal diffusion resistance was the main cause for strengthening the low-temperature reduction of iron ores. 展开更多
关键词 Static magnetic field Bayan obo lean iron ore Carbon-bearing pellet Reduction rate Phase evolution Dynamic behavior
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Metatranscriptome of human lung microbial communities in a cohort of mechanically ventilated COVID-19 Omicron patients
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作者 Lin Wang Jia-Bao Cao +31 位作者 Bin-Bin Xia Yue-Juan Li Xuan zhang Guo-Xin Mo Rui-Juan Wang Si-Qi Guo Yu-Qing zhang Kun Xiao Guang-Fa Zhu Peng-Fei Liu Li-Cheng Song Xi-Hui Ma Ping-Chao Xiang Jiang Wang Yu-Hong Liu Fei Xie xu-dong zhang Xiang-Xin Li Wan-Lu Sun Yan Cao Kai-Fei Wang Wen-Hui zhang Wei-Chao Zhao Peng Yan Ji-Chao Chen Yu-Wei Yang Zhong-Kuo Yu Jing-Si Tang Li Xiao Jie-Min Zhou Li-Xin Xie Jun Wang 《Signal Transduction and Targeted Therapy》 SCIE CSCD 2023年第12期5919-5930,共12页
The Omicron variant of the severe acute respiratory syndrome coronavirus 2(SARS‑CoV‑2)infected a substantial proportion of Chinese population,and understanding the factors underlying the severity of the disease and fa... The Omicron variant of the severe acute respiratory syndrome coronavirus 2(SARS‑CoV‑2)infected a substantial proportion of Chinese population,and understanding the factors underlying the severity of the disease and fatality is valuable for future prevention and clinical treatment.We recruited 64 patients with invasive ventilation for COVID-19 and performed metatranscriptomic sequencing to profile host transcriptomic profiles,plus viral,bacterial,and fungal content,as well as virulence factors and examined their relationships to 28-day mortality were examined.In addition,the bronchoalveolar lavage fluid(BALF)samples from invasive ventilated hospital/community-acquired pneumonia patients(HAP/CAP)sampled in 2019 were included for comparison.Genomic analysis revealed that all Omicron strains belong to BA.5 and BF.7 sub-lineages,with no difference in 28-day mortality between them.Compared to HAP/CAP cohort,invasive ventilated COVID-19 patients have distinct host transcriptomic and microbial signatures in the lower respiratory tract;and in the COVID-19 non-survivors,we found significantly lower gene expressions in pathways related viral processes and positive regulation of protein localization to plasma membrane,higher abundance of opportunistic pathogens including bacterial Alloprevotella,Caulobacter,Escherichia-Shigella,Ralstonia and fungal Aspergillus sydowii and Penicillium rubens.Correlational analysis further revealed significant associations between host immune responses and microbial compositions,besides synergy within viral,bacterial,and fungal pathogens.Our study presents the relationships of lower respiratory tract microbiome and transcriptome in invasive ventilated COVID-19 patients,providing the basis for future clinical treatment and reduction of fatality. 展开更多
关键词 PATIENTS MORTALITY PREVENTION
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Comparison of the closed analytical solution on the parameters of the alignment and surveying of the elements of accelerator under random errors
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作者 Jian-Dong Yuan Jun-Xia Wu +8 位作者 Feng-Feng Wang Wen-Jun Chen Guo-Zhen Sun Shao-Ming Wang xu-dong zhang Xiao-Dong zhang Zhi-Jun Wang Bin zhang Yuan He&Jun-Hui zhang 《Radiation Detection Technology and Methods》 CSCD 2023年第2期234-247,共14页
Purpose Compared with the iterative approximation solution,the analytically rigorous solution of the parameters of the accelerator alignment and surveying is the closed theoretical solution.To make the calculated erro... Purpose Compared with the iterative approximation solution,the analytically rigorous solution of the parameters of the accelerator alignment and surveying is the closed theoretical solution.To make the calculated error meet the negligible principle,in this paper,such examples of the zero,small angle and small translation,only large translation and no angle,only large angle without translation and large translation and large angle parameters under random errors are constructed.Methods Furthermore,Singular Value Decomposition,Eigen Value Decomposition,Polar Decomposition,Orthogonal Procrustes Analysis,and Successive Equivalent Differences Transformation are compared.Results In all the above examples,the mutual calculation deviation of Singular Value Decomposition,Eigen Value Decomposition,Polar Decomposition,and Orthogonal Procrustes analysis methods is less than 10 um.Its calculation accuracy is the highest,and Successive Equivalent Differences Transformation-3 has the largest calculation error,and Successive Equivalent Differences Transformation-N is in the middle.The results show that the coordinate residuals,parameters offsets and point position errors of the above solutions with random errors are all nearly zero.Conclusion It shows that the closed analytical solution is a rigorous solution.Moreover,it also shows that the constructed method of the coordinate point pairs is correct. 展开更多
关键词 ACCELERATOR ALIGNMENT SURVEYING Closed analytical solution
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