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大空间张拉索膜结构分析与优化

低温建筑技术 2022年第10期44卷 98-102页

作者：武宗良张贵阳韩爱红孙建良华北水利水电大学土木与交通学院郑州450008

为确保某大空间张拉索膜结构的安全性,提高结构质量以及节约资源,采用3D3S软件对该结构进行有限元计算及优化分析。结果表明结构中部桁架产生的挠度最大,膜面最大位移主要分布在膜结构外侧,结构整体受力不均匀。针对结构受力特性以及防... 详细信息

为确保某大空间张拉索膜结构的安全性,提高结构质量以及节约资源,采用3D3S软件对该结构进行有限元计算及优化分析。结果表明结构中部桁架产生的挠度最大,膜面最大位移主要分布在膜结构外侧,结构整体受力不均匀。针对结构受力特性以及防止膜面位移过大产生不利影响,对结构进行了整体模拟计算分析,重点对钢骨架结构和索膜结构进行了位移分析和内力分析,对钢管桁架的钢管截面进行了优化,并提出了增大膜预张力及索预拉力以减小膜面位移的有效方法,优化后的结构满足规范要求,既有效的控制结构变形又减少了工程用钢量。

关键词：索膜结构钢管桁架有限元分析优化分析

Multiwavelength Observations of the Infrared Dust Bubble N75 and its Surroundings

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Research in Astronomy and Astrophysics 2024年第4期24卷 262-270页

作者： Quan-Ling Cui Chuan-Peng zhang Jun-Jie Wang National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China College of Science Qiqihar UniversityQiqihar 161006China Guizhou Radio Astronomical Observatory Guizhou UniversityGuiyang 550000China

Infrared dust bubbles play an important role in the study of star formation and the evolution of the interstellar *** this work,we study the infrared dust bubble N75 and the infrared dark cloud G38.93 mainly using the tracers C^(18)O,HCO^(+),HNC and N_(2)H^(+)observed by the 30 m IRAM *** also study the targets using data from large-scale surveys:GLIMPSE,MIPSGAL,GRS,NRAO VLA Sky Survey and Bolocam Galactic Plane *** found that the C^(18)O emission is morphologically similar to the Spitzer IRAC 8.0μm ***1.1 mm cold dust emission of G38.93 shows an elongated structure from southwest to *** ionized gas from G38.93 is surrounded by polycyclic aromatic hydrocarbon emission,which may be excited by radiation from *** found that the identified young stellar objects tend to cluster around G38.93 and are mostly in class II with several class I cases distributed around N75,but no class II *** also found evidence of expanding feedback,which could have triggered star formation.

关键词： ISM:bubbles infrared:ISM galaxies:star formation

Possible Habitats for NH_(3),NH_(2)D,H^(13)CN,HC^(15)N,SO,and C^(18)O in the Initial Conditions of High-mass Star Formation

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Research in Astronomy and Astrophysics 2024年第4期24卷 237-252页

The initial condition of high-mass star formation is a complex area of study because of the high densities(n_(H_(2))>106cm^(-3))and low temperatures(T_(dust)<18 K)*** such conditions,many molecules become depleted from the gas phase by freezing out onto dust ***,the N-bearing and deuterated species could remain gaseous under these extreme conditions,suggesting that they may serve as ideal *** this paper,using the Plateau de Bure Interferometer and Very Large Array observations at 1.3 mm,3.5 mm,and 1.3 cm,we investigate the possible habitats for NH_(3),NH_(2)D,H^(13)CN,HC^(15)N,SO,and C^(18)O in eight massive precluster and protocluster clumps G18.17,G18.21,G23.97N,G23.98,G23.44,G23.97S,G25.38,and *** found that the NH3cores are in good agreement with the 3.5 mm peak emission,but the NH_(3)is much more extended than the 3.5 mm emission *** SO distributions agree well with the 3.5 mm peaks for the evolved star formation stage,but we did not detect any SO emission in the four earliest star formation sources.C^(18)O is a poor tracer in conditions of the cold(■18 K)and dense(■10^(4)cm^(-3))cores,e.g.,the prestellar *** also found that the NH_(2)D cores are mainly located in the temperature range of 13.0-20.0 K,and the NH_(2)D lines may be strongly depleted above 20 K.

关键词： galaxies:star formation techniques:interferometric methods:observational

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小型膨化试验机的研发与应用

饲料博览 2023年第1期 24-27页

作者：董飚张贵阳吴晶贺凯林孙翔江苏丰尚智能科技有限公司江苏扬州225127 国家饲料加工装备工程技术研究中心江苏扬州225127

小型膨化试验机以其灵活性及低成本的优势适合于试验研究使用。文章介绍了SJPS42×2双螺杆小型膨化试验机研制时的参数选择,并对该产品在试验应用过程中的优势进行了总结,试验应用的结果表明本设备能满足水产饲料和宠物饲料的试验研究。

关键词：双螺杆膨化机挤压加工设计试验

A discovery of two slow pulsars with FAST:“Ronin”from the globular cluster M15

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Science China(Physics,Mechanics & Astronomy) 2024年第6期67卷 166-180页

作者： Dengke Zhou Pei Wang Di Li Jianhua Fang Chenchen Miao Paulo CCFreire Lei zhang Dandan zhang Huaxi Chen Yi Feng Yifan Xiao Jintao Xie Xu zhang Chenwu Jin Han Wang Yinan Ke Xuerong Guo Rushuang Zhao Chenhui Niu Weiwei Zhu Mengyao Xue Yabiao Wang Jiafu Wu Zhenye Gan Zhongyi Sun Chengjie Wang Jie zhang Junshuo zhang Jinhuang Cao Wanjin Lu Research Center for Astronomical Computing Zhejiang LaboratoryHangzhou 311121China National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China Institute for Frontiers in Astronomy and Astrophysics Beijing Normal UniversityBeijing 102206China University of Chinese Academy of Sciences Beijing 100049China New Cornerstone Science Laboratory Shenzhen 518054China Max Planck Institut f¨ur Radioastronomie Bonn 53121Germany Centre for Astrophysics and Supercomputing Swinburne University of TechnologyHawthorn 3122Australia School of Mathematical Sciences School of Physics and Electronic SciencesGuizhou Normal UniversityGuiyang 550001China Guizhou Provincial Key Laboratory of Radio Astronomy and Data Processing Guiyang 550001China School of Physics and Electronic Engineering Qilu Normal UniversityJinan 250200China School of Physics and Electronic Science Guizhou Normal UniversityGuiyang 550001China College of Physical Science and Technology Central China Normal UniversityWuhan 430079China Tencent Youtu Lab Shanghai 201103China

Globular clusters harbor numerous millisecond pulsars,but long-period pulsars(P 100 ms)are rarely *** this study,we employed a fast folding algorithm to analyze observational data from multiple globular clusters obtained by the Five-hundredmeter Aperture Spherical radio Telescope(FAST),aiming to detect the existence of long-period *** estimated the impact of the median filtering algorithm in eliminating red noise on the minimum detectable flux density(S_(min))of ***,we successfully discovered two isolated long-period pulsars in M15 with periods approximately equal to 1.928451 and3.960716 s,*** the P-˙P diagram,both pulsars are positioned below the spin-up line,suggesting a possible history of partial recycling in X-ray binary systems disrupted by dynamical encounters later *** to timing results,these two pulsars exhibit remarkably strong magnetic *** the magnetic fields were weakened during the accretion process,then a short duration of accretion might explain the strong magnetic fields of these pulsars.

关键词： pulsar globular cluster FAST

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Trace elements in magmatic and hydrothermal quartz:Implications on the genesis of the Xingluokeng Tungsten Deposit,South China

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Acta Geochimica 2024年第3期43卷 441-458页

作者： Qing-Qing zhang You-Wei Chen Jian-Feng Gao State Key Laboratory of Ore Deposit Geochemistry Institute of GeochemistryChinese Academy of SciencesGuiyang 550081China University of Chinese Academy of Sciences Beijing 100049China

The Xingluokeng deposit is the largest gran-ite-related tungsten deposit within the Wuyi metallogenic belt in South *** Xingluokeng intrusion primarily consists of porphyritic biotite granite,biotite granite,andfine-grained *** deposit is represented by veinlet-disseminated mineralization with K-feldspathization and biotitization,alongside quartz-vein mineralization with gre-isenization and *** study investigates in-situ analyses of quartz compositions from both the intrusion and hydrothermal veinlets and *** element correlations indicate that trivalent Al^(3+)and Fe^(3+)replace Si^(4+)within the quartz lattice,with monovalent cations(such as Li^(+),Na^(+),and K^(+))primarily serving as charge *** Ge/Al ratios(<0.013)of quartz from granites suggest a mag-matic *** low Al/Ti and Ge/Ti ratios,accompanied by high Ti contents in quartz,suggest that the porphyritic biotite granite and biotite granite are characterized by rela-tively low levels of differentiation and high crystallization *** contrast,thefine-grained granite exhibits a higher degree of fractionation,lower crystallization tem-peratures,and a closer association with tungsten *** contents in quartz from quartz veins indicate Qz-Ⅰformed at temperatures above 400°C,while Qz-Ⅱto Qz-Ⅴformed at temperatures below 350°*** in different generations of quartz,as indicated by Al content and(Al+Fe)/(Li+Na+K)ratio,suggest that Qz-Ⅰprecipi-tated from a less acidicfluid with a stable pH,whereas Qz-Ⅱto Qz-Ⅴoriginated from a more acidicfluid with notable pH ***,alkaline alteration and acidic alteration supplied the essential Ca and Fe for the precipita-tion of scheelite and wolframite,respectively,highlighting a critical mechanism in tungsten mineralization at the Xin-gluokeng deposit.

关键词： Quartz Xingluokeng Tungsten deposit Trace elements South China

Petrogenesis and Tectonic Implications of the Paleoproterozoic A-Type Granites in the Xiong’ershan Area along the Southern Margin of the North China Craton

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Journal of Earth Science 2024年第2期35卷 416-429页

作者： Jinhong Xu Yuping Jiang Shuli Hu Zhengwei zhang Chengquan Wu Chaofei Zheng Xiyao Li Ziru Jin Sensen zhang Yatao Zhou State Key Laboratory of Ore Deposit Geochemistry Institute of GeochemistryChinese Academy of SciencesGuiyang550081China University of Chinese Academy of Sciences Beijing100049China Henan Province Non-ferrous Metals Geological Mineral Resources Bureau Zhengzhou450053China Jiangmen Land Market Monitoring Center Jiangmen 529000China

Paleoproterozoic A-type granites are widely distributed in the southern margin of the North China Craton(SNCC),providing important information for understanding the Paleoproterozoic tectonic regimes in this *** paper reports newly obtained whole-rock compositions and zircon U-Pb ages for the Tieluping syenogranite porphyry(TLP)and Huoshenmiao alkali granite porphyry(HSM)in the *** from the TLP and HSM have U-Pb ages of 1805±12 and 1792±14 Ma,*** ages are taken to date the emplacement of these *** had high total alkali contents(K_(2)O+Na_(2)O>7.13 wt.%),with high 10000×Ga/Al ratios(3.06–3.41)and Zr+Y+Nb+Ce values(709 ppm–910 ppm)as well as high zircon saturation temperatures(864–970℃),indicative of A-type granite *** Y/Nb(1.75–3.32),Ce/Nb(7.72–9.72),and Yb/Ta(2.89–5.60)ratios suggested that TLP and HSM belonged to the A2-type *** negative whole rockε_(Nd)(t)values(−8.4 to−6.6)and negative zirconε_(Hf)(t)values(−15.9 to−6.3)confirmed that TLP and HSM were likely generated by the partial melting of an ancient continental ***εHf(t)(−7.4 to+4.0)values of inherited zircons in the TLP suggested that they were derived from the partial melting of Archean basement *** the geochemical similarity of the 1.80 Ga A-type granitoids in the SNCC,we propose that the TLP and HSM were formed in a post-collisional regime that was likely associated with the break-off of the Paleoproterozoic subducted *** of the asthenosphere provided huge heat to generate the regional 1.80 Ga A-type granite in the SNCC.

关键词： Paleoproterozoic A-type granite Post-collisional North China Craton tectonic geochemistry

Discovery and structure-activity relationship studies of novel tetrahydro-β-carboline derivatives as apoptosis initiators for treating bacterial infections

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Journal of Integrative Agriculture 2024年第4期23卷 1259-1273页

作者： Shanshan Su Hongwu Liu Junrong zhang Puying Qi Yue Ding Ling zhang Linli Yang Liwei Liu Xiang Zhou Song Yang National Key Laboratory of Green Pesticide/Key Laboratory of Green Pesticide and Agricultural Bioengineering Ministry of Education/Center for R&D of Fine ChemicalsGuizhou UniversityGuiyang 550025China

Developing and excavating new agrochemicals with highly active and safe is an important tactic for protecting crop health and food *** this paper,to discover the new bactericide candidates,we designed,prepared a new type of1,2,3,4-tetrahydro-β-carboline(THC)derivatives and evaluated the in vitro and in vivo bioactivities against the Xanthomonas oryzae ***(Xoo),Xanthomonas axonopodis ***(Xac),and Pseudomonas syringae ***(Psa).The in vitro bioassay results exhibited that most title molecules possessed good activity toward the three plant pathogenic bacteria,the compound A17 showed the most active against Xoo and Xac with EC50 values of 7.27 and 4.89 mg mL^(-1)respectively,and compound A8 exhibited the best inhibitory activity against Psa with EC50value of 4.87 mg mL^(-1).Pot experiments showed that compound A17 exhibited excellent in vivo antibacterial activities to manage rice bacterial leaf blight and citrus bacterial canker,with protective efficiencies of 52.67 and 79.79%at 200 mgmL^(-1),***,compound A8 showed good control efficiency(84.31%)against kiwifruit bacterial canker at 200 mg mL^(-1).Antibacterial mechanism suggested that these compounds could interfere with the balance of the redox system,damage the cell membrane,and induce the apoptosis of Xoo *** together,our study revealed that tetrahydro-β-carboline derivatives could be a promising candidate model for novel broadspectrum bactericides.

关键词： tetrahydro-β-carboline derivatives antibacterial activity ROS cell apoptosis

Efficacy and safety of transvaginal mesh repair in a cohort with a minimum of 10-year follow-up

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Science China(Life Sciences) 2024年第5期67卷 1061-1068页

作者： Zhibo zhang Jianbin Guo Weijie Tian Ye zhang Yuelun zhang Tianshu Sun Jiali Duan Xinmiao Bao Yuan Wang Yang Ye Qianqian Gao Honghui Shi Abraham Nick Morse Juan Chen Lan Zhu Departmentof Obstetrics and Gynecology Peking Union MedicalCollege HospitalChinese Academyof Medical Sciences&Peking Union MedicalCollegeNational Clinical Research Center for Obstetricand Gynecologic DiseasesBeijing 100730China Department of Gynecology Guizhou Provincial People’s HospitalMedical College of Guizhou UniversityGuiyang 550002China Department of Obstetrics and Gynecology The First Affiliated Hospital of Zhengzhou UniversityZhengzhou 450000China Medical Research Center Peking Union Medical College HospitalChinese Academy of Medical Sciences&Peking Union Medical CollegeBeijing 100730China Medical Doctor Program Chinese Academy of Medical Sciences&Peking Union Medical CollegeBeijing 100730China Department of Pathology Peking Union Medical College HospitalBeijing 100730China Tufts University School of Medicine Boston MA 02111USA

Although transvaginal mesh(TVM)repair is no longer used in some countries,long-term outcomes after TVM surgery are of great importance ***,reports with follow-up>10 years are ***,this study aimed to report outcomes in a prospective cohort with at least 10 years of *** with stageⅢ–Ⅳsymptomatic prolapse were approached consecutively from 2008 to 2013 at one tertiary *** main outcome measure was symptomatic *** outcomes included anatomic failure,recurrence,patient satisfaction,complications,and *** Kaplan-Meier curve was used to estimate the cumulative failure *** the 121 patients enrolled in the study,103(85.1%)completed a median follow-up of 11 *** estimated probability rates of symptomatic and anatomic failure were 17.6%and 8.8%in 11 years,*** estimated incidence of symptomatic failure increased by 8.2%between 5 and 11 years;however,the corresponding rate for anatomic failure was 3.7%.The most common complication was vaginal mesh exposure,and its estimated probability increased from 19.3%to 28.4%from 5 to 11 years,*** trimming resolved 80.0%of vaginal *** patients did not report decreased overall *** with vaginal mesh exposure requiring>3 office procedures or mesh removal in the operating room(5.8%by 11 years)had lower satisfaction rates(P<0.01)and were defined as having severe mesh *** rates of postoperative pain,reoperation,and Patient Global Impression of Improvement≥2 were 2.5%,3.3%,and 94.2%,*** results of this study implied that TVM treatment gradually increased the symptomatic failure rate but provided durable anatomical support of the vaginal *** mesh exposure was common in women who were largely not sexually active;however,80%of the cases could be managed in the outpatient clinic,which did not affect patient satisfaction.

关键词： complication efficacy long-term follow-up pelvic organ prolapse safety transvaginal mesh

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