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The ecological sequence of Hipparion fauna in the middle reaches of the Yellow River during Neogene

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Chinese Science Bulletin 2002年第1期47卷 79-82页

作者： zhang yunxiang YUE Leping CAO Hongxia The Key Laboratory of Northwest University Continental Dynamics Ministry of EducationChinaXi’an 7J0069China Institute of Earth Environment Chinese Academy of SciencesXi’an 710069China

The faunal ecological type and sequence in the Tertiary red clay indicate that Hipparion fauna during the period 7.4-6.1 Ma in the middle reaches of the Yellow River is composed mainly of dorcadoides and mixed types. This represents semiarid veld environment with small fluctuation. The fossil assemblages characterized by the abundance of gaudryi types and even the occurrence of some Hominoid and Chalicotherium indicate an obviously warm and humid period since 5.3 Ma. The fossil assemblages during 3.4 Ma show the typical steppe fauna representing dry climate. It is indicated by the changes of ecological sequence that the cli-matic conditions in Pliocene are drier than that in late Mio-cene. The clay-skin content of red clay, which has a syn-chronous change with faunal features, is a rather good re-placing palaeoclimatic index.

关键词： Neogene red clay Hipparion fauna environment evolution.

Effects of stand density on soil respiration and labile organic carbon in different aged Larix principis-rupprechtii plantations

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Ecological Processes 2021年第1期10卷 582-596页

作者： Tairui Liu Daoli Peng Zhijie Tan Jinping Guo yunxiang zhang College of Forestry Beijing Forestry UniversityNo.35 Tsinghua East RoadHaidian DistrictBeijing 100083People’s Republic of China. Lvliang Bureau of Planning and Natural Resources Lüliang 033000People’s Republic of China. College of Forestry Shanxi Agricultural UniversityJingzhong 030801People’s Republic of China

Background:The carbon pools of forest soils play a vital role in global carbon sequestration and *** management can regulate the sequestration and output of forest soil carbon pools to a certain extent;however,the kinetics of the effects of forest density on soil carbon pools require further ***:We established sample plots with stand density gradients in three different aged Larix principis-rupprechtii plantations and quantified the soil respiration,soil organic carbon(SOC),soil dissolved organic carbon(DOC),microbial biomass carbon(MBC),light fraction organic carbon(LFOC),and readily oxidized carbon(ROC).Results and conclusions:During the growth and development of plantations,stand density is an essential factor that impacts soil respiration and its associated *** density was observed to promote both the soil and heterotrophic respiration rates and the sequestration of MBC and LFOC,whereas it inhibited the sequestration of *** soil,heterotrophic,and autotrophic respiration rates of older forest stands were relatively rapid,whereas the contents of SOC,MBC,LFOC,DOC,and ROC were higher and more sensitive to changes in stand *** MBC,LFOC,and ROC in soil labile organic carbon were closely related to both the soil and heterotrophic respiration,but not the *** them,the LFOC and MBC played the roles of“warehouse”and“tool”and were significantly correlated with soil and heterotrophic *** ROC,as a“raw material”,exhibited a significantly negative correlation with the soil and heterotrophic *** the soil and heterotrophic respiration rates were rapid,the ROC content in the soil maintained the low level of a“dynamically stabilized”*** stand density regulated heterotrophic respiration by affecting the soil labile organic carbon,which provided an essential path for the stand density to regulate soil respiration.

关键词： Stand density Soil respiration Soil organic carbon Soil labile organic carbon Influence mechanism

Investigation of Upconversion Luminescence Attenuation in Aqueous Solutions Under 980 nm and 808 nm Irradiation

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Journal of Analysis and Testing 2023年第4期7卷 377-383页

作者： Tianli Zhai Yanxin zhang Daoming Guan Lu Yang Wenrui zhang yunxiang zhang Qian Liu Department of Chemistry and Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials Fudan UniversityShanghai 200438China

Lanthanide ions-doped upconversion nanoparticles(UCNPs)have shown great potential in various biomedical ***,the upconversion luminescence(UCL)intensity of UCNPs in water environment tends to be *** quenching is typically attributed to non-radiative relaxation of the excited *** this study,we designed a core-shellshell-shell NaYb_(0.88)Er_(0.12)F_(4)@NaY_(0.9)b_(0.1)F_(4)@NaY_(0.6)Nd_(0.3)Yb_(0.1)F_(4)@NaYF_(4)UCNPs that could be excited by both 980 nm and 808 nm laser,due to the doping of Nd^(3+)and Yb^(3+)*** research not only utilized bulk spectral measurement but also employed single-particle level microscopic imaging to comprehensively investigate the impact of water molecules on UCL under 980 nm and 808 nm ***,our findings indicate that the absorption of water molecules has a significant effect on the UCL decay of UCNPs in aqueous solutions when excited by a 980 nm *** work offers a new perspective on the luminescence behavior of UCNPs in aquatic environments and provides valuable insights for their application and development in biomedicine.

关键词： UCNPs Upconversion luminescence Absorption of water molecules Single-particle imaging

New Discovery of Oligocene Gastropod Opercula from the Yehucheng Formation in Northwestern China

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Acta Geologica Sinica(English Edition) 2022年第1期96卷 61-70页

作者： LI Zhaoyu LI Yongxiang zhang yunxiang XIE Kun LI Zhichao State Key Laboratory of Continental Dynamics Department of GeologyNational Demonstration Center for Experimental Geology EducationInstitute of Cenozoic Geology and EnvironmentNorthwest UniversityXi’an 710069China School of Land Engineering Chang’an UniversityXi’an 710054China

Fourteen species of nonmarine gastropod opercula are found to be in high abundance in the Oligocene upper member of the Yehucheng Formation,Lanzhou Basin,northwest *** are attributed to two families,namely Bithyniidae and Assimineidae,and four genera,namely Pseudemmericia,Bithynia,Mirolaminatus and *** them,three species are new,and they are Bithynia paramonolithic ***.,*** ***.,and *** *** of these species were first discovered in Paleogene strata of the vast Northwest China and can be compared with the opercula recovered from the Paleogene deposits in East and South *** is inferred from the paleontology and sediment associations that the climate was slightly humid and the fauna probably inhabited the fresh or brackish water of a shallow lake in the Lanzhou Basin during the late early Oligocene period.

关键词： Lanzhou Basin early Oligocene Yehucheng Formation gastropod opercula

TEAD1/TEAD4基因多态性与非贲门胃癌变关系的研究

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安徽医科大学学报 2024年第5期59卷 863-868页

作者：阎小霞董文杰张云翔高芳贾彦彬包头医学院基础医学与法医学院包头014040 包头医学院医学技术与麻醉学院包头014040

目的探讨TEA转录因子1(TEAD1)基因单核苷酸多态性(SNP)rs2304733、TEA转录因子4(TEAD4)SNPrs7135838和rs1990330与非贲门胃癌变发病风险的关系。方法采用酶联免疫吸附测定法(ELISA)检测正常对照组血清样本中抗幽门螺杆菌(Hp)的特异性抗... 详细信息

目的探讨TEA转录因子1(TEAD1)基因单核苷酸多态性(SNP)rs2304733、TEA转录因子4(TEAD4)SNPrs7135838和rs1990330与非贲门胃癌变发病风险的关系。方法采用酶联免疫吸附测定法(ELISA)检测正常对照组血清样本中抗幽门螺杆菌(Hp)的特异性抗体,根据抗体滴度将470例正常对照组分为Hp感染阴性组(n=223)和阳性组(n=247)。在450例非贲门胃癌病例组和470例对照组中,采用聚合酶链式反应-限制性片段长度多态性(PCR-RFLP)技术对各SNP位点进行基因分型,采用非条件性Logistic回归评估各SNP位点与非贲门胃癌变发病风险的关系。结果TEAD1、TEAD4各SNP位点均与Hp感染没有关联;TEAD1 rs2304733与非贲门胃癌的发病风险相关,与携带TT基因型者相比,携带CT基因型及CC基因型者均增加了非贲门胃癌的发病风险(CTvsTT:OR=2.321,95%CI:1.690~3.188;CCvsTT:OR=5.140,95%CI:1.080~24.463);TEAD4 rs1990330与非贲门胃癌发病风险相关,与携带GG基因型者相比,携带GT基因型者增加了非贲门胃癌的发病风险(OR=2.405,95%CI:1.480~3.908);TEAD4 rs7135838与非贲门胃癌的发病风险无关联;TEAD1rs2304733、TEAD4 rs7135838以及rs1990330对非贲门胃癌发病风险存在交互作用(P<0.05)。结论在包头地区汉族人群中,TEAD1 rs2304733、TEAD4 rs1990330在Hp感染中不起主要作用,在非贲门胃癌发病风险中可能起一定作用;TEAD4 rs7135838在Hp感染以及非贲门胃癌发病风险中可能均不起主要作用;TEAD1 rs2304733、TEAD4 rs1990330对非贲门胃癌发病风险的协同效应最强,为最佳交互模型。

关键词： TEA转录因子1 TEA转录因子4 基因多态性幽门螺杆菌非贲门胃癌

HRB400E钢等温热处理过程中的奥氏体晶粒长大和钒析出物的影响

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金属热处理 2024年第8期49卷 15-21页

作者：陈石汪家晗张云祥骆艳萍孙钊洋叶传龙武汉科技大学材料学部湖北武汉430081 中冶南方工程技术有限公司湖北武汉430223

利用高温激光扫描共聚焦显微镜和透射电镜(TEM)等研究了含钒钢HRB400E在不同等温温度(950~1200℃)下保温30 min的加热过程中的奥氏体晶粒长大行为以及钒析出物对奥氏体晶粒长大的影响。结果表明,加热温度对试验钢奥氏体晶粒长大的影响... 详细信息

利用高温激光扫描共聚焦显微镜和透射电镜(TEM)等研究了含钒钢HRB400E在不同等温温度(950~1200℃)下保温30 min的加热过程中的奥氏体晶粒长大行为以及钒析出物对奥氏体晶粒长大的影响。结果表明,加热温度对试验钢奥氏体晶粒长大的影响明显大于保温时间,加热温度超过1100℃时,奥氏体晶粒等温长大速率明显加大。TEM观察表明钢中奥氏体晶粒长大行为受基体中V(C,N)粒子的影响,当加热温度为950℃时,钢中存在大量未溶的V(C,N)粒子,能有效钉扎奥氏体晶界,晶粒长大缓慢;当加热温度升高至1100℃时,随保温时间延长,细小的V(C,N)粒子溶解和粗化,钉扎效果下降,此时奥氏体晶粒快速长大。根据实测奥氏体晶粒尺寸结合Sellars模型和Anelli模型建立了试验钢奥氏体晶粒等温长大动力学模型,模型计算值与实测值吻合较好。

关键词：抗震钢HRB400E 奥氏体晶粒长大动力学模型 V(C N)析出物

SDH通信传输网络节点数据传输异常检测方法

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电力设备管理 2024年第6期 143-145页

作者：顾彬王义成张云翔郭焘国网江苏省电力有限公司信息通信分公司

由于传统方法在SDH通信传输网络节点数据传输异常检测中应用效果不佳,漏检率和误警率均比较高,无法达到预期的高精度检测效果,为此提出SDH通信传输网络节点数据传输异常检测方法。经实验证明,设计方法误检率与漏检率均未超过1%,具有较... 详细信息

由于传统方法在SDH通信传输网络节点数据传输异常检测中应用效果不佳,漏检率和误警率均比较高,无法达到预期的高精度检测效果,为此提出SDH通信传输网络节点数据传输异常检测方法。经实验证明,设计方法误检率与漏检率均未超过1%,具有较高的检测精度,在SDH通信传输网络节点数据传输异常检测方面具有良好的应用前景。

关键词： SDH通信传输网络节点数据传输异常数据驱动器小波分析技术

A New Fossil Erinaceidae from the Shajingyi Area in the Lanzhou Basin, China

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Acta Geologica Sinica(English Edition) 2019年第4期93卷 789-798页

作者： LI Zhichao LI Yongxiang XUE Xiangxu LI Wenhou zhang yunxiang YANG Fu School of Earth Science and Resources Chang’an UniversityXi’an 710054China State Key laboratory of Continental Dynamics Department of GeologyNorthwest UniversityXi’an 710069China Key Laboratory of Coal Resources Exploration and Comprehensive Utilization Ministry of Land and ResourcesXi’an 710021China

Here,we describe a new primitive Erinaceidae species,Oligoechinus lanzhouensis ***.,based on a specimen from late Oligocene strata of the Lanzhou Basin,Gansu *** characteristics are as follows:the M1 width is longer than the length,the metastyle extends far disto-labially,the posterior margin has strong curve and a distinct metaconule that is connected to the protocone by a postprotocrista is located in the centre of the *** posterior arm of the metaconule is poorly *** the P4,the pterion of the metastyle is less developed and the metacone is *** addition,*** has a premolar larger than the canine tooth(P2>C)and P3 had no molarisation,characters also possessed by ***,*** was similar to Mioechinus based on architectural tooth features,demonstrating a closed genetic *** Erinaceidae are relatively rare before the *** discovery of *** provides an important insight into the origin of Mioechinus in China and the early evolution of the *** analysis shows that a relatively recent ancestor of Mioechinus had probably existed in the early Oligocene and that *** was likely an ancestral type of Mioechinus gobiensis,and its systematic position should be located at a transitional position between Amphechinus and Mioechinus.

关键词： Erinaceidae Oligoechinus Lanzhou basin Oligocene

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SDH通信传输网络同频干扰告警方法

电力设备管理 2024年第3期 118-120页

作者：张云翔吴子辰顾彬王义成国网江苏省电力有限公司信息通信分公司

针对传统SDH通信传输网络同频干扰告警方法存在告警响应时间较长,以及误警率较高的问题,无法达到预期的告警效果,为此提出SDH通信传输网络同频干扰告警方法。利用脉冲采集器收集SDH通信传输网络信号,根据同频干扰噪声比对传输网络同频... 详细信息

针对传统SDH通信传输网络同频干扰告警方法存在告警响应时间较长,以及误警率较高的问题,无法达到预期的告警效果,为此提出SDH通信传输网络同频干扰告警方法。利用脉冲采集器收集SDH通信传输网络信号,根据同频干扰噪声比对传输网络同频干扰识别,利用赋权法对传输网络同频干扰程度评价,并且确定告警等级,利用告警器作出相应的告警响应,以此完成SDH通信传输网络同频干扰告警。经试验证明,设计方法告警响应时间在1s以内,误警率低于1%,设计方法在SDH通信传输网络同频干扰告警方面具有良好的应用前景。

关键词： SDH通信传输网络同频干扰告警脉冲采集器干扰噪声比