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Numerical investigation of geostress influence on the grouting reinforcement effectiveness of tunnel surrounding rock mass in fault fracture zones

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第1期16卷 81-101页

作者： Xiangyu Xu Zhijun Wu Lei Weng zhaofei Chu Quansheng liu Yuan Zhou The Key Laboratory of Safety for Geotechnical and Structural Engineering of Hubei Province School of Civil EngineeringWuhan UniversityWuhan430072China Wuhan University Shenzhen Research Institute Shenzhen518057China State Key Laboratory of Water Resources and Hydropower Engineering Science Wuhan UniversityWuhan430072China Institute of Rock and Soil Mechanics Chinese Academy of SciencesWuhan430071China

Grouting is a widely used approach to reinforce broken surrounding rock mass during the construction of underground tunnels in fault fracture zones,and its reinforcement effectiveness is highly affected by geostress.In this study,a numerical manifold method(NMM)based simulator has been developed to examine the impact of geostress conditions on grouting reinforcement during tunnel excavation.To develop this simulator,a detection technique for identifying slurry migration channels and an improved fluid-solid coupling(FeS)framework,which considers the influence of fracture properties and geostress states,is developed and incorporated into a zero-thickness cohesive element(ZE)based NMM(Co-NMM)for simulating tunnel excavation.Additionally,to simulate coagulation of injected slurry,a bonding repair algorithm is further proposed based on the ZE model.To verify the accuracy of the proposed simulator,a series of simulations about slurry migration in single fractures and fracture networks are numerically reproduced,and the results align well with analytical and laboratory test results.Furthermore,these numerical results show that neglecting the influence of geostress condition can lead to a serious over-estimation of slurry migration range and reinforcement effectiveness.After validations,a series of simulations about tunnel grouting reinforcement and tunnel excavation in fault fracture zones with varying fracture densities under different geostress conditions are conducted.Based on these simula-tions,the influence of geostress conditions and the optimization of grouting schemes are discussed.

关键词： Numerical manifold method(NMM) Grouting reinforcement Geostress condition Fault fracture zone Tunnel excavation

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Plants affect the horizontal transmission of a new densovirus infecting the green peach aphid Myzus persicae by modulating honeydew production

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Insect Science 2024年第1期31卷 236-254页

作者： Ya Guo Yani Zhao Yang Yang Yahong Zhang Yuying Li Honggang Tian Tong-Xian liu zhaofei Li State Key Laboratory of Crop Stress Biology for Arid Areas Key Laboratory of Northwest Loess Plateau Crop Pest Management of Ministry of AgricultureCollege of Plant ProtectionNorthwest A&F UniversityYanglingChina Institute of Entomology and Institute of Plant Health&Medicine Guizhou UniversityGuiyangChina

In a tritrophic context of plant-insect-entomopathogen,plants play important roles in modulating the interaction of insects and their pathogenic viruses.Currently,the influence of plants on the transmission of insect viruses has been mainly studied on baculoviruses and some RNA viruses,whereas the impact of plants on other insect viruses is largely unknown.Here,we identified a new densovirus infecting the green peach aphid Myzus persicae and tested whether and how host plants influence the transmission of the aphid densovirus.The complete single-stranded DNA genome of the virus,M.persicae densovirus 2,is 5727 nt and contains inverted terminal repeats.Transcription and phylogenetic analysis indicated that the virus was distinct from other a few identified aphid densoviruses.The virus abundance was detected highly in the intestinal tract of aphids,compared with the lower level of it in other tissues including head,embryo,and epidermis.Cabbage and pepper plants had no obvious effect on the vertical transmission and saliva-mediated horizontal transmission of the virus.However,the honeydew-mediated horizontal transmission among aphids highly depended on host plants(65%on cabbages versus 17%on peppers).Although the virus concentration in the honeydew produced by aphids between 2 plants was similar,the honeydew production of the infected aphids reared on peppers was dramatically reduced.Taken together,our results provide evidence that plants influence the horizontal transmission of a new densovirus in an aphid population by modulating honeydew secretion of aphids,suggesting plants may manipulate the spread of an aphid-pathogenic densovirus in nature.

关键词： aphids densovirus host plants MpDV2 Myzus persicae transmission

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Characteristics and main controlling factors of helium resources in the main petroliferous basins of the North China Craton

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Acta Oceanologica Sinica 2024年第2期43卷 23-33页

作者： Zihan Gao Zhi Chen Hongyi He zhaofei liu Chang Lu Hanyu Wang Yili Luo Ying Li Institute of Earthquake Forecasting China Earthquake AdministrationBeijing 100036China College of Geosciences China University of Petroleum-BeijingBeijing 102249China School of Earth Science and Resources China University of Geosciences(Beijing)Beijing 100083China

At present, the main controlling factors of helium accumulation is one of the key scientific problems restricting the exploration and development of helium reservoir. In this paper, based on the calculation results of He generation rate and the geochemical characteristics of the produced gas, both the similarities and differences between natural gas and He resources in the Bohai Bay, Ordos and the surrounding Songliao Basin are compared and analyzed, discussing the main controlling factors of helium resources in the three main petroliferous basins of the North China Craton. It is found that the three basins of Bohai Bay, Ordos and Songliao have similar characteristics of source rocks, reservoirs and cap rocks, that's why their methane resource characteristics are essentially the same. The calculated ~4He generation per cubic metamorphic crystalline basement in the three basins is roughly equivalent, which is consistent with the measured He resources, and it is believed that the ~4He of radiogenic from the crust is the main factor controlling the overall He accumulation in the three basins;there is almost no contribution of the mantle-derived CH_4, which suggests that the transport and uplift of mantle-derived ~3He carried by the present-day magmatic activities along the deep-large faults is not the main reason for the mantle-derived ~3He mixing in the basins. Combined with the results of regional volcanic and geophysical studies,it is concluded that under the background of the destruction of North China Craton, magma intrusion carried a large amount of mantle-derived material and formed basic volcanic rocks in the Bohai Bay Basin and Songliao Basin, which replenished mantle-derived ~3He for the interior of the basins, and that strong seismic activities in and around the basins also promoted the upward migration of mantle source ~3He. This study suggests that the tectonic zone with dense volcanic rocks in the Cenozoic era and a high incidence of historical strong earthquakes history may be a potential area for hel

关键词： Helium Bohai Bay Basin destruction of the North China Craton fault Cenozoic volcanic rocks strong earthquake activity

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Dynamic transcriptome profiles and novel markers in bovine spermatogenesis revealed by single-cell sequencing

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Journal of Integrative Agriculture 2024年第7期23卷 2362-2378页

作者： Yuan Gao Fuxia Bai Qi Zhang Xiaoya An zhaofei Wang Chuzhao Lei Ruihua Dang Key Laboratory of Animal Genetics Breeding and Reproduction of Shaanxi ProvinceCollege of Animal Science and TechnologyNorthwest A&F UniversityYangling 712100China College of Life Sciences Northwestern Polytechnical UniversityXi’an 710072China

Testicular development is an important biological process in male and requires interaction between the male germ cells and somatic cells.However,the mechanisms of testicular development in livestock,particularly in cattle,are poorly understood.Furthermore,cellular heterogeneity hinders the profiling of different cell types at different developmental stages.In this study,we first performed a single-cell transcriptomic study of the bovine testis development during puberty by using 10×genomics single-cell RNA sequencing(scRNA-seq).By collecting the scRNA-seq data from 11,083 cells from prepubertal and pubertal bovine testes,a high-resolution scRNA-seq atlas was described,identifying 9 somatic and 13 spermatogenic clusters.We also distinguished several stage-specific marker genes for bovine germ cells and somatic cells,such as GRAF2 and MORC1 for SSC(spermatogonial stem cells),HJURP and TCF19 for differentiating spermatogonia,ARSE for immature Sertoli,CLEC12B for mature Sertoli,LOC112441470 for Leydig.In conclusion,we have examined the transcription levels and constructed the single-cell developmental maps of germ cells and somatic cells during testicular development in Angus cattle.The datasets provided new insights into spermatogenesis and testicular somatic cell development in cattle.

关键词： scRNA-seq cattle spermatogenesis testis development

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Spatial-temporal patterns of major ion chemistry and its controlling factors in the Manasarovar Basin, Tibet

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Journal of Geographical Sciences 2015年第6期25卷 687-700页

作者： YAO Zhijun WANG Rui liu zhaofei WU Shanshan JIANG Liguang Institute of Geographic Sciences and Natural Resources Research CAS Beijing 100101 China University of Chinese Academy of Sciences Beijing 100049 China

The Manasarovar Basin in southern Tibet, which is considered a holy land in Buddhism, has drawn international academic attention because of its unique geographical environment. In this study, based on actual measurements of major ion concentrations in 43 water samples collected during the years 2005 and 2012, we analyzed systemically the spatialtemporal patterns of water chemistry and its controlling factors in the lake and inflowing rivers. The results reveal that the water in the Manasarovar Basin is slightly alkaline, with a pH ranging between 7.4-7.9. The amounts of total dissolved solids （TDS） in lake and river waters are approximately 325.4 and 88.7 mg/l, respectively, lower than that in most of the surface waters in the Tibetan Plateau. Because of the long-term effect of evaporative crystallization, in the lake, Na^＋ and HCO3^- have the highest concentrations, accounting for 46.8% and 86.8% of the total cation and anion content. However, in the inflowing rivers, the dominant ions are Ca^2＋ and HCO3^-, accounting for 59.6% and 75.4% of the total cation and anion content. The water exchange is insufficient for such a large lake, resulting in a remarkable spatial variation of ion composition. There are several large inflowing rivers on the north side of the lake, in which the ion concentrations are significantly higher than that on the other side of the lake, with a TDS of 468.9 and 254.9 mg/l, respectively. Under the influence of complicated surroundings, the spatial variations in water chemistry are even more significant in the rivers, with upstreams exhibiting a higher ionic content. The molar ratio between （Ca^2＋＋Mg^2＋） and （Na^＋＋K^＋） is much higher than 1.0, revealing that the main source of ions in the waters is carbonate weathering. Although natural processes, such as rock weathering, are the major factors controlling main ion chemistry in the basin, in the future we need to pay more attention to the anthropogenic influence.

关键词： Manasarovar surface water chemistry spatial-temporal distribution rock weathering Tibetan Plateau

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蒙东黑土区坡耕地退化现状分析

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中国水土保持科学(中英文) 2024年

作者：张守昊孙蕾 JAMSHIDI Abdul Hakim 牛勇刘霞 FAN zhaofei 南京林业大学南方现代林业协同创新中心/江苏省水土保持与生态修复重点实验室山东农业大学林学院山东省土壤侵蚀与生态修复重点实验室/国家林业局泰山森林生态站 .School of Forestry and Wildlife Sciences Auburn University

土壤退化严重威胁蒙东黑土区粮食安全与黑土的可持续利用，为理清区域坡耕地退化现状，选择内蒙古莫力达瓦达斡尔族自治旗为研究区，以坡耕地为研究对象，基于最小数据集、序贯高斯模拟和数理统计等方法，探索蒙东黑土区坡耕地退化程度... 详细信息

土壤退化严重威胁蒙东黑土区粮食安全与黑土的可持续利用，为理清区域坡耕地退化现状，选择内蒙古莫力达瓦达斡尔族自治旗为研究区，以坡耕地为研究对象，基于最小数据集、序贯高斯模拟和数理统计等方法，探索蒙东黑土区坡耕地退化程度空间分布及退化形式和主要影响因素。结果表明：1）蒙东黑土区坡耕地退化程度评价最小数据集包括有机质、腐殖质层厚度、水稳性大团聚体、pH、坡度和垄坡角；2）蒙东黑土区坡耕地土壤退化指数分布范围为0.0811-0.7998，轻度退化和中度退化坡耕地共占坡耕地总面积的83%；3）土壤退化指数与腐殖质层厚度的相关性最高（P<0.01），与坡度和垄坡角呈显著正相关关系（P<0.05），坡度和垄坡角的相关系数为0.356（P<0.05）。综上，蒙东黑土区坡耕地退化程度自东北向西南逐渐递增，主要表现为腐殖质层流失和坡耕地面积的缩减，坡度和垄坡角的交互作用可能是退化的主要影响因素。研究结果可为蒙东黑土区坡耕地退化防治提供数据支撑。

关键词：坡度垄坡角腐殖质层厚度土壤退化指数评价指标体系

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谱系的权力——谫论中古谱牒的基本功能及实践

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学术研究 2024年第3期 119-131,178页

作者：范兆飞中山大学历史学系广东广州510275

中古谱牒具有鲜明的“时代格”。唐代柳芳说,“于时有司选举,必稽谱籍,而考其真伪”。门阀子弟的通婚亦是如此。沈约《奏弹王源》不仅是见证六朝门阀阶层内婚制的重要文献,也可据此理解门阀子弟选择通婚对象的具体凭证和过程。近世祖先... 详细信息

中古谱牒具有鲜明的“时代格”。唐代柳芳说,“于时有司选举,必稽谱籍,而考其真伪”。门阀子弟的通婚亦是如此。沈约《奏弹王源》不仅是见证六朝门阀阶层内婚制的重要文献,也可据此理解门阀子弟选择通婚对象的具体凭证和过程。近世祖先的婚宦,成为有司选官或门阀通婚稽考谱籍中最核心的内容。中古谱牒虽已亡佚,但通过辑考传世文献保存的《王氏谱》《百家谱》等残篇断句,可印证近世祖先婚宦是中古谱牒记载的关键内容,而这些内容正是为六朝政府所控制和垄断的知识文化,普通士庶等闲不能寓目,否则就会出现士庶杂婚的“乱象”。北魏孝文帝令六弟娉娶华夏高门,催生崔卢李郑王婚姻集团,也是坚持士庶不婚的政治产物。在这个意义上,六朝隋唐又可称作“谱牒时代”。五代以降,中古谱牒大规模亡佚,并不意味着谱系的意义全然消失。韩琦家族近乎痴狂的追祖行为,就是一个鲜活的例证。中古谱牒的权力是政治性的、社会性的,而近世谱牒的权力则是文化性的、象征性的,后者的意义并非形同虚设。

关键词：中古谱牒谱系祖先婚宦

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Time-dependent safety of lining structures of circular tunnels in weak rock strata

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International Journal of Mining Science and Technology 2022年第2期32卷 323-334页

作者： Baoguo liu Yu Song zhaofei Chu School of Civil Engineering Beijing Jiaotong UniversityBeijing 100044China School of Civil Engineering Wuhan UniversityWuhan 430072China

Following tunnel excavation and lining completion,fractured surrounding rock deforms gradually over time;this results in a time-dependent evolution of the pressure applied to the lining structure by the surrounding rock.Thus,the safety of the tunnel lining in weak strata is strongly correlated with time.In this study,we developed an analytical method for determining the time-dependent pressure in the surrounding rock and lining structure of a circular tunnel under a hydrostatic stress field.Under the proposed method,the stress–strain relationship of the fractured surrounding rock is assumed to conform to that of the Burgers viscoelastic component,and the lining structure is assumed to be an elastomer.Based on these assumptions,the viscoelastic deformation of the surrounding rock,the elastic deformation of the lining structure,and the coordinated deformation between the surrounding rock and lining structure were derived.The proposed analytical method,which employs a time-dependent safety coefficient,was subsequently used to estimate the durability of the lining structure of the Foling Tunnel in China.The derived attenuation curve of the safety coefficient with respect to time can assist engineers in predicting the remaining viable life of the lining structure.Unlike existing analytical methods,the method derived in this study considers the time dependency of the interaction between the surrounding rock and tunnel lining;hence,it is more suitable for the evaluation of lining lifetime.

关键词： Tunnel lining Surrounding rock pressure Rheological characteristics Weak rock strata Time-dependent safety

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冻融循环作用下的花岗岩边坡岩体强度研究

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金属矿山 2024年第2期 255-261页

作者：刘宏张诏飞李兆龙刁虎伊春鹿鸣矿业有限公司黑龙江伊春152500 中铁资源集团勘察设计有限公司河北廊坊065000 河北省非煤矿山岩土工程技术创新中心河北廊坊065000 中钢集团马鞍山矿山研究总院股份有限公司安徽马鞍山243000

以伊春鹿鸣钼矿发育的花岗岩边坡岩体为例,开展不同风化程度的花岗岩岩石样品的冻融循环单轴抗压强度试验和纵波波速试验,得到不同风化程度的花岗岩冻融循环单轴抗压强度和纵波波速损失程度不同,风化程度高的花岗岩冻融系数较低;冻融循... 详细信息

以伊春鹿鸣钼矿发育的花岗岩边坡岩体为例,开展不同风化程度的花岗岩岩石样品的冻融循环单轴抗压强度试验和纵波波速试验,得到不同风化程度的花岗岩冻融循环单轴抗压强度和纵波波速损失程度不同,风化程度高的花岗岩冻融系数较低;冻融循环作用下的花岗岩单轴抗压强度冻融系数与纵波波速损伤变量之间为线性关系,对于不同风化类型的花岗岩,其线性关系高度相近。从边坡稳定性分析的角度出发,提出了2种获取冻融循环花岗岩边坡岩体强度参数的方法,并进行了计算验证。结果显示:采用单轴抗压强度冻融系数直接折减抗剪强度,或采用纵波波速冻融系数折减RMR值后推导抗剪强度,所得结果均可进行边坡稳定性计算;相对来讲,后者计算的安全系数与边坡体实际稳定状态更为接近。

关键词：花岗岩冻融循环单轴抗压强度纵波波速

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低钛涂釉背板玻璃的制备

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材料科学与工程学报 2024年第1期42卷 116-122页

作者：张莉莉李晓东刘肇菲刘新华陈志明安徽工程大学化学与环境工程学院安徽芜湖241000 安徽信义光伏玻璃有限公司安徽芜湖241000 安徽工程大学纺织服装学院安徽芜湖241000

涂釉背板玻璃是光伏组件最重要的封装材料之一,其反射率对光伏组件的发电效率具有重要影响。光伏涂釉背板玻璃的反射涂层是由钛白粉、玻璃粉、调墨油等配制的釉料,经高温钢化处理烧制而成。由于钛白粉的储量有限且价格昂贵,发展低钛涂... 详细信息

涂釉背板玻璃是光伏组件最重要的封装材料之一,其反射率对光伏组件的发电效率具有重要影响。光伏涂釉背板玻璃的反射涂层是由钛白粉、玻璃粉、调墨油等配制的釉料,经高温钢化处理烧制而成。由于钛白粉的储量有限且价格昂贵,发展低钛涂釉背板玻璃是降低光伏组件成本的重要途径之一。据此,本研究用低成本的亚钛粉代替钛白粉烧制低钛涂釉背板玻璃,研究了亚钛粉替代率与背板玻璃反射率之间的关系,考察了低钛涂釉背板玻璃的耐酸、耐碱、耐盐浸、耐水煮性能,发现低钛涂釉背板玻璃具有与原涂釉背板玻璃一样的优异耐候性。

关键词：背板玻璃低钛涂釉反射率耐候性

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