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Journal of Earth Science 2024年第2期35卷 568-582页

作者： Bocheng Zhang Huiming Tang yibing ning Kun Fang Ding Xia Department of Engineering Geology and Geotechnical Engineering Faculty of EngineeringChina University of GeosciencesWuhan430074China Badong National Observation and Research Station of Geohazards China University of GeosciencesWuhan430074China College of Geological Engineering and Geomatics Chang’an UniversityXi’an710054China

Block-flexure toppling failure is frequently encountered in interbedded anti-inclined rock(IAR)slopes,and seriously threatens the construction of hydropower *** this study,we first investigated the Lean Reservoir area’s geological setting and the Linda landslide’s ***,uniform design and random design were used to design 110 training datasets and 31 testing datasets,***,the toppling response was obtained by using the discrete element ***,support vector regression was used to obtain the influence weights of 21 impact *** results show that the influence weight of the slope angle and rock formation dip angle on the toppling deformation among tertiary impact factors is 25.96%and 17.28%,respectively,which are much greater than the other 19 impact factors within the research *** the primary impact factors,the influence weight is sorted from large to small as slope geometry parameters,joints parameters,and rock mechanics *** parameters,especially the geometric parameters,cannot be ignored when evaluating the stability of IAR *** numerical simulation,it was qualitatively determined that failure surfaces of slopes were controlled by cross joints and that the rocks in the slope toe play a role in preventing slope deformation.

关键词： interbedded anti-inclined slopes block-flexure toppling impact factors numerical simulation support vector regression engineering geology

A stability evaluation method for deep-seated toppling in the upper Lancang river,Southwestern China

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第7期16卷 2388-2410页

作者： yibing ning Huiming Tang Jianbing Peng Yanjun Shen John V.Smith Bocheng Zhang College of Geological Engineering and Geomatics Chang’an UniversityXi’an710054China Academy of Yellow River Sciences of Shaanxi Province Chang’an UniversityXi’an710054China Badong National Observation and Research Station of Geohazards China University of GeosciencesWuhan430074China School of Engineering RMIT UniversityMelbourne3001Australia

Deep-seated toppling in the upper reaches of the Lancang River,southwest China involves deformations exceeding 100 m in *** slope deformation is initiated by river downcutting and evolves distinctive characteristics with a depth of river *** this study,we propose a system for evaluating the stability of deep-seated toppled slopes in different evolutionary *** system contains identification criteria for each evolutionary stage and provides the corresponding stability evaluation *** on the mechanical and kinematic analysis of slope blocks,the specific stage of slope movement can be identified in the field through outcrop mapping,in situ tests,surface displacement monitoring,and adit and borehole *** stability evaluation methods are established based on the limiting equilibrium theory and the strain compatibility between the undisturbed zone and the toppled ***,several sample slopes in different evolution stages have been investigated to verify the applicability and accuracy of the proposed stability evaluation *** results indicate that intense tectonic activity and rapid river incision lead to a maximum principal stress ratio exceeding 10 near the slope surface,thus triggering widespread toppling deformations along the river *** considering the losses of joint cohesion during the further rotation process,the safety factor of the slope drops by 7%e28%.The self-stabilization of toppling deformation can be recognized by the layer symmetry configuration after the free rotation of the deflected *** toppled rock blocks mainly suffer sliding failures beyond the layer symmetry *** factor of safety of the K73 rockslide decreased from 1.17 to 0.87 by considering the development of the potential sliding surface and the toesaturated zone.

关键词： Stability evaluation Deep-seated toppling Evolutionary process Reservoir impoundment Rock slope

人源长双歧杆菌长亚种i772的分离、鉴定及特性研究

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中国食品学报 2024年第1期24卷 102-109页

作者：张栋冯丽莉荀一萍薛玉玲宁一冰王世杰君乐宝乳业集团股份有限公司石家庄050221

分离人源双歧杆菌,对其进行鉴定及特性研究。从健康婴儿粪便中分离得到1株疑似双歧杆菌,对其进行鉴定,分析其益生菌特性和发酵特性。结果显示:1株分离自婴儿粪便样品的菌株被鉴定为长双歧杆菌,命名为长双歧杆菌长亚种i772,研究发现其对2... 详细信息

分离人源双歧杆菌,对其进行鉴定及特性研究。从健康婴儿粪便中分离得到1株疑似双歧杆菌,对其进行鉴定,分析其益生菌特性和发酵特性。结果显示:1株分离自婴儿粪便样品的菌株被鉴定为长双歧杆菌,命名为长双歧杆菌长亚种i772,研究发现其对25种抗生素敏感;在人工模拟消化液试验中存活率为3.22%;在体外干预THP-1细胞试验中其使促炎免疫因子IL-8、TNF-α和TLR4分别比对照组提高了12.71,5.71,12.56倍。在发酵乳制备试验中,在不影响整体喜好度的前提下,添加长双歧杆菌i772显著(P<0.05)提高了发酵乳的黏度和黏聚性。结论:人源长双歧杆菌i772具有耐受人工胃肠液,调节免疫的特点,适于作为益生菌添加于发酵乳中。

关键词：双歧杆菌益生菌发酵乳

秦岭生态地质环境系统本底特征及研究体系初步构想

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地球科学 2024年第6期49卷 2103-2119页

作者：申艳军陈兴彭建兵穆青翼宁奕冰段丰浩师百垒长安大学地质工程与测绘学院陕西西安710054 西安科技大学地质与环境学院陕西西安710054 黄土科学全国重点实验室(筹) 陕西西安710054

生态文明建设已成为关系人民福祉和民族未来的重大战略任务.秦岭作为中国地理分界带、气候分区带和生态屏障带,也是黄河、长江的重要水源涵养地,其生态屏障功能对维系整个中国生态安全至关重要,在我国生态地质格局中占据重要地位.但目前... 详细信息

生态文明建设已成为关系人民福祉和民族未来的重大战略任务.秦岭作为中国地理分界带、气候分区带和生态屏障带,也是黄河、长江的重要水源涵养地,其生态屏障功能对维系整个中国生态安全至关重要,在我国生态地质格局中占据重要地位.但目前,在气候变化和人类活动的影响下,秦岭面临着地质环境多变、生态环境脆弱、地质灾害频发、人地系统不协调等一系列问题,导致秦岭中央生态屏障功能严重受限.生态地质环境作为生态系统载体,是开展秦岭生态保护与可持续发展研究的基础.本文尝试梳理秦岭生态地质环境系统要素组成及本底特征,掌握秦岭生态地质环境系统要素互馈与协同演进关系,明确秦岭生态损害-土水灾害-地质灾害递进演化过程,进而构建秦岭生态地质环境系统研究体系;同时,初步梳理了该领域亟待攻克五大关键科学问题.研究表明:(1)秦岭生态地质环境本底特征要素包括山体、岩体、土体、水体与林体,“五体”整体表现为:山脉西高东低、北陡南缓;构造复杂,岩性多样;土壤西贫瘠,东肥沃;北属黄河水系,南属长江水系,水系西疏东密;植被覆盖率高,植被类型差异东西较南北更为显著.(2)秦岭人地互馈强烈、工程建设活动频繁,导致局地生态损害严重,水土灾害及地质灾害频发.(3)秦岭生态地质环境系统由地质环境子系统、生态环境子系统和灾害环境子系统所组成,三大子系统间相互耦合、相互作用,互馈关系显著.(4)秦岭地质环境-生态环境-灾害环境三大子系统内要素组成多元、要素互馈显著,围绕各子系统要素间的互馈、协同、递进关系研究,剖析人类活动及外界环境对系统干扰劣化影响,构成了秦岭生态地质环境系统研究体系主体内容.(5)秦岭生态地质环境应把握生态绿色发展理念,聚焦生态地质安全和灾害环境系统问题,围绕秦岭林体-土体-岩体-山体-水体协同演化与动态调控机制,通过跨学科、多角度、全方位融合突破相关科学问题.研究以期为秦岭生态地质环境圈层互馈效应、协同演化机制及生态调控技术发展研究提供借鉴.

关键词：秦岭生态地质环境系统本底特征体系构想关键科学问题工程地质

高山冰川区冰碛土形成过程、成土特征及滑坡灾变机制研究进展

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工程地质学报 2024年第3期32卷 947-962页

作者：魏欣申艳军宁奕冰王艳占洁伟李雪婷西安科技大学地质与环境学院西安710054 长安大学地质工程与测绘学院西安710054 长安大学黄土科学全国重点实验室(筹) 西安710054 长安大学陕西省黄河科学研究院西安710054

冰碛土作为冰川搬运、堆积消融后的主要产物,广泛发育于我国环青藏高原边缘高山冰川区。受高海拔山区地形地貌及极端气候的影响,呈现宽级配、强渗透、非均质、无分选及无层理等特征,是诱发高山冰川区冰碛土滑坡地质灾害的主要物质来源... 详细信息

冰碛土作为冰川搬运、堆积消融后的主要产物,广泛发育于我国环青藏高原边缘高山冰川区。受高海拔山区地形地貌及极端气候的影响,呈现宽级配、强渗透、非均质、无分选及无层理等特征,是诱发高山冰川区冰碛土滑坡地质灾害的主要物质来源。系统掌握高山冰川区冰碛土的形成过程及灾变演化特征对于科学认知孕灾机制具有重要现实价值。据此,首先论述了高山冰川区冰川作用及冰碛地貌特征,阐明了冰碛土的演化过程及发育条件,并针对我国环青藏高原边缘高山冰川区冰碛土的分布特征进行分析。其次,总结了冰碛土的相关分类指标,并探讨了不同沉积部位、沉积时间及沉积成因下冰碛土的典型成土特征。最后,梳理了冰碛土滑坡的主要致灾因素及结构特征,并剖析了在极端气候环境下冰碛土滑坡的发育特征及灾变演化过程。研究表明:(1)高山冰川区冰碛土发育主要受冰川冰进及冰退作用控制,在西部高海拔地区、高山系成群分布且气候垂直变化明显区域广泛发育。(2)不同沉积部位及沉积时间分布的冰碛土结构呈现显著区域分异性,主要表现为高海拔冰川源头的现代冰碛土具有结构松散、磨圆度差且层理不发育等特征,而古冰碛土分布海拔跨度大且结构相对致密。(3)不同类型冰碛土边坡结构引发的界面型滑坡破坏模式包括:浅表层冰碛层降/融水蠕滑型、冰水堆积-古冰碛层界面控制型及冰碛层-湖相沉积接触风化型等3类,其内部富冰带的滞水促滑效应是引发冰碛土界面型滑坡灾害的主要诱因。该研究旨在为揭示高山冰川区冰碛土地质特征及滑坡灾变机制提供基础参考。

关键词：冰碛土形成过程发育条件成土特征灾变机制

澜沧江中上游反倾斜坡倾倒变形影响因素敏感性及斜坡易倾倒几何模型研究

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工程地质学报 2024年第3期32卷 1035-1056页

作者：霍秉尧宁奕冰唐辉明彭建兵申艳军马鹏辉长安大学地质工程与测绘学院西安710054 中国地质大学(武汉)工程学院武汉430000 中国地质大学(武汉)湖北巴东地质灾害国家野外站武汉430000 长安大学黄河科学研究院西安710054

倾倒是反倾岩质斜坡常见的失稳类型,其变形破坏受多种因素影响。为探究各类因素对反倾斜坡倾倒变形的影响程度及其对变形模式的控制作用,本文以澜沧江中上游反倾岩质斜坡为研究对象,建立了反倾斜坡倾倒变形影响因素体系,结合离散元数值... 详细信息

倾倒是反倾岩质斜坡常见的失稳类型,其变形破坏受多种因素影响。为探究各类因素对反倾斜坡倾倒变形的影响程度及其对变形模式的控制作用,本文以澜沧江中上游反倾岩质斜坡为研究对象,建立了反倾斜坡倾倒变形影响因素体系,结合离散元数值模拟试验结果及改进灰色关联分析理论,对各类影响因素的敏感性进行了研究。在此基础上,以斜坡几何特征参数为输入,基于支持向量回归(SVR)理论对研究区反倾斜坡倾倒变形易发几何模型进行预测。结果表明:(1)反倾斜坡的几何特征参数敏感性最高,水平构造应力次之,岩体力学参数敏感性最弱。(2)反倾斜坡的变形量与变形深度与上下坡角呈正相关,变形深度与岩层倾角呈正相关,但变形量随岩层倾角的增大先增大后减小。(3)研究区内的反倾斜坡存在4种变形模式:稳定斜坡、潜在变形斜坡、浅层倾倒斜坡及深层倾倒斜坡。(4)在研究区内,岩层倾角小于57°的斜坡总体保持稳定;超过57°有产生浅层倾倒变形的可能;超过63°时有产生深层倾倒的可能;达到81°,岸坡普遍产生倾倒变形。本研究成果可为此类斜坡变形体的野外早期识别与灾害危险性评估提供可靠理论参考。

关键词：反倾斜坡 UDEC 改进灰色关联分析敏感性分析倾倒变形

Unravelling the nature of the active species as well as the Mn doping effect over gamma-Al_(2)O_(3) catalyst for eliminating AsH_(3) and PH_(3)

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Journal of Environmental Sciences 2024年第2期136卷 213-225页

作者： Bowen Xu Jiaxin Qu Xueqian Wang Langlang Wang Yu Pu Ping ning yibing Xie Yixing Ma Qiang Ma Faculty of Environmental Science and Engineering Kunming University of Science and TechnologyKunming 650500China School of Architecture and Civil Engineering Chengdu UniversityChengdu 610106China

To investigate the enhancing effect of Mn on the performance of simultaneous catalytic oxidation of AsH_(3)and PH_(3)by CuO-Al_(2)O_(3)in a reducing atmosphere under micro-oxygen conditions,Cu-Mn modifiedγ-Al_(2)O_(3)catalysts were *** characteristics of the catalysts showed that Mn reduced the crystallinity of the active CuO component,increased the number of oxygen vacancies and acidic sites on the catalyst surface,enhanced the mobility of surface oxygen,and the interaction between copper and manganese promoted the redox cycling ability of the catalysts and improved their oxidation performance,which increased the conversion frequency(TOF)by 2.54×10^(-2)to 3.07×10^(-2)sec^(-1).On the other hand,the introduction of Mn reduced the production of phosphate and As_(2)O_(3)on the catalyst surface by30.96%and 44.9%,which reduced the coverage and inerting of the active sites by phosphate and As_(2)O_(3),resulting in an 8 hr(6 hr)improvement in the stability of PH_(3)(AsH_(3))removal.

关键词： AsH_(3)-PH_(3)removal Oxygen activation Mn doping Stability enhancement

Mineral compositions in breast milk of healthy Chinese lactating women in urban areas and its associated factors

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Chinese Medical Journal 2014年第14期127卷 2643-2648页

作者： Zhao Ai ning yibing Zhang Yumei Yang Xiaoguang Wang Junkuan Li Wenjun Wang Peiyu Peking Univ Dept Nutr & Food Hyg Sch Publ Hlth Hlth Sci Ctr Beijing 100191 Peoples R China Nestle Res Ctr Beijing 100095 Peoples R China Chinese Ctr Dis Control Prevent Natl Inst Nutr & Food Safety Beijing 100050 Peoples R China Nestle Nutr Inst Beijing 100102 Peoples R China

Background Optimal mineral intakes are important for infant growth and development. However, data on mineral compositions of breast milk in Chinese women are scarce, and most were acquired before 1990. The objectives of this study were three-fold：（1） to investigate the mineral compositions of Chinese healthy mothers＇ breast milk in different lactation stages; （2） to explore correlations among mineral concentrations in breast milk; and （3） to explore the associated factors affecting mineral compositions in breast milk. Methods The inductively coupled plasma mass spectrometry （ICP-MS） was used to analyze mineral concentrations in breast-milk of 444 healthy lactating women from three cities in China. A questionnaire was used to survey socio- demographic characteristics and pregnancy history. Food intakes by lactating women were measured using both food frequency questionnaire and one cycle of 24-hour dietary recall. Results Mineral compositions of breast milk varied in different regions. Concentrations of most minerals were higher in the first one or two months of lactation, and then decreased with time, except for magnesium and iron. Inter-mineral correlations existed among several minerals. The calcium-to-phosphorus ratio was above 2：1 in each lactation stage. Women with caesarean section had higher concentration of iodine in the transitional milk （349.9 pg/kg） compared to women with natural delivery （237.5 pg/kg, P〈0.001）. Dietary mineral intakes, supplements, food intake frequencies in the recent 6 months, maternal age and maternal BMI did not show significant correlations with concentrations of milk minerals （all P 〉0.05）. Conclusions Milk minerals decreased with time, and changed most rapidly in the first one or two months of lactation. Caesarean section might affect the iodine level in transitional milk. Chin Med J 2014;127 （14）： 2643-2648

关键词： human breast milk mineral inter-mineral interactions associated factors

Breast milk macronutrient composition and the associated factors in urban Chinese mothers

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Chinese Medical Journal 2014年第9期127卷 1721-1725页

作者： Yang Titi Zhang Yumei ning yibing You Lili Ma Defu Zheng Yingdong Yang Xiaoguang Li Wenjun Wang Junkuan Wang Peiyu Department of Nutrition & Food Hygiene School of Public Health Peking University Health Science Center Beijing 100191 China Nestle Research Center Beijing Beijing 100095 China National Institute for Nutrition and Food Safety Chinese CDCBeijing 100050 China Nestle Nutrition Institute Beijing 100102 China

Background Infancy is a critical period of growth and physiological development,in which breast milk is the best source of *** to western countries,research on breast milk of Chinese population are ***,it is necessary to measure breast milk energy and macronutrient concentrations of healthy urban Chinese mothers at different lactation stages,to expand the database of milk composition of Chinese population,and to examine whether dietary or other maternal factors can affect the levels of macronutrients in breast *** Breast milk of full expression of one side breast from 436 urban Chinese lactating mothers at 5-11 days,12-30 days,31-60 days,61-120 days,and 121-240 days postpartum was obtained at 9：00 *** 11：00 *** energy,lactose,protein,and fat contents were measured.24-hour dietary recall was surveyed,and maternal nutrient intakes were *** Milk composition changed over the course of lactation and large individual variations were *** concentrations were 61.3 kcal/dl for total energy,7.1 g/dl for lactose,0.9 g/dl for protein,and 3.4 g/dl for fat in mature *** of lactation was a strong factor affecting milk *** evidence was found for associations between maternal current dietary intake and milk macronutrient concentration,consistently with prior *** body mass index （BMI） was positively associated with milk fat content,to a greater extent than did dietary *** other maternal characteristics were not significant for milk *** These findings suggest that milk composition is generally weakly associated with maternal factors except for stage of lactation,and is likely to be more susceptible to long-term maternal nutritional status than short-term dietary fluctuation.

关键词： lactation milk composition macronutrients dietary intake body mass index

Autonomous Recommendation of Fault Detection Algorithms for Spacecraft

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IEEE/CAA Journal of Automatica Sinica 2024年第1期11卷 273-275页

作者： Wenbo Li Baoling ning the National Key Laboratory of Science and Technology on Space Intelligent Control Beijing Institute of Control EngineeringBeijing 100094China the School of Data Science and Technology Heilongjiang UniversityHarbin 150001China

Dear Editor, This letter deals with the problem of algorithm recommendation for online fault detection of spacecraft. By transforming the time series data into distributions and introducing a distribution-aware measure, a principal method is designed for quantifying the detectabilities of fault detection algorithms over special datasets.

关键词： fault introducing letter