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Ultimately exposed roof area prediction of bauxite deposit goaf based on macro joint damage

International Journal of Mining Science and Technology 2020年第5期30卷 699-704页

作者： lichun jiang Chao Yang Huazhe Jiao School of Civil Engineering and Transportation South China University of TechnologyGuangzhou 510640China Institute of Safety Science and Engineering South China University of TechnologyGuangzhou 510640China School of Civil Engineering Henan Polytechnic UniversityJiaozuo 454003China

The ultimately exposed roof area(UERA)of goaf is crucial to the safety and economics of underground *** prediction models do not consider the mechanical weakness of rock mass and ignore the influence of the joint damage factor,causing a large predicted exposure area with a high roof falling *** work adopted joint damage factor to derive a new UERA prediction *** relationships between the UERA(S)and the span ratio(m),the density(k)and the diameter of fracture(d)were analysed by the new prediction *** results showed that the exposed area S and the span ratio m have a U-shaped curve *** S decreases with the increase of m and then increases when m is beyond *** exposed roof area S is in an inversely proportional power-law relationship with the fracture surface density k,and the curvature of the S-k relationship curve decreases when d=0.5 and k>7,and S is close to *** is a negative correlation between S and the fracture surface diameter d,the curvature of the S-d curve decreases with the increase of d and k,and the variation rate increases first and then decreases with the increase of d;when k=0.5 and d>9,S is close to *** predicted values of the UERA prediction model are 119.3,112.8,and 114.6 m2 with different joint damage parameters,which are slightly smaller than the actual critical exposure area of a roof(S=120 m2).The case study shows that the alternative prediction model is reasonable and acceptable and provides new theoretical support for the underground mining safety of sedimentary bauxite ore.

关键词： Ultimately exposed roof area Bauxite goaf Prediction model Macro joint damage

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Involvement of VLA-5 and VLA-6 in facilitating endothelium-oriented transmigration of hematopoietic stem/progenitor cells

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吉林大学学报（医学版） 2003年第3期29卷 249-254页

作者： JINLing WANGWei-zhong lichun-jiang Dept.ofClinicalLaboratory China-JapanUnionHospitalJilinUniversityChangchun130031China CentralLabaratory China-JapanUnionHospitalJilinUniversity InstituteofEnvironmentalStudies GraduateSchoolofFrontierSciencetheUniversityofTokyoHongo7-3-1Bunkyo-kuTokyoJapan

目的 :研究 VLA- 5及 VLA- 6是否参与内皮细胞促进的造血干 /祖细胞定向移行。方法 :对纯化人 CD34+ 细胞进行体外移行及阻断实验 ,观察其穿移覆盖人脐静脉内皮细胞 ( HUVECs)滤膜的能力。应用四色荧光活化流式细胞术 ( FACS)检测 CD34... 详细信息

目的 :研究 VLA- 5及 VLA- 6是否参与内皮细胞促进的造血干 /祖细胞定向移行。方法 :对纯化人 CD34+ 细胞进行体外移行及阻断实验 ,观察其穿移覆盖人脐静脉内皮细胞 ( HUVECs)滤膜的能力。应用四色荧光活化流式细胞术 ( FACS)检测 CD34+细胞其粘附分子及趋化因子受体CXCR- 4的表达谱。结果 :基质由来因子 ( SDF) - 1 α介导的动员外周血 ( m PB)及骨髓 ( BM)来源的CD34+ 细胞穿透覆盖 HUVECs滤膜百分率分别为 ( 5 6.6± 2 0 .1 ) %及 ( 1 5 .6± 1 .8) % ,显著高于其穿移未覆盖 HUVECs滤膜的比率。预先对 CD34+ 细胞进行抗 VLA- 5和 /或 VLA- 6中和抗体处理可消除这一促进效应。此外 ,BM来源的 CD34+细胞其穿移覆盖及未覆盖 HUVECs滤膜的能力均显著低于 m PB CD34+细胞 ,两者间穿移能力的差异与其 VLA- 5及 VLA- 6(而非 VLA- 4及趋化因子受体 CXCR- 4)抗原表达水平相关。结论 :VLA- 5和 VLA- 6参与 HUVECs促进 HS/PCs穿移能力。

关键词：落户穿内皮移行人脐静脉内皮细胞基质衍生因子-1α 造血干/祖细胞晚期激活抗原-5 晚期激活抗原-6

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Stem taper functions for Betula platyphylla in the Daxing’an Mountains,northeast China

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Journal of Forestry Research 2021年第2期32卷 529-541页

作者： Muhammad Khurram Shahzad Amna Hussain Harold EBurkhart Fengri Li lichun jiang Key Laboratory of Sustainable Forest Ecosystem Management-Ministry of Education School of ForestryNortheast Forestry UniversityHarbin 150040People’s Republic of China Department of Forest Resources and Environmental Conservation(MC 0324) Virginia Tech310 West Campus DriveBlacksburgVA 24061USA

Accurate prediction of stem diameter is an important prerequisite of forest *** this study,an appropriate stem taper function was developed for upper stem diameter estimation of white birch(Betula platyphylla Sukaczev)in ten sub-regions of the Daxing’an Mountains,northeast *** commonly used taper functions were assessed using a diameter and height dataset comprising 1344 trees.A first-order continuous-time error structure accounted for the inherent *** segmented model of Max and Burkhart(For Sci 22:283–289,***://***/10.1093/fores tscie nce/22.3.283)and the variable exponent taper function of Kozak(For Chron 80:507–515,***://***/10.5558/tfc80507-4)described the data *** to its lower multicollinearity,the Max and Burkhart(1976)model is recommended for diameter estimation at specific heights along the stem for the ten *** comparison,the Max and Burkhart(1976)model was refitted using nonlinear mixed-effects ***-effects models would be used only when additional upper stem diameter measurements are available for *** in region-specific taper functions were indicated by the method of the non-linear extra sum of ***,the particular taper function should be adjusted accordingly for each sub-region in the Daxing’an Mountains.

关键词： White birch Taper function Multicollinearity Autocorrelation Nonlinear regression

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Characterization and Phylogenetic Implications of the Complete Mitogenomes of Two Species in the Genus Zhangixalus(Anura:Rhacophoridae)

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Asian Herpetological Research 2023年第3期14卷 191-211页

作者： lichun jiang Wanqing SONG Yujia LIU Yujie ZHANG Jingfeng LIU Chunxiu LIU Xiaodong JIA Wei CHEN Ecological Security and Protection Key Laboratory of Sichuan Province Mianyang Normal UniversityMianyang 621000SichuanChina Key Laboratory for Molecular Biology and Biopharmaceutics School of Life Science and TechnologyMianyang Normal UniversityMianyang 621000SichuanChina School of Resources and Environmental Engineering Anhui UniversityHefei 230601AnhuiChina

Mitochondrial genomes(mitogenomes)in frogs are essential for reconstructing the phylogenetic relationships and shedding light on the molecular evolution in these ***,there are only seven complete Rhacophoridae genomes that have been reported to *** this paper,two complete mitogenomes of the Chinese whipping frog(Zhangixalus chenfui)and Emei tree frog(***)were described,each of which was 20520 and 19782 bp in size,and had A+T contents of 64.26%and 63.83%.The two mitogenomes each included two non-coding control region(D-loop,CR),two ribosomal RNA genes(rRNAs),13 protein-coding genes(PCGs),and 22 transfer RNA genes(tRNAs),and it was found that the mitogenome of *** also includes three tandem tRNAMet gene sequences.A typical clover-leaf structure was found for all tRNAs except for tRNASer1(AGN),which showed a reduced DHU *** putative D-loop region contains multiple types of tandem repeats *** of these two mitogenomes showed similar pattern of gene rearrangement(tRNA-Ser-ND6-tRNA-Glu-CytbCR1-ND5-CR2-tRNA-Thr-tRNA-Leu-tRNA-Pro).Additionally,three consecutive tRNAMet genes were found for the first time in ***,a species in the Rhacophoridae *** all phylogenetic analyses,which were based on 13 protein-coding genes from 91 Ranoidea mitogenomes,the same phylogenetic trees were observed using either maximum likelihood or Bayesian *** results suggest that the phylogenetic hypotheses for the Ranoidea(including Rhacophoridae,Mantellidae,Ranidae and Dicroglossidae)derived from these mitogenomic data could provide substantiation for the relationships of(Dicroglossidae(Ranidae,(Mantellidae,Rhacophoridae))),and support the presence of a monophyletic group in four ***,*** and *** were found to cluster on the same branch,indicating that they were more closely related as a *** group may in turn form sister groups with *** and ***,*** is located on the ba

关键词： mitochondrial genome Phylogeny Ranoidea Rhacophoridae Zhangixalus chenfui Z.omeimontis

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High Altitude Frogs (Rana kukonoris) Adopt a Diversified Bethedging Strategy in the Face of Environmental Unpredictability

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Asian Herpetological Research 2018年第1期9卷 43-49页

作者： Wei CHEN Liqing PENG lichun jiang David A.PIKE Christopher R.FRIESEN Gregory BROWN Ecological Security and Protection Key Laboratory of Sichuan Province Mianyang Normal University Department of Biology Rhodes College School of Life and Environmental Sciences University of Sydney

Environmental unpredictability can influence strategies of maternal investment among eggs within a clutch. Models predict that breeding females should adopt a diversified bet-hedging strategy in unpredictable environments, but empirical field evidence from Asia is scarce. Here we tested this hypothesis by exploring spatial patterns in egg size along an altitudinal gradient in a frog species （Rana kukunoris） inhabiting the Tibetan Plateau. Within-clutch variability in egg size increased as the environment became variable （e.g., lower mean monthly temperature and mean monthly rainfall at higher altitudes）, and populations in environments with more unpredictable rainfall produced eggs that were smaller and more variable in size. We provide support for a diversified bet-hedging strategy in high-altitude environments, which experience dynamic weather patterns and therefore are of unpredictable environmental quality. This strategy may be an adaptive response to lower environmental quality and higher unpredictable environmental variance. Such a strategy should increase the likelihood of breeding success and maximize maternal lifetime fitness by producing offspring that are adapted to current environmental conditions. We speculate that in high-altitude environments prone to physical disturbance, breeding females are unable to consistently produce the optimal egg size due to physiological constraints imposed by environmental conditions （e.g., duration of the active season, food availability）. Species and populations whose breeding strategies are adapted to cope with uncertain environmental conditions by adjusting offspring size and therefore quality show a remarkable degree of ability to cope with future climatic changes.

关键词： altitude bet-hedging strategy environmental quality egg size within-clutch variation unpredictable environment

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Body Size but Not Food Size Determined Head Sexual Dimorphism in Rana kukunoris from the Tibetan Plateau

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Asian Herpetological Research 2023年第2期14卷 175-181页

作者： Hongzhou CHEN Haifen QIN Zhenkun ZHAO Jiahong LIAO Yanfang WU Xueyan LIU lichun jiang Buddhi DAYANANDA Wei CHEN School of Resources and Environmental Engineering Anhui UniversityHefei 230601AnhuiChina Key Laboratory for Molecular Biology and Biopharmaceutics School of Life Science and TechnologyMianyang Normal UniversityMianyang 621000SichuanChina School of Agriculture and Food Sciences The University of QueenslandBrisbane QLD 4072Australia

Sexual dimorphism between males and females is a common pattern observed in the natural world and has become one of the main focuses of evolutionary *** head size and shape are important factors that may influence food acquisition,but knowledge about the sexual differences between amphibian head size and shape is relatively ***,intersexual differences in the head size and shape of Rana kukunoris,which is a high-elevation frog from the Qinghai-Tibet Plateau,were *** differences were found in the head shape but not the head size between sexes.A significant correlation was also observed between prey size and head ***,these correlations disappeared when individual body size was controlled,suggesting that body size but not food size was the main factor resulting in intersexual differences in head size/*** results suggested that food competition between sexes did not result in sexual dimorphism of head shape among these frogs.

关键词： amphibians head shape morphometrics Rana Rana kukunoris sexual dimorphism

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Modeling Microibril Angle with Mixed Models for Dahurian Larch

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Chinese Forestry Science and Technology 2012年第3期11卷 57-58页

作者： Li Yaoxiang jiang lichun Li Fengri College of Engineering and Technology Northeast Foresry University College of Forestry Northeast Forestry University

In this study,the sample data was based on 2 790 samples of 9 trees from dahurian larch （Larix gmelinii） plantations located in Qitaihe Forest Bureau in Heilongjiang *** modified Logistic model y = b1 /[1 + exp（b2 x）]+ b3 was selected to modeling microfibril angle from six models based on nonlinear ***,the logistic model was fitted using nonlinear mixed-effect modeling approach based on NLME of S-PLUS *** statistics,such as AIC,BIC, Log Likelihood and Likelihood ratio test were used for model *** results showed that the Logistic model with parameters b1,b2,b3 as mixed effects showed the best *** structures included compound-symmetry structure （CS）,first-order autoregressive correlation structure AR（1）,moving average correlation structure MA（1） and autoregressive-moving average correlation structure[ARMA（1,1）]were incorprated into the best microfibril angle mixed model.[ARMA（1,1）]significantly improved the precision of mixed *** confirmed that the mixed model with calibration of random parameters could provide more accurate and precise ***,the application of mixed model not only showed the mean trends of microfibril angle,but also showed the individual difference based on variance-covariance structure and correlation structure.

关键词： microfibril angle(MFA) nonlinear mixed model dahurian larch correlation structure

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硬质黏土层顶板的铝土矿采空区护顶层安全厚度

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中南大学学报（自然科学版） 2020年第2期51卷 445-452页

作者：姜立春杨超华南理工大学土木与交通学院广东广州510640 华南理工大学安全科学与工程研究所广东广州510640

为了实现沉积型地下铝土矿安全开采,在构建护顶层力学模型的基础上,建立力学性质劣化的护顶层安全厚度的计算公式,分析不同跨度比、暴露面积及软化系数条件下护顶层安全厚度的变化趋势。研究结果表明:矿体护顶层结构参数影响安全厚度,... 详细信息

为了实现沉积型地下铝土矿安全开采,在构建护顶层力学模型的基础上,建立力学性质劣化的护顶层安全厚度的计算公式,分析不同跨度比、暴露面积及软化系数条件下护顶层安全厚度的变化趋势。研究结果表明:矿体护顶层结构参数影响安全厚度,安全厚度hs与跨度比呈负相关;随着跨度比增大,安全厚度降低;安全厚度hs与暴露面积呈正相关,随着暴露面积增大,安全厚度增长速率变缓;护顶层软化程度越高,护顶层的安全厚度hs增长越快。工程实例计算结果表明本文公式是合理可靠的。

关键词：铝土矿采空区硬质黏土矿护顶层安全厚度软化系数

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基于损伤模态识别法的复杂采空区群中薄弱单元甄别

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哈尔滨工业大学学报 2023年第7期55卷 87-96,106页

作者：姜立春邵凡华南理工大学土木与交通学院广州510640 华南理工大学安全科学与工程研究所广州510640

为甄别复杂采空区群中的薄弱单元,以某地下石灰石矿山采空区群为工程实例,通过构建离散振动力学模型,和应变改变量相关影响因素分析,创新地提出薄弱单元损伤模态识别法,给出甄别流程,并从算例计算和工程实际应用两方面验证其可靠性。研... 详细信息

为甄别复杂采空区群中的薄弱单元,以某地下石灰石矿山采空区群为工程实例,通过构建离散振动力学模型,和应变改变量相关影响因素分析,创新地提出薄弱单元损伤模态识别法,给出甄别流程,并从算例计算和工程实际应用两方面验证其可靠性。研究结果表明:自振频率和应变模态的甄别指标能准确识别采空区群中的薄弱单元;单体和双体单元损伤都会使采空区群的自振频率甄别指标I_(M)(k)值大于0,损伤区域的应变模态甄别指标I_(N)(x)值会明显出现凸起,随着损伤程度增大,I_(M)(k)值和I_(N)(x)峰值越来越大;仅顶板B1损伤时,高阶I_(M)(k)比低阶更灵敏反映损伤变化程度,第四阶指标识别效果更优;仅矿柱Z6损伤时,第二、四阶I_(M)(k)识别效果更优;B1和Z6共同损伤时,I_(M)(k)对B1损伤程度变化较于Z6更为敏感,第二阶I_(M)(k)识别效果更佳。研究成果为地下采空区群安全定量评估开辟了一条新方向。

关键词：离散振动力学模型法薄弱单元甄别自振频率应变模态

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不均匀分布点状矿柱承载条件下顶板最小安全厚度

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中南大学学报（自然科学版） 2022年第11期53卷 4381-4391页

作者：姜立春卞浩然华南理工大学土木与交通学院广东广州510640 华南理工大学安全科学与工程研究所广东广州510640

为研究不均匀分布点状矿柱承载条件下顶板最小安全厚度,在某省32个地下矿现场调研的基础上,以某地下采空区顶板为对象,根据矿柱位置,将顶板分为行间顶板、列间顶板、行列间顶板等3类,分别构建不同支撑条件下顶板力学模型,推导其应力分... 详细信息

为研究不均匀分布点状矿柱承载条件下顶板最小安全厚度,在某省32个地下矿现场调研的基础上,以某地下采空区顶板为对象,根据矿柱位置,将顶板分为行间顶板、列间顶板、行列间顶板等3类,分别构建不同支撑条件下顶板力学模型,推导其应力分量表达式;考虑节理存在对岩体力学性质的劣化作用,建立力学性质劣化的顶板最小安全厚度的计算公式,分析不同跨度比、暴露面积及节理特征顶板最小安全厚度的变化趋势。研究结果表明:空区顶板结构参数影响最小安全厚度,其他条件不变时,跨度比m=1为最小安全厚度极小值点;总体趋势为随着跨度比增大,最小安全厚度降低;最小安全厚度与暴露面积呈正相关,随着暴露面积增大,最小安全厚度增长速率变缓;空区结构参数一定时,顶板岩体节理密度越大,节理面直径越大,顶板最小安全厚度增长越快。数值模拟结果和工程实例验证了理论计算结果的合理性,为地下房柱法矿山安全开采提供理论支撑。

关键词：采空区不均匀分布点状矿柱群顶板最小安全厚度

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