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25篇 您的检索式:作者名="DONG Longjun"
    题名 作者 年代 出处 被引量
1Failure mechanism and coupled static-dynamic loading theory in deep hard rock mining: A review显示文摘Rock failure phenomena,such as rockburst,slabbing(or spalling) and zonal disintegration,related to deep underground excavation of hard rocks are frequently reported and pose a great threat to deep mining.Currently,the explanation for these failure phenomena using existing dynamic or static rock mechanics theory is not straightforward.In this study,new theory and testing method for deep underground rock mass under coupled static-dynamic loading are introduced.Two types of coupled loading modes,i.e.'critical static stress + slight disturbance' and 'elastic static stress + impact disturbance',are proposed,and associated test devices are developed.Rockburst phenomena of hard rocks under coupled static-dynamic loading are successfully reproduced in the laboratory,and the rockburst mechanism and related criteria are demonstrated.The results of true triaxial unloading compression tests on granite and red sandstone indicate that the unloading can induce slabbing when the confining pressure exceeds a certain threshold,and the slabbing failure strength is lower than the shear failure strength according to the conventional Mohr-Column criterion.Numerical results indicate that the rock unloading failure response under different in situ stresses and unloading rates can be characterized by an equivalent strain energy density.In addition,we present a new microseismic source location method without premeasuring the sound wave velocity in rock mass,which can efficiently and accurately locate the rock failure in hard rock mines.Also,a new idea for deep hard rock mining using a non-explosive continuous mining method is briefly introduced.Xibing Li Fengqiang Gong Ming Tao Longjun Dong Kun Du Chunde Ma Zilong Zhou Tubing Yin 2017Journal of Rock Mechanics and Geotechnical Engineering2017,9,4:68
2A Rare Allele of GS2 Enhances Grain Size anc Grain Yield in Rice显示文摘谷物尺寸决定谷物重量并且影响谷物质量。调整谷物尺寸的几主要量的特点 loci (QTL ) 被克隆;然而,我们调整米饭谷物的尺寸的内在的机制的理解仍然保持碎片。这里,我们报导克隆和主导的 QTL 的描述,染色体 2 上的谷物尺寸(GS2 ) 编码调整生长的因素 4,一个 transcriptional 管理者。GS2 本地化到原子核并且可以充当抄写使活跃之物。影响 microRNA 的有约束力的地点的 GS2 的一个稀罕变化, OsmiR396c,原因提高了 GS2/OsGRF4 的表示。GS2 表示的增加导致更大的房间和房间的增加的数字,它因此提高谷物重量和产量。进米饭栽培变种的 GS2/OsGRF4 的这稀罕等位基因的介绍能显著地提高谷物重量和增加谷物产量,用在引起产量很高的米饭变化的可能的应用。Jiang Hu Yuexing Wang Yunxia Fang Longjun Zeng Jie Xu Haiping Yu Zhenyuan Shi Jiangjie Pan Dong Zhang Shujing Kang Li Zhu Guojun Dong Longbiao Guo Dali Zeng Guangheng Zhang Lihong Xie Guosheng Xiong Jiayang Li Qian Qian 2015Molecular Plant2015,8,10:57
3Velocity-Free MS/AE Source Location Method for Three-Dimensional Hole-Containing Structures显示文摘Microseismic/acoustic emission(MS/AE)source localization method is crucial for predicting and controlling of potentially dangerous sources of complex structures.However,the locating errors induced by both the irregular structure and pre-measured velocity are poorly understood in existing methods.To meet the high-accuracy locating requirements in complex three-dimensional hole-containing structures,a velocity-free MS/AE source location method is developed in this paper.It avoids manual repetitive training by using equidistant grid points to search the path,which introduces A*search algorithm and uses grid points to accommodate complex structures with irregular holes.It also takes advantage of the velocity-free source location method.To verify the validity of the proposed method,lead-breaking tests were performed on a cubic concrete test specimen with a size of 10 cm10 cm10 cm.It was cut out into a cylindrical empty space with a size of/6cm10 cm.Based on the arrivals,the classical Geiger method and the proposed method are used to locate lead-breaking sources.Results show that the locating error of the proposed method is 1.20 cm,which is less than 2.02 cm of the Geiger method.Hence,the proposed method can effectively locate sources in the complex three-dimensional structure with holes and achieve higher precision requirements.Longjun Dong Qingchun Hu Xiaojie Tong Youfang Liu 2020Engineering2020,6,7:22
4Implications for rock instability precursors and principal stress direction from rock acoustic experiments显示文摘The characteristics of rock instability precursors and the principal stress direction are very crucial for the prevention of geological disasters.This study investigated the qualitative relationship between rock instability precursors and principal stress direction through wave velocity in rock acoustic emission(AE)experiments.Results show that the wave velocity variation exhibits obvious anisotropic characteristics in 0%–20%and 60%–90%of peak strength due to the differences of stress-induced microcrack types.The amplitude of wave velocity variation is related to the azimuth and position of wave propagation path,which indicates that the principal stress direction can be identified by the anisotropic characteristics of wave velocity variations.Furthermore,the experiments also demonstrate that the AE event rate and wave velocity show quiet and stable variations in the elastic stage of rock samples,while they present a trend of active and unstable variations in the plastic stage.It implies that both the AE event rate and wave velocity are effective monitoring parameters for rock instability.The anisotropic characteristics of the wave velocity variation and AE event rate are beneficial complements for identifying the rock instability precursors and determining the principal stress direction,which provides a new analysis method for stability monitoring in practical rock engineering.Longjun Dong Yongchao Chen Daoyuan Sun Yihan Zhang 2021International Journal of Mining Science and Technology2021,31,5:10
5A DELLA protein complex controls the arbuscular mycorrhizal symbiosis in plants显示文摘Nan Yu Dexian Luo Xiaowei Zhang Junzhong Liu Wanxiao Wang Yue Jin Wentao Dong Jiyun Liu Huan Liu Weibing Yang Longjun Zeng Qun Li Zuhua He Giles E D Oldroyd Ertao Wang 2014Cell Research2014,24,1:9
6Characterization and mapping of a novel mutant sms1 (senescence and male sterility 1) in rice显示文摘Plant senescence plays diverse important roles in development and environmental responses.However,the molecular basis of plant senescence is remained largely unknown.A rice spontaneous mutant with the character of early senescence and male sterility (sms) was found in the breeding line NT10-748.In order to identify the gene SMS1 and the underlying mechanism,we preliminarily analyzed physiological and biochemical phenotypes of the mutant.The mutant contained lower chlorophyll content compared with the wild type control and was severe male sterile with lower pollen viability.Genetic analysis showed that the mutant was controlled by a single recessive gene.By the map-based cloning approach,we fine-mapped SMS1 to a 67 kb region between the markers Z3-4 and Z1-1 on chromosome 8 using 1,074 F2 recessive plants derived from the cross between the mutant sms1 (japonica) × Zhenshan 97 (indica),where no known gene involved in senescence or male sterility has been identified.Therefore the SMS1 gene will be a novel gene that regulates the two developmental processes.The further cloning and functional analysis of the SMS1 gene is under way.Wenyi Yan Shenghai Ye Qingsheng Jin Longjun Zeng Yu Peng Dawei Yan Weibing Yang Donglei Yang Zuhua He Yanjun Dong Xiaoming Zhang 2010Journal of Genetics and Genomics2010,37,1:6
7Genetic analysis of leaffolder resistance in rice显示文摘A double haploid(DH)population,which consists of 120 lines derived from anther culture of a typical indica and japonica hybrid 'CJ06'/'TN1',was used to investigate the genetic basis for rice leaffolder resistance.Using a constructed molecular linkage map,five QTLs for rolled leaves were detected on chromosomes 1,2,3,4,and 8.The positive alleles from CJ06 on chromosomes 3,4,and 8 in-creased the resistance to rice leaffolder,and the alleles from TN1 on chromosomes 1 and 2 also enhanced resistance to leaffolder.The interactions between QTLs were identified and tested,and four conditional interactions were acquired for resistance to rice leaffolder.These loci were located on chromosomes 2,9,10,and 11,respectively.QTL pyramiding indicated that the positive alleles affect resistance to leaffolder.The prospective application of this data in rice breeding was also discussed.Yuchun Rao Guojun Dong Dali Zeng Jiang Hu Longjun Zeng Zhengyu Gao Guanghen Zhang Longbiao Guo Qian Qian 2010Journal of Genetics and Genomics2010,37,5:6
8Quantitative Trait Loci Mapping of Flag-leaf Ligule Length in Rice and Alignment with ZmLG1 Gene显示文摘A doubled haploid(DH) population,which consists of 120 lines derived from anther culture of a typical indica and japonica hybrid 'CJ06'/'TN1',was used in this study.Ligule lengths of flag leaf were investigated for quantitative trait loci(QTL) mapping using the DH population.Five QTLs(qLL-2,qLL-4,qLL-6,qLL-10 and qLL-12) controlling the ligule length(LL) were detected on chromosomes 2,4,6,10 and 12,with the variances explained 11.4%,13.6%,27.8%,22.1% and 11.0%,respectively.Using four known genes of ZmGL1,ZmGL2,ZmGL3 and ZmGL4 in maize from the MaizeGDB,their homologs in rice were aligned and integrated into the existing simple sequence repeats linkage map by in silico mapping.A ZmLG1 homolog gene,OsLG1 encoding a squamosa promoter binding protein,was located between the markers RM255 and RM280,which is just identical to the interval of qLL-4 on the long arm of chromosome 4.The results are beneficial to dissection of the ligule molecular mechanism and the study of cereal evolution.Dali Zeng Jiang Hu Guojun Dong Jian Liu Longjun Zeng Guangheng Zhang Longbiao Guo Yihua Zhou Qian Qian 2009Journal of Integrative Plant Biology2009,51,4:6
9Quantitative Investigation of Tomographic Effects in Abnormal Regions of Complex Structures显示文摘The detection of abnormal regions in complex structures is one of the most challenging targets for underground space engineering.Natural or artificial geologic variations reduce the effectiveness of conventional exploration methods.With the emergence of real-time monitoring,seismic wave velocity tomography allows the detection and imaging of abnormal regions to be accurate,intuitive,and quantitative.Since tomographic results are affected by multiple factors in practical small-scale applications,it is necessary to quantitatively investigate those influences.We adopted an improved three-dimensional(3D)tomography method combining passive acoustic emission acquisition and active ultrasonic measurements.By varying individual parameters(i.e.,prior model,sensor configuration,ray coverage,event distributions,and event location errors),37 comparative tests were conducted.The quantitative impact of different factors was obtained.Synthetic experiments showed that the method could effectively adapt to complex structures.The optimal input parameters based on quantization results can significantly improve the detection reliability in abnormal regions.Longjun Dong Xiaojie Tong Ju Ma 2021Engineering2021,7,7:6
10Beyond Wigner’s Isobaric Multiplet Mass Equation:Effect of Charge-symmetry Breaking Interaction and Coulomb Polarization显示文摘Heisenberg introduced the concept of isospin to describe different charge states of the nucleon,where the proton(p)and neutron(n)are treated as an isospin T=1/2 doublet distinguished by different projections.As one of the most important predictions in nuclear physics.Dong Jianmin Gu Jianzhong Zhang Yuhu Zuo Wei Wang Longjun Yu A.Litvinov Sun Yang 2019IMP & HIRFL Annual Report2019,,1:2
11Acoustic emission source location method and experimental verification for structures containing unknown empty areas显示文摘Acoustic emission(AE)localization plays an important role in the prediction and control of potential hazardous sources in complex structures.However,existing location methods have less discussion on the presence of unknown empty areas.This paper proposes an AE source location method for structures containing unknown empty areas(SUEA).Firstly,this method identifies the shape,size,and location of empty areas in the unknown region by exciting the active AE sources and using the collected AE arrivals.Then,the unknown AE source can be located considering the identified empty areas.The lead break experiments were performed to verify the effectiveness and accuracy of the proposed method.Five specimens were selected containing empty areas with different positions,shapes,and sizes.Results show the average location accuracy of the SUEA increased by 78%compared to the results of the existing method.It can provide a more accurate solution for locating AE sources in complex structures containing unknown empty areas such as tunnels,bridges,railroads,and caves in practical engineering.Longjun Dong Qing Tao Qingchun Hu Sijia Deng Yongchao Chen Qiaomu Luo Xihong Zhang 2022International Journal of Mining Science and Technology2022,32,3:2
12Unascertained measurement classifying model of goaf collapse prediction显示文摘DONG Longjun PENG Gangjian FU Yuhua 2008Journal of Coal Science & Engineering2008,14,2:1
13Implications for identification of principal stress directions from acoustic emission characteristics of granite under biaxial compression experiments显示文摘The rock fracture characteristics and principal stress directions are crucial for prevention of geological disasters.In this study,we carried out biaxial compression tests on cubic granite samples of 100 mm in side length with different intermediate principal stress gradients in combination with acoustic emission(AE)technique.Results show that the fracture characteristics of granite samples change from‘sudden and aggregated’to‘continuous and dispersed’with the increase of the intermediate principal stress.The effect of increasing intermediate principal stress on AE amplitude is not significant,but it increases the proportions of high-frequency AE signals and shear cracks,which in turn increases the possibility of unstable rock failure.The difference of stress in different directions causes the anisotropy of rock fracture and thus leads to the obvious anisotropic characteristics of wave velocity variations.The anisotropy of wave velocity variations with stress difference is probable to identify the principal stress directions.The AE characteristics and the anisotropy of wave velocity variations of granite under two-dimensional stress are not only beneficial complements for rock fracture characteristic and principal stress direction identification,but also can provide a new analysis method for stability monitoring in practical rock engineering.Longjun Dong Yongchao Chen Daoyuan Sun Yihan Zhang Sijia Deng 2023Journal of Rock Mechanics and Geotechnical Engineering2023,15,4:1
14Co-occurrence of genes for antibiotic resistance and arsenic biotransformation in paddy soils显示文摘Paddy soils are potential hotspots of combined contamination with arsenic(As) and antibiotics, which may induce co-selection of antibiotic resistance genes(ARGs) and As biotransformation genes (ABGs), resulting in dissemination of antimicrobial resistance and modification in As biogeochemical cycling. So far, little information is available for these coselection processes and specific patterns between ABGs and ARGs in paddy soils. Here, the16S rRNA amplicon sequencing and high-throughput quantitative PCR and network analysis were employed to investigate the dynamic response of ABGs and ARGs to As stress and manure application. The results showed that As stress increased the abundance of ARGs and mobile genetic elements (MGEs), resulting in dissemination risk of antimicrobial resistance. Manure amendment increased the abundance of ABGs, enhanced As mobilization and methylation in paddy soil, posing risk to food safety. The frequency of the co-occurrence between ABGs and ARGs, the host bacteria carrying both ARGs and ABGs were increased by As or manure treatment, and remarkably boosted in soils amended with both As and manure. Multidrug resistance genes were found to have the preference to be co-selected with ABGs, which was one of the dominant co-occurring ARGs in all treatments, and manure amendment increased the frequency of Macrolide-Lincosamide-Streptogramin B resistance(MLSB) to co-occur with ABGs. Bacillus and Clostridium of Firmicutes are the dominant host bacteria carrying both ABGs and ARGs in paddy soils. This study would extend our understanding on the co-selection between genes for antibiotics and metals, also unveil the hidden environmental effects of combined pollution.Huiling Cui Dong Zhu Longjun Ding YifeiWang Jianqiang Su Guilan Duan Yongguan Zhu 2023Journal of Environmental Sciences2023,,3:1
15Study of fuzzy random reliability model of tailings dam under earthquake action 显示文摘Wang Feiyue Dong Longjun Xu Zhisheng 2011Ap- plied Mechanics and Materials2011,4447,:1
16Unascertained measurement classifying mod- el of goal collapse prediction 显示文摘Dong Longjun Peng Gangjian FU Yuhua BAI Yunfei LIU Youfang 2008Journal of coal science engineering (English edition)2008,12,2:1
17Unascertained measurement classifying model of goaf collapse prediction显示文摘DONG Longjun PENG Gangjian FU Yuhua 2008Chinese Journal of Coal and Engineering2008,12,2:1
18Comparison of two methods in acoustic emission source location using four sensors without measuring sonic speed显示文摘Li Xibing Dong Longjun 2011Sensor Letters2011,9,5:1
19Unascertained measurement classifying model of goaf collapse prediction 显示文摘DONG Longjun PENG Gangjian FU Yuhua 2008Journal of coal science & engineering2008,12,2:1
20Microseismic event waveform classification using CNN-based transfer learning models显示文摘The efficient processing of large amounts of data collected by the microseismic monitoring system(MMS),especially the rapid identification of microseismic events in explosions and noise,is essential for mine disaster prevention.Currently,this work is primarily performed by skilled technicians,which results in severe workloads and inefficiency.In this paper,CNN-based transfer learning combined with computer vision technology was used to achieve automatic recognition and classification of multichannel microseismic signal waveforms.First,data collected by MMS was generated into 6-channel original waveforms based on events.After that,sample data sets of microseismic events,blasts,drillings,and noises were established through manual identification.These datasets were split into training sets and test sets according to a certain proportion,and transfer learning was performed on AlexNet,GoogLeNet,and ResNet50 pre-training network models,respectively.After training and tuning,optimal models were retained and compared with support vector machine classification.Results show that transfer learning models perform well on different test sets.Overall,GoogLeNet performed best,with a recognition accuracy of 99.8%.Finally,the possible effects of the number of training sets and the imbalance of different types of sample data on the accuracy and effectiveness of classification models were discussed.Longjun Dong Hongmei Shu Zheng Tang Xianhang Yan 2023International Journal of Mining Science and Technology2023,33,10:0
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