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矿井瞬变电磁透视探测技术响应特征研究与应用

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煤炭学报 2024年第4期49卷 1976-1988页

作者：李毛飞姜志海刘树才童雪瑞陈尚斌高兆丰代琦中国矿业大学资源与地球科学学院江苏徐州221116 天津市水务规划勘测设计有限公司天津300000

针对大采长/超宽工作面内部隐蔽地质异构体常规地球物理探测难的问题,揭示了对侧发射接收的瞬变电磁透视探测电磁响应机制。采用理论研究、数值模拟和实测数据分析相结合的研究方式,对瞬变电磁透视探测技术电磁场扩散特征、数据影响机... 详细信息

针对大采长/超宽工作面内部隐蔽地质异构体常规地球物理探测难的问题,揭示了对侧发射接收的瞬变电磁透视探测电磁响应机制。采用理论研究、数值模拟和实测数据分析相结合的研究方式,对瞬变电磁透视探测技术电磁场扩散特征、数据影响机制以及探测能力进行了详细研究,研究结果表明:受地空边界的影响,全空间长条形发射回线瞬态电磁场扩散与半空间电磁场扩散不同,全空间状态下感应电动势极值长期位于发射线圈中心位置,无法直接沿用地面“烟圈效应”进行处理解释;对侧发射接收的瞬变电磁透视早期数据主要受一次磁场的影响,具有较高的左右低阻异常分辨能力和探测能力,晚期数据与同侧发射接收数据产生机制相同,为发射线圈附近产生的二次场相互感应扩散形成,其分辨能力和探测能力相对较弱;相较于同侧发射接收的瞬变电磁法,对侧发射接收的瞬变电磁透视技术结合早晚期数据,可以很好的区分低阻异常体相对于发射线圈和接收点的空间位置;低阻异常体越靠近发射线圈,对侧接收的早期数据受到的影响越大,晚期数据影响时间段有所增加,但影响程度越小,越靠近接收点所在巷道,其影响特征相反,以此可以粗略判断低阻异常体沿工作面切向的位置。早晚期数据相结合的瞬变电磁透视探测技术,能更加精细地解译工作面内部及附近隐蔽突水地质异构体的空间信息。

关键词：瞬变电磁透视大采长工作面一次磁场感应磁场水害防治

AN ADAPTIVE CONTROL STRATEGY FOR PROPER MESH DISTRI-BUTION IN LARGE EDDY SIMULATION

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Journal of Hydrodynamics 2010年第6期22卷 865-870页

作者： ZHANG Bin WANG Tong GU Chuan-gang dai Zheng-yuan Key Laboratory for Power Machinery and Engineering of Ministry of Education Shanghai Jiao Tong University Shanghai 200240 China trane＇s Asia-Pacific Research Center Shanghai 200001 China

The Filtering Grid Scale （FGS） of sub-grid scale models does not match with the theoretical Proper FGS （PFGS） because of the improper mesh. Therefore, proper Large Eddy Simulation （LES） Mesh is very decisive for better results and more economical cost. In this work, the purpose is to provide an adaptive control strategy for proper LES mesh with turbulence theory and CFD methods. A new expression of PFGS is proposed on the basis of -5/3 law of inertial sub-range and the proper mesh of LES can be built directly from the adjustment of RANS mesh. A benchmark of the backward facing step flow at Re = 5147 is provided for application and verification. There are three kinds of mesh sizes, including the RANS mesh, lam （LES of adaptive-control mesh）, LFM （LES of fine mesh）, employed here. The grid number of lam is smaller than those of LFM evidently, and the results of lam are in a good agreement with those of DNS and experiments. It is revealed that the results of lam are very close to those of LFM. The conclusions provide positive evidences for the novel strategy.

关键词： Large Eddy Simulation (LES) Proper Filtering Grid Scale (PFGS) turbulence -5/3 law adaptive control

Kriging-based reliability analysis of the long-term stability of a deep driftconstructed in the Callovo-Oxfordian claystone

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Journal of Rock Mechanics and Geotechnical Engineering 2021年第5期13卷 1033-1046页

作者： Ngoc-Tuyen tran Duc-Phi Do Dashnor Hoxha Minh-Ngoc Vu Gilles Armand Univ.Orléans Univ.ToursINSA CVLLaméEA 7494France Andra R&D Division92298Chatenay-MalabryFrance

Callovo-Oxfordian(COx)claystone has been considered as a potential host rock for geological radioactive waste disposal in France(Cigéo project).During the exploitation phase(100 years),the stability of drifts(***/alveoli)within the disposal is assured by the liner,which includes two layers:concrete arch segment and compressible *** latter exhibits a significant deformation capacity(about 50%)under low stress(<3 MPa).Although the response of these underground structures can be governed by complex thermo-hydro-mechanical coupling,the creep behavior of COx claystone has been considered as the main factor controlling the increase of stress state in the concrete liner and hence the long-term stability of ***,by focusing only on the purely mechanical behavior,this study aims at investigating the uncertainty effect of the COx claystone time-dependent properties on the stability of an alveolus of Cigéo during the exploitation *** describe the creep behavior of COx claystone,we use Lemaitre’s viscoplastic model with three parameters whose uncertainties are identified from laboratory creep *** the reliability analysis,an extension of a well-known Kriging metamodeling technique is proposed to assess the exceedance probability of acceptable stress in the concrete liner of the *** open-source code Code_Aster is chosen for the direct numerical evaluations of the performance *** Kriging-based reliability analysis elucidates the effect of the uncertainty of COx claystone on the long-term stability of the concrete ***,the role of the compressible material layer between the concrete liner and the host rock is also highlighted.

关键词： Reliability analysis Kriging metamodeling Time-dependent behavior Compressible material Callovo-Oxfordian(COx)claystone Long-term stability

Enhanced thermoelectric properties of SnSe thin films grown by pulsed laser glancing-angle deposition

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Journal of Materiomics 2017年第4期3卷 293-298页

作者： Chun Hung Suen Dongliang Shi Y.Su Zhi Zhang Cheuk Ho Chan Xiaodan Tang Y.Li Kwok Ho lam Xinxin Chen B.L.Huang X.Y.Zhou Ji-Yan dai Department of Applied Physics The Hong Kong Polytechnic UniversityHung HomKowloonHong KongChina Department of Electrical Engineering The Hong Kong Polytechnic UniversityHung HomKowloonHong KongChina Department of Mechanical and Aerospace Engineering The Hong Kong University of Science and TechnologyClear Water BayKowloonHong KongChina College of Physics Chongqing UniversityChongqing 401331China

SnSe single crystals have been demonstrated to possess excellent thermoelectric *** this work,we demonstrate a grain size control method in growing nanocrystalline SnSe thin films through a glancing angle pulsed-laser deposition *** characterization reveals that the SnSe film deposited at a normal angle has a preferred orientation along a axis,while by contrast,the SnSe film deposited at an 80glancing angle develops a nanopillar structure with the growth direction towards the incident atomic *** glancing angle deposition greatly reduces the grain size of the thin film due to a shadowing effect to the adatoms,resulting in significantly increased power factor for more than 100%.The maximum Seebeck coefficient and power factor are 498.5 mV=K and 18.5 mWcm^(-1)K^(-2),*** enhancement of thermoelectric property can be attributed to the potential barrier scattering at grain boundaries owing to the reduced grain size and increased grain boundaries in the *** this enhanced power factor,and considering the fact that the nanopillar structure should have much lower thermal conductivity than a plain film,the zT value of such made SnSe film could be significantly larger than the corresponding single crystal film,making it a good candidate for thin film-based thermoelectric device.

关键词： Thermoelectric SnSe Glancing angle Potential barrier scattering

Investigation of Polymorphisms in Coding Region of OsHKT1in Relation to Salinity in Rice

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Rice science 2016年第6期23卷 334-338页

作者： pham quynh-hoa tran xuan-an nguyen thi-nha-trang tran thi-thuy-anh hoang hai-yen nguyen thi-hong-van tang thi-hanh do thi-phuc Faculty of Biology VNU University of ScienceHanoi334 Nguyen TraiThanh XuanHanoiVietnam Faculty of Agronomy Vietnam National University of AgricultureNgo Xuan Quang StreetTrau QuyGia LamHanoiVietnam

Rice （Oryza sativa） is sensitive to salinity, but the salt tolerance level differs among cultivars,which might result from natural variations in the genes that are responsible for salt tolerance. High-affinitypotassium transporter （HKTs） has been proven to be involved in salt tolerance in plants. Therefore, wescreened for natural nucleotide polymorphism in the coding sequence of OsHKT1, which encodes the HKTprotein in eight Vietnamese rice cultivars differing in salt tolerance level. In total, seven nucleotidesubstitutions in coding sequence of OsHKT1 were found, including two non-synonymous and five synonymoussubstitutions. Further analysis revealed that these two non-synonymous nucleotide substitutions （G50Tand T1209A） caused changes in amino acids （Gly17Val and Asp403Glu） at signal peptide and the loop ofthe sixth transmembrane domain, respectively. To assess the potential effect of these substitutions on theprotein function, the 3D structure of HKT protein variants was modelled by using PHYRE2 webserver. Theresults showed that no difference was observed when compared those predicted 3D structure of HKTprotein variants with each other. In addition, the codon bias of synonymous substitutions cannot clearlyshow correlation with salt tolerance level. It might be interesting to further investigate the functional roles ofdetected non-synonymous substitutions as it might correlate to salt tolerance in rice.

关键词： polymorphism salt stress OsHKT1 gene rice

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废弃杨木水泥模板纤维特性及纤维板的研究

浙江农林大学学报 2014年第6期31卷 940-946页

作者： PHAM Tuong lam 王新洲邓玉和董葛平 tran Minh Toi CAO Quoc An 南京林业大学材料科学与工程学院江苏南京210037 越南林业大学木材工程学院河内156204

以废弃杨木水泥模板纤维为原料制造纤维板,实现杨木的循环利用。对水泥模板以及分离好的纤维性能进行测试分析,并分别以废弃杨木水泥模板纤维、新鲜杨木纤维为原料制造不同密度的纤维板,讨论原料特性和施胶量对板材性能的影响。研究结... 详细信息

以废弃杨木水泥模板纤维为原料制造纤维板,实现杨木的循环利用。对水泥模板以及分离好的纤维性能进行测试分析,并分别以废弃杨木水泥模板纤维、新鲜杨木纤维为原料制造不同密度的纤维板,讨论原料特性和施胶量对板材性能的影响。研究结果表明:废弃杨木水泥模板表面碳元素含量高于杨木单板表面,而水泥模板表面的氧元素含量较低;废弃杨木水泥模板纤维的堆积密度与新鲜杨木纤维基本相同;当用水泥模板制得的纤维板密度达到0.75 g·cm-3时,板材的力学性能和吸水厚度膨胀率(TS)值均优于其他密度的板材,当施胶量大于等于12.0%时,板材的弹性模量(MOE),静曲强度(MOR),内结合强度(IB)性能均能满足国家标准值的要求。因此,废弃杨木水泥模板完全可以替代普通杨木制造纤维板。

关键词：木材科学与技术废弃杨木水泥模板纤维板物理力学性能施胶量

Effectiveness of bee venom acupuncture for patients suffering from periarthritis humeroscapularis

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中医杂志:英文版 2023年第4期43卷 795-800页

作者： Minh Duc Nguyen Thanh Van tran Quoc Vinh Nguyen Cay Doan Ha Linh Vu Phuong Dang Senior Specialist Clinic National Hospital of AcupunctureHanoi 1000Vietnam Department of Senior Specialist National Hospital of Acupuncture Hanoi 1000Vietnam Department of Senior Specialist Military Institute of Traditional MedicineHanoi 1000Vietnam Department of minimally invasive spine National Hospital of AcupunctureHanoi 1000Vietnam Department of Medicine Dai Nam UniversityHanoi 1000Vietnam

OBJECTIVE:To evaluate the efficacy of bee venom acupuncture in humeroscapularis(PHS)***:One hundred and twenty patients diagnosed with PHS were assigned into four groups:BV1(0.01 mg/kg),BV2(0.005 mg/kg),BV3(0.0025 mg/kg),and control group(vitamin B1 plus novocain 3%injection)with 15 d of *** outcomes of the study including visual analogue scale(VAS)score andβ-endorphin,inflammatory cytokines including interleukin-10(IL-10),IL-1βand tumor necrosis factorα(TNF-α)and shoulder function score were assessed at baseline,after 10 and 15 d of ***:All four groups reported statistically significant improvement in VAS score,motion range,and shoulder function score(Plammatory(IL-10)and decrease of pro-inflammatory(IL-1β,TNF-α)cytokines after treatment(Plammatory cytokines than current therapy used in Vietnam and other groups.

关键词： periarthritis humeroscapularis bee venom acupuncture visual analogue scale range of motion articular shoulder function score inflammatory cytokines

Isolation,identification and artificial inoculation of Ustilago esculenta on Zizania latifolia

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Horticultural Plant Journal 2021年第4期7卷 347-358页

作者： Zhiping Zhang Shengyang Xu Mengqi Kong Haibo dai Yancheng Liu Minmin Miao School of Horticulture and Plant Protection Yangzhou UniversityYangzhou 225009China

The smut Ustilago esculenta is an endophytic fungus that invades Zizania latifolia(Jiaobai)and plays an important role in inducing the host stem to form a swollen *** aims of this study were to investigate isolation,identification and inoculation methods of *** from *** spore suspension culturing method was the best method of isolating ***,and yeast-like fungal strains and septate hyphal strains were *** universal primers ITS1 and ITS4 amplified a ribosomal DNA spacer element from all tested strains,while specific primers for lam16A gene generated a 442 bp product only with septate hyphae *** novo transcriptome assembly results showed that the yeast-like fungal strains did not match Ustilago,and genomic analysis suggested the septate hyphae strains were highly similar to known smut ***,the septate hyphae strains were identified as ***,which indicated that the ITS primers were not species-specific but that lam16A-specific primers can distinguish *** accurately and *** vitro,*** grew quickly on PDA medium at 28°C in ***,an inoculation method was established to produce swollen stems by injecting a spore suspension of *** at OD600=2.5 into the basal culm internode of male Jiaobai.

关键词： Zizania latifolia Ustilago esculenta Spore suspension culturing lam16A gene-specific primers Injection inoculation

A novel approach for synthesis of hierarchical mesoporous Nd2O3 nanomaterials

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Journal of Rare Earths 2017年第7期35卷 677-682页

作者： Le Huu Trinh Dinh Quang Khieu Hoang Thai Long tran Thai Hoa Duong Tuan Quang Nguyen Duc Cuong College of Sciences Hue University 77 Nguyen Hue Hue City Viet Nam Faculty of Hospitality and Tourism Hue University 22 Lam Hoang Hue CityViet Nam College of Education Hue University 34 Le LoL Hue City Viet Nam

A novel route to the fabrication of hierarchical mesoporous Nd_2O_3 nanostructures including nanospheres and nanoporous network was described. Their structure and morphology evolution of the as-synthesized materials were determined by various techniques such as scanning electron microscopy, transmission electron microscopy, high-resolution transmission electron microscopy, X-ray diffraction, energy-dispersive X-ray spectroscopy, Fourier transforminfrared spectra, nitrogen adsorption/desorption isotherm, and a formation mechanism was proposed. The results revealed that the Nd_2O_3 nanospheres had the diameter of 300 nm, which were composed of small primary nanoparticles（NPs） with the size of 10 nm. The nanoporous structure also formed the NPs of ca. 10 nm which were connected with each other to form a three-dimensional（3D） texture. This simple and mild approach to fabricate hierarchical mesoporous Nd_2O_3 nanostructures could be easily scaled up and potentially extended to synthesize other oxide hierarchical structures.

关键词： Nd2O3 hierarchical nanostructures nanospheres nanoporous network rare earths