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Model tests on interaction between soil and geosynthetics subjected to localized subsidence in landfills

Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2012年第6期13卷 433-444页

作者： Bin ZHU deng GAO jun-chao LI Yun-min CHEN MOE Key Laboratory of Soft Soils and Geoenvironmental Engineering Department of Civil EngineeringZhejiang UniversityHangzhou 310058China

In a landfill, excessive tensile strains or failure of the liner system due to localized subsidence underneath the geosynthetic liner, is a concern in design and operation of the landfill. The localized subsidence can be commonly withstood by reinforcements such as geogrids. A total of nine model tests were carried out to study the influence of soil arching in overburden sandy soil on the geosynthetics and the interaction between the soil and the geosynthetics. The localized subsidence was modeled by a strip trapdoor under the geosynthetic reinforcements. The reinforcement includes several layers of polyvinylchlorid （PVC） membrane or both PVC membrane and a compacted clay layer. Test results show that the vertical soil pressure acting on the geosynthetics within the subsidence zone is strongly related to the deflection of the geosynthefics. The soil pressure acting on the deflected geosynthetics will decrease to a minimum value with respect to its deflection if the final deflection is large enough, and this minimum value is almost independent of the overburden height. Otherwise, the deflection of geosynthetics cannot result in a full degree of soil arching, and the soil pressure within the subsidence zone increases with the increase of overburden height. Deflections and strains of the geosynthetics obviously decrease with the increase of their tensile stiffness. The presence of a compacted clay layer buffer can therefore reduce both deflections and strains of the geosynthetics. Finally, a composite liner structure is recommended for landfills to withstand the localized subsidences.

关键词： Landfill Soil arching Trapdoor Model test Geosynthetics

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Three-Component Synthesis of 2-Heteroaryl-3-hydroxybenzo[b]- thiophenes under Transition-Metal-Free Conditions

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Chinese Journal of Chemistry 2021年第9期39卷 2483-2488页

作者： Dahan Wang Fuhong Xiao Feng Zhang Guo-jun deng Key Laboratory for Green Organic Synthesis and Application of Hunan Province Key Laboratory of Environmentally Friendly Chemistry and Application of Ministry of EducationCollege of ChemistryXiangtan UniversityXiangtanHunan 411105China Guangdong Provincial Key Laboratory of Luminescence from Molecular Aggregates South China University of TechnologyGuangzhouGuangdong 510640China

A convenient synthetic route to 2-heteroaryl-3-hydroxybenzo[b]thiophene derivatives via K_(2)CO_(3)-promoted multicomponent cycliza-tion between o-halogenated benzaldehyde,2-methylquinolines and sulfur powder has been *** reaction is performed smoothly under simple conditions to give the corresponding products in moderate to good *** resultant 3-hydroxybenzo[b]thiophenes have been proved to be versatile building blocks in a range of transition-metal-catalyzed cross-coupling reactions.

关键词： Benzothiophenes Transition-metal-free C-H activation Sulfur Multicomponent reactions

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Proton radioactivity within the generalized liquid drop model with various versions of proximity potentials

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Communications in Theoretical Physics 2021年第6期73卷 102-109页

作者： Yu-Qi Xin jun-Gang deng Hong-Fei Zhang School of Nuclear Science and Technology Lanzhou University730000 LanzhouChina

In the present work,we systematically investigate the proton radioactivity half-lives of spherical proton emitters adopting a generalized liquid drop model(GLDM)with 16 different proximity potentials,of which the proximity potential Prox.77-13 gives the closest results to the experimental *** with the previous conclusion that the GLDM with proximity potential Prox.77-13 can also best describeαdecay half-lives,which makes the model more uniform and ***,we use the proximity potential Prox.77-13 in GLDM to predict the proton radioactivity half-lives of 14 spherical proton emitters that are allowed energetically but not yet observed experimentally or specifically ***,we research the Geiger-Nuttall law for proton *** results reveal that the Geiger-Nuttall law can also be well used to study the proton radioactivity half-lives of isotopes with the same orbital angular momentum l.

关键词： spherical proton emitter GLDM proximity energy Geiger-Nuttall law

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Fabrication of multi-shell coated silicon nanoparticles via in-situ electroless deposition as high performance anodes for lithium ion batteries

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Journal of Energy Chemistry 2020年第9期29卷 160-168,I0005页

作者： Wen-Feng Ren jun-Tao Li Shao-Jian Zhang Ai-Ling Lin you-Hu Chen Zhen-Guang Gao Yao Zhou Li deng Ling Huang Shi-Gang Sun State Key Laboratory of Physical Chemistry of Solid Surfaces iChEM(Collaborative Innovation Center of Chemistry for Energy Materials)College of Chemistry and Chemical EngineeringXiamen UniversityXiamen 361005FujianChina College of Energy Xiamen UniversityXiamen 361005FujianChina

Si-based materials have been extensively studied because of their high theoretical capacity,low working potential,and abundant reserves,but serious initial irreversible capacity loss and poor cyclic performance resulting from large volume change of Si during lithiation and delithiation processes restrict their widespread ***,we report the preparation of multi-shell coated Si(DS-Si)nanocomposites by in-situ electroless deposition method using Si granules as the active materials and copper sulfate as Cu *** ratio of Si and Cu was readily tuned by varying the concentration of copper *** multi-shell(Cu@CuxSi/SiO2)coating on Si surface promotes the formation of robust and dense SEI films and the transportation of ***,the obtained DS-Si composites exhibit an initial coulombic efficiency of 86.2%,a capacity of 1636 mAh g^-1 after 100 discharge-charge cycles at 840 mA g^-1,and an average charge capacity of 1493 mAh g^-1 at 4200 mA g^-*** study provides a low-cost and large-scale approach to the preparation of nanostructured Si-metal composites anodes with good electrochemical performance for lithium ion batteries.

关键词： Silicon nanoparticles Multi-shell coating Electroless deposition Anode materials Lithium ion batteries

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Role of inducible nitric oxide synthase expression in aberrant crypt foci-adenoma-carcinoma sequence

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World Journal of Gastroenterology 2003年第6期9卷 1246-1250页

作者： Mei-Hua Xu Chang-Sheng deng you-Qing Zhu jun Lin Department of Gastroenterology,Zhongnan Hospital,Wuhan University,Wuhan 430071,Hubei Province China Department of Gastroenterology Zhongnan Hospital Wuhan University Wuhan 430071 Hubei Province China. xmh-11@***

AIM: To investigate the expression of inducible nitric oxidesynthase (iNOS) in aberrant crypt foci (ACF) -adenomacarcinoma sequence and its relation with tumor cellapoptosis, proliferation and angiogenesis.METHODS: The expression of iNOS, proliferating cellnuclear antigen (PCNA) and microvessel density (MVD) indifferent stages of colorectal cancer were studied by immunohistochemical method from 30 normal tissues, 30nonhyperplastic ACF, 30 hyperplastic ACF, 30 dysplastic ACF,30 adenomas and 60 carcinomas. The apoptotic cells were detected by terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling (TUNEL) method using an Apop Tag in situ detection kit.RESULTS: The immunoreactivity of iNOS significantly increased in the transition from hyperplastic ACF to dysplastic ACF. This transition was associated with a significant decrease in the apoptotic index (AI) (0.73+0.37 vs0.61±0.35, P＜0.05)and significant increases in the PCNA labeling index (LI)(27.3+2.80 vs 40.3+3.11, P＜0.01) and microvessel density (MVD) (55±11.5 vs 70±13.2, P＜0.01). The expression of iNOS was in low levels and positively correlated with PCNALI (r=0.812, P＜0.01) and MVD (r=0.863, P＜0.01) during transition from normal mucosa to nonhyperplastic ACF and hyperplastic ACF. The expression of iNOS was in high levels and positively correlated with AI (r=0.901, P＜0.01) after transition from hyperplastic ACF to dysplastic ACF, adenoma and carcinoma.CONCLUSION: The results suggest that the transition from hyperplastic ACF to dysplastic ACF may be a crucial step in the ACF-adenoma-carcinoma sequence, in which iNOS plays an important role by regulating tumor cell apoptosis,proliferation and angiogenesis.

关键词：一氧化氮合酶肿瘤发生学增殖细胞核抗原微血管密度

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Eco-chemical mechanisms govern phytoplankton emissions of dimethylsulfide in global surface waters

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National Science Review 2021年第2期8卷 43-50页

作者： Xuwei deng jun Chen Lars-Anders Hansson Xia Zhao Ping Xie Donghu Experimental Station of Lake Ecosystems State Key Laboratory of Freshwater Ecology and Biotechnology of ChinaInstitute of HydrobiologyChinese Academy of Sciences Department of Biology/Aquatic Ecology Lund University State Key Laboratory of Vegetation and Environmental Change Institute of BotanyChinese Academy of Sciences Institute for Ecological Research and Pollution Control of Plateau Lakes School of Ecology and Environmental ScienceYunnan University

The anti-greenhouse gas dimethylsulfide(DMS) is mainly emitted by algae and accounts for more than half of the total natural flux of gaseous sulfur to the atmosphere, strongly reducing the solar radiation and thereby the temperature on Earth. However, the relationship between phytoplankton biomass and DMS emissions is debated and inconclusive. Our study presents field observations from 100 freshwater lakes, in concert with data of global ocean DMS emissions, showing that DMS and algal biomass show a hump-shaped relationship, i.e. DMS emissions to the atmosphere increase up to a p H of about 8.1 but, at higher p H, DMS concentrations decline, likely mainly due to decomposition. Our findings from lake and ocean ecosystems worldwide were corroborated in experimental studies. This novel finding allows assessments of more accurate global patterns of DMS emissions and advances our knowledge on the negative feedback regulation of phytoplankton-driven DMS emissions on climate.

关键词： phytoplankton lake ecosystem biological regulation of global climate dimethylsulfide global surface oceans

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Analysis of Deep Convective Towers in a Southwest-Vortex Rainstorm Event

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Journal of Tropical Meteorology 2021年第2期27卷 177-190页

作者： ZHAI Dan-hua KONG Fan-you DAI Ze-jun GAO Song deng Cheng-zhi ZHANG Yong Chongqing Meteorological Observatory Chongqing 401147 China Center for Analysis and Prediction of Storms University of OklahomaNorman 73072 USA Hunan Meteorological Observatory Changsha 410118 China Chongqing Institute of Meteorological Sciences Chongqing 401147 China

The structure and organization of the extreme-rain-producing deep convection towers and their roles in the formation of a southwest vortex(SWV)event are studied using the intensified surface rainfall observations,weather radar data and numerical simulations from a high-resolution convection-allowing *** deep convection towers occurred prior to the emergence of SWV and throughout its onset and development *** largely resemble the vortical hot tower(VHT)commonly seen in typhoons or hurricanes and are thus considered as a special type of VHT(sVHT).Each sVHT presented a vorticity dipole structure,with the upward motion not superpose the positive vorticity.A positive feedback process in the SWV helped the organization of sVHTs,which in turn strengthened the initial disturbance and development of *** meso-γ-scale large-value areas of positive relative vorticity in the mid-toupper troposphere were largely induced by the diabatic heating and *** strong mid-level convergence was attributed to the mid-level vortex *** low-level vortex intensification was mainly due to low-level convergence and the stretching of upward *** meso-α-scale large-value areas of positive relative vorticity in the low-level could expand up to about 400 hPa,and gradually weakened with time and height due to the decaying low-level convergence and vertical stretching in the matured *** the SWV matured,two secondary circulations were formed,with a weaker mean radial inflow than the outflow and elevated to 300-400 hPa.

关键词： southwest vortex deep convective towers diabatic heating secondary circulations heavy rain

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Texture and inhibitor features of grain-oriented pure iron produced by different cold-rolling processes

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Journal of Iron and Steel Research International 2018年第10期25卷 1026-1032页

作者： Jian-jun deng Hai-jun Wang Zhe Rong Li Xiang Sheng-tao Qiu Yong Gan National Engineering Research Center of Continuous Casting Technology Central Iron and Steel Research Institute Beijing 100081 China Wuyang Iron and Steel Co. Ltd. Hebei Iron and Steel Group Wuyang 462400 Hebei China School of Metallurgical Engineering Anhui University of Technology Ma'anshan 243032 Anhui China

To promote the manufacture of grain-oriented pure iron, the texture and inhibitor features of two samples A and B produced by different cold-rolling processes were studied by optical microscopy, X-ray diffraction, and transmission electron microscopy. The results showed that a higher content of inhibitor elements directly resulted in a greater number of fine inhibitors, which exhibited strong inhibitory ability, leading to more fine precipitates of appropriate size effectively inhibiting the growth of primary grains in decarburized bands （sheets） during the single-stage cold-rolling process. The formation of the component with { 110}〈001〉 Goss orientation was greatly suppressed in the stage of primary recrystallization, and this component could hardly be observed in the decarburized band; by contrast, the {411 }〈148〉-oriented grains grew. During the process of high-temperature annealing, abnormal growth occurred and secondary recrystallized grains （Goss orientation） merged with other matrix grains such as { 111 }〈112〉 and {411 }〈148〉. The magnetic induction of samples A and B at 800 Aim was 1.939 T and 1.996 T, respectively.

关键词： Grain-oriented pure iron Microstructure Texture Inhibitor Cold rolling

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A high-Nb-TiAl alloy with ultrafine-grained structure fabricated by cryomilling and spark plasma sintering

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Rare Metals 2023年第5期42卷 1678-1685页

作者： Hao deng Yong-Qiang Wei jun Tang Ai-jun Chen Long-Qing Chen Zu-Xi Xia Key Laboratory of Radiation Physics and Technology of Ministry of Education Institute of Nuclear Science and TechnologySichuan UniversityChengdu610064China The Second Research Institute of Civil Aviation Administration of China(CAAC) Chengdu610064China

In this work,an ultrafine-grained high-Nb-TiAl alloy with a nominal composition of Ti-45Al-8Nb-0.2W-0.2B(at%)was prepared by cryomilling and subsequent spark plasma sintering(SPS)*** chemical composition,particle size,morphology and crystallite size of cryomilled powder were *** is found that cryomilling can effectively reduce the particle size and enhance grain *** ingots sintered at 900 and 1000℃ show an equiaxed near-γmicrostructure with grain sizes<700 nm,while the sample sintered at 1100℃exhibits duplex ***,the one sintered at 1000℃ has excellent mechanical properties,whose compression yield strength,fracture strength,bending strength and plastic strain achieve 1310,2174,578 MPa and 16.8%,*** reasons for the effect of cryomilling and the mechanical behavior of sintered ingots were *** is suggested that cryomilling in combination with SPS is an effective way to synthesize high-NbTiAl alloy with ultrafine-grained structure.

关键词： Cryomilling Spark plasma sintering Titanium aluminide Ultrafine-grained structure

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Influence of paeonol on expression of COX-2 and p27 in HT-29 cells

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World Journal of Gastroenterology 2009年第35期15卷 4410-4414页

作者： jun-Mei Ye Tao deng Jian-Bao Zhang Gastroenterology Department Renmin Hospital Wuhan University Wuhan430060 Hubei Province China

AIM： To investigate the effect of paeonol on controlling the proliferation of colorectal cancer cell line HT-29 and to discuss its possible mechanism. METHODS： The inhibitory effect of paeonol on proliferation of HT-29 cells was detected by M-I-I- assay. The results of apoptosis were measured by flow cytometry. Immunocytochemical staining was performed to detect the expression of cyclooxygenase-2 （COX-2） and protein p27 in HT-29 cells treated with paeonol at different concentrations. Reverse transcription-polymerase chain reaction （RT- PCR） was used for mRNA analysis. RESULTS： From the data of both MTT and flow cytometry, we observed that cell proliferation was inhibited by different concentrations of paeonol. By immunocytochemical staining, we found that HT-29 cells treated with paeonol （0.024-1.504 mmol/L） reflected reduced expression of COX-2 and increased expression of p27 in a dose-dependent manner. RT-PCR showed that paeonol down-regulated COX-2 and up-regulated p27 in a dose- and time-dependent manner in HT-29 cells. CONCLUSION： One of the apoptotic mechanisms of paeonol is down-regulation of COX-2. p27 is upregulated simultaneously and plays an important part in controlling cell proliferation and is a crucial factor in the Fas/FasL apoptosis pathway.

关键词： Peaonol HT-29 cell line Cyclooxygenase-2 p27

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