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Minimum detectable activity for NaI(Tl) airborne γ-ray spectrometry based on Monte Carlo simulation

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Science China(Technological Sciences) 2014年第9期57卷 1840-1845页

作者： gong ChunHui ZENG GuoQiang GE LiangQuan tanG Xiaobin tan ChengJun Department of Nuclear Science and Engineering Nanjing University of Aeronautics and Astronautics College of Nuclear Technology and Automation Engineering Chengdu University of Technology

The determination of the effective minimum detectable activity （MDA） of radionuclides by a detection system plays an im- portant role in environmental radiation monitoring. In this study, the responses of an NaI（TI） airborne γ ray spectrometry （AGRS） system to different radionuclides （137Cs and 131I） were investigated using the Monte Carlo technique. The MDA values were determined under different conditions according to the counting spectra obtained from the Monte Carlo simulation. The equivalent mass thickness method was applied to the Monte Carlo modeling for monitoring ground radiation to reduce sta- tistical uncertainty. The secondary source method was used to monitor both air and ground radiation. A quadratic relationship was found between the MDA and activity concentration. An exponential relationship was found between the MDA and altitude The MDA of a specific radionuclide from external detectors was found to be superior to that obtained from internal detectors under the same conditions. The MDA values in an NaI（Tl） AGRS system under different conditions can be estimated based on the results of this study.

关键词： NaI(TI) airborne γ-ray spectrometry minimum detectable activity Monte Carlo simulation

高压氧可消除高强度间歇冲击微周期训练中的运动性疲劳

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中国组织工程研究 2025年第14期29卷 2979-2988页

作者：裴云祥吴昊首都体育学院北京市100191

背景:高压氧作为新兴的疲劳消除手段之一,在体育领域中得到越来越多的重视和应用。高压氧干预对高强度间歇冲击微周期训练疲劳消除的研究较少。目的:探究高压氧干预对高强度间歇冲击微周期训练运动性疲劳消除效果的影响,并从血液生化指... 详细信息

背景:高压氧作为新兴的疲劳消除手段之一,在体育领域中得到越来越多的重视和应用。高压氧干预对高强度间歇冲击微周期训练疲劳消除的研究较少。目的:探究高压氧干预对高强度间歇冲击微周期训练运动性疲劳消除效果的影响,并从血液生化指标和代谢组学方面进行相应机制研究。方法:在首都体育学院招募20名男性大学生,随机分为对照组(n=10)和高压氧组(n=10),均进行高强度间歇冲击微周期训练,为期2周,共12次,具体训练方案为先以50%HR_(max)的强度热身10 min,再以90%-95%HR_(max)强度蹬车4 min,重复5组,组间休息2.5 min,最后再进行50%HR_(max)强度蹬车30 min。对照组受试者训练后自然恢复,高压氧组受试者训练后进行高压氧恢复,每次干预60 min,压力为131.722 kPa。在试验前、试验中期、试验后1 d和试验后3 d采集血液分析生化指标及代谢组学指标,并进行主观感觉疲劳量表评分,其中氧化应激指标与疲劳监控指标进行Pearson相关性分析。结果与结论:①运动性疲劳指标变化:与训练前相比,对照组训练后血尿酸、肌酸激酶、白细胞介素6和主观感觉疲劳量表评分均有不同程度的上调,而高压氧组在高压氧干预后血尿酸、肌酸激酶、白细胞介素6和主观感觉疲劳量表评分变化不大;组间相比,对照组试验后1 d血尿酸、肌酸激酶和白细胞介素6水平显著高于高压氧组;②氧化应激指标变化:与训练前相比,对照组训练后超氧化物歧化酶活性降低、丙二醛水平升高,而高压氧组在高压氧干预后超氧化物歧化酶活性升高、丙二醛水平降低;③超氧化物歧化酶与血尿酸、白细胞介素6和主观感觉疲劳量表评分呈负相关;丙二醛与白细胞介素6和主观感觉疲劳量表评分呈正相关;④代谢组学指标变化:显著变化的代谢通路是花生四烯酸代谢和氧化磷酸化代谢,富集通路上差异代谢物质有花生四烯酸、前列腺素D2、白三烯D4等。结果表明,高强度间歇冲击微周期训练导致机体发生氧化应激,促进了运动性疲劳的产生;高压氧可以一定程度改善氧化应激水平,以及引起花生四烯酸代谢和氧化磷酸化代谢,从而减少氧化损伤,调节炎症反应,促进组织修复和运动性疲劳消除。

关键词：高压氧高强度间歇冲击微周期运动性疲劳氧化应激代谢组学

Oracle Inequality for Sparse Trace Regression Models with Exponentialβ-mixing Errors

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Acta Mathematica Sinica,English Series 2023年第10期39卷 2031-2053页

作者： Ling PENG Xiang Yong tan pei Wen XIAO Zeinab RIZK Xiao Hui LIU School of Statistics and Data Science Jiangxi University of Finance and EconomicsNanchang 330013P.R.China Key Laboratory of Data Science in Finance and Economics Jiangxi University of Finance and EconomicsNanchang 330013P.R.China

In applications involving,e.g.,panel data,images,genomics microarrays,etc.,trace regression models are useful *** address the high-dimensional issue of these applications,it is common to assume some sparsity *** the case of the parameter matrix being simultaneously low rank and elements-wise sparse,we estimate the parameter matrix through the least-squares approach with the composite penalty combining the nuclear norm and the *** extend the existing analysis of the low-rank trace regression with *** to exponentialβ-mixing *** explicit convergence rate and the asymptotic properties of the proposed estimator are ***,as well as a real data application,are also carried out for illustration.

关键词： Trace regression model low-rank matrix oracle inequality exponentialβ-mixing errors

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Co-delivery of Andrographolide and Notch1-targeted siRNA to Macrophages with Polymer-based Nanocarrier for Enhanced Anti-inflammation

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Chinese Journal of Polymer Science 2018年第12期36卷 1312-1320页

作者： Teng Wu Min tan Heng-Ye gong Yong Wang Xin-Tao shuai PCFM Lab of Ministry of Education School of Materials Science and Engineering Sun Yat-Sen University Guangzhou 510275 China Center of Biomedical Engineering Zhongshan School of Medicine Sun Yat-sen University Guangzhou 510080 China

Chronic inflammatory responses induced by macrophages play a pivotal role in the progression of atherosclerosis. In the present study, a multifunctional nanocarrier based on poly（ethylene glycol）-block-poly（L-aspartic acid） grafted with diethylenetriamine, lysine and cholic acid （PEG-PAsp（DETA）-Lys-CA2） polymer was synthesized for co-delivery of andrographolide and siRNA targeting Notchl gene to alleviate the inflammatory response in macrophages. The nanocarrier exerted low cytotoxicity as well as high performance in drug/siRNA co-delivery. In vitro studies demonstrated the co-delivery of andrographolide and Notchl siRNA not only significantly inhibited lipopolysaccharide （LPS）-activated interleukin-6 （IL-6） and monocytes chemotactic protein 1 （MCP-1） expression as well as blocked nuclear factor-rd3 （NF-rd3） signal activation, but also interfered the Notchl gene expression and increased anti-inflammatory cytokines such as interleukin-10 （IL-10） and arginase-1 expression obviously in macrophages. These results suggested that the combination therapy based on Notchl siRNA and andrographolide co-delivered nanocarrier, i.e. suppressing the expression of proinflammatory cytokines while simultaneously increasing anti-inflammatory factors expression, be a feasible strategy for atherosclerosis treatment.

关键词： Macrophages Anti-inflamatory Andrographolide Notchl siRNA

Cyclic oxidation behavior of Ni_(3)Al-based single crystal alloy IC21

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Rare Metals 2023年第5期42卷 1656-1662页

作者： Tian-Tian Yang Xin Zhou Shu-Suo Li Yan-Ling pei Sheng-Kai gong School of Materials Science and Engineering Beihang UniversityBeijing100191China

In this study,the cyclic oxidation tests of the Ni3Al-based single-crystal super alloy IC21 were carried out at 800,900,950,1000,1050 and 1100℃in *** present study shows that the complex oxide scale on the surface of the alloy is made up of an outer columnar NiO layer,an intermediate mixture of NiO and NiAl2O4layer with a small amount of Mo oxides and an inner continuous layer ofα-Al_(2)O_(3).The cyclic oxidation kinetics curves show that oxidation resistance at 800,900,950,1000 and1050℃seems to follow a similar law and is better than that at 1100℃.The overall weight changes at 1100℃follows a parabolic *** and severe rumpling of the oxide scale are observed on the surface of the alloy at1100℃,revealing the occurrence of disastrous oxidation.

关键词： Ni_(3)Al Thermal cycling Oxidation Microstructure

Regulation of Oxygen Activity by Lattice Confinement over Ni_(x)Mg_(1-x)O Catalysts for Renewable Hydrogen Production

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Engineering 2022年第5期8卷 62-69页

作者： Hao Tian Chunlei pei Sai Chen Yang Wu Zhijian Zhao Jinlong gong Key Laboratory for Green Chemical Technology of Ministry of Education School of Chemical Engineering and TechnologyTianjin UniversityTianjin 300072China Collaborative Innovation Center of Chemical Science and Engineering Tianjin 300072China Joint School of National University of Singapore and Tianjin University International Campus of Tianjin UniversityBinhai New CityFuzhou 350207China

The chemical looping steam reforming(CLSR)of bioethanol is an energy-efficient and carbon-neutral approach of hydrogen *** paper describes the use of a Ni_(x)Mg_(1-x)O solid solution as the oxy-gen carrier(OC)in the CLSR of *** to the regulation effect of Mg^(2+)in Ni_(x)Mg_(1-x)O,a three-stage reaction mechanism of the CLSR process is *** surface oxygen of Ni_(x)Mg_(1-x)O initially causes complete oxidation of the ***,H_(2)O and bulk oxygen confined by Mg^(2+)react with etha-nol to form CH_(3)COO^(*)followed by H_(2) over partially reduced Ni_(x)Mg_(1-x)*** the bulk oxygen is con-sumed,the ethanol steam reforming process is promoted by the metallic nickel in the stage Ⅲ.As a result,Ni_(0.4)Mg_(0.6)O exhibits a high H_(2) selectivity(4.72 mol H_(2) per mole ethanol)with a low steam-to-carbon molar ratio of 1,and remains stable over 30 CLSR *** design of this solid-solution OC pro-vides a versatile strategy for manipulating the chemical looping process.

关键词： Chemical looping Ethanol steam reforming Nickel Hydrogen production Solid solution

Response of nearshore circulation outside Yangtze Estuary to El Nino events

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Water Science and Engineering 2016年第2期9卷 145-154页

作者： Wen-yan Zhang Zheng gong Chang-kuan Zhang Wei tan State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering Hohai University Nanjing 210098 China CCCC Third Harbor Consultants Co. Ltd. Shanghai 210030 China Jiangsu Key Laboratory of Coast Ocean Resources Development and Environment Security Hohai University Nanjing 210098 China

With consideration of the comprehensive effects of runoff from the Yangtze River, East China Sea background circulation, and tidal currents,a regional circulation model, including the Yangtze Estuary, Hangzhou Bay, and adjacent sea areas was established. The 2002/2003 El Ni^no event was chosen for study of the anomalies of circulation outside the Yangtze Estuary. The coastal and ocean current systems of the East China Sea and the current structure outside the Yangtze Estuary were accurately described. The results of vertical circulation analysis basically coincide with those of horizontal circulation analysis, showing that the circulation outside the Yangtze Estuary is mainly affected by the Taiwan warm current, runoff from the Yangtze Estuary, and the tide-induced residual current. The El Ni^no event weakens Yangtze Estuary circulation to a certain degree, and the impacts are more significant in summer than in winter. During the 2002/2003 El Ni^no event, the flux of the Taiwan warm current decreases, and the northward component of the Taiwan warm current decreases by half in February 2003 compared to the previous year. However, its path is relatively stable.

关键词： El Nino Princeton ocean model Yangtze Estuary Circulation Taiwan warm current

Zircon U-Pb age, Trace Element, and Hf Isotopic Compositions of Nordmarkite in the Lizhuang Rare Earth Element Deposit in the Western Margin of the Yangtze Block

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Acta Geologica Sinica(English Edition) 2018年第1期92卷 225-240页

作者： ZHOU Jiayun tan Hongqi gong Daxin ZHU Zhimin LUO Liping Institute of Multipurpose Utilization of Mineral Resources Chinese Academy of Geological Sciences Chengdu 610041

The Mianning-Dechang （MD） rare earth element （REE） belt, located in the northern Kangdian axis （KDA） in the western margin of the Yangtze platform, is one of the most economically significant REE mineral belts in China. REE mineralization is associated with Himalayan carbonatite- alkaline complexes. The Lizhuang nordmarkite occurred in the northern part of the MD REE belt. The majority of zircons from the Lizhuang nordmarkite are characterized by pronounced positive Ce yet slightly negative Eu anomalies and high U/Yb. Moreover, all zircons have stable Hf isotopic compositions with initial 176Hf/177Hf ratios ranging from 0.282739 to 0.282808 and an average value of 0.282773. The negative Lu/Hf and positive till（t） range from -0.98 to -0.94 （average value of -0.96） and from -0.56 to 1.89 （the majority is positive, with an average of 0.66）, respectively. These characteristics indicate that the rock is derived from an enriched mantle and subducted material. LA-ICP-MS analysis of the zircons from the intrusion yields a weighted mean 2~6pb/23SU age of 28.57~0.61Ma. During this period, the tectonic activity in the KDA is not plate subduction but an intraplate tectonic exhibiting fold-thrust and strike-slip behaviors in the western marginal zone of the Yangtze platform （WMYB）. We suggest the possibility of an existing eastward old slab subduction under WMYB combined with a regional tectonic evolution. The Lizhuang nordmarkite may be derived from an enriched mantle beneath the western part of the Yangtze craton, which originated from the remelting of the Tethys subducting slab, because of the Himalayan strike-slip that formed a special type of REE deposit called strike-slip-type REE deposits.

关键词： nordmarkite REE deposit Hf isotopic characteristics of zircon Lizhuang

Copper(Ⅰ) complexes with planar chirality realize efficient circularly polarized electroluminescence

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Science China Chemistry 2023年第8期66卷 2274-2282页

作者： Ao Ying Lisi Zhan Yao tan Xiaosong Cao Chuluo Yang Shaolong gong Department of Chemistry Hubei Key Lab on Organic and Polymeric Optoelectronic MaterialsWuhan UniversityWuhan430072China Shenzhen Key Laboratory of New Display and Storage Materials College of Materials Science and EngineeringShenzhen UniversityShenzhen518060China

Chiral organometallic emitters hold great promise in potential and practical applications of circularly polarized organic lightemitting diodes(CP-OLEDs).However,developing luminescent earth-abundant organometallic complexes concurrently exhibiting circularly polarized luminescence(CPL)and high quantum efficiency remains a formidable *** this study,we introduced a typical planar chiral skeleton of a[2.2]paracyclophane moiety into earth-abundant copper(I)complexes with the goal of realizing efficient CPL and thermally activated delayed fluorescence(TADF)*** pairs of proof-of-theconcept copper(I)enantiomers,R_(p)/S_(p)-MAC^(*)-Cu-CzP and R_(p)/S_(p)-MAC^(*)-Cu-CNCzP,were developed using planar chiral[2.2]paracyclophane-based donor ligands in a carbene-metal-amide(CMA)*** panels of enantiomers not only exhibited significant mirror-image CPL signals but also displayed distinct TADF nature with fast reverse intersystem crossing rates of up to 10^(8)s^(-1).The resultant OLEDs based on the MAC^(*)-Cu-Cz P enantiomers manifested efficient circularly polarized electroluminescence with excellent external quantum efficiencies of 13.2%and ultraslow efficiency roll-off(7.7%at 10,000 nits).This article not only demonstrates one of the best performances for CP-OLEDs based on earth-abundant organometallic complexes but also represents the first example of CP-OLEDs from CMA complexes to our knowledge.

关键词： circularly polarized luminescence(CPL) organic light-emitting diode(OLED) copper(Ⅰ)complex carbene-metal-amide(CMA) thermally activated delayed fluorescence(TADF)

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