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Enhanced thermoelectric composite performance from mesoporous carbon additives in a commercial bi_(0.5)Sb_(1.5)Te_(3) matrix

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Journal of Materials Science & Technology 2021年第35期94卷 175-182页

作者： Seong-Tae Kim Jong Min park Kwi-Il park Sang-Eun Chun Ho Seong lee Pyuck-pa Choi Seonghoon Yi School of Materials Science and Engineering Kyungpook National UniversityDaegu 41566Republic of Korea Department of Materials Science and Engineering Korea Advanced Institute of Science and Technology(KAIST)291 Daehak-roYuseong-guDaejeon 34141Republic of Korea

Composites were prepared,through hot pressing,using carbon materials with different pore size distributions as additives for commercial bi_(0.5)Sb_(1.5)Te_(3) thermoelectric material(BST,p-type).Thermoelectric properties of the composites were measured in a temperature range of 298-473 *** conductivity of the composites,especially lattice thermal conductivity,was effectively decreased due to the mesoporous properties of the incorporated carbon *** electrical conductivity of the composites slightly decreased due to the electron scattering at the interface between the carbon material and the commercial BST *** composite with 0.2 vol.%mesoporous carbon powder(36%mesoporosity)exhibited a figure of merit value approximately 10.7%higher than that of commercial BST without *** behavior resulted in 116%improved output power in the composite block-based single element compared with a bare BST thermoelectric *** enhanced figure of merit was attributed to the effective reduction of lattice thermal conductivity by acoustic phonons scattering at the interface between the BST matrix and the mesoporous carbon as well as at the pore surfaces within the mesoporous *** utilizing mesoporous carbon materials used in this study,the shortcomings and economic difficulties of the composite process with low dimensional carbon additives(carbon nanotubes,graphene,and nanodiamond)can be overcome for extensive practical *** carbon powder with a tailored porosity distribution revealed the validity of bulk-type carbon additives to enhance the figure of merit of commercial thermoelectric materials.

关键词： Thermoelectric material bi_(0.5)Sb_(1.5)Te_(3) Mesoporous carbon lattice thermal conductivity Figure of merit

Effect of atmospheric aerosol on surface ozone variation over the Pearl River Delta region

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Science China Earth Sciences 2011年第5期54卷 744-752页

作者： DENG XueJiao ZHOU XiuJi WU Dui TIE XueXi TAN HaoBo lI Fei bi XueYan DENG Tao JIANG DeHai Institute of Tropical and Marine Meteorology Key Open Laboratory for Tropical Monsoon China MeteorologicalAdministration Guangzhou 510080 China Chinese Academy of Meteorological Sciences CMA Beijing 100081 China National Center for Atmospheric Research Boulder CO USA

Our analysis of the surface aerosol and ultraviolet （UV） measurements in Pearl River Delta （PRD） region shows that the surface UV radiation is reduced by more than 50% due to high aerosol concentrations. This has important impacts on urban ecosystem and photochemistry, especially on ozone photochemical production over the region. The quantitative effect of aerosols on surface ozone is evaluated by analyzing surface observations （including ozone, ultraviolet radiation, aerosol radiative parameters） and by using radiative and chemical models. A case study shows that the aerosol concentrations and UV radiation are significantly correlated with ozone concentrations. The correlation coefficient between the aerosol optical depth （AOD） and the PM10 mass concentration is very high, with a maximum of 0.98, and the AOD and UV radiation/ozone is anti- correlated, with a correlation coefficient of-0.90. The analysis suggests that ozone productivity is significantly decreased due to the reduction of UV radiation. The noon-time ozone maximum is considerably depressed when AOD is 0.6, and is further decreased when AOD is up to 1.2 due to the reduction of ozone photochemical productivity. Because the occurring probability of aerosol optical depth for AOD550m≥0.6 and AOD340mm ≥1.0 is 47, and 55% respectively during the dry season （October, November, December, January）, this heavy aerosol condition explains the low ozone maximum that often occurs in the dry season over the Guangzhou region. The analysis also suggests that the value of single scattering albedo （SSA） is very sensitive to the aerosol radiative effect when the radiative and chemical models are applied, implying that the value of SSA needs to be carefully studied when the models are used in calculating ozone production.

关键词： atmospheric aerosol ozone photochemical process attenuation

Synthesis,Crystal Structure,Thermal Decomposition and Sensitive Properties of a New Complex [Cu(IMI)_4](pa)_2

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Chemical Research in Chinese Universities 2012年第4期28卷 585-589页

作者： WANG Shi-wei WU bi-dong YANG li ZHANG Tong-lai ZHOU Zun-ning ZHANG Jian-guo State Key laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing 100081P.R.China

A new coordination complex [Cu（IMI）4]（pa）2 had been synthesized with imidazole（IMI） as ligands and picrate（pa-） groups as outer anions,and characterized by Fourier transform infrared（FTIR） spectrum and elemental *** crystal structure was determined by single crystal X-ray diffraction（XRD） *** crystallographic data show that the crystal belongs to monoclinic,C2/c space group,a=2.542（5） nm,b=0.91773（18） nm,c=1.3778（3） nm,β=107.854（3）° and Z=***,the central copper（II） ion is coordinated by four N atoms from four imidazole *** the molecular units are linked into a zigzag pattern along a-axis by the hydrogen bonds,and extended to the distance *** decomposition mechanisms were determined based on differential scanning calorimetry（DSC） and thermogravimetry-differential thermogravimetry（TG-DTG） analysis,and kinetic parameters of the first exothermic process were studied using Kissinger＇s and Ozawa-Doyle＇s method,*** tests show that the title complex has low sensitivity to external stimulus,but it has a higher energy of combustion of 14.2 kJ/g due to which it may be used as the additives of energetic materials to improve the explosive performance.

关键词： Copper Imidazole Crystal structure Thermal decomposition Sensitivity

Effect of Tempered Martensite on Magnetomechanical Damping of Ferritic Matrix Dual Phase Alloys

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Journal of Materials Science & Technology 1993年第4期9卷 293-296页

作者： Junsheng lU Xiaodong lIU Wenjie ZHENG Baorong WU Hui bi Central Iron and Steel Research Institute,Beijing,100081,ChinaGuijin WANG Dept.of Materials Science and Engineering,University of Pennsylvania,Philadelphia,pa 19104,USA

The influence of the volume fraction of tempered martensite on magnetomechanical damping of the ferritic matrix in dual-phase alloys was *** experimental results showed that(1) dual-phase damping alloy is of good combination of strength and toughness: (2)good damping ca- pacity(Q^(-1)≥5.0×10^(-3))can be obtained in dual-phase alloys only when the volume fraction of tempered martensite was controlled *** effect of martensite on magnetomechanical damp- ing of the ferritic matrix was *** damping capacity of dual-phase alloys was related to the volume fraction V_m of tempered martensite by Q_^(-1)=Q_^(-1) (1-V_m/1+BV_m)at small vibration strain amplitudes ε_A≤5.0×10^(-6).

关键词： martensite damping dual-phase alloys

Restudy of the late Oligocene dormice from northern Junggar Basin

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古脊椎动物学报 2016年第1期54卷 36-50页

作者： WU Wen-Yu MENG Jin YE Jie NI Xi-Jun bi Shun-Dong Key laboratory of Vertebrate Evolution and Human Origins of Chinese Academy of Sciences Institute of Vertebrate Paleontology and Paleoanthropology Chinese Academy of Sciences Beijing 100044 China Division of paleontology American Museum of Natural -History New York NY 10024 USA Department of biology lndiana University of Pennsylvania Indiana PA 15705 USA

周氏似日本睡鼠Gliruloides zhoui是发现于新疆准噶尔盆地北缘晚渐新世铁尔斯哈巴合哺乳动物组合I带的一个化石新属种。新属似日本睡鼠Gliruloides的属征为:中等大小;颊齿咀嚼面凹;上、下颊齿通常具9条主要横脊,有时具次级附脊;上颊齿... 详细信息

周氏似日本睡鼠Gliruloides zhoui是发现于新疆准噶尔盆地北缘晚渐新世铁尔斯哈巴合哺乳动物组合I带的一个化石新属种。新属似日本睡鼠Gliruloides的属征为:中等大小;颊齿咀嚼面凹;上、下颊齿通常具9条主要横脊,有时具次级附脊;上颊齿的前边附脊和后边附脊以及下颊齿的下前边附脊和下后边附脊都很发育,几乎占据了其所在齿谷的整个长度。上颊齿的横脊唇端趋于游离。M1和M2具V形或窄U形三角座,内脊不完整或近于完整,前中央脊不与内脊相连。下颊齿的下内脊通常不连续;下臼齿的下前边脊在唇端稍向后弯,但不与原尖相连。p4,m1-m3,P4,M1-M3的齿根数分别为2,2,3,3。新属与Glirulus在形态上相似,但Glirulus的上颊齿的三角座均为宽U型,具有完整的内脊,前中央脊通常与内脊相交,横脊唇端通常不游离。新属与Vasseuromys属的最主要形态差异在于上颊齿具有很发育的前边附脊和后边附脊,而后者上颊齿的前边附脊和后边附脊通常缺失或很不发育。归入该属的种还有土耳其早中新世的Vasseuromys duplex和Vasseuromys ***。土耳其Thrace早渐新世的Glis guerbuezi很可能是Gliruloides和Glirulus的共同祖先类型。Gliruloides可能生活于温湿的生态环境。

关键词：准噶尔盆地北缘晚渐新世铁尔斯哈巴合哺乳动物组合I带睡鼠

The effects of FDI inflows on income inequality:Evidence from OECD countries

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金融管理研究 2021年第1期14卷 1-30页

作者： lufei Teng Qianwen bi Department of Economics and Finance Muhlenberg College2400 Chew StreetAllentownPA 18104 Department of Finance and Economics Woodbury School of BusinessUtah Valley UniversityMS 280800 West University ParkwayOremUtah 84058Rachel

Income inequality is a concerned topic that attracts academia studies for many *** the long list of factors offered by scholars that contribute to income inequality,the impact of globalization has been extensively *** study uses a three-step analysis to examine the influence of Foreign Direct Investment(FDI)inflows on income distribution for Organization for Economic Cooperation(OECD)countries through panel data analysis *** flows into OECD countries are generally driven by high skilled *** inflows to OECD countries increase GINI coefficients and widen income gaps due to their skill-intensive nature.A high level of education should be encouraged as indicated by its negative relationship with the GINI index.

关键词： Income inequality Foreign Direct Investment(FDI) Organization for Economic Cooperation(OECD)

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鼻咽癌并发肛周脓肿1例

中医眼耳鼻喉杂志 2024年第2期14卷 112-114页

作者：毕苇李祥周建平周子宁邓智宇付皓成都中医药大学附属医院四川成都610072

鼻咽癌(NPC)是鼻咽部发生的恶性肿瘤,其放化疗期间并发肛周脓肿(pa)的病例较少见。从中医整体观念分析,考虑本患者pa发病与NPC放化疗期间正气虚损、鼻咽部经络循行密切相关。本患者正气虚损后易引起热、痰、瘀、毒积聚,临床表现多为肺... 详细信息

鼻咽癌(NPC)是鼻咽部发生的恶性肿瘤,其放化疗期间并发肛周脓肿(pa)的病例较少见。从中医整体观念分析,考虑本患者pa发病与NPC放化疗期间正气虚损、鼻咽部经络循行密切相关。本患者正气虚损后易引起热、痰、瘀、毒积聚,临床表现多为肺、脾、肾、肝脏器功能失调,辨证后以清热解毒、化痰散结、行气通窍等中药治之,发现能有效提升患者正气,减轻其不适症状。

关键词：鼻咽癌肛周脓肿病因中医药

Characteristics of an Explosive Cyclone over Northeast China Revealed by Satellite Water Vapor Imagery

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Journal of Tropical Meteorology 2022年第3期28卷 261-272页

作者： YANG Xiao-liang YAO Xiu-ping YANG Yue YANG Min CHEN bi-ying Hebei Meteorological Observatory Shijiazhuang 050021 China Hebei laboratory for Meteorological and Ecoenvironment Shijiazhuang 050021 China State Key laboratory of Severe Weather Chinese Academy of Meteorological SciencesBeijing 100081 China China Meteorological Administration Training Centre Beijing 100081 China Shijiazhuang Meteorological Bureau Shijiazhuang 050081 China Hebei Provincial Meteorological Administrative&Technical Service Center Shijiazhuang 050021 China

In this paper,an explosive cyclone(EC)that occurred over Northeast China in the spring of 2016 is studied by using 6.7μm FY satellite water vapor(WV)imagery and NCEP(1°×1°)reanalysis ***,the evolutions of the upper-level jet stream(UlJ),the vertical motions,and the potential vorticity(PV)are analyzed in *** show that different shapes of the WV image dark zones could reflect different stages of the *** the pre-explosion stage,a small dark zone and an S-shaped baroclinic leaf cloud can be found on the WV *** the dark zone expands and the leaf cloud grows into a comma-shaped cloud at the explosively developing *** the post-explosion stage,the dark zone brightens,and the spiral cloud *** whole process can be well described by the WV *** dynamic dry band associated with the sinking motion and the UlJ can develop into the dry intrusion later,which is an important signal in forecasting the EC and should be paid attention to when analyzing the WV ***,the mechanism is also analyzed in detail in this *** usually occurs in the left-exit region of the 200-h pa jet and the region ahead of the 500-h pa trough where there is significant positive vorticity advection(PVA).When the EC moves onto the sea surface,the decreased friction would favour the development of the *** upper-level PVA,the strong convergence at low level,and the divergence at high levels can maintain the strong ***,the high PV zone from the upper levels extends downward,approaching the ***,they keep the cyclone deepening continuously.

关键词： satellite water vapor imagery explosive cyclone dry intrusion physical quantity configuration

Exploring the sources of p-mode frequency shifts in the CoRoT target HD 49933

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Research in Astronomy and Astrophysics 2014年第6期14卷 683-692页

作者： Zhi-E liu Shao-lan bi Wu-Ming Yang Tan-Da li Kang liu Zhi-Jia Tian Zhi-Shuai Ge Jie Yu Department of Astronomy Beijing Normal University Key laboratory of Solar Activity National Astronomical Observatories Chinese Academy of Science

Oscillations of the solar-like star HD 49933 have been thoroughly observed by CoRot. Two dozen frequency shifts, which are closely related to the change in magnetic activity, have been measured. To explore the effects of magnetic activity on frequency shifts, we calculate frequency shifts for the radial and l=1 p-modes of HD 49933 with the general variational method, which evaluates the shifts using a spa- tial integral of the product of a kernel and some sources. The theoretical frequency shifts reproduce the observation well. The magnitudes and positions of the sources are determined according to a χ2 criterion. We predict the source that contributes to both the l = 0 and l= 1 modes is located 0.48 - 0.62 Mm below the surface of the star. In addition, based on the assumption that A0 is proportional to the change in the MglI activity index △iMgⅡ, we obtain that the change in MgⅡ index between the minimum and maximum of the cycle during the period of HD 49933 is about 0.665. The magnitude of the frequency shifts compared to the Sun already demonstrates that HD 49933 is much more active than the Sun, which is further confirmed in this pa- per. Furthermore, our calculation of the frequency shifts for l = 1 modes indicates the variation of turbulent velocity in the stellar convective zone may be an important source for the l = 1 shifts.

关键词： stars: individual (HD 49933) -- stars: evolution -- stars: oscillation --stars: modeling