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1Characteristics of one-year observation of VOCs,NOx, and O_3 at an urban site in Wuhan, China显示文摘A continuous online observation of ozone and its precursors(NOx, VOCs) was carried out in central urban Wuhan from September 2016 to August 2017. The concentration levels of ozone,NOx, VOCs and their variations in urban Wuhan were analyzed, as well as effects of VOCs on ozone photochemical generation and the main controlling factors for ozone production. During the observation period, the average concentrations of ozone and NOx in Wuhan was 22.63 and30.14 ppbv, respectively, and the average concentration of VOCs was 32.61 ppbv(42.3% alkanes,13.0% alkenes, 10.0% aromatics, 7.3% acetylene, 9.9% OVOCs, and 10.5% halohydrocarbons).Ozone concentration was higher in spring and summer as compared with autumn and winter,wheras VOCs and NOx concentratios were lower in spring and summer but higher in autumn and winter. Aromatics and alkenes, two of VOCs species, showed the highest contributions to ozone formation potential in Wuhan(35.7% alkenes, 35.4 aromatics, 17.5% alkanes, 8.6% OVOCs,1.6% halogenated hydrocarbons, and 1.4% acetylene). Among all VOCs species, those with the highest contribution were ethylene, m-xylene, toluene, propylene and o-xylene. The contribution of these five compounds to the total ozone formation potential concentration was 43.90%.Ozone-controlling factors in Wuhan changed within one day; during the early morning hours(6:00–9:00), VOCs/NOx was low, and ozone generation followed a VOCs-limited regime.However, during the peak time of ozone concentration(12:00–16:00), the ratio of VOCs/NOx was relatively high, suggesting that ozone generation followed a NOx-limited regime.Yichang Yang Xingang Liu Jun Zheng Qinwen Tan Miao Feng Yu Qu Junling An Nianliang Cheng 2019Journal of Environmental Sciences2019,31,5:26
2Prognostic value of clinical and pathological factors for surgically treated localized clear cell renal cell carcinoma显示文摘Teng Jingfei Gao Yi Chen Ming Wang Kai Cui Xingang Liu Yushan Xu Danfeng 2014Chinese Medical Journal2014,,9:23
3Role of secondary aerosols in haze formation in summer in the Megacity Beijing显示文摘A field experiment from 18 August to 8 September 2006 in Beijing, China, was carried out. A hazy day was defined as visibility < 10 km and RH(relative humidity) < 90%. Four haze episodes, which accounted for ~ 60% of the time during the whole campaign, were characterized by increases of SNA(sulfate, nitrate, and ammonium) and SOA(secondary organic aerosol) concentrations. The average values with standard deviation of SO2-+4, NO-3, NH4 and SOA were 49.8(± 31.6), 31.4(±22.3), 25.8(±16.6) and 8.9(±4.1) μg/m3, respectively, during the haze episodes, which were 4.3, 3.4, 4.1, and 1.7 times those in the non-haze days. The SO2-4,NO-3, NH+4, and SOA accounted for 15.8%, 8.8%, 7.3%, and 6.0% of the total mass concentration of PM10 during the non-haze days. The respective contributions of SNA species to PM10 rose to about27.2%, 15.9%, and 13.9% during the haze days, while the contributions of SOA maintained the same level with a slight decrease to about 4.9%. The observed mass concentrations of SNA and SOA increased with the increase of PM10 mass concentration, however, the rate of increase of SNA was much faster than that of the SOA. The SOR(sulfur oxidation ratio) and NOR(nitrogen oxidation ratio) increased from non-haze days to hazy days, and increased with the increase of RH. High concentrations of aerosols and water vapor favored the conversion of SO2 to SO2-4and NO2 to NO-3, which accelerated the accumulation of the aerosols and resulted in the formation of haze in Beijing.Tingting Han Xingang Liu Yuanhang Zhang Yu Qu Limin Zeng Min Hu Tong Zhu 2015Journal of Environmental Sciences2015,27,5:22
4Chemical characterization of size-resolved aerosols in four seasons and hazy days in the megacity Beijing of China显示文摘Size-resolved aerosol samples were collected by MOUDI in four seasons in 2007 in Beijing. The PM10 and PM1.8mass concentrations were 166.0 ± 120.5 and 91.6 ± 69.7 μg/m^3, respectively,throughout the measurement, with seasonal variation: nearly two times higher in autumn than in summer and spring. Serious fine particle pollution occurred in winter with the PM1.8/PM10 ratio of 0.63, which was higher than other seasons. The size distribution of PM showed obvious seasonal and diurnal variation, with a smaller fine mode peak in spring and in the daytime. OM(organic matter = 1.6 × OC(organic carbon)) and SIA(secondary inorganic aerosol) were major components of fine particles, while OM, SIA and Ca_2+were major components in coarse particles. Moreover, secondary components, mainly SOA(secondary organic aerosol) and SIA,accounted for 46%–96% of each size bin in fine particles, which meant that secondary pollution existed all year. Sulfates and nitrates, primarily in the form of(NH_4)_2SO_4, NH_4NO_3, Ca SO_4, Na_2SO_4 and K_2SO_4, calculated by the model ISORROPIA II, were major components of the solid phase in fine particles. The PM concentration and size distribution were similar in the four seasons on non-haze days, while large differences occurred on haze days, which indicated seasonal variation of PM concentration and size distribution were dominated by haze days. The SIA concentrations and fractions of nearly all size bins were higher on haze days than on non-haze days, which was attributed to heterogeneous aqueous reactions on haze days in the four seasons.Kang Sun Xingang Liu Jianwei Gu Yunpeng Li Yu Qu Junling An Jingli Wang Yuanhang Zhang Min Hu Fang Zhang 2015Journal of Environmental Sciences2015,27,6:19
5Chemical and optical properties of aerosols and their interrelationship in winter in the megacity Shanghai of China显示文摘A field campaign on air quality was carried out in Shanghai in winter of 2012. The concentrations of NO, NO2, NOx, SO2, CO, and PM2.5increased during haze formation. The average masses of SO42-, NO3-and NH4+were 10.3, 11.7 and 6.7 μg/m3 during the haze episodes, which exceeded the average(9.2, 7.9, and 3.4 μg/m3) of these components in the non-haze days. The mean values for the aerosol scattering coefficient(b sp), aerosol absorption coefficient(b ap) and single scattering albedo(SSA) were 288.7, 27.7 and0.91 Mm-1, respectively. A bi-peak distribution was observed for the mass concentrations of CO, NO, NO2, and NOx. More sulfate was produced during daytime than that in the evening due to photochemical reactions. The mass concentration of NH4+achieved a small peak at noontime. NO3-showed lower concentrations in the afternoon and higher concentrations in the early morning. There were obvious bi-peak diurnal patterns for b sp and b ap as well as SSA. b sp and b ap showed a positive correlation with PM2.5mass concentration.(NH4)2SO4, NH4NO3, organic mass, elemental carbon and coarse mass accounted for 21.7%, 19.3%, 31.0%, 9.3% and 12.3% of the total extinction coefficient during non-haze days, and 25.6%, 24.3%, 30.1%, 8.1% and 8.2% during hazy days. Organic matter was the largest contributor to light extinction. The contribution proportions of ammonium sulfate and ammonium nitrate to light extinction were significantly higher during the hazy time than during the non-haze days.Tingting Han Liping Qiao Min Zhou Yu Qu Jianfei Du Xingang Liu Shengrong Lou Changhong Chen Hongli Wang Fang Zhang Qing Yu Qiong Wu 2015Journal of Environmental Sciences2015,27,1:14
6Ductile deformation within Upper Himalaya Crystalline Sequence and geological implications,in Nyalam area,Southern Tibet显示文摘The South Tibet Detachment System(STDS) is a flat normal fault that separates the Upper Himalaya Crystalline Sequence(UHCS) below from the Tethyan Sedimentary Sequence(TSS) above.Timing of deformations related to the STDS is critical to understand the mechanism and evolution of the Himalaya collision zone.The Nyalam detachment(ND)(~86°E) locates in the middle portion of STDS(81°-89°E).Dating of deformed leucocratic dykes that are most probably syntectonic at different depth beneath the ND,allow us to constrain the timing of deformation.(1) Dyke T11N37 located ~3500 m structurally below the ND emplaced at 27.4± 0.2 Ma;(2) Dyke T11N32 located ~1400 m structurally below the ND emplaced at 22.0±0.3 Ma;(3) T11N25 located within the top to the north STD shear zone,~150 m structurally below the ND,emplaced at 17.1±0.2 Ma.Combining ND footwall cooling history and T11N25 deformation temperature,we indicate a probable onset of top to the north deformation at ~16 Ma at this location.These results show an upward younging of the probable timing of onset of the deformation at different structural distance below the ND.We then propose a new model for deformation migration below the ND with deformation starting by pure shear deformation at depth prior to ~27.5 Ma that migrates upward at a rate of ~ 0.3 mm/a until ~18 Ma when deformation switches to top to the north shearing in the South Tibet Detachment shear zone(STDsz).As deformation on the ND stops at 14-13 Ma this would imply that significant top to the North motion would be limited to less than 5 Ma and would jeopardize the importance of lower channel flow.LIU XiaoBing LIU XiaoHan LELOUP P.H. MAHEO G. PAQUETTE J.L. ZHANG XinGang ZHOU XueJun 2012Chinese Science Bulletin2012,57,26:14
7Effects of NO_x and VOCs from Five Emission Sources on Summer Surface O_3 over the Beijing–Tianjin–Hebei Region显示文摘The impacts of emissions from industry, power plant, transportation, residential, and biogenic sources on daily maximum surface ozone(O3DM) over the Beijing–Tianjin–Hebei(BTH) region in North China in the summer of 2007 were examined in a modeling study. The modeling system consisted of the Weather Research and Forecasting(WRF) model and the photochemical dispersion model, CAMx. The factor separation technique(FST) was used to quantify the effect of individual emission source types and the synergistic interactions among two or more types. Additionally, the effectiveness of emission reduction scenarios was explored. The industry, power plant, and transportation emission source types were found to be the most important in terms of their individual effects on O3DM. The key contributor to high surface O3was power plant emissions, with a peak individual effect of 40 ppbv in the southwestern BTH area. The individual effect from the biogenic emission category was quite low. The synergistic effects from the combinations of each pair of anthropogenic emission types suppressed O3formation, while the synergistic effects for combinations of three were favorable for O3formation when the industrial and power plant emission source types coexisted. The quadruple synergistic effects were positive only with the combination of power plant, transportation, residential, and biogenic sources, while the quintuple synergistic effect showed only minor impacts on O3DMconcentrations. A 30% reduction in industrial and transportation sources produced the most effective impacts on O3concentrations, with a maximum decrease of 20 ppbv. These results suggested that the synergistic impacts among emission source types should be considered when formulating emission control strategies for O3reduction.QU Yu AN Junling LI Jian CHEN Yong LI Ying LIU Xingang HU Min 2014Advances in Atmospheric Sciences2014,31,4:13
8Characteristics and formation mechanism of regional haze episodes in the Pearl River Delta of China显示文摘To investigate the characteristics and the specific mechanism of continuous haze,comprehensive measurements were conducted from 15 October to 19 November in the Atmospheric Environment Monitoring Super-Station in Heshan of Guangdong province.Five haze episodes occurred in October and November 2014 in the Pearl River Delta(PRD)region. The meteorological parameters, gas data, chemical compositions, and optical parameters of the aerosols were obtained. Among these events, the second haze episode,with the highest concentration of PM2.5 of 187.51 μg/m^3, was the most severe. NO^3-was always higher than SO_4^(2-), which indicated that motor vehicles played an important role in the haze, even though the oxidation rate from SO_2 to SO_4^(2-)was faster than that of NOXto NO_3^-. The difference between the hourly averages of Na+and K+during the haze episode and clean days was small, implying that straw combustion and sea salt had no significant effect on the occurrence of haze, and the backward trajectories of the air masses also conformed with this result. The air pollutants were difficult to disperse because of the significant decrease in the planetary boundary layer(PBL) height. Relative humidity played a crucial role in the formation of haze by leading to hygroscopic growth of the diameter of aerosols.Wenguang Li Xingang Liu Yuanhang Zhang Kang Sun Yusheng Wu Rui Xue Limin Zeng Yu Qu Junling An 2018Journal of Environmental Sciences2018,30,1:11
9Chemical characteristics of size-resolved aerosols in winter in Beijing显示文摘Size-resolved aerosols were continuously collected by a Nano Sampler for 13 days at an urban site in Beijing during winter 2012 to measure the chemical composition of ambient aerosol particles. Data collected by the Nano Sampler and an ACSM(Aerodyne Aerosol Chemical Speciation Monitor) were compared. Between the data sets,similar trends and strong correlations were observed,demonstrating the validity of the Nano Sampler. PM10 and PM2.5concentrations during the measurement were 150.5 ± 96.0 μg/m3(mean ± standard variation)and 106.9 ± 71.6 μg/m3,respectively. The PM2.5/PM10 ratio was 0.70 ± 0.10,indicating that PM2.5dominated PM10. The aerosol size distributions showed that three size bins of 0.5–1,1–2.5 and 2.5–10 μm contributed 21.8%,23.3% and 26.0% to the total mass concentration(TMC),respectively. OM(organic matter) and SIA(secondary ionic aerosol,mainly SO42-,NO3-and NH4+) were major components of PM2.5. Secondary compounds(SIA and secondary organic carbon) accounted for half of TMC(about 49.8%) in PM2.5,and suggested that secondary aerosols significantly contributed to the serious particulate matter pollution observed in winter. Coal burning,biomass combustion,vehicle emissions and SIA were found to be the main sources of PM2.5. Mass concentrations of water-soluble ions and undetected materials,as well as their fractions in TMC,strikingly increased with deteriorating particle pollution conditions,while OM and EC(elemental carbon) exhibited different variations,with mass concentrations slightly increasing but fractions in TMC decreasing.Kang Sun Yu Qu Qiong Wu Tingting Han Jianwei Gu Jingjing Zhao Yele Sun Qi Jiang Ziqi Gao Min Hu Yuanhang Zhang Keding Lu Stephan Nordmann Yafang Cheng Li Hou Hui Ge Masami Furuuchi Mitsuhiko Hata Xingang Liu 2014Journal of Environmental Sciences2014,26,8:9
10Vertical distribution of aerosol optical properties based on aircraft measurements over the Loess Plateau in China显示文摘Vertical distributions of aerosol optical properties based on aircraft measurements over the Loess Plateau were measured for the first time during a summertime aircraft campaign, 2013 in Shanxi, China. Data from four flights were analyzed. The vertical distributions of aerosol optical properties including aerosol scattering coefficients(σsc), absorption coefficients(σab),Angstr?m exponent(α), single scattering albedo(ω), backscattering ratio(βsc), aerosol mass scattering proficiency(Q sc) and aerosol surface scattering proficiency(Q sc′) were obtained. The mean statistical values of σsc were 77.45 Mm-1(at 450 nm), 50.72 Mm-1(at 550 nm), and32.02 Mm-1(at 700 nm). The mean value of σab was 7.62 Mm-1(at 550 nm). The mean values ofα, βsc and ω were 1.93, 0.15, and 0.91, respectively. Aerosol concentration decreased with altitude. Most effective diameters(ED) of aerosols were less than 0.8 μm. The vertical profiles of σsc,, α, βsc, Q sc and Q sc′ showed that the aerosol scattering properties at lower levels contributed the most to the total aerosol radiative forcing. Both α and βsc had relatively large values, suggesting that most aerosols in the observational region were small particles. The mean values of σsc, α, βsc, Q sc, Q sc′, σab and ω at different height ranges showed that most of the parameters decreased with altitude. The forty-eight hour backward trajectories of air masses during the observation days indicated that the majority of aerosols in the lower level contributed the most to the total aerosol loading, and most of these particles originated from local or regional pollution emissions.Junxia Li Xingang Liu Liang Yuan Yan Yin Zhanqing Li Peiren Li Gang Ren Lijun Jin Runjun Li Zipeng Dong Yiyu Li Junmei Yang 2015Journal of Environmental Sciences2015,27,8:6
11Evaluation of asthma control: a questionnaire-based survey in China显示文摘Su Nan Lin Jiangtao Chen Ping Li Jing Wu Changgui Yin Kaisheng Liu Chuntao Chen Yiqiang Zhou Xin Yuan Yadong Huang Xingang 2014Chinese Medical Journal2014,,11:5
12Ablation characteristics of mosaic structure ZrC-SiC coatings on low-density, porous C/C composites显示文摘Mosaic structure ZrC-SiC coatings were fabricated on low-density, porous C/C composites via thermal evaporation and an in-situ method. ZrC was packed in a typical lamellar mode, and the mosaic structure was formed by the deposition of Zr and Si atoms on the shallow surface of the porous C/C composites.Ablation analysis showed that the defects in the coatings originate from the boundary between the ZrC and holes created by the consumption of SiC at 2500℃. After ablation for 200 s at 3000℃, a dense ZrO2 layer formed on the coating surface, and the defects were sealed owing to the continuous supply of ablative components. The mass and line ablation rates of the Zr C-SiC coatings were-0.46 ± 0.15 mg cm^-2·s^-1 and-1.00± 0.04 μm s^-1, respectively.Yonglong Xu Wei Sun Xiang Xiong Fuqun Liu Xingang Luan 2019Journal of Materials Science & Technology2019,35,12:4
13In situ monitoring of atmospheric nitrous acid based on multi-pumping flow system and liquid waveguide capillary cell显示文摘In the last four decades, various techniques including spectroscopic, wet chemical and mass spectrometric methods, have been developed and applied for the detection of ambient nitrous acid(HONO). We developed a HONO detection system based on long path photometry which consists of three independent modules i.e., sampling module, fluid propulsion module and detection module. In the propulsion module, solenoid pumps are applied. With solenoid pumps the pulsed flow can be computer controlled both in terms of pump stroke volume and pulse frequency, which enables the attainment of a very stable flow rate. In the detection module, a customized Liquid Waveguide Capillary Cell(LWCC) is used. The customized LWCC pre-sets the optical fiber in-coupling with the liquid wave guide, providing the option of fast startup and easy maintenance of the absorption photometry. In summer 2014, our system was deployed in a comprehensive campaign at a rural site in the North China Plain. More than one month of high quality HONO data spanning from the limit of detection to 5 ppb were collected. Intercomparison of our system with another established system from Forschungszentrum Juelich is presented and discussed. In conclusion, our instrument achieved a detection limit of 10 ppt V within2 min and a measurement uncertainty of 7%, which is well suited for investigation of the HONO budget from urban to rural conditions in China.Yuhan Liu Keding Lu Huabin Dong Xin Li Peng Cheng Qi Zou Yusheng Wu Xingang Liu Yuanhang Zhang 2016Journal of Environmental Sciences2016,28,5:4
14Critical function of DNA methyltransferase 1 in tomato development and regulation of the DNA methylome and transcriptome显示文摘DNA methylation confers epigenetic regulation on gene expression and thereby on various biological processes.Tomato has emerged as an excellent system to study the function of DNA methylation in plant development.To date,regulation and function of DNA methylation maintenance remains unclear in tomato plants.Here,we report the critical function of tomato(Solanum lycopersicum)Methyltransferase 1(Sl MET1)in plant development and DNA methylome and transcriptome regulation.Using CRISPR-Cas9 gene editing,we generated slmet1 mutants and observed severe developmental defects with a frame-shift mutation,including small and curly leaves,defective inflorescence,and parthenocarpy.In leaf tissues,mutations in Sl MET1 caused CG hypomethylation and CHH hypermethylationon a whole-genome scale,leading to a disturbed transcriptome including ectopic expression of many RIN target genes such as ACC2 in leaf tissues,which are normally expressed in fruits.Neither the CG hypomethylation nor CHH hypermethylation in the slmet1 mutants is related to tissue culture.Meanwhile,tissue culture induces non-CG hypomethylation,which occurs more frequently at gene regions than at TE regions.Our results depict Sl MET1-and tissue culture-dependent tomato DNA methylomes,and that Sl MET1 is required for maintaining a normal transcriptome and normal development of tomato.Yu Yang Kai Tang Tatsiana U Datsenka Wenshan Liu Suhui Lv Zhaobo Lang Xingang Wang Jinghui Gao Wei Wang Wenfeng Nie Zhaoqing Chu Heng Zhang Avtar K HANDa Jian-Kang Zhu Huiming Zhang 2019Journal of Integrative Plant Biology2019,61,12:3
15Effects of Tidal Currents on Nonlinear Internal Solitary Waves in the South China Sea显示文摘The propagation and fission process of internal solitary waves (ISWs) with amplitudes of about 170 m are simulated in the northeast of the South China Sea (NSCS) by using the generalized Korteweg-de Vries (KdV) equation under continuous stratification. More attention is paid to the effects of the ebb and flood background currents on the fission process of ISWs. This kind of background current is provided by the composed results simulated in terms of monthly mean baroclinic circulation and barotropic tidal current. It is found that the obtained relation of the number of fission solitons to the water depth and stratification is roughly in accordance with the fission law derived by Djordjevic and Redekopp in 1978; however, there exists obvious difference between the effects of the ebb and flood background currents on the wave-lengths of fission solitons (defined as the distance between two neighboring peaks of ISWs). The difference in nonlinearity coefficient α between the ebb and flood background currents is a main cause for the different wave-lengths of fission solitons.FAN Zhisong SHI Xingang Antony K. Liu LIU Hailong LI Peiliang 2013Journal of Ocean University of China2013,12,1:3
16Effect of potential HONO sources on peroxyacetyl nitrate(PAN)formation in eastern China in winter显示文摘As an important secondary photochemical pollutant,peroxyacetyl nitrate(PAN)has been studied over decades,yet its simulations usually underestimate the corresponding observations,especially in polluted areas.Recent observations in north China found unusually high concentrations of PAN during wintertime heavy haze events,but the current model still cannot reproduce the observations,and researchers speculated that nitrous acid(HONO)played a key role in PAN formation.For the first time we systematically assessed the impact of potential HONO sources on PAN formation mechanisms in eastern China using the Weather Research and Forecasting/Chemistry(WRF-Chem)model in February of 2017.The results showed that the potential HONO sources significantly improved the PAN simulations,remarkably accelerated the RO x(sum of hydroxyl,hydroperoxyl,and organic peroxy radicals)cycles,and resulted in 80%–150%enhancements of PAN near the ground in the coastal areas of eastern China and 10%–50%enhancements in the areas around 35–40°N within 3 km during a heavy haze period.The direct precursors of PAN were aldehyde and methylglyoxal,and the primary precursors of PAN were alkenes with C>3,xylenes,propene and toluene.The above results suggest that the potential HONO sources should be considered in regional and global chemical transport models when conducting PAN studies.Jingwei Zhang Yitian Guo Yu Qu Yong Chen Ruipeng Yu Chaoyang Xue Rui Yang Qiang Zhang Xingang Liu Yujing Mu Jing Wang Can Ye Haihan Zhao Qiangqiang Sun Ziwen Wang Junling An 2020Journal of Environmental Sciences2020,32,8:3
17Aerosol optical properties under different pollution levels in the Pearl River Delta(PRD) region of China显示文摘To clarify the aerosol hygroscopic growth and optical properties of the Pearl River Delta(PRD)region,integrated observations were conducted in Heshan City of Guangdong Province from October 19 to November 17,2014.The concentrations and chemical compositions of PM2.5,aerosol optical properties and meteorological parameters were measured.The mean value of PM2.5 increased from less than 35(excellent)to 35-75μg/m^3(good)and then to greater than 75μg/m^3(pollution),corresponding to mean PM2.5 values of 24.9,51.2,and 93.3μg/m^3,respectively.The aerosol scattering hygroscopic growth factor(f(RH=80%))values were 2.0,2.12,and 2.18 for the excellent,good,and pollution levels,respectively.The atmospheric extinction coefficient(σext)and the absorption coefficient of aerosols(σap)increased,and the single scattering albedo(SSA)decreased from the excellent to the pollution levels.For different air mass sources,under excellent and good levels,the land air mass from northern Heshan had lower f(RH)andσsp values.In addition,the mixed aerosol from the sea and coastal cities had lower f(RH)and showed that the local sources of coastal cities have higher scattering characteristics in pollution periods.Liuwei Kong Min Hu Qinwen Tan Miao Feng Yu Qu Junling An Yuanhang Zhang Xingang Liu Nianliang Cheng 2020Journal of Environmental Sciences2020,32,1:3
18sEMG based quantitative assessment of acupuncture on Bell's palsy:an experimental study显示文摘Acupuncture is a traditional Chinese therapeutic method, recognized by western medicine as an important complementary therapy. However, the efficacy assessment of this traditional intervention has been mainly empirical rather than scientific. In this paper, we propose a surface electromyography(s EMG) based approach for quantitative assessment of acupuncture on Bell's palsy. The assessment is made by comparing the muscle activities of healthy with diseased ones. A feature-vector of four individual s EMG features is introduced for more comprehensive representation of muscle activity. A clustering technique is then proposed to calculate quantitative differences between the muscle activities of the healthy and diseased sides. A regressive model is also proposed to predict the recovery trend of a patient based on the quantitative assessments during his/her clinical acupuncture history. As reported in the paper, a total of 20 selected Bell's palsy patients have participated in the extensive experiments that were conducted to verify the performance of the proposed method.HAN JianDa XIONG AnBin ZHAO XinGang DING QiChuan CHEN YiGuo LIU GuangJun 2015Science China(Information Sciences)2015,58,8:3
19Branching random walks with random environments in time显示文摘我们考虑分叉的随机的散步在上与随机的环境及时(表示了由) 。让 Z < 潜水艇 class= “ a-plus-plus ” > n 产生 n 的粒子的数的措施,和 let\(\tilde Z_n (t)\) 是它的 Laplace 变换。我们显示出免费精力 n 的集中<啜class=“ a-plus-plus ”> 1 log\( \tilde Z_n (t)\),大偏差原则,并且为措施的顺序的中央限制定理{ Z <潜水艇class=“ a-plus-plus ”>为martingale\的限制的时刻的存在的 n },和一个必要、足够的条件( \tilde Z_n (t) /\mathbb { E }[ \tilde Z_n (t)| \xi ]\)。Chuamao HUANG Xingang LIANG Quansheng LIU 2014Frontiers of Mathematics in China2014,9,4:3
20Preparation and Arc Erosion Resistance of C_f/Cu Composite by Vacuum Melting Infiltration显示文摘Cf/Cu composite was prepared by vacuum melting infiltration. Tiand Cr were doped to the Cu alloy to improve the wettability between Cu and carbon. The microstructure was investigated by XRD, SEM and EDS. The arc erosion rate of Cf/Cu composite was investigated in vacuum. The results showed that the Tiand Cr could improve the wettability between Cu and C/C preform and the infiltration ability of Cu into C/C preform greatly. A TiC interface formed between the fibers and matrix. The good bonding between the fiber and matrix guaranteed that part of the Cu matrix can still be bonded on the fibers even when the material was exposed to the plasma. Consequently, the carbon fibers were protected from the erosion. In comparison, Cu was completely consumed by the arc erosion. Hence, the graphite was eroded and presented a caulifl ower-like morphology. Therefore, the prepared Cf/Cu had better ability to resist the arc erosion, compared with common Cu-C material.张华煜 LIU Yiwen ZHAO Xianling LUAN Xingang 2014Journal of Wuhan University of Technology(Materials Science)2014,29,5:3
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