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| 1 | 上海地区臭氧周末效应研究显示文摘分析了2006年上海5个臭氧监测站(徐家汇、崇明、宝山、浦东和金山)周末与工作日臭氧浓度的变化规律,发现上海徐家汇与国外许多城市中心一样,存在周末臭氧浓度比工作日高,而臭氧前体物NO,NO2,CO和VOCs的浓度却是周末要比工作日低的“臭氧周末效应”.一方面,上海徐汇区NO2/NO在周末比工作日要高25.61%,NO排放的减少是造成上海臭氧周末效应可能的化学原因;另一方面,上海徐家汇由于周末NOx(NO+NO2)比工作日在清晨(05:00-09:00)平均减少近12.13%,使清晨NO抑制臭氧生成的持续时间比工作日少近半个小时,周末臭氧积累持续时间更长,臭氧平均生成速率更大.臭氧的产生率是关于环境中VOCs与NOx混合比率的函数.上海徐家汇VOCs与NOx比率周末为4.55,工作日为4.37,位于VOC敏感区.由于周末NOx和VOCs减少,VOCs/NOx比率增加,使臭氧从73mL/L增加到80nL/L,这与上海徐家汇的“周末效应”基本一致.利用MICAPS云量资料做进一步分析.周末、工作日臭氧值都随云量增加而降低,并且明显发现徐家汇臭氧“周末效应”随云量增加而逐渐减弱.云量的增加最终结果使臭氧“周末效应”几乎消失,说明徐家汇臭氧“周末效应”是由于臭氧光化学生成引起的. | 唐文苑 赵春生 耿福海 彭丽 周广强 高伟 许建明 Xuexi Tie | 2009 | 中国科学(D辑)2009，39，1： | 103 |
| 2 | Black carbon aerosols and their radiative properties in the Pearl River Delta region显示文摘The climatic and environmental effects of atmospheric aerosols are a hot topic in global science community, and radiative properties of the aerosols are one of the important parameters in assessing climatic change. Here we studied the black carbon concentration and absorption coefficient measured with aethalometers, scattering coefficient measured with nephelometers, and single scattering albedo derived at an atmospheric composition watch station in Guangzhou from 2004 to 2007. Our main results are as follows. The data of black carbon concentration and absorption coefficients measured with instruments cannot be directly used until they are measured in parallel with internationally accepted instruments for comparison, calibration, and reduction. After evaluation of the data, the result shows that the monthly mean of BC concentration varies 3.1―14.8 μg·m-3 and the concentration decreases by about 1 μg·m-3 in average over the four years; It is higher in the dry season with a multi-year mean of 8.9 μg/m3 and lower in the rainy season with a multi-year mean of 8.0 μg·m-3; The extreme maximum of monthly mean concentration occurred in December 2004 and extreme minimum in July 2007, and a 4-year mean is 8.4 μg·m-3. It is also shown that monthly mean scattering coefficient derived varies 129 -565 Mm-1, monthly mean absorption coefficient 32-139 Mm-1, and monthly mean single scattering albedo 0.71-0.91, with annual mean values of 0.80, 0.82, 0.79 and 0.84 for 2004, 2005, 2006 and 2007, respectively. Three instruments were used to take simultaneous measurements of BC in PM10, PM2.5, and PM1 and the results showed that PM2.5 took up about 90% of PM10 and PM1 accounted for about 68% of PM2.5, and BC aerosols are mainly present in fine particulates. The variability of BC concentrations is quite consistent between the Nancun station (141 m above sea level) and the Panyu station (13 m above sea level), which are 8 km apart from each other. The concentration in higher altitude station (Panyu) is consistently lower than the lower altitude station (Nancun), and the difference of annual mean is about 4 μg·m-3. | WU Dui MAO JieTai DENG XueJiao TIE XueXi ZHANG YuanHang ZENG LiMin LI Fei TAN HaoBo BI XueYan HUANG XiaoYing CHEN Jing DENG Tao | 2009 | Science China Earth Sciences2009，52，8： | 58 |
| 3 | Evolution of planetary boundary layer under different weather conditions,and its impact on aerosol concentrations显示文摘一个领域实验在天津被进行,从 2010 年 9 月 930 日的中国,在表面空气污染物质上集中了于行星的边界层(PBL ) 和它的影响的进化。实验使用了三台遥感仪器,风侧面雷达( WPR ),微波辐射计( MWR )和微脉搏的激光雷达( MPL ),到检测风,温度,和喷雾器 backscattering 系数并且到的垂直侧面测量表面污染物质的垂直侧面(喷雾器,公司, SO2 , NOx ),并且也从 255-m 收集了声音的风速表数据气象学的塔。把大小基于这些, PBL 的进化被估计。平均 PBL 高度在夜间期间在 noon/afternoon-time,和 200300 m 期间是大约 10001300 m。PBL 高度和喷雾器集中是相关反的在期间清楚并且薄雾条件。当平均喷雾器集中分别地是在薄雾和晴朗天空条件下面的 52 和 17 g/m3 时,平均最大的 PBL 高度是 1.08 和 1.70 km。太阳的放射上的喷雾器和云的影响基于从 255-m 收集的声音的风速表数据被观察气象学的塔。当 PBL 的镇压结构进一步削弱了污染物质的散开时,热流动被发现被薄雾(重污染) 或云显著地减少了,它趋于压抑 PBL 的发展,导致重污染。这个可能的积极反馈周期(更多的喷雾器降低 PBL 高度更多的喷雾器) 将在大城市为重地面污染导致一个加速过程。 | Jiannong Quan Yang Gao Qiang Zhang Xuexi Tie Junji Cao Suqin Han Junwang Meng Pengfei Chen Delong Zhao | 2013 | Particuology2013，11，1： | 51 |
| 4 | Aerosol pollution in China:Present and future impact on environment显示文摘With its dense population, rapid economic growth and dramatic rate of urbanization, China is experiencing extreme air pollution problems. This is particularly the case in Central-Eastern China (CEC), where the two major cities of Beijing and Tianjin are located, in the Yangtze-River Delta (YRD) with the city of Shanghai, and in the Pearl-River Delta (PRD) with the mega-city of Guangzhou. Space observations show that the atmospheric aerosol load in these three regions is considerably higher than, for example, in the urbanized regions of Europe and North America. The high aerosol concentrations in these regions have raised many environmental problems, such as impact on human health, visibility, and climate changes. In this paper, several crucial issues regarding aerosol pollution in these highly populated regions (CEC, YRD, and PRD) are discussed, including (1) when the aerosol load starts to rapidly increase in these regions; (2) how the high aerosol concentrations affects the environment; and (3) what the potential consequences are under possible low aerosol load in these regions. Discussion on these crucial issues might lead to some insight for better understanding of the characterizations of aerosol pollution due to the rapid economical development in China. | Xuexi Tie Junji Cao | 2009 | Particuology2009，7，6： | 48 |
| 5 | Effect of atmospheric aerosol on surface ozone variation over the Pearl River Delta region显示文摘Our analysis of the surface aerosol and ultraviolet(UV) measurements in Pearl River Delta(PRD) region shows that the sur-face UV radiation is reduced by more than 50% due to high aerosol concentrations.This has important impacts on urban eco-system 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 pa-rameters) 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 AOD550 nm≥0.6 and AOD340 nm≥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. | DENG XueJiao ZHOU XiuJi WU Dui TIE XueXi TAN HaoBo LI Fei BI XueYan DENG Tao JIANG DeHai | 2011 | Science China Earth Sciences2011，54，5： | 10 |
| 6 | Analysis of the causes of heavy aerosol pollution in Beijing,China:A case study with the WRF-Chem model显示文摘The causes and variability of a heavy haze episode in the Beijing region was analyzed.During the episode,the PM2.5 concentration reached a peak value of 450 μg/kg on January 18,2013 and rapidly decreased to100 μg/kg on January 19,2013,characterizing a large variability in a very short period.This strong variability provides a good opportunity to study the causes of the haze formation.The in situ measurements(including surface meteorological data and vertical structures of the winds,temperature,humidity,and planetary boundary layer(PBL)) together with a chemical/dynamical regional model(WRF-Chem) were used for the analysis.In order to understand the rapid variability of the PM2.5 concentration in the episode,the correlation between the measured meteorological data(including wind speed,PBL height,relative humidity,etc.) and the measured particle concentration(PM2.5 concentration) was studied.In addition,two sensitive model experiments were performed to study the effect of individual contribution from local emissions and regional surrounding emissions to the heavy haze formation.The results suggest that there were two major meteorological factors in controlling the variability of the PM2.5 concentration,namely,surface wind speed and PBL height.During high wind periods,the horizontal transport of aerosol particles played an important role,and the heavy haze was formed when the wind speeds were very weak(less than 1 m/s).Under weak wind conditions,the horizontal transport of aerosol particles was also weak,and the vertical mixing of aerosol particles played an important role.As a result,the PBL height was a major factor in controlling the variability of the PM_(2.5) concentration.Under the shallow PBL height,aerosol particles were strongly confined near the surface,producing a high surface PM_(2.5) concentration.The sensitivity model study suggests that the local emissions(emissions from the Beijing region only)were the major cause for the heavy haze events.With only local emissions,the calculated peak value of the PM_(2.5) concentration was 350 μg/kg,which accounted for 78%of the measured peak value(450 μg/kg).In contrast,without the local emissions,the calculated peak value of the PM_(2.5) concentration was only100 μg/kg,which accounted for 22%of the measured peak value. | Hui He Xuexi Tie Qiang Zhang Xiange Liu Qian Gao Xia Li Yang Gao | 2015 | Particuology2015，13，3： | 9 |
| 7 | Effects of two polybrominated diphenyl ethers(BDE-47,BDE-209) on the swimming behavior, population growth and reproduction of the rotifer Brachionus plicatilis显示文摘Polybrominated diphenyl ethers(PBDEs) are new kinds of persistent organic pollutants(POPs) and their potential threats to the equilibrium and sustainability of marine ecosystems have raised worldwide concerns. Here, two kinds of PBDEs, tetra-BDE(BDE-47)and deca-BDE(BDE-209) were applied, and their toxic effects on the swimming behavior,population growth and reproduction of Brachionus plicatilis were investigated. The results showed that:(1) The actual concentrations of BDE-47 and-209 in the seawater phase measured by GC–MS(Gas Chromatography-Mass Spectrometer) were much lower than their nominal concentrations.(2) In accordance with the 24-hr acute tests, BDE-209 did not show any obvious swimming inhibition to rotifers, but a good correlation did exist between the swimming inhibition rate and BDE-47 concentration suggesting that BDE-47 is more toxic than BDE-209.(3) Both BDE-47 and-209 had a significant influence on the population growth and reproduction parameters of B. plicatilis including the population growth rate, the ratio of ovigerous females/non-ovigerous females(OF/NOF), the ratio of mictic females/amictic females(MF/AF), resting egg production and the mictic rate, which indicate that these parameters in B. plicatilis population were suitable for monitoring and assessing PBDEs. Our results suggest that BDE-47 and-209 are not acute lethal toxicants and may pose a low risk to marine rotifers at environmental concentrations for short-term exposure. They also accumulate differently into rotifers. Further research data are needed to understand the mechanisms responsible for the effects caused by PBDEs and to assess their risks accurately. | Jingjing Sha You Wang Jianxia Lv Hong Wang Hongmei Chen Leilei Qi Xuexi Tang | 2015 | Journal of Environmental Sciences2015，27，2： | 9 |
| 8 | Evidence of vacuolar compartmentalization of arsenic in the hyperaccumulator Pteris vittata显示文摘Pteris vittata can hyperaccumulate arsenic (As) to >1% of its dry weight without showing any signs of toxicity, indicating the existence of effective plant-internal detoxification mechanisms. Although vacuolar compartmentalization is known to play an important role in heavy metal detoxification and tolerance, direct evidence of arsenic compartmentalization in this hyperaccumulator was lacking. Here we report the subcellular localization of As in the callus of P. vittata. The callus induced from gametophytes of P. vittata exposed to 0.2 mmol/L arsenate for 20 days were examined by directly isolating cell walls, protoplasts and vacuoles, and determining arsenic concentrations. Of the total As in the callus, about 94% was in the protoplast, and of that, 91% was present in the vacuoles, indicating that vacuoles are a major storage site for As in P. vittata. In addition, the changes in the chemical components of vacuoles were analyzed by Fourier transform infrared spectroscopy (FTIR). | YANG XueXi CHEN Hui DAI XiaoJing XU WenZhong HE ZhenYan MA Mi | 2009 | Chinese Science Bulletin2009，54，22： | 8 |
| 9 | Acute and chronic toxic effects of Pb^(2+)on polychaete Perinereis aibuhitensis:Morphological changes and responses of the antioxidant system显示文摘Perinereis aibuhitensis was used to assess adverse biological effects caused by acute and chronic Pb2+exposure in artificial seawater under controlled laboratory conditions. In 96-hr acute toxicity experiments,the morphological changes showed a positive time/dose-dependent tendency,and the 96-hr LC50 value of Pb2+was 686.41 mg/L. The responses of enzymatic and non-enzymatic antioxidants in tissues including catalase(CAT),peroxidase(POD),superoxide dismutase(SOD),glutathione peroxidase(GSH-PX),malondialdehyde(MDA) and the content of total soluble protein(TSP),were investigated on days 1,4,7 and 10 after Pb2+exposure under chronic toxicity testing. Results showed that the activation of the antioxidant system in P. aibuhitensis depended on the Pb2+concentration and the duration of exposure time.Specifically,POD and SOD activities were induced on the first day of the exposure and decreased to the control level on day 10 after exposure. Therefore,these two indexes could be used to indicate oxidative stress associated with P. aibuhitensis exposure to Pb2+. | Yulu Tian Hongjun Liu Qixiang Wang Jian Zhou Xuexi Tang | 2014 | Journal of Environmental Sciences2014，26，8： | 8 |
| 10 | Variability of SO_2 in an intensive fog in North China Plain:Evidence of high solubility of SO_2显示文摘一个地实验在在 11 月 5 日和 2009 年 11 月 8 日之间的一个集中的雾事件被进行,在在诺思中国平原(NCP ) 的一个重重地弄脏 SO2 的区域,到措施 SO2 和其它空气污染物质,雾微滴的液体水内容(LWC ) ,和另外的基本气象学的参数。在雾时期期间, SO2 的集中在雾微滴与 LWC 有关仔细显示出大可变性,它是。, SO2 的平均集中在雾时期期间在非雾时期期间是大约 25 ppbv,它很快归结为大约 47 ppbv。SO2 的如此的大减小建议由于 SO2 的高溶解度, SO2 (大约 70%80%) 的一个多数在雾微滴在水里从气体回复了到水的阶段。然而,到水的阶段变换的计算气体被仅仅使用亨利 SO2 的法律常数大部分低估,因此在雾微滴建议 SO2 的那水的反应可能在提高 SO2 的溶解度起某重要作用。简化现象,一个有效溶解度系数在这研究被建议。SO2 测量的这可变性在 NCP 在雾微滴,为在云的酸味的更好的理解的因此提供的重要含意,猛冲,和雾在广泛的雾事件期间提供 SO2 的氧化的直接证据,现在在中国的一个中央环境焦点由于它的快速的经济发展。 | Qiang Zhang Xuexi Tie Weili Lin Junji Cao Jiannong Quan Liang Ran Wanyun Xu | 2013 | Particuology2013，11，1： | 8 |
| 11 | Allelopathic growth inhibition of Heterosigma akashiwo by the three Ulva spcieces(Ulva Pertusa,Ulva Linza,Enteromorpha intestinalis) under laboratory conditions显示文摘Allelopathic effects of several concentrations of fresh tissue,dry powder and dry tissue of three bloom-forming green macroalgae Ulva pertusa,Ulva linza and Enteromopha intestinalis on the red tide microalga Heterosigma akashiwo were evaluated in microcosms systems.The effects of macroalgae culture medium filtrate were investigated on H.akashiwo using initial or semi-continuous filtrate addition.Preliminary studies on the algicidal effects of one aqueous and four organic solvent extracts from the macroalgae on the microalga were carried out to confirm the existence of allelochemicals in the tissue of these macroalgae.The dry powder of U.pertusa was extracted with methanol,and the methanol extracts were partitioned to petroleum ether phase,ethyl acetate phase,butanol phase and distilled phase by liquid-liquid fractionation.The bioassays of the activity of every fraction were carried out on H.akashiwo.The resultant microcosms assay showed that the growth of H.akashiwo was strongly inhibited by using fresh tissues,dry powder or dry tissue of these three macroalgae,while aqueous and methanol extracts of both macroalgae had strong inhibitory effects on the growth of H.akashiwo,and the EC 50 values for methanol extract of U.pertusa,U.linza or E.intestinalis were 0.016,0.028×10-12 or 0.033×10-12,respectively.While the other three organic solvent extracts(acetone,ether and chloroform) had no apparent effect on its growth,this suggests that the allelochemicals from these three macroalgae had relatively high polarities.The activity of petroleum ether phase,ethyl acetate phase,butanol phase and distilled phase of U.pertusa methanol extract was carried out on H.akashiwo indicating that petroleum ether phase and ethyl acetate phase had stronger algicidal effect on H.akashiwo.The inhibition effect of the ethyl acetate phase was not as strong as that of petroleum ether phase,and effective concentration of petroleum ether phase was 17 mg/L for H.akashiwo.However,no significant algicidal effects were observed on the butanol phase and distilled water phase.These three macroalgae's culture medium filtrate exhibited no apparent growth inhibitory effect on the microalga under initial filtrate addition whereas the growth of H.akashiwo was significantly inhibited under semi-continuous filtrate addition,which suggests that continuous release of small quantities of rapidly degradable allelochemicals from the fresh tissue of both macroalgae was effective in inhibiting the growth of H.akashiwo. | WANG Renjun FENG Lei TANG Xuexi WANG Jinhe DONG Shuanglin | 2012 | Acta Oceanologica Sinica2012，31，3： | 7 |
| 12 | Attenuation of ultraviolet radiation reaching the surface due to atmospheric aerosols in Guangzhou显示文摘The UV attenuation due to atmospheric aerosols in Guangzhou was quantitatively assessed using surface ultraviolet radiation (UV,295-385 nm) observation,sun photometer and radiation models.Observations showed that the annual average value of aerosol optical depth (AOD) was 1.19 in UV spectral region of 340 nm,the annual average occurrence frequency of aerosol optical depth AOD 340 nm >1.0 was 55%,and the annual average attenuation rate of surface UV direct radiation of 340 nm was 68%.It was proven in the observation of surface UV radiation and model evaluation that annual average attenuation of UV due to atmosphere was 75%,and that reached 72% in the dry season (October,November,December and January);while average attenuation of UV due to atmospheric aerosols reached 62% in the dry season.It was indicated that very significant UV attenuations due to atmospheric aerosols existed in Guangzhou urban agglomeration,and at least half of UV radiation was attenuated due to atmospheric aerosols.Such large-amplitude attenuation will have a significant impact on urban ecosystem and species chemical cycles,especially photochemical reaction processes. | DENG XueJiao ZHOU XiuJi TIE XueXi WU Dui LI Fei TAN HaoBo DENG Tao | 2012 | Chinese Science Bulletin2012，57，21： | 6 |
| 13 | Possible effects of climate change of wind on aerosol variation during winter in Shanghai,China显示文摘Several data sets were introduced to investigate the possible effects of climate-change-related variation of wind on aerosol concentration during winter in Shanghai,China.These data sets included the daily wind speed,wind direction,visibility,and precipitation from '1956 to 2010,hourly PM_(10) concentration from 2008 to 2010,and the NCEP/NCAR reanalysis data of global atmospheric circulation from 1956 to2010.The trend of aerosol concentration and its correlations with wind speed and wind direction in winter were analyzed.Results indicated that there was an increase in the number of haze days in winter of 2.1 days/decade.Aerosol concentration,represented by PM_(10) in this study,was highly correlated to both wind speed and direction in winter.The PM_(10) concentration increased as wind speed decreased,reaching maximum values under static wind conditions.The PM_(10) concentration was relatively lower under easterly winds and higher under westerly winds.The analysis showed that weaker East Asia winter monsoons have resulted in a reduction of wind speed,increase in static wind frequency,and decline in the frequency of northerly winds since the 1980 s.Moreover,the rapid expansion of urban construction in Shanghai has changed the underlying surface considerably,which has led to a reduction in wind speed.Finally,a wind factor was defined to estimate the combined effects of wind speed and wind direction on aerosol concentrations in Shanghai.The analysis of this factor indicated that changes in atmosphere circulation and urbanization have had important effects on the number of winter haze days in Shanghai. | Weidong Zhou Xuexi Tie Guangqiang Zhou Ping Liang | 2015 | Particuology2015，13，3： | 6 |
| 14 | Ultraviolet irradiation induced oxidative stress and response of antioxidant system in an intertidal macroalgae Corallina officinalis L.显示文摘The response of the antioxidant defense system of an intertidal macroalgae Corallina officinalis L.to different dosages of UV-B irradiation was investigated.Results showed that superoxide dimutase (SOD) and peroxidase (POX) increased and then maintained at a relatively stable level when subjected to UV-B irradiation.Catalase (CAT) activity under medium dosage of UV-B irradiation (Muv) and high dosage of UV-B irradiation (Huv) treatments were significantly decreased.Ascorbate peroxidase (APX) activity first remained unaltered and then increased in Huv treatment.In addition,the assay on isozymes was carried out using non-denaturing polyacrylamide gel electrophoresis (PAGE).The activities of some SOD isoforms were altered by UV-B.Two new bands (POX V and POX VII) appeared upon exposure to all three UV-B dosages.CAT III activity was increased by low dosage of UV-B irradiation (Luv),whereas CAT III and CAT IV disappeared when the alga was exposed to Muv and Huv.Two bands of APX (APX VI and APX VII) were increased and a new band (APX X) was observed under Huv exposure.H 2 O 2 and thiobarbituric acid reacting substance (TBARS) increased under Muv and Huv treatments.Overall,UV-B protection mechanisms are partly inducible and to a certain extent sufficient to prevent the accumulation of damage in C.officinalis. | Lixia Li Jiqiang Zhao Xuexi Tang | 2010 | Journal of Environmental Sciences2010，22，5： | 5 |
| 15 | Stable isotopic composition of otoliths in identification of stock structure of small yellow croaker(Larimichthys polyactis) in China显示文摘Oxygen and carbon isotope ratios(δ^(18)O and δ^(13)C) in otoliths were used to identify the stock structure of small yellow croaker,Larimichthys polyactis.Otoliths were collected from fish at five locations across the Yellow Sea and the Bohai Sea representing most of their distributional range and fisheries areas.The significant differences in the isotopic signatures showed that the five locations could be chemically distinguished and clearly separated,indicating stock subdivision.Correlation of δ^(18)O and δ^(13)C values suggested that population of L.polyactis could be divided into the Bohai Sea group,the southern Yellow Sea group and the central Yellow Sea group.Discriminant analysis of δ^(18)O and δ^(13)C values demonstrated a high significant difference with 85.7% classification accuracy.The spatial separation of L.polyactis indicated a complex stock structure across the Yellow Sea and the Bohai Sea.These results indicate that optimal fisheries management may require a comprehensive consideration on the current spatial arrangements.This study has provided further evidence that measurement of the stable isotopes ratios in otolith can be a valuable tool in the delineation of fishery management units. | WANG Yukun HUANG Jiansheng TANG Xuexi JIN Xianshi SUN Yao | 2016 | Acta Oceanologica Sinica2016，35，6： | 5 |
| 16 | Fabrication of aluminum matrix composite reinforced with carbon nanotubes显示文摘1.0wt.% carbon nanotube (CNT) reinforced 2024Al matrix composite was fabricated by cold isostatic press and subsequent hot extrusion techniques. The mechanical properties of the composite were measured by a tensile test. Mean-while,the fracture surfaces were examined using field emission scanning electron microscopy. The experimental results show that CNTs are dispersed homogeneously in the composite and that the interfaces of the Al matrix and the CNT bond well. Although the tensile strength and the Young’s modulus of the composite are enhanced markedly,the elongation does not decrease when compared with the matrix material fabricated under the same process. The reasons for the increments may be the extraordinary mechanical properties of CNTs,and the bridging and pulling-out role of CNTs in the Al matrix composite. | DENG Chunfeng ZHANG Xuexi MA Yanxia WANG Dezun | 2007 | Rare Metals2007，26，5： | 5 |
| 17 | Analysis of cultivable aerobic bacterial community composition and screening for facultative sulfate-reducing bacteria in marine corrosive steel显示文摘Anaerobic, aerobic, and facultative bacteria are all present in corrosive environments. However, as previous studies to address corrosion in the marine environment have largely focused on anaerobic bacteria, limited attention has been paid to the composition and function of aerobic and facultative bacteria in this process. For analysis in this study, ten samples were collected from rust layers on steel plates that had been immersed in seawater for diff erent periods (i.e., six months and eight years) at Sanya and Xiamen, China. The cultivable aerobic bacterial community structure as well as the number of sulfate-reducing bacteria (SRB) were analyzed in both cases, while the proportion of facultative SRB among the isolated aerobic bacteria in each sample was also evaluated using a novel approach. Bacterial abundance results show that the proportions are related to sea location and immersion time;abundances of culturable aerobic bacteria (CAB) and SRB from Sanya were greater in most corrosion samples than those from Xiamen, and abundances of both bacterial groups were greater in samples immersed for six months than for eight years. A total of 213 isolates were obtained from all samples in terms of CAB community composition, and a phylogenetic analysis revealed that the taxa comprised four phyla and 31 genera. Bacterial species composition is related to marine location;the results show that Firmicutes and Proteobacteria were the dominant phyla, accounting for 98.13% of the total, while Bacillus and Vibrio were the dominant genera, accounting for 53.06% of the total. An additional sixfacultative SRB strains were also screened from the isolates obtained and were found to encompass the genus Vibrio (four strains), Staphylococcus (one strain), and Photobacterium (one strain). It is noteworthy that mentions of Photobacterium species have so far been absent from the literature, both in terms of its membership of the SRB group and its relationship to corrosion. | LI Xiaohong XIAO Hui ZHANG Wenjun LI Yongqian TANG Xuexi DUAN Jizhou YANG Zhibo WANG Jing GUAN Fang DING Guoqing | 2019 | Journal of Oceanology and Limnology2019，37，2： | 4 |
| 18 | Effect of UV-B Radiation on Ingesting and Nutritional Selecting Behavior of Rotifer Brachionus urceus显示文摘Effect of UV-B radiation on ingesting and nutritional selecting behavior of the roifer Brachionus urceus on 5 species of micro-algae were studied under controlled laboratory conditions. Results showed that enhanced UV-B radiation significantly inhibited ingesting of the rotifer B. urceus when it was fed with 5 species of micro-algae (p<0.05). The ingesting selectivity rate varied with the UV-B radiation enhancement when it was fed with 5 species micro-algal mixture. Results indicated that the enhanced UV-B radiation could affect ingesting and nutritional selectivity of B. urceus. | FENG Lei TANG Xuexi WANG You XIAO Hiu MENG Xianghong CHEN Xiguang | 2007 | Wuhan University Journal of Natural Sciences2007，12，2： | 4 |
| 19 | Grain size distribution at four developmental stages of crescent dunes in the hinterland of the Taklimakan Desert,China显示文摘Although scientists have performed many studies on crescent (barchan) dunes in the Taklimakan Desert,few studies reported the changes in grain size at different development stages of crescent dunes.In order to evaluate the changing trends of surface sediment grain size with dune development,we investigated the grain size characteristics at four developmental stages (oval sand pile,shield dune,incipient crescent dune and mature crescent dune) of crescent dunes by measuring the morphology of sand dune and observing the near-surface wind regime.The dunes have developed in a wide inter-dune corridor between high compound longitudinal ridges in China's Taklimakan Desert.The surface sediments at four developmental stages of the crescent dunes were primarily composed of fine sands,followed by very fine and medium sands.Mean grain sizes ranged from 2.8 to 3.1 φ,with a unimodal distribution.The sands were moderately well-sorted,their distribution varied from platykurtic to very platykurtic,and symmetrical or skewed towards the fine particles.From oval sand piles through shield and incipient crescent dunes to mature crescent dunes,incipient grain size gradually increased,particles became finer,sorting became better,kurtosis and skewness increased.Grain sizes on the surface layer became coarser upwards from the toe of the windward slope and then became finer towards the bottom of the leeward slope.We found that the coarsest particles at different positions at the four developmental stages were different.The coarsest particles were distributed at the top of the oval sand piles and shield dunes,versus at the middle of the windward slope of the incipient and mature crescent dunes.Correlations between the mean grain size and other grain size parameters showed that as mean grain size became finer,sorting became better and kurtosis became wider,but skewness changed only slightly.In addition,grain size variation in the surface sediments correlated with the movement speed of the dunes in the study area.In the open ground among tall-complex longitudinal ridges in the hinterland of the Taklimakan Desert where aeolian environment is characterized by comparatively strong wind and unsaturated sand flow,faster dune movement corresponded to coarser grain size. | JIA Wenru ZHANG Chunlai LI Shengyu WANG Haifeng MA Xuexi WANG Ningbo | 2016 | Journal of Arid Land2016，8，5： | 4 |
| 20 | Effect of UV-B radiation on the feeding behavior of the rotifer Brachionus plicatilis显示文摘Effect of UV-B radiation on the feeding behaviour of marine zooplankton is important to assessing the health harm of marine ecosystem due to the gradually enhanced UV-B radiation in air. However, there are a few studies on this topic. The feeding behavior of the rotifer, Brachionus plicatilis, under the treatment of UV-B radiation on five species of microalgae, i.e., Chlorella sp., Tetraselmis chuii, Isochrysis galbana Park 8701, Chaetoceros muelleri Lermumerman, and Nitzschia clostertum, was studied. The results showed that the filtering and feeding rates of the rotifer decreased significantly with the dose increase of UV-B radiation when fed with five species of microalgae respectively (P<0.05) which indicates UV-B radiation inhibits the feeding activities of the rotifer on microalage. The mixed culture experiments shows the rotifer preferred to feed Chlorella sp., then C. muelleri,I. galbana, N. clostertum and T. chuii in turn if without UV-B radiation. Under the highest dose of UV-B radiation treatment (2.70 kJ/m2), the rotifer preferred to feed C. muelleri, then Chlorella sp., N. clostertum, I. galbana and T. chuii in turn. Chlorella sp., I. galbana and C. muelleri became the more favorite foods of the rotifer while T. chuii and N. clostertum became less favorite foods. The change of feeding rate and feeding selectivity of zooplankton driven by the enhanced UV-B radiation will lead to the change in the structure of phytoplankton community. | FENG Lei LI Xin WANG Jinhe HAN Honglei TANG Xuexi CHEN Xiguang | 2007 | Acta Oceanologica Sinica2007，26，4： | 4 |
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