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1Coral reefs in the South China Sea:Their response to and records on past environmental changes显示文摘This paper reviews both the recent and longer-term(Holocene) ecological history of coral reefs in the South China Sea(SCS).(1) Local ecological monitoring since the 1960s shows that the coral reefs in the South China Sea have declined dramatically,reflecting the rapid decrease of living coral cover and the great loss of symbiotic zooxanthellae.Collectively,this has led to a significant decrease of annual CaCO3 production.Heavy anthropogenic activities and global warming are recognized as major triggers of the observed coral reef degradation.Observations show that the modern coral reefs in the SCS are a source of at-mospheric CO2 in summer.(2) Coral reefs of the SCS have been widely used to reveal longer-term environmental variations,including Holocene high-resolution sea surface temperature(SST) and abrupt climate events,millennial-scale El Nio varia-tions,millennial-and centennial-scale sea level oscillations,strong and cyclic storm activities,East Asian monsoon intensities,variation in seawater pH,and recent seawater pollution.(3) Coral reefs of the southern SCS have experienced repeated epi-sodes of bleaching over the last 200 years due to high SST and intense El Ni o events;coral reefs of the northern SCS suffered high levels of mortality during several abrupt winter cold-water bleaching events during the middle Holocene warm period.On average,recovery after the middle Holocene cold-bleaching took 20-30 years;recovery following other middle Holocene en-vironmental stresses took approximately 10-20 years.Such findings have significantly contributed to the understanding of the present ecological pressures faced by the coral reefs in the SCS,the histories of Holocene climate/environment changes,and the long-term models of coral reef responses to various past environmental changes.YU KeFu 2012Science China Earth Sciences2012,55,8:41
2Twenty-five years of change in scleractinian coral communities of Daya Bay (northern South China Sea) and its response to the 2008 AD extreme cold climate event显示文摘世界范围的珊瑚礁石逐渐地正在变得并且有害地影响在之上由包括的许多因素,重要气候变化,例如全球温暖和增加的 El Nino 南部的摆动活动。通常,珊瑚礁石的坚持,在特别低纬度,部分地,海运被管理不超过集体死亡能在发生的批评限制(∼30 ° C ) 的表面温度。因此,它被想珊瑚那生活在高纬度(即,当前更凉爽的海表面温度) 将多半比珊瑚生活在对假设未来温度增加更有利作出回应低纬度(即,当前更温暖的海表面温度) 。因而,高纬度的珊瑚社区可以有潜力在面临潜在的未来时为许多珊瑚种类充当 refugia 的区域全球温暖。Daya 海湾(22 ° 3 1 ′22 ° 5 0 ′N ) ,北华南海,包含几个高纬度的 non-reefal 珊瑚社区并且在这个区域以内代表 scleractinian 珊瑚的最在北方的分布之一。显著地, Daya 海湾经历了在整个过去的 50 年的在空和海表面温度中的戏剧的温暖。在这篇论文,我们在 Daya 海湾珊瑚社区分析 25 年变化,把两个基于历史性的调查并且我们的最近 2006 2008 地区性的生态的调查。我们的结果建议与预言相反,在过去的 25 年期间在在 Daya 海湾以内的珊瑚盖子有重要衰落(即,在到在 2008 的 15.3% 仅仅珊瑚盖子的 1983/1984 的 76.6% 珊瑚盖子) 。如此的变化也在最丰富的珊瑚种类反映重要移动,从 Acropora pruinosa 到 Favites abdita。大多数现代珊瑚社区变得以前在 15 和 30 年之间建立了,相应于增加的冬季海表面温度的一个时期。然而,很少的殖民地变得在最后 15 年以内建立了,尽管有温暖的一个更强烈的时期。由考虑另外的因素,我们假设那直接人为的影响,而非气候的事件,限制了发展,并且驾驶了衰落,最后 15 年里的 Daya 海湾珊瑚社区。Daya 海湾也在过去的 50 年期间受到了偶尔的极端冷事件,与最近的发生在 2008 年初(13 年 1 月 13 日 2 月) 。在 2008 冷事件期间,最低空气温度到达仅仅 6.6 ° C,和吝啬的海表面温度 2 月秋天,包括在 12.3 ° C 的六连续的天 < 14 ° C。显著地,海表面温度在通常在 scleractinian 珊瑚社区导致集体死亡的假设批评更低的温度阀值(∼13 ° C ) 下面掉落。令人惊讶地,我们的珊瑚社区调查,以前进行了两个(2007 年 8 月) 并且在以后(2008 年 2 月下旬) 极端 2008 冷事件,证明 Daya 海湾珊瑚生态系统恰好被影响在之上在冷时期期间。那些观察建议 Daya 海湾 scleractinian 珊瑚社区开发了改编到低海表面温度。总的来说,我们的数据支持高纬度的珊瑚社区例如 Daya 海湾,有的假设在潜在的未来的来临为 scleractinian 珊瑚充当 refugia 的区域的潜力全球温暖。CHEN TianRan YU KeFu SHI Qi LI Shu Gilbert J. Price WANG Rong ZHAO MeiXia CHEN TeGu ZHAO JianXin 2009Chinese Science Bulletin2009,54,12:22
3Assessment of coral bleaching using symbiotic zooxanthellae density and satellite remote sensing data in the Nansha Islands,South China Sea显示文摘Coral bleaching,characterized by a significant loss of symbiotic zooxanthellae,is the primary cause of mass coral mortality and reef degradation throughout the world.The characteristics,processes,and resistance of corals to bleaching varies significantly and is dependent on environmental conditions.We documented a mass coral bleaching event in June 2007 at the Meiji and Zhubi Reefs,Nansha Islands (NS),South China Sea using ecological surveys and measurement of coral zooxanthellae density and sea surface temperatures (SST).More than 35 species of corals (between 0-20 m in depth) were bleached.These bleached corals accounted for 15.6% of total corals in the investigated quadrats.The branching corals Pocillopora and Acropora were the most vulnerable species whereas the massive corals Porites and Favia were more tolerant of the high SSTs.Surprisingly,we found no evidence of bleaching in Agariciidae corals suggesting that this family is resistant to thermal stresses.The bleached corals had lost 72%-90% of their symbiotic zooxanthellae.Furthermore,corals that had no visual signs of bleaching had also lost 31%-53% of their zooxanthellae suggesting that most corals were experiencing the early stage of bleaching.The monthly mean SST during June 2007 was 30.8°C,the highest since 1998.Based on measurements of SST and the Hotspots and DHW data (NOAA),we conclude that it the extremely high SSTs triggered this coral bleaching event.Our results suggest that the previously accepted temperature thresholds used to predict coral bleaching based on satellite data are likely to underestimate the extent and intensity of coral bleaching,at least in the NS.LI Shu,YU KeFu,CHEN TianRan,SHI Qi & ZHANG HuiLing CAS Key Laboratory of Marginal Sea Geology,South China Sea Institute of Oceanology,Chinese Academy of Sciences Guangzhou 510301,China 2011Chinese Science Bulletin2011,56,10:15
4Interspecies and spatial diversity in the symbiotic zooxanthellae density in corals from northern South China Sea and its relationship to coral reef bleaching显示文摘珊瑚礁石漂白被共生 zooxanthellae, zooxanthellae 色素沉着的损失,或两个的逐出通常描绘。我们收集了分别地,在海南岛的 Sanya 和广东省的 Daya 海湾从 Luhuitou 和 Xiaodonghai 包括礁石大楼珊瑚的 21 个类的 39 种类的 128 件样品并且分析了共生 zooxanthellae 人口密度。结果显示出那:( 1 )共生 zooxanthella 密度从 0.67x10 ( 6 )变化,显示 8.48x10 ( 6 )房间/厘米( 2 )重要内部种可变性,与通常相对有更少的 zooxanthellae 的分支珊瑚(从 0.67x10 ( 6 ) 到 2.47x10 ( 6 )房间/厘米( 2 ))比巨大的种类(从 1.0x10 ( 6 )到 8.48x10 ( 6 )房间/厘米( 2 ));(2 ) 在 4 m 水深度以内住在的珊瑚比那些生活在底部有共生 zooxanthellae 的高水平(类似于 7 m 深度) 礁石区域;(3 ) 在在从相对高的纬度 Daya 海湾的珊瑚之间的 zooxanthellae 密度没有可辨别的差别(类似于 22 度 N ) 并且那些从相对低的纬度 Sanya (类似于 18 度 N ) 在可比较的海表面温度(SST ) ;(4 ) 在里面部分 -- 漂白珊瑚, zooxanthellae 的密度显示出下列顺序:看似健康的部分 > 漂白半的部分 > 漂白部分。基于上述结果,我们建议(1 ) 分叉之间的 zooxanthellae 密度差别和巨大的珊瑚种类是分叉的珊瑚对比巨大的珊瑚漂白更脆弱的主要原因。例如,共生 zooxanthellae 层次在分叉的 Acropora 和 Pocillopora 珊瑚并且这样是低的这些珊瑚更产生漂白和死亡;(2 ) 共生 zooxanthellae 密度能被环境条件也影响,例如沉积负担,潜水相关的混浊,和水产业相关的硝酸盐和磷酸盐输入,并且他们的增加可以在珊瑚减少共生 zooxanthellae 密度。LI Shu YU KeFu SHI Qi CHEN TianRan ZHAO MeiXia ZHAO JianXin 2008Chinese Science Bulletin2008,53,2:12
5The high-resolution climate recorded in the δ^(18)O of Porites lutea from the Nansha Islands of China显示文摘A Porites lutea core from Yongshu Reef of Nansha Islands covering 50 years growth history was ana-ly/ed for oxygen isotopic composition with monthly and seasonally resolution. The calibration of the δ18O with the instrumental temperature indicated that the coral δ18O is a good indicator for sea surface temperature (SST) and air temperature (t). It can be used to reconstruct the SST and air temperature of the Yongshu Reef sea area. In addition, the coral δ18O provides signatures for the intensity of the East Asia monsoon and it is a record for the activities of El Nino events. With the calibrated SST and air temperature formulas, the most recent fifty years SST and air temperature were reconstructed based on the coral δ18O, thus back up the understanding of the climate of Nansha Islands to 1950. far beyond the limit of the instrumental recording since September 1988. It was found that, in general, increasing 1℃ air temperature results in 0.24‰decrease in skeletal δ18O.YU Kefu, CHEN Tegu, HUANG Dingcheng, ZHAO Huanting, ZHONG Jinliang & LIU Dongsheng (LIU Tungsheng)South China Sea Institute of Oceanoiogy, Chinese Academy of Sciences. Guangzhou 510301, China:Geology and Geophysics Institute. Chinese Academy of Sciences, Beijing 100029, China 2001Chinese Science Bulletin2001,46,24:10
6Effect of thermal cycling on the mechanical properties of Zr_(41)Ti_(14)Cu_(12.5)Ni_(10)Be_(22.5) alloy显示文摘The effect of thermal cycling treatment on mechanical properties and thermal stability of a Zr41Ti14Cu12.5Ni10Be22.5 bulk metallic glass is investigated.The metallic glassy samples are sealed into quartz tubes under high vacuum condition,and liquid nitrogen together with electric furnace are used to control a periodical temperature variation between 196℃ and 150℃.The structure and properties of the tested samples for different thermal cycles have been examined by X-ray diffraction analysis,mechanical properties measurement and thermal analysis.It has been found that the structure and properties of the samples do not show a significant change even after 200 cycles,which suggests Zr41Ti14Cu12.5Ni10Be22.5 alloy as having potential in aerospace environment.WANG Xin SHAO Yang GONG Pan YAO KeFu 2012Science China(Physics,Mechanics & Astronomy)2012,55,12:10
7Estimate of carbonate production by scleractinian corals at Luhuitou fringing reef,Sanya,China显示文摘Carbonate production by scleractinian corals not only maintains coral reef growth, but also represents an important source of atmospheric carbon dioxide. In this paper the carbonate production by scler-actinian corals at Luhuitou fringing reef, Sanya, Hainan Island, China, is investigated with an ecological census-based method. Averaged carbonate production is 1.16 ± 0.55 kg·m-2·a-1 and 3.52 ± 1.32 kg·m-2·a-1 on the reef flat and reef slope, respectively, depending on the composition and distribution of corals and the intergeneric difference of skeletal growth. In response to the rapidly increasing human impacts, coral carbonate production has decreased by 80%―89% at this fringing reef since the 1960s; as a result, the reef accretion rate declined and became lower than the rate of sea level rise. Further development of the Luhuitou fringing reef will switch significantly from lateral extension sea-wards to vertical growth, reflecting a response of coral reef biogeomorphic process to strong human impacts under the background of global sea level rise. In addition, decrease in coral carbonate production reduced CO2 release from this fringing reef. In the future, it is likely that the role played by coral reefs, especially of fringing reefs, in the ocean and even in the global carbon cycle will be modified or weakened by the increasing human impacts.SHI Qi ZHAO MeiXia ZHANG QiaoMin YU KeFu CHEN TianRan LI Shu WANG HanKui 2009Chinese Science Bulletin2009,54,4:7
8Enhanced orange emission by doping CeB_6 in CaAlSiN_3:Ce^(3+) phosphor for application in white LEDs显示文摘A series of CeB6-doped and CeO_2-doped Ca_(1-x)SiAlN_3:xCe3+(denoted as CASN:Ce3+@CeB6 and CASN:Ce3+@CeO_2, respectively) were synthesized by alloy-nitridation method under high-purity nitrogen atmosphere. The morphologies, crystal phases, and luminescence properties were investigated in detail.With an increase in the concentration of CeB_6, the unit cell volume of CASN:Ce3+@CeB_6 slightly increases due to the substitution between ions, which leads to a change of micro structure around Ce3+. CASN:Ce3+@CeB6 efficiently emits yellow-orange light with a maximum emission intensity at around 550 nm for the content x of 0.01(being in comparable situation, CASN:Ce3+@CeO_2 is x = 0.04) when excited at460 nm. Compared with CASN:Ce3+@CeO_2, the red emission component of Ce3+ in CASN:Ce3+@CeB6 is much stronger. This is ascribed to energy transfer of intra-Ce3+(within one Ce3+ ion) and inter-Ce3+(between Ce3+ and Ce3+ ions). In addition, the replacements of N3-(0.132 nm for CN = 4) and O^(2-)(0.124 nm for CN = 4) by B^(2-)(0.140 nm for CN = 4), which can lead to a marked expansion of the host lattice and a decrease of the oxidation of samples, are also responsible for the increase of red emission component. Furthermore, CASN:Ce3+@CeB_6 phosphor has an excellent thermal stability because of the partial substitution of Ce-O(Ce-N) bonds by more covalent Ce-B. As a result, the outstanding luminescent properties of CASN:Ce3+@CeB6 phosphor make it practical to use in the single phosphor-coated high-color-rendering power white LED.Wenjie Wu Kefu Chao Wenquan Liu Lesi Wei Dahai Hu Taiyang Wang O. Tegus 2018Journal of Rare Earths2018,36,12:6
9Work toughening effect in Zr_(41)Ti_(14)Cu_(12.5)Ni_(10)Be_(22.5) bulk metallic glass显示文摘Work hardening is a well-known phenomenon occurring in crystalline metals during deformation,which has been widely used to increase the strength of metals although their ductility is usually reduced simultaneously. Here we report that the plastic strain of Zr41Ti14Cu12.5Ni10Be22.5 (at.%) bulk metallic glasses has been increased from 0.3% for the as-cast sample to 2.5%-8.0% for samples that have experienced pre-deformation under constrained conditions. The pre-deformed glassy alloys possess more free volume and abundant introduced shear bands,which are believed to promote the activation of shear bands in post-deformation and result in an increase in plasticity. The orientation of the pre-introduced shear bands relative to the loading direction will affect the deformation behavior of pre-deformed samples. The present results show that pre-deformation of this glassy alloy will result in work toughening. This work toughening effect can be removed by isothermal annealing at a sub-Tg (glass transition) temperature,which causes annihilation of free volume and healing of shear bands.QIU ShengBao GONG Pan YAO KeFu 2011Chinese Science Bulletin2011,56,36:6
10Ti-Zr-Be-Fe quaternary bulk metallic glasses designed by Fe alloying显示文摘A series of Ti-Zr-Be-Fe bulk metallic glasses(BMGs)with good glass-forming ability(GFA)and high specific strength have been developed.With different alloying routes and content of Fe,it is found that these alloys exhibit different GFA and mechanical properties.The effects of Fe addition on the GFA and mechanical properties of Ti-Zr-Be alloy are systemically investigated.The possible mechanisms for the improvement or damage to the GFA by addition of Fe can be interpreted in view of the mixing enthalpy,atomic size differences and electronegativity differences of the alloys,while the mechanical properties strongly depend on the Poisson’s ratio and free volume concentration.The experimental results also show that alloying technology is an effective method to improve the GFA and mechanical properties of Ti-Zr-Be glassy alloy.GONG Pan WANG Xin SHAO Yang CHEN Na YAO KeFu 2013Science China(Physics,Mechanics & Astronomy)2013,56,11:6
11Coral reef ecosystems in the South China Sea as a source of atmospheric CO_2 in summer显示文摘由空至海的 CO2 的领域大小在华南海的三个珊瑚礁石区域交换(即 Nansha 岛的 Yongshu 礁石环礁,南部的华南海(SCS ) ;Xisha 岛的 Yongxing 岛,北方中央的 SCS;并且在海南岛的 Sanya 的 Luhuitou Fringing 礁石,北 SCS ) 在 2008 和 2009 的夏天期间揭示了那 CO2 (pCO2 ) 的部分压力显示出的空气和表面海水常规日报周期。最小的价值在早上发生在晚上和最大的价值。在每三个学习区域的空气 pCO2 出现了小日报变化,当时大日报变化在海水 pCO2 被观察。日报海水 pCO2 的变化振幅是 70 摩尔摩尔? 1 在 Yongshu 礁石泻湖, 420619 摩尔摩尔? 1 在 Yongxing 岛礁石公寓,和 264579 摩尔摩尔上? 1 在 Luhuitou Fringing 礁石的礁石公寓上,并且 324492 摩尔摩尔? 1 在就在这 fringing 礁石外面的一个邻近的区域。关于空间关系,在越过华南海的由空至海的 CO2 流动有大差别(例如 0.4 mmol CO2 m ? 2 d ? 1 在 Yongshu 礁石, 4.7 mmol CO2 m ? 2 d ? 1 在 Yongxing 岛,并且 9.8 mmol CO2 m ? 2 d ? 1 在 Luhuitou Fringing 礁石)。然而,这些积极的值建议 SCS 的珊瑚礁石生态系统可以是到空气的 CO2 的网络来源。另外的分析显示了那日报在浅水礁石公寓的表面海水 pCO2 的变化主要被生物新陈代谢的过程控制,当那些被两个生物新陈代谢和水动力学因素更深的水泻湖和外部礁石区域调整时。不同于开的海洋,无机的新陈代谢在在珊瑚礁石生态系统影响海水 pCO2 变化起一个重要作用。YAN HongQiang YU KeFu SHI Qi TAN YeHui ZHANG HuiLing ZHAO MeiXia LI Shu CHEN TianRan HUANG LingYing WANG PinXian 2011Chinese Science Bulletin2011,56,7:6
12Two centuries-long records of skeletal calcification in massive Porites colonies from Meiji Reef in the southern South China Sea and its responses to atmospheric CO_2 and seawater temperature显示文摘SHI Qi YU KeFu CHEN TianRan ZHANG HuiLing ZHAO MeiXia YAN HongQiang 2012Science China Earth Sciences2012,55,1:6
13Receptor role of membrane bound macrophage colony-stimulating factor显示文摘According to the definition of cytokine, the direction of signaling should be from cytokine to receptor. The counter receptor was presented. Membrane bound macrophage colony-stimulating factor (m-M-CSF) and its receptor (M-CSF-R) were shown in human leukemic cell line J6-1 as autojuxtacrine mechanism. Soluble M-CSF receptor (sM-CSF-R), which was isolated from J6-1 cells membrane, was added into J6-1 cell culture. It was observed inhibition of J6-1 cell proliferation, decreasing of mitosis index and ratio of multinuclear cells, enlargement of cell diameter and volume, down regulation of numerous surface antigens. Dramatic change of intracellular pH was shown between several min to 20 min after treatment of sM-CSF-R. It suggested that some information was transmitted via m-M-CSF from sM-CSF-R. This counter signaling was not influenced by saccharification of m-M-CSF.Wu Kefu He Zhihong Zheng Guoguang Rao Qing Wang Xin 1998Chinese Science Bulletin1998,43,12:5
14Type-2 Fuzzy Control for Driving State and Behavioral Decisions of Unmanned Vehicle显示文摘In this paper, interval type-2 fuzzy sets, fuzzy comprehensive evaluation and the fuzzy control rules are synthesized to realize the control of unmanned vehicle in driving state and behavioral decisions. Compared to the type-1 fuzzy set, type-2 fuzzy sets have more advantages in handling the model based on uncertainties, linguistic information because the membership functions are fuzzy sets. Different membership functions are established for each factor when the unmanned vehicle is driving at different speed intervals. In addition, a new evaluation method is developed to analyze unmanned vehicle’s driving state. Finally, a set of dynamic fuzzy rules are sorted out, which can be applied to the unmanned vehicle’s behavioral decision-making and provide a new idea to related research.Xuanming Zhao Hong Mo Kefu Yan Lingxi Li 2020IEEE/CAA Journal of Automatica Sinica2020,7,1:5
15A bulk metal/ceramic composite material with a cellular structure显示文摘A bulk metal/ceramic composite material with a honeycomb-like micro-cell structure has been prepared by sintering the spherical Al90Mn9Ce1 alloy powders clad by Al2O3 nano-powder with the spark plasma sintering (SPS) technique. The as-prepared material consists of Al90Mn9Ce1 alloy cell and closed Al2O3 ceramic cell wall. The diameter of the cells is about 20―40 μm, while a thickness of the cell wall is about 1―2 μm. The ultimate compressive strength of the as-sintered materials is about 514 MPa, while its fracture strain is up to about 0.65 %. This composite material might possess good anti-corrosion, thermal endurance and other potential properties due to its unique microstructure. The result shows that the Al90Mn9Ce1/Al2O3 composite powders can be sintered by spark plasma sintering technique despite the large difference in their sintering temperature. This work offers a way of designing and preparing metal/ceramic composite material with functional property.ZHAO Zhankui YAO Kefu LI Jingfeng 2006Chinese Science Bulletin2006,51,2:5
16New materials of the steppe mammoth, Mammuthus trogontherii, with discussion on the origin and evolutionary patterns of mammoths显示文摘Recently found materials indicate that the steppe mammoth, Mammuthus trogontherii, survived in northern China into the late Pleistocene. East Asia is the key area of mammoth evolution after the initial radiation of early forms out of Africa and into Eurasia at the beginning of the late Pliocene (c. 3.5–3.0 Ma). M. rumanus, M. meridionalis, M. trogontherii, and M. primige- nius probably formed a continuous and transitional evolutionary lineage within the pan-Eurasian mammoth radiation in East Asia. Each speciation event of the Eurasian mammoths was followed by a rapid and large-scale dispersal event: out of East Asia. Allopatric speciation is the main speciation pattern of Mammuthus. The climatic vacillation was severe and frequent in East Asia from the early part of early Pleistocene (c. 2.6 Ma) onward, which probably brought about successive speciation in East Asia and the subsequent dispersal of the mammoths.WEI GuangBiao HU SongMei YU KeFu HOU YaMei LI Xin JIN ChangZhu WANG Yuan ZHAO JianXin WANG WenHua 2010Science China Earth Sciences2010,53,7:4
17Nanorattle Au@PtAg encapsulated in ZIF-8 for enhancing CO2 photoreduction to CO显示文摘Imidazolate-based ZIF-8 catalysts M@ZIF-8 (M = Au NR, Au@Ag NR, or Au@PtAg NRT;NR = nanorod, NRT = nanorattle), were assembled. Au NRs acted as the core for the epitaxial growth of the Ag shell, and oxidative etching of Au@Ag NRs led to Au@PtAg NRTs with K2PQI4 aqueous soluti on. All metal nano rods (MNRs) and metal nano rattles (MNRTs) were well dispersed and fully en capsulated in ZIF-8. Au @ PtAg NRTs encapsulated in ZIF-8 could lead to enhanced stability and selectivity for catalytic applications, combining the advantages of ZIF-8 (tailorable porosity) with the high surface area and improved optical sensitivity of rod-shaped NRTs. The catalyst Au @ PtAg@ZIF-8 exhibited efficient catalytic activity and CO selectivity for the gas-phase photoreduction of CO2 with H2O.Yuqun Su Haitao Xu Jiajia Wang Xikuo Luo Zhen-liang Xu Kefu Wang Wenzhong Wang 2019Nano Research2019,12,3:4
18Testing coral paleothermometers(B/Ca, Mg/Ca, Sr/Ca, U/Ca and δ^(18)O) under impacts of large riverine runoff显示文摘Sea surface temperature(SST) proxies including B/Ca, Mg/Ca, Sr/Ca, U/Ca and δ18O were analyzed in the skeleton of a Porites coral collected from the Zhujiang River(Pearl River) Estuary(ZRE). These geochemical proxies are influenced by river runoff and this area of the northern South China Sea is strongly affected by seasonal freshwater floods. We assessed the robustness of each SST proxy through comparison with the local instrumental SST. Coral Sr/Ca shows the highest correlation with SST variations(r2=0.59), suggesting Sr/Ca is the most robust SST proxy. In contrast, coral δ18O(r2=0.46), B/Ca(r2=0.43) and U/Ca(r2=0.41) ratios were only moderately correlated with SST variations, suggesting that they are disturbed by some other factors in addition to SST. The poor correlation(r2=0.27) between SST and Mg/Ca indicates that Mg/Ca in coral skeletons is not a simple function of SST variations. This may ultimately limit the use of Mg/Ca as a coral paleothermometer.CHEN Tianran YU Kefu ZHAO Jianxin YAN Hongqiang SONG Yinxian FENG Yuexing CHEN Tegu 2015Acta Oceanologica Sinica2015,34,8:4
19Non-thermal plasma treatment of Radix aconiti wastewater generated by traditional Chinese medicine processing显示文摘The wastewater effluent from Radix aconiti processing, an important step in the production processes of traditional Chinese medicine(TCM), is a type of toxic wastewater and difficult to treat. Plasma oxidation methods have emerged as feasible techniques for effective decomposition of toxic organic pollutants. This study examined the performance of a plasma reactor operated in a dielectric barrier discharge(DBD) to degrade the effluent from R. aconiti processing. The effects of treatment time, discharge voltage, initial p H value and the feeding gas for the reactor on the degradation of this TCM wastewater were investigated. A bacterium bioluminescence assay was adopted in this study to test the toxicity of the TCM wastewater after non-thermal plasma treatment. The degradation ratio of the main toxic component was 87.77% after 60 min treatment with oxygen used as feed gas and it was 99.59% when the initial p H value was 8.0. High discharge voltage and alkaline solution environment were beneficial for improving the degradation ratio. The treatment process was found to be capable of reducing the toxicity of the wastewater to a low level or even render it non-toxic. These experimental results suggested that the DBD plasma method may be a competitive technology for primary decomposition of biologically undegradable toxic organic pollutants in TCM wastewater.Yiyong Wen Jianping Yi Shen Zhao Song Jiang Yuming Chi Kefu Liu 2016Journal of Environmental Sciences2016,28,6:4
20Pd-Si binary bulk metallic glass显示文摘Pd80+xSi20-x (x=0,1,and 2) binary metallic glasses with the diameter ranging from 7 to 8 mm were prepared by a combination of fluxing and water quenching or air cooling. Thermal analysis results show that with increasing Si content,the glass transition temperature Tg,the initial crystallization temperature Tx and the onset crystalliza-tion temperature Tp of Pd-Si binary glassy alloys increase. Moreover,the super-cooled liquid region reaches 61 K. It indicates that Pd-Si binary alloys possess large glass forming ability,which can be greatly improved by fluxing treatment.YAO KeFu CHEN Na 2008Science China(Physics,Mechanics & Astronomy)2008,51,4:3
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