摘要-淀粉体运动微流变分析研究植物根的重力感应机制

利用淀粉体作为天然微探针,发展了模型植物拟南芥小柱细胞(感重细胞)中的活体微流变方法,分别对野生型拟南芥和肌动蛋白细胞骨架突变体进行微流变分析

ACCUMULATION AND DYNAMICS of Cu,Pb,Zn AND Mn ELEMENTS IN KANDELIA CANDEL(L.) DRUCE MANGROVE COMMUNITY of JIULONG RIVER ESTUARY of FUJIAN

探讨福建九龙江口秋茄（kAndElIACAndEl（l.）druCE）红树林Cu、Pb、zn、Mn元素的累积和生物循环。结果表明：该林地表层土壤（0~30CM深）Cu、Pb、zn、Mn元素的储量分别为6.86、4.23、25.64和134.67g/M2；植物体不同部位相应元素的含量范围分别为1.85~6.97、0.37~3.74、16.0~25.2和140~1405μg/g。群落Cu、Pb、zn、Mn元素的现存储量分别为87.98、40.34、335.34和8006.99Mg/M2；林地残留物中相应元素的储量分别为593.06、49.27、2450.79和43486.70μg/M2。群落Cu、Pb、zn、Mn元素的生物循环为：年吸收量分别为10.17、4.32、49.14和2268.16Mg/M2；年归还量分别为2.21、0.70、18.63和1574.98Mg/M2；年存留量分别为7.96、3.62、30.51和693.18Mg/M2；周转期分别为40、58、18和5年。吸收系数、利用系数和循环系数均为Mn＞zn＞Cu＞PbThe accumulation and biocycle of Cu,Pb,Zn and Mn elements were studied in Kandelia candel(L.)Druce mangrove community of Jiulong River Estuary of Fujian.The pool amounts of Cu,Pb,Zn and Mn elements in the Forest soil (0～30 cm in depth) were 6.86 ,4.23,25.64 and 134.67 g·m -2 ,respectively.The respective element contents ranged From in diFFerent parts of the plant, 1.85～6.97, 0.37～3.74, 16.0～25.2 and 140～1405 μg·g -1 of Cu,Pb,Zn and Mn.The pool amounts of elements in standing crop of the community were 87.98,40.34,335.34 and 8006.99 mg·m -2 For Cu,Pb,Zn and Mn respectively.The pool amounts of Cu,Pb,Zn and Mn elements in residues were: 593.06, 49.27, 2450.79 and 43486.70 μg·m -2 respectively.The biocycle of the elements in the community were described as Follows: Annual uptake of Cu was 10.17,Pb 4.32,Zn 49.14 and Mn 2268.16 mg·m -2 ;Annual return of Cu was 2.21,Pb 0.70,Zn 18.63 and Mn 1574.98 mg·m -2 ;Annual retention of Cu was 7.96,Pb 3.62,Zn 30.51 and Mn 693.18 mg·m -2 .The turnover periods of Cu,Pb,Zn and Mn were 40,58,18 and 5 year,respectively.The absorption,utilatizion and cycle coeFFicients were in the order of Mn>Zn>Cu>Pb.国家自然科学基

Character of Sand Beach Dynamic Despositional Environment in Xiamen University

通过在研究区海滩进行定位采样,结果表明,研究区海滩中潮位附近浅表层物质主要由粗砂至极粗砂的颗粒组成,各正态组分间的截点与频率分布曲线上低谷的位置并不一一对应,这些特征都与本区的强水动力有密切关系。The test at the beach of Xiamen University puttes forward,that the substances near the tested area's tidal stage are composed of coarse sand and extreme coarse sand,and each normal distribution group's cut-off point can't correspond to the frequency distribution line's all-time low position.The characteristicses have an close relation with the tested area's strong hydrodynnamical

Character of Sand Beach Dynamic Despositional Environment in Xiamen University

通过在研究区海滩进行定位采样,结果表明,研究区海滩中潮位附近浅表层物质主要由粗砂至极粗砂的颗粒组成,各正态组分间的截点与频率分布曲线上低谷的位置并不一一对应,这些特征都与本区的强水动力有密切关系。The test at the beach of Xiamen University puttes forward,that the substances near the tested area's tidal stage are composed of coarse sand and extreme coarse sand,and each normal distribution group's cut-off point can't correspond to the frequency distribution line's all-time low position.The characteristicses have an close relation with the tested area's strong hydrodynnamical

Imaging the homogeneous nucleation during the melting of superheated colloidal crystals

The nucleation process is crucial to many phase transitions, but its kinetics are difficult to predict and measure. We superheated and melted the interior of thermal-sensitive colloidal crystals and investigated by means of video microscopy the homogeneous melting at single-particle resolution. The observed nucleation precursor was local particle-exchange loops surrounded by particles with large displacement amplitudes rather than any defects. The critical size, incubation time, and shape and size evolutions of the nucleus were measured. They deviate from the classical nucleation theory under strong superheating, mainly because of the coalescence of nuclei. The superheat limit agrees with the measured Born and Lindemann instabilities

A Primary Study on Adsorption of Certain Heavy Metals on the Litter LeaF Detritus of Some Mangrove Species

研究四种红树植物落叶碎屑对水环境中重金属Cu、Pb、nI和Cd离子的吸附作用.结果表明：1）在单离子处理条件下，白骨壤叶对Pb、Cd的吸附能力较强；而秋茄叶对Cu、nI的吸附能力较强.2）在相同离子浓度下，拒盐植物（秋茄、红海榄）与泌盐植物（白骨壤、桐花树）落叶碎屑对不同重金属吸附能力具有一定差异：拒盐植物为Cd＞Pb＞Cu＞nI；而泌盐植物为Pb＞Cd＞Cu＞nI.3）随着水中重金属浓度增加（2~5Mg/l）落叶碎屑对重金属吸附量随之增大，表明红树落叶碎屑对重金属的吸附具有较大的潜在容量.4）多种重金属离子共存下，四种植物落叶对不同离子的吸附量均表现为Pb＞Cd＞Cu＞nIThe adsorption of Cu,Pb,Ni and Cd ions in water environment on the litter leaF detritus of Four mangrove species was studied.The results showed that:(1)Under the single ion condition,the adsorption abilities of Pb and Cd in Avicennia marina litter leaF detritus were higher,while that of Cu and Ni in Kandelia candel were higher;(2)At same ion concentrations,the saltexclusion species(K.candel and Rhizophora stylosa)and the saltexcretive species(A.marina and Aegiceras corniculatum)were diFFerence in adsorption ability of heavy metals i.e.,Cd>Pb>Cu>Ni For the Former,while Pb>Cd>Cu>Ni For the latter;(3)As rising of heavy metal ion concentration(From 2mg/L to 5 mg/L),the amount of adsorption was increased,which suggested that the litter leaF detritus of the mangroves was of high potential adsorption capacities;(4)In the coexistent ion system,the adsorption amount of each heavy metal ion was all in order of Pb>Cd>Cu>Ni For Four tested mangrove species.国家自然科学基

Structural signatures of dynamic heterogeneities in monolayers of colloidal ellipsoids

When a liquid is supercooled towards the glass transition,its dynamics drastically slows down,whereas its static structure remains relatively unchanged.Finding a structural signature of the dynamic slowing-down is a major challenge,yet it is often too subtle to be uncovered.Here we discovered the..

Transition from shear thinning to thickening in two-dimensional colloidal gels

The linear viscoelasticity of colloidal suspensions was extensively studied in the past several decades.However,the nonlinear response of colloidal systems to high shear rate was poorly understood.Here,we performed interfacial shearing on two dimensional colloidal gels composed of microscopic col..

胶体椭球系统玻璃态转变

玻璃材料的结构弛豫过程与其力学和热力学性质密切相关。过冷液体的黏度急剧增大,而静态结构却无明显变化。动力学减缓与静态结构的关系是多种玻璃态转变理论的核心问题。原子体系的结构往往难于捕捉,胶体系统中粒子的运动和结构可通过显微粒子追踪方法量化统计,被认为是研究物质相变的理想模型体系。相对于广泛研究的圆球系统,大多数分子和粒子并非球形,且粒子转动关联可揭示掩盖于圆球系统的现象和本质,而人们对非球形颗粒系统却了解甚少。我们利用显微观测和计算模拟研究二维胶体椭球系统,对过冷液体中粒子平动和转动的结构弛豫过程和动态非均匀时空尺度进行定量表征,对粒子局域结构的空间尺度演变进行定量表征。发现在系统平动和转动的玻璃态转变过程中,过冷液体慢速粒子团簇尺度、运动不均匀性的动态关联空间尺度,以及局域非晶结构和局域构型熵的静态关联空间尺度均呈现相同的幂指数发散行为。揭示了过冷液体的运动减缓起源于静态构型熵的降低和局域玻璃态结构尺度的增大。此外,我们研究了不同长径比的椭球体系,发现随着长径比增大,系统的平动和转动呈现同步和两步玻璃态转变行为,并具有截然不同的结构弛豫行为、动态不均匀性以及局域结构特性。此结果表明粒子形状的各向异性对系统玻璃态转变的结构和动力学行为具有重要影响