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合成金刚石的晶体形态对天然金刚石的启示

地质学报 2024年第6期98卷 1743-1756页

作者：鲁智云杨经绥连东洋吴魏伟杨彧曹楚奇蔡鹏捷浙江大学地球科学学院浙江杭州310058 南京大学地球科学与工程学院内生金属矿床成矿机制研究国家重点实验室江苏南京210023 中国地质科学院地质研究所北京100037

作为深部地球研究的“信使”,不同类型天然金刚石的形成温度、压力及环境介质条件一直是地球科学中的重要内容。天然金刚石原石呈现出多种多样的晶型和表面形貌特征是其结晶过程、介质环境和运移过程的最直接记录。伴随着金刚石高温高... 详细信息

作为深部地球研究的“信使”,不同类型天然金刚石的形成温度、压力及环境介质条件一直是地球科学中的重要内容。天然金刚石原石呈现出多种多样的晶型和表面形貌特征是其结晶过程、介质环境和运移过程的最直接记录。伴随着金刚石高温高压合成技术的发展以及合成金刚石的规模化工业生产应用,前人对合成金刚石的晶型及表面形貌特征进行了大量的描述并详细探讨了温度、压力及组分差异对晶体形态的影响。本文对不同条件下的合成金刚石与不同类型天然金刚石的晶型特征、表面形貌特征进行了详细的对比分析,旨在将高温高压实验中明确的生长条件及晶体生长规律应用于天然金刚石形成条件的研究中,并进一步为金刚石晶体形态反映出的地质环境特征、地幔流体/熔体组成和动力学条件的研究提供约束。

关键词：金刚石高温高压实验晶型表面形貌温度压力

Super-resolution imaging and real-time tracking lysosome in living cells by a fluorescent probe

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Science China Chemistry 2018年第4期61卷 483-489页

作者： Wencheng Zhu Xujun Zheng Yan Huang zhiyun lu Hua Ai National Engineering Research Center for Biomaterials Sichuan UniversityChengdu 610064China Key Laboratory of Green Chemistry and Technology Ministry of Education College of Chemistry Sichuan UniversityChengdu 610064China Shanghai Institute of Biochemistry and Cell Biology Chinese Academy of SciencesShanghai 200031China

Lysosomes function as important organelles within cells and their movement associates with diverse biological events, hence the real-time tracking of lysosomal movement is of great significance. However, since most ly so some fluorescent probes suffer from relatively unsatisfactory photo stability,tracking lysosomal movement in real-time remains challenging. Here,we report that a naphthalimide-based fluorescent compound,namely NIMS,is a quite promising probe for ly so some imaging. The visualizing mechanism lies in the selective accumulation of NIMS in lysosomes via a protonation reaction, followed by the fluorescence enhancement due to the interactions of NIMS with proteins. Owing to its high selectivity and good photo stability, NIMS was successfully applied to capture super-resolution fluorescence images of lysosomes. More importantly, real-time tracking of ly so some movement in a single living cell by NIMS was realized with a confocal laser scanning microscope. Surprisingly,even in normal culture conditions, around 2/3 of the captured lysosomes were observed to move within 5 min, indicative of the highly dynamic features of lysosomes. Thus, this probe may facilitate the understanding of the ly so some dynamics in physiologicalor pathological conditions.

关键词： lysosome imaging protonation photostability naphthalimide

哀牢山中山湿性常绿阔叶林树种幼苗群落对季节和地形的响应

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广西植物 2024年第8期44卷 1592-1606,I0001-I0003页

作者：沈金凤宋晓阳温韩东鲁志云杨洁曹敏中国科学院西双版纳热带植物园热带森林生态学重点实验室云南勐腊666303 中国科学院大学北京100049 哀牢山森林生态系统云南省野外科学观测研究站云南景东676200

幼苗期是植物发育过程中最重要的阶段,也是森林自然更新的关键时期。为探究哀牢山中山湿性常绿阔叶林树种幼苗组成、季节动态及其空间分布,该研究以20 hm 2监测样地为平台,通过对样地内450个1 m×1 m样方连续4年(2019—2022年)的调查,... 详细信息

幼苗期是植物发育过程中最重要的阶段,也是森林自然更新的关键时期。为探究哀牢山中山湿性常绿阔叶林树种幼苗组成、季节动态及其空间分布,该研究以20 hm 2监测样地为平台,通过对样地内450个1 m×1 m样方连续4年(2019—2022年)的调查,分析树种幼苗的组成、新增和死亡季节动态、空间分布等。结果表明:(1)累计调查幼苗58种,2928株,分属于26科42属。其中,新增幼苗817株,新增物种47种;死亡幼苗1181株,死亡物种50种。(2)幼苗重要值在不同树种和年际间表现出较大的差异,多花山矾(Symplocos ramosissima)和黄心树(Machilus bombycina)的幼苗始终是优势种,重要值始终在前2位,而先锋种水红木(Viburnum cylindricum)重要值则持续下降。(3)未监测到幼苗物种丰富度、样方平均幼苗物种丰富度和物种多样性(Shannon-Wiener指数和Simpson指数)、幼苗数量、新增幼苗数量、幼苗新增率、死亡幼苗数量和幼苗死亡率的季节性差异。(4)多数幼苗物种的空间分布范围较窄,仅有少数树种幼苗在整个样地广泛分布。平地地形中的样方幼苗物种丰富度、幼苗密度和物种多样性(Shannon-Wiener指数和Simpson指数)显著高于山脊和沟谷地形。综上认为,哀牢山中山湿性常绿阔叶林中季节对树种幼苗组成、新增和死亡的影响不大,地形决定树种幼苗的分布和多样性。该研究结果揭示了树种幼苗新增和死亡的动态变化,为生物多样性保护和森林经营管理提供了理论依据。

关键词：哀牢山森林更新物种组成季节动态幼苗分布

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A Novel Ratiometric Oxygen Sensor Based On a Sextuple Hydrogen-Bonding Self-Assembly Molecular Heterodimer

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Chinese Journal of Chemistry 2016年第9期34卷 873-877页

作者： Hui Zeng Cheng Zhang Yan Huang zhiyun lu Key Laboratory of Green Chemistry and Technology (Ministry of Education) College of Chemistry Sichuan University Chengdu Sichuan 610064 China

A novel sextuple hydrogen-bonding （HB） self-assembly molecular heterodimer bearing an iridium complex as the indicator dye and two carbazoles as the reference dye, namely 6HB-Irbt-Cz, was synthesized, and its molecular structure was confirmed by ^1H NMR, ^13CNMR, TOF-MS and 2D NMR. Because of the inefficient energy transfer process between the carbazole and iridium complex units, 6HB-Irbt-Cz exhibits distinct fluorescence/ phosphorescence dual emission in neat film state. More importantly, the neat film sample of 6HB-Irbt-Cz could display linear ratiometric optical response toward oxygen in the full oxygen concentration range from 0 to 100 vol%, together with good stability, reversibility and rapid response-recovery times. Note that this represents the first discovery of neat-film-based oxygen sensor capable of showing strictly linear ratiometric Stem-Volmer behavior in the oxygen concentration of 0- 100 vol%.

关键词： hydrogen-bonding self-assembly molecular heterodimer oxygen sensor ratiometric response 0- 100 vol% oxygen concentration range linear Stern-Volmer behavior

Translocation and distribution of mercury in biomasses from subtropical forest ecosystems:evidence from stable mercury isotopes

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Acta Geochimica 2021年第1期40卷 42-50页

作者： Yi Liu Che-Jen Lin Wei Yuan zhiyun lu Xinbin Feng State Key Laboratory of Environmental Geochemistry Institute of Geochemistry.Chinese Academy of SciencesGuiyangChina University of Chinese Academy of Sciences BeijingChina Center for Advances in Water and Air Quality Lamar UniversityBeaumontTXUSA College of Environment and Energy South China University of TechnologyGuangzhouChina National Forest Ecosystem Research Station AilaoshanYunnanChina

To understand its source,distribution,storage,and translocation in the subtropical forest ecosystems,mercury(Hg)concentrations and stable isotopes in forest biomass tissues(foliage,branch,bark,and trunk)were investigated at Ailao Mountain National Nature Reserve,Southwest *** total Hg(THg)concentrations in the samples show the following trend:mature foliage(57±19 ng g-1)>bark(11±4.0 ng g-1)>branch(5.4±2.5 ng g-1)>trunk(1.6±0.7 ng g-1).Using the measured THg concentrations and the quantity of respective biomasses,the Hg pools in the forest are:wood(60±26μg m-2)>bark(51±18μg m-2)>foliage(41±11μg m-2)>branch(26±8.3μg m-2).The tree biomasses displayed negativeδ202Hg(-1.83‰to-3.84‰)andΔ199Hg(-0.18‰to-0.62‰).The observedΔ200Hg(-0.08‰to 0.04‰)is not significantly from zero.AΔ199Hg/Δ201Hg ratio of 1.05 was found in tree biomasses,suggesting that mercury has undergone Hg(Ⅱ)photoreduction processes.A Hg-isotope based binary mixing model suggests that Hg in the tree biomasses mainly originated from foliage uptake of atmospheric Hg0,constituting 67%,80%,and 77%of Hg in wood,branch,and bark,*** study sheds new light on the transportation and sources of Hg in the subtropical forest ecosystems.

关键词： Hg Subtropical forest ecosystem Hg stable isotope Hg-isotope based binary mixing model

A Red-Emissive Sextuple Hydrogen-Bonding Self-Assembly Molecular Duplex Bearing Perylene Diimide Fluorophores for Warm-White Organic Light-Emitting Diode Application

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Chinese Journal of Chemistry 2016年第4期34卷 387-396页

作者： Hui Zeng Qingyu Huang Jingjing Liu Yan Huang Jie Zhou Suling Zhao zhiyun lu Key Laboratory of Green Chemistry and Technology of Ministry of Education College of Chemistry Sichuan University Chengdu Sichuan 610064 China Key Laboratory of luminescence and Optical Information (Min&try of Education) Institute of Optoelectronics Technology Beijing Jiaotong University Beijing 100044 China

A novel sextuple hydrogen-bonding （HB） self-assembly molecular duplex bearing red-emitting perylene diimide （PDI） fluorophores, namely PDIHB, was synthesized, and its molecular structure was confirmed by IH NMR, 13C NMR, TOF-MS and 2D NMR. Compared with the small molecular reference compound PDI, PDIItB shows one time enhanced fluorescence efficiency in solid state （4.1% vs. 2.1%）. More importantly, the presence of bulky HB oli- goamide strands in PDIHB could trigger effective spatial separation between guest and host fluorophores in thin solid film state, hence inefficient energy transfer occurs between the blue-emitting host 2TPhNII/B and red guest PDIHB in the 2 wt% guest/host blending film. As a result, a solution-processed organic light-emitting diode （OLED） with quite simple device structure of ITO/PEDOT：PSS （40 nm）/PVK （40 nm）/PDIHB （2 wt%）： 2TPhNII-IB （50 nm）/LiF （0.8 nm）/A1 （100 nm） could emit bias-independent warm-white electroluminescence with stable Commission Intemationale de L＇Eclairage coordinates of （0.42, 0.33）, and the maximum brightness and current efficiency of this device are 260 cdom-2 and 0.49 cd·A-1, respectively. All these results indicated that HB self-assembly supramolecular fluorophores could act as prospective materials for white OLED application.

关键词： hydrogen-bonding self-assembly duplex perylene diimide inefficient energy transfer warm-whiteorganic light-emitting diode

云南哀牢山退化常绿阔叶林乔木多样性和生物量的恢复

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热带亚热带植物学报 2024年第4期32卷 500-510页

作者：李雪楠杞金华徐志雄鲁志云范泽鑫栗忠飞张树斌西南林业大学生态与环境学院昆明650224 中国科学院热带森林生态学重点实验室云南勐腊666303 云南哀牢山森林生态系统国家野外科学观测研究站云南景东676200

为了探究退化森林的树种组成变化和生物量储量的恢复规律,该研究选取云南哀牢山不同演替阶段的常绿阔叶林为对象,比较了不同演替阶段森林群落结构、树种多样性和生物量变化。结果表明,从演替早期到演替末期,乔木的科数先减少后增多,属... 详细信息

为了探究退化森林的树种组成变化和生物量储量的恢复规律,该研究选取云南哀牢山不同演替阶段的常绿阔叶林为对象,比较了不同演替阶段森林群落结构、树种多样性和生物量变化。结果表明,从演替早期到演替末期,乔木的科数先减少后增多,属数和种数则逐渐增加;Margalef丰富度指数、Simpson优势度指数、Shannon-Wiener多样性指数和Pielou均匀度指数随演替进程均呈增加的趋势;乔木生物量储量随演替进程逐渐升高,演替早期和演替中期的生物量分别为演替末期生物量的9.87%和65.98%;群落水平的树种多样性指数与总生物量呈显著正相关关系(P<0.05)。树木的生长和树种多样性的提高是影响群落乔木生物量储量递增的因素,且哀牢山处于湿冷的气候条件,退化森林植被的恢复相对比较缓慢。

关键词：哀牢山森林演替群落结构植物多样性生物量

Tetraphenylethylene-conjugated polycation covered iron oxide nanoparticles for magnetic resonance/optical dual-mode imaging

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Regenerative Biomaterials 2021年第3期8卷 124-132页

作者： Li Yang Shengxiang Fu Li Liu Zhongyuan Cai Chunchao Xia Bin Song Qiyong Gong zhiyun lu Hua Ai National Engineering Research Center for Biomaterials Sichuan UniversityChengdu 610065China Department of Radiology West China HospitalSichuan UniversityChengdu 610041China Huaxi MR Research Center(HMRRC) Department of RadiologyWest China Hospital of Sichuan UniversityChengduChina Psychoradiology Research Unit of Chinese Academy of Medical Sciences Sichuan UniversityChengduChina Key Laboratory of Green Chemistry and Technology(Ministry of Education) College of ChemistrySichuan UniversityChengdu 610065China

Magnetic resonance(MR)/optical dual-mode imaging with high sensitivity and high tissue resolution have attracted many attentions in biomedical *** avert aggregation-caused quenching of conventional fluorescence chromophores,an aggregation-induced emission molecule tetraphenylethylene(TPE)-conjugated amphiphilic polyethylenimine(PEI)covered superparamagnetic iron oxide(Alkyl-PEI-LAC-TPE/SPIO nanocomposites)was prepared as an MR/optical dual-mode ***-PEI-LAC-TPE/SPIO nanocomposites exhibited good fluorescence property and presented higher T2 relaxivity(352 Fe mM1s1)than a commercial contrast agent Feridex(120 Fe mM1s1)at 1.5 *** alkylation degree of Alkyl-PEI-LAC-TPE effects the restriction of intramolecular rotation process of *** alkane chain grafting ratio aggravated the stack of TPE,increasing the fluorescence lifetime of Alkyl-PEI-LAC-TPE/SPIO ***-PEI-LAC-TPE/SPIO nanocomposites can effectively labelled HeLa cells and resulted in high fluorescence intensity and excellent MR imaging *** an MR/optical imaging probe,Alkyl-PEI-LAC-TPE/SPIO nanocomposites may be used in biomedical imaging for certain applications.

关键词： magnetic resonance imaging optical imaging superparamagnetic iron oxide aggregation-induced emission dual-mode imaging

The Influence of Temperature on the Afterglow Feature of SrAl_2O_4∶Eu,Dy Phosphors

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Journal of Wuhan University of Technology(Materials Science) 2006年第3期21卷 120-122页

作者：王兵 Materials School Southwest University of Science and TechnologyMianyang 621010China

Using a self-designed temperature testing box in which Xenon-lamp irradiation can be applied, the afterglow feature of SrAl2O4： Eu, Dy as a function of temperature has been researched. Two sorts of SrAl2O4 ： Eu, Dy phosphors, namely highest quality commercial one and the self-synthesized one by solid-state reaction process were employed. Results reveal a common phenomenon behaving as phosphorescent sudden extinguishments at a certain low temperature although their threshold temperature value （ about 223 K） has a slight difference . The general charueteristic for the influence of temperature on the afterglow feature presents, compared to the luminescent decay at room temperature （RT）, a bigger and faster decrease of phosphorescent brightness with the reduction of temperature, while decay curves still maitain the same pattern composed of a quick decline part and a platform falling part during which the phosphorescent brightness at 273 K is only aboat 1/2 as big as that at RT, and at 253 K the figure has changed to about 1/3. Finally , the reason of previous observed results has been analyzed briefly in theory.

关键词： afterglow SrAl2O4:Eu,Dy low temperature