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Science China Chemistry 2013年第9期56卷 1315-1324页

作者： LIU Jie ZHANG Qiong DING HongJuan ZHANG Jun tan jingyun WANG ChuanKui WU JieYing LI ShengLi ZHOU HongPing YANG JiaXiang TIAN YuPeng Department of Chemistry Key Laboratory of Functional Inorganic Material Chemistry of Anhui ProvinceAnhui University Department of Physics Shandong Normal University State Key Laboratory of Coordination Chemistry Nanjing University

Two novel terpyridine-based chromophores with D-A (D = donor, A = acceptor) structural model containing modified triphenylamine moiety (L1 and L2 ) have been conveniently synthesized via formylation and reduction in satisfactory yields, and fully characterized. The single crystals of them were obtained and determined by X-ray diffraction analysis. The relationships between structure and photophysical properties of the two chromophores were investigated both experimentally and theoretically. The measured maximum TPA cross-sections per molecular weight (δmax /MW) of the chromophores are 0.63 GM/(g mol) (L1) and 0.72 GM/(g mol) (L2), respectively, in DMF as a high polar solvent. The results indicate that the value of δmax/MW could be well tuned by the intramolecular charge transfer (ICT), which could be realized by introducing additional elecron-donor/acceptor groups.

关键词： terpyridine derivatives photophysical properties structure-property relationships TD-DFT calculation two-photon-excited fluorescence

Error estimates of a finite element method for stochastic time-fractional evolution equations with fractional Brownian motion

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International Journal of Modeling, Simulation, and Scientific Computing 2022年第1期13卷 192-213页

作者： jingyun Lv Key Laboratory of Systems and Control Institute of Systems Science Academy of Mathematics and Systems Science Chinese Academy of Sciences Beijing 100190 P.R.China School of Mathematical Sciences University of Chinese Academy of Sciences Beijing 100049 P.R.China

The aim of this paper is to consider the convergence of the numerical methods for stochastic time-fractional evolution equations driven by fractional Brownian *** spatial and temporal regularity of the mild solution is *** numerical scheme approximates the problem in space by the Galerkin finite element method and in time by the backward Euler convolution quadrature formula,and the noise by the L *** strong convergence error estimates for both semi-discrete and fully discrete schemes are established.A numerical example is presented to verify our theoretical analysis.

关键词： Stochastic time-fractional evolution equations finite element method error estimates fractional Brownian motion

净制对乌梅质量的影响及乌梅肉质量标准的研究

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世界中医药 2024年第1期19卷 1-6,13页

作者：杨琳琳辛洁萍张姝妍王鑫谭景匀王璇程水清文佳徐新房李向日北京中医药大学中药炮制研究中心/中药品质评价重点实验室北京102488

目的:研究净制对乌梅质量的影响,完善乌梅肉质量标准。方法:首先采用蒸与润2种方法分别净制3批乌梅肉样品,比较其产率、浸出物以及枸橼酸含量差异,确定净制方法;根据确定的净制方法,对12批乌梅药材进行净制,比较乌梅肉和核中浸出物及枸... 详细信息

目的:研究净制对乌梅质量的影响,完善乌梅肉质量标准。方法:首先采用蒸与润2种方法分别净制3批乌梅肉样品,比较其产率、浸出物以及枸橼酸含量差异,确定净制方法;根据确定的净制方法,对12批乌梅药材进行净制,比较乌梅肉和核中浸出物及枸橼酸含量差异,探讨净制对乌梅质量的影响。对21批乌梅肉饮片的外观性状、显微、薄层鉴别、水分、水溶性浸出物和枸橼酸含量分别按照药典要求进行测定,拟定乌梅肉质量标准限度。结果:蒸法与润法净制乌梅质量(产率、水分、枸橼酸及浸出物)无显著性差异,但蒸法所用时间为30 min,远短于润法润制过夜。乌梅肉的浸出物及枸橼酸的含量72.5%、33.1%远高于乌梅核17.9%、8.0%,二者存在极显著差异。乌梅肉的平均水分为(11.0±1.4)%;浸出物为(72.0±3.4)%;枸橼酸含量为(33.8±4.5)%。结论:乌梅净制可以去除非药用部位,提高枸橼酸及浸出物含量,具有科学道理,蒸法和润法2种净制方法均可行,蒸法更易操作。

关键词：乌梅乌梅肉净制浸出物枸橼酸质量控制质量标准

Application of high OLR-fed aerobic granules for the treatment of low-strength wastewater: Performance, granule morphology and microbial community

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Journal of Environmental Sciences 2013年第8期25卷 1549-1556页

作者： jingyun Ma Xiangchun Quan Huai Li Key Laboratory of Water and Sediment Sciences of Ministry of Education/State Key Laboratory of Water Environment Simulation School of Environment Beijing Normal University

Aerobic granules, pre-cultivated at the organic loading rate （OLR） of 3.0 kg COD/（m3 ·day）, were used to treat low-strength wastewater in two sequencing batch reactors at low OLRs of 1.2 and 0.6 kg COD/（m3 ·day）, respectively. Reactor performance, evolution of granule morphology, structure and microbial community at low OLRs under long-term operation （130 days） were investigated. Results showed that low OLRs did not cause significant damage to granule structure as a dominant granule morphology with size over 540 μm was maintained throughout the operation. Aerobic granules at sizes of about 750 μm were finally obtained at the low OLRs. The granule reactors operated at low OLRs demonstrated effective COD and ammonia removals （above 90%）, smaller granule sizes and less biomass. The contents of extracellular polymeric substances in the granules were decreased while the ratios of exopolysaccharide/exoprotein were increased （above 1.0）. The granules cultivated at the low OLRs showed a smoother surface and more compact structure than the seeded granules. A significant shift in microbial community was observed but the microbial diversity remained relatively stable. Confocal Laser Scanning Microscopy observation showed that the live cells were spread throughout the whole granule, while the dead cells were mainly concentrated in the outer layer of the granule, and the proteins, polysaccharides and lipids were mainly located in the central regime of the granule. In conclusion, granules cultivated at high OLRs show potential for treating low-strength organic wastewater steadily under long-term operation.

关键词： aerobic granule biodegradation low-strength wastewater organic loading rate microbial community

Toward accurate accounting of ecosystem carbon stock in China's forests

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Science Bulletin 2016年第24期61卷 1888-1889页

作者： Huifeng Hu Yuanhe Yang jingyun Fang State Key Laboratory of Vegetation and Environmental Change Institute of Botany Chinese Academy of SciencesBeijing 100093 China Department of Ecology College of Urban and Environmental Science Key Laboratory for Earth Surface Processes of the Ministry of Education Peking University Beijing 100871 China

Forests play a dominant role in the global terrestrial carbon （C） cycle due to their huge area and large capacity for C stock and productivity [1-4]. They occupy around 30% of the global land surface with about 4.2 ×109 ha, store over 80% of vegetation C and around 60% of soil organic C in terrestrial biosphere, and contribute almost the entire terrestrial C sinks during the last 20 years [1, 2]. China provides a unique area to study the forest C cycle. Firstly, it ranks the fifth in forest area in the world, and encompasses various forest biomes, ranging from boreal forests in the north to the subtropical/tropical evergreen broadleaf forests in the south [5]. Moreover, with the implementation of national afforestation and reforestation programs since the late 1970s, China now has the largest plantation area [6].

关键词：森林生态系统碳储量中国热带常绿阔叶林核算森林面积造林项目陆地生物圈

Spinodal dynamics of metastable glass transition domains in amorphous polymer towards thermomechanically tailorable shape memory effect

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Science China(Technological Sciences) 2023年第8期66卷 2432-2440页

作者： LIU jingyun LU HaiBao FU Yong-Qing Science and Technology on Advanced Composites in Special Environments Laboratory Harbin Institute of TechnologyHarbin 150080China Faculty of Engineering and Environment Northumbria UniversityNewcastle upon TyneNE18STUK

Glass transition plays a critical role to determine the dynamic behaviors of amorphous shape memory polymers(SMPs).However,the fundamental relationships between shape memory effect(SME)and dynamic glass transition have not been well understood,even though this topic has been studied for *** this study,we apply a mean-square displacement function of Adam-Gibbs(AG)domain size model to explore metastable glass transition between normal glass state and rubbery state of amorphous SMPs,based on both mode-coupling theory and mean-field model.A statistic viscosity equation is formulated to study the dynamic glass transition of metastable AG domains in an amorphous SMP.A dynamically spinodal model is also developed to connect dynamic glass transitions to thermomechanical processes,based on statistic viscosity equation and phase transition ***,using the spinodal models,multiple shape memory behaviors have been predicted for amorphous SMPs with dual-,triple-and quadruple-SMEs,resulted from their different routes of themomechanical ***,the proposed models are verified using the experimental data reported in literature.

关键词： shape memory polymer glass transition dynamics metastable

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Recent advances of pharmaceutical crystallization theories

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Chinese Journal of Chemical Engineering 2020年第4期28卷 935-948页

作者： jingyun Weng Yiping Huang Dule Hao Yuanhui Ji Jiangsu Province Hi-Tech Key Laboratory for Biomedical Research School of Chemistry and Chemical EngineeringSoutheast UniversityNanjing 211189China

As a technology of separation and purification,crystallization plays a vital role in diverse industries such as inorganic salt,pharmaceutical,and food industries,which has a huge impact on purity,crystal polymorph,crystal morphology,and particle size distribution of final *** the past few decades,with the rapid advancement of experimental approaches and molecular simulation methods,considerable advances in the interpretation of crystallization mechanisms have been obtained,promoting the investigation and understanding of crystallization theories *** this review,the advances of pharmaceutical crystallization theories in recent years from the perspectives of nucleation and crystal growth are summarized and *** thermodynamic models that are helpful in the study of the crystallization mechanisms will be *** this section,the perturbed-chain statistical associating fluid theory(PC-SAFT)and a chemical-potential-gradient model will be introduced,which have been successfully applied in pharmaceutical solubility prediction,the research of dissolution mechanism as well as dissolution kinetics *** two models are expected to be applied to the study of pharmaceutical crystallization process and ***,molecular simulation based on the interaction between particles can provide structural information,thermodynamics,and dynamics properties of complex systems at the molecular level,like intermolecular interaction and surface adsorption *** and some shortcomings of molecular simulation,especially molecular dynamics simulation,in the field of pharmaceutical crystallization will be expounded.

关键词： Nucleation Crystal growth Thermodynamics Molecular simulation

Satellite-based Studies on Large-Scale Vegetation Changes in China

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Journal of Integrative Plant Biology 2012年第10期54卷 713-728页

作者： Xia Zhao Daojing Zhou jingyun Fang State Key Laboratory of Vegetation and Environmental Change Institute of Botany the Chinese Academy of SciencesBeijing 100093 China Department of Ecology College of Environmental Sciences and Key Laboratory of Earth Surface Processes of the Ministry of EducationPeking University Beijing 100871 China

Remotely-sensed vegetation indices, which indicate the density and photosynthetic capacity of vegetation, have been widely used to monitor vegetation dynamics over broad areas. In this paper, we reviewed satellite-based studies on vegetation cover changes, biomass and productivity variations, phenological dynamics, desertification, and grassland degradation in China that occurred over the past 2-3 decades. Our review shows that the satellite-derived index （Normalized Difference Vegetation Index, NDVI） during growing season and the vegetation net primary productivity in major terrestrial ecosystems （for example forests, grasslands, shrubs, and croplands） have significantly increased, while the number of fresh lakes and vegetation coverage in urban regions have experienced a substantial decline. The start of the growing season continually advanced in China＇s temperate regions until the 1990s, with a large spatial heterogeneity. We also found that the coverage of sparsely-vegetated areas declined, and the NDVI per unit in vegetated areas increased in arid and semi-arid regions because of increased vegetation activity in grassland and oasis areas. However, these results depend strongly not only on the periods chosen for investigation, but also on factors such as data sources, changes in detection methods, and geospatial heterogeneity. Therefore, we should be cautious when applying remote sensing techniques to monitor vegetation structures, functions, and changes.

关键词： Normalized Difference Vegetation Index (NDVI) phenology remote sensing vegetation coverage vegetation degradation vegetation productivity

Anode reaction mechanisms of Na|NaCl-CaCl2|Zn liquid metal battery

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Journal of Energy Chemistry 2022年第9期31卷 81-87,I0003页

作者： Fang Zhang jingyun Jin Junli xu Zhongning Shi School of Metllurgy Northeastem UniversityShenyang110819LiaoningChina Colege of Sciences Northeastem UniversityShenyang100819LiaoningChina State Key Laboratory of Roling and Automation Northeastern UniversiyShenyang 110819LiaoningChina

Na|NaCl-CaCl_(2)|Zn liquid metal battery is regarded as a promising energy storage system for power *** intensive attempts to present a real mechanism of metal electrodes reaction, those for Na||Zn LMBs are not clear yet. Herein, the anode reactions for the multiple discharge potential plateaus were deduced by means of FactSage thermochemical software, which were subsequently validated by X-ray diffraction analysis and the modeling of phase transformation in the cooling process. A pre-treatment process was proposed for the analysis of anode product composition using the atomic absorption spectrometry method, and the anode states at working temperature(560 ℃) were obtained by the Na-CaZn ternary phase for the first time. The results indicate the discharge of Na and Ca led to the formation of Ca-Zn intermetallic compounds, whilst the extraction of Ca in Ca-Zn intermetallic compounds was responsible for the multiple discharge plateaus. Moreover, it was found that the charging product was in electrochemical double liquid metal layers, which are composed of Na and Ca with dissolved Zn respectively.

关键词： Liquid metal battery Thermodynamic calculation Discharge plateaus Reaction mechanisms Ca-Zn intermetallic compounds

Dissolution-precipitation growth of uniform and clean two dimensional transition metal dichalcogenides

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National Science Review 2021年第3期8卷 108-116页

作者： Zhengyang Cai Yongjue Lai Shilong Zhao Rongjie Zhang Junyang tan Simin Feng jingyun Zou Lei tang Junhao Lin Bilu Liu Hui-Ming Cheng Shenzhen Geim Graphene Center Tsinghua-Berkeley Shenzhen Institute and Tsinghua Shenzhen International Graduate SchoolTsinghua University Shenyang National Laboratory for Materials Sciences Institute of Metal ResearchChinese Academy of Sciences Department of Physics Southern University of Science and Technology

Two dimensional transition metal dichalcogenides(TMDCs) have attracted much interest and shown promise in many ***,it is challenging to obtain uniform TMDCs with clean surfaces,because of the difficulties in controlling the way the reactants are supplied to the reaction in the current chemical vapor deposition growth ***,we report a new growth approach called’dissolution-precipitation’(DP) growth,where the metal sources are sealed inside glass substrates to control their feeding to the ***,the diffusion of metal source inside glass to its surface provides a uniform metal source on the glass surface,and restricts the TMDC growth to only a surface reaction while eliminating unwanted gas-phase *** feature gives rise to highly uniform monolayer TMDCs with a clean surface on centimeter-scale *** DP growth works well for a large variety of TMDCs and their alloys,providing a solid foundation for the controlled growth of clean TMDCs by the fine control of the metal source.

关键词： dissolution-precipitation growth two dimensional materials transition metal dichalcogenides uniform clean