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Heterogeneity Analysis of Cucumber Canopy in the Solar Greenhouse

Journal of Integrative Agriculture 2014年第12期13卷 2645-2655页

作者： QIAN Ting-ting LU Sheng-lian ZHAO Chun-jiang GUO Xin-yu WEN Wei-liang DU jian-jun Shanghai Jiao Tong University Beijing research center for Information Technology in Agriculture

Detailed analysis of canopy structural heterogeneity is an essential step in conducting parameters for a canopy structural model. This paper aims to analyze the structural heterogeneity of a cucumber （Cucumis sativus L.） canopy by means of analyzing leaf distribution in a greenhouse environment with natural sunlight and also to assess the effect of structural canopy heterogeneity on light interception and photosynthesis. Two experiments and four measurements were carried out in autumn 2011 and spring 2012. A static virtual three-dimensional （3D） canopy structure was reconstructed using a 3D digitizing method. The diurnal variation of photosynthesis rate was measured using CIRAS-2 photosynthesis system. The results showed that, leaf azimuth as tested with the Rayleigh-test was homogeneous at vine tip over stage but turned heterogeneous at fruit harvest stage. After eliminating the inlfuence of the environment on the azimuth using the von Mises-Fisher method, the angle between two successive leaves was 144°;at the same time, a rule for the azimuth distribution in the canopy was established, stating that the azimuth distribution in cucumber followed a law which was positive spin and anti-spin. Leaf elevation angle of south-oriented leaves was on average 13.8° higher than that of north-oriented leaves. The horizontal distribution of light interception and photosynthesis differed signiifcantly between differently oriented leaves. East-and west-oriented leaves exhibited the highest photosynthetic rate. In conclusion, detailed analysis of canopy structural heterogeneity in this study indicated that leaf azimuth and elevation angle were heterogeneous in cucumber canopy and they should be explicitly described as they have a great impact both on light distribution and photosynthesis.

关键词： heterogeneity inclination leaf azimuth light interception photosynthesis

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Addressing the environmental risk of persistent organic pollutants in China

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Frontiers of Environmental Science & Engineering 2012年第1期6卷 2-16页

作者： Bin WANG Jun HUANG Shubo DENG Xiaoling YANG Gang YU POPs research center School of EnvironmentTsinghua UniversityBeijing 10084China

The Stockholm Convention on persistent organic pollutants （POPs） was adopted in 2001. This year is the 10th anniversary of the adoption of the Convention. Until now, 22 chemicals or chemical categories have been listed as POPs in the Stockholm Convention. The POPs research center was established in Tsinghua University in the same year when the Convention was adopted. In the last ten years, much work has been done by Chinese researchers to understand the environ- mental risk of POPs in China. This article aims to review the recent research progress of our POPs research center and some other Chinese researchers＇ studies in addressing the environmental risk of POPs, including the priority screening and inventory study of POPs, monitoring and modeling of POPs pollution and exposure, and environ- mental risk assessment and modeling of POPs. Although great advances in addressing the environmental risk of POPs have been made in recent years, we are still facing quite a few problems, such as data scarcity and uncertainty in environmental risk assessment of POPs. The study on the effect of POPs mixtures is in its infancy and currently POPs are usually assessed from legal perspective by risk assessment of single chemicals. These problems should be well addressed by further efforts. Further studies should also be taken in future to study environment risk of POPs by considering aspects of coupled dynamics between climate processes and POPs. Such sound scientific, riskbased information can support decision-making aiming to effectively minimize the risk level of POPs.

关键词： persistent organic pollutant (POPs) environ- mental risk assessment inventory environmental monitoring fugacity model emerging POPs

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A shape-reconfigurable,light and magnetic dual-responsive shape-memory micropillar array chip for droplet manipulation

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Chinese Chemical Letters 2024年第1期35卷 456-460页

作者： Wen-Qi Ye Wen-Xin Fu Xiao-Peng Liu Chun-Guang Yang Zhang-Run Xu research center for Analytical Sciences Northeastern UniversityShenyang 110819China

Droplet manipulation on an open surface has great potential in chemical analysis and biomedicine ***,most of the reported platforms designed for the manipulation of water droplets cannot thoroughly solve the problem of droplet ***,we report a shape-reconfigurable micropillar array chip for the manipulation of water droplets,oil droplets and water-in-oil ***-in-oil droplets provide an enclosed space for water droplets,preventing the evaporation in an open *** coated on the surface of the chip effectively reduces the droplet movement *** micropillar array chip has light and magnetic dual-response due to the Fe3O4 nanoparticles and the reduced iron powder mixed in the shape-memory *** micropillars irradiated by a near-infrared laser bend under the magnetic force,while the unirradiated micropillars still keep their original *** the absence of a magnetic field,when the micropillars in a temporary shape are irradiated by the near-infrared laser to the transition temperature,the micropillars return to their initial *** this process,the surface morphology gradient caused by the deformation of the micropillars and the surface tension gradient caused by the temperature change jointly produce the driving force of droplet movement.

关键词： Microfluidics Droplet manipulation Micropillar array Shape memory polymer Magnetic response Light response

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Recent advances in mass spectrometry analysis of low molecular weight heparins

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Chinese Chemical Letters 2018年第1期29卷 11-18页

作者： Zhangjie Wang Lianli Chi National Clycoengineering research center Shandong University Ji'nan 250100 China

Carbohydrates are important biomolecules and promising novel drug candidates, but their structural complexity and heterogeneity hinder their study and application. Low molecular weight heparins （LMWHs） are widely used as anticoagulants in the clinic and are considered the most successful carbohydrate-based drugs. They consist of both natural structures inherited from parent heparin and modified structures derived from depolymerization reactions. Sophisticated analytical methods are in great demand to elucidate the fine structure of LMWHs. This review summarizes recent progress in mass spectrometry （MS） that facilitates the in-depth structural characterization of LMWHs. The strategies can be sorted into top-down approaches and bottom-up approaches. In top-down approaches, the intact ohgosaccharides are analyzed directly by hyphenated MS techniques to reveal their distribution and composition. Bottom-up approaches provide complementary structural information by analyzing partially enzymatica]ly digested fragments or exhaustively degraded disaccharide building blocks of LMWHs. Advances in the MS/MS sequencing of short oligosaccharides and bioinformatics tools are also reviewed. Multidimensional analysis by MS offers a rigorous inspection of LMWHs, which is indispensable for ensuring drug quality and expanding their applications.

关键词： LMWHsMSStructural characterizationChain mappingSequence

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Advances of CNT-based systems in thermal management

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Nano research 2021年第8期14卷 2471-2490页

作者： Wei Yu Changhong Liu Shoushan Fan Tsinghua-Foxconn Nanotechnology research center and Department of Physics Tsinghua UniversityBeijing 100084China

Effective thermal management has become extremely urgent for electronics due to the massive heat originated from the ever-rising power *** the merits of high thermal conductivity,good chemical stability and desirable mechanical properties,carbon nanotubes(CNTs)are considered to have great potential to be widely used in heat dissipation *** article describes the progress on thermal conductivity of CNT-reinforced composites,aligned CNT materials(aligned CNT arrays,films/buckypapers and fibers)as high thermal conductors,experimental and theoretical results of CNT-substrate interface resistance,and utilizations of CNTs in the passive heat dissipation(natural convection,heat radiation,and phase-change heat transfer).Finally,the challenges and prospects are discussed to provide some hints in the future *** is believed that CNTs can play an important role in thermal management of electronics,especially in the portable electronic devices.

关键词： carbon nanotubes thermal management passive heat dissipation thermal interface materials thermal interface resistance

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＂Takeaway＂ drug delivery： A new nanomedical paradigm

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Nano research 2017年第7期10卷 2234-2243页

作者： Elena Gonzalez-Domfnguez Benito Rodriguez-Gonzalez Moises Perez-Lorenzo Miguel A. Correa-Duarte Department of Physical Chemistry Biomedical Research Center (CINBIO) and Southern Galicia Institute of Health Research (IISGS)Universidade de Vigo 36310 Vigo Spain

An alternative model to the well-established paradigm of the externally switchable drug delivery systems is herein proposed. In contrast to the on--off archetype, here the amount of released drug is pre-set by the application of an external stimulus, and is gradually released after the withdrawal of the exogenous signal. These attributes are achieved through an innovative approach featuring the integration of plasmonic nanovehicles in a polymer-based film. Such a platform is provided with optically responsive capabilities together with multiple diffusional barriers, allowing for an ＂on-demand＂ time-limited release where light acts as a therapeutic ＂starting shot＂. These nanoarchitectured depots have great potential as implantable drug delivery systems in clinical scenarios where a recurrent, sustained, and yet, on--off administration of medication is required. The application of these hybrid materials may extend the implementation of nanomedicine strategies beyond the point-of-care setting.

关键词： release plasmonic nanocapsule hydrogel near infrared (NIR)

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Effect of impurity ions on preparation of novel saponifier for rare earth extraction

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Journal of Rare Earths 2013年第9期31卷 905-910页

作者：肖燕飞冯宗玉黄小卫黄莉徐旸侯永可王猛 National Engineering research center for Rare Earth Materials General Research Institute for Nonferrous MetalsGrirem Advanced Materials Co.Ltd.

Magnesium bicarbonate, prepared by the carbonation of magnesium hydroxide slurry, was used as a novel saponifier to eliminate the ammonia nitrogen pollution in the rare earth extraction separation process. The effect of impurity ions introduced by system on the carbonation reaction of magnesium hydroxide was studied in the work. The results showed that the presence of Ca2＋could lead to side reactions so as to reduce the conversion rate of magnesium hydroxide, and a small number of rare earth ions would have great influence on the carbonation reaction. What’s more, there was no influence on carbonation reaction with the low concen-tration of Na＋or Mg2＋, the conversion rate of magnesium hydroxide could reach above 96%. This paper showed a practical theory which could provide scientific guidance for the preparation of novel saponifier in rare earth extraction separation process.

关键词： rare earths magnesium bicarbonate saponifier carbonation impurity ions

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Effects of precursor moisture and inert N_2 atmosphere calcinations on structure and properties of alumina modified CeZrLaNd mixed oxides

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Journal of Rare Earths 2019年第6期37卷 609-616页

作者： Meisheng Cui Zhizhe Zhai Hao Wang Yongke Hou Yongqi Zhang Xiaowei Huang National Engineering research center for Rare Earth Materials General Research Institute for Nonferrous Metals Grirem Advanced Materials Co. Ltd.

CeO_2-ZrO_2 mixed oxides are widely used in the three-way catalysts due to their unique reversible oxygen storage and release capacity. Large surface area, high oxygen storage capacity and good thermal stability of cerium zirconium mixed oxides are the key properties for the automotive catalysts so as to meet the strict emission regulations. In this work, alumina modified CeZrLaNd mixed oxides were prepared by a co-precipitation method. The effects of moisture in precursor and inert N2 atmosphere during calcinations on the structure and properties were investigated by Brunauer-Emmett-Teller(BET) surface area measurements, X-ray diffraction(XRD), scanning electron microscopy(SEM), transmission electron microscopy(TEM), hydrogen temperature-programmed reduction(H_2-TPR), oxygen storage capacity(OSC), Raman spectroscopy, and X-ray photoelectron spectroscopy(XPS). The results show that the moisture in precursor during calcinations increases the crystal grain size of the cerium zirconium mixed oxides, improving the thermal stability. And the aged surface area of sample after being calcined at1000 ℃ for 4 h reaches 68.8 m^2/g(5.7% increase compared with the common sample). The inert N2 atmosphere endows a great pore-enlarging effect, which leads to high fresh surface area of 148.9 m2/g(13.5% increase compared with the common sample) and big pore volume of 0.5705 mL/g. The redox and oxygen storage capacity are also improved by inert N2 atmosphere with high OSC value of 241.06μmolO_2/g(41.3% increase compared with the common calcination), due to the abundant formation of the crystal defects and oxygen vacancies.

关键词： Precursor moisture Inert N2 atmosphere Calcinations Alumina modified CeZrLaNd mixed oxides Rare earths

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CGR3： A Golgi-Localized Protein Influencing Homogalacturonan Methylesterification

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Molecular Plant 2011年第5期4卷 832-844页

作者： Michael A. Held Evan Be Starla Zemelis Saunia Withers Curtis Wilkerson Federica Brandizzi great Lakes Bioenergy research center Michigan State University East Lansing MI 48824 USA MSU-DOE Plant research Lab Michigan State University East Lansing MI 48824 USA Present address： Department of Chemistry and Biochemistry Ohio University Athens OH 45701 USA Department of Biochemistry and Molecuiar Biology Michigan State University East Lansing MI 48824 USA

Plant cell walls are complex structures that offer structural and mechanical support to plant cells and are ultimately responsible for plant architecture and form. Pectins are a large group of complex polysaccharides of the plant cell wall that are made in the Golgi and secreted to the wall. The methylesterification of pectins is believed to be an important factor for the dynamic properties of the cell wall. Here, we report on a protein of unknown function discovered using an extensive proteomics analysis of cotton Golgi. Through bioinformatic analyses, we identified the ortholog of such protein, here named cotton Golgi-related 3 （CGR3） in Arabidopsis and found that it shares conserved residues with S- adenosylmethionine methyltransferases. We established that CGR3 is localized at the Golgi apparatus and that the expression of the CGR3 gene is correlated with that of several cell wall biosynthetic genes, suggesting a possible role of the protein in pectin modifications. Consistent with this hypothesis, immunofluorescence microscopy with antibodies for homogalacturonan pectins （HG） indicated that the celt wails of cgr3 knockout mutants and plants overexpressing CGR3 are decreased and increased in HG methylesterification, respectively. Our results suggest that CGR3 plays a role in the methylesterification of homogalacturonan in Arabidopsis.

关键词： Golgi methyltransferase homogalacturonan pectin.

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HuR and post-transcriptional regulation in vascular aging

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Science China(Life Sciences) 2014年第8期57卷 863-866页

作者： WANG WenGong research center on Aging Department of Biochemistry and Molecular BiologyPeking University Health Science Center

HuR(ELAV11(embryonic lethal,abnormal vision)-like 1),a ubiquitously expressed member of the ELAV-like RNA-binding protein family,has been shown to regulate the stability and translation of mRNAs that encode factors regulating cellular senescence,thereby impacting on *** this review,we discuss the current knowledge of HuR’s role in vascular cell senescence and vascular aging.

关键词： HuR mRNA turnover translation cell senescence vascular aging

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