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Preparation of Aryloxy-aluminoxanes and Their Use as Activators in the Bis(imino)pyridyl Iron-catalyzed Oligomerization of Ethylene

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Chinese Journal of Polymer Science 2018年第11期36卷 1207-1207,1208-1216页

作者： Wei Zhang Bin-Bo Jiang Jian Ye Zu-Wei Liao Zheng-Liang Huang Jing-Dai Wang Yong-Rong Yang Zhejiang Provincial Key Laboratory of Advanced Chemical Engineering Manufacture Technology State Key Laboratory of Chemical Engineering College of Chemical and Biological Engineering Zhejiang University

In this study, a series of aryloxy-aluminoxanes originated directly from the hydrolysis of reaction products of A1Me3 and phenols were synthesized, which could serve as effective polymer-retarding activators for the iron-catalyzed ethylene oligomerization. The molar ratios of [PhOH]/[AlMe3] and [H2O]/[Al] during the preparation were explored and their impacts on the oligomerization activity and product distribution were discussed. To obtain the effective activators with good polymer-retarding effect and relatively high activity, the optimized conditions were proposed to be [PhOH]/[AlMe3] = 0.5 and [H2O]/[Al] = 0.7. Various aluminoxanes with different [-OH] sources confirmed the importance of using phenols in preparing the effective polymer-retarding activators. By utilizing these aryloxy-aluminoxanes, the mass fraction of polymers in the total products could be reduced to lower than 1.0 wt%, which is much lower than that of the MAO-activated systems （〉 30 wt%）. This is a potential benefit for the industrial application of the iron-catalyzed oligomerization process.

关键词： Ethylene oligomerization Bis(imino)pyridyl iron catalysts Aryloxy-aluminoxanes phenols Trimethylaluminum hydrolysis

水中痕量酚的富集和紫外分光光度测定法的研究

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分析化学 1989年第2期17卷 107-111页

作者：王丽丽刘汉成徐雪松徐立红鞠岗陶蕾芬杭州本院86届毕业生杭州本院87届毕业生浙江工学院化工系浙江工学院化工系杭州

本文研究了用微型树脂柱快速富集,分离,紫外分光光度测定水中痕量酚的方法。结果表明,以GDX-502为吸附剂,水样pH为1～3并含0.2mol/L氯化钠,以每分种15～20ml的速度通过吸附柱,以热的1％氢氧化钠水溶液为淋洗剂时,在291nm处测定苯酚的回... 详细信息

本文研究了用微型树脂柱快速富集,分离,紫外分光光度测定水中痕量酚的方法。结果表明,以GDX-502为吸附剂,水样pH为1～3并含0.2mol/L氯化钠,以每分种15～20ml的速度通过吸附柱,以热的1％氢氧化钠水溶液为淋洗剂时,在291nm处测定苯酚的回收率为89～98％。此外探讨了干扰物的消除方法。吸附柱对苯酚的富集倍数达300倍,最低检测限为0.001ppm。方法精密度为0.3(％),相对标准偏差为3.18％。本法对实际水样进行了测定。结果满意。

关键词： phenols Spectrophotemetry Enrichment Solid-Surface adsorption Thenolate ions

Synthesis and Crystal Structure of the Derivative of Hydroquinone from Mannich Reaction

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Chinese Journal of Structural Chemistry 2005年第3期24卷 311-314页

作者：马朋高张明杰杨启超于九皋 DepartmentofChemistry SchoolofScienceTianjinUniversityTianjin300072China DepartmentofChemistry NanyangTeachers＇CollegeNanyangHenan473061China

The regioselective Mannich-type aminomethylation of hydroquinone afforded a nitrogen-containing compound, 2,5-bis-(morpholinomethyl)hydroquinone A, and its crystal structure was determined by single-crystal X-ray diffraction. Crystal data for A: C16H24N2O4, Mr = 308.37, orthorhombic, space group Pbca, a = 10.479(4), b = 10.298(4), c = 14.865(5) ?, V = 1604.3(11) ?3, Z = 4, Dc = 1.277 g/cm3, F(000) = 664, μ = 0.092 mm-1, GOF = 1.078, the final R = 0.0508 and wR = 0.1075 for 1416 observed reflections with I > 2σ(I). There exist two intramolecular O–H…N hy- drogen bonds between the phenolic O atoms and the morpholine N donors and the morpholino rings assume the preferred chair conformation.

关键词： Mannich reactions phenols aminomethylation crystal structure

In vitro germination and shoot proliferation of the threatened species Cinchona officinalis L(Rubiaceae).

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Journal of Forestry Research 2016年第6期27卷 1229-1236页

作者： Rosa Armijos-Gonzalez Cesar Perez-Ruiz Departamento de Ciencias Naturales Universidad Tecnica Particular de LojaCP 1101 608 LojaEcuador Departamento de Biotecnologia y Biologia Vegetal E.T.S.Ingenieros AgronomosUniversidad Politecnica de MadridCP 728040 MadridSpain

Cinchona officinalis （Rubiaceae） is an endemic species of the Loja Valley in southern Ecuador with medicinal uses. Because of over-exploitation in the nine- teenth century and more recent disturbances to its ecosystem, C. officinalis populations are threatened. Currently, natural regeneration of the populations is low, despite its high plant regeneration and seed formation capacity. In the present study, an efficient protocol for germination, shoot proliferation and plantlets regeneration was developed for this species. Phenolic content and germination rate of C. officinalis seeds were compared with a control species, C. pubescens. Nodal segments from seedlings of C. officinalis were cultured on Gamborg medium supplemented with different combinations of plant growth regulators. Because the phenol content is high in C. officinalis, the phenolic should be removed with hydrogen peroxide or water washes to stimulate germination. Shoots and callus developed from nodal segments within 45 days using most of the tested combinations of plant growth regulators. The best rates of shoot proliferation, callus formation and adventitious buds were obtained in medium supplemented with 5.0 mg L^-1 6-benzyl-aminopurine and 3.0 mg L^-1 indole- 3-butyfic acid.

关键词： Callus Cinchona officinalis Germination phenols Rubiaceae Shoot

Biochemical changes associated with flowering in Bambusa arundinacea and Bambusa nutans

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Journal of Forestry Research 2018年第5期29卷 1315-1320页

作者： Pramod Kumar Yogeshwar Mishra Tropical Forest Research Institute Jabalpur Madhya Pradesh 482021 India

Biochemical changes associated with flowering in Bambusa arundinacea Linn and Bambusa nutans *** Munro were *** flowering was initiated in natural areas and plantations of *** in late 2014 and reached full bloom in early 2015,whereas sporadic flowering recorded during 2014–2015 in vegetatively propagated plants of *** and nodal shoot samples from flowering culms/shoots and nonflowering culms/shoots were collected in February 2015 at the initiation of fruit filling,then analyzed and compared for soluble sugars,phenols and peroxidase *** both species sugars were higher in leaves of flowering culms/shoots and lower in nodal shoots of flowering culms/shoots compared to the *** were lower in leaves and nodal shoots of flowering ***,but higher in leaves and decreases in nodal shoots of *** activity increases in leaves and nodal shoots of *** after flowering but increases in nodal shoots and decreases in leaves of ***.

关键词： Sugars phenols Peroxidase activity Flowering Bambusa arundinacea Bambusa nutans

Edible seaweed-derived constituents: an undisclosed source of neuroprotective compounds

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Neural Regeneration Research 2020年第5期15卷 790-795页

作者： Melissa Schepers Nikita Martens Assia Tiane Kenneth Vanbrabant Hong-Bing Liu Dieter Lütjohann Monique Mulder Tim Vanmierlo Department of Neuroimmunology Biomedical Research InstituteHasselt UniversityEuropean Graduate School of Neuroscience (EURON)HasseltBelgium Department of Psychiatry & Neuropsychology Division of Translational NeuroscienceSchool for Mental Health and NeuroscienceMaastricht UniversityEuropean Graduate School of Neuroscience (EURON)MaastrichtThe Netherlands Department of Internal Medicine Laboratory of Vascular MedicineErasmus MC University Medical CenterRotterdamthe Netherlands Institue for Clinical Chemistry and Clinical Pharmacology BonnGermany Key Laboratory of Marine Drugs Ministry of EducationSchool of Medicine and PharmacyOcean University of ChinaQingdaoShandong ProvinceChina

Edible marine algae,or seaweeds,are a rich source of several bioactive compounds including phytosterols,carotenoids,and *** the last decades,seaweed-derived constituents turned out to not only reside in the systemic circulation,but are able to cross the blood-brain barrier to exert neuro-active functions both in homeostatic and pathological ***,seaweed-derived constituents have gained increasing interest for their neuro-immunomodulatory and neuroprotective properties,rendering them interesting candidates for the management of several neurodegenerative *** particular seaweed-derived phytosterols gained interest for the treatment of neurodegenerative disorders as they potentiate neuroplasticity,enhance phagocytic clearance of neurotoxic peptides and have anti-inflammatory ***,the anti-inflammatory and anti-oxidative properties of other constituents including carotenoids,phenols and polysaccharides have recently gained more *** this review,we provide an overview of a selection of the described neuro-active properties of seaweed-derived constituents with a focus on phytosterols.

关键词： algae carotenoids neuro-active phenols phytosterols polysaccharides seaweed

Achieving UV and visible-light photocatalytic activity enhancement of AgI/BiOIO3 heterostructure:Decomposition for diverse industrial contaminants and high mineralization ability

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Chinese Chemical Letters 2017年第12期28卷 2244-2250页

作者： Fang Chen Hongwei Huang Yihe Zhang Tierui Zhang Beijing Key Laboratory of Materials Utilization of Nonmetallic Minerals and Solid Wastes National Laboratory of Mineral Materials School of Materials Science and Technology China University of Geosciences Key Laboratory of Photochemical Conversion and Optoelectronic Materials Technical Institute of Physics and Chemistry Chinese Academy of Sciences

Heterostructure photocatalyst fabrication is of great significance for promoting the photoreactivity and solar-energy utilization efficiencies. In this work, AgI/BiOIOheterostructure photocatalysts are synthesized by a facile in-situ crystallization of AgI on BiOIO. The photocatalytic performance is first surveyed by decomposition of model dye methyl orange(MO) separately with illumination of UV light and visible-light(λ> 420 nm). It indicates that AgI/BiOIOshows highly improved photocatalytic activity regardless of the light source, which should be attributed to the matchable band energy levels between AgI and BiOIO, benefiting the efficient charge separation. Notably, AgI/BiOIOshows a universal photocatalytic activity for treating diverse antibiotics and phenols, including tetracycline hydrochloride,chlortetracycline hydrochloride, 2,4-dichlorophenol(2,4-DCP), phenol and bisphenol A(BPA), and the strong mineralization ability of AgI/BiOIOwas also demonstrated. Additionally, the different mechanisms under UV and visible light irradiation are investigated in detail. This work provides a new reference for design and manipulation of high-performance nonselective heterostructure photocatalyst for environmental purification.

关键词： Photocatalysis Heterostructure BiOIO3 AgI Antibiotics phenols

Partitioning between primary and secondary metabolism of carbon allocated to roots in four maize genotypes under water deficit and its effects on productivity

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The Crop Journal 2015年第5期3卷 379-386页

作者： Alyne Oliveira Lavinsky Paulo Cesar Magalhaes Roniel Geraldo avila Mariana Melo Diniz Thiago Correa de Souza Embrapa Milho e Sorgo Sete LagoasMGCEP:35701-970Brazil Universidade Federal de Lavras LavrasMGCEP 37200-000Brazil Universidade Federal de Sao Joao Del Rey Sete LagoasMGCEP 35701-970Brazil Universidade Federal de Alfenas AlfenasMGCEP 37130-000Brazil

Plants may respond to drought by altering biomass allocation to shoots and roots or by changing the metabolic activities in these organs. To determine how drought changes the partitioning of carbon allocated to growth and secondary metabolism in maize roots and how it affects photosynthesis(A) and productivity in maize, we evaluated leaf gas exchange, yield componentes, root morphology, and primary and secondary metabolites including total soluble sugars(TSS), starch(S), phenolics(PHE), and lignin(LIG). Data were collected from pot-grown plants of four maize genotypes: BRS 1010 and 2B710(sensitive genotypes) and DKB390 and BRS1055(tolerant genotypes) under two soil water tensions: field capacity(FC,-18 kP a) and water deficit(WD,-138 kP a). WD was applied at the pre-flowering stage for 12 days and then the water supply was restored and maintained at optimum levels until the end of the cycle. For genotype BRS 1055 under FC, the greatest A did not result in greater grain biomass(DGB) because the accumulated photoassimilates had already filled the cells, and thus the excessive TSS synthesized in leaves was allocated to roots in large amounts. However, the sharp decrease in A caused by WD imposition in this genotype did not affect the influx pressure of leaf TSS, which was due largely to conversion of primary metabolites to PHE compounds to increase the length of fine roots. In leaves of DKB390 under WD, both S and TSS were reduced, whereas PHE were increased to prevent excessive water loss and xylem cavitation. Under WD, both BRS1010 and2B710 genotypes displayed reduced allocation of biomass to shoots and roots and LIG content in leaves, as well as lower A and DGB values. In BRS1010 this response was coupled to S decrease in leaves and TSS increase in roots, whereas in 2B710 there was a concomitant S increase in roots.

关键词： Starch Sugars Lignin phenols WinRHIZO

Changes in properties of tar obtained during underground coal gasification process

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International Journal of Coal Science & Technology 2021年第5期8卷 1054-1066页

作者： Marian Wiatowski Roksana Muzyka Krzysztof Kapusta Maciej Chrubasik Central Mining Institute Plac Gwarków 140-166 KatowicePoland Institute for Chemical Processing of Coal 1 Zamkowa St41-803 ZabrzePoland

In this study,the composition of tars collected during a six-day underground coal gasification(UCG)test at the experimental mine‘Barbara’in Poland in 2013 was *** the test,tar samples were taken every day from the liquid product separator and analysed by the methods used for testing properties of typical coke oven(coal)*** obtained results were compared with each other and with the data for coal *** gasification progressed,a decreasing trend in the water content and an increasing trend in the ash content were *** tars tested were characterized by large changes in the residue after coking and content of parts insoluble in toluene and by smaller fluctuations in the content of parts insoluble in *** tested samples were characterized by very high distillation losses,while for samples starting from the third day of gasification,a clear decrease in losses was visible.A chromatographic analysis showed that there were no major differences in composition between the tested tars and that none of the tar had a dominant component such as naphthalene in coal *** content of polycyclic aromatic hydrocarbons(PAHs)in UCG tars is several times lower than that in coal *** light monoaromatic hydrocarbons(benzene,toluene,ethylbenzene and xylenes—BTEX)were found in the analysed tars,which results from the fact that these compounds,due to their high volatility,did not separate from the process gas in the liquid product separator.

关键词： Underground coal gasification UCG Pilot trial Tar BTEX PAHs phenols