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核桃楸树皮乙醇提取物的成分分析

应用化学 2008年第10期25卷 1205-1208页

作者：孙墨珑宋湛谦方桂珍东北林业大学理学院哈尔滨150040 中国林业科学研究院林产化学工业研究所东北林业大学材料科学与工程学院

采用常规提取法浸提核桃楸树皮的活性成分,采用GC-MS联用技术对核桃楸树皮乙醇提取物中氯仿萃取物和乙酸乙酯萃取物的化学组成和各成分进行分析。结果表明,核桃楸树皮乙醇提取物中氯仿萃取物的主要活性成分分别为:5-羟基-1,4-萘醌(胡桃... 详细信息

采用常规提取法浸提核桃楸树皮的活性成分,采用GC-MS联用技术对核桃楸树皮乙醇提取物中氯仿萃取物和乙酸乙酯萃取物的化学组成和各成分进行分析。结果表明,核桃楸树皮乙醇提取物中氯仿萃取物的主要活性成分分别为:5-羟基-1,4-萘醌(胡桃醌,质量分数36.65%),4-羟基-2-甲氧基肉桂醛,2,3-二氢苯并呋喃,香草醛,2-甲氧基-4-乙烯基苯酚。核桃楸树皮乙醇提取物中乙酸乙酯萃取物的主要活性成分分别为:1,2,3-苯三醇(质量分数42.31%),5-羟基-1,4-萘醌(胡桃醌,质量分数12.33%),7-甲氧基-1-四氢萘酮(质量分数11.26%),5-羟甲基-2-呋喃醛,3,4-二氢-6,7-二羟基-1(2H)-萘酮,4-羟基-2-甲氧基肉桂醛,D-阿洛糖。

关键词：核桃楸树皮提取物成分分析

碱木质素交联PVA共混啶虫脒缓释薄膜的制备及性能

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北京林业大学学报 2015年第12期37卷 116-121页

作者：任世学倪海月田金玲方桂珍东北林业大学材料科学与工程学院生物质材料科学与技术教育部重点实验室

以聚乙烯醇(PVA)和碱木质素为原料,交联剂为乙二醛,采用流延法制备碱木质素交联PVA共混啶虫脒缓释薄膜。采用傅里叶红外光谱方法对薄膜的化学结构进行分析,并表征薄膜的透气性和力学性能。通过单因素试验探索碱木质素与PVA质量比、乙二... 详细信息

以聚乙烯醇(PVA)和碱木质素为原料,交联剂为乙二醛,采用流延法制备碱木质素交联PVA共混啶虫脒缓释薄膜。采用傅里叶红外光谱方法对薄膜的化学结构进行分析,并表征薄膜的透气性和力学性能。通过单因素试验探索碱木质素与PVA质量比、乙二醛用量、啶虫脒用量对啶虫脒薄膜啶虫脒释放率的影响。结果表明:碱木质素与PVA成功交联,啶虫脒薄膜透氧气量增大,透二氧化碳量降低;啶虫脒薄膜的拉伸强度和断裂伸长率均比交联薄膜低。采用流延成膜法制备啶虫脒薄膜的最佳条件为碱木质素与PVA质量比3∶7、乙二醛用量1.5 m L、啶虫脒用量0.5 g,所制啶虫脒薄膜的啶虫脒释放率为31.8%。药水比例、温度对啶虫脒薄膜的释药快慢有一定影响。

关键词：木质素聚乙烯醇乙二醛啶虫脒缓释

交联碱木质素--聚乙烯醇基钾镁缓释膜肥对钾、镁的缓释性能

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北京林业大学学报 2014年第6期36卷 165-170页

作者：姜伟童于淼房雷刘玲徐良君苏玲方桂珍东北林业大学生物质材料科学与技术教育部重点实验室

为了提高工业碱木质素的利用率和扩大其应用范围,以工业碱木质素和聚乙烯醇（PVA）为原料、甲醛作为交联剂、添加硫酸钾和硫酸镁制备交联碱木质素-聚乙烯醇基钾镁缓释膜肥。采用FTIR-ATR方法测定缓释膜肥的化学结构,并用淋溶实验检验缓... 详细信息

为了提高工业碱木质素的利用率和扩大其应用范围,以工业碱木质素和聚乙烯醇（PVA）为原料、甲醛作为交联剂、添加硫酸钾和硫酸镁制备交联碱木质素-聚乙烯醇基钾镁缓释膜肥。采用FTIR-ATR方法测定缓释膜肥的化学结构,并用淋溶实验检验缓释膜肥对钾、镁的缓释作用。结果表明：1）缓释膜肥在3 260 cm-1左右的峰变小变宽,1 332.57 cm-1处吸收峰消失,1 145.51-983.52 cm-1范围内吸收峰变大,说明碱木质素、聚乙烯醇经甲醛交联有化学反应发生。2）与纯PVA交联薄膜相比,碱木质素的加入不利于钾的缓释,而适量的碱木质素有利于镁的缓释,碱木质素加入量可达20%。随着甲醛加入量的增大,钾累积释放率减小;适量甲醛有利于镁的缓释,但随着甲醛加入量的增大,缓释膜肥对镁的缓释性能降低。对镁的缓释,甲醛的合适加入量为3.59%。缓释膜肥对钾的缓释主要是分子结构的物理阻挡作用,而镁缓释除了物理阻挡作用还有木质素的螯合作用。3）对缓释膜肥的动力学试验数据进行拟合,钾缓释的4种模型拟合程度都很高,其中Higuchi模型拟合程度最高,决定系数为0.994 1,说明钾缓释行为遵循Fick扩散。镁缓释模型中Ritger-Peppas模型的拟合程度最高,决定系数为0.974 2,其缓释指数（0.5≤n≤1.0）表明镁缓释行为是扩散和溶蚀综合作用的结果。

关键词：碱木质素聚乙烯醇交联钾镁缓释

[Pt_2(P_2O_5H_2)_4]^(4-)和[Pt_2(P_2O_4CH_4)_4]^(4-)基态和激发态性质的理论研究

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无机化学学报 2007年第3期23卷 397-400页

作者：郭元茹潘清江方桂珍刘志明东北林业大学材料科学与工程学院哈尔滨150040 黑龙江大学化学化工与材料学院哈尔滨150080

采用从头计算MP2和CIS方法分别优化等电子双核d8配合物[Pt2(P2O5H2)4]4-和[Pt2(P2O4CH4)4]4-的基态和激发态结构。结果表明基态Pt-Pt距离分别为0.2905和0.2987nm,与实验的0.2925和0.2980nm符合。NBO计算的Pt-Pt键级以及Pt原子间伸缩振动说明Pt-Pt相互作用具有吸引本质。CIS计算揭示电子激发到Pt-Pt的σ(pz)成键轨道使得相互作用增强。保持激发态几何,含时密度泛函理论(TD-DFT)计算的溶液发射分别为449和475nm,与实验值512和510nm接近。

关键词：双核d^s配合物激发态从头计算含时密度泛函理论

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3-羰基-桦木酰-甘氨酸的合成与活性分析

北京林业大学学报 2011年第1期33卷 134-138页

作者：张小丽吕坤方桂珍田水清孔维东北林业大学材料科学与工程学院吉林大学生命科学学院

为了增强桦木酮酸的生物活性,以桦木酮酸为原料,草酰氯为酰化剂,合成桦木酮酸酰氯,再与甘氨酸甲酯盐酸盐合成3-羰基-桦木酰-甘氨酸甲酯,水解得到3-羰基-桦木酰-甘氨酸。采用红外、核磁和质谱对产物进行化学结构分析,并用四唑盐比色试验(... 详细信息

为了增强桦木酮酸的生物活性,以桦木酮酸为原料,草酰氯为酰化剂,合成桦木酮酸酰氯,再与甘氨酸甲酯盐酸盐合成3-羰基-桦木酰-甘氨酸甲酯,水解得到3-羰基-桦木酰-甘氨酸。采用红外、核磁和质谱对产物进行化学结构分析,并用四唑盐比色试验(MTT)法对人源肺腺癌细胞(A549)、人源鼻癌细胞(CNE)、人源舌鳞癌细胞(Tca8113)细胞株的细胞毒活性进行分析。结果表明:试验合成了3-羰基-桦木酰-甘氨酸,高效液相色谱检测合成产物纯度为97.8%;3-羰基-桦木酰-甘氨酸的半抑制浓度IC50值与桦木酸的半抑制浓度IC50值相比明显降低;对Tca8113细胞,3-羰基-桦木酰-甘氨酸的IC50值约为桦木酸IC50值的1/11;对CNE细胞,3-羰基-桦木酰-甘氨酸的IC50值约为桦木酸IC50值的1/53。由此说明3-羰基-桦木酰-甘氨酸在抑制肿瘤细胞生长的活性方面明显优于桦木酸。

关键词：桦木酮酸 3-羰基-桦木酰-甘氨酸肿瘤细胞生物活性

Excess Activity Tuned by Distorted Tetrahedron in CoMoO_(4) for Oxygen Evolution

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Energy & Environmental Materials 2024年第1期7卷 247-252页

作者： Hengbo Xiao Kai Chi Hongxia Yin Xiangji Zhou Pengxiang Lei Peizhi Liu Jiakun fang Xiuhong Li Songliu Yuan zhen Zhang Yaqiong Su Junjie Guo Lihua Qian School of Physics Huazhong University of Science and TechnologyWuhan 430074China Key Laboratory of Material Chemistry for Energy Conversion and Storage School of Chemistry and Chemical EngineeringHuazhong University of Science and TechnologyWuhan 430074China School of Chemistry and Chemical Engineering Hubei University of TechnologyWuhan 430068China Key Laboratory of Interface Science and Engineering in Advanced Materials Ministry of EducationTaiyuan University of TechnologyTaiyuan 030024China State Key Lab of Advanced Electromagnetic Engineering and Technology School of Electrical and Electronic EngineeringHuazhong University of Science and TechnologyWuhan 430074China School of Mechanical Engineering Hubei University of TechnologyWuhan 430068China Department of Stomatology Union HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430074China School of Chemistry Xi'an Jiaotong UniversityXi'an 710049China

Oxygen vacancies enable modulating surface reconstruction of transition metal oxides containing metal-oxygen polyhedrons into metallic oxyhydroxide for oxygen evolution reaction(OER),while revealing reconstructing mechanism is stuck by the requirement to precisely control exact sites of these ***,oxygen vacancies are localized only within MoO_(4)tetrahedrons rather than CoO_(6)octahedrons in CoMoO_(4)catalyst,guaranteeing coherent reconstruction of CoO_(6)octahedrons into pure CoOOH with tunable activities for ***,distorted tetrahedron accelerates the dissolution of Mo atoms into alkaline electrolyte,triggering spontaneous transition of partial CoMoO_(4)into Co(OH)_(2).CoO_(6)octahedrons in both CoMoO_(4)and Co(OH)_(2)can transform pure CoOOH completely at lower potential,resulting in excess intrinsic activity whose summit is identified by overpotential at 10 mA cm^(-2)with 22.9%reduction and Tafel slope with 65.3%***-defined manipulation over the distorted polyhedrons offers one versatile knob to precisely modulate electronic structure of oxide catalysts with outstanding OER performance.

关键词： metal-oxygen polyhedron oxygen evolution reaction oxygen vacancy Raman spectroscopy

Ca^(2+)-independent ZmCPK2 is inhibited by Ca^(2+)-dependent ZmCPK17 during drought response in maize

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Journal of Integrative Plant Biology 2024年第7期66卷 1313-1333页

作者： Xiaoying Hu Jinkui Cheng Minmin Lu Tingting fang Yujuan Zhu zhen Li Xiqing Wang Yu Wang Yan Guo Shuhua Yang Zhizhong Gong State Key Laboratory of Plant Environmental Resilience Frontiers Science Center for Molecular Design BreedingCenter for Crop Functional Genomics and Molecular BreedingCollege of Biological SciencesChina Agricultural UniversityBeijing 100193China College of Life Sciences Institute of Life Science and Green DevelopmentHebei UniversityBaoding 071002China

Calcium oscillations are induced by different ***-dependent protein kinases(CDPKs/CPKs)are one major group of the plant calcium decoders that are involved in various processes including drought *** CPKs are ***,we identified ZmCPK2 as a negative regulator of drought resistance by screening an overexpression transgenic maize *** found that ZmCPK2 does not bind calcium,and its activity is mainly inhibited during short term abscisic acid(ABA)treatment,and dynamically changed in prolonged ***,ZmCPK2 interacts with and is inhibited by calcium-dependent ZmCPK17,a positive regulator of drought resistance,which is activated by ***17 could prevent the nuclear localization of ZmCPK2 through phosphorylation of ***2 interacts with and phosphorylates and activates ZmYAB15,a negative transcriptional factor for drought *** results suggest that drought stress-induced Ca^(2+)can be decoded directly by ZmCPK17 that inhibits ZmCPK2,thereby promoting plant adaptation to water deficit.

关键词： CDPK drought response phosphorylation stomatal movement transcriptional regulation

CPL-active hybrid copper(Ⅰ)halides enabled by cation inclusion with chiral crown-ether

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Science China Chemistry 2024年第10期67卷 3283-3290页

作者： Peng Fan Li-Xuan Cai Xiao-fang Duan Fan Yin Chen-Chen Li Zhong-Hua Deng Xiao-zhen Li Qing-Fu Sun College of Chemistry and Materials Science Fujian Normal UniversityFuzhou 350117China Strait Institute of Flexible Electronics(Future Technologies) Fujian Key Laboratory of Flexible ElectronicsFujian Normal University and Strait Laboratory of Flexible ElectronicsFuzhou 350117China State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002China Fujian College University of Chinese Academy of SciencesFuzhou 350002China

Chiral hybrid metal halides with high photoluminescence quantum yield(PLQY)and superior dissymmetry factor(g_(lum))are promising candidates for circularly polarized luminescence(CPL)emitting ***,it is a great challenge to achieve both high g_(lum)and large ***,we report a new supramolecular strategy to fabricate chiral hybrid Cu(Ⅰ)-halides with nearunity quantum yields and intense CPL *** dissymmetry factor can be dramatically modulated by tuning the hostguest *** to the chirality and variable conformations of the host-guest complexes,a series of chiral[G@L^(R/S)]_(2)Cu_(4)I_(6)have been *** incorporation of different cations within the chiral L^(R/S)hosts leads to variations of packing modes along the c-axis and different extent of distortions in the[Cu_(4)I_(6)]_(2)-*** them,[H_(3)O@L^(R/S)]+cations are stacked based on Van der Waals interactions and hierarchically self-assemble into a right/left-handed helix in[H_(3)O@L^(R/S)]_(2)Cu_(4)I_(6),which results in a high g_(lum)of-7×10^(-3)and a large PLQY of 96.92%.Notably,[G@L^(R/S)]_(2)Cu_(4)I_(6)shows promising applications in single-component white light emitting diodes(WLEDs),exhibiting a maximum dissymmetry factor of-1.2×10^(-3).The effective host-guest complexation and oriented hierarchical self-assembly provide an effective strategy for the development of high-performance CPL materials.

关键词： host-guest interaction circularly polarized luminescence copper iodide cluster hierarchical self-assembly chirality

Intermediate-mass black holes in Green pea galaxies(IMBH-GP)I:A candidate sample from LAMOST and SDSS

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Science China(Physics,Mechanics & Astronomy) 2024年第10期67卷 147-161页

作者： Ruqiu Lin zhen-Ya zheng fang-Ting Yuan Jun-Xian Wang Chunyan Jiang Ning Jiang Lingzhi Wang Linhua Jiang Xiang Ji Shuairu Zhu Xiaodan Fu Key Laboratory for Research in Galaxies and Cosmology Shanghai Astronomical ObservatoryChinese Academy of SciencesShanghai 200030China School of Astronomy and Space Sciences University of Chinese Academy of SciencesBeijing 100049China CAS Key Laboratory for Research in Galaxies and Cosmology Department of AstronomyUniversity of Science and Technology of ChinaHefei 230026China Chinese Academy of Sciences South America Center for Astronomy(CASSACA) National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China CAS Key Laboratory of Optical Astronomy National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China Kavli Institute for Astronomy and Astrophysics Peking UniversityBeijing 100871China Department of Astronomy School of PhysicsPeking UniversityBeijing 100871China

The scaling relation of central massive black holes(M_(BH)s)and their host galaxies is well-studied for supermassive BHs(SM_(BH)s,M_(BH)≥10^(6)M_(⊙)).However,this relation has large uncertainties in the mass range of the intermediate-mass BHs(IM_(BH)s,M_(BH)~10^(3)-10^(6)M_(⊙)).Since Green pea(GP)galaxies are luminous compact dwarf galaxies,which may be likely to host less massive SM_(BH)s or even IM_(BH)s,we systematically search for M_(BH)s in a large sample of 2190 GP galaxies at z<0.4,selected from LAMOST and SDSS spectroscopic ***,we report a newly discovered sample of 59 M_(BH) candidates with broad Hα*** sample has a median stellar mass of 108.83±0.11M_(⊙)and hosts M_(BH)s with single-epoch virial masses ranging from M_(BH)~10^(4.7)to 10^(8.5)M_(⊙)(median 105.85±0.64M_(⊙)).Among the 59 M_(BH) candidates,36 have black hole masses M_(BH)≤10^(6)M_(⊙)(IM_(BH) candidates),one of which even has M_(BH)■10^(5)M_(⊙).We find that the M_(BH)-M_(*)relation of our M_(BH) sample is consistent with the M_(BH)-M_(bulge)relation for SM_(BH)s,while is above the M_(BH)-M_(*)relation for M_(BH)s in dwarf galaxies in the same mass ***,we show that 25 M_(BH) candidates,including 4 IM_(BH) candidates,have additional evidence of black hole activities,assessed through various methods such as the broad-line width,BPT diagram,mid-infrared color,X-ray luminosity,and radio *** studies show that it is very promising to find IM_(BH)s in GP galaxies,and the BH sample so obtained enables us to probe the connection between the M_(BH)s and compact dwarf galaxies in the low-redshift Universe.

关键词： SMBHs IMBHs Green pea galaxies compact dwarf galaxies