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名校长工作室TRIMER研修模式助力乡村区域教育质量提升——以保定市贫困县(脱贫县)系列名校长工作室为例 被引量:1
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作者 陈丽 《继续教育研究》 2022年第4期103-106,共4页
如何以名校长工作室方式助推乡村教育质量提升,河北省保定市贫困县(脱贫县)系列名校长工作室项目组形成的TRIMER(三聚体)研修模式进行了很好的探索。TRIMER模式在研修功能定位上强调校长成长、学校提质与区域教育优化三位一体;在研修方... 如何以名校长工作室方式助推乡村教育质量提升,河北省保定市贫困县(脱贫县)系列名校长工作室项目组形成的TRIMER(三聚体)研修模式进行了很好的探索。TRIMER模式在研修功能定位上强调校长成长、学校提质与区域教育优化三位一体;在研修方式上,培训、改进、辐射等三线交织;在研修原则上,培训与改进、个人研修与团队研修、素养提升与辐射带动有机结合;在培养主体上,保定市本土优秀校长的示范、北京市双导师的引领与京保教育行政的保驾护航相得益彰;在运行力量上,行政力量、学术力量、校长自我发展力量密切配合。 展开更多
关键词 乡村教育振兴 名校长工作室 trimer模式
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One New A-type Proanthocyanidin Trimer from Lindera aggregata(Sims) Kosterm. 被引量:3
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作者 ChaoFengZHANG QiShiSUN +1 位作者 ZhengTaoWANG MasaoHATTOR 《Chinese Chemical Letters》 SCIE CAS CSCD 2003年第10期1033-1036,共4页
One new A - type proanthocyanidin trimer, lindetannin trimer, was isolated from the stems of Lindera aggregata (Sims) Kosterm.. Its structure was elucidated by spectral and chemical methods.
关键词 Lindera aggregata LAURACEAE TANNIN lindetannin trimer.
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Insight into Medicinal Chemistry Behind Traditional Chinese Medicines: p-Hydroxybenzyl Alcohol-Derived Dimers and Trimers from Gastrodia elata 被引量:6
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作者 Yanan Wang Min Zhang +7 位作者 Xue Zhou Chengbo Xu Chenggen Zhu Yuhe Yuan Naihong Chen Yongchun Yang Qinglan Guo Jiangong Shi 《Natural Products and Bioprospecting》 CAS 2021年第1期31-50,共20页
From an aqueous extract of“tian ma”(the steamed and dried rhizomes of Gastrodia elata),ten new compounds gastrodiben-zins A−D(1−4)and gastrotribenzins A−F(5−10),along with known analogues(11−20),having structure fea... From an aqueous extract of“tian ma”(the steamed and dried rhizomes of Gastrodia elata),ten new compounds gastrodiben-zins A−D(1−4)and gastrotribenzins A−F(5−10),along with known analogues(11−20),having structure features coupling between two and three p-hydroxybenzyl-derived units via carbon-and/or ether-bonds,were isolated and characterized by spectroscopic data analysis.Meanwhile,the new compounds 5a,6a,8a,22,and 23,as well as the known derivatives 13a,14a,15,17−21,24,25,and p-hydroxybenzyl aldehyde were isolated and identified from a refluxed aqueous solution of p-hydroxybenzyl alcohol.Methylation of 5a and 6a in methanol and ethylation of 6a,8a,13a,and 14a in ethanol produced 5 and 6 and 7,8,13,and 14,respectively.using ultra-performance liquid chromatography high-resolution electrospray ioniza-tion mass spectrometry(UPLC-HRESIMS)analysis of the refluxed solutions of p-hydroxybenzyl alcohol and the refluxed extracts of the fresh G.elata rhizome and“tian ma”extracts indicated consistent production and variation of the dimeric and trimeric derivatives of p-hydroxybenzyl alcohol upon extracting solvents and refluxing time.In various assays,the dimeric and trimeric derivatives showed more potent activities than p-hydroxybenzyl alcohol itself and gastrodin,which are the main known active constituents of“tian ma”.These results revealed for the first time that the more effective dimers and trimers can be produced through condensation of the co-occurring p-hydroxybenzyl alcohol during processing and decocting of the G.elata rhizomes,demonstrating insights into medicinal chemistry behind application protocols of traditional Chinese medicines. 展开更多
关键词 ORCHIDACEAE Gastrodia elata p-Hydroxybenzyl alcohol dimer p-Hydroxybenzyl alcohol trimer Gastrodibenzins Gastrotribenzins Medicinal chemistry behind Chinese medicines
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Synthesis, Crystal Structure and Gas Adsorption of a Trimeric Nickel-based Coordination Polymer 被引量:2
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作者 王敏 卓超 +1 位作者 贺亮 林启普 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2019年第3期345-350,共6页
A trimeric porous coordination framework [Ni_3(TPTC)(IN)_2(μ_2-H_2O)_2(CH_3OH)_2)]n· x(solvents)(1, TPTC = terphenyl-3,3?,5,5??-tetracarboxylic acid, IN = isonicotinic acid) was synthesized and characterized by ... A trimeric porous coordination framework [Ni_3(TPTC)(IN)_2(μ_2-H_2O)_2(CH_3OH)_2)]n· x(solvents)(1, TPTC = terphenyl-3,3?,5,5??-tetracarboxylic acid, IN = isonicotinic acid) was synthesized and characterized by elemental analysis, infrared spectroscopy, thermogravimetric analysis, single-crystal and powder X-ray diffraction. It crystallizes in monoclinic space group C2/c with a = 33739(12), b = 14.820(5), c = 13.568(5) ?, β = 97.388(6)o, V = 6728(4) ?3, Z = 4, Mr = 965.35, Dc = 0.953 g·cm^(-3), F(000) = 1955.5, μ = 0.881 mm^(–1), GOOF = 1.072, the final R = 0.0859 and w R = 0.2424 for 5284 observed reflections with I > 2σ(I). The structure of 1 is constructed from the linkage of trinuclear {Ni_3} second building units through TPTC and IN spacers, forming a 4,8-connected network of Schl?fli symbol {32.42.52}{34.46.58.68.72}. The CO2 uptake values for 1 are 97.9 m^2·g^(-1) at 273 K and 66.2 m^2·g^(-1) at 298 K, while its N_2 adsorption values are 8.5 m^2·g^(-1) at 273 K and 4.9 m^2·g^(-1) at 298 K, respectively. These results show that 1 has high CO_2/N_2 adsorption selectivity at ambient conditions. 展开更多
关键词 trimeric NICKEL COMPLEX CRYSTAL structure GAS ADSORPTION
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Dimer与Trimer的量子统计力学 被引量:1
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作者 娄平 郭志椿 《安徽大学学报(自然科学版)》 CAS 1989年第1期37-43,共7页
本文根据Dimer与Trimer的特性,提出一个非理想量子气体的模型,并求得玻色子系统三阶维里系数的近似表达式。对~4He系统进行了具体计算,结果与实验值相符。
关键词 二聚物 三聚物 量子统计
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Toughening Modification of Unsaturated Polyester Resin Using HDI Trimer 被引量:1
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作者 段华军 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2009年第4期627-630,共4页
HDI trimer was firstly used to improve the mechanical properties of hydroxyl-terminated unsaturated polyester (UP). Mechanical properties measurements performed on the cured materials demonstrate a distinct improvem... HDI trimer was firstly used to improve the mechanical properties of hydroxyl-terminated unsaturated polyester (UP). Mechanical properties measurements performed on the cured materials demonstrate a distinct improvement in intensity and toughness in the presence of HDI trimer and shows the change trends of increase and then decrease. The morphological analysis of the fracture surfaces shows that the micro-phase separated structures appear in modified UPR systems and changed from dendritric, dimple and to cystiform structures with the increase of HDI trimer content. The presence of the cystiform structures made the modified UPR systems present the best properties. 展开更多
关键词 HDI trimer unsaturated polyester TOUGHNESS mechanical properties MORPHOLOGY
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Synthesis and Crystal Structure of a New μ-Oxamide Trimeric Hetero-tetranuclear Complex 被引量:1
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作者 CHENJing GAODong-Zhao WANGShu-Ping 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2005年第7期793-798,737,共7页
A novel oxamide-bridged trimeric tetranuclear complex 1 incorporating a macro- cyclic oxamide of formula {[(CuL)3Mn](ClO4)2}3 (macrocyclic oxamide L = 2,3-dioxo-5,6,14,15- dibenzo-1,4,8,12-tetraazacyclopentadeca-7,12-... A novel oxamide-bridged trimeric tetranuclear complex 1 incorporating a macro- cyclic oxamide of formula {[(CuL)3Mn](ClO4)2}3 (macrocyclic oxamide L = 2,3-dioxo-5,6,14,15- dibenzo-1,4,8,12-tetraazacyclopentadeca-7,12-diene) was prepared and structurally characterized. The compound [(CuL)3Mn](ClO4)2 crystallizes in the trigonal system, space group P 3 with a = 22.434(17), b = 22.434(17), c = 18.82(2) ?, α = β = 90, γ = 120o, V = 8203(13) ?3, Z = 6, Dc = 1.751g/cm3, μ(MoKα) = 1.557, F(000) = 4392, the final R = 0.083 and wR = 0.1727 for 9604 obser- ved reflections with I > 2σ(I). The single-crystal X-ray analysis shows that 1 is a trimeric complex. There are three similar constitutes, dissimilar conformations and asymmetrically independent ‘building-block’ [(CuL)3Mn] in one crystal cell of the title complex 1. 展开更多
关键词 SYNTHESIS crystal structure trimer μ-oxamido bridge hetero-tetranuclear
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Investigation of Light-harvest Material:Synthesis and Characterization of Nanometer Porphyrin Trimer 被引量:1
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作者 SHIYing-yan WANGXing-qiao +4 位作者 LIXiang-qing ZHENGWen-qi DINGHong ZHUGuang-shan LIUGuo-fa 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2004年第3期262-265,共4页
ω -Bromopropylporphyrin ether synthesized from the raction of 1,3-dibromopropane as the bridge-linked reagent and 5-(4-hydroxyphenyl)-10,15,20-triphenylporphyrin (H_2MHTPP) as the matrix reacts with 5,15-di(4- hydrox... ω -Bromopropylporphyrin ether synthesized from the raction of 1,3-dibromopropane as the bridge-linked reagent and 5-(4-hydroxyphenyl)-10,15,20-triphenylporphyrin (H_2MHTPP) as the matrix reacts with 5,15-di(4- hydroxyphenyl)-10,20-diphenyl porphyrin( trans -H_2DHDPP) to give the title nanometer porphyrin trimer. The characterization was carried out by means of elemental analyses,UV-Vis,IR, 1H NMR and XRD. 展开更多
关键词 Nanometer porphyrin trimer ω -Bromopropylporphyrin ether Bridge-linking reagent
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Fluorescence and Thermostability of Nanometer Porphyrin Trimer
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作者 SHI Ying-yan FA Huan-bao +3 位作者 ZHENG Wen-qi LI Di SHAN Ning WANG Xing-qiao 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2006年第1期14-16,共3页
A nanometer porphyrin trimer was firstly synthesized with 1 ,3-dibromopropane as a bridge-linked agent and the fluorescence property and thermostability were studied. The results show that the fluorescence property an... A nanometer porphyrin trimer was firstly synthesized with 1 ,3-dibromopropane as a bridge-linked agent and the fluorescence property and thermostability were studied. The results show that the fluorescence property and thermostability of the trimer are different from those of monoporphyrin. The effects of the molecule structure on the optical property and the thermostability were also studied in detail. 展开更多
关键词 Monoporphyrin Porphyrin trimer FLUORESCENCE Thermostability
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Synergistic effect of salts on inducingobvious viscoelastic behavior of cationic trimeric surfactant solutions
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作者 穆瑞花 吴文辉 《Journal of Beijing Institute of Technology》 EI CAS 2014年第3期420-426,共7页
A viscoelastic system formed by the solutions of di(2-hydroxyl-dimethylene ether)-α,ω, y-triple ( dimethyloctadecylammonium chlorine ) ( 18-4 ( OH ) -18-4 ( OH ) -18 ) is proposed to solve the problems of ... A viscoelastic system formed by the solutions of di(2-hydroxyl-dimethylene ether)-α,ω, y-triple ( dimethyloctadecylammonium chlorine ) ( 18-4 ( OH ) -18-4 ( OH ) -18 ) is proposed to solve the problems of poor temperature and shear resistances of clean fracturing fluid. The apparent viscosity of 18-4( OH)-18-4( OH)-18 solution affected by inorganic salt, hydrotropic salt and their mixtures is investigated using steady state measurements. Meanwhile, the temperature and shear resistances of systems of 18-4( OH)-18-4( OH)-18 and several common single-chain surfactants are compared. The rheological experiments show that, the coexistence of NaSal and NaC1 makes it easier for the system to promote micellar growth yielding wormlike micelles than single NaSal or NaC1. The apparent vis- cosity of 18-4(OH) -18-4(OH) -18 solution maintains over 87. 5 mPa-s above 100 22. The results indi- cate that there exists a synergistic effect in solutions of 18-4 ( OH ) -18-4 ( OH ) -18 trimeric surfactant 展开更多
关键词 cationic trimeric surfactant rheological property synergistic effects hydrotropic salt
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Exciton transfer dynamics in a trimer system
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作者 谭庆收 许兰 匡乐满 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第1期84-87,共4页
We study exciton transfer dynamics in a trimer system by investigating excitation transfer probability (ETP). We calculate ETP in the zero-temperature limit and theoretically predict the environment-assisted quantum... We study exciton transfer dynamics in a trimer system by investigating excitation transfer probability (ETP). We calculate ETP in the zero-temperature limit and theoretically predict the environment-assisted quantum critical effect, in which ETP exhibits a sudden change at the critical point of quantum phase transition for the trimer. In particular, we find that the steady-state ETP can be observed in the presence of the environment interaction. 展开更多
关键词 exciton transfer quantum phase transition trimer system
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Off-site trimer superfluid on a one-dimensional optical lattice
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作者 范二女 Tony C Scott 张万舟 《Chinese Physics B》 SCIE EI CAS CSCD 2017年第4期168-173,共6页
The Bose-Hubbard model with an effective off-site three-body tunneling,characterized by jumps towards one another,between one atom on a site and a pair atoms on the neighborhood site,is studied systematically on a one... The Bose-Hubbard model with an effective off-site three-body tunneling,characterized by jumps towards one another,between one atom on a site and a pair atoms on the neighborhood site,is studied systematically on a one-dimensional(1D) lattice,by using the density matrix renormalization group method.The off-site trimer superfluid,condensing at momentum k = 0,emerges in the softcore Bose-Hubbard model but it disappears in the hardcore Bose-Hubbard model.Our results numerically verify that the off-site trimer superfluid phase derived in the momentum space from[Phys.Rev.A81,011601(R)(2010)]is stable in the thermodynamic limit.The off-site trimer superfluid phase,the partially off-site trimer superfluid phase and the Mott insulator phase are found,as well as interesting phase transitions,such as the continuous or first-order phase transition from the trimer superfluid phase to the Mott insulator phase.Our results are helpful in realizing this novel off-site trimer superfluid phase by cold atom experiments. 展开更多
关键词 Bose-Hubbard model off-site trimer superfluid density matrix renormalization group method
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The Ground and Excitation Levels of the Trimer
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作者 You Pu(Department of Physics, Wuhan University, Wuhan 430072,China) 《Wuhan University Journal of Natural Sciences》 CAS 1998年第2期163-164,共2页
The ground and excited levels of the trimer (4He)3 are obtained theoretically by solving the 2-D Faddeev integral equation in the momentum space. In solving the equation, the direct matrix inversion method (I. M.) is ... The ground and excited levels of the trimer (4He)3 are obtained theoretically by solving the 2-D Faddeev integral equation in the momentum space. In solving the equation, the direct matrix inversion method (I. M.) is used instead of the iteration and Pade approximate method. The new HFD-B Aziz potential ν is used in the calculation. 展开更多
关键词 trimer Faddeev equation matrix inversion method
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Theoretical Study on the Optical Properties for 2,7- and 3,6-Linked Carbazole Trimers by Time-dependent Density Functional Theory
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作者 王寒露 王学业 +2 位作者 王玲 王衡亮 刘爱虹 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2007年第4期413-418,共6页
Electronic properties, such as HOMO and LUMO energies, band gaps, ionization potential (IP) and electron affinity (EA) of 2,7- and 3,6-1inked carbazole trimers, two conjugated oligomcrs with different linkages of ... Electronic properties, such as HOMO and LUMO energies, band gaps, ionization potential (IP) and electron affinity (EA) of 2,7- and 3,6-1inked carbazole trimers, two conjugated oligomcrs with different linkages of carbazole, were studicd by the density functional theory with Becke-Lee-Young-Parr composite exchange correlation functional (B3LYP). The absorption spectra of these compounds were also investigated by time-dependent density functional theory (TD-DFT) with 6-3 IG* basis set. The calculated results indicated that the HOMO and LUMO of the 2,7- and 3,6-1inked carbazole trimers are both slightly destabilized on going from methyl substitution to sec-butyl substitution. Both IP and EA exhibit their good hole-transporting but poor electronaccepting ability. The presence of alkyl groups on the nitrogen atoms does not affect the intra-chain electronic delocalization along the molecular frame. Thus no significant effect on the band gap and absorption spectra of compounds has been found. 展开更多
关键词 absorption spectra carbazole trimers electronic properties time-dependent density functional theory (TD-DFT)
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Light focusing in linear arranged symmetric nanoparticle trimer on metal film system
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作者 唐裕霞 王蜀霞 +1 位作者 黄映洲 方蔚瑞 《Chinese Physics B》 SCIE EI CAS CSCD 2022年第1期540-546,共7页
Benefiting from the induced image charge on film surface,the nanoparticle aggregating on metal exhibits interesting optical properties.In this work,a linear metal nanoparticle trimer on metal film system has been inve... Benefiting from the induced image charge on film surface,the nanoparticle aggregating on metal exhibits interesting optical properties.In this work,a linear metal nanoparticle trimer on metal film system has been investigated to explore the novel optical phenomenon.Both the electric field and surface charge distributions demonstrate the light is focused on film greatly by the nanoparticles at two sides,which could be strongly modulated by the wavelength of incident light.And the influence of nanoparticle in middle on this light focusing ability has also been studied here,which is explained by the plasmon hybridization theory.Our finding about light focusing in nanoparticle aggregating on metal film not only enlarges the novel phenomenon of surface plasmon but also has great application prospect in the field of surface-enhanced spectra,surface catalysis,solar cells,water splitting,etc. 展开更多
关键词 electric field enhancement light focusing nanoparticle trimer on metal film system plasmonic hybridization
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A Fragmentation Study on Four Unusual Secoiridoid Trimers,Swerilactones H–K,by Electrospray Tandem Mass Spectrometry
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作者 Chang-An Geng Ji-Jun Chen 《Natural Products and Bioprospecting》 CAS 2016年第6期297-303,共7页
Swerilactones H–K(1–4)as four unprecedented secoiridoid trimers represent a new type of natural product,which has attracted much interest of natural chemists due to their novel skeletons and promising bioactivity.In... Swerilactones H–K(1–4)as four unprecedented secoiridoid trimers represent a new type of natural product,which has attracted much interest of natural chemists due to their novel skeletons and promising bioactivity.In order to well understand their MS fragmentation behaviors,they were investigated by electrospray ionization ion-trap time-of-flight multistage product ion mass spectrometry(ESI-IT-TOF-MSn)for the first time.The protonated molecules([M?H]?)of swerilactones J and K,and deprotonated molecules([M-H]-)of swerilactones H,J and K were readily observed in the conventional single-stage mass spectra(MS);however only the[M?Cl]-ion for swerilactone I was obtained in negative mode.Based on the MSn study,the fragmentation pathways of swerilactones H and I in negative mode,and swerilactones J and K in both positive and negative modes were proposed.The neutral losses of H_(2)O,CO,CO_(2)and C_(2)H_(4)O moieties are the particular elimination from the precursor ions due to the presence of hydroxyl,d-lactone and 1-O-ethyl moieties in their structures,of which the retro-Diels–Alder cleavage was the most particular dissociation.The fragment ions at m/z 341 and 291 in negative mode can be considered as the diagnostic ions for secoiridoid trimers.This investigation will provide valuable information for their fast characterization from complicated natural mixtures and extensive understanding their structural architectures. 展开更多
关键词 ESI-IT-TOF-MSn Fragmentation rules Secoiridoid trimers Swerilactones H-K Retro-Diels-Alder(RDA)cleavage
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Theoretical investigation of the dispersion interaction in argon dimer and trimer
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作者 Abdullah H. Quasti Walid I. Hassan 《Journal of Biophysical Chemistry》 2013年第2期91-101,共11页
The ultimate aim of the present work is to establish an acceptable level of computation for the van der waals (vdw) complexes that is able to pick up appreciable amount of dispersion interaction energy, reproduce the ... The ultimate aim of the present work is to establish an acceptable level of computation for the van der waals (vdw) complexes that is able to pick up appreciable amount of dispersion interaction energy, reproduce the equilibrium separation within the acceptable limits and at the same time cost and time effective. In order to reach this aim vdw clusters where pure isotropic dispersion interaction occur, namely, Ar dimer and trime were investigated. Computations using different basis sets and at different levels of theory have been carried out. Three basis sets, namely, the 6-31++G**, the 6-311++G** and the aug-cc-pvdz basis set, were found superior to all other basis sets used. The high performance and relative small CPU time of the 6-31++G** basis set make it a good candidate for use with large vdw clusters, especially those of interest in biology. Three compound methods were applied in the present work, namely G1, G2 and G2 Moller-Plesset (MP2) and the complete basis set method, CBS-Q. These methods failed to detect the attraction dispersion interaction in the dimer. The predicted repulsive interaction seems dominant in all these methods. Some of the recently developed Density Functional Theory (DFT) methods that were parameterized to account for the dispersion interaction were also evaluated in the present work. Results come to the conclusion that, in contrast to the claims made, state-of-the-art Density Functional Theory methods are incapable of accounting for dispersion effects in a quantitative way, although these methods predict correctly the inter-atomic separations and are?thus considered a real improvement over the conventional methods. BS-SE has been computed, analyzed and discussed. 展开更多
关键词 Vdw CLUSTERS Dispersion Interaction ARGON DIMER and trimer Ab INITIO Computation Density Functional Theory
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Synthesis,liquid crystalline and luminescent properties of trimeric phenylenevinylene with end-groups of(R)-(+)-2-methylbutyric acid ester 被引量:1
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作者 Cheng Bo Zhang Ying Li +4 位作者 Wen Ke Liu Hai Quan Zhang Huai Yang Qing Shan Li Guang Zhong Xing 《Chinese Chemical Letters》 SCIE CAS CSCD 2009年第12期1423-1426,共4页
有对称的 chiral 结束组(ChTPV ) 的 trimeric phenylenevinylene 被综合。水晶的液体和 ChTPV 的光性质被微分扫描学习了热量测定(DSC ) ,极化的光显微镜学(POM ) ,吸收和光致发光系列。结果显示 ChTPV 在一个宽温度范围和近晶的阶... 有对称的 chiral 结束组(ChTPV ) 的 trimeric phenylenevinylene 被综合。水晶的液体和 ChTPV 的光性质被微分扫描学习了热量测定(DSC ) ,极化的光显微镜学(POM ) ,吸收和光致发光系列。结果显示 ChTPV 在一个宽温度范围和近晶的阶段的一块典型光质地上展出中央阶段。在有答案的系列的对比,这部电影的出现了在最大的吸收蓝移动、在最大的排放红移动由于有 TPV 转变偶极子时刻的平行排列的 H 类型聚集。 展开更多
关键词 发光性能 三聚体 注册商标 合成 液晶 苯乙烯 光致发光光谱 差示扫描量热
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Hexafluoropropylene oxide trimer acid,a perfluorooctanoic acid alternative,induces cardiovascular toxicity in zebrafish embryos
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作者 Sujie Sun Li Zhang +8 位作者 Xue Li Lu Zang Ling Huang Junquan Zeng Zigang Cao Xinjun Liao Zilin Zhong Huiqiang Lu Jianjun Chen 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2024年第5期460-472,共13页
As an increasingly used alternative to perfluorooctanoic acid(PFOA),hexafluoropropylene oxide trimer acid(HFPO-TA)has been widely detected in global water environments.However,little is known regarding its toxic effec... As an increasingly used alternative to perfluorooctanoic acid(PFOA),hexafluoropropylene oxide trimer acid(HFPO-TA)has been widely detected in global water environments.However,little is known regarding its toxic effects on cardiovascular development.Here,zebrafish embryos were treated with egg water containing 0,60,120,or 240 mg/L HFPO-TA.Results showed that HFPO-TA treatment led to a significant reduction in both larval survival percentage and heart rate.Furthermore,HFPO-TA exposure caused severe pericardial edema and elongation of the sinus venous to bulbus arteriosus distance(SV-BA)in Tg(myl7:GFP)transgenic larvae,disrupting the expression of genes involved in heart development and thus causing abnormal heart looping.Obvious sprouting angiogenesis was observed in the 120 and 240 mg/L exposed Tg(fli:GFP)transgenic larvae.HFPO-TA treatment also impacted the mRNA levels of genes involved in the vascular endothelial growth factor(VEGF)pathway and embryonic vascular development.HFPO-TA exposure significantly decreased erythrocyte number in Tg(gata1:DsRed)transgenic embryos and influenced gene expression associated with the heme metabolism pathway.HFPO-TA also induced oxidative stress and altered the transcriptional levels of genes related to cell cycle and apoptosis,inhibiting cell proliferation while promoting apoptosis.Therefore,HFPO-TA exposure may induce abnormal development of the cardiovascular and hematopoietic systems in zebrafish embryos,suggesting it may not be a suitable or safe alternative for PFOA. 展开更多
关键词 Hexafluoropropylene oxide trimer ACID Heart development Vascular development HEMOPOIESIS Zebrafish embryos
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Novel phenanthrene/bibenzyl trimers from the tubers of Bletilla striata attenuate neuroinflammation via inhibition of NF-κB signaling pathway
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作者 SHAO Siyuan SUN Mohan +5 位作者 MA Xianjie JIANG Jianwei TIAN Jinying ZHANG Jianjun YE Fei LI Shuai 《Chinese Journal of Natural Medicines》 SCIE CAS CSCD 2024年第5期441-454,共14页
Five novel(9,10-dihydro)phenanthrene and bibenzyl trimers,as well as two previously identified biphenanthrenes and bibenzyls,were isolated from the tubers of Bletilla striata.Their structures were elucidated through c... Five novel(9,10-dihydro)phenanthrene and bibenzyl trimers,as well as two previously identified biphenanthrenes and bibenzyls,were isolated from the tubers of Bletilla striata.Their structures were elucidated through comprehensive analyses of NMR and HRESIMS spectroscopic data.The absolute configurations of these compounds were determined by calculating rotational energy barriers and comparison of experimental and calculated ECD curves.Compounds 5b and 6 exhibited inhibitory effects on LPS-induced NO production in BV-2 cells,with IC_(50) values of 12.59±0.40 and 15.59±0.83μmol·L^(-1),respectively.A mechanistic study suggested that these compounds may attenuate neuroinflammation by reducing the activation of the AKT/IκB/NF-κB signaling pathway.Additionally,compounds 3a,6,and 7 demonstrated significant PTP1B inhibitory activities,with IC_(50) values of 1.52±0.34,1.39±0.11,and 1.78±0.01μmol·L^(-1),respectively.Further investigation revealed that compound 3a might inhibit LPS-induced PTP1B overexpression and NF-κB activation,thereby mitigating the neuroinflammatory response in BV-2 cells. 展开更多
关键词 Bletilla striata Phenanthrene/bibenzyl trimer NO inhibition AKT/IκB/NF-κB signaling pathway PTP1B inhibitory effect
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