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Preparation and spectral characteristics of anthracene/tetracene mixed crystals

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Science China Chemistry 2009年第2期52卷 181-187页

作者： LI HuiPing DUAN lian.ZHANG DeQiang DONG GuiFang WANG LiDuo QIU Yong Key Lab of Organic Optoelectronics&Molecular Engineering of Ministry of Education Department of ChemistryTsinghua Univer-sityBeijing 100084China

A series of tetracene-doped anthracene crystals with different doping concentrations(the highest mo-lar ratio 100:1) are grown from *** structures and optical characteristics of the above mixed crystals are investigated at room *** changing the doping concentrations,the fluorescence can be adjusted from blue-green to green and even to *** emission spectra of anthracene/tetracene(An/Te) mixed crystals reveal the sensitized fluorescence of tetracene and the partial quenching of anthracene *** data of transient photoluminescence(PL) decays illus-trate that in An/Te mixed crystals,the decay of anthracene becomes faster,while the PL lifetime of tet-racene is longer than that of the tetracene single *** above experimental results suggest that there is excitation energy transfer from anthracene to tetracene in the mixed crystals.

关键词： anthracene tetracene organic mixed crystals fluorescence spectrum energy transfer

Preparation of Highly Active Pt-K/γ-Al_2O_3 Catalyst for o-Phenylphenol Synthesis from o-Cyclohexenyl-cyclohexanone Dehydrogenation

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Chemical Research in Chinese Universities 2008年第6期24卷 726-730页

作者： DING Jie-lian.LIN Ling XU Jian-dong ZENG Chong-yu College of Chemistry and Chemical Engineering Nanjing University of Technology Nanjing 210009 P R. China

0.5%Pt-K/γ-Al2O3 catalysts for the synthesis of o-phenylphenol（OPP） from o-cyclohexenyl-cyclohexanone （dimer） dehydrogenation were prepared by means of a two subsequent impregnation method. The effects of catalyst preparation parameters, such as K promoters, calcination, and reduction conditions, were investigated. The results showed that the addition of K2SO4 to Pt/γ-Al2O3 catalyst notably promoted the selectivity of OPP, and its optimum content was found to be 6% in mass fraction. The higher activity was obtained when Pt/γ-Al2O3 catalyst was calcined in nitrogen atmosphere at 400--500 ℃ and then reduced at the same temperature for 3 h in hydrogen atmosphere. The conversion of the dimer and the selectivity of OPP were always above 99% and 90%, respectively, over 0.5%Pt-6% K2SO4/γ-Al2O3 catalyst during the pilot scale test of 8000 h.

关键词： o-Phenylphenol Pt catalyst K promoters Calcinations Reduction

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融合NFFD与图卷积的单视图三维物体重建

光学精密工程 2022年第10期30卷 1189-1202页

作者：连远锋裴守爽胡伟中国石油大学(北京)计算机科学与技术系北京102249 石油数据挖掘北京市重点实验室北京102249

为了解决复杂拓扑结构及非规则表面细节缺失等导致的单视图三维物体重建结果不准确问题,本文提出了一种融合非均匀有理B样条自由形变(NFFD)与图卷积神经网络的三维物体重建方法。首先,通过引入连接权重策略的控制点生成网络对2D视图进... 详细信息

为了解决复杂拓扑结构及非规则表面细节缺失等导致的单视图三维物体重建结果不准确问题,本文提出了一种融合非均匀有理B样条自由形变(NFFD)与图卷积神经网络的三维物体重建方法。首先,通过引入连接权重策略的控制点生成网络对2D视图进行特征学习,获得其控制点拓扑结构。然后,利用NURBS基函数对控制点坐标自适应特性建立点云模型轮廓间顶点的形变关系。最后,为增强细节信息,将混合注意力模块嵌入图卷积网络对形变后的点云位置进行调整,从而实现复杂拓扑结构和非规则表面的高效重建。在ShapeNet数据集的实验表明,CD指标平均值为3.79,EMD指标平均值为3.94,并在Pix3D真实场景数据集上取得较好重建效果。与已有的单视图点云三维重建方法比较,本文方法有效地提高了重建精度,具有较强的鲁棒性。

关键词： NURBS自由形变三维重建图卷积网络混合注意力控制点生成网络

Cinnamate-functionalized hyperbranched polymer as liquid crystal photo-alignment layer

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Chinese Chemical Letters 2008年第9期19卷 1131-1134页

作者： Bin Jun Shen Zheng Xie Ya Ning He Yan Qing lian Institute of Polymer Research Department of Chemical Engineering Laboratory of Advanced Materials Tsinghua University Beijing 100084 China

In this work, 4-methoxylcinnamoyl chloride was reacted with a commercial hyperbranched polymer （Boltom-TM H30） to prepare a hyperbranched photosensitive polymer （H30-Ci）. The polymer was characterized by UV absorption spectrum and 1H- NMR spectrum. After processed by Linearly Polarized Polymerization （LPP） method, the spin-coated films of H30-Ci were used as photo-alignment layers to assemble liquid crystal （LC） cells containing nematic liquid crystal （5CB）. The observation by polarized microscope showed that the H30-Ci blended with a linear polymer （BP-AN-Ci） photo-alignment layers could align LC molecules in a very uniform way.

关键词： Hyperbranched polymer Photo-alignment layer Linearly polarized polymerization (LPP) Liquid crystal display

Up-regulation of the transient A-type K^＋ current （IA） in the differentiation of neural stem cells of the early postnatal rat hippocampus

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Chinese Medical Journal 2010年第13期123卷 1731-1735页

作者： GUO Hong-bo huan. lian.yan ZOU Yu-xi ZOU Fei Department of Neurosurgery Guangdong Neurosurgery Institute and Key Laboratory on Brain Repair and Regeneration Zhujiang Hospital Southern Medical University Guangzhou Guangdong 510282 China School of Public Health and Tropical Medicine Southern Medical University Guangzhou Guangdong 510515 China

Background Neural stem cells （NSCs） not only are essential to cell replacement therapy and transplantation in clinical settings, but also provide a unique model for the research into neurogenesis and epigenesis. However, little attention has been paid to the electrophysiological characterization of NSC development. This work aimed to identify whether the morphological neuronal differentiation process in NSCs included changes in the electrophysiological properties of transient A-type K^＋ currents （IA）. Methods NSCs were isolated from early postnatal rat hippocampus and were multiplied in basic serum-free medium containing basic fibroblast growth factor. Potassium currents were investigated and compared using whole-cell patch-clamp techniques and one-way analysis of variance （ANOVA）, respectively. Results Compared with NSC-derived neurons, cloned NSCs （cNSCs） had a more positive resting membrane potential, a higher input resistance, and a lower membrane capacitance. Part of cNSCs and NSC-derived neurons possessed both delayed-rectifier K^＋ currents （IDR） and IA, steady-state activation of IA in cNSCs （half-maximal activation at （21.34=L-4.37） mV） occurred at a more positive voltage than in NSC-derived neurons at 1-6 days in vitro （half-maximal activation at （12.85=L-4.19） mV）. Conclusions Our research revealed a developmental up-regulation of the IA component during differentiation of postnatal NSCs. Together with the marked developmental up-regulation of IDR in vitro neuronal differentiation we have previously found, the voltage-gated potassium channels may participate in neuronal maturation process.

关键词： stem cells transient A-type K^+ currents cell differentiation hippocampus patch-clamp techniques

Distinguishing ectomycorrhizal and saprophytic fungi using carbon and nitrogen isotopic compositions

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Geoscience Frontiers 2012年第3期3卷 351-356页

作者： Weiguo Hou Bin lian.Hailian. Dong Hongchen Jiang Xinglian. Wu State Key Laboratory of Biogeology and Environmental Geology China University of Geosciences Beijing 100083 China State Key Laboratory of Environmental Geochemistry Institute of Geochemistry Chinese Academy of Sciences Guiyang 550002 China Department of Geology and Environmental Earth Science Miami University Oxford OH 45056 USA Guizhou Academy of Sciences Guiyang 550001 China

Ectomycorrhizal fungi, a group of widespread symbiotic fungi with plant, obtain carbon source from trees and improve plant mineral nutrient uptake with their widespread hyphal network. Ectomycorrhizal fungi can be used as inoculants to improve the survival rates of plantation. Saprophytic fungi use the nutrition from the debris of plant or animals, and it is difficult to distinguish the saprophytic and ectomycorrhizal fungi by morphological and anatomic methods. In this research, the differences of stable carbon and nitrogen isotopic compositions of these fungi were analyzed. The results showed that the abundances of 13C of were higher than those of ectomycorrhizal fungi and the abundances of 15N of saprophytic fungi were lower than those of ectomycorrhizal fungi. Such differences of stable carbon and nitrogen isotopic compositions between ectomycorrhizal fungi and saprophytic fungi can be ascribed to their different nutrition sources and ecological functions. These results collectively indicate that stable carbon and nitrogen isotopic compositions are an effective proxy for distinguishing between ectomycorrhizal and saprophytic fungi.

关键词： Ectomycorrhizal fungi Saprophytic fungi Stable isotopiccompositions Ecological function

Novel insights into the effect of Xiaoyao san on corticosterone-induced hepatic steatosis:inhibition of glucocorticoid receptor/perilipin-2 signaling pathway

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Acupuncture and Herbal Medicine 2022年第1期2卷 49-57页

作者： lian.Gong Guo-En Wang Qing-Yu Ma Wen-Zhi Hao Min-Hua Xian Yan-Ping Wu Hiroshi Kurihara Rong-Rong He Jia-Xu Chen Formula-Pattern Research Center School of Chinese MedicineJinan UniversityGuangzhouChina Guangdong Engineering Research Center of Chinese Medicine&Disease Susceptibility Jinan UniversityGuangzhouChina School of Traditional Chinese Medicine Guangdong Pharmaceutical UniversityGuangzhouChina

Objective:Xiaoyao san(XYS)is a classic traditional Chinese medicinal *** has been clinically administered to regulate liver ***,its mechanisms in glucocorticoid-induced hepatic steatosis are *** study aimed to investigate whether XYS protects against corticosterone(CORT)-induced hepatic steatosis,and to explore its ***:High-fat diet mice induced with hepatic steatosis by 2mg/kg CORT were administered 2.56 g/kg or 5.12 g/kg XYS daily for 7 *** effects of XYS on hepatic steatosis in mice were evaluated by H&E and Oil Red O staining and by measuring their plasma lipids(triglyceride,total cholesterol,and free fatty acids).The mechanism of XYS against hepatic steatosis was investigated by network pharmacology,immunohistochemistry,western blotting,and gain-of-function/loss-offunction ***:XYS alleviated CORT-induced steatosis,decreased plasma lipids,and inhibited glucocorticoid receptor(GR)activation in the *** pharmacology data indicated that XYS may have mitigated hepatic steatosis via GR which mediated adipose differentiation-related protein(ADFP).Gain-of-function/loss-of-function experiments in vitro confirmed that GR positively regulated ADFP ***:XYS ameliorated CORT-induced hepatic steatosis by downregulating the GR/ADFP axis and inhibiting lipid *** studies implicate that XYS is promising as a therapy for CORT-induced hepatic steatosis,and lay the foundation for designing novel prophylactic and therapeutic strategies on CORT-induced hepatic steatosis.

关键词： Adipose differentiation-related protein Glucocorticoid receptor Hepatic steatosis Network pharmacology Xiaoyao san

Morphology of Kaloula rugifera and K. borealis Tadpoles(Anura: Microhylidae: Kaloula verrucosa Group) in China

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Asian Herpetological Research 2011年第3期2卷 169-175页

作者： Bing ZHOU Pipeng LI Yuyan LU Jing lian.Zhengyan ZHOU Institute of Applied Ecology Chinese Academy of Sciences Graduate University of Chinese Academy of Sciences Institute of Herpetology and Liaoning Key Lab of Evolution and Biodiversity Shenyang Normal University

The external morphology and internal oral features of the tadpoles of Kaloula rugifera and K. borealis are described in this paper. Similarities between these two larvae include external morphology, oral disc, internal oral features(floor and roof), terminal mouth, lateral eyes, single midventral spiracle, absence of keratinized jaw sheaths and labial teeth, absence of lingual papillae and postnarial arena, while the body of K. rugifera is bigger than that of K. borealis at stages from 36 to 39 and the number of papillae in the buccal cavity is 12–19 and 9–16, respectively in the two species. All the similarities and differences of the two species illustrate that the tadpoles within the family Microhylidae could be attributed to assistance in clarifying a certain taxonomic treatment in Microhylidae.

关键词： tadpole external morphology oral disc internal oral feature taxonomy

Design, Synthesis, and Evaluation of 3-（（4-（t-Butyl）-2-（2- benzylidenehydrazinyl）thiazol-5-yl）methyl）quinolin- 2（1H）-ones as Neuraminidase Inhibitors

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Chinese Journal of Chemistry 2016年第4期34卷 403-411页

作者： Yilin Fang Mengwu Xiao Aixi Hu Jiao Ye Wenwen lian.Ailin Liu College of Chemistry and Chemical Engineering Hunan University Changsha Hunan 410082 China Institute of Materia Medica Chinese Academy of Medical Sciences & Peking Union Medical College Beifing 100050 China

A series of novel 3-（（4-（t-buty-）-2-（2-benzylidenehydrazinyl）thiazol-5-yl）methyl）quinolin-2（1H）-ones （7a--7z） were designed, synthesized and evaluated for their ability of inhibiting neuraminidase （NA） of influenza H1N1 virus. Some compounds displayed moderate influenza NA inhibitory activity. Compound 71 with the scaffold of 2-（2-（2-methoxybenzylidene）hydrazinyl）thiazole was the best one, exhibiting moderate NA inhibitory activity with ICs0 of 44.66 ~tmol/L. Structure-activity relationship showed that compounds with methoxy or hydroxy groups at the ortho position, fluorine and nitro groups at the meta position and chlorine and bromine groups at the para posi- tion of phenyl ring were more active. Docking study indicated that compound 71 has important interactions with some key residues （including Asp151, Glu119, Arg292, Tyr406, and Asn347） and binds to 430-cavity adjacent to NA active site.

关键词： neuraminidase inhibitor 3-((4-(t-butyl)-2-(2-benzylidenehydrazinyl)thiazol-5-yl)methyl)quinolin-2(1H)-ones 2-(2-hydrazinyl)thiazole scaffold synthesis docking