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Synthesis of water-soluble cystine C_(60) derivative with catalyst and its active oxygen radical scavenging ability

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Chinese Chemical Letters 2007年第1期18卷 51-54页

作者： zhen Hu Wen Chao Guan Xiang Ying Tang li zhen Huang Hong xu Department of Chemistry Huazhong University of Science and Technology Wuhan 430074 China

A novel water-soluble cystine C60 derivative was synthesized in the presence of the catalyst, tetrabutylammonium hydroxide （TBAH）. The product was characterized by FT-IR, UV, ^1H NMR, ^13C NMR, MS and elemental analysis. Furthermore, the scavenging ability to superoxygen anion radical O2^·- and hydroxyl radical ^·OH was studied by chemiluminescence. It was found that cystine C60 derivative showed an excellent efficiency in eliminating superoxygen anion radical and hydroxyl radical. The 50% inhibition concentration （IC50） for superoxygen anion radical and hydroxyl radical were 0.167 and 0.008 mg/mL, respectively.

关键词： Cystine C60 derivatives TBAH Superoxygen anion radical Hydroxyl radical Chemiluminescence

Two New Polyoxygenated Cyclohexenes from Uvaria kweichowensis

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Chinese Chemical Letters 2005年第10期16卷 1343-1346页

作者： Qiong Ming xu Zhong Mei ZOU li zhen xu Shi lin YANG Institute of Medicinal Plant Development Peking Union Medical College and Chinese Academy of Medicinal Sciences Beijing 100094

Two new polyoxygenated cyclohexenes, kweichowenol A and B were isolated from the leaves of Uvaria kweichowensis and their structures were established on the basis of their spectral data.

关键词： Annonaceae Uvaria kweichowensis leaves cyclohexenes kweichowenol A kweichowenol B.

A New Cyclohexene Oxide from Uvaria tonkinensis ***

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Chinese Chemical Letters 2003年第11期14卷 1144-1145页

作者： An liU Zhong Mei ZOU li zhen xu Shi lin YANG Institute of Medicinal Plant Development Chinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100094

A new compound, subglain B, was isolated from the stems of Uvaria tonkinensis var. subglabra and its structure was identified as 1S, 2R, 3S, 6R-1-benzoyloxymethylene-1,2- dihydroxy-3-benzoyloxy-6-chlorocyclohex-4-ene ... 详细信息

关键词： Uvaria tonkinensis var subglabra subglain B cyclohexene.

Two New Saponins from Lysimachia capillipes Hemsl.

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Journal of Integrative Plant Biology 2005年第10期47卷 1271-1275页

作者： Jing-Kui TIAN Zhong-Mei ZOU li-zhen xu Shi-lin YANG Department of Chinese Medicine Sciences and Engineering Zhejiang University Hangzhou 310027 China Institute of Medicinal Plants Development Chinese Academy of Medical Sciences and Peking Union Medical College Beijing 100094 China

To investigate the saponins from whole plants of Lysimachia capilUpes Hemsl., two new saponins, named capilliposide E （1） and capilliposide F （2）, were isolated. The structures of the new saponins were elucidated as 3β, 22α-dihydroxy-16α-acetat-28→ 13-lactone-oleanane-3-O- [β-D-glucopyranosyl- （1 →2）-α-L-arabinpyranoyl]-22-O-β-D-glucopyranoside （1） and 3β, 22α-dihydroxy- 16α-acetat-28→ 13-lactone-oleanane-3-O-{ [β-D-glucopyranosyl-（1→2）-β-D-glucopyranosyl-（1→4）]-α-L-arabinpyranoyl}-22-O-β- D-glucopyranoside （2）. The structures of these compounds were determined by 1D- and 2D-NMR, MS techniques, and chemical methods.

关键词： capilliposide E and F, Lysimachia capillipes triterpene saponin.

New Cytotoxic Saponins from Lysimachia davurica Ledeb.

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Journal of Integrative Plant Biology 2006年第2期48卷 232-235页

作者： Jing-Kui Tian Zhong-Mei Zou li-zhen xu Shi-lin Yang Department of Chinese Medicine Sciences and Engineering Zhejiang University Hangzhou 310028 China Institute of Medicinal Plants Development Chinese Academy of Medical Sciences and Peking Union Medical College Beijing 100094 China

To investigate the saponins from whole plants of Lysimachia davurica Ledeb., two new saponins named davuricoside I （compound 1） and E （compound 2） were isolated. Their chemical structures were elucidated as 3β, 16α, 28, 29-tetrihydroxy-olean-12-en-3-O-β-D-glucopyranosyl-（1→2）-β-D-glucuronopyranoside （compound 1） and 3β, 16α, 29-trihydroxy-13, 28-epoxy-oleanane-3-O-β-D-glucopyranosyl-（1→2）-β-D-glucuronopyranoside （compound 2） on the basis of their one- and two-dimensional nuclear magnetic resonance and mass spectrometry data, and chemical methods. Compound 1 showed significant cytotoxic activity against human A2780 cells.

关键词： davuricoside I and E Lysimachia davurica triterpene saponin.

High laser damage threshold coatings and damage testing technology

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光学精密工程 2005年第4期13卷 500-504页

作者： MA Ping HU Jian-ping CHEN Song-lin TANG Ming WANG zhen li Wei xu Qiao Chengdu Fine Optical Engineering Research Center Chengdu 610041China

The laser-induced damage threshold(liDT) of optical coating is a limited factor for development of a high peak power laser. The automatic damage testing facility was built to determine the liDT of optics at 1 064 nm and 355 nm.. The cleanning and processing procedure of the substrate and coating technique were improved, and the damage resistance of high-reflective coating at 1 064 nm was increased.

关键词：激光涂覆技术 liDT 自动机械光学仪器激光仪器

Two Novel Saponins from Lysimachia capillipes

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Chinese Chemical Letters 2005年第12期16卷 1607-1610页

作者： Jing Kui TIAN Chen XIE Zhong Mei ZOU li zhen xu Shi lin YANG Deptment of Chinese Medicine Science ＆ Engineering Zhejiang University Hangzhou 310028 Institute of Medicinal Plants Development Chinese Academy of Medical Sciences and Peking Union Medical College Beijing 100094

Two new saponins named capilliposide C 1 and capilliposide D 2 were isolated from the whole plants of Lysimachia capillipes, their structures were deternuned by 1D and 2D NMR, ESIMS techniques, and chemical *** C show... 详细信息

关键词： Lysimachia capillipes triterpene saponin capilliposide C and D

Design Research of a Novel Aftercool-Humidifier Concept for Humid Air Turbine Cycle

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Journal of Thermal Science 2024年第3期33卷 951-969页

作者： ZHANG Junzheng xu zhen School of Energy and Power Engineering Shandong UniversityJi’nan250061China Shandong Engineering Laboratory for High-efficiency Energy Conservation and Energy Storage Technology&Equipment Shandong UniversityJi’nan250061China

Humid air turbine cycle(HAT)has potential of electrical efficiencies comparable to combined cycle,with lower investment cost and NO_(x) *** typical heat exchanger network of HAT consists of intercooler(if there is),aftercooler,recuperator,economizer and humidifier,which brings higher efficiency but makes the system more *** simplify HAT layout,a novel humidifier concept is proposed by integrating the aftercooler into traditional counter-current *** on this concept,a one-dimensional model including pressure drop and exergy calculation is established to distinguish the thermodynamic and hydrodynamic characteristics,and then the structural parameters,such as the number of rows and columns,tube diameter,pitch and type for a micro HAT are *** results show that the aftercool-humidifier plays the same role as original aftercooler and humidifier,and can match the in-tube air,out-tube air and water stream well with lower *** the case of micro HAT cycle,the volume of heat and mass transfer area can be reduced by 47%compared with traditional *** major thermal resistance occurred in the convection heat transfer process inside the tube;however,using enhanced tube cannot effectively improve the compactness of device.

关键词： humid air turbine cycle humidifier thermodynamic analysis one-dimensional model

SG-NeRF:Sparse-Input Generalized Neural Radiance Fields for Novel View Synthesis

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Journal of Computer Science & Technology 2024年第4期39卷 785-797页

作者： Kuo xu Jie li zhen-Qiang li Yang-Jie Cao School of Cyber Science and Engineering Zhengzhou UniversityZhengzhou 450002China Intelligent Big Data System(iBDSys)Lab Shanghai Jiao Tong UniversityShanghai 200240China School of Computer and Artificial Intelligence Zhengzhou UniversityZhengzhou 450001China

Traditional neural radiance fields for rendering novel views require intensive input images and pre-scene optimization,which limits their practical *** propose a generalization method to infer scenes from input images and perform high-quality rendering without pre-scene optimization named SG-NeRF(Sparse-Input Generalized Neural Radiance Fields).Firstly,we construct an improved multi-view stereo structure based on the convolutional attention and multi-level fusion mechanism to obtain the geometric features and appearance features of the scene from the sparse input images,and then these features are aggregated by multi-head attention as the input of the neural radiance *** strategy of utilizing neural radiance fields to decode scene features instead of mapping positions and orientations enables our method to perform cross-scene training as well as inference,thus enabling neural radiance fields to generalize for novel view synthesis on unseen *** tested the generalization ability on DTU dataset,and our PSNR(peak signal-to-noise ratio)improved by 3.14 compared with the baseline method under the same input *** addition,if the scene has dense input views available,the average PSNR can be improved by 1.04 through further refinement training in a short time,and a higher quality rendering effect can be obtained.

关键词： Neural Radiance Fields(NeRF) multi-view stereo(MVS) new view synthesis(NVS)