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A New Monoterpene Glycoside from Swertia punicea

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Chinese Chemical Letters 2000年第8期11卷 709-710页

作者： xin MING Ming Hua QIU Rui Lin nie Guo Lin ZHANG Kunming Institute of Botany Chinese Academy of SciencesKunming 650204 Chengdu Institute of Biology Chinese Academy of SciencesChengdu 610041

A new monoterpene glycoside, 2,6-dimethyl-2E,6E-octadienoic acid 1,6'-lactone 8-beta-D-glucopyranoside, was isolated from Swertia punicea, accompanying with six known compounds 1-O-primeverosyl-3,7-dimethoxy-8-hydroxyxanthone, 1-O-primeverosyl-3,7,8-tri-methoxyxan-thone, epi-eustomoside, 1-hydroxy-3,7,8-trimethoxyxanthone, 1,8-dihydroxy-3,7-dimethoxy xanthone and isovitexine. Their structures were elucidated based on spectral evidence.

关键词： Swertia punicea monoterpene glycoside xanthone epi-eustomoside isovitexine

Implications of diurnal variations in land surface temperature to data assimilation using MODIS LST data

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Journal of Geographical Sciences 2020年第1期30卷 18-36页

作者： FU Shiwen nie Suping LUO Yong CHEN xin Department of Earth System Science Tsinghua UniversityBeijing 100084China Numerical Weather Prediction Center China Meteorological AdministrationBeijing 100081China National Climate Center China Meteorological AdministrationBeijing 100081China

Based on the Beijing Climate Center’s land surface model BCC_AVIM(Beijing Climate Center Atmosphere-Vegetation Interaction Model),the ensemble Kalman filter(EnKF)algorithm has been used to perform an assimilation experiment on the Moderate Resolution Imaging Spectroradiometer(MODIS)land surface temperature(LST)product to study the influence of satellite LST data frequencies on surface temperature data *** assimilation results have been independently tested and evaluated by Global Land Data Assimilation System(GLDAS)LST *** results show that the assimilation scheme can effectively reduce the BCC_AVIM model simulation bias and the assimilation results reflect more reasonable spatial and temporal *** variation information in the observation data has a significant effect on the assimilation *** LST data that contain diurnal variation information can further improve the accuracy of the assimilation ***,when assimilation is performed using observation data at 6-hour intervals,a relatively good assimilation result can be obtained,indicated by smaller bias(2.2K)and RMSE(>4K).Further analysis showed that the sensitivity of assimilation effect to diurnal variations in LST varies with time and *** assimilation using observations with a time interval of 3 hours has the smallest bias in Oceania and Africa(both<1K);the use of 24-hour interval observation data for assimilation produces the smallest bias(<2.2K)in March,April and July.

关键词： land surface data assimilation land surface temperature MODIS diurnal variation

A Modeling Method for Transformer Windings Under VFTO Based on S-parameters

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高电压技术 2008年第9期34卷 1898-1904页

作者： ZHANG Ping WANG You-hua nie xin peng YAN Wei-li ZHANG Hai-jiao Electrical Department Hebei University of Technology Tianjin 300130 China Baoding Tianwei Group Baoding 071051 China

To study the Very Fast Transient Over-voltage (VFTO) distribution in transformer windings in gas insulated substation (GIS), a systematic methodology based on S-parameters is presented for establishing high-frequency model of transformer windings. Firstly, voltage transfer functions are derived from S-parameters which are calculated or measured from transformer windings. Secondly, voltage transfer functions are fitted with rational functions by the vector fitting method and then the rational transfer functions are order-reduced by optimal Pade-approximation algorithm. Lastly, the resultant voltage transfer functions are synthesized by network technology. Computational results are consistent with simulation results of Electromagnetic Transient Program (EMTP) and confirm the feasibility and validity of proposed methodology.

关键词：过电压瞬变电流变压器绕组电压转移法

Facile Synthesis of Novel Perfluorocarbon-Modulated 4-Anilinoquinazoline Analogues

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Chinese Journal of Chemistry 2017年第11期35卷 1693-1700页

作者： Huiping Shi Bonan Lai Shizhen Chen xin Zhou Jing nie Jun-An Ma Department of Chemistry Tianjin Key Laboratory of Molecular Optoelectronic Sciences Tianjin University Tianjin 300072 China Collaborative Innovation Center of Chemical Science andEngineering Tianjin 300072 China Key Laboratory of Magnetic Resonance in Biological Systems State Key Laboratory for Magnetic Resonance and Atomic and Molecular Physics National Center for Magnetic Resonance in Wuhan Wuhan Institute of Physics and Mathematics Chinese Academy of Sciences Wuhan Hubei 430071 China

4-Anilinoquinazoline analogues stand out among many kinds of small molecules that inhibit the tyrosine kinase activities of epidermal growth factor receptor （EGFR）, thus serving as significant molecular targets for anticancer drug design. Herein, a series of novel perfluorocarbon （PFC） modulated 4-anilinoquinazolines were designed and prepared straightforwardly by nucleophilic substitution reaction of various anilinoquinazolines and PFC-derived methanesulfonate. In the presence of base, the reaction proceeded smoothly to afford a wide range of 4-anilino- quinazolines with different substituents on aniline moiety in good to high yields. Furthermore, the PFC-modified analogues of gefitinib and erlotinib were also obtained in 93% and 90% respectively, which may have potential for developing new inhibitors of the epidermal growth factor receptor （EGFR） tyrosine kinase and fluorinated contrast agents （CA） for 19F MRI.

关键词： 4-anilinoquinazolines perfluorocarbon (PFC) nucleophilic substitution reaction synthesis epidermalgrowth factor receptor (EGFR)

Spatial characteristics and capacity investigation of indoor hotspot channel based on wideband MIMO measurement at 4.9 GHz

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The Journal of China Universities of Posts and Telecommunications 2010年第3期17卷 38-44页

作者： nie xin ZHANG Jian-hua HUANG Chen LIU Ze-min ZHANG Ping Key Laboratory of Universal Wireless Communications Ministry of Education Beijing University of Posts and Telecommunications Beijing 100876 China Wireless Technology Innovation Institute Beijing University of Posts and Telecommunications Beijing 100876 China

In this article, results obtained from wideband multiple-input multiple-output channel measurements at 4.9 GHz are presented. Measurements were performed in an indoor hotspot scenario with both line-of-sight and non-line-of-sight propagation conditions. Vertical polarized uniform linear arrays （ULAs） with different antenna spacing and orientation were utilized for investigating the impact of antenna configurations on the system performance. Based on measured channel impulse responses, the spatial correlation of ULA is analyzed and compared with the theoretical values calculated from the power azimuth spectrum. Following that, the eigenvalue statistics and capacity with respect to antenna spacing and orientation are given and compared. The diversity-multiplexing tradeoff （DMT） of measured channels at operational signal-to-noise ratio （SNR） is also presented. The reason why the DMT of measured channels is much lower than that ofi.i.d. Rayleigh channels is specified.

关键词： wideband multiple-input multiple-output (MIMO) measurement indoor hotspot scenario spatial characteristics capacity

Capacity evaluation of the backhaul link in the outdoor relay system at 2.35GHz

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High Technology Letters 2012年第4期18卷 401-405页

作者：张建华 Zhang Fenghua nie xin Huang Chengxiang Key Laboratory of Universal Wireless Communications Ministry of Education Beijing 100876 P. R. China Wireless Technology Innovation Institute Beijing University of Posts and Telecommunications Beijing 100876 P. R. China

A measurement campaign has been conducted at 2.35 GHz with a bandwidth of 50 MHz to ob- tain the statistics and evaluate the capacity of the backhaul link. Based on the measured channel im- pulse response, the channel gain, the eigenvalue statistics and the capacity are investigated. The distribution and corresponding parameters for describing the eigenvalue dispersion, the maximum and minimum eigenvalues are given. It is found that the backhaul link is relatively stable, which shows small variance of the channel gain. In spite of the fact that there are not many scatterers in the backhaul link, the channel rank can be enhanced by using dual-polarized antennas. Thus, the backhaul link can provide enough capacity.

关键词： relay channel measurement wideband MIMO channel channel gain eigenvaluestatistics capacity

Role of hsa_circ_0007482 in pterygium development: insights into proliferation, apoptosis, and clinical correlations

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International Journal of Ophthalmology(English edition) 2024年第8期17卷 1387-1395页

作者： Li-Yun Zhang xin Liu Shuo zheng Wen-Qun Xi Xue-Ping Wu Dan-Yao nie Hui-Ling Hu Jian-Tao Wang xin-Hua Liu Jing Zhang Shenzhen Eye Hospital Jinan UniversityShenzhen Eye InstituteShenzhen 518000Guangdong ProvinceChina

AIM:To investigate the impact of hsa_circ_0007482 on the proliferation and apoptosis of human pterygium fibroblasts(HPFs)and its correlation with the severity grades of ***:Pterygium and normal conjunctival tissues were collected from the superior area of the same patient’s eye(n=33).The correlation between pterygium severity and hsa_circ_0007482 expression using quantitative reversetranscription polymerase chain reaction(RT-qPCR)were *** distinct siRNA sequences targeting hsa_circ_0007482,along with a negative control sequence,were transfected into *** proliferation was assessed using the cell counting *** levels of Ki67,proliferating cell nuclear antigen(PCNA),Cyclin D1,Bax,B-cell lymphoma-2(Bcl-2),and Caspase-3 were measured via *** staining was employed to detect Ki67 and vimentin *** was evaluated using flow ***:Hsa_circ_0007482 expression was significantly higher in pterygium tissues compared to normal conjunctival tissues(P<0.001).Positive correlations were observed between hsa_circ_0007482 expression and pterygium severity,thickness,and vascular *** of hsa_circ_0007482 inhibited cell proliferation,reducing the mRNA expression of Ki67,PCNA,and Cyclin D1 in ***_circ_0007482 knockdown induced apoptosis,increasing mRNA expression levels of Bax and Caspase-3,while decreasing Bcl-2 expression in ***,hsa_circ_0007482 knockdown attenuated vimentin expression in ***:The downregulation of hsa_circ_0007482 effectively hampers cell proliferation and triggers apoptosis in *** are discernible positive correlations detected between the expression of hsa_circ_0007482 and the severity of pterygium.

关键词： hsa_circ_0007482 circular RNA pterygium cell proliferation apoptosis

Fe doped g-C_(3)N_(4) composited ZnIn_(2)S_(4) promoting Cr(Ⅵ) photoreduction

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Chinese Chemical Letters 2023年第4期34卷 430-435页

作者： Zhuoga Cirena Yu nie Yanfang Li Huilin Hu Xiang Huang xin Tan Tao Yu School of Environmental Science and Engineering Tianjin UniversityTianjin 300350China School of Chemical Engineering and Technology Tianjin UniversityTianjin 300350China School of Materials Science and Engineering Tianjin UniversityTianjin 300350China School of Science Tibet UniversityLhasa 850000Chin

30% Fe CN/ZIS(30% Fe doped g-C_(3)N_(4)composited ZnIn_(2)S_(4)) was synthesized by a simple water bath method, via in-situ growth of abundant well-dispersed ZnIn_(2)S_(4)nanosheets on the Fe doped g-C_(3)N_(4)surface. Experimental results showed the optimized 30% Fe CN/ZIS achieved the best photoreduction of Cr(VI)performance within a wide p H range, which was 9.5 times and 700 times higher than that of pure ZnIn_(2)S_(4)and 30% Fe CN(Fe doped g-C_(3)N_(4)). This is due to the intense synergy between the Fe-Nxbond and close interface contact produces a high-speed charge transfer channel, thus significantly improving the efficiency of optical carrier separation and migration. Meanwhile, UV-vis diffuse reflection spectra and photoluminescence spectroscopy showed that iron doping significantly narrowed the bandgap of gC_(3)N_(4), preventing electron-hole pair recombination. Further, the microstructures and charge separation properties were analyzed by scanning electron microscope, Photoluminescence Spectroscopy and timeresolved photoluminescence, which revealed the structure-activity relationship of composite structure and the synergistic mechanism of each functional component. This research should provide a viable technique for creating composites with high photocatalytic activity for the treatment of chromium-containing wastewater.

关键词： Hexavalent chromium 30%FeCN/ZIS composites Interfacial interaction Synergistic effect

Soil Characteristics Overwhelm Cultivar Effects on the Structure and Assembly of Root-Associated Microbiomes of Modern Maize

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Pedosphere 2019年第3期29卷 360-373页

作者： CHEN Lin xin Xiuli ZHANG Jiabao Marc REDMILE-GORDON nie Guangsen WANG Qingyun State Key Laboratory of Soil and Sustainable Agriculture Institute of Soil Science Chinese Academy of Sciences Nanjing 210008 (China) Department of Sustainable Soils and Grassland Systems Rothamsted Research Harpenden Herts AL5 2JQ (UK) School of Resources and Environment Anhui Agricultural University Hefei 230036 (China)

Modern breeding primarily targets crop yield traits and is likely to influence root-associated microbiomes, which play significant roles in plant growth and health. The relative importance of soil and cultivar factors in shaping root-associated microbiomes of modern maize (Zea mays L.) remains uncertain. We conducted a pot experiment in a controlled environment using three soils (Mollisol, Inceptisol, and Ultisol) and four contrasting cultivars, Denghai 605, Nonghua 816, Qiaoyu 8, and zhengdan 958, which are widely planted in China. We used 16S rRNA gene amplicon sequencing to characterize the bacterial communities in the bulk soil, rhizosphere, and endosphere. Our results showed that the four cultivars had different shoot biomass and root exudate total organic carbon and organic acid contents. The microbiomes in the bulk soil, rhizosphere, and endosphere were different. We observed apparent community divergence between soils rather than cultivars, within which edaphic factors substantially contributed to microbiome variation. Moreover, permutational multivariate analysis of variance corroborated significant contributions of soil type but not cultivar on the root-associated microbiome structure. Differential abundance analysis confirmed that each soil presented a distinct root microbiome, while network analysis indicated different co-occurrence patterns of the root microbiome among the three soils. The core root microbiome members are implicated in plant growth promotion and nutrient acquisition in the roots. In conclusion, root-associated microbiomes of modern maize are much more controlled by soil characteristics than by cultivar root exudation. Our study is anticipated to help improve breeding strategies through integrative interactions of soils, cultivars, and their associated microbiomes.

关键词： amplicon sequencing edaphic properties endosphere indigenous microbes rhizosphere root exudation