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Decarboxylative cyanation and thiocyanation via catalytic electron donor-acceptor complex with copper catalysis

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Science China Chemistry 2024年第9期67卷 3019-3028页

作者： hongping Zhao Xiaoxiang Xi Tianbao Wu Zimin chen Minyan Wang Weiming Yuan Key Laboratory of Material Chemistry for Energy Conversion and Storage Ministry of Education Hubei Key Laboratory of Bioinorganic Chemistry and Materia Medica School of Chemistry and Chemical Engineering Huazhong University of Science and Technology (HUST) State Key Laboratory of Coordination Chemistry School of Chemistry and Chemical Engineering Nanjing University Shenzhen Huazhong University of Science and Technology Research Institute

A new catalytic decarboxylative cyanation and thiocyanation via a synergistic Na I/Cu catalysis is developed. The photoexcited electron donor-acceptor complex by assembly of Na I, R3P, and N-acyloxy-phthalimide ester(NHPI ester) triggers the generation of alkyl radical species, which then engages in Cu-catalyzed radical coupling process. Key to success of this dual catalytic transformation is the reliable charge transfer between I· and Cu(I). This dual catalytic platform can eliminate the use of expensive iridium-based photocatalyst or synthetically elaborate organic dyes. A series of primary, secondary, and tertiary alkyl nitriles and thiocyanates are easily synthesized. Moreover, an asymmetric decarboxylative cyanation by applying a chiral Cu catalyst is also developed to afford chiral nitriles in high enantioselectivity. The mechanistic details and the origin of the high enantioselectivity are further investigated by the mechanistic experiments and the density functional theory calculations.

关键词： electron donor-acceptor catalysis copper catalysis cyanation thiocyanation asymmetric synthesis

Building Extraction from High Resolution SAR Imagery in Urban Areas

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Geo-Spatial Information Science 2011年第3期14卷 164-168页

作者： DONG Yansheng chen hongping YU Deyong PAN Yanzhong ZHANG Jingshui Beijing Research Center for Information Technology in Agriculture No. 11 Middle Shuguanghuayuan Road Haidian Dis- trict Beijing 100097 China Key Laboratory of Regional Climate-Environment Research for Temperate East Asia Institute of Atmosphere Physics Chinese Academy of Sciences Beijing 100029China State Key Laboratory of Earth Surface Processes and Resource Ecology Beijing Normal University No. 19 Xinjiekouwai St. Haidian District Beijing 100875 China

In this paper,the textural characteristics of the buildings were quantified by using two texture descriptors,namely,Square Root Pair Difference(SRPD) ***,a novel method,based on SRPD and,to extract building areas in ur-ban areas from very high resolution SAR images is *** results showed that this method has the ability to differentiate buildings from the complicated features in urban areas,which can be employed for land mapping and provides support for relief operations.

关键词：大楼察觉高分辨率的 SAR 质地城市的遥感

Identification and Characterization of Drought Stress-Responsive Novel microRNAs in Dongxiang Wild Rice

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Rice science 2018年第4期25卷 175-184页

作者： ZHANG Fantao LUO Yuan ZHANG Meng ZHOU Yi chen hongping HU Biaolin XIE Jiankun College of Life Sciences Jiangxi Normal University Rice Research Institute Jiangxi Academy of Agricultural Sciences

MicroRNAs （miRNAs） are non-coding small RNAs, which play important regulatory roles in response to biotic and abiotic stresses. Dongxiang wild rice （Oryza rufipogon, DXWR） can survive in extreme drought environment, but its molecular mechanism of drought resistance is still largely unknown. To further explore miRNA regulatory mechanisms involved in drought resistance, we identified 138 novel miRNAs in DXWR using small RNA sequencing and bioinformatics approaches, and found that the expression levels of 67 novel miRNAs were significantly affected by drought stress. In total, 200 candidate target genes were predicted and annotated for the drought stress-responsive novel miRNAs. Gene Ontology （GO） analysis and Kyoto Encyclopedia of Genes and Genomes （KEGG） pathways suggested that most of the target genes were related to metabolism. Stem-loop quantitative real-time PCR （qRT-PCR） results exhibited high concordance with sequencing data, which confirmed that miRNA expression patterns based on small RNA sequencing in the present study were reliable. Meanwhile, qRT-PCR validated the inverse expression patterns between several miRNAs and their target genes. These results will enhance our understanding of miRNA regulatory mechanisms in response to drought stress in DXWR, and can serve as an important reference for the protection and utilization of this valuable genetic resource.

关键词： Dongxiang wild rice drought stress genetic resource novel microRNA small RNA sequencing

Aryl C–H iodination: are there actual flavin-dependent iodinases in nature?

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Science China Chemistry 2021年第10期64卷 1730-1735页

作者： Yuyang Zhang Lin chen hongping chen Tingting Huang Qing Shi Xiaozheng Wang Yan Wang Man-cheng Tang Ning-Yi Zhou Shuangjun Lin Synthetic Biology Engineering Lab of Henan Province School of Life Science and BiotechnologyXinxiang Medical UniversityXinxiang 453003China State Key Laboratory of Microbial Metabolism Joint International Laboratory on Metabolic&Developmental SciencesSchool of Life Sciences&BiotechnologyShanghai Jiao Tong UniversityShanghai 200240China

Flavin-dependent halogenases (FDHs) are well known to introduce carbon halide bonds (mainly C–Cl and C–Br) into natural products with the assistance of a partner protein flavin reductase to generate reduced flavin (FADH_(2)or FMNH_(2)).Compared with the common chloride-and bromide-containing natural products (approximately 5,000 compounds),iodinated natural products(approximately 100 compounds) are very *** iodinases have also rarely been identified in nature to *** study discovered a novel relationship between iodination and flavin reductases for the first *** mechanistic studies,it was identified that peroxide (H_(2)O_(2)) was released from the uncoupling reaction of flavin reductases and then reacted with iodide ions(I^(-)) to produce hypoiodous acid (IOH) for the final ***,this study also unintentionally verified that the recently reported flavin-dependent iodinase Vir X1 from the marine virus and its two homologs (MBG and NCV) did not catalyze iodination in the in vitro biochemical system but likely belonged to a new phylogenetic clade in the tryptophan halogenase *** a consequence,actual flavin-dependent iodinases in nature remain to be discovered by the scientific community in the future.

关键词： flavin-dependent halogenase flavin reductase iodination H_(2)O_(2) iodinase

The reservoir forming characteristics and exploration direction of the condensate gas reservoir in Hailar Basin

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Acta Geologica Sinica(English Edition) 2015年第A1期89卷 363-366页

作者： WU Haibo LI Junhui chen hongping Daqing Oil Field Co exploration and Development Research Institute

Gas condensate is a special oil and gas resource, and it is a hot spot for geologists and geologists in recent years.. When gas condensate oil content is equal to or greater than 50g/m3, gasoline generally greater tha... 详细信息

关键词： GAS condensate reservoirs GAS fields COAL NATURAL gas -- Prospecting GEOLOGY

Estimation of Octanol-Water Partition Coefficient of Chloride Hydrocarbon by Group Contribution Method

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Chinese Journal of Chemical Engineering 2007年第5期15卷 715-719页

作者：梁英华陈红萍 College of Chemical Engineering and Biological Technical Hebei Polytechnic University Tangshan 063009 China

为氯化物烃的 octanol 水分区系数(Kow ) 的评价的命名的二水平的组贡献(GC-K ) 方法被介绍的一个新奇方法。方程包括仅仅正常的沸腾的点和混合物的分子的重量。为 Kow 的 12 个第一水平的组和 7 个秒级的组的组贡献参数被三种类型的相... 详细信息

为氯化物烃的 octanol 水分区系数(Kow ) 的评价的命名的二水平的组贡献(GC-K ) 方法被介绍的一个新奇方法。方程包括仅仅正常的沸腾的点和混合物的分子的重量。为 Kow 的 12 个第一水平的组和 7 个秒级的组的组贡献参数被三种类型的相关试验性的数据包括 57 混合物获得。由比较，评价结果与第一水平二水平的组，后者与最近的修正的增加更好，这被观察，这完成。什么时候与 Marrero 的三水平的组贡献途径和原子碎片贡献方法(声频抗流圈) 相比，由第一水平的组的 GC-K 的平均相对错误的精确性是 7.20% 并且被喜欢而不是另外的方法。

关键词：基团贡献法氯代化合物正辛醇-水分配系数

Spectral　Changes　of　Partially　Coherent　Light　Transmitted　from　a　Dielectric　Slab

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Chinese Journal of Lasers 1995年第5期B4卷 439-446页

作者： chen hongping LIN Qiang LU Xuanhui WANG Shaomin (Department of Physics,Hangzhou University, Hangzhou 310028, China) Hangzhou Univ Hangzhou China

ＳｐｅｃｔｒａｌＣｈａｎｇｅｓｏｆＰａｒｔｉａｌｌｙＣｏｈｅｒｅｎｔＬｉｇｈｔＴｒａｎｓｍｉｔｔｅｄｆｒｏｍａＤｉｅｌｅｃｔｒｉｃＳｌａｂＣＨＥＮＨｏｎｇｐｉｎｇ；ＬＩＮＱｉａｎｇ；ＬＵＸｕａｎｈｕｉ；ＷＡＮＧＳｈａ... 详细信息

ＳｐｅｃｔｒａｌＣｈａｎｇｅｓｏｆＰａｒｔｉａｌｌｙＣｏｈｅｒｅｎｔＬｉｇｈｔＴｒａｎｓｍｉｔｔｅｄｆｒｏｍａＤｉｅｌｅｃｔｒｉｃＳｌａｂＣＨＥＮＨｏｎｇｐｉｎｇ；ＬＩＮＱｉａｎｇ；ＬＵＸｕａｎｈｕｉ；ＷＡＮＧＳｈａｏｍｉｎ（Ｄｅｐａｒｔｍｅｎｔｏｆ...

关键词： partially coherent light transmitted spectrum spectral shift

Systematic Characterization of Long Non-Coding RNAs and Their Responses to Drought Stress in Dongxiang Wild Rice

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Rice science 2020年第1期27卷 21-31页

作者： QI Weidong chen hongping YANG Zuozhen HU Biaolin LUO Xiangdong AI Bing LUO Yuan HUANG Yu XIE Jiankun ZHANG Fantao College of Life Sciences Jiangxi Normal UniversityNanchang 330022China Rice Research Institute Jiangxi Academy of Agricultural SciencesNanchang 330200China Cipher Gene Limited Liability Company Beijing 100080China

Long non-coding RNAs(lncRNAs) play important roles in response to various biotic and abiotic stresses. So far, systematic identification and characterization of lncRNAs have been reported in a few model plant species and major crops, but their roles in abiotic stress response have not yet been reported in common wild rice(Oryza rufipogon). Dongxiang wild rice(DXWR) possesses a high degree of drought resistance and has been well recognized as a precious genetic resource for drought resistant rice breeding. We presented the reference catalog of 1 655 novel lncRNA transcripts in DXWR using strand-specific RNA sequencing and bioinformatics approaches. Meanwhile, a total of 1092 lncRNAs were determined as differentially expressed lncRNAs under drought stress. Quantitative real-time PCR results exhibited a high concordance with RNA sequencing data, which confirmed that the expression patterns of lncRNAs based on RNA sequencing were highly reliable. Furthermore, 8 711 transcripts were predicted as target genes of the differentially expressed lncRNAs. Functional annotation analysis based on Gene Ontology and Kyoto Encyclopedia of Genes and Genomes databases showed that the target genes were significantly enriched in cellular and metabolic processes, cell part, binding and plant hormone signal transduction, as well as many other terms related to abiotic stress resistance. These results expanded our understanding of lncRNA biology and provided candidate regulators for genetic improvement of drought resistance in rice cultivars.

关键词： Dongxiang wild rice drought stress long non-coding RNA systematic characterization

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不同年份标准仓储广陈皮表面微生物的分布

中国食品学报 2022年第3期22卷 281-287页

作者：陈林吴蓓陈鸿平王福胡媛刘友平成都中医药大学药学院中药标准化教育部重点实验室西部特色中药资源——省部共建国家重点实验室成都611137

目的:研究不同年份标准仓储广陈皮表面微生物的分布特点。方法:采用高通量测序的方法对贮存年限为0,1,2,3,4,5,10,15,30年的广陈皮进行测序,结合OUT分析、Alpha多样性分析与主成分分析方法,分析广陈皮表面真菌与细菌在“属”水平的分布... 详细信息

目的:研究不同年份标准仓储广陈皮表面微生物的分布特点。方法:采用高通量测序的方法对贮存年限为0,1,2,3,4,5,10,15,30年的广陈皮进行测序,结合OUT分析、Alpha多样性分析与主成分分析方法,分析广陈皮表面真菌与细菌在“属”水平的分布特点。结果:9个贮存年限的广陈皮样品中真菌的物种类型丰富程度总体为先上升后下降,在贮存年限为2,3,4,5,10年时,物种类型数目较多且均一性好。前10年的优势菌属主要为青霉菌属与曲霉属,而后是耐干霉菌属。有别于真菌,细菌种类数目的变化波动较大,但每种细菌的丰度变化幅度较小。优势细菌属有鞘氨醇单胞菌属、乳杆菌属、另枝菌属与泛菌属,分别为贮存年限0,1,2,4年样品的优势菌属,以及在各年份样品中均占有较高相对丰度的瘤胃球菌属。结论:根据不同年份菌属分布特点,建立了以真菌特征菌属为主,细菌特征菌属为辅的模式,可用于初步判断广陈皮药材的贮存时间。

关键词：标准仓储广陈皮细菌真菌特征菌属