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The Clam Cyclina sinensis (Gmelin) Phylogeography Study with 28S rRNA Gene and Potential of Nuclear rRNA Genes in Genetic Assessments of Molluscs

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Journal of Ocean University of China 2022年第2期21卷 395-399页

作者： ni gang LI Qi KONG Lingfeng YU Hong The Key Laboratory of Mariculture Ministry of EducationOcean University of ChinaQingdao 266003China Laboratory for Marine Fisheries Science and Food Production Processes Qingdao National Laboratory for Marine Science and TechnologyQingdao 266003China Laboratory of Tropical Marine Germplasm Resources and Breeding Engineering Sanya Oceanographic InstitutionOcean University of ChinaSanya 572000China

Intraspecific diversity of molluscan species is usually studied based on maternally inherited mitochondrial DNA,from which only part of the evolutionary history can be *** nuclear ribosomal RNA genes such as 28S rRNA represent poten-tial candidates that can be easily applied in phylogeography because of lacking intraindividual ***,considering their low polymorphism,genetic appraisals on whether and how they can be used in population studies are ***,we applied a short 28S rRNA to assess genetic patterns of the clam Cyclina sinensis along the coast of China and compared the results with a for-mer study based on COI and ITS-1 *** results revealed the 28S rRNA data set was characterized by an extremely low level of variation,with only seven haplotypes defined for 93 *** and nucleotide diversity for each population was al-most the lowest when compared with the other two ***,the distribution of two dominant haplotypes showed clear geo-graphic patterns,and significant population differentiation was revealed between the East China Sea and the South China *** patterns were highly concordant with findings of the former study that populations of *** were historically separated by land bridges among sea *** study suggested that although the nuclear rRNAs have shortcomings such as low variation,they have advantages including lack of intraindividual variation and high amplification *** rRNA genes can enrich the toolbox of nuclear markers in molluscan phylogeographic studies.

关键词： marine phylogeography molluscs nuclear gene genetic break

Investigation on a Small Oscillogram

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Chinese Chemical Letters 2005年第9期16卷 1249-1251页

作者： Hong Fang ZHANG Jian Bin ZHENG Hong gang ni Hung KAO Institute of Analytical Science/Shaanxi Provincial Key Lab of Electroanalytical Chemistry Northwest University Xi＇an 710069

A small oscillogram, one end of which was substituted by a bright point caused by the redox of an appropriate depolarizer and the other end of which was the redox of Hg or the redox of supporting electrolyte cation, was investigated in this paper. Experimental results of application of the small oscillogram to oscillographic determination of cefoperazone showed that the small osciUogram was more stable, sensitive, and less interference than classical oscillogram.

关键词： Electroanalysis oscillographic analysis oscillogram

Direction Finding with Cyclostationarity Analysis Against Frequency Interference

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Journal of Communications and Information Networks 2022年第1期7卷 88-95页

作者： Han Liu Jingfeng Chen Ziheng Ding gang ni Chong He Ronghong Jin Department of Electronic Engineering Shanghai Jiao Tong UniversityShanghai 200240China

In this paper, a novel anti-interference direction finding(DF)method for amplitude comparison method based on cyclostationarity is proposed. With the periodic properties of the communication signals, the desired signal’s amplitude value can be effectively obtained even though there is an interference signal whose frequency spectrum overlaps with the desired signal in the environment,and the corresponding incident angle can be estimated accurately with the amplitude comparison method. The influence of interference signal on the amplitude comparison method is discussed and the proposed method’s theoretical feasibility is also analyzed. Compared with the conventional method,simulations are provided to demonstrate the anti-interference capability of the proposed method. The amplitude comparison DF system working at 2.44 GHz and 5.8 GHz is also constructed to verify its feasibility.

关键词： cyclostationarity cyclic autocorrelation function(CAF) amplitude comparison method direction finding(DF)

Giant Hall Effect of Fe_(45.51)(Al_(2)0_(3))_(54.49)Nano-granular Film

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Chinese Physics Letters 2000年第3期17卷 227-229页

作者： XU Qing-Yu ni gang SANG Hai DU You-Wei National Laboratory of Solid State Microstructures Nanjing UniversityNanjing 210093

A series of Fe_(45.51)(Al_(2)0_(3))_(54.49)nano-granular films were prepared using ion-b€am sputtering technique.A saturated h^ll resistivity of about 12.5μΩ·cm at room temperature was *** trstnsmission electron microscopy image showed that very small Fe particles of smaller than Inm are embedded in Al_(2)0_(3)matrix,and connected into *** measured p-T curve indicated that this giant Hall effect may originate from the percolation *** different annealing temperature(TA)up to 300℃,the saturated Hall resistivity decreased only a *** good thermal stability of Fe_(45.51)(Al_(2)0_(3))_(54.49)nano-granular Films showed potential application for magnetic sensor.

关键词： technique. resistivity saturated

Recent Progress on 2D Transition Metal Compounds-based Electrocatalysts for Efficient nitrogen Reduction

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Chemical Research in Chinese Universities 2020年第4期36卷 648-661页

作者： DONG Wcnfei CHEN Xiaoyu PENG Juan LIU Wanyi JIN Xiaoyong ni gang LIU Zheng State Key Laboratoty of High-efficiency Utilization of Coal and Green Chemical Engineering National Demonstration Center for Experimental Chemistry EducationCollege of Chemistry and Chemical EngineeringNingxia UniversityYinchuan 750021P.R.China School of Materials Science and Engineeting Nanyang Technological UniversitySingapore 639798Singapore CINTRA CNRS NTU THALES Research Techno PlazaSingapore 639798Singapore Environmental Chemistry and Materials Centre Nanyang Environment and Water Research InstituteSingapore 639798Singapore

Ammonia is a commodity chemical with high added *** reduction of nitrogen has great promise for the sustainable synthesis of ammonia in recent *** of its rich resources and unique electronic structure and characteristics,2D transition metal compounds have been used as electrocatalysts for electro-chemical reduction of nitrogen for clean and sustainable production of ammonia,This review outlines the latest development in the use of 2D transition metal compounds as high-efficiency electrocatalysts for nitrogen ***(NRR).First,we introduce the N,reduction mechanism,and briefly summarize the performance indicators ofthe ***,we focused on the functionalization of unique 2D materials to design high-performance 2D electrocatalysts in respect of simulation calculation and experimental ***,the current challenges and future opportunities for NRR electrocatalvsts are introduced.

关键词： Electrochemical NH3 svnthesis Transition metal nitrogen fixation Electrocatalysis

Helioscopianoids A–Q,bioactive jatrophane diterpenoid esters from Euphorbia helioscopia

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Acta Pharmaceutica Sinica B 2018年第5期8卷 805-817页

作者： Zhenpeng Mai gang ni Yanfei Liu Zhao Zhang Li Li Naihong Chen Dequan Yu State Key Laboratory of Bioactive Substance and Function of Natural Medicines Institute of Materia Medica Chinese Academy of Medical Sciences and Peking Union Medical College

The EtOH extracts of the whole plants of Euphorbia helioscopia afforded 17 new jatrophane diterpenoid esters, helioscopianoids A–Q(1–17), along with eight known compounds(18–25). Their structures were elucidated by extensive spectroscopic methods and Mo_2(OAc)_4-induced ECD analysis,and the structures of compounds 1, 2, and 7 were confirmed by X-ray crystallography. Compounds 1–17 were evaluated for inhibitory effects on P-glycoprotein(P-gp) in an adriamycin(ADM)-resistant human breast adenocarcinoma cell line(MCF-7/ADR) and neuroprotective effects against serum deprivationinduced and rotenone-induced PC12 cell damage. Compounds 8 and 16 increased the accumulation of ADM in MCF-7/ADR cells by approximately 3-fold at a concentration of 20 μmol/L. Compound 8 could attenuate rotenone-induced PC12 cell damage, and compounds 2, 8, and 12 showed neuroprotective activities against serum deprivation-induced PC12 cell damage.

关键词： Euphorbia helioscopia Jatrophanes Helioscopianoids A–Q P-glycoprotein(ABCB1) inhibitory activity Neuroprotective effect

Determination of Trace Amount of Yttrium with Bromopyrogallol Red by solid-phase Spectrophotometry

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Rare Metals 2001年第3期20卷 202-204页

作者： Jinzhang Gao,gang ni, Li Yuan, Jingwan Kang Department of Chemistry, Northwest Normal University, Lanzhou 730070, China NW Normal Univ Dept Chem Lanzhou 730070 Peoples R China

A simple and sensitive method for the determination of trace amount of yttrium by solid-phase spectrophotometry has been studied. Yttrium can form a 1 : 1 complex with bromopyrogallol red (BPR) on resin, which was determined directly at 605 nm, pH=6.5. It has a highly sensitivity (epsilon = 6.3 x 10(6)) which is 300-fold higher than the corresponding spectrophotometry in solution. The method was applied to the determination of yttrium in churchite.

关键词： solid-phase spectrophotometry bromopyrogallol red (BPR) yttrium

Preparation of polystyrene/SiO_(2) nanocomposites by surface-initiated nitroxide-mediated radical polymerization

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Chinese Science Bulletin 2006年第13期51卷 1644-1647页

作者： ni gang YANG Wu BO Lili GUO Hao ZHANG Wenhao GAO Jinzhang Key Laboratory of Polymer Materials of Gansu Province College of Chemistry and Chemical Engineering Northwest Normal University Lanzhou 730070 China College of Chemistry and Chemical Engineering Ningxia University Yinchuan 750021 China

Polystyrene/SiO2 composite nanoparti- cles (PS-g-Silica) were prepared by an in-situ sur- face-initiated nitroxide-mediated radical polymeriza- tion. After SiO2 nanoparticles were treated by thionyl chloride (SOCl2), peroxide initiation groups were immobilized on their surfaces through a reaction with tertiary butyl hydroperoxide (TBHP). Then surface nitroxide-mediated radical polymerization was initi- ated and polystyrene was grafted on the surface of SiO2 particles. Composite nanoparticles were char- acterized by IR spectra, transmission electron mi- croscopy (TEM), atomic force microscopy (AFM) and thermogravimetry (TGA) and the results indicated that the surface-initiated nitroxide-mediated radical polymerization could be successfully used to synthe- size well-dispersive PS/SiO2 nanocomposites.

关键词：聚苯乙烯二氧化硅纳米复合材料游离基聚合 TEM TGA AFM

Growth and Cd Accumulation of Orychophragmus violaceus as Affected by Inoculation of Cd-Tolerant Bacterial Strains

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Pedosphere 2014年第3期24卷 322-329页

作者： LIANG Xia HE Chi-Quan ni gang TANG Gui-E CHEN Xue-Ping LEI Yan-Ru School of Environmental and Chemical Engineering Shanghai University

Beneficial interactions between microorganisms and plants, particularly in the rhizosphere, are a research area of global interest. Four cadmium(Cd)-tolerant bacterial strains were isolated from heavy metal-contaminated sludge and their effects on Cd mobility in soil and the root elongation and Cd accumulation of Orychophragmus violaceus were explored to identify the capability of metalresistant rhizobacteria for promoting the growth of O. violaceus roots on Cd-contaminated soils. The isolated strains, namely, Bacillus subtilis, B. cereus, B. megaterium, and Pseudomonas aeruginosa, significantly enhanced the plant Cd accumulation. The Cd concentrations in the roots and shoots were increased by up to 2.29- and 2.86-fold, respectively, by inoculation of B. megaterium, as compared with the uninoculated control. The bacterial strains displayed different effects on the shoot biomass. Compared with the uninoculated plants, the shoot biomass of the inoculated plants was slightly increased by B. megaterium and significantly decreased by the other strains. B. megaterium was identified as the best candidate for enhancing Cd accumulation in O. violaceus. Thus, this study provides novel insight into the development of plant-microbe systems for phytoremediation.

关键词： heavy metals phytoremediation plant-microbe systems rhizobacteria soil contamination