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Controlled synthesis and optical properties of Ce^(3+)/Tb^(3+) co-doped BaGdF_5 nanocrystals

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Rare Metals 2015年第9期34卷 673-678页

作者： Chun-yan Cao An Xie Xiao-guang Yu College of Mathematics and Physics Jinggangshan University School of Materials Science and Engineering Xiamen University of Technology

Based on a hydrothermal method, the Ce3+/Tb3+ co-doped Ba Gd F5 nanocrystals were synthesized by controlling the introduction concentration of Ba2+ and Gd3+. The samples were characterized by X-ray diffraction(XRD), field emission scanning electron microscopy(FESEM) images, photoluminescence(PL) excitation, and emission spectra, as well as the photoluminescence dynamic decay curves. With the increase of the Ba2+ concentration in the synthesis procedure, the positions of diffraction peaks of XRD patterns move toward lower degree, and the case of the samples synthesized with the increase of the Gd3+ concentration is contrary, which consists well with each other. The FE-SEM images suggest that the BaGdF5 nanocrystals are in spherical morphology,and the average diameters decrease with the increase of Ba2+ or Gd3+ concentration. For the 4f–5d transition of Ce3+ is sensitive to the environment of local lattice, the PL excitation and emission spectra of the samples are different. The 4f–4f transition of Tb3+ also presents different optical properties in different host lattices. The variations of the optical properties of Ce3+ and Tb3+ as well as the lifetime of the 5D4+7F5 emission of Tb3+ are also consistent well with each other in the two series of samples.

关键词： Hydrothermal synthesis Optical properties Nanocrys

Purification and Immunity Analysis of Recombinant 6His-HPT Protein Expressed in ***

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Biomedical and Environmental Sciences 2003年第2期16卷 149-156页

作者： LI-CHEN yanG zhen ZHU XIAO-guang yanG Plant Genetic Manipulation Laboratory Institute ofGeneticsChinese Academy of SciencesBeijing 100101China Key laboratory of Trace Element Nutrition ofthe Ministry of Health ChinaInstitute of Nutrition and Food SafetyChinese Centerfor Diseases Control and PreventionBeijing 100050Chin

To obtain HPT protein (Hygromycin B Phosphotransferase), a kind of plant selective maker gene product expressed from *** and to prepare the polyclonal antibody (pAbs) against it. Methods HPT cDNA fragment was obtained by PCR and was inserted into the prokaryotic expressing vector pBV222. Then the constructed recombinant plasmid pBV222-HPT was transfered into *** DH5?for HPT expression. The recombinant expressing system was confirmed by restriction endonuclease digestion, DNA sequencing and protein expression. *** cells were lysed by sonication and detergent dissolution. After cell membrane was extracted, the inclusion bodies were denatured by 8 mol/L Urea and purified with metal chelate affinity chromatography on Ni-NTA agarose under denaturing condition. The purified 6His-HPT was characterized by SDS-PAGE, and used to immunize rabbit. The titer and specificity of antisera were detected by ELISA and Western blot respecitively. Results Analysis of DNA sequence and restricted enzymes showed that the sequence of PBV222-HPT plasmid was correct. The amount of recombinant HPT expressed in *** accounted for 30% of total cellular proteins. From 1 liter of fermentative bacteria about 22 milligrams of pure recombinant HPT was isolated with purity above 95%. The recombinant HPT protein could produce high titer antiserum in rabbits and show good immunity activity. Western blot showed specific binding reaction between the antiserum to the purified 6His-HPT protein and their expressed products (plants protein and bacterial protein). Conclusion HPT protein can be expressed and purified from *** by a relatively simple method, which has high immunity activity.

关键词： Organisms Genetically Modified DNA Bacterial Electrophoresis Polyacrylamide Gel Escherichia coli Genetic Engineering Genetic Markers Phosphotransferases (Alcohol Group Acceptor) Plasmids Polymerase Chain Reaction Recombinant Proteins Research Support Non-U.S. Gov't

双掺杂LiNbO_3晶体光折变效应图像存储特性

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山东大学学报（理学版） 2004年第3期39卷 75-79页

作者：张艳珍许心光许贵宝胡大伟王正平邵宗书徐悟生徐玉恒山东大学晶体材料国家重点实验室山东济南250100 哈尔滨工业大学应用化学系黑龙江哈尔滨150001

研究了系列双掺杂(Ce:Fe,Mn:Fe,Ce:Mn)以及不同后处理态(生长态、还原态和氧化态)铌酸锂晶体的透过率光谱和光折变全息存储特性.实验结果表明高掺杂铌酸锂样品的透过率光谱范围较窄;氧化态样品具有较大的透过率光谱范围;还原态样品具有... 详细信息

研究了系列双掺杂(Ce:Fe,Mn:Fe,Ce:Mn)以及不同后处理态(生长态、还原态和氧化态)铌酸锂晶体的透过率光谱和光折变全息存储特性.实验结果表明高掺杂铌酸锂样品的透过率光谱范围较窄;氧化态样品具有较大的透过率光谱范围;还原态样品具有较大的光折变二波耦合增益特性.难于同时获得大的波耦合增益和图像存储质量.

关键词：铌酸锂晶体双掺杂光折变效应透过率光谱

Laser-induced breakdown spectroscopy in Asia

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Frontiers of physics 2016年第6期11卷 231-255页

作者： zhen-zhenWang Yoshihiro Deguchi zhen-zhen Zhang Zhe Wang Xiao-yan Zeng Jun-Jie yan State Key Laboratory of Multiphase Flow in Power Engineering Xi'an Jiaotong University Xi'an 710049 China Graduate School of Advanced Technology and Science Tokushima University Tokushima 770-8501 Japan State Key Lab of Power Systems Department of Thermal Engineering Tsinghua-BP Clean Energy Center Tsinghua University Beijing 100084 China Wuhan National Laboratory for Optoelectronics (WNLO) Huazhong University of Science and Technology Wuhan ~3007~ China

Laser-induced breakdown spectroscopy (LIBS) is an analytical detection technique based on atomic emission spectroscopy to measure the elemental composition. LIBS has been extensively studied and developed due to the non-contact, fast response, high sensitivity, real-time and multi-elemental detection features. The development and applications of LIBS technique in Asia are summarized and discussed in this review paper. The researchers in Asia work on different aspects of the LIBS study in fundamentals, data processing and modeling, applications and instrumentations. According to the current research status, the challenges, opportunities and further development of LIBS technique in Asia are also evaluated to promote LIBS research and its applications.

关键词： laser-induced breakdown spectroscopy (LIBS) quantitative analysis signal enhancement applications challenges

Validation of methods for effective orifice area measurement of prosthetic valves by two-dimensional and Doppler echocardiography following transcatheter self-expanding aortic valve implantation

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Journal of Geriatric Cardiology 2020年第12期17卷 766-774页

作者： Ming-Hu XIAO Yong-Jian WU Jing-Jin WANG guang-Yuan SONG Jian-De WANG zhen-Hui ZHU Xu WANG zhen-yan ZHAO Hao WANG Department of Echocardiography Fuwai HospitalNational Center for Cardiovascular DiseasesChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijingChina Department of Cardiology Fuwai HospitalNational Center for Cardiovascular DiseasesChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijingChina Department of Surgery Fuwai HospitalNational Center for Cardiovascular DiseasesChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijingChina

Background The effective orifice area(EOA)is utilized to characterize the hemodynamic performance of the transcatheter heart valve(THV).However,there is no consensus on EOA measurement of self-expanding *** aimed to compare two echocardiographic methods for EOA measurement following transcatheter self-expanding aortic valve *** EOA was calculated according to the continuity *** methods were *** Method 1 and Method 2,the left ventricular outflow tract diameter(LVOTd)was measured at the entry of the prosthesis(from trailing-to-leading edge)and proximal to the prosthetic valve leaflets(from trailing-toleading edge),*** velocity-time integral(VTI)of the LVOT(VTILVOT)was recorded by pulsed-wave Doppler(PW)from apical *** region of the PW sampling should match that of the LVOTd measurement with precise *** mean transvalvular pressure gradient(MG)and VTI of THV was measured by Continuous wave *** A total of 113 consecutive patients were *** mean age was 77.2±5.5 years,and 72 patients(63.7%)were ***1 with the use of Method 1 was larger than EOA2(1.56±0.39 cm2 vs.1.48±0.41 cm2,P=0.001).MG correlated better with the indexed EOA1(EOAI1)(r=-0.701,P<0.001)than EOAI2(r=-0.645,P<0.001).According to EOAI(EOAI≤0.65 cm2/m2,respectively),the proportion of sever prosthesis-patient mismatch with the use of EOA1 was lower than EOA2(12.4%vs.21.2%,P<0.05).Compared with EOA2,EOA1 had lower interobserver and intra-observer variability(intra:0.5%±17%vs.3.8%±22%,P<0.001;inter:1.0%±9%vs.3.5%±11%,P<0.001).Conclusions For transcatheter self-expanding valve EOA measurement,LVOTd should be measured in the entry of the prosthesis stent(from trailing-to-leading edge),and VTILVOT should match that of the LVOTd measurement with precise localization.

关键词： Aortic valve stenosis Echocardiography Transcatheter aortic valve implantation

Cold-modeling study of a circulating fluidized bed reactor for flue gas desulfurization (FGD)

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Journal of Environmental Sciences 2000年第2期12卷 88-94页

作者： Qian, Feng Liu, Tong-guang Zhang, zhen-Fang Department of Chemical Engineering Beijing Institute of Light Industry Beijing 100037 China

Short residence time of the sorbent in the gas stream and formation of a dense layer of reaction product surrounding its surface influence the sulfur removal efficiency. A practical means of improving the process performance is to employ fluidized bed reaction in replacement of entrained bed reaction on normally used in cool side desulfurizaiton. This paper describes cold modeling study of a circulating fluidized bed reactor. Several aspects of the problem are discussed: fluidization behavior of CaO, attrition of the sorbent and solids entrainment from the fluidized bed. Mechanisms and key controlling parameters are identified, and an integral model based on rate of attrition and mass balance is developed for predicting steady state mass flows and particle size distributions of the system. A process flow scheme is finally presented for conducting desulfurization tests in the second stage of the study.

关键词： circulating fluidized bed reactor flue gas desulfurization cold modeling study CLC number: X701 Document code: A

A Chandra study of the massive, distant galaxy cluster SDSS J0150–1005

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Research in Astronomy and Astrophysics 2013年第10期13卷 1155-1162页

作者： zhen-zhen Qin Hai-guang Xu Jing-Ying Wang Jun-Hua Gu Department of Physics Shanghai Jiao Tong University National Astronomical Observatories Chinese Academy of Sciences

We present a study of a fossil cluster,SDSS J0150–1005（z 0.364）,with high spatial resolution based on the imaging spectroscopic analysis of Chandra *** Chandra X-ray image shows a relaxed and symmetric morphology,which indicates that SDSS J0150–1005 is a well-developed galaxy cluster with no sign of a recent *** to the isothermal model,its global gas temperature is 5.73±0.80 keV,and the virial mass is 6.23±1.34×1014M⊙.Compared with the polytropic temperature model,the mass calculated based on the isothermal model is overestimated by 49%±*** central gas entropy,S0.1 r200=143.9±18.3 keV cm2,is significantly lower than the average value of normal galaxy clusters with similar *** results indicate that SDSS J0150–1005 formed during an early epoch.

关键词： galaxies:clusters:general galaxies:evolution galaxies:halos—intergalactic medium X-rays:galaxies:clusters

Distributed privacy protection strategy for MEC enhanced wireless body area networks

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Digital Communications and Networks 2020年第2期6卷 229-237页

作者： yan zhen Hanyong Liu Key Laboratory of Optical Communication and Networks in Chongqing Key Laboratory of Ubiquitous Sensing and Networking in ChongqingChongqing400065China School of Communication and Information Engineering Chongqing University of Posts and TelecommunicationsChongqing400054China State Grid Information and Telecommunication Co.Ltd Beijing100031China

With the rapid development and widespread application of Wireless Body Area Networks(WBANs),the traditional centralized system architecture cannot handle the massive data generated by the edge ***,in order to ensure the security of physiological privacy data and the identity privacy of patients,this paper presents a privacy protection strategy for Mobile Edge Computing(MEC)enhanced WBANs,which leverages the blockchain-based decentralized MEC paradigm to support efficient transmission of privacy information with low latency,high reliability within a high-demand data security *** this basis,the Merkle tree optimization model is designed to authenticate nodes and to verify the source of physiological ***,a hybrid signature algorithm is devised to guarantee the node anonymity with unforgeability,data integrity and reduced *** security performance analysis and simulation results show that our proposed strategy not only reduces the delay,but also secures the privacy and transmission of sensitive WBANs data.

关键词： Wireless body area networks Blockchain Mobile edge computing Hybrid signature algorithm Merkle tree optimization model

Construction of a Bacterial Artificial Chromosome Library of TM-1,a Standard Line for Genetics and Genomics in Upland Cotton

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Journal of Integrative Plant Biology 2009年第1期51卷 107-112页

作者： yan Hu Wang-zhen Guo Tian-zhen Zhang National Key Laboratory of Crop Genetics & Germplasm Enhancement Cotton Research Institute Nanjing Agricultural University Nanjing 210095 China

A bacterial artificial chromosome （BAC） library was constructed for Gossypium hirsutum acc. TM-1, a genetic and genomic standard line for Upland cotton. The library consists of 147 456 clones with an average insert size of 122.8 kb ranging from 97 to 240 kb. About 96.0% of the clones have inserts over 100 kb. Therefore, this library represents theoretically 7.4 haploid genome equivalents based on an AD genome size of 2 425 Mb. Clones were stored in 384 384- well plates and arrayed into multiplex pools for rapid and reliable library screening. BAC screening was carried out by four-round poiymerase chain reactions using 23 simple sequence repeats （SSR） markers, three sequence-related amplified polymorphism markers and one pair of primers for a gene associated with fiber development to test the quality of the library. Correspondingly, in total 92 positive BAC clones were identified with an average four positive clones per SSR marker, ranging from one to eight hits. Additionally, since these SSR markers have been localized to chromosome 12 （A12） and 26 （D12） according to the genetic map, these BAC clones are expected to serve as seeds for the physical mapping of these two homologous chromosomes, sequentially map-based cloning of quantitative trait loci or genes associated with important agronomic traits.

关键词： bacterial artificial chromosome library polymerase chain reaction screening simple sequence repeats markers TM-1 upland cotton.