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Implementation of Interrogation Systems for Fiber Bragg Grating Sensors

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Photonic Sensors 2013年第3期3卷 283-288页

作者： Benjamin VARGHESE P. Dinesh KUMAR R. Mittu RAJU K. n. MADHUSOODAnAn Department of Instrumentation Cochin University of Science and Technology Cochin lndia

The development of two simple methods for wavelength-optical intensity modulation techniques for fiber Bragg grating （FBG） sensors is presented. The performance is evaluated by measuring the strain and temperature. The first method consists of a narrow band source, an optical circulator, an FBG; and a power meter. The source and Bragg reflected signal from the FBG need to be matched to get linear results with good power levels. The source spectral power levels are very critical in this study. The power reflected from a matched reference FBG is fed into the measuring FBG in the second method. Since the FBGs are matched, the entire power is reflected back initially. During the measurement, the change in the measurand causes the reflected power from the sensing FBG to vary. A costly high resolution spectrum analyzer is required only during the characterization of the FBG and source. The performances of two interrogators are compared by measuring the strain and temperature. In the second method, the strain measurements can be made insensitive to the temperature variation by selecting a source with a flat spectrum at the measurement range. Highlights of these methods are the portability, cost effectiveness and better resolution.

关键词： Fiber Bragg grating interrogator reflected power strain and temperature measurement

接头渗漏和土体渗透各向异性对盾构隧道渗流影响的数值模拟

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中南大学学报（自然科学版） 2023年第3期54卷 1012-1022页

作者：张晓周建蒋熠诚 HORRIS K n 浙江大学滨海和城市岩土工程研究中心浙江杭州310058 浙江大学浙江省城市地下空间开发工程技术研究中心浙江杭州310058

为了研究土体渗透各向异性对盾构隧道渗漏的影响,以上海地铁1号线为工程背景,首先,通过有限元数值软件,建立盾构隧道接头渗漏的计算模型;其次,将计算结果与解析解对比,验证数值模型的可靠性;再次,探究不同渗漏位置以及土体渗透各向异性... 详细信息

为了研究土体渗透各向异性对盾构隧道渗漏的影响,以上海地铁1号线为工程背景,首先,通过有限元数值软件,建立盾构隧道接头渗漏的计算模型;其次,将计算结果与解析解对比,验证数值模型的可靠性;再次,探究不同渗漏位置以及土体渗透各向异性比下,地下水渗入隧道对地表沉降以及隧道位移的影响;最后,提出不同渗漏位置下土体的临界渗透各向异性比。研究结果表明:对于修建于饱和软土地区的盾构隧道,土体渗透各向异性对地表以及隧道的影响与渗漏位置密切相关,隧道全部接头渗漏、仅上部接头渗漏、仅中部接头渗漏和仅底部接头渗漏等工况下,临界渗透各向异性比分别为1.6,1.1,1.3和1.4。当土体渗透各向异性比超过临界值时,需要考虑渗透各向异性的影响。当隧道全部接头渗漏时,忽略渗透各向异性会高估隧道以及地表的沉降,低估地表沉降槽的范围;当仅有一个接头渗漏时,忽略渗透各向异性会低估隧道的沉降、偏移、地表沉降以及地表沉降槽的范围。

关键词：渗透各向异性盾构隧道接头渗漏有限元

Recent progress on oxygen and hydrogen peroxide reduction reactions on Pt single crystal electrodes

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Chinese Journal of Catalysis 2020年第5期41卷 732-738页

作者： Valentín Briega-Martos Enrique Herrero Juan M.Feliu 阿利坎特大学电化学研究所阿利坎特西班牙

The oxygen reduction reaction(ORR)is probably the most important cathodic process in electrocatalysis because of its universal role as comburent in life and key applications in several fields such as fuel cells,corrosion processes or lithium-air *** many experimental and theoretical investigations that have been carried out during the last years and contributed to improve the knowledge about this reaction,the complete mechanism for the ORR is not elucidated yet[1].The ORR involves the exchange of 4 electrons and 4 protons for the complete reduction of O2 to water(Eq.1).The reaction mechanism is complex and implies the formation of several intermediates involving O=O bond scission and O–H bond formation.

关键词：巯基金纳米簇金属氧化物载体巯基配体一氧化碳氧化

催化剂对炭黑转变为纳米炭微球和碳管的影响(英文)

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新型炭材料 2015年第1期30卷 19-29页

作者： Vijayshankar Asokan Dorte nφrgaard Madsen Pawel Kosinski Velaug Myrseth The University of Bergen Department of Physics and Technology

以二茂铁和二茂镍为催化剂,采用化学气相沉积法在1 000℃下,炭黑(CB)转变为炭纳米微球和碳管。利用XRD,SEM,TEM,HR-TEM和Raman等对样品进行表征。结果表明,二茂铁和二茂镍质量比不同,可得到形貌不同的纳米炭的结构。与单金属催化剂相比... 详细信息

以二茂铁和二茂镍为催化剂,采用化学气相沉积法在1 000℃下,炭黑(CB)转变为炭纳米微球和碳管。利用XRD,SEM,TEM,HR-TEM和Raman等对样品进行表征。结果表明,二茂铁和二茂镍质量比不同,可得到形貌不同的纳米炭的结构。与单金属催化剂相比,采用双金属催化剂合成的纳米炭结构具有高结晶度。催化剂颗粒填充在碳管内部或包裹在碳管外部,主要取决于催化剂与炭黑的质量比。当炭黑∶二茂铁∶二茂镍为1∶2∶2时,得到结晶度高的催化剂包裹多壁纳米炭微球结构。

关键词：炭黑炭微球碳管催化转变气相沉积

Paratyphoid fever- Emerging problem in South India

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Asian Pacific Journal of Tropical Medicine 2010年第10期3卷 815-817页

作者： Ragini Bekur K.E.Vandana K.n.Shivashankara Rohit Valsalan Vishwanath Sathyanarayanan Department of Medicine Kasturba Medical CollegeManipal UniversityManipalUdupiKarnatakaIndia-576104 Department of Microbiology Kasturba Medical CollegeManipal UniversityManipalUdupiKarnatakaIndia-576104

Objective:To review the clinical profile and drug susceptibilities of Salmonella paratyphi A in a tertiary care ***:Retrospective analyses of 113 patients with paratyphoid fever and 101 culture proven Salmonella paratyphi A infection were included in the *** study extended over a period of 3 years(2006-2008).Diagnosis of patients were based on clinical features,serology and blood *** drug susceptibility testing of the isolates were performed by the disc diffusion *** presentation,laboratory parameters,susceptibility patterns of isolates,treatment and clinical response were ***:Of the 113 cases,77(68.4%) were males and 36 were females(32.8%),which included 2 pediatric *** was the most common symptom(100.0%) followed by loose stools(37.2%),headache(35.4%),myalgia(31.9%), pain abdomen(29.2%),dry cough(19.5%) and vomiting(13.3%).All patients were clinically cured. Majority of the isolates(46%) were resistant to cotrimoxazole in 2006,however they became 100% sensitive in 2007 and *** the strains became 100% sensitive to ampicillin and chloramphenicol only in *** 2006 the sensitivity of organisms to ciprofloxacin was 89% but in 2007 and 2008 there has been an increasing resistance to ciprofloxacin(46% and 86%) *** 3 isolates(8.1%) were resistant to ceftriaxone in 2006,showed 100% sensitivity in *** drugs used were ceftriaxone in 100 cases(88.4%) and ciprofloxacin in 13 cases(11.6%).One patient had relapse of paratyphoid fever after treatment with ciprofloxacin which responded to ***:Paratyphoid fever A is one of the emerging infections and a significant problem in *** increasing resistance to fluoroquinolones is *** monitoring of drug susceptibilities is mandatory in instituting appropriate therapy.

关键词： Paratyphoid fever Salmonella paratyphi A Antimicrobial susceptibility

U-Doped Y-Ba-Cu-O Melt-Processed Superconductor

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Tsinghua Science and Technology 2003年第3期8卷 242-250页

作者： n.Hari Babu D.A.Cardwell C.D.Tarrant K.R.Schneider IRC in Superconductivity University of CambridgeMadingley RoadCambridgeCB3 OHEUKIRC in SuperconductivityUniversity of CambridgeMadingley RoadCambridgeCB3 OHEUKUrenco Power Technologies Ltd.CapenhurstCheshireCH1 6ERUKUrenco Power Technologies Ltd.CapenhurstCheshireCH1 6ERUK

Large grain Y-Ba-Cu-O (YBCO) superconductors doped with various amounts of depleted uranium oxide have been fabricated by top seeded melt growth (TSMG). The effect of depleted UO2 on the large grain microstructure has been studied systematically in samples with and without added Pt. Addition of uranium oxide results in the formation of U-phase particles of dimensions of a few hundred nanometers with an approximately spherical morphology in the superconducting YBa2Cu3O7-δ(Y-123) phase matrix. Addition of Y2O3 to the uranium doped precursor powder, rather than Y-211, yields a significantly finer distribution of second phase particles. The chemical composition of the U-phase particles, found in samples with no Pt addition, has been identified as Y2Ba4CuUOy, which exhibits paramagnetic behaviour. It has been confirmed experimentally that this phase forms during the peritectic solidification process. Magnetic measurements show that U-doped melt processed YBCO exhibits improved critical current densities and trapped fields compared to un-doped material.

关键词： superconductor critical current density uranium oxide

Selective Deactivation of Gibberellins below the Shoot Apex is Critical to Flowering but not to Stem Elongation of Lolium

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Molecular Plant 2008年第2期1卷 295-307页

作者： Rod W. King Lewis n. Mander Torben Asp Colleen R MacMillan Cheryl A. Blundell Lloyd T. Evans CSIRO Plant Industry Canberra ACT 2600 Australia Research School of Chemistry Australian National University Canberra ACT 0200 Australia Department of Genetics and-Biotechnology University of Aarhus 4200 Slagelse Denmark Present Address: EnSIS PO Box E 4008 Kingston ACT 2604 Australia

Gibberellins （GAs） cause dramatic increases in plant height and a genetic block in the synthesis of GA1 explains the dwarfing of Mendel＇s pea. For flowering, it is GAs which is important in the long-day （LD） responsive grass, Loliurn. As we show here, GA1 and GA4 are restricted in their effectiveness for flowering because they are deactivated by C-2 hydroxylation below the shoot apex. In contrast, GAs is effective because of its structural protection at C-2. Excised vegetative shoot tips rapidly degrade [14C]GA1, [14C]GA4, and [14C]GA20 （〉80% in 6 h）, but not [14C]GAs. CoincidentaUy, genes encoding two 2β-oxidases and a putative 16-17-epoxidase were most expressed just below the shoot apex （〈3 mm）. Further down the immature stem （〉4 mm）, expression of these GA deactivation genes is reduced, so allowing GA1 and GA4 to promote sub-apical stem elongation. Subsequently, GA degradation declines in florally induced shoot tips and these GAs can become active for floral development. Structural changes which stabilize GA4 confirm the link between florigenicity and restricted GA 2β-hydroxylation （e.g. 2α-hydroxylation and C-2 di-methylation）. Additionally, a 2-oxidase inhibitor （Trinexapac Ethyl） enhanced the activity of applied GA4, as did limiting C-16,17 epoxidation in 16,17-dihydro GAs or after C-13 hydroxylation. Overall, deactivation of GA1 and GA4 just below the shoot apex effectively restricts their florigenicity in Loliurn and, conversely, with GAs, C-2 and C-13 protection against deactivation allows its high florigenicity. Speculatively, such differences in GA access to the shoot apex of grasses may be important for separating floral induction from inflorescence emergence and thus could influence their survival under conditions of herbivore predation.

关键词： Selective Deactivation Shoot Apex Stem Elongation of Lolium

Influences of Annealing Temperature and Doping Concentration on Microstructural and Optical Properties of CeO_2:Sm^(3+) nanocrystals

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Acta Metallurgica Sinica(English Letters) 2015年第6期28卷 758-765页

作者： G.Vimal Kamal P.Mani P.R.Biju Cyriac Joseph n.V.Unnikrishnan M.A.Ittyachen School of Pure and Applied Physics Mahatma Gandhi University

nanocrystals of CeO2 with different doping concentrations of Sm3＋ were synthesized by a novel and cost- effective method. The crystal structure, morphology and particle size were systematically investigated by X-ray diffraction, scanning electron microscopy and transmission electron microscopy. Effects of the annealing temperature and doping concentrations on the microstructural properties of the crystals were studied. X-ray diffraction analysis indicates that the cubic structure of the CeO2 is not affected by the doping of Sm3＋ up to a doping concentration of 20%. Different structural parameters such as lattice constant, surface area, bulk density and porosity of the crystal were determined and discussed. Microscopic images of the CeO2：Sm3＋ suggest that the thermal decomposition of oxalate precursor is a suitable synthesis pathway to produce uniform-sized microparticles and nanoparticles. The influences of annealing temPerature and doping concentration of Sm3＋ on the optical properties of the nanocrystals were also discussed. The photoluminescence excitation spectra reveal that the charge transfer band is redshifted with increasing annealing temperatures. Emission attains its maximum intensity for Sm3＋ concentration of 1%, and higher concentrations lead to emission quenching.

关键词： Microstructure Strain Photoluminescence CeO2:Sm3+ nanocrystal Dopingconcentration Annealing temperature

Targeting MYC-driven lymphoma:lessons learned and future directions

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Cancer Drug Resistance 2023年第2期6卷 205-222页

作者： Sandra Martínez-Martín Marie-Eve Beaulieu Laura Soucek 无 Peptomyc S.L. Vall d’Hebron Barcelona Hospital CampusBarcelona 08035Spain Preclinical&Translational Research Program Vall d’Hebron Institute of Oncology(VHIO)Vall d’Hebron Barcelona Hospital CampusBarcelona 08035Spain Department of Biochemistry and Molecular Biology Universitat Autònoma de BarcelonaBellaterra 08193Spain InstitucióCatalana de Recerca i Estudis Avançats(ICREA) Barcelona 08010Spain

MYC plays a central role in tumorigenesis by orchestrating cell proliferation,growth and survival,among other transformation *** particular,MYC has often been associated with *** fact,MYC overexpressing lymphomas such as high-grade B-cell lymphoma(HGBL)and double expressor diffuse large B-cell lymphomas(DLBCL),are considered addicted to *** such a context,MYC targeting therapies are of special interest,as MYC withdrawal is expected to result in tumor ***,whether high MYC levels are always predictive of increased sensitivity to these approaches is not clear *** though no MYC inhibitor has received regulatory approval to date,substantial efforts have been made to investigate avenues to render MYC a druggable ***,we summarize the different classes of molecules currently under development,which mostly target MYC indirectly in aggressive B-cell lymphomas,paying special attention to subtypes with MYC/BCL2 or BCL6 translocations or overexpression.

关键词： High-grade B-cell lymphoma double expressor lymphoma MYC MYC therapies