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Journal of Rare Earths 2010年第4期28卷 493-497页

作者： s.m. moses kennedy Department of Physics S.S.N. College of Engineering Rajiv Gandhi Salai Kalavakkam-603 110 Chennai Tamil Nadu India

The variation of the optical absorption (OA) and photoluminescence (PL) spectra with temperature was studied on γ-irradiated CaF2:Dy:Pb:Na single crystals. The OA spectrum showed bands around 2.05, 3.20, 3.82 and 6.20 eV which could be attributed to different sodium associated (sA) colour centres (CCs) such as.m.a and RA+ . Heating the crystal indicated the annihilation and formation of different sACCs. The excitation spectrum for the characteristic Dy3+ emission at 2.14 eV immediately after irradiation was...

关键词： calcium fluoride optical absorption photoluminescence colour centres dysprosium lead sodium rare earths

Thermoluminescence studies on γ-irradiated CaF_2:Dy:Pb:Na single crystals

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Journal of Rare Earths 2009年第2期27卷 187-191页

作者： s.m.silla moses kennedy Department of Physics SSN College of EngineeringSSN NagarRajiv Gandhi SalaiChennai-603 110Tamil Nadu India

Therrnoluminescence （TL） glow, thermoluminescence emission （TLE） and thermal decay （TD） of optical absorption （OA） bands were studied on γ-irradiated CaF2：Dy （0.010at.%）：Pb （0.188at.%）：Na （0.026at.%） single crystals （hereafter called crystal-I）. The TL glow exhibited four glow peaks in the temperature region 300-500 K. The TL response with dose was studied up to -7.5 kGy. The total glow showed linear, supra linear and exponential growth with dose. The TLE showed bands characteristic of Dy^3＋ ions （around 1.65, 1.87, 2.18 and 2.63 eV） and sodium associated （sA） colour centres （CCs） such as.m.a （around 1.67 eV） and XNa （a new sA CC, with an emission band around 2.63 eV）. The OA bands of mNa CC around 3.23 and 2.07 eV were found to decrease with temperature almost in accordance with the TL glow. The R＋A centre absorption around 2.48 eV was found to grow with temperature initially and then decayed. The formation/growth of the CCs R＋A and XNa might be from the conversion of the irradiation produced CC mNa. An attempt was.m.de to explain the TL mechanism in the present system.

关键词： CaF2:Dy:Pb:Na thermoluminescence thermoluminescence emission colour centres rare earths

Photoluminescence properties of a novel orange-red emitting Ba_2CaZn_2si_6O_(17):sm^(3+)phosphor

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Journal of Rare Earths 2016年第6期34卷 576-582页

作者： G.Annadurai s.m.silla moses kennedy V.sivakumar Department of Physics S.S.N.College of EngineeringRajiv Gandhi SalaiKalavakkam-603 110ChennaiTamil NaduIndia saveetha Engineering College Thandalam-602105ChennaiIndia

Novel orange-red emitting Ba_2Ca_（1–x）Zn_2si_6O_（17）：x sm^（3＋）（0.02≤x≤0.08） phosphors were synthesized using conventional solid-state reaction method under air atmosphere. The phase formation of the s.m.les was characterized by powder X-ray diffraction patterns. scanning electron microscopy（s.m. and photoluminescence properties were also investigated. The narrow excitation and emission spectra indicated the typical 4f-4f transitions of sm^（3＋）. The dominant excitation line was around 405 nm attributed to ~6H_（5/2）→ ~4F_（7/2） and the emission spectrum consisted of four emission peaks at 562, 600, 647, and 708 nm corresponding to the various transitions ~4G_（5/2） to ~6HJ（J=5/2, 7/2, 9/2 and 11/2） of the sm^（3＋） ions in the s.m. order. The strongest emission band located at 600 nm was attributed to ~4G_（5/2）→~6H_（7/2） transition of sm^（3＋）, producing bright orange-red color emission. The optimal dopant concentration of sm3＋ ion in Ba_2CaZn_2si_6O_（17）：x sm^（3＋） phosphor was around 4 mol.% and the critical transfer distance（Rc） of sm^（3＋） was calculated to be 2.65 nm. Decay time varied with the sm^（3＋） concentrations in Ba_2 CaZn_2si_6O_（17） phosphors. In addition, the Commission International del＇Eclairagethe（CIE） chromaticity coordinates of Ba_2Ca_（0.96）Zn_2si_6O_（17）：0.04sm^（3＋） phosphor was located in the orange-red region（0.547, 0.450） and the correlated color temperature（CCT） was 2543 K. The present results indicated that sm^（3＋） activated Ba_2CaZn_2si_6O_（17） phosphors.m.y be used as an orange-red emitting phosphor for near-ultraviolet（n-UV） based white light emitting diodes（WLEDs） applications.

关键词： sm^(3+) phosphors photoluminescence WLEDs rare earths

The Global Boundary stratotype section and Point （GssP） for the base of the Cenomanian stage, mont Risou, Hautes-Alpes, France

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Episodes 2004年第1期27卷 21-32页

作者： W.J.kennedy A.s.Gale J.A.Lees.m.Caron OxfordUniversitymuseumofNaturalHistory ParksRoadOxfordOXI3PWU.K. DepartmentofPalaeontology TheNaturalHistoryMuseumCromwellRoadLondonSW75BPU.K.andSchoolofEarthandEnvironmentalSciencesUniversityofGreenwichChathamMaritimeCampusChathamKentME44AWU.K. ResearchschoolofGeologicalandGeophysicalsciences BirkbeckCollegeandUniversityCollegeLondonGowerStreetLondonWCIE6BTU.K. InstitutdeGeologie UniversitedeFribourgCH-1700FribourgSwitzerland.

Following the unanimous recommendation of the International Commission on stratigraphy, the Global boundary stratotype section and Point (GssP) for the base of the Cenomanian stage is defined at a level 36 metres below the top of the marnes Bleues Formation, a level that corresponds to the the first appearance of the planktonic foraminiferan Rotalipora globotruncanoides sigal, 1948, on the south side of mont Risou, east of Rosans, Haute-Alpes, France, where it can be placed in the context of a series of secondary marker levels based on nannofossils, planktonic foraminifera, ammonites,and an ornate δ^13C curve.

关键词：地层学地层分界线层型地质构造

Brevipedicelones D and E,Two C-O-C Flavonoid Dimmers from the Leaves of Garcinia brevipedicellata and Anti-onchocercal Activity

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Natural Products and Bioprospecting 2019年第1期9卷 61-68页

作者： mirabel Akongwi Anastasie ETih kennedy D.Nyongbela moses s.m.e Raphael T.Ghogomu Bernard Bodo Department of Organic Chemistry Faculty of ScienceUniversity of Yaounde 1P.O.Box 812YaoundeCameroon Pharmacochemistry Research Laboratory Department of ChemistryFaculty of ScienceUniversity of BueaP.O.Box 63BueaSouth West RegionCameroon Faculty of science ANDI Centre of Excellence on Onchocerciasis ResearchUniversity of BueaP.O.Box 63BueaSouth West RegionCameroon Laboratoire de Chimie des substances Naturelles Muse´um National d’Histoire Naturelle63 Rue Buffon75005 ParisFrance

A novel isoflavone–chromone flavonoid C–O–C dimmer,brevipedicelone D(1),along with one new C–O–C biflavonoid derivative,brevipedicelone E(2),were isolated from the ethyl acetate extract of the leaves of Garcinia brevipedicellata,a medicinal plant used in folk medicine in parts of *** structures were elucidated by extensive spectroscopic techniques,including 1D-and 2D-NmR,ms experiments,as well as comparing their spectral data with those of known ***-onchocercal screening of 1 showed moderate inhibition of adult worm motility of Onchocerca ochengi by 60%at the highest concentration(20 μg/mL)and inhibited motility of both the juvenile worms of *** and Loa loa by 90%at this s.m. concentration.

关键词： Garcinia brevipedicellata Brevipedicelone Anti-onchocercal activity

Co-Doped ZnO Nanoparticles:structural,morphological,Optical,magnetic and Antibacterial studies

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Journal of materials science & Technology 2014年第11期30卷 1108-1117页

作者： N.mohamed Basith J.Judith Vijaya L.John kennedy m.Bououdina s.Jenefar V.Kaviyarasan Catalysis & Nanomaterials Research Laboratory Department of ChemistryLoyola College (Autonomous) P.G.& Research Department of Chemistry The New College (Autonomous) materials Division School of Advanced SciencesVellore Institute of Technology (VIT) UniversityChennai Campus Nanotechnology Centre University of BahrainPO Box 32038Bahrain Department of Physics College of ScienceUniversity of BahrainPO Box 32038Bahrain Centre for Advanced studies in Botany University of Madras

Un-doped and Co-doped ZnO nanoparticles （NPs） with different weight ratios （0.5, 1.0, 1.5, and 2.0 wt% of Co） were synthesized by a facile and rapid microwave-assisted combustion method using urea as a fuel. The prepared NPs were characterized by X-ray diffraction （XRD）, high resolution scanning electron microscopy （HR-s.m., energy dispersive X-ray analysis （EDX）, diffuse reflectance spectroscopy （DRs）, photoluminescence （PL） spectroscopy and vibrating s.m.le magnetometry （Vsm）. XRD patterns refined by the Rietveld method indicated that Co-doped ZnO had a single pure phase with wurtzite structure suggesting that Co^2＋ ions would occupy Zn^2＋ ionic sites within the ZnO crystal lattice. Interestingly, the morphology was found to convert substantially from grains to nanoparticles with close-packed periodic array of hexagonal-like shape and then into randomly distributed spherical NPs with the variation of Co-content. The optical band gap estimated using DRs was found to be red-shifted from 3.22 eV for the un-doped ZnO NPs then decrease up to 2.88 eV with increasing Co-content. PL spectra showed a strong green emission band thus confirming the formation of pure single ZnO phase. magnetic studies showed that Co-doped ZnO NPs exhibited room temperature ferromagnetism （RTFm） and that the saturation magnetization attained a maximum value of 2.203 × 10^-3 emu/g for the highest Co-content. The antibacterial studies performed against a set of bacterial strains showed that the 2.0 wt% Co-doped ZnO NPs possessed a greater antibacterial effect.

关键词： Nanoparticles Optical properties Ferromagnetism Antibacterial activity

synthesis, characterization and electrochemical evaluation of anticorrosion property of a tetrapolymer for carbon steel in strong acid media

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Chinese Journal of Chemical Engineering 2019年第4期27卷 965-978页

作者： shamsuddeen A.Haladu saviour A.Umoren shaikh A.Ali moses m.solomon Abdul-Rashid I.mohammed Department Basic sciences and Humanities College of Engineering Imam Abdulrahman Bin Faisal University Dammam 31451 Saudi Arabia Centre of Research Excellence in Corrosion Research Institute King Fahd University of Petroleum and Minerals Dhahran 31261 Saudi Arabia Department of Chemistry King Fahd University of Petroleum & Minerals Dhahran 31261 Saudi Arabia Centre for Engineering Research Research Institute King Fahd University of Petroleum and Minerals Dhahran 31261 Saudi Arabia

A novel tetrapolymer(TP) consisting of carboxylate, sulphonate, phosphonate and sulfur dioxide based comonomers was synthesized using Butler cyclopoymerization technique. The synthesized tetrapolymer was characterized using FTIR,1H-NmR,13CNmR and elemental analysis. The performance of the tetrapolymer as a corrosion inhibitor for st37 carbon steel in 15% HCl and 15% H2sO4 acid media was assessed using electrochemical impedance spectroscopy(EIs), linear polarization resistance(LPR), potentiodynamic polarization(PDP) and electrochemical frequency modulation(EFm) techniques. The influence of addition of a small amount of KI on the corrosion inhibition efficiency of TP was also assessed. Results obtained showed that the tetrapolymer moderately inhibited the corrosion of st37 steel in the acid media with protection efficiency of 79.5% and 61.1% at the optimum concentration of 1000 mg·L^-1 studied in HCl and H2sO4 media respectively. On addition of 5 mmol·L^-1 KI to the optimum tetrapolymer concentration, the protection efficiency was upgraded to 90.6% and 93.5% in HCl and H2sO4 environment, respectively. The enhanced performance of the polymer in the presence of KI is due to synergistic action deduced from synergism parameter(s1) which was found to be greater than *** tetrapolymer afforded the corrosion inhibition of st37 steel in the acid media by virtue of adsorption of the polymer molecules on the steel surface which was confirmed by ATR-FTIR analysis of the adsorbed film extracted from the steel surface. TP + KI formed complex with st37 steel surface in H2sO4 solution but not in HCl solution.

关键词： Tetrapolymer metal Acid corrosion Corrosion inhibition Adsorption synergism

Can bedside needle arthroscopy of the ankle be an accurate option for intra-articular delivery of injectable agents?

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World Journal of Orthopedics 2022年第1期13卷 78-86页

作者： Tobias stornebrink sjoerd A s stufkens Nathaniel P mercer John G kennedy Gino m m J Kerkhoffs Department of Orthopedic surgery Amsterdam UMCUniversity of AmsterdamAmsterdam Movement SciencesAmsterdam 1105AZNetherlands Academic Center for Evidence based sports.m.dicine Amsterdam 1105AZNetherlands Amsterdam Collaboration for Health and safety in sports International Olympic Committee Research Center Amsterdam UMCAmsterdam 1105AZNetherlands Department of Orthopedic surgery NYU Langone HealthNew YorkNY 10010United States

BACKGROUND Bedside needle arthroscopy of the ankle under local anesthesia has been proposed for intra-articular delivery of injectable *** and tolerability of this approach in the clinical setting–including patients with end-stage ankle pathology and/or a history of prior surgery–is not *** To assess clinical accuracy and tolerability of bedside needle arthroscopy as a delivery system for injectable agents into the tibiotalar *** This was a prospective study that included adult patients who were scheduled for an injection with hyaluronic acid to the tibiotalar *** our center,these injections are used as a last resort prior to extensive *** primary outcome was injection accuracy,which was defined as injecting through the arthroscopic cannula with intra-articular positioning confirmed by a clear arthroscopic view of the joint *** outcome measures included a patientreported numeric rating scale(NRs,0-10)of pain during the procedure and willingness of patients to return for the s.m. *** of ankle pain at rest and during walking was collected at baseline and at 2-wk *** were monitored from inclusion up to a 2-wk control *** We performed 24 ***(46%)participants were male,and mean age was 46.8±14.5 *** was the indication for injection in 20(83%)cases,of which 8(33%)patients suffered from osteoarthritis Kellgren-Lawrence grade IV,and 10(42%)patients from Kellgren-Lawrence grade *** osteochondral defect was the indication for injection in 4(17%)cases.A history of ankle surgery was present in 14(58%)participants and a history of multiple ankle surgeries in 11(46%)*** was possible to confirm accuracy in 21(88%)*** 3(12%)participants where needle arthroscopy did not reach a clear view of the joint space all suffered from Kellgren-Lawrence grade IV *** during the procedure was reported with a median of 1[i

关键词： Ankle arthroscopy Nanoscope Needle arthroscopy Injections Proof of concept Patient experience

Relationship between the exocrine and endocrine pancreas after acute pancreatitis

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World Journal of Gastroenterology 2014年第45期20卷 17196-17205页

作者： stephanie L m Das James I C kennedy Rinki murphy Anthony R J Phillips John A Windsor maxim s Petrov Department of surgery University of Auckland Department of medicine University of Auckland

AIm: To determine the prevalence and time course of pancreatic exocrine insufficiency in individuals with newly diagnosed prediabetes or diabetes.m.llitus after acute pancreatitis.

关键词： Pancreatogenic diabetes Pancreatic exocrine insufficiency Acute pancreatitis Endocrine insufficiency

Genetic analyses of ancient tea trees provide insights into the breeding history and diss.m.nation of Chinese Ass.m.tea(Camellia sinensis ***)

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Plant Diversity 2024年第2期46卷 229-237页

作者： miao-miao Li muditha K.meegahakumbura moses C.Wambulwa Kevin s.Burgess.m.chael möller Zong-Fang shen De-Zhu Li Lian-ming Gao CAs Key Laboratory for Plant Diversity and Biogeography of East Asia Kunming Institute of BotanyChinese Academy of ScienceKunming650201China Germplasm Bank of Wild species Kunming Institute of BotanyChinese Academy of ScienceKunming650201China Kunming College of Life science University of Chinese Academy of SciencesKunming650201YunnanChina Department of Export Agriculture Faculty of Animal Science and Export AgricultureUva Wellassa UniversityBadulla90000Sri Lanka Department of Life sciences School of Science and ComputingSouth Eastern Kenya University170-90200KituiKenya Department of Biology Columbus State UniversityUniversity System of GeorgiaColumbusGA31907-5645USA Royal Botanic Garden Edinburgh 20A Inverleith RowEdinburghEH35LRScotlandUK Lijiang Forest Biodiversity National Observation and Research station Kunming Institute of BotanyChinese Academy of SciencesLijiang674100YunnanChina

Chinese Ass.m.tea(Camellia sinensis ***)is an important tea crop with a long history of cultivation in Yunnan,*** its potential value as a genetic resource,its genetic diversity and domestication/breeding history remain *** address this issue,we genotyped 469 ancient tea plant trees representing 26 *** *** populations,plus two of its wild relatives(six and three populations of *** and ***,respectively)using 16 nuclear microsatellite *** showed that Chinese Ass.m.tea has a relatively high,but comparatively lower gene diversity(H_(s)=0.638)than the wild relative ***(H_s=0.658).Clustering in sTRUCTURE indicated that Chinese Ass.m.tea and its two wild relatives formed distinct genetic groups,with considerable interspecific *** Chinese Ass.m.tea accessions clustered into three gene pools,corresponding well with their geographic ***,New Hybrids analysis indicated that 68.48%of ancient Chinese Ass.m.tea plants from Xishuangbanna were genetic intermediates between the Puer and Lincang gene *** addition,10%of the ancient Chinese Ass.m.tea individuals were found to be hybrids between Chinese Ass.m.tea and *** results suggest that Chinese Ass.m.tea was domesticated separately in three gene pools(Puer,Lincang and Xishuangbanna)in the mekong River valley and that the hybrids were subsequently selected during the domestication *** the domestication history of Chinese Ass.m.tea in southwestern Yunnan remains complex,our results will help to identify valuable genetic resources that may be useful in future tea breeding programs.

关键词： Tea plant Hybrid origin Genetic diversity Domestication history Camellia sinensis var.ass.m.ca Camellia taliensis