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Purification of Single-walled Carbon Nanotubes Grown by a Chemical Vapour Deposition(CVD) Method

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Chemical Research in Chinese Universities 2002年第2期18卷 130-132页

作者： Cigang Xu Emmanuel Flahaut Sam R.Bailey Gareth Brown Jeremy Sloan Karl S.Coleman VClifford Williams malcolm l.h.green Inorganic Chemistry laboratory University of OxfordOxfordOX13QRUK Department of Materials University of OrfordOxfordOX13PHUK

A procedure for purification of single walled carbon nanotubes(SWNTs) grown by the chemical vapour deposition(CVD) of carbon monooxide has been developed. Based on the result from TGA/DTA of as prepared sample, the oxidation temperature was determined. The process included sonication, oxidation and acid washing steps. The purity and yield after purification were determined and estimated by TEM. Moreover, for the first time, a loop structure for CVD SWNTs has been observed.

关键词： Single walled carbon nanotubes(SWNTs) Purification Chemical vapour deposition(CVD)

Synthesis and Characterization of WS_(2) Inorganic Nanotubes with Encapsulated/Intercalated CsI

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Nano Research 2010年第3期3卷 170-173页

作者： Sung You hong Ronit Popovitz-Biro Gerard Tobias Belén Ballesteros Benjamin G.Davis malcolm l.h.green Reshef Tenne Department of Chemistry Chemistry Research LaboratoryUniversity of OxfordMansfield RoadOxfordOX13TAUK Electron Microscopy Unit Weizmann Institute of ScienceRehovot 76100Israel Inorganic Chemistry laboratory University of OxfordSouth Parks RoadOxfordOX13QRUK Department of Materials and Interfaces Weizmann Institute of ScienceRehovot 76100Israel

WS2 nanotubes have been filled and intercalated by molten phase caesium *** presence of caesium iodide inside the WS_(2) nanotubes has been determined using high-resolution transmission electron microscopy(hRTEM)coupled with electron energy-loss spectroscopy(EElS)and energy-dispersive X-ray spectroscopy(EDS).Noticeably,a Moirépattern was observed due to the interference between encapsulated CsI and WS_(2) *** intercalation of CsI into the host concentric WS2 lattices resulted in an increase in the interplanar spacing.

关键词： Inorganic nanotubes transmission electron microscopy intercalation encapsulation

Methane Dry Reforming over Alumina Supported Co Catalysts

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Chemical Research in Chinese Universities 2004年第4期20卷 457-461页

作者： Sergio l. González Cortés malcolm l. h. green Inorganic Chemistry laboratory University of OxfordInorganic Chemistry Laboratory University of Oxford South Parks Road OX1 3QR UKSouth Parks Road OX1 3QR UK

A series of Co/γ-Al_2O_3 catalysts were prepared with the impregnation method and characterized by means of the BET specific surface area, X-ray diffraction(XRD), thermogravimetric analysis(TGA) and laser Raman spectroscopy. The Co/γ-Al_2O_3 catalysts were activated by using h_2, 20%Ch_4/h_2 or Ch_4, respectively. There was no obvious difference between the activities of the Co/γ-Al_2O_3 catalyst activated by using the different activation methods for methane dry reforming. The catalytic properties of the Co/γ-Al_2O_3 catalysts with different Co loadings were also investigated. The optimized Co loading for the Co/γ-Al_2O_3 catalyst pretreated with 20% Ch_4/h_2 is around 12%(mass fraction).

关键词： Methane dry reforming Alumina supported cobalt catalysts Catalytic deactivation

Tungsten Promoted Ni/Al_2O_3 Catalysts for Carbon Dioxide Reforming of Methane to Synthesis Gas

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Chemical Research in Chinese Universities 2004年第4期20卷 470-477页

作者： Thomas Suhartanto Andrew P. E. York malcolm l. h. green Wolfson Catalysis Centre Inorganic Chemistry Laboratory University of OxfordWolfson Catalysis Centre Inorganic Chemistry Laboratory University of OxfordWolfson Catalysis Centre Inorganic Chemistry Laboratory University of Oxford South Parks Road Oxford OX1 3QR UKSouth Parks Road Oxford OX1 3QR UKSouth Parks Road Oxford OX1 3QR UK

A series of tungsten promoted alumina supported nickel catalysts has been prepared for the carbon dioxide reforming of methane to synthesis gas. The catalysts have been characterized by means of XRD, TEM, and laser Raman spectroscopy. It is shown that the addition of tungsten to the nickel catalyst can stabilize the catalyst and increase the resistance to carbon deposition. Adding a suitable amount of tungsten can also increase the catalyst activity to be close to that of supported noble metal catalysts. The carburisation of the tungsten modified nickel catalyst decreases the catalyst activity at lower reaction temperatures(has no effect on the catalyst performance at higher reaction temperatures. The alumina supported nickel catalyst modified by 0.67%(mass fraction) WO_3 has the equivalent equilibrium constant of the dry reforming reaction to that of alumina supported 5%(mass fraction) Ru at 873 K, and also has a lower activation energy for dry reforming than the latter.

关键词： Nickel catalyst Tungsten modifier CO_2 reforming Methane Syngas

Silk-based nerve guidance conduits with macroscopic holes modulate the vascularization of regenerating rat sciatic nerve

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Neural Regeneration Research 2025年第6期20卷 1789-1800页

作者： Carina hromada Patrick heimel Markus Kerbl lászlóGál Sylvia Nürnberger Barbara Schaedl James Ferguson Nicole Swiadek Xavier Monforte Johannes C.heinzel Antal Nógrádi Andreas h.Teuschl-Woller David hercher Department life Science Engineering University of Applied Sciences Technikum WienViennaAustria Austrian Cluster for Tissue Regeneration ViennaAustria ludwig Boltzmann Institute for Traumatology The Research Center in Cooperation with AUVAViennaAustria University Clinic of Dentistry Medical University of ViennaViennaAustria Department of Plastic Reconstructive and Aesthetic SurgeryLandesklinikum Wiener Neustadt2700 Wiener NeustadtAustria Department of Anatomy Histology and EmbryologyAlbert Szent-Györgyi Medical SchoolUniversity of SzegedSzegedHungary Medical University of Vienna Department of Orthopedics and Trauma SurgeryDevision of Trauma SurgeryViennaAustria Department of hand- PlasticReconstructive and Burn SurgeryBG Unfallklinik TuebingenUniversity of TuebingenTuebingenGermany

Peripheral nerve injuries induce a severe motor and sensory deficit. Since the availability of autologous nerve transplants for nerve repair is very limited, alternative treatment strategies are sought, including the use of tubular nerve guidance conduits(tNGCs). however, the use of tNGCs results in poor functional recovery and central necrosis of the regenerating tissue, which limits their application to short nerve lesion defects(typically shorter than 3 cm). Given the importance of vascularization in nerve regeneration, we hypothesized that enabling the growth of blood vessels from the surrounding tissue into the regenerating nerve within the tNGC would help eliminate necrotic processes and lead to improved regeneration. In this study, we reported the application of macroscopic holes into the tubular walls of silk-based tNGCs and compared the various features of these improved silk^(+) tNGCs with the tubes without holes(silk^(–) tNGCs) and autologous nerve transplants in an 8-mm sciatic nerve defect in rats. Using a combination of micro-computed tomography and histological analyses, we were able to prove that the use of silk^(+) tNGCs induced the growth of blood vessels from the adjacent tissue to the intraluminal neovascular formation. A significantly higher number of blood vessels in the silk^(+) group was found compared with autologous nerve transplants and silk^(–), accompanied by improved axon regeneration at the distal coaptation point compared with the silk^(–) tNGCs at 7 weeks postoperatively. In the 15-mm(critical size) sciatic nerve defect model, we again observed a distinct ingrowth of blood vessels through the tubular walls of silk^(+) tNGCs, but without improved functional recovery at 12 weeks postoperatively. Our data proves that macroporous tNGCs increase the vascular supply of regenerating nerves and facilitate improved axonal regeneration in a short-defect model but not in a critical-size defect model. This study suggests that further optimizatio

关键词： axon regeneration blood vessel functional recovery macroporous nerve lesion peripheral nerve repair sciatic nerve silk-based nerve guidance conduit vascularization

Effect of Fe concentration on the nonlinear refraction and reverse saturable absorption in ferroelectric X-cut liNbO_3 crystal

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Chinese Optics letters 2015年第7期13卷 92-95页

作者： h.l.Saadon laser Applications and Optical Materials Group Department of Physics College of ScienceUniversity of Basrah

In this letter, the effects of the iron （Fe） dopant concentration on the nonlinear optical properties of iron-doped ferroelectric X-cut liNbO3 crystals plates are studied by using the Z-scan technique with a cw laser at the wave- length of 532 nm. The amount of iron in the compound is varied from 0 to 0.15 mol%. Measurements of nonlinear refractive index n2 and the nonlinear absorption coefficient β are determined. The sign of the nonlinear refractive index is found to be negative and the magnitude is on the order of 10-s cm2/W. This nonlinear effect increases as the concentration increases from 0 to 0.15 mol%. A good linear relationship is obtained between nonlinear refractive index, nonlinear absorption coefficient, and concentration.

关键词： Fe Effect of Fe concentration on the nonlinear refraction and reverse saturable absorption in ferroelectric X-cut liNbO3 crystal

Antihypertensive prescribing patterns in non-dialysis dependent chronic kidney disease:Findings from the Salford Kidney Study

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World Journal of Nephrology 2023年第5期12卷 168-181页

作者： Rajkumar Chinnadurai henry h l Wu Jones Abuomar Sharmilee Rengarajan David I New Darren green Philip A Kalra Donal O’Donoghue Renal Research Centre&Department of Renal Medicine Northern Care Alliance NHS Foundation TrustSalford M68HDUnited Kingdom Department of Renal Research Kolling Institute of Medical ResearchRoyal North Shore Hospital&The University of SydneySt.Leonards(Sydney)2065New South WalesAustralia Faculty of Biology Medicine&HealthThe University of ManchesterManchester M17HRUnited Kingdom

BACKGROUND hypertension is commonly observed in patients living with chronic kidney disease(CKD).Finding an optimal treatment regime remains challenging due to the complex bidirectional cause-and-effect relationship between hypertension and *** remains variability in antihypertensive treatment *** To analyze data from the Salford Kidney Study database in relation to antihypertensive prescribing patterns amongst CKD *** The Salford Kidney Study is an ongoing prospective study that has been recruiting CKD patients since *** patients are followed up annually,and their medical records including the list of medications are updated until they reach study endpoints[starting on renal replacement therapy or reaching estimated glomerular filtration rate(eGFR)expressed as ml/min/1.73 m2≤10 ml/min/1.73 m2,or the last follow-up date,or data lock on December 31,2021,or death].Data on antihypertensive prescription practices in correspondence to baseline eGFR,urine albumin-creatinine ratio,primary CKD aetiology,and cardiovascular disease were *** between patients who were prescribed three or more antihypertensive agents and their clinical outcomes were studied by Cox regression ***-Meier analysis demonstrated differences in survival *** Three thousand two hundred and thirty non-dialysis-dependent CKD patients with data collected between October 2002 and December 2019 were *** median age was 65 years.A greater proportion of patients were taking three or more antihypertensive agents with advancing CKD stages(53%of eGFR≤15 ml/min/1.73 m2 vs 26%of eGFR≥60 ml/min/1.73 m2,Plasses of antihypertensive agents was observed as the urine albumin-creatinine ratio category increased(category A3:62%vs category A1:40%,Ph the upward trends particularly noticeable in the number of individuals prescribed renin angiotensin system *** pr

关键词： hypertension Chronic kidney disease Antihypertensive agents Prescribing patterns Cardiovascular complications Renin angiotensin system blockers

land-walking ***-walking interventions in older adults:Effects on aerobic fitness

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Journal of Sport and health Science 2020年第3期9卷 274-282页

作者： Andrew haynes louise h.Naylor howard h.Carter Angela l.Spence Elisa Robey Kay l.Cox Barbara A.Maslen Nicola T.lautenschlager Nicola D.Ridgers Daniel J.green School of human Sciences(Exercise and Sport Science) The University of Western AustraliaPerthWA 6009Australia School of Physiotherapy and Exercise Science Curtin UniversityPerthWA 6102Australia School of Medicine The University of Western AustraliaPerthWA 6009Australia Academic Unit for Psychiatry of Old Age Department of PsychiatryThe University of MelbourneMelbourneVIC 3010Australia North Western Mental health Melbourne HealthMelbourneVIC 3010Australia Division of Psychiatry WA Centre for Health&AgeingThe University of Western AustraliaPerthWA 6009Australia Institute for Physical Activity and Nutrition(IPAN) School of Exercise and Nutrition SciencesDeakin UniversityGeelongVIC 3125Australia

Background:low cardiorespiratory fitness is an independent predictor of all-cause and cardiovascular mortality,and interventions that increase fitness reduce ***-walking decreases musculoskeletal impact and risk of falls in older individuals,but it is unclear whether water-walking improves aerobic fitness in the same way as weight-dependent *** randomized controlled trial involved 3 intervention groups—a no-exercise control group(CG),a land-walking(lW)group,and a water-walking(WW)group—to investigate the comparative impacts of lWandWWto CG on ***:Both exercise groups attended individually tailored,center-based,intensity-matched 3×weekly sessions for 24 weeks,which progressed to 150 min of exercise per *** was followed by a 24-week no-intervention *** graded exercise tests were performed on a treadmill at Weeks 0,24,and ***:Maximal oxygen uptake increased from Week 0 to Week 24 in both exercise groups(0.57±0.62 ml/kg/min,0.03±0.04 l/min for lW;0.93±0.75 ml/kg/min,0.06±0.06 l/min for WW,mean±SE)compared to the CG(-1.75±0.78 ml/kg/min,-0.16±0.05 l/min)(group×time,phaustion increased significantly following lW only(123.4±25.5 s),which was significantly greater(p=0.001)than the CG(24.3±18.5 s).By Week 48,the training-induced adaptations in the exercise groups returned to near baseline ***:Our study supports current physical-activity recommendations that 150 min/week of moderate-intensity exercise produces improvements in fitness in previously sedentary older ***,lW andWW elicit similar improvements in fitness if conducted at the same relative ***-na?ve older individuals can benefit from the lower impact forces and decreased risk of falls associated withWWwithout compromising improvements in cardiorespiratory fitness.

关键词： Cardiorespiratory fitness Graded exercise test Physical activity Water exercise

Three-dimensional dynamics of supported pipes conveying fluid

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Acta Mechanica Sinica 2017年第6期33卷 1065-1074页

作者： l.Wang T.l.Jiang h.l.Dai Department of Mechanics Huazhong University of Science and Technology Wuhan 430074 China hubei Key laboratory for Engineering Structural Analysis and Safety Assessment Wuhan 430074 China

This paper deals with the three-dimensional dynamics and postbuckling behavior of flexible supported pipes conveying fluid, considering flow velocities lower and higher than the critical value at which the buckling instability occurs. In the case of low flow velocity, the pipe is stable with a straight equilibrium position and the dynamics of the system can be examined using linear theory. When the flow velocity is beyond the critical value, any motions of the pipe could be around the postbuckling configuration(non-zero equilibrium position) rather than the straight equilibrium position, so nonlinear theory is required. The nonlinear equations of perturbed motions around the postbuckling configuration are derived and solved with the aid of Galerkin discretization. It is found, for a given flow velocity,that the first-mode frequency for in-plane motions is quite different from that for out-of-plane motions. however, the second-or third-mode frequencies for in-plane motions are approximately equal to their counterparts for out-of-plane motions, keeping almost constant values with increasing flow velocity. Moreover, the orientation angle of the postbuckling configuration plane for a buckled pipe can be significantly affected by initial conditions, displaying new features which have not been observed in the same pipe system factitiously supposed to deform in a single plane.

关键词： Pipe conveying fluid Three-dimensional dynamics Instability Natural frequency Postbuckling configuration