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Analysis of inhibition of concrete steel-rebar corrosion by Na_2Cr_2o_7 concentrations:Implications for conflicting reports on inhibitor effectiveness

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Journal of Central South University 2013年第12期20卷 3697-3714页

作者： J.o.okeniyi I.o.oladele I.J.Ambrose S.o.okpala o.M.omoniyi C.A.Loto A.P.I.Popoola Mechanical Engineering Department Covenant University Chemical Metallurgical and Materials Engineering Department Tshwane University of Technology

Corrosion test data were measured using non-destructive electrochemical techniques and analysed for studying inhibition effectiveness by different concentrations of NazCr207 on the corrosion of concrete steel-rehar in NaC1 and in H2So4 media. For these, specifications of ASTM G16-95 R04 were combined with the normal and the Gumbel probability density functions as model analytical methods for addressing issues of conflicting reports of inhibitor effectiveness that had generated concerns. Results show that reinforced concrete samples admixed with concentrations having 4 g （0.012 7 tool）, 8 g （0.025 4 mol） and 6 g （0.019 l tool） NaaCr207 exhibited, in that order, high inhibition effectiveness, with respective efficiency, r/, of （90.46±1.30）%, （88.41＋2.24）% and （84.87±4.74）%, in the NaC1 medium. These exhibit good agreements within replicates and statistical methods for the samples. Also, optimal inhibition effectiveness model in the H2So4 medium was exhibited by 8 g （0.025 4 mol） Na2Cr207 concentration having r/=（78.44±1.10）%. These bear implications for addressing conflicting test data in the study of effective inhibitors for mitigating steel-rebar corrosion in aggressive environments.

关键词： corrosion inhibitor effectiveness saline/marine and industrial/microbial environments concrete steel-rebar normal andGumbel probability distribution functions Kolmogorov-Smirnov statistics tests of significance

TIME AND NoRM oPTIMAL CoNTRoLS:A SURVEY oF RECENT RESULTS AND oPEN PRoBLEMS

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Acta Mathematica Scientia 2011年第6期31卷 2203-2218页

作者： H. o. Fattorini Department of Mathematics University of California Los Angeles

We present in this paper a survey of recent results on the relation between time and norm optimality for linear systems and the infinite dimensional version of Pontryagin＇s maximum principle. In particular, we discuss optimality （or nonoptimality） of singular controls satisfying the maximum principle and smoothness of the costate in function of smoothness of the target.

关键词： linear control systems in Banach spaces time optimal problem norm optimal problem

Photon energy absorption and exposure buildup factors for deep penetration in human tissues

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Nuclear Science and Techniques 2019年第12期30卷 31-39页

作者： o.Kadri A.Alfuraih Department of Radiological Sciences College of Applied Medical SciencesKing Saud UniversityPO Box 10219Riyadh 11433Saudi Arabia National Center for Nuclear Sciences and Technologies 2020 TunisTunisia

Using photons in therapeutic and diagnostic medicine requires accurate computation of their attenuation coefficients in human *** buildup factor,a multiplicative coefficient quantifying the ratio of scattered to primary photons,measures the degree of violation of the Beer-Lambert *** this study,the gamma-ray isotropic point source buildup factors,specifically,the energy absorption buildup factor(EABF)and exposure buildup factor,are *** computational methods used include the geometric progression fitting method and simulation using the Geant4(version 10.4)Monte Carlo simulation *** buildup factors of 30 human tissues were evaluated in an energy range of 0.015-15 MeV for penetration depths up to 100 mean free paths(mfp).At all penetration depths,it was observed that the EABF seems to be independent of the mfp at a photon energy of 1.5 MeV and also independent of the equivalent atomic number(Zeq)in the photon energy range of 1.5-15 ***,the buildup factors were inversely proportional to Zeq for energies below 1.5 ***,the Geant4 simulations of the EABF of water were in agreement with the available standard data.(The deviations were less than 5%.)The buildup factors evaluated in the present study could be useful for controlling human exposure to radiation.

关键词： Buildup factors Human tissues Geant4 GP fitting Gamma rays

Targeting the noradrenergic system for anti-inflammatory and neuroprotective effects: implications for Parkinson's disease

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Neural Regeneration Research 2018年第8期13卷 1332-1337页

作者： Eoin o'Neill Andrew Harkin Neuropsychopharmacology Research Group School of Pharmacy and Pharmaceutical Sciences & Trinity College Institute of Neuroscience Trinity College

Degeneration of the locus coeruleus noradrenergic system is thought to play a key role in the pathogenesis of Parkinson＇s disease （PD）, whereas pharmacological approaches to increase noradrenaline bioavailability may provide neuroprotection. Noradrenaline inhibits microglial activation and suppresses pro-inflamma- tory mediator production （e.g., tumor necrosis factor-a, interleukin-1β ＆ inducible nitric oxide synthase activity）, thus limiting the cytotoxicity of midbrain dopaminergic neurons in response to an inflamma- tory stimulus. Neighbouring astrocyte populations promote a neurotrophic environment in response to β2-adrenoceptor （β2-AR） stimulation via the production of growth factors （e.g., brain derived neurotrophic factor, cerebral dopamine neurotrophic factor ＆ glial cell derived neurotrophic factor which have shown promising neuroprotective and neuro-restorative effects in the nigrostriatal dopaminergic system. More recent findings have demonstrated a role for the β2-AR in down-regulating expression levels of the human a-synuclein gene SNCA and relative a-synuclein protein abundance. Given that a-synuclein is a major protein constituent of Lewy body pathology, a hallmark neuropathological feature in Parkinson＇s disease, these findings could open up new avenues for pharmacological intervention strategies aimed at alleviating the burden of a-synucleinopathies in the Parkinsonian brain. In essence, the literature reviewed herein supports our hypothesis of a tripartite neuroprotective role for noradrenaline in combating PD-related neuropathology and motor dysfunction via （1） inhibiting nigral microglial activation ＆ pro-inflammatory mediator production, （2） promoting the synthesis of neurotrophic factors from midbrain astrocytes and （3） downregulating a-synuclein gene expression and protein abundance in a β2-AR-dependent manner. Thus, taken together, either pharmacologically enhancing extra-synaptic noradrenaline bioavailability or targeting glial β2-ARs direct

关键词： noradrenaline microglia astrocytes inflammation Parkinson's disease neuroprotection animalmodel dopamie

Evaluation of the Quick Wee method of inducing faster clean catch urine collection in pre‑continent infants: a randomized controlled trial

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World Journal of Pediatrics 2022年第1期18卷 43-49页

作者： Aoife Branagan Niofa Canty Evanne o’Halloran Marian Madden Michael Brendan o’Neill Department of Paediatrics Mayo University HospitalCastlebarCo.MayoIreland

Introduction The acquisition of non-contaminated urine samples in pre-continent infants remains a *** Quick Wee method uses bladder stimulation to induce voiding.A previous randomized trial showed a higher rate of voiding within 5 minutes using this *** evaluated this method in an Irish hospital providing secondary *** A non-blinded,randomized,controlled trial was carried *** infants were between 1 and 12 months of age,who required urine sampling as part of clinical *** were randomly allocated to receive the intervention(Quick Wee Method—supra-pubic stimulation with cold saline)or the control(usual care—clean catch with no bladder stimulation)for 5 *** outcome was voiding of urine within 5 *** A total of 140 infants were included in this study(73 in intervention group;67 in control group).Baseline characteristics were similar.25%in the intervention group passed urine in the 5-min trial period compared with 18%in the control group[P=0.4,absolute diference 7%(95%confdence interval:−7%to+20%)].Conclusion The Quick Wee method is a simple and inexpensive intervention that did not show a statistically signifcant increase in urine samples obtained in pre-continent infants.

关键词： Infant Urinalysis Urinary tract infection Urine specimen collection

Two-Stage Robust optimization Under Decision Dependent Uncertainty

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IEEE/CAA Journal of Automatica Sinica 2022年第7期9卷 1295-1306页

作者： Yunfan Zhang Feng Liu Yifan Su Yue Chen Zhaojian Wang João P.S.Catalão State Key Laboratory of Power System and Generation Equipment the Department of Electrical EngineeringTsinghua UniversityBeijing 100084China Department of Mechanical and Automation Engineering the Chinese University of Hong KongHong Kong SARChina Ministry of Education Key Laboratory of System Control and Information Processing the Department of AutomationShanghai Jiao Tong Universityand also with Shanghai Engineering Research Center of Intelligent Control and ManagementShanghai 200240China Faculty of Engineering of the University of Porto and Institute for Systems and Computer Engineering Technology and Science(INESC TEC)Porto 4200-465Portugal IEEE

In the conventional robust optimization(Ro)context,the uncertainty is regarded as residing in a predetermined and fixed uncertainty *** many applications,however,uncertainties are affected by decisions,making the current Ro framework *** paper investigates a class of two-stage Ro problems that involve decision-dependent *** introduce a class of polyhedral uncertainty sets whose right-hand-side vector has a dependency on the here-and-now decisions and seek to derive the exact optimal wait-and-see decisions for the second-stage problem.A novel iterative algorithm based on the Benders dual decomposition is proposed where advanced optimality cuts and feasibility cuts are designed to incorporate the uncertainty-decision *** computational tractability,robust feasibility and optimality,and convergence performance of the proposed algorithm are guaranteed with theoretical *** motivating application examples that feature the decision-dependent uncertainties are ***,the proposed solution methodology is verified by conducting case studies on the pre-disaster highway investment problem.

关键词： Benders decomposition decision-dependent uncertainty endogenous uncertainty robust optimization(Ro)

Burden of disability in type 2 diabetes mellitus and the moderating effects of physical activity

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World Journal of Clinical Cases 2023年第14期11卷 3128-3139页

作者： olufemi o oyewole Ayotunde o Ale Michael o ogunlana Thavanesi Gurayah Department of Physiotherapy Olabisi Onabanjo University Teaching HospitalSagamu 201101OgunNigeria College of Health Sciences University of KwaZulu-NatalDurban 3629South Africa Department of Medicine Olabisi Onabanjo UniversitySagamu 121101OgunNigeria Department of Endocrinology Diabetes and Metabolism UnitMedicineOlabisi Onabanjo University Teaching HospitalSagamu 121101OgunNigeria Department of Physiotherapy Federal Medical CentreAbeokuta 110101OgunNigeria occupational Therapy School of Health SciencesUniversity of Kwazulu NatalPrivate Bag X54001Durban4000

The growing diabetic epidemic has created a substantial burden,not only on the people with diabetes but also on society at *** mini-review discussed the limitations and patterns of disability in type 2 diabetes mellitus and put forward a case for the moderating effects of physical activity(PA)in the management of *** limitations and impairments associated with diabetes include vascular,neurological,cardiac,and renal ***,individuals participate less in their daily lives and in their instrumental activities of daily living,which negatively impacts the quality of life of individuals with *** often leads to a loss of quality of life due to disabilities,resulting in an increased rate of disability-adjusted life years among people with type 2 diabetes ***,there are psychosocial sequelae of diabetes *** necessitates looking for moderating factors that may reduce the burden of the *** has been shown to be one of the factors that can mitigate these *** does this in several ways,including through the benefits it confers,such as a reduction of hemoglobin A1c,a reduction of excess fat in the liver and pancreas,and the reduction of cardiovascular risk factors,all of which favorably affect glycemic ***,PA regulates or moderates diabetes disability through two mechanisms:The regulation of glucolipid metabolism disorders and the optimization of body mass index and systemic ***,efforts should be directed at PA uptake through identified *** will not only prevent diabetes or diabetes complications but will reduce its burden.

关键词： Type 2 diabetes mellitus Disability burden Physical activity Moderating effect

Structural and superconducting properties in Y_(0.6)Gd_(0.4)Ba_2(Nb)Cu_3o_(7-y) cuprates doped with niobium

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Journal of Rare Earths 2012年第3期30卷 241-244页

作者： M. Yilmaz o. Dogan A. K. Education Faculty Department of Physics Konya University

Polycrystalline YBa2Cu3o7-y （YBCo） and Y0.6Gd0.4Ba2-xNbxCu3o7-y （YGBNCo） compounds with 0≤x≤0.225 were synthesized using standard solid state reaction technique. The structure for all samples was characterized by X-ray difference （XRD） and scanning electron microscopy （SEM）. The transport properties were measured by the （FPP） method in the temperature range from 70 to 130 K. As the Nb content in the samples increased, a diffused phase indicating a niobium perovskite phase and a small amount of unidentified phase appeared. With the increase of Nb content, the superconducting transition temperature Tconset increased slowly with x≤0.125, and then it remained unchanged or slowly decreased with 0.125≤x≤0.225. It could be found that there was a slow decrease of zero-resistance temperature, Tcoffset, with the increase of Nb content. The larger transition width might result from the YBa2Nbo6 phase, impurity and unidentified phases of the sample due to the Nb doping.

关键词： Y0.6Gd0.4Ba2Cu3o7-y cuprates Gd and Nb co-doping structural and superconducting properties rare earths

Extraction of niobium from sulfate leach liquor of Egyptian ore sample by triazoloquinazolinone

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中国有色金属学会会刊：英文版 2009年第2期19卷 474-478页

作者： o. M. EL HUSSAINI Nuclear Materials Authority P.O. Box 530 El MaadiCairoEgypt

The refractory niobium bearing minerals,Samarskite,Fergusonite,Betafite and Pyrochlore of the ore sample obtained from Kadabora,Egypt,was subjected to sulfuric acid leaching using acid concentrations varied from 17.6 to 4.5 mol/ L. The extraction of niobium from the sulfate leach liquors was done using the synthesized 8,9-dihydro[1,2,4]triazolo[1,5-a]quinazolin6(7H)-one dissolved in methylene chloride. It has been found that extraction efficiency of 84% was achieved by contacting equal volumes of 0.32% extractant with 4.5 mol/L sulfate solution for 15 min. The stripping was performed by 0.5 mol/L HF with efficiency of 86.7%.

关键词：硫酸浸出液矿石样品提取效率铌矿物埃及使用浓度二氯甲烷硫酸溶液