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Preparation and Characterisation of Corncob-Based Biosorbents in Côte d’Ivoire

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Advances in materials Physics and Chemistry 2024年第8期14卷 178-195页

作者： miezan Gnoan Ghislaine De Bouanzi Patrick Grah Atheba Serge Kouassi Gbamélé martin Alla Aka Albert Trokourey Laboratory of Constitution and Reaction of matter (LCRm) Flix Houphout-Boigny University Abidjan Cte dIvoire Laboratory of Environmental Sciences (LSE) Nangui Abrogoua University Abidjan Cte dIvoire

This study focuses on the preparation of corncob-based biosorbents. The chemical impregnation method was used to vary the chemical agent namely phosphoric acid H3PO4 (BA) and sodium hydroxide NaOH (BB). The physicochemical analysis of the two biosorbents indicated that under the same preparation conditions, the bio-sorbents have after activation yields lower than 50% (24.37% for BB and 49.09% for BA). In addition, the biosorbents have iodine index values between 444.17 mg/g and 418.79 mg/g and specific surfaces related to the adsorption of methylene blue ranging from 18.54 m2/g to 19.70 m2/g. The study of surface functional groups by using the Boehm test and pH zero point charge (pHPZC) confirmed the acidic nature of BA and BB biosorbents with respective values pHPZC = 4.01 and pHPZC = 4.90. The Langmuir method and BET analysis determined the specific surface areas by liquid phase adsorption of methylene blue as well as the porosity. The BET surface areas of BA and BB obtained are 72.01 m2/g and 63.10 m2/g respectively. The influence of the chemical activating agent on the formation of pores was confirmed by electron microscopy (SEm) analysis. From this study, it is found that the best activating agent for corn cobs was found to be phosphoric acid because the BA biosorbent was revealed to be the most favourable due to its surface area and good pore volume which are high compared to sodium hydroxide NaOH. moreover, their application as adsorbent for effluent treatment could be explored.

关键词： Biosorbent Corncobs Chemical Activation Phosphoric Acid Sodium Hydroxide

Supramolecular Single-Chain Polymeric Nanoparticles

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CCS Chemistry 2019年第1期1卷 64-82页

作者： gijs m.ter Huurne Anja R.A.Palmans E.W.meijer Institute for Complex molecular Systems Laboratory of Macromolecular and Organic ChemistryEindhoven University of TechnologyEindhoven 5600 MBThe Netherlands

Nature has unparalleled control over the conforma-tion and dynamics of its folded macromolecular ***’s ability to arrange amino acids into a precise spatial organization by way of folding allows proteins to fulfill s... 详细信息

关键词： folding polymers enzyme mimics supra-molecular polymer chemistry nanoparticle

Use of incipient motion data for backward erosion piping models

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International Journal of Sediment Research 2019年第5期34卷 401-408页

作者： Vera m.van Beek Bryant A.Robbins gijs J.C.m.Hoffmans Adam Bezuijen Leo C.van Rijn Deltares U.S.Army Engineer Research and Development Center Ghent University Leovanrijn-Sediment-Consultancy

Backward erosion piping involves the gradual removal of granular material under the action of water flow from the foundation of a dam or levee, whereby shallow pipes are formed that grow in the direction opposite to the flow. This pipe-forming process can ultimately lead to failure of a water-retaining structure and is considered one of the most important failure mechanisms for dikes and levees in the Netherlands and the United States. modeling of this mechanism requires the assessment of hydraulic conditions in the pipe, which are controlled by the particle equilibrium at the pipe wall. Since the pipe’s dimensions are controlled by the inflow to the pipe from the porous medium, the flow through the pipe is thought to be laminar for fine-to medium-grained sands. The literature provides data for incipient motion in laminar flow, which is reviewed here and complemented with data from backward erosion experiments. The experiments illustrate the applicability of the laminar incipient motion data to determine the erosion pipe dimensions and corresponding pipe hydraulics for fine-to medium-grained sands, for the purpose of backward erosion piping modeling.

关键词： Internal erosion Backward erosion piping Cylindrical test Incipient motion Dikes Levees

A LIOUVILLE THEOREm FOR STATIONARY INCOmPRESSIBLE FLUIDS OF VON mISES TYPE

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Acta mathematica Scientia 2019年第1期39卷 1-10页

作者： martin FUCHS Jan müLLER Fachbereich 6.1 mathematik Universit?t des Saarlandes

We consider entire solutions u of the equations describing the stationary flow of a generalized Newtonian fluid in 2 D concentrating on the question, if a Liouville-type result holds in the sense that the boundedness of u implies its constancy. A positive answer is true for p-fluids in the case p > 1(including the classical Navier-Stokes system for the choice p = 2), and recently we established this Liouville property for the Prandtl-Eyring fluid model,for which the dissipative potential has nearly linear growth. Here we finally discuss the case of perfectly plastic fluids whose flow is governed by a von mises-type stress-strain relation formally corresponding to the case p = 1. It turns out that, for dissipative potentials of linear growth, the condition of μ-ellipticity with exponent μ m.

关键词： generalized Newtonian fluids perfectly plastic fluids von mises flow Liouville theorem

morbidity and mortality of Acute Renal Failure in COVID-19 Patients in Intensive Care According to Waves/Variant: Case of the Grand Hôpital de l’Est Francilien Site de meaux

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Open Journal of Internal medicine 2024年第1期14卷 16-29页

作者： Khazy Anga Ariel makembi Éric Amisi Éric Delpierre Vivien Hong Tuan Ha Wilfrid mbombo Jean Claude mubenga Dan Kankonde Chris Nsituavibidila Lionel Diyamona Noelly mukuna Gracia Likinda Tharcisse mabiala martin mukenga médard Bula-Bula Berthe Barhayiga Département d’Anesthésie Réanimation Université de Kinshasa Kinshasa République démocratique du Congo Service de Réanimation Grand H&ocircpital de l’Est Francilien Meaux France Département de médecine Interne Université de Kinshasa Kinshasa République démocratique du Congo Service d’Anesthésie Réanimation Centre Hospitalier Monkole Kinshasa République démocratique du Congo Department of Anaesthesia and Intensive Care H&ocircpital Général de Référence de Kinshasa Kinshasa République démocratique du Congo Department of Anaesthesia and Intensive Care Université Protestante du Congo Kinshasa République démocratique du Congo

Introduction: The incidence of acute renal failure (ARF) varies between 20% and 40% of cases for COVID-19 patients admitted to the intensive care unit, with very high mortality, but heterogeneous according to the different epidemic waves, probably due to the genetic variant phenomenon of the virus. The aim of this study is to determine the morbidity and mortality of COVID-19 patients admitted with ARF to the intensive care unit of the Grand H?pital Est Francilien (GHEF) according to the waves and variants. methods: Cross-sectional observational study of COVID-19 patients with ARF admitted to the intensive care unit of the GHEF site in meaux covering the period from march 1st 2020 to December, 31st 2021. Per-hospitalisation and outcome data were collected and analysed with SPSS version 25.0 software using the Chi-square or Fischer’s exact test or Student’s t-test and logistic regression for p Results: A total of 86 patients were included. The mean age was higher (70 ± 8.5) in patients in the fourth wave than in the other waves (p = 0.015), with male predominance in all waves without significant difference. Co-morbidities: hypertension, diabetes, heart disease, dyslipidaemia and arrhythmia complete with fibrillation were present in all waves. The majority of patients were classified as KDIGO 1 for the different waves (1st: 61.9%, 2nd: 86.5%, 3rd: 80%, and 4th: 75%), with the same trend according to variant (alpha: 80%, beta: 75%, delta: 81.3%, omicron: 75%). mortality by the wave was: 1st: 28.5%, 2nd: 37.5%, 3rd: 23% and 4th: 11%) and by variant: alpha: 24.2%, beta: 44.8%, delta: 20.7%, omicron: 10.3%). Overall mortality was 33.7%. Case fatality was higher in the fourth wave. Hypertension, shock, failure to recover renal function, acute lung oedema, ventilator-associated lung disease and hyperkalaemia were factors associated with mortality (p Conclusion: Acute renal failure is common in COVID-19 patients admitted to the intensive care unit, and m

关键词： mortality COVID-19 morbidity Renal Failure Intensive Care Unit

Philippine retinoblastoma initiative multi-eye center study 2010-2020

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International Journal of Ophthalmology(English edition) 2024年第1期17卷 144-156页

作者： Roland Joseph D.Tan Gary John V.mercado Patricia E.Cabrera Paulita Pamela P.Astudillo Rolando Enrique D.Domingo Josept mari S.Poblete Charmaine Grace m.Cabebe Adriel Vincent R.Te melissa Anne S.Gonzales Jocelyn G.Sy Beltran Alexis A.Aclan Jayson T.So Fatima G.Regala Kimberley Amanda K.Comia Josemaria m.Castro mara Augustine S.Galang Aldous Dominic C.Cabanlas Benedicto Juan E.Aguilar Gabrielle S.Evangelista Jo michael maniwan Andrei P.martin Calvin Y.martinez John Alfred H.Lim Rena Ivy Bascuna Rachel m.Ng Kevin B.Agsaoay Kris Zanna A.Acluba-Arao Ellaine Rose V.Apostol Beatriz m.Prieto Department of Ophthalmology and Visual Sciences Philippine General HospitalManila 1000Philippines Department of Ophthalmology Baguio General Hospital and Medical CenterBaguio City 2600Philippines Department of Ophthalmology Manila Doctors HospitalManila 1000Philippines Department of Ophthalmology Rizal Medical CenterPasig City 1600Philippines Department of Ophthalmology Jose B.Lingad Memorial Regional HospitalPampanga 2000Philippines Department of Ophthalmology Southern Philippines Medical CenterDavao City 8000Philippines Department of Ophthalmology East Avenue Medical CenterQuezon City 1100Philippines Department of Ophthalmology Northern Mindanao Medical CenterCagayan de Oro City 9000Philippines Department of Ophthalmology Cebu Velez General HospitalCebu City 6000Philippines Legazpi Eye Center Legazpi City 4500Philippines Department of Ophthalmology Cagayan Valley Medical CenterTuguegarao City 3500Philippines

AIm:To provide a comprehensive and more representative national data on the disease,especially on treatment options and outcomes,and to determine access of retinoblastoma patients from Luzon,Visayas and mindanao to eye care,and determine if access is associated with delay in consultation,staging and ***:Cohort study of retinoblastoma patients seen in eleven institutions located in the three major areas of the Philippines namely Luzon,Vizayas and mindanao from ***:Totally 636 patients,involving 821 eyes,were ***(57%)were from Luzon and were seen in institutions in Luzon(72%).Annually,58±10 new cases were seen with 71%having unilateral *** delay of consultation remained long at 9(3,17)mo,longest in patients with unilateral disease(Pm the Visayas(Pma Staging System,only 35%of patients had Stage 1 while 47%already had extraocular *** was the most common treatment received by 484 patients while intravenous chemotherapy was received by *** were 250(39%)patients alive,195(31%)dead,85(13%)abandoned,17(3%)refused and 89(14%)with no ***:This study presents the largest cohort of retinoblastoma patients in the Philippines in terms of patients’and participating institutions’number and geographical location and type of institution(private and public).It also presents more comprehensive data on the treatments used and outcomes(survival,globe salvage,and vision retention rates).Delay in consultation was still long among patients leading to advanced disease stage and lower survival *** increasing capacity to diagnose and manage retinoblastoma in the country,the delay of consultation remains long primarily due to accessibility issues to eye care institutions especially in the Visayas and financial *** delay was still significant that overall survival rate remain low.

关键词： retinoblastoma Philippines clinical profile

Granulometry Assessment of Lom Pangar Dam Sediments (East-Cameroon)

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Journal of Geoscience and Environment Protection 2024年第6期12卷 207-231页

作者： Rodrigue Fotie Lele mihaela Amalia Diminescu Issoufou Ouedraogo Annette madelene Dăncila Souleymane Pelede Alphonse Emadak martin Lompo Department of Geology University Joseph Ki Zerbo Ouagadougou Burkina Faso Department of Water and Energy Green Heart International Bafoussam Cameroon Department of Hydraulic machineries and Environmental Engineering National University of Science and Technology Politehnica Bucharest Bucharest Romania Department of mining Engineering University Yembila-Abdoulaye-Toguyeni Fada NGourma Burkina Faso Department of Inorganic Chemistry University of Yaound I Yaound Cameroon

The Lom Pangar dam, the largest reservoir in Cameroon with a storage capacity of 6 km3 and a 30 mW hydropower plant, primarily regulates the hydrologic regime of the Sanaga River to maintain hydropower efficiency during dry seasons and enhance downstream hydropower plant performance. Understanding and managing sediments are crucial for the sustainability of dams, as indicated by numerous studies. This study assessed the granulometry of the sediments transported across the reservoir. For that purpose, 6 samples of fresh sediments were collected in the lacustrine and transitional sections of the reservoir using the standard method. Particles size was assessed using the laser diffusion technic after a 3 mm sieving. Various granulometric parameters were derived from the literature to analyze and characterize those sediments. Results show that silts are more than 70% of particles size and range between 2.19 - 60.26 µm. Size distribution also shows the same trend with D75 less than 51 µm. This is confirmed by the low values of Inman Skewness SkΦ (−0.168 to 0.303). The Sorting index S0 ranges from 0.31 to 0.53 µm, showing a very well-sorted sediments, aligning with low values of Krumbein index (0.906 - 1.683) that express the low heterometry of the particles. The consequence on the dam will be a quick clogging of the bottom of the reservoir. Their pH varies from 7.0 to 7.5. It also appears that the sandy fraction trend is higher in the right bank of the dam and reaches 22% on the right bank of Pangar River due to crystalline geology. Fraction greater than 3000 µm is negligible. The management of the dam has to keep attention to these results as siltation may close the safety outlet of the dam, damage turbines, and provoke recurrent technical and safety issues. Further, the clogging of the bottom of the reservoir may lead to an ecological problem with the limitation of hyporheic flow. Thus, water exchange with the underground water table and the natural purification of wate

关键词： Lom Pangar Dam Sediments Granulometry Sustainability Hydropower Dam Safety

Fluorescence quenching method for the determination of catechol with gold nanoparticles and tyrosinase hybrid system

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Chinese Chemical Letters 2010年第3期21卷 346-348页

作者： martin m.F.Choi Department of Chemistry Hong Kong Baptist University

The determination method of catechol by fluorescence quenching was *** assay was based on the combination of the unique property of gold nanoparticles with tyrosinase enzymatic *** the presence of tyrosinase,the fluorescence of gold nanoparticles was quenched by catechol which can be employed to detect *** the optimal conditions,a linear range 5.0×10^(-7)-1.0×10^(-3) mol L^(-1) and a detection limit 1.0×10^(-7) mol L^(-1) of catechol were obtained.o-Quinone intermediate produced...

关键词： Gold nanoparticles Tyrosinase Catechol Fluorescence quenching

Automating selective area electron diffraction phase identification using machine learning

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Journal of materiomics 2024年第4期10卷 896-905页

作者： m.mika N.Tomczak C.Finney J.Carter A.Aitkaliyeva Nuclear Engineering Program in Department of materials Science University of Florida100 Rhines HallGainesville32611FLUSA Department of materials Science&Engineering Case Western Reserve University2111 Martin Luther King Jr DrCleveland44106OHUSA

Selective area electron diffraction(SAED)patterns can provide valuable insight into the structure of a ***,the manual identification of collected patterns can be a significant bottleneck in the overall phase classification *** this work,we utilize the recent advances in computer vision and machine learning(mL)to automate the indexing of SAED *** performance of six different mL algorithms is demonstrated using metallic plutonium-zirconium *** most successful approach trained a neural network(NN)to make a classification of the phase and zone axis,and then utilized a second NN to synthesize multiple independent predictions of different tilts in a single sample to make an overall phase *** results demonstrate that automated SAED phase identification using mL is a viable route to accelerate materials characterization.

关键词： Selective area electron diffraction machine learning Phase identification metallic fuels Pu alloys