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POLAROGRAPHIC DETERMINATION OF PALLADIUM ION  [PDF]
V. Dumitrescu,Dana Popa,A. Tudorache
Analele Universitatii Bucuresti : Chimie , 2006,
Abstract: There was studied the polarographic behavior of palladium ion in presence of the reagent alpha - nitroso - beta - naphtol and the solvent hexamethylphosphotriamide (HMPA). The method can be used for quantitative determinations of palladium into the domain (0.5÷2.5) 10–4M. Polarograms were well defined and reproductible
POLAROGRAPHIC DETERMINATION OF Cd AND Te IN ELECTRODEPOSITED CdTe THIN FILMS
电沉积CdTe半导体薄膜中Cd和Te含量的极谱分析

GUO Yeping DENG Xunnan ZHANG Hongqing,
郭也平
,邓薰南,张红青

材料研究学报 , 1991,
Abstract: The variations on composition of electrodeposited CdTe thin films withcathodic potentials,electrolyte temperatures and heat treatment temperatures were studiedby using polarographic method.The CdTe thin films where the Cd/Te atomic ratio equalunity was ob
POLAROGRAPHIC DETERMINATION OF PALLADIUM ION IN PRESENCE OF α,α'- DIPYRIDYL AND HEXAMETHYLPHOSPHOTRIAMIDE  [PDF]
V. Dumitrescu,Oana-Lucia Terteleac
Analele Universitatii Bucuresti : Chimie , 2007,
Abstract: The polarographic behavior of palladium ion in the presence of α, α'- dipyridyl reagent and HMPA solvent was studied. The method can be used for quantitative determination of palladium into the domain 2 10–5 – 10–4 M. Polarograms were well defined and reproducible.
Effect of Hypotensive Resuscitation with a Novel Combination of Fluids in a Rabbit Model of Uncontrolled Hemorrhagic Shock  [PDF]
Yu-ming Zhang, Bo Gao, Juan-juan Wang, Xu-de Sun, Xi-wen Liu
PLOS ONE , 2013, DOI: 10.1371/journal.pone.0066916
Abstract: Objective The aim of this study was to compare the effects of hypotensive and normotensive resuscitation with a novel combination of fluids via lactate Ringer’s solution (LRS), 6% hydroxyethyl starch 130/0.4 solution (HES), and 7.5% hypertonic saline solution (HSS) at early stage of uncontrolled hemorrhagic shock (UHS) before hemostasis. Methods New Zealand white rabbits (n = 32) underwent UHS by transecting the splenic parenchyma, followed by blood withdrawal via the femoral artery to target mean arterial pressure (MAP) of 40–45 mmHg. Animals were distributed randomly into 4 groups (n = 8): in group Sham, sham operation was performed; in group HS, UHS was untreated; in group HS-HR, UHS was treated by hypotensive resuscitation with HSS and LRS+HES (ratio of 2:1) to MAP of 50–55 mmHg; in group HS-NR, UHS was treated by normotensive resuscitation with HSS and LRS+HES (ratio of 2:1) to MAP of 75–80 mmHg. Outcomes of hemodynamics, inflammatory and oxidative response, and other metabolic variables were measured and the histopathological studies of heart, lung and kidney were performed at the end of resusucitation. Results Hypotensive resuscitation with the novel combination of fluids for UHS rabbits decreased blood loss, maintained better stabilization of hemodynamics, and resulted in relatively higher hematocrit and platelet count, superior outcomes of blood gas, and lower plasma lactate concentration. Besides, hypotensive resuscitation attenuated the inflammatory and oxidative response significantly in UHS rabbits. Conclusion Hypotensive resuscitation with the novel combination of fluids via HSS and LRS+HES (ratio of 2:1) has an effective treatment at early stage of UHS before hemostasis.
POLAROGRAPHIC BEHAVIOR OF PALLADIUM ION IN PARTIAL AQUEOUS MEDIUMS  [PDF]
V. Dumitrescu,N. Dumitrescu,M. Calugareanu
Analele Universitatii Bucuresti : Chimie , 2005,
Abstract: There was studied the polarographic behavior of palladium ion in presence of thereagent 1,10-phenantroline and the solvent hexamethylphosphotriamide (HMPA). The methodcan be used for quantitative determinations of palladium into the domain 5·10-5 M-2·10-4 M.Polarograms were well defined and reproductible.
POLAROGRAPHIC BEHAVIOR OF PALLADIUM ION IN PARTIAL AQUEOUS MEDIUMS  [PDF]
V. Dumitrescu,Nina Dumitrescu,Dana Anghel
Analele Universitatii Bucuresti : Chimie , 2003,
Abstract: There was studied the polarographic behavior of palladium ion in presence of thereagent nitrosobenzene and the following solvents: hexamethylphosphortriamide (HMPA),dimethylphormamide (DMFA), dimethylsulfoxide (DMSO). The method can be used forquantitative determinations of palladium into the domain 5·10-5M-2·10-4M. Polarograms werewell defined and reproducible.
Determining the Effect of Cutting Fluids on Surface Roughness in Turning AISI 1330 Alloy Steel Using Taguchi Method  [PDF]
Onyemachi Joachim Onuoha, James Oseni Abu, Sunday Albert Lawal, Edeki Mudiare, Michael Bolaji Adeyemi
Modern Mechanical Engineering (MME) , 2016, DOI: 10.4236/mme.2016.62006
Abstract: Taguchi method has been employed to investigate the effects of cutting fluids on surface roughness in turning AISI 1330 alloy steel, using manually operated lathe machine. Experiments have been conducted using L27 (34) orthogonal array and each experiment was repeated three times and each test used a new cutting tool, High Speed Steel (HSS), to ensure accurate readings of the surface roughness. The statistical methods of Signal-to-Noise (S/N) ratio and the Analysis of Variance (ANOVA) were applied to investigate effects of cutting speed, feed rate and depth of cut on surface roughness under different cutting fluids. Minitab 14 software was used to analyze the effect of variables on the surface roughness. Results obtained indicated that optimal variables for the minimum surface roughness were cutting speed of 35 m/min (level 2), feed of 0.124 mm/rev (level 1), depth of cut of 0.3 mm (level 1) and a cutting fluid with a viscosity of 2.898 mm2/s (level 3). Hence, the optimal parameters to obtain better surface roughness of the workpiece material were obtained when groundnut oil based cutting fluid was used. Analysis of variance shows that feed rate has the most significant effect on surface roughness.
Polarographic and Spectrophotometric Study of Lead Complexes with Diethanoldithiocarbamate
Marques, A.L.B.;Chierice, G.O.;
Journal of the Brazilian Chemical Society , 1998, DOI: 10.1590/S0103-50531998000600005
Abstract: experimental and theoretical aspects concerning the behaviour of lead-dietanoldithiocarbamate complexes in aqueous solutions were studied. the reaction occurs through complexation and formation of a yellow precipitate, which is soluble in ligand excess and in some polar solvents. the results from elementary and gravimetric analyses show a stoichiometric relationship of 1:2 (pb(ii): dedc). some ambiguous interpretations have been clarified on the application in this system of lingane?s equation. polarographic measurements were used to determine the coordination number (@ 3.0) and overall formation constant bmln (@ 4 x 1016), of the lead complexes with ammonium diethanoldithiocarbamate, which show a good agreement with previous potentiometric results for the same system. a kinetic-spectrophotometric study was carried out in order to establish the decomposition of these complexes in acid medium.
Polarographic and Spectrophotometric Study of Lead Complexes with Diethanoldithiocarbamate  [cached]
Marques A.L.B.,Chierice G.O.
Journal of the Brazilian Chemical Society , 1998,
Abstract: Experimental and theoretical aspects concerning the behaviour of lead-dietanoldithiocarbamate complexes in aqueous solutions were studied. The reaction occurs through complexation and formation of a yellow precipitate, which is soluble in ligand excess and in some polar solvents. The results from elementary and gravimetric analyses show a stoichiometric relationship of 1:2 (Pb(II): DEDC). Some ambiguous interpretations have been clarified on the application in this system of Lingane?s equation. Polarographic measurements were used to determine the coordination number (@ 3.0) and overall formation constant betaMLn (@ 4 x 10(16)), of the lead complexes with ammonium diethanoldithiocarbamate, which show a good agreement with previous potentiometric results for the same system. A kinetic-spectrophotometric study was carried out in order to establish the decomposition of these complexes in acid medium.
Determining the viscous behavior of non-Newtonian fluids in a flume using a laminar sheet flow model and Ultrasonic Velocity Profiling (UVP) system
Haldenwang, Rainer;Kotzé, Reinhardt;Chhabra, Raj;
Journal of the Brazilian Society of Mechanical Sciences and Engineering , 2012, DOI: 10.1590/S1678-58782012000300008
Abstract: the flow of non-newtonian fluids in rectangular open channels has received renewed interest over the past number of years especially as large flumes are being used to transport tailings in countries like chile. the effect of yield stress on the flow behavior is complex and not yet fully understood. the ultrasonic velocity profiling (uvp) technique has been used to construct velocity profiles of non-newtonian fluids flowing in a 10 m by 300 mm wide tilting flume. the contour maps were integrated to show that the velocity profiles were indeed correct. the thin film flow models available in the literature have been tested in terms of flow depth and reynolds number. the measured profiles also show the influence of the side walls on the general flow features as the distance from the centre increases. the results reported herein span the laminar, transition and turbulent flow regions. as far as can be ascertained, it is the first time that this technique has been used to measure velocity profiles in opaque non-newtonian fluids for open channel flow. it is shown here that, under appropriate conditions, the velocity profile and flow depth can be used to obtain the viscous properties of the fluids tested. excellent correspondence between the rheological parameters inferred from the velocity profile measurements and that from the tube viscometry was obtained.
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