Artículos de revistas: "Titration"

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Fuhrmann, B. y U. Spohn. "A PC-based titrator for flow gradient titrations". Journal of Automatic Chemistry 15, n.º 6 (1993): 209–16. http://dx.doi.org/10.1155/s1463924693000276.

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This paper describes a PC (personal computer) based titrator which was developed for gradient flow titrations. Concentration gradients were generated electrolytically or volumetrically in small tubes. Complete titration curves can be recorded on-line and evaluated automatically. The titrator can be used with all liquid flow detectors with low axial dispersion. The titrator was evaluated for the titration of thiosulphate with electrogenerated triiodide and for the titration of ammonia with electrogenerated hypobromite after continuous gas dialytic separation of ammonia from the sample solution.

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FERNANDEZ-MAESTRE, Roberto. "THE IMPORTANCE OF TEACHING TITRATION CURVES IN ANALYTICAL CHEMISTRY". Periódico Tchê Química 17, n.º 34 (20 de marzo de 2020): 213–19. http://dx.doi.org/10.52571/ptq.v17.n34.2020.230_p34_pgs_213_219.pdf.

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Titration curves are an essential subject of an Analytical Chemistry course. The main objective of calculating titration curves is the selection of an indicator for such titrations. The calculation of titration errors is imperative because they establish if a given indicator can be used for a given titration. This study reviews the available literature on titration curves and calculating their errors. Its purpose is to draw attention to the importance of undergraduate chemistry students having competencies to determine the titration errors rather than skills to build titration curves as the ultimate purpose of these curves is to determine the failure committed when using a given indicator to assess their endpoints. It is shown that the pH and potential calculation at the equivalence point in acid-base and redox titrations, respectively, are not required to choose the titration indicator, one that yields an acceptable error according to the type of application needed. Methods to calculate these errors in the four main types of titrations are presented; those for complexometric and precipitation titrations are simpler than in the literature. Here, it is also demonstrated that calculating points immediately after and before the curve inflection are more critical for this selection in these two types of titrations. Also, it is deducted that complexometric and precipitation curves are not required to select indicators for these titrations. These demonstrations are essential because analytical chemistry teachers may disregard teaching important topics by spending time calculating unnecessary titration curves (complexometric and precipitation titrations) or additional points of titration curves (redox and acid-base titrations) when the calculation of titration errors of these reactions is more critical. Most analytical chemistry textbooks neglect this topic. Undergraduate chemistry programs should focus more on calculating titration errors than on the construction of titration curves.

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Ayoub, Muhammad Haris, Shehryar Ahmad, Zia Ul Hassan, Asad Muhammad Khan, Muhammad Bilal, Amir Waseem y Ahson Jabbar Shaikh. "Understanding non-covalent interactions of graphene oxide toward transition metal surfaces and relation of binding constants with titration end points from dynamic light scattering studies". Journal of Applied Physics 133, n.º 2 (14 de enero de 2023): 025303. http://dx.doi.org/10.1063/5.0134267.

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The understanding of non-covalent binding interactions of graphene oxide toward transition metal surfaces (Fe, Co, Ni, and Cu) was observed by ultraviolet–visible absorption spectroscopy, fluorescence emission spectroscopy, hydrodynamic size, and zeta potential studies through titration experiments. These interactions mainly occur through C=C double bonds of graphene oxide. Iron and cobalt nanoparticles interact strongly as compared to nickel and copper nanoparticles. The obtained Stern–Volmer plots are curved indicating that static and dynamic quenching occur simultaneously in these systems. The curves obtained for size titration graphs indicated the saturation end point for these titrations, which were then compared with binding constants obtained from linear Stern–Volmer plots. Interestingly, with lower binding constants, a higher concentration of nanoparticles was required for titration end points. These two complimentary techniques stood well quantitatively toward each other. Upon titrating the nanoparticles with graphene oxide, the zeta potential always lowered close to the value of graphene oxide, indicating that hybrids are more stable than the nanoparticles.

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Feitkenhauer, H. y U. Meyer. "On-line titration of non-ionic surfactants in wastewater treatment plants using a specific electrode". Water Science and Technology 45, n.º 4-5 (1 de febrero de 2002): 61–68. http://dx.doi.org/10.2166/wst.2002.0552.

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Textile finishing industry wastewater often contains high concentrations of surfactants. Non-ionic surfactants like alcohol ethoxylates are among the most used surfactants and are discharged from batch-processes in widely varying concentrations. The anaerobic biomass and especially methanogenic microorganisms have been shown to be inhibited by surfactants. To protect these microorganisms from irreversible inhibition a measurement of the surfactant concentration is useful for the process control, but most analytical methods are too complicated and expensive for an on-line process control. It was shown that the titration of non-ionic surfactants is possible in the presence of biomass and in wastewater from textile wet processes using the Metrohm NIO-electrode. Titration and sampling were successfully performed with standard equipment. The software used for the process control of a lab-scale anaerobic treatment plant was also used to evaluate the obtained titration curves. This allowed performing the titrations without using a more expensive titrator.

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Gibson, Graham, Alexei A. Neverov y R. S. Brown. "Potentiometric titration of metal ions in methanol". Canadian Journal of Chemistry 81, n.º 6 (1 de junio de 2003): 495–504. http://dx.doi.org/10.1139/v03-035.

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The potentiometric titrations of nine lanthanideIII triflates, ZnII and CuII triflate, and the NiII, CoII, MgII, and TiIV perchlorates were obtained in methanol to determine the titration constants (defined as the sspH at which the [OCH3]/[Mx+]t ratios are 0.5 and 1.5) as well as the apparent sspKa values for deprotonation of the metal-bound solvent molecules. The titrations were performed under various conditions with and without added salts as electrolytes, and the variations in the titration constants are discussed. In selected cases (La3+, Zn2+) the titration profiles were analyzed using a complex fitting program to obtain information about the species present in solution.Key words: potentiometric titration, methanol, sspH, metal ion, lanthanides, apparent sspKa.

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Gonzalez, G. G., A. M. Jimenez y A. G. Asuero. "Titration errors in acid-base titrations". Microchemical Journal 41, n.º 1 (febrero de 1990): 113–20. http://dx.doi.org/10.1016/0026-265x(90)90103-c.

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7

Bodiroga, Milanka y Jasminka Ognjanovic. "Determination of peracetic acid and hydrogen peroxide in the mixture". Vojnosanitetski pregled 59, n.º 3 (2002): 277–79. http://dx.doi.org/10.2298/vsp0203277b.

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Iodometric and permanganometric titrations were used for determination of peracetic acid and hydrogen peroxide (H2O2) in the mixture. Two procedures were described and compared. Titrations could be done in only one vessel, in the same reaction mixture, when iodometric titration of peracetic acid was continued after the permanganometric titration of H2O2, (procedure A). Peracetic acid and H2O2, as oxidizing agents, reacted with potassium iodide in an acid medium, evolving iodine. This reaction was used for the quantitative iodometric determination of total peroxide in procedure B. H2O2 reacted with potassium permanganate in acid medium, but peracetic acid did not react under the same conditions. That made possible the selective permanganometric determination of H2O2 in the presence of peracetic acid. The procedure B was performed in two titration vessels (KV=3.4% for peracetic acid, 0.6% for H2O2). The procedure A for iodometric determination of peracetic acid in one titration vessel after permanganometric titration of H2O2 was recommended (KV=2,5% for peracetic acid, 0,45% for H2O2).

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Bhavya sri Khagga, Srija Ghanukota y Sumakanth Mogili. "Novel titrimetric method for the determination of rosuvastatin in pure form". World Journal of Biology Pharmacy and Health Sciences 13, n.º 2 (28 de febrero de 2023): 001–4. http://dx.doi.org/10.30574/wjbphs.2023.13.2.0054.

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In this experiment assay of Rosuvastatin was performed by titrimetric method. The titration performed is a complexometric titration. The complexometric titration used is an easy, inexpensive volumetric titration method. This method is based on rection of calcium with a solution of disodium ethylenediaminotetraacetate (EDTA). Complex of calcium and EDTA is formed. Erichrome black Tis used as an indicator in this complexometric titration. At pH 12-13, Erichrome black T changes the color from pink to blue. The appearance blue color is determined to be the endpoint of this experiment. The titrations were carried out in triplicates and the average reading was taken to calculate the percentage assay. The percentage purity was found to be 103.05%

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DiMaria, Michelle, Brian Schultz, Jennifer Falvo, Edward Matthews, Michelle Ward, Jordan Land, Danna Tauber y Suzanne Beck. "0502 Harmony in the Sleep Lab: A Focus on Recognition of Hypoventilation and Direct Feedback Improves Quality of Pediatric Titrations". Sleep 45, Supplement_1 (25 de mayo de 2022): A222. http://dx.doi.org/10.1093/sleep/zsac079.499.

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Abstract Introduction Over 350 pediatric polysomnogram titrations (T-PSGs) are performed each year at the Sleep Laboratory at Children’s Hospital of Philadelphia in three locations by 24 different polysomnography technologists (PSGTs) on a diverse patient population, typically performed as outpatient procedures and occasionally at the bedside as inpatients. PSGTs are responsible for titration of continuous or bilevel positive airway pressure based on flow, work of breathing, arousals, and/or gas exchange. PSGTs have varying degrees of experience; thus, maintaining quality of T-PSGs is challenging. We hypothesized that a quality improvement (QI) approach to reviewing T-PSGs with interdisciplinary education and regular feedback would improve T-PSGs. Our goal was to have >/= 80% of titrations of optimal quality. Methods Each T-PSG record was reviewed by a sleep physician for optimal quality, defined as appropriate signal integrity, titration, and documentation to permit definitive interpretation. Exclusion: RAM cannula use, illness, or external signal interference. Titration QI (T-QI) comments were reviewed by the sleep lab QI team bi-weekly to plan feedback. Improvement interventions for PSGTs included didactic education: lectures, presentations, and cases focusing on recognition of hypoventilation; direct feedback with teaching points by sleep physician and small group sessions with clinical supervisors to review areas for improvement; and communication of specific titration goals. Satisfaction surveys regarding recognition/titration for OSA/hypoventilation, transcutaneous CO2 signal integrity, and documentation were administered to sleep physicians. Results From September 2020-November 2021, PSGT education included: 1 synchronous and 2 asynchronous didactic presentations; 1:1 review of didactics with each night PSGT (n=24); T-QI feedback (2/week); and small group review sessions (4/week). 408 titrations were completed; 42 (10.3%, 2.8/month) were excluded; 366 (89.7%, 24.4/month) were reviewed for T-QI. 54.8% [50,71%] were deemed optimal during the first three months (pre-intervention) vs. 80.1% [63,96%] during the intervention period. QI satisfaction survey showed improvement in 3 of 4 domains. Conclusion Quality of T-PSG is enhanced by QI review of each titration, highlighting teaching points and areas for improvement via direct feedback and small group review. Education and communication among physicians, supervisors and technologists are important to support development which can result in better titrations and satisfaction. Support (If Any) none

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10

Besenhard, J. O., H. P. Gansmann y H. Meyer. "Bestimmung von Oberflächenoxiden auf Rußen durch potentiometrische Direkttitration in nichtwäßrigen Lösungsmitteln / Determination of Surface Oxides on Carbon Blacks by Direct Potentiometric Titration in Non-Aqueous Solvents". Zeitschrift für Naturforschung B 45, n.º 6 (1 de junio de 1990): 857–63. http://dx.doi.org/10.1515/znb-1990-0617.

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An attempt is made to quantitatively determine acidic and basic surface oxides on carbon blacks and also to monitor their acid and base strength distribution by direct potentiometric titrations in non-aqueous media.In contrast to direct titration procedures proposed so far, our method allows to distinguish clearly between several types of acidic surface oxides of different acid strength. This is mainly achieved by improvements of the non-aqueous titration media. The total contents of weakly and strongly acidic and also of basic oxides determined by this very fast method is comparable to results obtained by slow and laborious indirect titrations.

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Morák, M. y Ústi nad Labem. "Titration von Alkylammoniumsalzen / Titrations of Alkyl Ammonium Salts". Tenside Surfactants Detergents 26, n.º 3 (1 de mayo de 1989): 215–21. http://dx.doi.org/10.1515/tsd-1989-260316.

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Ramette, Richard W. "Gravimetric Titrations: In Support of Weight Titration Techniques". Journal of Chemical Education 81, n.º 12 (diciembre de 2004): 1715. http://dx.doi.org/10.1021/ed081p1715.2.

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13

Price, Randi y Ping Wan. "Determination of Quaternary Ammonium Compounds by Potentiometric Titration with an Ionic Surfactant Electrode: Single-Laboratory Validation". Journal of AOAC INTERNATIONAL 93, n.º 5 (1 de septiembre de 2010): 1542–52. http://dx.doi.org/10.1093/jaoac/93.5.1542.

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Abstract A potentiometric titration for determining the quaternary ammonium compounds (QAC) commonly found in antimicrobial products was validated by a single laboratory. Traditionally, QACs were determined by using a biphasic (chloroform and water) manual titration procedure. Because of safety considerations regarding chloroform, as well as the subjectivity of color indicator-based manual titration determinations, an automatic potentiometric titration procedure was tested with quaternary nitrogen product formulations. By using the Metrohm Titrando system coupled with an ionic surfactant electrode and an Ag/AgCl reference electrode, titrations were performed with various QAC-containing formulation products/matrixes; a standard sodium lauryl sulfate solution was used as the titrant. Results for the products tested are sufficiently reproducible and accurate for the purpose of regulatory product enforcement. The robustness of the method was measured by varying pH levels, as well as by comparing buffered versus unbuffered titration systems. A quantitation range of 11000 ppm quaternary nitrogen was established. Eight commercially available antimicrobial products covering a variety of matrixes were assayed; the results obtained were comparable to those obtained by the manual titration method. Recoveries of 94 to 104% were obtained for spiked samples.

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Al-Ghannam, Sheikha M., Abdalla M. S. Abulkibash y Abeer M. Al-Olyyan. "Differential Electrolytic Potentiometric Determination of Some Amino Acids in Dosage Forms". Journal of AOAC INTERNATIONAL 87, n.º 3 (1 de mayo de 2004): 671–76. http://dx.doi.org/10.1093/jaoac/87.3.671.

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Abstract The application of direct-current differential electrolytic potentiometry to the nonaqueous titration of amino acids was investigated. The basic character of amino acids in acetic acid was enhanced to permit their direct titration with perchloric acid. A pair of antimony electrodes was used as an indicating system. The shapes of the titration curves obtained were almost symmetrical with sharp peaks. The optimum current density for those titrations was found to be 1–2 μA/cm2. The procedure was applied successfully to the determination of certain amino acids in drug formulations, and the results were favorably compared statistically with those obtained by official methods.

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Cavalcanti, Bernadete F., Lourdes Cristina Lucena Agostinho y Luciano Nascimento. "DETERMINATION OF ALKALINITY AND DISSOCIATION CONSTANTS OF HIGH SALINITY WATERS: USE OF F5BC TITRATION FUNCTION". Eclética Química Journal 35, n.º 2 (16 de enero de 2018): 79. http://dx.doi.org/10.26850/1678-4618eqj.v35.2.2010.p79-87.

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Measurements of parameters expressed in terms of carbonic species such as Alkalinity and Acidity of saline waters do not analyze the influence of external parameters to the titration such as Total free and associated Carbonic Species Concentration, activity coefficient, ion pairing formation and Residual Liquid Junction Potential in pH measurements. This paper shows the development of F5BC titration function based on the titrations developed by Gran (1952) for the carbonate system of natural waters. For practical use, samples of saline watersfrom Pocinhos reservoir in Paraiba were submitted to titration and linear regression analysis. Results showed that F5BC involves F1x and F2x Gran functions determination, respectively, for Alkalinity and Acidity calculations without knowing “a priori” the endpoint of the titration. F5BC also allows the determination of the First and Second Apparent Dissociation Constant of the carbonate system of saline and high ionic strength waters.

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Gündüz, Turgut, Esma Kiliç, Güleren Özkan, Muhammed F. Awaad y Mustafa Tastekin. "Conductimetric and potentiometric investigation of effect of acidity on formation of homoconjugates in acetonitrile solvent". Canadian Journal of Chemistry 68, n.º 5 (1 de mayo de 1990): 674–78. http://dx.doi.org/10.1139/v90-103.

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In the present work, 11 aromatic and nine aliphatic carboxylic acids, namely benzoic, 2-nitrobenzoic, 3-nitrobenzoic, 4-nitrobenzoic, 2,4-dinitrobenzoic, 3,5-dinitrobenzoic, 2-aminobenzoic, 3-aminobenzoic, 4-aminobenzoic, o-phthalic, salicylic, formic, acetic, monochloroacetic, dichloroacetic, trichloroacetic, propionic, n-butyric, caprylic, and myristic acids, were titrated conductimetrically and potentiometrically with triethylamine in acetonitrile solvent, under a nitrogen atmosphere, at 25 °C. Closer investigation of the conductimetric titration curves of these acids showed that the acidity of an acid, rather than the basicity of its conjugate base, plays a major part in the formation of homoconjugate ions, at least in acetonitrile solvent. If the acid is strong enough, there is a maximum before the experimental end point at about the half-neutralization point. To determine the minimum strength for an acid to show this maximum before the end point, all acids were also titrated potentiometrically. It was found that those acids which have half-neutralization potentials over −85 mV give a strong homoconjugation reaction and show a maximum before the experimental end point. Moreover, the acids that show maxima before the experimental end point in the conductimetric titration also show rather well-shaped potentiometric titration curves. Keywords: nonaqueous media, conductimetric titrations, potentiometric titrations, titration in acetonitrile, acidity and homoconjugation.

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Cavalcanti, B. F., L. C. L. Agostinho y L. Nascimento. "Determination of Alkalinity and dissociation constants of high salinity waters: use of F5BC titration function". Eclética Química 35, n.º 2 (2010): 79–87. http://dx.doi.org/10.1590/s0100-46702010000200009.

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Measurements of parameters expressed in terms of carbonic species such as Alkalinity and Acidity of saline waters do not analyze the influence of external parameters to the titration such as Total free and associated Carbonic Species Concentration, activity coefficient, ion pairing formation and Residual Liquid Junction Potential in pH measurements. This paper shows the development of F5BC titration function based on the titrations developed by Gran (1952) for the carbonate system of natural waters. For practical use, samples of saline waters from Pocinhos reservoir in Paraiba were submitted to titration and linear regression analysis. Results showed that F5BC involves F1x and F2x Gran functions determination, respectively, for Alkalinity and Acidity calculations without knowing "a priori" the endpoint of the titration. F5BC also allows the determination of the First and Second Apparent Dissociation Constant of the carbonate system of saline and high ionic strength waters.

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18

Peng, Victor, Nauras Hwig, Anayansi Lasso-Pirot, Amal Isaiah y Montserrat Diaz-Abad. "0529 Average volume-assured pressure support as rescue therapy after CPAP failure in pediatric obstructive sleep apnea". Sleep 45, Supplement_1 (25 de mayo de 2022): A233. http://dx.doi.org/10.1093/sleep/zsac079.526.

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Abstract Introduction Average volume-assured pressure support with autotitrating EPAP (AVAPS-AE) is an automatically titrating mode of noninvasive ventilation (NIV) which provides a targeted tidal volume through adjustment of inspiratory pressures within a set range. In pediatric obstructive sleep apnea (OSA), adenotonsillectomy (AT) is often the first-line treatment and CPAP is often poorly tolerated as an alternative. We aimed to evaluate the efficacy of AVAPS as a potential option for children in whom CPAP titration is unsuccessful. Methods Retrospective review of records of children diagnosed with OSA with failed CPAP titration and in whom an in-laboratory AVAPS titration was performed. Results A total of 9 patients with OSA (8 male, age (95% CI) = 6.7 ± 2.6, BMI percentile (95% CI) = 81.0 ± 18.9) were identified. Of these patients, 6 had prior AT. All 9 patients had failed CPAP titration prior to AVAPS titration: 3 failed due to inability to control the apnea-hypopnea index (AHI, events/hour), 2 due to persistent hypercapnia, 2 due to treatment-emergent central sleep apneas, and 2 due to pressure intolerance. All 9 patients showed improvement in AHI following AVAPS titration (mean change = -17.9, 95% CI = 17.9 ± 9.5) as well as improvement in AHI from initial PSG to AVAPS titration (mean change = -42.5, 95% CI = 42.5 ±24.6). 7 patients had reduction in total sleep time with oximetry recording below 90% (T<90) from CPAP to AVAPS titration (mean change = -4.7 minutes, 95% CI = 4.7 ± 14.7), while 8 patients had reduction in T<90 from initial PSG to AVAPS titration (mean change = -14.0 minutes, 95% CI = 14.0 ±24.5). 7 patients had increase in REM sleep from CPAP to AVAPS titration (mean change = +15.9 minutes, 95% CI = 15.9 ±18.3), while 6 patients had increase in REM sleep from initial PSG to AVAPS titration (mean change = +7.7 minutes, 95% CI = 7.7 ±26.6). Conclusion In this case series of children with OSA and with failed CPAP titration, AVAPS is an effective treatment modality. Support (If Any)

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Peak, Megan. "Titration". Ploughshares 41, n.º 4 (2015): 80. http://dx.doi.org/10.1353/plo.2015.0194.

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Liu, Xing Xin y Artem Melman. "Formation of Ternary Complexes of Iron(III) Cations in Solution and Gas Phase". Australian Journal of Chemistry 66, n.º 7 (2013): 791. http://dx.doi.org/10.1071/ch13179.

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Formation of labile 1 : 1 : 1 ternary mononuclear complexes of iron(iii) cation with η3-terdentate meridional binders was studied using electrospray ionisation mass spectrometry (ESI-MS) titration and UV-Vis titration in solution phase. Low selectivities towards formation of ternary heteroleptic complexes in the solution phase vs. symmetric 2 : 1 complexes were obtained with combinations of dianionic 2,6-bis[hydroxy(methyl)amino]-1,3,5-triazine (BHT) ligands with monoanionic terdentate ligands such as 2-[(2-pyridinylmethylene)amino]phenol. Moderate selectivities were observed in formation of ternary iron(iii) complexes of iron(iii) between BHT ligands and neutral terdentate ligands such as pyridin-2-ylmethylpyridin-2-ylmethyleneamine. Results obtained by MS titrations were in a reasonable agreement with UV titration data indicating that quantitative ESI MS spectrometry can be applied to these labile iron(iii) complexes.

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Golovko, Dmitriy, Virender Sharma, Olga Pavlova, Elena Belyanovskaya, Igor Golovko, Victoria Suprunovich y Radek Zboril. "Determination of submillimolar concentration of ferrate(VI) in alkaline solutions by amperometric titration". Open Chemistry 9, n.º 5 (1 de octubre de 2011): 808–12. http://dx.doi.org/10.2478/s11532-011-0069-8.

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AbstractA new amperometric titration method was developed for quantitative determination of ferrate(VI) (FeVIO42−) in the 7.06×10−5−5.73×10−3 M concentration range. Chromium(III) hydroxide solution was used as the titrant. The diffusion current (Id) had a linear relationship with the concentration of ferrate(VI) and slopes were dependent on the concentration of NaOH. The amperometric titration could detect a lower concentration of ferrate(VI) than could potentiometric and colorimetric titrations. The method was applied successfully to determine concentrations of ferrate(VI), generated electrochemically, in strong alkaline solutions.

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Tian, Suming, Minjun Liu, Shina Qiao y Yue Wu. "Rapid titration of opiate doses via patient-controlled intravenous analgesia for patients with severe cancer pain". European Journal of Inflammation 16 (1 de enero de 2018): 205873921877420. http://dx.doi.org/10.1177/2058739218774204.

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This study was to investigate the feasibility and safety of patient-controlled intravenous analgesia for opiate titration in patients with severe cancer. Eligible patients with cancer pain were randomly divided into two groups, which were titrated with a subcutaneous injection of morphine and patient-controlled intravenous analgesia, respectively. The time required for patients to begin titration to reach visual analog scale score ⩽ 3, the adverse reactions during titration, the time spent by nurses in titrating each patient, and the time to complete the titration with a delayed-release dosage form analgesic effect and adverse reaction. The mean titration time of patient-controlled intravenous analgesia group (1.09 ± 0.82 vs 2.97 ± 1.98) and morphine dosage (18.78 ± 12.32 vs 13.23 ± 8.07) were significantly lower than those in the subcutaneous group ( P < 0.05). The incidences of nausea, vomiting, pruritus, urinary retention, and sedation in the subcutaneous injection group were significantly lower than those in the subcutaneous injection group ( P < 0.05). The assessment times of the two groups (10.19 ± 3.72 vs 10.25 ± 4.88) were similar ( P > 0.05). However, the time required for subcutaneous injection in patients under patient-controlled intravenous analgesia was significantly lower than that in the subcutaneous injection group (36.36 ± 12.15 vs 132.36 ± 32.79), which was statistically significant ( P < 0.05). After the titration, the controlled release opioid was used to treat cancer pain. The visual analog scale score of the patient-controlled intravenous analgesia group was significantly lower than that of the subcutaneous group (2.44 ± 1.37 vs 2.73 ± 0.91) at 7 days after treatment in the subcutaneous group (1.05 ± 0.30 vs 2.45 ± 1.29; P < 0.05). Patient-controlled intravenous analgesia technique can effectively and quickly complete the titration of cancer pain treatment with less occupational care resources and is better than the subcutaneous injection titration.

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Davidson, Judy E., Neal Doran, Amber Petty, Daniel L. Arellano, Elizabeth A. Henneman, Sandra K. Hanneman, Hildy Schell-Chaple et al. "Survey of Nurses’ Experiences Applying The Joint Commission’s Medication Management Titration Standards". American Journal of Critical Care 30, n.º 5 (1 de septiembre de 2021): 365–74. http://dx.doi.org/10.4037/ajcc2021716.

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Background Critical care nurses titrate continuous infusions of medications to achieve clinical end points. In 2017, The Joint Commission (TJC) placed restrictions on titration practice, decreasing nurses’ autonomous decision-making. Objectives To describe the practice and perceptions of nurses regarding the 2017 TJC accreditation/regulatory standards for titration of continuous medication infusions. Methods A survey of nurses’ experiences titrating continuous medication infusions was developed, validated, and distributed electronically to members of the American Association of Critical-Care Nurses. Results The content validity index for the survey was 1.0 for relevance and 0.95 for clarity. A total of 781 nurses completed the survey; 625 (80%) perceived titration standards to cause delays in patient care, and 726 (93%) experienced moral distress (mean [SD], 4.97 [2.67]; scale, 0-10). Among respondents, 33% could not comply with titration orders, 68% reported suboptimal care resulting from pressure to comply with orders, 70% deviated from orders to meet patient needs, and 84% requested revised orders to ensure compliance. Suboptimal care and delays in care significantly and strongly (regression coefficients ≥0.69) predicted moral distress. Conclusions Critical care nurses perceive TJC medication titration standards to adversely impact patient care and contribute to moral distress. The improved 2020 updates to the standards do not address delays and inability to comply with orders, leading to moral distress. Advocacy is indicated in order to mitigate unintended consequences of TJC medication management titration standards.

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Duyar, Sezgi Şahin, Deniz Çelik y Selma Fırat. "The Evaluation of APAP Titration Results: Good Titration Versus TECSA and Unacceptable Titration". Turkish Thoracic Journal 22, n.º 6 (19 de noviembre de 2021): 450–58. http://dx.doi.org/10.5152/turkthoracj.2021.21058.

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Sawant, Omkar, Devendra Jagtap, Shah Roshan y Prof Nitin Satao. "Flower Extract of Ixora Coccinea as A Natural Indicator in Acid Base Titration". International Journal for Research in Applied Science and Engineering Technology 10, n.º 4 (30 de abril de 2022): 1547–49. http://dx.doi.org/10.22214/ijraset.2022.41499.

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Abstract: Ixora coccinea Linn may be a species of the genus Ixora, that belongs to the Rubiaceae. The present study indicates the utilization of Ixora coccinea flower extract as an acid base indicator in several sorts of acid base titrations. The equivalence point that was obtained by the flower extract was found to be coincident with the equivalence point obtained by standard indicators. The results obtained by the flower extract matched with the result obtained by standard indicator just in case of weak acid and weak base titration. This natural indicator was found to be a really useful, economical, simple and accurate for the said titration.

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Cassedanne, Jeanníne Odette y Hamílcar Freire de Carvalho. "Dosagem de chumbo em pequenas quantidades nos minerais". Anuário do Instituto de Geociências 14 (1 de diciembre de 1991): 41–43. http://dx.doi.org/10.11137/1991_0_41-43.

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This study describes a lead volumetric titration in minerals. Complexometric accumulation titrations are used and a previous lead separation as chloride is necessary. In the range of 10 to 50 mg of metal, a precision of 0,5 to 0,04% is reached, with a good reproductibility.

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Papanastasiou, Georgios y Georgios Kokkinidis. "Development of Iterative Methods for the Exact Determination of Acid Dissociation Constants and Specific Reaction Rates in Various Ionic or Electrochemical Systems. A Review". Collection of Czechoslovak Chemical Communications 68, n.º 8 (2003): 1345–78. http://dx.doi.org/10.1135/cccc20031345.

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Theory and iterative methods for analysis of potentiometric titration data are presented in this paper. The methods concern titrations of (i) weak monoprotic acids, (ii) mixtures of weak acids with their conjugate bases (buffer solutions), (iii) mixtures of two monoprotic acids, (iv) solutions of polyprotic (di- and triprotic) acids with overlapping ionisation steps, and (v) mixtures of two diprotic acids. Using equations derived without approximations and data exclusively resulting from the buffer region of a titration curve, it is possible to extract the accurate values of the concentration(s) and thermodynamic dissociation constant(s) of the titrated acid(s), even when the titration is stopped well before the end-point of the titration. The main principles of the iterative methods can also be applied to the evaluation of chronoamperometric curves for various electrochemical mechanisms (ECECE, ECE, irreversible, quasi-reversible, and CE). Thus, it is possible to extract the kinetic parameters k1 and k2 of an ECECE mechanism using exclusively chronoamperometric data. The analysis of the chronoamperometric curves for the other mechanisms (ECE, irreversible, quasi-reversible, and CE) permits the extraction of the corresponding kinetic parameters even when the values of the diffusion coefficient D and the effective area A of the electrode are not known. A review with 52 references.

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Prasad, S., V. D. Leite, R. A. C. Santana y E. A. Medeiros. "Electrometric studies on formation of cerium vanadates as a function of pH". Eclética Química 31, n.º 2 (2006): 31–38. http://dx.doi.org/10.1590/s0100-46702006000200005.

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The precise nature of the reaction between nitric acid and sodium ortho-vanadate solutions has been studied by means of electrometric techniques involving potentiometric and conductometric titrations. The well defined inflections and breaks in the titration curves confirm the existence of the anions, pyro-V2O7(4-), meta-VO3- and poly-H2V10O28(4-) corresponding to the ratios of VO4(3-):H+ as 1:1, 1:2 and 1:2.6 in the neighborhood of pH 10.5, 7.4 and 3.6, respectively. The interaction of cerium(III) nitrate with sodium vanadate solutions, at specific pH levels 12.4, 10.5, 7.4 and 3.6 was also studied by potentiometric and conductometric titrations between the reactants. The end-points obtained from the sharp inflections in the titration curves provide definite evidence for the formation and precipitation of cerium ortho-Ce2O3.V2O5, pyro-2Ce2O3.3V2O5 and meta-Ce2O3.3V2O5 vanadates in the neighborhood of pH 7.4, 6.2 and 4.8, respectively. Analytical investigations on the precipitates formed confirm the results of the electrometric study.

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Watanabe, N., J. Levri, V. Peng, S. M. Scharf y M. Diaz. "0634 Volume-Assured Pressure Support is Effective Treatment for Obstructive Sleep Apnea Patients Who Failed CPAP Titration". Sleep 43, Supplement_1 (abril de 2020): A242. http://dx.doi.org/10.1093/sleep/zsaa056.630.

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Abstract Introduction Obstructive sleep apnea (OSA) is a common disease, often treated using continuous positive airway pressure (CPAP). In many cases, patients fail an attended CPAP titration study, often due to inadequate control of AHI, and treatment-emergent central apneas as CPAP is increased. Here, we report our experience using volume-assured pressure support (VAPS) for these patients. Methods We retrospectively reviewed records of 45 adults who had OSA diagnosed on polysomnography (PSG) in whom CPAP titration had failed. In these patients, VAPS-AE (adjustable expiratory pressure) titrations were performed. Patients with central sleep apnea on baseline PSG were excluded. Results Reasons for CPAP titration failure included: treatment emergent central apneas (25), failure of maximum CPAP pressure to treat OSA (18), and persistent hypoxia (2). Average age was 57.9±13.1, BMI was 40.2±8.7, 26 males, Epworth sleepiness score was 10.7±7.9. The following significant changes from baseline PSG to VAPS titration were observed: AHI: 65.3±29.3 to 22.3 ±16.1 (p<.001) events/hour. Time < 88% saturation: 63.7 (median) to 6.9 (median) min (p<.001). The number of patients with AHI<15 was 0 on PSG and 16 (36%) on VAPS-AE, while the number of patients with AHI<30 was 7 (16%) on PSG and 32 (71%) on VAPS-AE. Improvement in AHI was not related to gender, age, or narcotic use, but was correlated with BMI: ΔAHI = 12.2 - (1.4 * BMI); p=.05. VAPS resulted in improved sleep architecture: slow wave sleep increased (medians: 1.4% to 19.6% total sleep time (TST)) (p<.001), REM sleep increased (medians 6.4% to 13.6% TST) (p<.01). Conclusion For OSA patients for whom CPAP titration failed, titration with VAPS-AE was an effective treatment for many patients. Support N/A

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Jacobsen, Jerrold J., Kelly Houston Jetzer, Néha Patani, Gerald Zweerink y John Zimmerman. "Titration Techniques". Journal of Chemical Education 72, n.º 7 (julio de 1995): 612. http://dx.doi.org/10.1021/ed072p612.

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Wood, John T. y Roberta M. Eddy. "Olfactory Titration". Journal of Chemical Education 73, n.º 3 (marzo de 1996): 257. http://dx.doi.org/10.1021/ed073p257.

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Blandamer, Michael J., Paul M. Cullis y Jan B. F. N. Engberts. "Titration microcalorimetry". Journal of the Chemical Society, Faraday Transactions 94, n.º 16 (1998): 2261–67. http://dx.doi.org/10.1039/a802370k.

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Vambhurkar, G., A. Jagtap, A. Gavade, M. Kengar, M. Bhutkar, D. Randive y S. Bhinge. "ETHANOLIC EXTRACT OF ARISTOLOCHIA BRACTEOLATA FLOWER AS A NATURAL INDICATOR FOR ACID-BASE TITRATION". INDIAN DRUGS 56, n.º 03 (28 de marzo de 2019): 77–79. http://dx.doi.org/10.53879/id.56.03.11502.

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In acid-base titration or acid-base neutralization reaction the change in color due to change pH of the solution is caused due to a third substance which is termed as acid-base indicator or pH indicator. Every indicator shows different range of colors at different pH ranges. Synthetic indicators have been widely employed as indicators in acid-base titrations; however, due to environmental pollution, availability and cost, natural compounds are best alternates. Natural pigments in plants are highly colored substances and may show sharp color changes with variation in pH. In the present study an attempt has been made to extract natural indicator from flower of Aristolochia bracteolate. The equivalence points of the titrations namely strong acid-strong base, strong acid-weak base, weak acid-strong base and weak acid weak base titrations, using flower extract of A. bracteolate were coincident with the equivalence points obtained by the synthetic indicator phenolpthalein. From the results of the study, it may be concluded that ethanolic extract of A. bracteolate flower as an indicator for acid-base titration could be effectively employed as a substitute to the synthetic acid-base indicators.

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Ridder, Carsten. "Substitution titration: a new approach to automatic titration". Analytica Chimica Acta 217 (1989): 303–19. http://dx.doi.org/10.1016/s0003-2670(00)80412-2.

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HE, Qing-Yu, Anne B. MASON y Robert C. WOODWORTH. "Spectrophotometric titration with cobalt(III) for the determination of accurate absorption coefficients of transferrins". Biochemical Journal 318, n.º 1 (15 de agosto de 1996): 145–48. http://dx.doi.org/10.1042/bj3180145.

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A rapid and sensitive technique, involving difference spectral titration with cobalt(III), to measure the ϵ values of chicken ovotransferrin, human serum transferrin, the N-lobe of human transferrin and several single point mutants is reported. The resulting ϵ values were compared with the values calculated from the equation proposed by Pace, Vajdos, Fee, Grimsley and Gray [(1995) Protein Sci. 4, 2411–2423]. The titrations with cobalt feature sharp break-points and do not destroy the protein samples. The choice of buffer was found to be important, depending on the metal-binding avidity of the proteins. Cobalt titration should prove useful for studying the comparative metal-binding properties of transferrin and mutants of transferrin being generated by recombinant technology.

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36

Leba, Maria Aloisia Uron, Aloisius Masan Kopon, Yustina Dwisofiani Lawung, Anjelina Derci Jenimat, Faderina Komisia, Maria Benedikta Tukan, Erly Grizca Boelan y Anselmus Boy Baunsele. "Aplication of Turmeric Rhizome Pigmen as Acid-Base Titration Indicator". JURNAL SAINS NATURAL 12, n.º 4 (31 de octubre de 2022): 143. http://dx.doi.org/10.31938/jsn.v12i4.431.

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Turmeric rhizome is a source of natural yellow pigment which can be applied as a pH indicator. This pigment was extracted from turmeric rhizomes using ethanol as a solvent. The purpose of this study was to examine the application of turmeric rhizome pigment extract (TRPE) as an indicator to determine the concentration of H+, the precision and accuracy of the use of TRPE as an indicator of acid base titration. As a comparison, in this study used also a standard indicator, such as phenolphthalein (PP) and methyl red (MR). Titration was carried out on samples without spike and spike samples. The result showed that the rendement of TRPE was 35.72%. The concentration of H+ on the sample without spikes in the titration of strong acid-strong base (SASB) and strong acid-weak base (SAWB) using TRPE, PP and MR indicators gave the same result, namely 0.041 M. The concentration of H+ on spike samples in SASB and SAWB titrations using TRPE, PP and MM indicators gave the same result, namely 0.165 M. The use of TRPE in the titration of SASB, SAWB, weak acid-strong base (WASB) and weak acid-weak base (WAWB) provided good precision with the coefficient of variation (CV) obtained in the titration of samples without spikes and titrations of spike samples, respectively are 1.2% and 0.35%, but only give good accuracy in SASB and SAWB titration with the recovery in the range of 102.3%-102.7%.Keywords: accuracy; acid base; precision; titration; turmeric ABSTRAKAplikasi Pigmen Rimpang Kunyit Sebagai Indikator Titrasi Asam-BasaRimpang kunyit merupakan salah satu sumber pigmen kuning alami yang dapat diaplikasikan sebagai indikator pH. Pigmen ini diperoleh dengan cara mengekstraksinya dari rimpang kunyit menggunakan pelarut etanol. Penelitian ini bertujuan untuk mengkaji aplikasi ekstrak pigmen rimpang kunyit (EPRK) sebagai indikator untuk menentukan konsentrasi H+ dalam sampel, presisi dan akurasi dari penggunaan EPRK sebagai indikator titrasi asam basa. Sebagai pembanding maka dalam penelitian ini digunakan pula indikator standar yakni fenolftalin (PP) dan metil merah (MM). Titrasi dilakukan terhadap sampel tanpa spike dan sampel spike. Berdasarkan hasil penelitian diperoleh rendemen EPRK sebanyak 35,72%. Konsentrasi H+ dalam sampel tanpa spike pada titrasi asam kuat-basa kuat (AKBK) dan asam kuat-basa lemah (AKBL) menggunakan indikator EPRK, PP dan MM memberikan hasil yang sama yaitu 0,041 M. Konsentrasi H+ dalam sampel spike pada titrasi AKBK dan AKBL menggunakan indikator EPRK, PP dan MM memberikan hasil yang sama yaitu 0,165 M. Penggunaan EPRK dalam titrasi AKBK, AKBL, asam lemah-basa kuat (ALBK) dan asam lemah-basa lemah (ALBL) memberikan presisi yang baik dengan coefficient of variation (CV) yang diperoleh pada titrasi sampel tanpa spike dan titrasi sampel spike berturut-turut adalah ˂ 1,2% dan ˂ 0,35%, tetapi hanya memberikan akurasi yang baik pada titrasi AKBK dan AKBL dengan recovery yang diperoleh adalah pada kisaran 102,3%-102,7%.Kata Kunci: akurasi; asam basa; presisi; titrasi; kunyit

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Rodríguez-Laguna, Norma, Alberto Rojas-Hernández, María Teresa Ramírez-Silva, Lucero Hernández-García y Mario Romero-Romo. "An Exact Method to Determine the Conductivity of Aqueous Solutions in Acid-Base Titrations". Journal of Chemistry 2015 (2015): 1–13. http://dx.doi.org/10.1155/2015/540368.

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Several works in the literature show that it is possible to establish the analytic equations to estimate the volumeVof a strong base or a strong acid (VbandVa, resp.) being added to a solution of a substance or a mix of substances during an acid-base titration, as well as the equations to estimate the first derivative of the titration plotdpH/dV, and algebraic expressions to determine the bufferβcapacity with dilutionβdil. This treatment allows establishing the conditions of thermodynamic equilibria for all species within a system containing a mix of species from one or from various polyacid systems. The present work shows that it is possible to determine exactly the electric conductivity of aqueous solutions for these Brønsted acid-base titrations, because the functional relation between this property and the composition of the system in equilibrium is well known; this is achieved using the equivalent conductivityλivalues of each of the ions present in a given system. The model employed for the present work confirms the experimental outcomes with the H2SO4, B(OH)3, CH3COOH, and H3PO4aqueous solutions’ titration.

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Offer, N. W., J. A. Rooke, R. J. Dewhurst y C. Thomas. "Rapid Assessment of Silage Fermentation Characteristics by Electrometric Titration". Proceedings of the British Society of Animal Production (1972) 1993 (marzo de 1993): 19. http://dx.doi.org/10.1017/s0308229600023485.

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Inaccurate prediction of silage intake is often the greatest source of error in ration formulation but improvements have been hindered by an inadequate description of the silage fermentation in advisory practice. Until recently, only pH and ammonia N have been routinely measured as indicators of silage fermentation characteristics. A new method, based on research in Finland (Moisio and Heikonen, 1989) has been developed and is now in use by SAC. This involves automated titration of juice squeezed from the silage to pH 2 (with HC1) followed by stepwise titration (with NaOH) to pH 12. Concentrations of juice constituents are predicted from the buffering capacities measured over segments of the titration curve (pH 2 to pH 12). Calibrations have been obtained empirically by the addition of known increments of standards to a range of silage juices. Proportions of variance (R2) of measurements made by reference methods accounted for by predictions from titrations for a validation set of 93 silages were 0.90, 0.78, 0.92, 0.82 and 0.82 for lactic acid, acetic+butyric acids (VFA), soluble N, sugar and ammonia N respectively.

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Chen, Po-chia, Pawel Masiewicz, Kathryn Perez y Janosch Hennig. "Structure-based screening of binding affinities via small-angle X-ray scattering". IUCrJ 7, n.º 4 (6 de mayo de 2020): 644–55. http://dx.doi.org/10.1107/s2052252520004169.

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Protein–protein and protein–ligand interactions often involve conformational changes or structural rearrangements that can be quantified by solution small-angle X-ray scattering (SAXS). These scattering intensity measurements reveal structural details of the bound complex, the number of species involved and, additionally, the strength of interactions if carried out as a titration. Although a core part of structural biology workflows, SAXS-based titrations are not commonly used in drug discovery contexts. This is because prior knowledge of expected sample requirements, throughput and prediction accuracy is needed to develop reliable ligand screens. This study presents the use of the histidine-binding protein (26 kDa) and other periplasmic binding proteins to benchmark ligand screen performance. Sample concentrations and exposure times were varied across multiple screening trials at four beamlines to investigate the accuracy and precision of affinity prediction. The volatility ratio between titrated scattering curves and a common apo reference is found to most reliably capture the extent of structural and population changes. This obviates the need to explicitly model scattering intensities of bound complexes, which can be strongly ligand-dependent. Where the dissociation constant is within 102 of the protein concentration and the total exposure times exceed 20 s, the titration protocol presented at 0.5 mg ml−1 yields affinities comparable to isothermal titration calorimetry measurements. Estimated throughput ranges between 20 and 100 ligand titrations per day at current synchrotron beamlines, with the limiting step imposed by sample handling and cleaning procedures.

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Bond, T. Christopher, Jaime Rubin, Steven X. Wang y Alex Yang. "More Frequent Hemoglobin Measurements and More Frequent Epoetin Alfa Titrations Are Both Associated with Increased Epoetin Alfa Dose but Not More Time in Target Hemoglobin Range",. Blood 118, n.º 21 (18 de noviembre de 2011): 4194. http://dx.doi.org/10.1182/blood.v118.21.4194.4194.

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Abstract Abstract 4194 For the past 20 years, management of hemoglobin (Hb) level via erythropoiesis-stimulating agents (ESAs), such as epoetin alfa (EPO) has been the norm in the care of end-stage renal disease (ESRD) patients. Recently, questions about patient safety and new economic bundling rules have brought renewed focus on appropriate Hb targets and how they relate to the use of EPO. Important issues related to Hb control are the frequency of Hb measurements, Hb value, the frequency of changes in EPO dose (titrations), and total EPO dose. Current practice aims to achieve greater control of Hb by more frequent measurement and finer EPO dose titrations. No studies have definitively shown that levels of titration and measurement frequency lead to better clinical outcomes or more efficient use of EPO. One large retrospective analysis found increasing Hb measurements and EPO dose titration frequency decreased patient variability around the facility-level Hb mean (Khan et al, 2011). However, a second study found that frequent titrations have been shown to be the most important driver of Hb cycling—potentially dangerous large fluctuations in Hb levels (Fishbane and Berns, 2005). The issue remains controversial. We conducted a retrospective database analysis in order to quantify the frequency of Hb dose titrations and measurements, and to evaluate their relationship to ESA dose and the ability to keep patients within a Hb range of 10–12 g/dL. Data from prevalent (≥ 120 days), adult (>18 years old) hemodialysis patients dialyzing at DaVita dialysis clinics ≥ 3 times per week between January 1, 2009 and December 31, 2010 were included. For every session, patients' stable dosing periods were defined as any series of at least 3 doses during which the dose did not change more than 10% from first dose in the series. Dose holds were defined as ≥ 3 consecutive sessions with 0 EPO dose. An EPO dose of 0 lasting <3 consecutive sessions was ignored when identifying stable periods and holds. Doses not categorized as part of a stable period or a dose hold were considered transition periods. A dose titration was defined as a difference of > 10% between any of the following: the mean dose of 2 consecutive stable periods; the mean dose of stable period and next/previous dose in transition period; and 2 consecutive doses within a transition period. Transitions involving a dose hold were counted as 1 titration if the patient then returned to a dose within 10% of the mean of the prior period; or 2 titrations otherwise. Similar rules were developed for the minority of patients who received EPO once or twice per week. Correlations among measures (titrations/patient-month and Hb measurements/patient-month with mean monthly EPO dose and time with Hb in range) were assessed using Pearson product-moment correlation and linear regression (adjusted for racial composition, percentage of dialysis vascular access types, percentage with comorbidities, and mean age, vintage, and BMI) at the physician and the facility levels. Time in range was defined as total patient time in range/total patient-time. Facility level analyses were weighted by facility load (minimum of 300 patient-months) and are reported here. Information from 81,464 patients at 1,336 facilities was assessed. The mean number of titrations was 13.6 ± 2.83 (mean ± SD) per patient per year and the mean number of Hb measurements was 36.3 ± 8.24 per patient per year. The mean percent of patient-time in range among these facilities was 57.1% ± 5.8%. At the facility level, after adjustment for case mix factors (mean age, vintage, and BMI at facility, access types, and racial composition) the annual number of dose titrations per patient and Hb measurements per patient were not associated with the percent of patient-months within a 10–12 g/dL Hb range (p=0.12 and p=0.47; respectively). An analysis of ESA utilization showed that an increase of 1 titration per patient at the facility level was associated with an extra 18,000 U (p<0.001) per patient. In this retrospective study of >80,000 US dialysis patients over 2 years, neither increased Hb measurements nor increased EPO titrations were associated with improving patient-time in Hb range. However, increased EPO titrations were associated with significantly increased EPO utilization. Although these associations do not demonstrate causality (or the direction of potential causality), they do underscore the need to assess titration practices. Disclosures: Bond: DaVita Clinical Research: Employment; Affymax Inc: Research presented in this study was paid for by Affymax. Rubin:DaVita Clinical Research: Employment; Affymax: The research presented in this abstract was paid for by Affymax. Wang:DaVita Clinical Research: Employment; Affymax: The research presented in this abstract was paid for by Affymax. Yang:Affymax: Employment.

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SUN, Xiao-Bo, Lin LI, Xiu-Xia WANG y Jin-Pi WANG. "A Universal Model for Titrations and Titration Curves Constructed Using MATLAB". University Chemistry 31, n.º 5 (2016): 78–84. http://dx.doi.org/10.3866/pku.dxhx201505015.

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Nalamachu, MD, Srinivas R., Neha Parikh, Larry Dillaha, MD y Richard Rauck, MD. "Lack of correlation between the effective dose of fentanyl sublingual spray for breakthrough cancer pain and the around-the-clock opioid dose". Journal of Opioid Management 10, n.º 4 (1 de julio de 2014): 247. http://dx.doi.org/10.5055/jom.2014.0212.

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Objective: To examine the relationship between the dose of fentanyl sublingual spray needed to control breakthrough cancer pain (BTCP) and the dose of around-the-clock (ATC) opioid used to control background pain.Design: Analysis was based on the open-label, dose-titration phase (up to 26 days) of a randomized, double-blind, placebo-controlled trial.Patients: Opioid-tolerant cancer patients (aged ≥18 years) with chronic pain of ≤moderate severity in the 24 hours before screening while receiving stable doses of scheduled ATC opioid therapy for ≥1 week and 1 to 4 episodes of BTCP per day.Interventions: Fentanyl sublingual spray was initiated at 100 μg. Dose titration proceeded until a dose was reached that provided adequate pain relief for two consecutive BTCP episodes without intolerable adverse effects (AEs).Results: Overall, 98/130 (75.4 percent) patients completed the dose-titration phase and achieved pain relief, and 73.5 percent of those who completed the titration period attained an effective dose of ≥600 μg (median effective dose, 800 μg). No clinically relevant correlation was found between effective doses of fentanyl sublingual spray for the treatment of BTCP and the ATC opioid doses used to control persistent pain (Spearman rank correlation [rs ] = 0.351, n = 98). Sixty percent of patients reported ≥1 AE during the dose-titration phase. The most common AEs considered related to study treatment were nausea (6.2 percent), somnolence (4.6 percent), dizziness (3.8 percent), and vomiting (3.8 percent).Conclusions: These findings highlight the importance of titrating the dose of fentanyl sublingual spray to optimize dosing for individual patients.

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Poon, Gregory M. K. "Explicit formulation of titration models for isothermal titration calorimetry". Analytical Biochemistry 400, n.º 2 (mayo de 2010): 229–36. http://dx.doi.org/10.1016/j.ab.2010.01.025.

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González-Arjona, Domingo, Emilio Roldán González, Germán López-Pérez, Manuel María Domínguez Pérez y Marina Calero-Castillo. "Coulometer from a Digitally Controlled Galvanostat with Photometric Endpoint Detection". Sensors 22, n.º 19 (5 de octubre de 2022): 7541. http://dx.doi.org/10.3390/s22197541.

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In this work, a coulometer was developed from a digitally controlled galvanostat. A simple colorimeter based on a RGB LED was used as a light emitter coupled to light detectors, while light dependent resistance (LDR) and photodiodes have been developed as endpoint detectors. Both hardware and software have been adapted from the original galvanostat design. Regarding the hardware, new electrical signal conditioners (filters and voltage dividers) were included to optimize the working system. The software was developed based on an open source Arduino UNO microcontroller. The different variables that control the titration process are managed by an add-in module for Excel data acquisition software that is freely available. A study of the possible variables that influence the titration process has been carried out. The system was tested with two classical coulometric titrations such as iodometry (thiosulfate, ascorbic acid) and acid/base (potassium acid phthalate as standard). The developed system is versatile as different endpoint color indicators can be employed (starch and phenolphthalein for the investigated reactions). Different experimental arrangements have been studied: the nature of the electrodes (Pt, Ag), type of cells (two separate compartments or a single compartment), and light detectors (LDR, photodiode). The influence of several experimental parameters (both electrical, light, and integration time) was studied and chosen to obtain the best performance of the complete system. Reproducibility results below 1% can be obtained under controlled conditions. In the case of acid/base titrations, the presence of atmospheric carbon dioxide was detected, whose interference was mainly affected by the stirring rate and the titration time.

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Wells, DNSc, RN, Nancy, Barbara Murphy, MD, Stacey Douglas, MSN, RN y Nancy Yelton, MSN, RN. "Establishing the safety and efficacy of an opioid titration protocol". Journal of Opioid Management 1, n.º 1 (1 de marzo de 2005): 41. http://dx.doi.org/10.5055/jom.2005.0011.

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The primary goal of this single-group study was to determine the safety of a standard opioid titration order sheet to manage pain in ambulatory cancer patients. Secondary goals were to examine opioid toxicity and efficacy of this pain protocol.Twenty-seven patients who required fixed-dose opioids and who had uncontrolled pain were enrolled. All patients had their initial opioid dose titrated by the study physician using the opioid titration order sheet. Data were obtained by the study nurse during a weekly telephone interview and used to determine if pain was controlled. After initial titration, a trained study nurse titrated opioid doses based upon the standing order sheet. At each contact, patients were assessed for adverse effects, pain intensity, and analgesics used.Patients who completed the four-week trial (n = 17) did not differ from patients who did not complete the trial. No adverse effects were observed in 39 opioid titrations com-pleted by the study nurse. Opioid toxicities, worst pain, usual pain, and pain-related distress declined from baseline to week four. Patients who were adherent to their prescribed medications reported significantly lower pain intensity and distress (ps < 0.06).The opioid titration order sheet, used by a trained nurse, is safe to use in ambulatory cancer patients who have moderate to severe pain. Common opioid toxicities were reduced. The protocol also demonstrated initial efficacy in improving worst and usual pain and pain-related distress. Further research to establish efficacy of theprotocol is recommended.

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Bindewald, Eduardo Henrique, João Carlos Rosa-Sobrinho, Márcio Fernando Bergamini y Luiz Humberto Marcolino-Júnior. "Simple, fast and inexpensive method for determination of ranitidine hydrochloride based on conductometric measurements". Eclética Química Journal 43, n.º 4 (5 de diciembre de 2018): 37. http://dx.doi.org/10.26850/1678-4618eqj.v43.4.2018.p36-42.

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This work aims the development and optimization of an alternative method for ranitidine hydrochloride (RAN-HCl) determination. The proposed method was based on conductometric titration of RAN by precipitation of AgCl solid using a solution of AgNO3 as titrant. It was investigated the possibility of performing the titrations on hydroalcoholic and deionized water medium. A limit of detection of 1.0 mmol L-1 and 0.5 mmol L-1 were achieved for RAN titration in deionized water and in a 75:25 hydroalcoholic mixture, respectively. Such behavior is attributed to the dielectric constant of hydroalcoholic medium, which is lower than aqueous solution, making AgCl more insoluble and improving the resolution of the conductivity curve around the end point. Therefore, it is concluded that the conductometric titration method to determine RAN using AgNO3 as titrant proved to be feasible at low drug concentrations. The statistical calculations for obtained results suggested good precision for the conductometric method. According to t-test, there were no significant differences between found values at a 95% confidence level. Moreover, obtained results showed an excellent performance of the proposed method on quality control of RAN-HCl in generic formulations without any sample pretreatment.

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Bindewald, Eduardo Henrique, João Carlos Rosa-Sobrinho, Márcio Fernando Bergamini y Luiz Humberto Marcolino-Júnior. "Simple, fast and inexpensive method for determination of ranitidine hydrochloride based on conductometric measurements". Eclética Química Journal 43, n.º 4 (7 de enero de 2019): 37. http://dx.doi.org/10.26850/1678-4618eqj.v43.4.2018.p37-43.

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This work aims the development and optimization of an alternative method for ranitidine hydrochloride (RAN-HCl) determination. The proposed method was based on conductometric titration of RAN by precipitation of AgCl solid using a solution of AgNO3 as titrant. It was investigated the possibility of performing the titrations on hydroalcoholic and deionized water medium. A limit of detection of 1.0 mmol L-1 and 0.5 mmol L-1 were achieved for RAN titration in deionized water and in a 75:25 hydroalcoholic mixture, respectively. Such behavior is attributed to the dielectric constant of hydroalcoholic medium, which is lower than aqueous solution, making AgCl more insoluble and improving the resolution of the conductivity curve around the end point. Therefore, it is concluded that the conductometric titration method to determine RAN using AgNO3 as titrant proved to be feasible at low drug concentrations. The statistical calculations for obtained results suggested good precision for the conductometric method. According to t-test, there were no significant differences between found values at a 95% confidence level. Moreover, obtained results showed an excellent performance of the proposed method on quality control of RAN-HCl in generic formulations without any sample pretreatment.

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48

Abdulrahman, Sameer y Kanakapura Basavaiah. "Application of ion-association titration for the assay of bupropion hydrochloride in pharmaceuticals". Chemical Industry and Chemical Engineering Quarterly 17, n.º 3 (2011): 299–306. http://dx.doi.org/10.2298/ciceq110210015a.

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Two simple and rapid titrimetric methods are described for the determination of bupropion hydrochloride (BUPH) in pharmaceuticals. The proposed methods are based on the solvent extraction-titration of BUPH with two ion-association reagents, i.e. sodium lauryl sulphate (SLS) and tetraphenylborate (TPB). In method A, SLS was used as titrant and the titration was carried out in the presence of dilute sulphuric acid and chloroform using dimethyl yellow as indicator whereas in method B, the titrant was TPB and the titration was done in borate-phosphate buffer of pH 6.0 and 1,2-dichloroethane with tetrabromophenolphthalein ethyl ester (TBPE) as indicator. In the two-phase titrations, the proposed procedures give sharp end points as the color of the organic phase changes from yellow to pink in method A and from red-violet to yellow in method B. The methods are applicable over the ranges of 1.0-20.0 and 3.0-10.0 mg of BUPH for method A and method B, respectively. The accuracy and precision of the methods are good. The methods were applied successfully to the determination of BUPH in tablets and the results were in agreement with the label claim and those of the comparison method.

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Davidson, Judy E., Laura Chechel, Jose Chavez, Carol Olff y Teresa Rincon. "Thematic Analysis of Nurses’ Experiences With The Joint Commission’s Medication Management Titration Standards". American Journal of Critical Care 30, n.º 5 (1 de septiembre de 2021): 375–84. http://dx.doi.org/10.4037/ajcc2021280.

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Background For decades, medication titration has been within nurses’ scope and practice. In 2017 The Joint Commission (TJC) revised elements for orders for the titration of continuous intravenous medications. Objectives To explore the practice and perceptions of nurses regarding TJC standards for titration of continuous intravenous medications. Methods Nurses with experience titrating medications completed an investigator-designed, validated cross-sectional survey. Inductive thematic analysis was conducted in order to analyze the open-ended comments from that quantitative survey. Results From among 730 completed surveys, 159 comments were received. Analysis of the comments yielded 3 levels of abstraction. Two overarching themes were harm and professionalism. Additional abstraction for the harm theme revealed categories of erosion of workplace wellness, moral dilemma, and patient safety, which were coded as relating to workplace stress, workload, burnout/turnover, physical risk, inefficiency, demeaning/devalued, falsification of records, problematic orders, burden of documentation, suboptimal care, delay in care, individualized care, and provider availability. Within the professionalism theme, categories of autonomy and nurse proficiency were identified, with 7 associated codes: top of scope, critical thinking, overregulation, teamwork, education, registered nurse knowledge, and novice registered nurse guidance. Conclusions The standards from TJC impose harm by eroding workplace wellness and introducing moral dilemmas and patient safety concerns. Professionalism is threatened through limits on scope and autonomy. Further advocacy is necessary in order to resolve unanticipated consequences related to the titration standards.

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Pagariya, R. F. "GREEN CHEMISTRY: ROSELLE’S COROLLA EXTRACT AS A SUBSTITUTE FOR HAZARDOUS INTERNAL INDICATORS IN VOLUMETRIC ANALYSIS". International Journal of Research -GRANTHAALAYAH 7, n.º 9 (30 de septiembre de 2019): 118–22. http://dx.doi.org/10.29121/granthaalayah.v7.i9.2019.567.

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Indicators used in acid-base titration show well marked changes of colour in certain intervals of pH. Most of these indicators are organic dyes and are of synthetic origin. Today synthetic indicators are the choice of neutralization titrations. But due to environmental pollution, availability and cost, the search for natural compounds as an acid-base indicator was started. The present work highlights the use of the ethanolic extract of the corolla of Roselle (Hibiscus sabdariffa) as a pH indicator in strong acid-strong base, strong acid weak base, weak acid strong base and weak acid-weak base titrations. This natural indicator is easy to extract as well as easily available. The results showed that the Roselle’s corolla indicator gave red color in acidic solution, while green in basic solution. The comparison indicators used in this research were phenolphthalein, methyl red and phenol red. Hopeful results were obtained when it was compared against standard synthetic indicators. The equivalence points obtained match with the equivalence points obtained by standard indicators. Therefore this natural indicator is found to be useful, economical, simple, precise and eco-friendly for acid base titration.

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