Home  About us  Contact
 

Index Measurement (index + measurement)

Distribution by Scientific Domains
Polymers and Materials Science30%
Medical Sciences30%
Physics and Astronomy23%

Kinds of Index Measurement

  • refractive index measurement
    		•

    Selected Abstracts

    Body Mass Index Measurement in Schools,

    JOURNAL OF SCHOOL HEALTH, Issue 10 2007
    Allison J. Nihiser MPH
    ABSTRACT Background:, School-based body mass index (BMI) measurement has attracted much attention across the nation from researchers, school officials, legislators, and the media as a potential approach to address obesity among youth. Methods:, An expert panel, convened by the Centers for Disease Control and Prevention (CDC) in 2005, reviewed and provided expertise on an earlier version of this article. The panel comprised experts in public health, education, school counseling, school medical care, and a parent organization. This article describes the purposes of BMI measurement programs, examines current practices, reviews existing research, summarizes the recommendations of experts, identifies concerns, and provides guidance including a list of safeguards and ideas for future research. Results:, The implementation of school-based BMI measurement for surveillance purposes, that is, to identify the percentage of students in a population who are at risk for weight-related problems, is widely accepted; however, considerable controversy exists over BMI measurement for screening purposes, that is, to assess the weight status of individual students and provide this information to parents with guidance for action. Although some promising results have been reported, more evaluation is needed to determine whether BMI screening programs are a promising practice for addressing obesity. Conclusions:, Based on the available information, BMI screening meets some but not all of the criteria established by the American Academy of Pediatrics for determining whether screening for specific health conditions should be implemented in schools. Schools that initiate BMI measurement programs should evaluate the effects of the program on BMI results and on weight-related knowledge, attitudes, and behaviors of youth and their families; they also should adhere to safeguards to reduce the risk of harming students, have in place a safe and supportive environment for students of all body sizes, and implement science-based strategies to promote physical activity and healthy eating. [source]

    Equivalences between refractive index and equilibrium water content of conventional and silicone hydrogel soft contact lenses from automated and manual refractometry,

    JOURNAL OF BIOMEDICAL MATERIALS RESEARCH, Issue 1 2007
    José M. González-Méijome
    Abstract Purpose The purpose of the present study was to develop mathematical relationships that allow obtaining equilibrium water content and refractive index of conventional and silicone hydrogel soft contact lenses from refractive index measures obtained with automated refractometry or equilibrium water content measures derived from manual refractometry, respectively. Methods Twelve HEMA-based hydrogels of different hydration and four siloxane-based polymers were assayed. A manual refractometer and a digital refractometer were used. Polynomial models obtained from the sucrose curves of equilibrium water content against refractive index and vice-versa were used either considering the whole range of sucrose concentrations (16,100% equilibrium water content) or a range confined to the equilibrium water content of current soft contact lenses (,20,80% equilibrium water content). Results Values of equilibrium water content measured with the Atago N-2E and those derived from the refractive index measurement with CLR 12,70 by the applications of sucrose-based models displayed a strong linear correlation (r2 = 0.978). The same correlations were obtained when the models are applied to obtain refractive index values from the Atago N-2E and compared with those (values) given by the CLR 12,70 (r2 = 0.978). No significantly different results are obtained between models derived from the whole range of the sucrose solution or the model limited to the normal range of soft contact lens hydration. Conclusions Present results will have implications for future experimental and clinical research regarding normal hydration and dehydration experiments with hydrogel polymers, and particularly in the field of contact lenses. © 2006 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2007 [source]

    Li-Deficient, Off-Congruent MgO:LiNbO3 Crystals Prepared by Postgrown Li-Poor Vapor Transport Equilibration for Integrated Optics

    JOURNAL OF THE AMERICAN CERAMIC SOCIETY, Issue 7 2010
    De-Long Zhang
    Li-deficient, off-congruent Z -cut MgO:LiNbO3 (MgO:LN) crystals for integrated optics were prepared by carrying out postgrown Li-poor vapor transport equilibration (VTE) treatments on congruently grown MgO (5 mol% in melt):LiNbO3 plates at 1100°C for durations ranging from 40 to 395 h. Secondary ion mass spectrometry analysis, surface ordinary refractive index measurement, and neutron activation analysis were carried out on the VTE crystals to verify that the Mg and Nb ions did not diffuse out of the crystal during the VTE procedure and their distributions over the whole plate retain its homogeneity. The VTE duration dependence of the Li2O content reduction was determined using gravimetric method, and the crystalline phase was by powder X-ray diffraction. The results show that the Li2O content decreases with a prolonged VTE and the Li2O content reduction in the saturation regime is about 2.9 mol%. All of the VTE crystals still retain the LN phase, and Li-vacancy and NbLi are the major defects in the VTE crystal. OH absorption study reveals that the doped MgO concentration is below the photorefractive threshold for all VTE crystals. The optical absorption edge (OAE) of the VTE-treated MgO:LN was also measured as a function of the VTE duration. On the basis of the known Li2O content and measured OAE, the photon-energy fit reported previously, valid for the evaluation of Li2O content in a pure LN, is corrected for the Li-poor VTE-treated MgO:LNs. Finally, the applicability of the Li-deficient off-congruent MgO:LN crystals prepared by the Li-poor VTE method is demonstrated by characterizing the optical damage and Er diffusion properties of a single-mode Ti:MgO:Er:LiNbO3 strip waveguide fabricated on an Li-poor VTE-prepared MgO:LN crystal. [source]

    Spatial refractive index measurement of porcine artery using differential phase optical coherence microscopy

    LASERS IN SURGERY AND MEDICINE, Issue 10 2006
    Jeehyun Kim PhD
    Abstract Background and Objectives We describe a methodology to record spatial variation of refractive index of porcine renal artery using differential phase optical coherence microscopy (DP-OCM). Study Design/Materials and Methods The DP-OCM provides quantitative measurement of thin specimen phase retardation and refractive index by measuring optical path-length changes on the order of a few nanometers and with a lateral resolution of 3 µm. The DP-OCM instrumentation is an all-fiber, dual-channel Michelson interferometer constructed using a polarization maintaining (PM) fiber. Results Two-dimensional en face dual-channel phase images are taken over a 150,×,200 µm region on a microscopic slide, and the images are reconstructed by plotting a two-dimensional refractive index map as the OCM beam is moved across the sample. Conclusions Because the DP-OCM can record transient changes in the optical path-length, the system may be used to record quantitative optical path-length alterations of tissue in response to various stimuli. A fiber-based DP-OCM may have the potential to substantially improve in vivo imaging of individual cells for a variety of clinical diagnostics, and monitoring applications. Lasers Surg. Med. © 2006 Wiley-Liss, Inc. [source]

    Spoliation of a rigid gas permeable contact lens by sodium chloride: A free volume microprobe study

    PHYSICA STATUS SOLIDI (C) - CURRENT TOPICS IN SOLID STATE PHYSICS, Issue 11 2009
    M. V. Deepa Urs
    Abstract The interaction of one of the major inorganic ions present in tears, viz., sodium chloride (NaCl), with a rigid gas permeable contact lens, poly(Fluorosilicone acrylate) (FP92) has been investigated using Positron Annihilation Lifetime Spectroscopy (PLS) and refrac-tive index measurement. We monitored the changes in its free volume size and number density in the presence of NaCl solute trans-ported through diffusion. Based on PLS results, we propose that the adhesion of sodium chloride salt to the fluorine and methacrylate sites of FP92 results in zones of excess salt concentration. The changes in refractive index of the contact lens material due to the salt adhesion, correlates well with the changes in free volume of the material. Presence of sodium chloride perturbs the free volume of the lens material and hence its polarizability (© 2009 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source]

    Determination of linear birefringence of a multiple-order wave plate using a phase-sensitive ellipsometer

    PHYSICA STATUS SOLIDI (C) - CURRENT TOPICS IN SOLID STATE PHYSICS, Issue 5 2008
    H. C. Wei
    Abstract A phase-sensitive interferometric ellipsometer is setup in order to characterize linearly birefringent parameters (no,ne,m) of a multiple-order wave plate (MWP) precisely where no and ne are refractive indices of ordinary and extraordinary rays respectively while m is the number of the order of interference. In order to avoid multiple reflections in MWP during the phase retardation measurement at oblique incidence, two tilted phase retardations with respect to the oblique incident angle rotated along x-axis and y-axis are measured and then subtracted from each other. In the mean time, the spatial shifting effect of the emerging beams from MWP is reduced too. This results the accuracy of linear birefringence measurement. Finally, a multiple-order quartz wave plate was tested. The experimental results verify that the phase-sensitive interferometric ellipsometer is able to precisely measure linear birefringence and the order number of a MWP. In this measurement, the phase stability of the interferometric ellipsometer was 0.3°/hr. It implies the sensitivity on refractive index measurement at ,n , 10,6 was achieved in the experiment. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source]

    Therapy of peri-implantitis with resective surgery

    CLINICAL ORAL IMPLANTS RESEARCH, Issue 1 2005
    A 3-year clinical trial on rough screw-shaped oral implants.
    Abstract: The purpose of this randomized clinical trial was to compare the clinical outcome of two different surgical approaches for the treatment of peri-implantitis. Seventeen patients with ITI® implants were included consecutively over a period of 5 years. The patients were randomized with a lottery assignment. Ten patients were treated with resective surgery and modification of surface topography (test group). The remaining seven patients were treated with resective surgery only (control group). Clinical parameters (suppuration, modified plaque index , mPI, modified bleeding index , mBI, probing pocket depth , PPD, pseudopocket , DIM, mucosal recession , REC, probing attachment level , PAL) were recorded at baseline, as well as 6, 12, 24 and 36 months after treatment. The cumulative survival rate for the implants of the test group was 100% after 3 years. After 24 months, two hollow-screw implants of control group were removed because of mobility. Consequently, the cumulative survival rate was 87.5%. The recession index in the control group was significantly lower than in the test group at 24 months (Student's t -value of ,2.14). On the contrary, control group showed higher PPD, PAL and mBI indexes than test group (Student's t -values of +5.5, +2.4 and +9.61, respectively). The PPD and mBI indexes for the implants of the control group were significantly higher at baseline than 24 months later (Student's t -values of +3.18 and +3.33, respectively). Recession and PAL indexes resulted in values significantly lower than baseline (Student's t -values of ,4.62 and ,2.77, respectively). For the implants of the test group PPD and mBI indexes were significantly higher at baseline than 36 months after (Student's t -values of +11.63 and +16.02, respectively). Recession index resulted in values significantly lower at baseline (Student's t -value of ,5.05). No statistically significant differences were found between PAL index measurement at baseline and 36 months later (Student's t -value of +0.89). In conclusion, resective therapy associated with implantoplasty seems to influence positively the survival of oral implants affected by inflammatory processes. Résumé Le but de cet essai clinique randomisé a été de comparer la guérison clinique de deux approches chirurgicales différentes pour le traitement de la paroïmplantite. Dix-sept patients avec des implants ITI® ont été inclus dans cette étude durant une période de cinq années. Les patients étaient répartis au hasard. Dix patients étaient traités avec une chirugie de résection et une modification de la topographie de surface (groupe test). Les derniers sept patients ont été traités avec la chirurgie de résection seulement (groupe contrôle). Des paramètres cliniques [suppuration, indice de plaque modifiée (mPI), indice de saignement modifié (mBI), profondeur de poche au sondage (PPD), pseudo poches (DIM), récession de la muqueuse (Rec), niveau d'attache au sondage (PAL)] ont été mesurés lors de l'examen initial et après six, douze, 24 et 36 mois. Le taux cumulatif pour les implants dans le groupe test était de 100% après trois années. Après 24 mois, deux implants vis creux du groupe contrôle ont été enlevés à cause de la mobilité. En conséquence, le taux de survie cumulatif était de 87,5%. L'indice de récession dans le groupe contrôle était significativement inférieur à celui du groupe test à 24 mois (valeur du test T de Student ,2,14). Par contre le groupe contrôle montrait des indices plus importants de PPD, PAL et mBI que le groupe test (valeurs du test T de Student respectivement de+5,50,+2,40,+9,61). Les indices PPD et mBI pour les implants du groupe contrôle étaient significativement plus importants lors de l'examen initial que 24 mois plus tard (valeurs du test T de Student respectivement de+ 3,18 et+3,33). Les indices de récession et de PAL résultaient en indices significativement inférieures que lors de l'examen initial (valeurs du test T de Student respectivement de ,4,62, ,2,77). Pour les implants du groupe test, les indices PPd et mBI étaient significativement plus importants lors de l'examen initial que 36 mois plus tard (valeurs du test T de Student respectivement de+11,63, 16,02). L'indice de récession résultait en indice significativement inférieur lors de l'examen initial (valeurs du test T de Student ,5,05). Aucune différence significative n'a été trouvée pour la mesure de l'indice PAL entre l'examen initial et 36 mois (valeur du test T de Student de+0,89). En conclusion, le traitement de résection associéà une plastieimplantaire semble influencer de manière positive la survie des implants dentaires affectés par les processus infectieux. Zusammenfassung Das Ziel dieser randomisierten klinischen Studie war, die klinischen Resultate von zwei verschiedenen chirurgischen Behandlungsvarianten der Periimplantitis zu vergleichen. Man nahm während einer Zeitdauer von fünf Jahren 17 Patienten mit ITI®-Implantaten fortlaufend in die Studie auf. Mit einem lotterieartigen System teilte man die Patienten zufällig auf. 10 der Patienten erhielten eine resektive Chirurgie und man modifizierte zusätzlich die Implantatoberfläche (Testgruppe). Bei den übrigen 7 wandte man ausschliesslich die resektive Chirurgie an (Kontrollgruppe). Zu Beginn sowie 6, 12, 24 und 36 Monate nach der Behandlung erhob man folgende klinischen Parameter: Eiterung, modifizierter Plaqueindex , mPI, modifizierter Blutungsindex , mBI, Sondierungstiefe , PPD, Pseudotaschen , DIM, Mukosarezession , Rec, sondierbares Attachmentniveau , PAL. Die kumulative Überlebensrate der Implantate in der Testgruppe betrug nach 3 Jahren 100%. Nach 24 Monaten mussten infolge Mobilität 2 Hohlschraubenimplantate der Kontrollgruppe entfernt werden. Daher betrug die kumulative Überlebensrate hier 87.5%. Der Rezessionsindex nach 24 Monaten war in der Kontrollgruppe signifikant tiefer als in der Testgruppe (T-Student Wert ,2.14). Dagegen zeigte die Kontrollgruppe höhere Indices bei der PPD, dem PAL und beim mBI als die Testgruppe (T-Student Werte von +5.5/+2.4 und +9.61). Die PPD und die mBI-Indices der Implantate aus der Kontrollgruppe waren zu Beginn signifikant höher als 24 Monate später (T-Student Werte von +3.18 und +3.33). Die Rezessions- und PAL-Indices waren dagegen signifikant tiefer als zu Beginn (T-Student Werte von ,4.62 und ,2.77). Bei den Implantaten der Testgruppe waren die PPD- und mBI-Indices zu Beginn signifikant höher als nach 36 Monaten (T-Student Werte von +11.63 und +16.02). Der Rezessionsindex war bei Studienbeginn signifikant tiefer (T-Student Wert von ,5.05). Bei den Messungen des PAL-Index konnte man zwischen den Anfangswerten und denjenigen nach 36 Monaten keine statistisch signifikanten Unterschiede erkennen (T-Student Wert von +0.89). Zusammenfassend kann man feststellen, dass eine resektive Therapie verbunden mit einer Oberflächenveränderung, die Überlebensrate der von einem entzündlichen Prozess betroffenen Implantate positiv zu beeinflussen vermag. Resumen El propósito de este estudio clínico aleatorio fue comparar los resultados clínicos de dos enfoques quirúrgicos diferentes para el tratamiento de periimplantitis. Se incluyeron a diecisiete pacientes consecutivos con implantes ITI® durante un periodo de cinco años. Los pacientes se asignaron aleatoriamente por medio de un sistema de lotería. Se trató a diez pacientes con cirugía resectiva y modificación de la topografía de superficie (grupo de prueba). Los siete pacientes restantes se trataron con cirugía resectiva solamente (grupo de control). Se recogieron parámetros clínicos (supuración, índice de placa modificado , mPI, índice de sangrado modificado , mBI, profundidad de sondaje de la bolsa , PPD, pseudobolsa , DIM, recesión mucosa , REC, nivel de inserción al sondaje , PAL) al inicio, al igual que a los 6, 12, 24 y 36 meses tras el tratamiento. El índice acumulativo de éxito del grupo de prueba tras 3 años fue del 100%. A los 24 meses se retiraron dos implantes huecos roscados del grupo de control debido a movilidad. Consecuentemente el índice acumulado de supervivencia fue del 87.5%. El índice de recesión en el grupo de control fue significativamente más bajo que en el grupo de prueba a los 24 meses (valor T-student de ,2.14). Por el contrario, el grupo de control mostró unos índices PPD, PAL y mBI mas altos que en el grupo de prueba (valores de T-student de +5.5 +2.4 y +9.61 respectivamente). Los índices PPD y mBI para los implantes del grupo de control fueron significativamente mas altos al inicio que 24 meses mas tarde (valores de T-student de +3.18 y +3.33 respectivamente). Los índices de recesión y PAL resultaron significativamente mas bajos que al inicio (valores de T-student de ,4.62 y ,2.77 respectivamente). Para los implantes del grupo de prueba los índices PPD y mBI fueron significativamente mas altos al inicio que tras 36 meses (valores de T-student de +11.63 y +16.02 respectivamente). El índice de recesión resultó ser significativamente más bajo al inicio (valores de T-student de ,5.05). No se encontraron diferencias estadísticamente significativas para las mediciones de índice de PAL al inicio y 36 meses mas tarde (valores de T-student de +0.89). En conclusión, la terapia resectiva asociada con implantoplastia parece influir positivamente sobre la supervivencia de los implantes orales afectados por procesos inflamatorios. [source]

    Effect of aging and degeneration on disc volume and shape: A quantitative study in asymptomatic volunteers

    JOURNAL OF ORTHOPAEDIC RESEARCH, Issue 5 2006
    Christian W. A. Pfirrmann
    Abstract Debate continues on the effect of disc degeneration and aging on disc volume and shape. So far, no quantitative in vivo MRI data is available on the factors influencing disc volume and shape. The objective of this MRI study was to quantitatively investigate changes in disc height, volume, and shape as a result of aging and/or degeneration omitting pathologic (i.e., painful) disc alterations. Seventy asymptomatic volunteers (20,78 years) were investigated with sagittal T1- and T2-weighted MR-images encompassing the whole lumbar spine. Disc height was determined by the Dabbs method and the Farfan index. Disc volume was calculated by the Cavalieri method. For the disc shape the "disc convexity index" was calculated by the ratio of central disc height and mean anterior/posterior disc height. Disc height, disc volume, and the disc convexity index measurements were corrected for disc level and the individuals age, weight, height, and sex in a multilevel regression analysis. Multilevel regression analysis showed that disc volume was negatively influenced by disc degeneration (p,<,0.001) and positively correlated with body height (p,<,0.001) and age (p,<,0.01). Mean disc height and the disc convexity index were negatively influenced by disc degeneration but not by gender, weight, and height. Disc height was positively correlated with age (p,<,0.01). From the results of this study, it can be concluded that disc degeneration generally results in a decrease of disc height and volume as well as a less convex disc shape. In the absence of disc degeneration, however, age tends to result in an inverse relationship on disc height, volume, and shape. © 2006 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res [source]

    Color inhibition of phenolic antioxidants in Ziegler-Natta polyethylene.

    JOURNAL OF VINYL & ADDITIVE TECHNOLOGY, Issue 1 2009

    Although the level of transition-metal catalyst residues in polyethylene (PE) has been drastically reduced over the years, they can still give rise to discoloration, particularly when associated with other additives such as antioxidants. This first of this series of papers screens a variety of candidate color suppressants featuring a range of functional groups, including alcohols, amine/sulfur compounds, and acid-containing species. These candidate color suppressants were melt-blended into a Ziegler-Natta linear low-density PE in combination with 2,2,-isobutylidenebis(4,6-dimethylphenol) (a highly discoloring hindered bisphenol antioxidant) and zinc stearate antacid. Yellowness index measurements made after multiple extruder passes indicated that dipentaerythritol (DPE) and triisopropylamine (TIPA) gave good color inhibition and, in some cases, outperformed established phosphites. The DPE and TIPA were found (via melt flow rate measurement) not to affect melt stability, and hydroperoxide determination revealed that DPE had no peroxide decomposition activity. The latter results indicate that the color-suppression mechanism of DPE and TIPA is different from that associated with phosphites. J. VINYL ADDIT. TECHNOL., 2009. © 2009 Society of Plastics Engineers [source]

    Monitoring of blood proteins glycation by refractive index and spectral measurements

    LASER PHYSICS LETTERS, Issue 6 2008
    O.S. Zhernovaya
    Abstract Monitoring of blood glucose and glycated proteins level is an urgent requirement for diabetic patients. The amount of glycated hemoglobin and glycated albumin depends on blood glucose concentration and reflects the mean glycemia. The purpose of this study is to investigate the effect of presence of glucose and glycation of proteins on optical properties of water solutions of hemoglobin and albumin with different glucose concentrations. We present the results of feasibility study of the refractive index measurements for water solutions of hemoglobin and albumin with glucose by Abbe refractometer. In addition, absorbance spectrum of water solutions of hemoglobin and albumin with different glucose concentrations has been studied. The experimental results show that the changes of optical properties caused by glycation of proteins can be observed by refractive index and spectral measurements. The refractive index measurements can be potentially applied for evaluation of glycated hemoglobin and glycated albumin amount in blood. (© 2008 by Astro Ltd., Published exclusively by WILEY-VCH Verlag GmbH & Co. KGaA) [source]

    Commercial devices measuring UV radiation: a good choice for the public?

    PHOTODERMATOLOGY, PHOTOIMMUNOLOGY & PHOTOMEDICINE, Issue 5 2010
    Alberto Pettazzi
    Commercial devices measuring UV radiation are available on the market at affordable prices. This work presents the response of six commercial devices in comparison to UV index measurements and in relation to the guidelines provided by the INTERSUN programme. Taking everything into account, overestimated or non-standard data, and ambiguous or incomplete information was found. Instead of using these gadgets, people should refer to official information and advice provided by health and weather services. [source]

    Determination of molar mass and solution properties of cationic hydroxyethyl cellulose derivatives by multi-angle laser light scattering with simultaneous refractive index detection

    POLYMER INTERNATIONAL, Issue 10 2009
    Wei Gao
    Abstract BACKGROUND: A complete understanding of the molar mass and solution properties of raw materials in bio/pharmaceutical products under bio-application and natural conditions ensures process control, product performance and quality. Biopolymers including polymeric cationic hydroxyethyl cellulose derivatives (e.g. Polyquaterium-10 or Polymer JR) have long been used in health care formulations including shampoos, lotions, eye drops and contact lens multi-purpose solutions. Previously reported molar masses and conformation of Polymer JR were based on size exclusion chromatography-related techniques, which required highly concentrated buffered salt solutions and organic solvent modifiers to prevent undesirable interactions, and did not represent the isotonic conditions in products and applications. RESULTS: This paper describes the characterization of Polymer JR in saline using a new approach that combines micro-batch mode multi-angle laser light scattering with simultaneous refractive index measurements (MB-MALLS-RI). Mass-average molar mass, z -average radius of gyration and second virial coefficient values in phosphate buffer saline (PBS) were obtained and are discussed in detail. CONCLUSION: The molar mass and solution properties of Polymer JR in PBS, with the same pH and ionic strength as most health care solution products, can be characterized using the MB-MALLS-RI technique. The approach is practical and can be widely used for the analysis of other cationic biopolymers. Copyright © 2009 Society of Chemical Industry [source]

    Ultrasound-facilitated electro-oxidation for treating cyan ink effluent

    THE CANADIAN JOURNAL OF CHEMICAL ENGINEERING, Issue 4 2008
    Chee-Yong Chua
    Abstract The feasibility of using ultrasonication in combination with the Fenton's reaction was investigated for treating cyan ink effluent. A two-step treatment process was developed,the first step was an ultrasound-assisted electro-oxidation, while the second was chemical oxidation through the addition of hydrogen peroxide. The use of electro-oxidation in the first step significantly reduced the amount of iron needed compared with the conventional Fenton's reaction, resulting in a 98% reduction in the amount of sludge produced. A simple technique based on refractive index measurements was introduced as a rapid way to quantify the amount of sludge produced. It was postulated that ultrasonication in the presence of iron (from electrolysis) in the first step converted the ink components into reaction intermediates which were more amenable to peroxide oxidation in the second step. These intermediates were quantified by ultra-violet absorption at wavelengths of 275,400 nm. The two-step treatment process was able to reduce the COD and copper contents in the ink waste water to within the discharge limit, which conventional Fenton's reaction was unable to meet for copper discharge. The same COD removal was also achieved in about half the time. Kinetics study performed to further understand the reaction mechanisms show second-order kinetics for both steps with activation energies of 18.2 and 20.4 kJ/mol for steps 1 and 2, respectively. On a étudié la possibilité de recourir à l'ultrasonification combinée à la réaction de Fenton pour traiter l'effluent d'encre de cyan. Un procédé de traitement en deux étapes a été mis au point: la première étape consiste en une électro-oxydation assistée par ultrasons, tandis que la seconde consiste en une oxydation chimique par ajout de peroxyde d'hydrogène. Le recours à l'électro-oxydation dans la première étape réduit significativement la quantité de fer requis comparé à la réaction de Fenton classique, entraînant une réduction de 98% de la quantité de suspension produite. Une technique simple basée sur des mesures d'indice de réfraction a été introduite comme une façon rapide d'établir la quantité de suspension produite. On a posé comme postulat que l'ultrasonification en présence de fer (de l'électrolyse) dans la première étape convertit les composantes de l'encre en des intermédiaires de réaction qui étaient plus propices à l'oxydation du peroxyde dans la seconde étape. Ces intermédiaires ont été quantifiés par l'absorption des ultraviolets à des longueurs d'ondes de 275 nm à 400 nm. Ce procédé de traitement en deux étapes a permis de réduire la DCO et les teneurs en cuivre dans l'eau usée de l'encre pour les amener à la limite des normes de rejet, ce que la réaction de Fenton classique n'a pu permettre de réaliser pour le cuivre. Le même retrait de DCO a été également réalisé dans un temps inférieur de 50%. L'étude de cinétique effectuée pour mieux comprendre les mécanismes de réaction montre une cinétique de second ordre pour les deux étapes avec des énergies de désactivation de 18,2 et 20,4 kJ/mol pour les étapes 1 et 2, respectivement. [source]