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Articoli di riviste sul tema "Gomme de T"

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Koranteng, B. A., A. B. Omojola, O. R. Awodoyin e A. O. Adediran. "Physicochemical and sensory characteristics of soft cheese as affected by different salt levels". Nigerian Journal of Animal Production 48, n. 5 (10 novembre 2021): 124–34. http://dx.doi.org/10.51791/njap.v48i5.3193.

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Abstract (sommario):
Cheese, a nutrient-dense dairy food is very rich in protein and calcium. Salting during cheese production is an important step because its concentration is the major factor that influences the organoleptic quality especially flavour. In order to accommodate increasing demands for reduced-sodium cheese without compromising palatability and safety, it is therefore imperative to assess the effect of different salt levels that will produce good quality cheese. Raw milk was obtained from Gudali, Mali and Burkina cows at the Cattle and Dairy Research Station-Bodi, Ashanti, Ghana. There were five treatments and each consists of 1000 mL of milk, 2.5 mL of juice from Calotropis procera as coagulant and graded levels of salt (0, 4, 8, 12, 16g). Cheese was produced using standard procedure. Yield (%), proximate composition (%) mineral contents (sodium, chlorine, calcium, phosphorus) and texture profile analysis (adhesiveness, chewiness, cohesiveness elasticity, firmness, gumminess resilience was assessed on freshly prepared cheese. The result revealed that cheese pH slightly increased as salt concentration increased. The moisture of T (59.47) and T (58.70) 2 3 were not significantly (P>0.05) different but these were different from T (54.67), T (56.60), 1 4 T (50.37). The crude protein contents of T (16.36) and T (15.68) were significantly higher 5 3 1 (P<0.05) than T2 (13.90), T4 (10.77) and T5 (10.32). The fat contents of T4 (14.41) and T5 (17.28) were significantly higher (P<0.05) compared with others. The yield (33.64) and calcium content (1.49) of T and phosphorus content (2.35) of T were significantly higher 3 5 (P<0.05) than others. The texture profile analysis indicated that the adhesiveness, cohesiveness and resilience of cheese T and T were significantly lower (P<0.05); while the 4 5 chewiness, elasticity, firmness and gumminess of T and T were significantly higher 4 5 (P<0.05). The study revealed that cheese with salt inclusion level of 8g (T ) possesses the 3 characteristics of a good quality cheese. Le fromage, un aliment laitier riche en nutriments, est très riche en protéines et en calcium. Le salage lors de la fabrication du fromage est une étape importante car sa concentration est le facteur majeur qui influence la qualité organoleptique en particulier la saveur. Afin de répondre à la demande croissante de fromages à faible teneur en sodium sans compromettre l'appétence et la sécurité, il est donc impératif d'évaluer l'effet des différents niveaux de sel qui produiront un fromage de bonne qualité. Le lait cru a été obtenu à partir de vaches Gudali, Mali et Burkina à la Bovin et Station de recherche laitière-Bodi, Ashanti, Ghana. Il y avait cinq traitements et chacun se compose de 1000 ml de lait, 2,5 ml de jus de Calotropisprocera comme coagulant et des niveaux gradués de sel (0, 4, 8, 12, 16 g). Le fromage a été produit en utilisant une procédure standard. L'analyse du rendement (%), de la composition approximative (%) des teneurs en minéraux (sodium, chlore, calcium, phosphore) et du profil de texture (adhésivité, mastication, cohésion, élasticité, fermeté, résistance à la gomme a été évaluée sur du fromage fraîchement préparé. Le résultat a révélé que le pH du fromage légèrement augmenté avec l'augmentation de la concentration en sel. L'humidité de T2 (59,47) et T3 (58,70) n'étaient pas significativement différentes (P>0,05) mais elles étaient différentes de T1 (54,67), T4 (56,60), T5 (50,37). les teneurs en protéines de T3 (16,36) et T1 (15,68) étaient significativement plus élevées (P<0,05) que celles de T2 (13,90), T4 (10,77) et T5 (10,32) Les teneurs en graisses de T4 (14,41) et T5 (17,28) étaient significativement plus élevé (P<0,05) par rapport aux autres. Le rendement (33,64) et la teneur en calcium (1,49) de T3 et la teneur en phosphore (2,35) de T5 étaient significativement plus élevés (P<0,05) que les autres. L'analyse du profil de texture a indiqué que le l'adhésivité, la cohésion et la résilience des fromages T4 et T5 étaient significativement plus faibles (P<0,05 ); tandis que la mastication, l'élasticité, la fermeté et la gomme des T4 et T5 étaient significativement plus élevées (P < 0,05). L'étude a révélé que le fromage avec un taux d'inclusion de sel de 8g (T3) possède les caractéristiques d'un fromage de bonne qualité.
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Roldan, Hector A., Andrew Robert Brown, Jane Radey, John C. Hogenbirk e Lisa Rosalie Allen. "Enhanced recovery after surgery reduces length of stay after colorectal surgery in a small rural hospital in Ontario". Canadian Journal of Rural Medicine 28, n. 4 (2023): 179–89. http://dx.doi.org/10.4103/cjrm.cjrm_71_22.

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Introduction: Enhanced recovery after surgery (ERAS) programmes include pre-operative, intraoperative and post-operative clinical pathways to improve quality of patient care while reducing length of stay (LOS) and readmission. This study assessed the feasibility and outcomes of an ERAS protocol for colorectal surgery implemented over 2 years in a small, resource-challenged rural hospital. Methods: A prospective cohort study used retrospectively matched controls to assess the effect of ERAS on LOS in patients undergoing colorectal surgery in a small rural hospital in northern Ontario, Canada. ERAS patients were matched to two patients in the control group based on diagnosis, age and gender. Patients had open or laparoscopic colorectal surgeries, with those in the intervention group treated per ERAS protocol and given instructions on pre- and post-operative self-care. Results: Most of the 47 ERAS patients recruited to the study reported adherence to ERAS protocols before surgery. Adherence to protocol was strongest for chewing gum in the days after surgery. Most patients were sitting in a chair for their afternoon meal by the 1st day and most were walking down the hallway by the 2nd day. The control group had significantly higher (P < 0.001) malignant neoplasm of the colon (C18, 69% vs. 35%) and significantly lower malignant neoplasm of the rectum (C20, 0% vs. 5%). The control group had an average ln-transformed LOS that was significantly longer (exponentiated as 1.7 days) than ERAS patients (t-test, P < 0.001). Conclusion: This study found that ERAS could be implemented in a small rural hospital and provided evidence for a reduced LOS of approximately 2 days. Introduction: Les programmes de réhabilitation améliorée après chirurgie (RAAC) comprennent des itinéraires cliniques préopératoires, peropératoires et postopératoires visant à améliorer la qualité des soins aux patients tout en réduisant la durée du séjour et les réadmissions. Cette étude a évalué la faisabilité et les résultats d’un protocole de RAAC pour la chirurgie colorectale mis en œuvre pendant deux ans dans un petit hôpital rural aux ressources limitées. Méthodes: Une étude de cohorte prospective a utilisé des témoins appariés pour évaluer l’effet de la RAAC sur la durée du séjour des patients subissant une chirurgie colorectale dans un petit hôpital rural du nord de l’Ontario, au Canada. Les patients RAAC ont été appariés à deux patients du groupe témoin sur la base du diagnostic, de l’âge et du sexe. Les patients ont subi une chirurgie colorectale ouverte ou laparoscopique, et ceux du groupe d’intervention ont été traités selon le protocole de RAAC et ont reçu des instructions sur les soins auto-administrés pré et postopératoires. Résultats: La plupart des 47 patients RAAC recrutés pour l’étude ont déclaré adhérer aux protocoles de RAAC avant l’intervention chirurgicale. L’adhésion au protocole a été la plus forte pour la gomme à mâcher dans les jours qui ont suivi l’opération. La plupart des patients étaient assis sur une chaise pour le repas de l’après-midi dès le premier jour et la plupart marchaient dans le couloir dès le deuxième jour. Le groupe témoin présentait un taux significativement plus élevé (P < 0,001) de néoplasme malin du côlon (C18, 69% contre 35%) et un taux significativement plus faible de néoplasme malin du rectum (C20, 0% contre 5%). Le groupe de contrôle avait une durée moyenne de séjour transformée en Ln significativement plus longue (exponentielle de 1,7 jours) que les patients RAAC (test t, P < 0,001). Conclusion: Cette étude a montré que la RAAC pouvait être mise en œuvre dans un petit hôpital rural et a fourni des preuves d’une réduction de la durée de séjour d’environ deux jours.
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Crew Dennis, Manzo, Egunsola, A. O. E e Sarki, R.A. "Appraising Effective Utilization of Instructional Materials for Teaching and Learning of Agricultural Science in Senior Secondary Schools in Gombe State, Nigeria". Edunity : Kajian Ilmu Sosial dan Pendidikan 2, n. 3 (25 marzo 2023): 377–92. http://dx.doi.org/10.57096/edunity.v2i3.73.

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Abstract (sommario):
The purpose of this study was to appraise the effective utilization of instructional materials for teaching and learning of Agricultural Science in senior secondary schools in Gombe State, Nigeria. The study which was descriptive survey research was conducted in Gombe State and was guided by three research questions and three null hypotheses. The population of the study was 406 respondents involving 184 agricultural science teachers and 222 school administrators from the 74 senior secondary schools in Gombe State. The sample size of the study was 196 respondents determined using Krejcie and Morgan (1970) sample size table. A structured questionnaire was used for data collection. 0.84 reliability index was obtained from the trial test of QEUIMTLASSSS using Cronbach Alpha. Data collected for the study was analyzed using Mean statistics and t-test. Findings of the study revealed among others that Out of the 26 items listed, only 16 items namely: school farm, watering cans, plant lifters, planting hoes, etc. were functional for teaching and learning of Agricultural Science in secondary schools in Gombe State; while Instructional materials such as school farm, watering cans, plant lifters, and shovels were highly utilized for teaching and learning of Agricultural Science in Secondary Schools in Gombe State. It was recommended, Secondary Schools' administrators in Gombe State should reward teachers who form good habit of maintaining available instructional materials in the school; Ministry of Education in Gombe State should increase supervision of lessons and review teachers' workload in order for teacher to be able to examine their students' academic progress and performance as the use of instructional materials have significant effect on the students' academic performance.
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Bussotti, Lucca. "The Southern African Development Community Treaty-Nexus; Integration in the Southern African Development Community Region". Revista de Estudos AntiUtilitaristas e PosColoniais 13 (31 gennaio 2024): 1–4. http://dx.doi.org/10.51359/2179-7501.2023.261450.

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The Southern African Development Community Treaty-Nexus; Integration in the Southern African Development Community Region; Edts: K. Gombe Adar, D. Mpabanga, K. Lotshwao, T. Molokwane, N. Musekiwa. London: Lexington Book, 2023.
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Ishaka, Yahaya. "Effectiveness of Cognitive Restructuring Counselling Technique in Managing Anxiety Among Couples with Infertility Challenges in Gombe State, Nigeria". Kashere Journal of Education 2, n. 2 (15 marzo 2022): 158–64. http://dx.doi.org/10.4314/kje.v2i2.20.

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This study investigated the effectiveness of cognitive restructuring counselling technique in managing anxiety among couples with infertility challenges in Gombe State, Nigeria. The population of this study was seventy-six (76) couples of reproductive age with infertility challenges that were registered and receiving infertility treatment at the two Government owned hospitals selected for this study. These are: Federal teaching hospital, Gombe and Specialist Hospital Gombe. Forty-two (42) patients accessing infertility treatment from Federal teaching hospital and thirty-four (34) patients accessing infertility treatment from specialist hospital Gombe (i.e. 42+34 = 76). Thirty-eight (38) couples were selected to participate in the study. The researcher employed quasi-experimental pre-test/post-test and control group design, in which selected couples were assigned to two experimental groups. The experimental group were treated with cognitive restructuring counselling tecnique while the control group didn’t receive any treatment. The treatments were carried out within eight weeks of counselling sessions. Group counselling method was employed in the study. Each of the subjects was administered with pre-test/post-test research instrument using Beck Anxiety Inventory (BAI) Two research objectives and two research hypotheses were formulated. The data collected were analyzed using dependent sample t-test to test hypothesis 1 and independent t-test was used to test hypothesis 2 at 0.05 level of significance. Results from data analysis revealed that cognitive restructuring counselling technique was effective in managing anxiety among couples with infertility challenges. It was also recommended that cognitive restructuring should be used in managing anxiety level of couples faced with infertility challenges in various health centres.
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C., Ezugu L., Philip S e Isaac J. I. "Tools and Equipment Utilization in Radio Television and Global System Mobile Servicing In Vocational Training Centres in Gombe State, Nigeria". Journal of Electronics,Computer Networking and Applied Mathematics, n. 31 (2 gennaio 2023): 16–26. http://dx.doi.org/10.55529/jecnam.31.16.26.

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Determining the tools and equipment use in Radio Television and Global System Mobile Servicing at Vocational Centers in Gombe State, Nigeria, was the major goal of the study. The study used a descriptive survey research approach and was carried out in Gombe State, Nigeria. 55 respondents made up the study's population, including 42 teachers and 13 administrators (principals). There was no sampling because the population was of a manageable size, hence the entire population was employed for the study. A structured questionnaire called the "Tools and Equipment Utilization Questionnaire (TEUQ)" was the instrument used to gather the data. The instrument was evaluated by three professionals, and Cronbach Alpha yielded a reliability value of 0.72. The mean statistics were utilized to answer the research questions, and the null hypotheses were tested using a t-test with a 0.05 threshold of significance. Equipment in RTV and GSM servicing trade workshops at the Vocational Training Centers in Gombe State, including workstations, multimeters-digital, multimeters-analog, Booster meters, white lights, various phone panels, Tornados (soft wire boxes), television training modules, probe/logic pulsar, oscilloscopes, pattern generators, picture tube testers, isolation transformers, vector scopes, signal strength meters, black and white television, colored television, and TV. The study also showed that the tools used in the RTV and GSM servicing Trade workshop at the Vocational Training Centers in Gombe State, including (Set of flat Screwdrivers, (large, medium, and small), Asterics, a Set of Allen keys, Set of Star Screwdrivers, Set of Spanners and Soldering Iron) is sufficient. It was suggested that in order for the schools to succeed, the Gombe State Ministry of Education should supply them with the necessary training materials and apparatus. Additionally, the government has to provide all trainers with greater technical training so they can use new technology in the workshop.
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Ibanga, Isaac John, Philip Sunday e Hyelaiti Raphael. "Methodological Skills Required By Instructors in Radio Television and Global System Mobile Servicing in Vocational Centers in Gombe State, Nigeria". Journal of Electronics,Computer Networking and Applied Mathematics, n. 25 (20 agosto 2022): 23–33. http://dx.doi.org/10.55529/jecnam.25.23.33.

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The study's primary goal was to evaluate the methodological skills required by instructors in Radio Television and Global System Mobile Servicing in Vocational Centers in Gombe State, Nigeria. The study used a descriptive survey research approach and was carried out in Gombe State, Nigeria. 55 respondents made up the study's population, including 42 teachers and 13 principals. There was no sampling because the population was of a manageable size, hence whole-population-sampling technique was employed for the study. The structured questionnaire "Questionnaire on the Appraisal of Skills Required by Instructors (QASRI)" designed by the researchers served as the instrument for data collection. The instrument was validated by three professionals, and Cronbach Alpha yielded a reliability value of 0.72. The mean statistics were utilized to answer the research questions, and the null hypotheses were tested using the t-test at a significance threshold of 0.05. According to the statistics, 51.2% of the respondents in Nigeria meet the minimal teaching standards, while 41.8% do not. Additionally, the study found that although teachers in the Radio Television and Global System Mobile Service trade in Vocational Centers in Gombe State, Nigeria, has some abilities in the profession, much more is still needed. It was suggested that the Gombe State Ministry of Education make sure that instructors appointed to vocational centers are well qualified and hold at least the Nigerian minimum for instructors. Additionally, the government should provide on-the-job training for instructors at vocational centers so they may develop more technical skills for efficient teaching and learning.
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Okpanachi, G. O., F. Yahya, J. A. Bwala, S. A. Maikifi e I. V. Emenike. "Assessment of the Quality of Diclofenac Tablets Marketed in Gombe Metropolis, Nigeria". Journal of Basic and Social Pharmacy Research 2, n. 4 (2022): 46–56. http://dx.doi.org/10.52968/27454099.

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Background: Diclofenac is a non-steroidal anti-inflammatory drug (NSAID) that inhibits the enzyme cyclo-oxygenase and decreases the synthesis of prostaglandins. Diclofenac tablet is one of the commonly used NSAID marketed in Gombe metropolis. Objectives: The study is aimed at assessing the quality of different brands of diclofenac tablets (50 mg) sold at Pharmacies and Patent medicine shops (PMS). Method: Ten diclofenac tablet brands were obtained from registered Pharmacy shops and labelled “A to J” while ten brands from PMS were labelled “K to T”. The quality of the tablets was evaluated using official and non-official parameters such as uniformity of weight; thickness; diameter; crushing strength (CS); friability (FR); disintegration time (DT), wetting time, dissolution testing and tablet content uniformity. Results: Brands A, E, J from Pharmacies and K, N, Q, R from PMS had mean CS within the range of 4-7 kgF. Others had CS > 7 kgF. The FR values of all the brands except F and T were <1.0 %. All the tablet brands except Q disintegrated in <15 min. All the brands obtained from pharmacies and PMS released >75 % of the drug within 30 min except brands G and T. Conclusion: Almost all the brands were of good quality because they passed the prescribed tests. But only a few tablet brands most especially G and T that showed slightly dissimilar results when compared with the BP specifications.
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Usifoh, Nnamdi, Toby Yak, Ivy Dooga, Raymond Dankoli, Olufemi Ajumobi, Adewole Adefisoiye e Oluwasegun Joel Adegoke. "Measles Data Reporting in the District Health Information System: A Case Study of Gombe State". Global Journal of Health Science 11, n. 11 (17 settembre 2019): 109. http://dx.doi.org/10.5539/gjhs.v11n11p109.

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BACKGROUND: The District Health Information System (DHIS2) is a modular, cloud-based data management system designed for use in integrated health information systems. In Nigeria, it serves as the repository for routine health data, including measles. A first dose of measles is given routinely in most countries, however, for a country to include a second dose of measles in the routine immunization schedule, it must meet certain criteria set by the World Health Organization (WHO). Unfortunately, Nigeria falls into the category of countries that haven&rsquo;t met the criteria. Despite this, MCV2 data can be seen on the DHIS2 platform. Data from DHIS2 also shows that Gombe State has the highest number of health facilities that reported MCV2 data at least once from 2015 to 2017. The aim of the study was to determine the reasons for the MCV2 reporting on DHIS2 platform for Gombe State. METHOD: We conducted a cross-sectional study among health workers in selected health facilities and LGA RI Officers at the LGA level in Gombe State. Health facility registers were reviewed, and data consistency was ascertained. We reviewed and conducted secondary data analysis of MCV2 data for Gombe State from January 2015 to December 2017. RESULTS: Of the 22 health facilities assessed, 14 health facilities (12 public and 2 private) reported offering MCV2 during the health facility-level interviews. At the LGA level, 5 LGAs out of the 11 LGAs reported during the LGA-level interviews that a second dose of measles is part of the RI schedule in their respective LGAs. For the 6 LGAs that reported not offering a second dose of measles as part of the RI schedule, 3 LGAs identified data entry error as the possible reason for having MCV2 data in the DHSI2 platform while the remaining 3 LGAs reported that the MCV2 data in the DHIS2 platform can be attributed to recording children who didn&rsquo;t receive a first dose of measles at 9 months but received at 18&ndash;23 months as second dose of measles. CONCLUSION: Data entry error and knowledge gap on how to record measles data were identified factors responsible for MCV2 data on the DHIS2 platform. There is a need for targeted interventions towards improving the quality of RI data in Nigeria.
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Ngwakwe, Chinyere Catherine, Nwosu Chinedu Anthony e Opara David Kalu. "Students’ Perception on the Use of Virtual Learning as a New Innovation of Learning in Tertiary Institutions for Global Best Practices in Gombe State". International Journal of Research and Innovation in Social Science VII, n. V (2023): 482–93. http://dx.doi.org/10.47772/ijriss.2023.70540.

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This study examined the students’ perception on the use of virtual learning as a new innovation of learning in tertiary institutions for global best practices in Gombe State. Two research questions guided the study and two null hypotheses were also tested. Descriptive survey design was adopted. The population comprised 350 final year and 515 penultimate students in five tertiary institutions in Gombe State. A sample size of 250 students was selected for the study using simple random sampling technique. A structured and validated questionnaire on four-point rating scale containing 48 items was used for data collection. Cronbach Alpha method was used to establish the reliability of the instrument which yielded coefficients of 0.87, 0.80, 0.68 and 0.84 for the different clusters with an overall coefficient of 0.79. Data collected were analyzed using mean and standard deviation to answer the research questions while t-test was used to test the hypotheses at 0.05 level of significance. The analysis was carried out using SPSS version 23.0. Findings revealed that not all the students have access to virtual learning services, virtual learning services were not adequately available for some students of tertiary institutions especially those living in rural areas. Students’ competency in internet usage was fair and that virtual learning service delivery is constrained by a lot of factors. Therefore, it is recommended that urgent steps should be taken to provide technical resources and improvement in internet connection for ensuring uninterrupted online education in Gombe State to fulfill the education needs of tertiary institution students.
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Tesi sul tema "Gomme de T"

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Fanwa, nzokou Michele. "Extractiοn de la gοmme de triumfetta cοrdifοlia (Μalvaceae) : caractérisatiοn et valοrisatiοn". Electronic Thesis or Diss., Normandie, 2024. http://www.theses.fr/2024NORMLH08.

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Les polysaccharides sont omniprésents dans le quotidien de l’homme à travers leur implication dans des domaines vitaux dont l’alimentation, la cosmétique, les domaines pharmaceutique et biomédicaux (…) où ils assurent des fonctions très variées. Ce caractère versatile couplé à leur grande disponibilité, leur caractère biocompatible et biodégradable, avec une toxicité limitée, et leurs propriétés biologiques recherchées, en font des ingrédients de prédilection pour de nombreuses industries, ce qui explique leur forte demande au détriment d’ingrédients moins recommandables à l’exemple de polymères pétrosourcés.Ce travail s’inscrit dans la recherche d’alternatives vertes pouvant valablement substituer les polymères synthétiques et contribuer à satisfaire la demande grandissante en ingrédients naturels pour de nombreuses industries intéressées à développer des formulations limitant l’usage d’ingrédients pétrosourcés. L’une des stratégies pour y parvenir consiste à explorer de ‘‘nouvelles’’ ressources disponibles de la biomasse au profil recherché. L’un des candidats potentiels est la gomme de T. cordifolia, une ressource aux propriétés singulières, utilisée depuis de nombreuses générations dans l’alimentation et la médecine Africaine, mais encore sous-étudiée et sous-exploitée.Le but de ce travail était d’apporter une meilleure connaissance et compréhension des propriétés de la gomme de T. cordifolia, puis de démontrer par la suite son potentiel de valorisation. Pour cela il a été essentiel de développer dans un premier temps une méthode d’extraction efficace et reproductible, capable de produire une gomme de haute pureté et à bon rendement, d’effectuer ensuite une série de caractérisations chimiques, physico-chimiques et rhéologiques, avant de mener enfin des essais de valorisation. De cette manière, nous avons pu accéder aux propriétés intrinsèques de la gomme à l’exemple de la composition chimique et monosaccharidique, la viscosité intrinsèque, les régimes de concentrations, les propriétés viscoélastiques en fonction de divers paramètres (concentration de gomme, température, pH, nature et concentration saline) et avons par la suite démontré son potentiel comme émulsifiant et stabilisant d’émulsions dès les faibles concentrations, un potentiel dû à la fois à son excellente capacité d’abaisser la tension superficielle de l’eau, à sa capacité de texturation marquée, ainsi qu’à son caractère polyélectrolyte.En somme, de par ses propriétés intrinsèques et fonctionnelles très marquées, la gomme de T. cordifolia présente un certain nombre de propriétés, en solution comme en émulsion, qui en font un candidat à fort potentiel de valorisation comme ingrédient multifonctionnel pour la formulation d’émulsions vertes et innovantes
Polysaccharides are ubiquitous in everyday human life, through their involvement in vital fields such as food, cosmetics, pharmaceuticals and biomedicine (...), where they perform a wide variety of functions. Their versatility, combined with their availability, biocompatibility and biodegradability, with limited toxicity, and their relevant biological properties, make them the ingredients of choice for many industries, which explains their high demand to the detriment of less recommendable ingredients such as petro-based polymers.This work focuses on the search for green alternatives that can validly replace synthetic polymers and help meet the growing demand for natural ingredients from many industries interested in developing formulations that limit the use of petroleum-based ingredients. One strategy for achieving this is to explore "new" biomass resources with the desired profile. One potential candidate is T. cordifolia gum, a resource with singular properties that has been used for many generations in African food and medicine, but is still under-studied and under-exploited.The aim of this work was to gain a better knowledge and understanding of the properties of T. cordifolia gum, and then to demonstrate its valuation potential. To achieve this, it was essential to develop an efficient and reproducible extraction method capable of producing high-purity gum with good yields, then to carry out a series of chemical, physico-chemical and rheological characterizations, before proceeding with valorization trials. In this way, T. cordifolia gum's intrinsic properties, such as chemical and monosaccharide composition, intrinsic viscosity, concentration regimes and viscoelastic properties as a function of various parameters (gum concentration, temperature, pH and salt concentration) were elucidated, and its potential as emulsifier and stabilizer in oil-in-water emulsions was demonstrated at very low concentrations; a potential due to its excellent ability to lower the surface tension of water, its marked texturizing ability and its polyelectrolyte nature.All in all, the relevant intrinsic and functional properties of T. cordifolia gum, both in solution and in emulsion, make it a very promising candidate for use as a multifunctional ingredient in the formulation of innovative green emulsions
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Oliveira, Edson Leandro de. "Étude cinétique et modélisation de la réaction d'hydroformylation catalysée par le complexe [Rh/2(mu-S-t-Bu)/2(CO)(PPh/3)/2] et son homologue supporté sur résine". Toulouse, INPT, 1992. http://www.theses.fr/1992INPT040G.

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Abstract (sommario):
L'etude cinetique de l'hydroformylation basse pression de l'oct-1-ene catalysee par le compose rh2(-s-t-bu)2(co)2(pph3)2 a permis de montrer que les courbes de la vitesse de reaction en fonction du degre d'avancement sont extremement sensibles dans leur forme complexe a la composition du melange h#2/co a la concentration initiale en alcene, a la concentration en precurseur du rhodium. Un modele empirique adapte de celui propose par chaudhari pour le complexe hrh(co)(pph#3)#3 ainsi qu'un mecanisme reactionnel ont permis d'ecrire une equation de vitesse rendant bien compte de l'experience. En outre, la deuxieme approche valide le cycle catalytique dans lequel les especes intermediaires demeurent dinucleaires. Le greffage de ce precurseur sur resine styrene-divinylbenzene a ete mis au point. L'etude cinetique entreprise egalement ici, a permis d'effectuer une premiere approche d'une reaction realisee dans un reacteur parfaitement agite en continu
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