Pub Date : 2022-03-20DOI: 10.48141/sbjchem.21scon.30_abstract_ferreira.pdf
Lucas L. Ferreira, Amanda Alfeld Belegote, L. Silva, Steffany Souza Cabral, P. N. dos Santos
Canine visceral leishmaniasis (CVL) is a disease with a great impact on public health in Brazil due to its zoonotic potential. One of the biggest challenges in controlling the disease is the fact that its main reservoir in urban areas is the domestic dog, and thus, it is a source of infection that lives very close to the human being. This study aimed to determine the seroprevalence of L. chagasi and the symptoms of CVL present in dogs living near a human case confirmed by the Municipal Health Department of the municipality of Vassouras. Blood samples were collected from the cephalic vein of 14 resident dogs within a radius of 150 meters from a confirmed human case. This collected material was submitted to the DPP screening test, and the positive samples were submitted to the ELISA confirmatory test. Information was also obtained through questionnaires about the presence of the disease's clinical signs. Of the 14 animals tested in the DPP, only 4 were positive in the screening test, and all presented negative results in the ELISA confirmatory test. Of the 14 dogs, 4 had symptoms. Of these, 2 presented skin lesions, and 1 animal showed cough, while the last one exhibited vomiting. It is concluded that the DPP screening test for CVL is a practical and easy to handle method, although it requires attention due to the possibility of cross-reaction with other etiological agents in dogs. The human case is probably a result of a non-autochtone infection. Therefore, asymptomatic dogs should be under disease surveillance since these hosts also act as a source of infection for vector insects.
{"title":"SEROPREVALENCE AND CLINICAL MANIFESTATIONS OF DOMICILED DOGS (CANIS LUPUS FAMILIARIS) CLOSE TO A HUMAN CASE OF VISCERAL LEISHMANIASIS","authors":"Lucas L. Ferreira, Amanda Alfeld Belegote, L. Silva, Steffany Souza Cabral, P. N. dos Santos","doi":"10.48141/sbjchem.21scon.30_abstract_ferreira.pdf","DOIUrl":"https://doi.org/10.48141/sbjchem.21scon.30_abstract_ferreira.pdf","url":null,"abstract":"Canine visceral leishmaniasis (CVL) is a disease with a great impact on public health in Brazil due to its zoonotic potential. One of the biggest challenges in controlling the disease is the fact that its main reservoir in urban areas is the domestic dog, and thus, it is a source of infection that lives very close to the human being. This study aimed to determine the seroprevalence of L. chagasi and the symptoms of CVL present in dogs living near a human case confirmed by the Municipal Health Department of the municipality of Vassouras. Blood samples were collected from the cephalic vein of 14 resident dogs within a radius of 150 meters from a confirmed human case. This collected material was submitted to the DPP screening test, and the positive samples were submitted to the ELISA confirmatory test. Information was also obtained through questionnaires about the presence of the disease's clinical signs. Of the 14 animals tested in the DPP, only 4 were positive in the screening test, and all presented negative results in the ELISA confirmatory test. Of the 14 dogs, 4 had symptoms. Of these, 2 presented skin lesions, and 1 animal showed cough, while the last one exhibited vomiting. It is concluded that the DPP screening test for CVL is a practical and easy to handle method, although it requires attention due to the possibility of cross-reaction with other etiological agents in dogs. The human case is probably a result of a non-autochtone infection. Therefore, asymptomatic dogs should be under disease surveillance since these hosts also act as a source of infection for vector insects.","PeriodicalId":20606,"journal":{"name":"Proceedings of the SOUTHERN BRAZILIAN JOURNAL OF CHEMISTRY 2021 INTERNATIONAL VIRTUAL CONFERENCE","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2022-03-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85143651","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-03-20DOI: 10.48141/sbjchem.21scon.33_abstract_borges.pdf
Gabriel Rübensam, Henrique Borges
2,5-hexanedione is the main metabolite of hexane and methyl butyl ketone excreted into urine and is currently used to estimate the human exposure levels to these solvents in professional environments. In Brazil, occupational exposure is regulated by a national control program (PCMSO) and applied to public and private organizations that hire your employees according to the actual Brazilian legislation. In the present work, we validated a methodology based on a gas chromatography−flame ionization detector (GC-FID) for the quantification of 2,5-hexanedione in urine to attend the new occupational limit of urinary 2,5-hexanedione, established by a recent revision of the Brazilian legislation, which reduced this limit from 5.0 to 0.5 mg/L. Before GC-FID analysis, sample treatment was based on a simple liquid-liquid extraction with dichloromethane. Considering that there is no specific validation guide for occupational purposes, the adopted validation process was performed using a “fit-for-purpose” approach based on different guides, including FDA bioanalytical method validation, European Commission Decision 2002-657-EC, and ANVISA Guidelines RDC 166/2017. After method optimization, the performance characteristics determined by the present validation study were considered satisfactory and demonstrate the method suitability for the routine analysis in the Brazilian PCMSO, including CCα and CCβ values, which are used to avoid the presentation of false-positive and false-negative results. Intra and interday reproducibility were below 2.66, and 4.08 % and analyte recoveries were above 95.4% for three evaluated levels. The limits of detection and quantification were 0.05 and 0.17, respectively. To our knowledge, this is the first application of CCα and CCβ approaches in an analytical method intended for occupational purposes, which are important to know when a sample is out or following the legislation. Then real samples were analyzed herein, and none presented 2,5-hexanedione above the required limits.
{"title":"VALIDATION OF A GC-FID METHODOLOGY FOR THE DETERMINATION OF 2,5-HEXANEDIONE IN URINE","authors":"Gabriel Rübensam, Henrique Borges","doi":"10.48141/sbjchem.21scon.33_abstract_borges.pdf","DOIUrl":"https://doi.org/10.48141/sbjchem.21scon.33_abstract_borges.pdf","url":null,"abstract":"2,5-hexanedione is the main metabolite of hexane and methyl butyl ketone excreted into urine and is currently used to estimate the human exposure levels to these solvents in professional environments. In Brazil, occupational exposure is regulated by a national control program (PCMSO) and applied to public and private organizations that hire your employees according to the actual Brazilian legislation. In the present work, we validated a methodology based on a gas chromatography−flame ionization detector (GC-FID) for the quantification of 2,5-hexanedione in urine to attend the new occupational limit of urinary 2,5-hexanedione, established by a recent revision of the Brazilian legislation, which reduced this limit from 5.0 to 0.5 mg/L. Before GC-FID analysis, sample treatment was based on a simple liquid-liquid extraction with dichloromethane. Considering that there is no specific validation guide for occupational purposes, the adopted validation process was performed using a “fit-for-purpose” approach based on different guides, including FDA bioanalytical method validation, European Commission Decision 2002-657-EC, and ANVISA Guidelines RDC 166/2017. After method optimization, the performance characteristics determined by the present validation study were considered satisfactory and demonstrate the method suitability for the routine analysis in the Brazilian PCMSO, including CCα and CCβ values, which are used to avoid the presentation of false-positive and false-negative results. Intra and interday reproducibility were below 2.66, and 4.08 % and analyte recoveries were above 95.4% for three evaluated levels. The limits of detection and quantification were 0.05 and 0.17, respectively. To our knowledge, this is the first application of CCα and CCβ approaches in an analytical method intended for occupational purposes, which are important to know when a sample is out or following the legislation. Then real samples were analyzed herein, and none presented 2,5-hexanedione above the required limits.","PeriodicalId":20606,"journal":{"name":"Proceedings of the SOUTHERN BRAZILIAN JOURNAL OF CHEMISTRY 2021 INTERNATIONAL VIRTUAL CONFERENCE","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2022-03-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84848754","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-03-20DOI: 10.48141/sbjchem.21scon.32_abstract_argon.pdf
Raiza Argon Passos, E. C. R. Roier, L. P. Gomes, R. V. Serapião, G. M. Gomes
Since 1986, the use of embryo transfer has gained prominence in the equine industry, allowing the increase in the number of descendants of genetically superior donors, competition mares, foals, and mares considered subfertile. The success of an embryo transfer program is directly related to the rate of embryonic recovery by mare, which is characterized by the percentage of embryos collected by uterine lavage. However, the recovery rate can be influenced by several factors, type of donor used, age, day of collection, and physical activity. Considering the advancement of biotechnology and the growing need for research in the area of equine embryo transfer, the present work aimed to study in Mangalarga marchador animals the effects of uterine lavage fractions on embryo recovery rates. The present study included 35 mares aged between 3 and 15 years, used as donors of clinically healthy embryos from an equestrian property in the southern region of Rio de Janeiro. Thus, 67 uterine washes were performed, where 67% of the embryos were recovered through different volumes of ringer's solution with sodium lactate. The embryo crops and transfers period was from September 2021 to January 2022. For statistical analysis of the data, the simple logistic regression test was used, where no significant difference (p<0.05) was observed in the embryo indices recovered on total crops (67) regarding fractions (F) 1 (43.2%), (F) 2 (14.9%) and (F) 3 (5.97%). Thefore, it can be concluded that there was no significant difference between the lavage fractions, however, more studies are needed with a larger sample of uterine washing.
{"title":"EFFECTS OF UTERINE LAVAGE FRACTIONS ON EMBRYO RECOVERY RATE IN MANGALARGA MARCHADOR MARES.","authors":"Raiza Argon Passos, E. C. R. Roier, L. P. Gomes, R. V. Serapião, G. M. Gomes","doi":"10.48141/sbjchem.21scon.32_abstract_argon.pdf","DOIUrl":"https://doi.org/10.48141/sbjchem.21scon.32_abstract_argon.pdf","url":null,"abstract":"Since 1986, the use of embryo transfer has gained prominence in the equine industry, allowing the increase in the number of descendants of genetically superior donors, competition mares, foals, and mares considered subfertile. The success of an embryo transfer program is directly related to the rate of embryonic recovery by mare, which is characterized by the percentage of embryos collected by uterine lavage. However, the recovery rate can be influenced by several factors, type of donor used, age, day of collection, and physical activity. Considering the advancement of biotechnology and the growing need for research in the area of equine embryo transfer, the present work aimed to study in Mangalarga marchador animals the effects of uterine lavage fractions on embryo recovery rates. The present study included 35 mares aged between 3 and 15 years, used as donors of clinically healthy embryos from an equestrian property in the southern region of Rio de Janeiro. Thus, 67 uterine washes were performed, where 67% of the embryos were recovered through different volumes of ringer's solution with sodium lactate. The embryo crops and transfers period was from September 2021 to January 2022. For statistical analysis of the data, the simple logistic regression test was used, where no significant difference (p<0.05) was observed in the embryo indices recovered on total crops (67) regarding fractions (F) 1 (43.2%), (F) 2 (14.9%) and (F) 3 (5.97%). Thefore, it can be concluded that there was no significant difference between the lavage fractions, however, more studies are needed with a larger sample of uterine washing.","PeriodicalId":20606,"journal":{"name":"Proceedings of the SOUTHERN BRAZILIAN JOURNAL OF CHEMISTRY 2021 INTERNATIONAL VIRTUAL CONFERENCE","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2022-03-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73337957","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-03-20DOI: 10.48141/sbjchem.21scon.28_abstract_ziliotto.pdf
Luis Henrique Carra Ziliotto, Isaac Newton Lima da Silva
Forensic investigators have widely used luminol for more than 90 years in the identification of blood in life crime scenes. When mixed with an alkaline solution and sprayed on a catalyst (iron present in blood hemoglobin), it reproduces a chemiluminescent reaction with a bluish color. As it is a presumptive blood test, the present study sought to demonstrate that only the photons emission is not a prerogative to attest that the result is indeed human blood. In this perspective, 24 samples of both liquid and solid substances that can easily be found in residences and potentially used by criminals to impair the interpretation of the investigator at the crime scene were prepared. Out of the total of the analyzed samples, there was a chemical reaction with sodium hypochlorite and wood varnish, proving the known understanding that some samples may cause interference in the examination with luminol.
{"title":"ANALYSIS OF FALSE-POSITIVE RESULTS AND THE REAL EFFECTIVENESS OF LUMINOL IN THE DETECTION OF BLOOD SPOTS.","authors":"Luis Henrique Carra Ziliotto, Isaac Newton Lima da Silva","doi":"10.48141/sbjchem.21scon.28_abstract_ziliotto.pdf","DOIUrl":"https://doi.org/10.48141/sbjchem.21scon.28_abstract_ziliotto.pdf","url":null,"abstract":"Forensic investigators have widely used luminol for more than 90 years in the identification of blood in life crime scenes. When mixed with an alkaline solution and sprayed on a catalyst (iron present in blood hemoglobin), it reproduces a chemiluminescent reaction with a bluish color. As it is a presumptive blood test, the present study sought to demonstrate that only the photons emission is not a prerogative to attest that the result is indeed human blood. In this perspective, 24 samples of both liquid and solid substances that can easily be found in residences and potentially used by criminals to impair the interpretation of the investigator at the crime scene were prepared. Out of the total of the analyzed samples, there was a chemical reaction with sodium hypochlorite and wood varnish, proving the known understanding that some samples may cause interference in the examination with luminol.","PeriodicalId":20606,"journal":{"name":"Proceedings of the SOUTHERN BRAZILIAN JOURNAL OF CHEMISTRY 2021 INTERNATIONAL VIRTUAL CONFERENCE","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2022-03-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73185435","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-03-20DOI: 10.48141/sbjchem.21scon.13_abstract_santos.pdf
Maricel Santos, A. Velez, I. Magario
Glycerol is a by-product in biodiesel synthesis, and its current market condition allows the possibility to transform into value-added compounds. In this work, the enzymatic esterification between glycerol and carboxylic acids of different molar weights was studied to obtain glycerides of industrial relevance. Therefore, eight different carboxylic acids were evaluated: formic, acetic, levulinic, caprylic, capric, lauric, stearic, and oleic. Immobilized lipase from Candida Antarctica was employed as a catalyst. Solvent-free reactions were carried out at 65 °C, 450 rpm, at a molar ratio of glycerol: carboxylic acid of 1:1 and a 1,6% enzyme concentration (based on reagents weight). Conversion of carboxylic acids was followed with time by titration. Under these conditions, acids from octanoic to oleic, which initially formed biphasic systems with glycerol, showed high conversions (68%-80%) and initial reaction rates in the same magnitude order. On the other hand, no enzymatic catalysis was observed with formic, acetic, and levulinic acids. Formic acid exhibited a higher rate and 58% of conversion without catalyst. However, for acetic and levulinic acids, conversion was low in uncatalyzed reactions. Then, for these acids, toluene was added as a reaction solvent. As a result, conversions and initial rates increased for these lighter acids, indicating the need for a non-polar media or a biphasic character to activate the enzyme.
{"title":"EFFECT OF MOLAR WEIGHT OF CARBOXYLIC ACIDS ON THE ENZYMATIC ESTERIFICATION OF GLYCEROL","authors":"Maricel Santos, A. Velez, I. Magario","doi":"10.48141/sbjchem.21scon.13_abstract_santos.pdf","DOIUrl":"https://doi.org/10.48141/sbjchem.21scon.13_abstract_santos.pdf","url":null,"abstract":"Glycerol is a by-product in biodiesel synthesis, and its current market condition allows the possibility to transform into value-added compounds. In this work, the enzymatic esterification between glycerol and carboxylic acids of different molar weights was studied to obtain glycerides of industrial relevance. Therefore, eight different carboxylic acids were evaluated: formic, acetic, levulinic, caprylic, capric, lauric, stearic, and oleic. Immobilized lipase from Candida Antarctica was employed as a catalyst. Solvent-free reactions were carried out at 65 °C, 450 rpm, at a molar ratio of glycerol: carboxylic acid of 1:1 and a 1,6% enzyme concentration (based on reagents weight). Conversion of carboxylic acids was followed with time by titration. Under these conditions, acids from octanoic to oleic, which initially formed biphasic systems with glycerol, showed high conversions (68%-80%) and initial reaction rates in the same magnitude order. On the other hand, no enzymatic catalysis was observed with formic, acetic, and levulinic acids. Formic acid exhibited a higher rate and 58% of conversion without catalyst. However, for acetic and levulinic acids, conversion was low in uncatalyzed reactions. Then, for these acids, toluene was added as a reaction solvent. As a result, conversions and initial rates increased for these lighter acids, indicating the need for a non-polar media or a biphasic character to activate the enzyme.","PeriodicalId":20606,"journal":{"name":"Proceedings of the SOUTHERN BRAZILIAN JOURNAL OF CHEMISTRY 2021 INTERNATIONAL VIRTUAL CONFERENCE","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2022-03-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78482931","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-03-20DOI: 10.48141/sbjchem.21scon.43_abstract_loredo.pdf
Francisco Antonio LOREDO NETO, Gabriela Santos Freitas, R. V. Serapião, Leticia Patrão Gomes, Thiago Luiz Pereira Marques
Beef cattle is one of the main sectors that drive the national economy, given the great generation of employment, presence in the consumer market, and exports. Among the various services generated, technical assistance to producers stands out, who work in several areas and, especially reproduction, which is a great ally to bovine production, because through it it is possible to monetize the creation with the use of reproducers with high fertility potential boosting livestock productivity. Therefore, the andrological evaluation in the sires is an important factor in selecting superior animals, seeking to improve the fertility of the herd. The present study aimed to analyze the sexual behavior of bulls of the Tabapuã breed, through the libido test, as part of the andrological examination. Ten young bulls of the Tabapuã breed were used, aged between 24-43 months, with an average weight of 375kg, without sexual experience. The libido test was performed from the contact of males with females in estrus and out of estrus to assess sexual interest. It was observed that half of the animals were classified with low libido (50%) and the other part with medium (30%) and high (20%) libido. In addition, it was observed that the most frequent sexual events were the identification of estrus. Finally, given the results of animals classified with low libido, it is suggested that sexual inexperience is correlated, and it is recommended to insert these cattle with high libido bulls so that they can observe the behaviors and gain experience.
{"title":"ANALYSIS OF THE SEXUAL BEHAVIOR OF BULLS OF THE TABAPUÃ BREED","authors":"Francisco Antonio LOREDO NETO, Gabriela Santos Freitas, R. V. Serapião, Leticia Patrão Gomes, Thiago Luiz Pereira Marques","doi":"10.48141/sbjchem.21scon.43_abstract_loredo.pdf","DOIUrl":"https://doi.org/10.48141/sbjchem.21scon.43_abstract_loredo.pdf","url":null,"abstract":"Beef cattle is one of the main sectors that drive the national economy, given the great generation of employment, presence in the consumer market, and exports. Among the various services generated, technical assistance to producers stands out, who work in several areas and, especially reproduction, which is a great ally to bovine production, because through it it is possible to monetize the creation with the use of reproducers with high fertility potential boosting livestock productivity. Therefore, the andrological evaluation in the sires is an important factor in selecting superior animals, seeking to improve the fertility of the herd. The present study aimed to analyze the sexual behavior of bulls of the Tabapuã breed, through the libido test, as part of the andrological examination. Ten young bulls of the Tabapuã breed were used, aged between 24-43 months, with an average weight of 375kg, without sexual experience. The libido test was performed from the contact of males with females in estrus and out of estrus to assess sexual interest. It was observed that half of the animals were classified with low libido (50%) and the other part with medium (30%) and high (20%) libido. In addition, it was observed that the most frequent sexual events were the identification of estrus. Finally, given the results of animals classified with low libido, it is suggested that sexual inexperience is correlated, and it is recommended to insert these cattle with high libido bulls so that they can observe the behaviors and gain experience.","PeriodicalId":20606,"journal":{"name":"Proceedings of the SOUTHERN BRAZILIAN JOURNAL OF CHEMISTRY 2021 INTERNATIONAL VIRTUAL CONFERENCE","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2022-03-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80590889","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-03-20DOI: 10.48141/sbjchem.21scon.17_abstract_bogo.pdf
Ricardo Bogo, R. P. Zeilmann
Machining is a process in constant evolution, the search for greater productivity, reliability, and quality of machined materials is fundamental for the constant evolution of the process. The condition of the tool edge is of great importance for the tool performance in machining, the edge of a tool after the manufacturing or re-sharpening process has defects such as: microcracks, irregularities, and an extremely sharp edge. The cutting edge treatment is used to remove these defects, which originate from the tool manufacturing and re-sharpening processes. In view of these listed points, this work aims to understand and evaluate the effects of cutting edge treatment by abrasive bristle brushes, taking into account the evolution of wear on the edge and tool life in the end milling process. The abrasive brushes covered in this work are technical brushes from the 3M brand, these brushes have different grain sizes and two different abrasives, silicon carbide (SiC) and aluminum oxide (Al2O3), their bristles are made of nylon of two different thicknesses. Based on the literature and to evaluate the performance of these brushes, points such as roughness and edge contour were addressed in this step, and as a result, the fine bristle brush with a SiC particle size of 1 micron had the best performance, these brushes produced a radius of 0.06 mm on the tool edges. The polishing process treated two tools, these tools went through the milling process in AISI P20 steel. As a result, the treated tools had a superior performance by 15,30% compared to untreated tools. In addition to increasing the useful life, the cutting edge treatment provided linear flank wear, delaying the presence of wear such as adhesion, microcracks, and microchips. The polishing edge treatment with abrasive bristle brushes proves to be an effective and reliable process for improving the performance of machining tools.
{"title":"INFLUENCE OF EDGE TREATMENT BY POLISHING WITH ABRASIVE BRUSH BRUSHES ON THE LIFE OF THE TOOL FOR THE MILLING PROCESS","authors":"Ricardo Bogo, R. P. Zeilmann","doi":"10.48141/sbjchem.21scon.17_abstract_bogo.pdf","DOIUrl":"https://doi.org/10.48141/sbjchem.21scon.17_abstract_bogo.pdf","url":null,"abstract":"Machining is a process in constant evolution, the search for greater productivity, reliability, and quality of machined materials is fundamental for the constant evolution of the process. The condition of the tool edge is of great importance for the tool performance in machining, the edge of a tool after the manufacturing or re-sharpening process has defects such as: microcracks, irregularities, and an extremely sharp edge. The cutting edge treatment is used to remove these defects, which originate from the tool manufacturing and re-sharpening processes. In view of these listed points, this work aims to understand and evaluate the effects of cutting edge treatment by abrasive bristle brushes, taking into account the evolution of wear on the edge and tool life in the end milling process. The abrasive brushes covered in this work are technical brushes from the 3M brand, these brushes have different grain sizes and two different abrasives, silicon carbide (SiC) and aluminum oxide (Al2O3), their bristles are made of nylon of two different thicknesses. Based on the literature and to evaluate the performance of these brushes, points such as roughness and edge contour were addressed in this step, and as a result, the fine bristle brush with a SiC particle size of 1 micron had the best performance, these brushes produced a radius of 0.06 mm on the tool edges. The polishing process treated two tools, these tools went through the milling process in AISI P20 steel. As a result, the treated tools had a superior performance by 15,30% compared to untreated tools. In addition to increasing the useful life, the cutting edge treatment provided linear flank wear, delaying the presence of wear such as adhesion, microcracks, and microchips. The polishing edge treatment with abrasive bristle brushes proves to be an effective and reliable process for improving the performance of machining tools.","PeriodicalId":20606,"journal":{"name":"Proceedings of the SOUTHERN BRAZILIAN JOURNAL OF CHEMISTRY 2021 INTERNATIONAL VIRTUAL CONFERENCE","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2022-03-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87931225","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-03-20DOI: 10.48141/sbjchem.21scon.22_abstract_avila.pdf
Letícia Meirelles Ávila, L. P. Gomes, G. M. Gomes, A. P. Abreu, E. C. R. Roier
Equinoculture is an activity of great importance in Brazil, moving millions of reais annually. For many years these animals were used only as a means of transport; however, currently, horses have assumed coverage in other areas of activity, such as leisure, sports, and even therapies, without escaping their main work functions in agricultural activities. Due to the significant requirement of the locomotor system, the affections of this system are quite common in this species. Therefore, these conditions must be diagnosed and treated early to completely restore the animal's functions. Intense exercises and very demanding tests subject these animals to limb injuries. They are fast-reacting animals and, sometimes, they can generate injuries due to the shock on surfaces and objects. These skin continuity solutions can act as a door of entry for infectious agents. Osteomyelitis is an infectious process that is accompanied by bone destruction, mainly caused by gram-positive bacteria. The prognosis of animals affected by this pathology is directly influenced by the speed of correct diagnosis and the beginning of appropriate treatment. It can put the sporting purpose of the animal and life at risk if it occurs late. The present report aims to describe the case of an adult female athlete, used for polo, presenting a lesion in the right forelimb and claudication grade 4/5. The diagnosis was obtained through clinical examination and radiographic study, finding radiographic changes compatible with osteomyelitis, and established treatment.
{"title":"OSTEOMYELITIS OF THE FIRST PHALANX IN A HORSE ATHLETE: CASE REPORT","authors":"Letícia Meirelles Ávila, L. P. Gomes, G. M. Gomes, A. P. Abreu, E. C. R. Roier","doi":"10.48141/sbjchem.21scon.22_abstract_avila.pdf","DOIUrl":"https://doi.org/10.48141/sbjchem.21scon.22_abstract_avila.pdf","url":null,"abstract":"Equinoculture is an activity of great importance in Brazil, moving millions of reais annually. For many years these animals were used only as a means of transport; however, currently, horses have assumed coverage in other areas of activity, such as leisure, sports, and even therapies, without escaping their main work functions in agricultural activities. Due to the significant requirement of the locomotor system, the affections of this system are quite common in this species. Therefore, these conditions must be diagnosed and treated early to completely restore the animal's functions. Intense exercises and very demanding tests subject these animals to limb injuries. They are fast-reacting animals and, sometimes, they can generate injuries due to the shock on surfaces and objects. These skin continuity solutions can act as a door of entry for infectious agents. Osteomyelitis is an infectious process that is accompanied by bone destruction, mainly caused by gram-positive bacteria. The prognosis of animals affected by this pathology is directly influenced by the speed of correct diagnosis and the beginning of appropriate treatment. It can put the sporting purpose of the animal and life at risk if it occurs late. The present report aims to describe the case of an adult female athlete, used for polo, presenting a lesion in the right forelimb and claudication grade 4/5. The diagnosis was obtained through clinical examination and radiographic study, finding radiographic changes compatible with osteomyelitis, and established treatment.","PeriodicalId":20606,"journal":{"name":"Proceedings of the SOUTHERN BRAZILIAN JOURNAL OF CHEMISTRY 2021 INTERNATIONAL VIRTUAL CONFERENCE","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2022-03-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84433387","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-03-20DOI: 10.48141/sbjchem.21scon.08_abstract_ferreyra.pdf
María Belén Piccoli, R. Vico, N. Ferreyra
Although carbon nanotubes have unique properties, one of the biggest drawbacks in practice is the difficulty in forming dispersions of individual nanotubes in a given solvent. Covalent functionalization of carbon nanotubes allows the incorporation of chemical groups at the nanotube surface that, according to its polarity, facilitates the dispersibility in different solvents. In this work, singled-wall carbon nanotubes were functionalized by spontaneous grafting with a diazonium salt obtained from the 4-aminobenzoic acid to obtain SWCNT-pB. The nanomaterial obtained was characterized by several methodologies that the covalent incorporation of the functional groups. SWCNT-pB were dispersed in ethanol/water 50% V/V under ultrasonic treatment, and the exfoliation degree was evaluated by UV-Vis spectrophotometry. under optimal conditions, SWCNT-pB dispersion was stable for more than 45 days. Glassy carbon electrodes (GCE) modified with the nanomaterial show significant increases in their capacitive current and a faradaic process due to redox species confined on the surface of SWCNT-pB whose anodic peak currents depend linearly with the scan rate. The modified electrodes also show a catalytic response towards ascorbic acid (AA) and notorious increments in the oxidation and reduction currents of H2O2. The stability of the dispersions and the excellent electrochemical responses obtained make this nanomaterial very interesting for its application in electrochemical detection.
{"title":"ELECTROCHEMICAL CHARACTERIZATION OF GLASSY CARBON ELECTRODES MODIFIED WITH SWCNT FUNCTIONALIZED WITH DIAZONIUM SALT","authors":"María Belén Piccoli, R. Vico, N. Ferreyra","doi":"10.48141/sbjchem.21scon.08_abstract_ferreyra.pdf","DOIUrl":"https://doi.org/10.48141/sbjchem.21scon.08_abstract_ferreyra.pdf","url":null,"abstract":"Although carbon nanotubes have unique properties, one of the biggest drawbacks in practice is the difficulty in forming dispersions of individual nanotubes in a given solvent. Covalent functionalization of carbon nanotubes allows the incorporation of chemical groups at the nanotube surface that, according to its polarity, facilitates the dispersibility in different solvents. In this work, singled-wall carbon nanotubes were functionalized by spontaneous grafting with a diazonium salt obtained from the 4-aminobenzoic acid to obtain SWCNT-pB. The nanomaterial obtained was characterized by several methodologies that the covalent incorporation of the functional groups. SWCNT-pB were dispersed in ethanol/water 50% V/V under ultrasonic treatment, and the exfoliation degree was evaluated by UV-Vis spectrophotometry. under optimal conditions, SWCNT-pB dispersion was stable for more than 45 days. Glassy carbon electrodes (GCE) modified with the nanomaterial show significant increases in their capacitive current and a faradaic process due to redox species confined on the surface of SWCNT-pB whose anodic peak currents depend linearly with the scan rate. The modified electrodes also show a catalytic response towards ascorbic acid (AA) and notorious increments in the oxidation and reduction currents of H2O2. The stability of the dispersions and the excellent electrochemical responses obtained make this nanomaterial very interesting for its application in electrochemical detection.","PeriodicalId":20606,"journal":{"name":"Proceedings of the SOUTHERN BRAZILIAN JOURNAL OF CHEMISTRY 2021 INTERNATIONAL VIRTUAL CONFERENCE","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2022-03-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85047239","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-03-20DOI: 10.48141/sbjchem.21scon.35_abstract_ceballos.pdf
Ceballos Noelia Marcela, G. Rimondino, F. Malanca, W. Peláez
Soybean residues were transformed through static pyrolysis carried out at temperatures between 250 °C and 350 °C. The gaseous fraction analysis showed that the gases emanated in the pyrolysis are mainly CO2 and CO. Furthermore, it was proved that this methodology constitutes a simple way to obtain useful carbons for the capture of pesticides present in an aqueous matrix. For example, the concentration of Chlorothalonil in a 7:3 water: acetonitrile solution decreases by 76-77 % through adsorption on the carbons obtained.
{"title":"PYROLYSIS OF SOYBEAN WASTE: A ROUTE TO ACTIVATED CARBON FOR FUNGICIDE CHLOROTHALONIL CAPTURE","authors":"Ceballos Noelia Marcela, G. Rimondino, F. Malanca, W. Peláez","doi":"10.48141/sbjchem.21scon.35_abstract_ceballos.pdf","DOIUrl":"https://doi.org/10.48141/sbjchem.21scon.35_abstract_ceballos.pdf","url":null,"abstract":"Soybean residues were transformed through static pyrolysis carried out at temperatures between 250 °C and 350 °C. The gaseous fraction analysis showed that the gases emanated in the pyrolysis are mainly CO2 and CO. Furthermore, it was proved that this methodology constitutes a simple way to obtain useful carbons for the capture of pesticides present in an aqueous matrix. For example, the concentration of Chlorothalonil in a 7:3 water: acetonitrile solution decreases by 76-77 % through adsorption on the carbons obtained.","PeriodicalId":20606,"journal":{"name":"Proceedings of the SOUTHERN BRAZILIAN JOURNAL OF CHEMISTRY 2021 INTERNATIONAL VIRTUAL CONFERENCE","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2022-03-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75981457","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
京公网安备 11010802042870号
京ICP备2023020795号-1
扫码关注我们
求助内容：
应助结果提醒方式：