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Surface treatment methods applied to 3D printed samples and their analysis
Rygl, Michal ; Dobrocký, David (referee) ; Sedlák, Josef (advisor)
The presented paper deals with the issue of smoothing parts produced using FFF 3D printing technology. The aim of the paper was to compare technical surface treatment methods and economic side. Emphasis was placed especially on the degree of reduction of surface roughness while maintaining an acceptable level of process costs. Chemical smoothing, local CO2 laser melting, tumbling and surface treatment based on filler spraying were used to smooth the plastic prints. Prints made of ABS, PLA, PolySmooth and PolyCast were subjected to the smoothing process. Printing parameters were first determined for individual materials and test samples were produced on their basis. After determining the process parameters for individual surface treatment methods, the finished surfaces were measured with a profilometer. Based on the results, the chemical etching method was evaluated as the most effective surface smoothing method. Due to the etching of the surface layer of the sample made of PolySmooth material, the surface roughness parameter Sa was reduced in diameter compared to the reference sample. by 99,56 %. The least effective method was tumbling technology, which showed an average roughness reduction of 30,07 % in the case of ABS. However, the technology based on grinding parts with grinding stones had the lowest process costs for finishing the samples. Technical The economically best choice of all tested combinations was the technology of chemical etching of ABS polymer prints. The results and conclusions of the work will serve not only to select the finishing operation and material for specific applications of prints in practice, but also to expand the possibilities of using additively produced components.
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Advanced materials for FDM/FFF 3D print
Rygl, Michal ; Vespalec, Arnošt (referee) ; Koutecký, Tomáš (advisor)
The presented work deals with the issue of FDM / FFF 3D printing with a focus on materials with added carbon fiber. The aim of this work is to experimentally analyze the effect of carbon additive on printed parts using mechanical and thermomechanical tests. Testing of selected materials has shown that the effect of carbon additive varies according to the used base material. For example, carbon in PET-G has reduced impact strength by up to 64%. However, carbon filled CPE has demonstrated the ability to absorb impact energy up to by 28.5%. The different effect of carbon fiber was measured on the CPE material in a tensile test, where the yield strength was reduced during the stretching of the samples at room temperature, but the modulus of elasticity was increased. The absolutely positive effect of carbon was measured on all observed polymer filaments in the thermomechanical 3-point bending test, when the carbon versions of the materials achieved better results. The measured data brings an extension of the possibility of comparing the results with other types of materials suitable for 3D printing in the field of research. From a practical point of view the test results can be used for the actual choice of material when printing models has specific conditions of use. Another practical use of the analyzed data is the use of printable results of advanced materials for the creation of print profiles for other desktop 3D printers of the FDM/FFF type.
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Surface treatment methods applied to 3D printed samples and their analysis
Rygl, Michal ; Dobrocký, David (referee) ; Sedlák, Josef (advisor)
The presented paper deals with the issue of smoothing parts produced using FFF 3D printing technology. The aim of the paper was to compare technical surface treatment methods and economic side. Emphasis was placed especially on the degree of reduction of surface roughness while maintaining an acceptable level of process costs. Chemical smoothing, local CO2 laser melting, tumbling and surface treatment based on filler spraying were used to smooth the plastic prints. Prints made of ABS, PLA, PolySmooth and PolyCast were subjected to the smoothing process. Printing parameters were first determined for individual materials and test samples were produced on their basis. After determining the process parameters for individual surface treatment methods, the finished surfaces were measured with a profilometer. Based on the results, the chemical etching method was evaluated as the most effective surface smoothing method. Due to the etching of the surface layer of the sample made of PolySmooth material, the surface roughness parameter Sa was reduced in diameter compared to the reference sample. by 99,56 %. The least effective method was tumbling technology, which showed an average roughness reduction of 30,07 % in the case of ABS. However, the technology based on grinding parts with grinding stones had the lowest process costs for finishing the samples. Technical The economically best choice of all tested combinations was the technology of chemical etching of ABS polymer prints. The results and conclusions of the work will serve not only to select the finishing operation and material for specific applications of prints in practice, but also to expand the possibilities of using additively produced components.
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Various Surgical Techniques of Lesional vas Deferens Repair in Rat Experiments
Štichhauer, Radek ; Kaška, Milan (advisor) ; Rygl, Michal (referee) ; Plánka, Ladislav (referee)
Various surgical techniques for the repair of injured vas deferens in rat experiment Introduction: The herniotomy for inguinal hernia is one of the most frequent surgical procedures in paediatric surgery. The incidence of complication following primary inguinal herniotomy in neonates is not rare and repair of the injured vas deferens (VD) is not standardized. The aim of this experimental study was to assess the contusion of VD during the surgery with a surgical instrument and to perform and consequently analyze some possibilities of a simple repair method under the control of operating loupe. Methods: Seventy male rats were divided into seven subgroups according to the type of the vas deferens injury and its repair consequently: 1. Contusion, 2. cut-off and a simple one layer vasovasostomy sewn by absorbable sewing material, 3. cut-off and joining by an intraluminally lead fibre of absorbable sewing material knotted externally, 4. = 3. using non- absorbable sewing material, 5. = 2. combine with intraluminally situated absorbable sewing fibre fixed externally,6. = 5. combine with intraluminally situated non-absorbable sewing fibre fixed externally, 7. = 5. without external fixation. Fibres of non-absorbable sewing material were removed 3 weeks after the first operation. Operated or injured parts of...
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Prediction of intestinal damage in neonates with gastroschisis
Frýbová, Barbora ; Rygl, Michal (advisor) ; Pešl, Tomáš (referee) ; Straňák, Zbyněk (referee)
Prediction of intestinal damage in neonates with gastroschisis MUDr. Frýbová Barbora Objective: The aim of the study was to identify both prenatal ultrasonographic markers in fetuses and a biochemical marker in newborns with gastroschisis that predict postnatal outcome; to perform a new technique of defect closure by preformed silicone silo for gastroschisis and to evaluate long-term quality of life and somatic growth of patients with gastroschisis and compare them with the general population. Material and Methods: The analysis of 122 patients with gastroschisis operated on between 2004-2018 at the Department of Paediatric Surgery of University Hospital Motol in Prague was performed. In the retrospective-prospective study (97 patients) ultrasound findings at the 30th week of pregnancy and medical reports were statistically analyzed to identify independent prenatal ultrasonographic predictors of postnatal outcome. In the prospective study, new surgical technique of preformed silicone silo for gastroschisis to perform the stepwise defect reconstruction was used in four patients. In the prospective I-FABP study (53 patients), the urine was collected during the first 48 hours after surgery from neonates operated on for GS. Neonates with surgery that did not include gut mucosa served as controls for...
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Nursing care of a newborn with oesophageal atresia
Chlumová, Hana ; Sedlářová, Petra (advisor) ; Rygl, Michal (referee)
The bachelor thesis deals with diagnostic procedure, treatment and nursing process in a newborn diagnosed with esophageal atresia without fistula. The work consists of clinical part, in which anatomy of esophagus, prenatal evolution of esophagus, types of esophageal atresia, options of surgery, prediction and complications of this disease are briefly described and at the end there is a description of the course of hospitalization. Nursing part consists of a theoretical section describing the nursing process and the nursing model of Virginia Henderson. In the next part of work is the needs of the patient are assessed according to this model. Nursing diagnoses are described both for the period before surgery and immediately after the first operation. Due to the lenght of stay the long-term plan of nursing care is intertwined with information, instructions and guidance of the parents The work also contains a list of used drugs with their brief characteristics. In supplement scoring tables, X-ray documentaion, and information for the parents are presented.
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Advanced materials for FDM/FFF 3D print
Rygl, Michal ; Vespalec, Arnošt (referee) ; Koutecký, Tomáš (advisor)
The presented work deals with the issue of FDM / FFF 3D printing with a focus on materials with added carbon fiber. The aim of this work is to experimentally analyze the effect of carbon additive on printed parts using mechanical and thermomechanical tests. Testing of selected materials has shown that the effect of carbon additive varies according to the used base material. For example, carbon in PET-G has reduced impact strength by up to 64%. However, carbon filled CPE has demonstrated the ability to absorb impact energy up to by 28.5%. The different effect of carbon fiber was measured on the CPE material in a tensile test, where the yield strength was reduced during the stretching of the samples at room temperature, but the modulus of elasticity was increased. The absolutely positive effect of carbon was measured on all observed polymer filaments in the thermomechanical 3-point bending test, when the carbon versions of the materials achieved better results. The measured data brings an extension of the possibility of comparing the results with other types of materials suitable for 3D printing in the field of research. From a practical point of view the test results can be used for the actual choice of material when printing models has specific conditions of use. Another practical use of the analyzed data is the use of printable results of advanced materials for the creation of print profiles for other desktop 3D printers of the FDM/FFF type.
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Prediction of intestinal damage in neonates with gastroschisis
Frýbová, Barbora ; Rygl, Michal (advisor) ; Pešl, Tomáš (referee) ; Straňák, Zbyněk (referee)
Prediction of intestinal damage in neonates with gastroschisis MUDr. Frýbová Barbora Objective: The aim of the study was to identify both prenatal ultrasonographic markers in fetuses and a biochemical marker in newborns with gastroschisis that predict postnatal outcome; to perform a new technique of defect closure by preformed silicone silo for gastroschisis and to evaluate long-term quality of life and somatic growth of patients with gastroschisis and compare them with the general population. Material and Methods: The analysis of 122 patients with gastroschisis operated on between 2004-2018 at the Department of Paediatric Surgery of University Hospital Motol in Prague was performed. In the retrospective-prospective study (97 patients) ultrasound findings at the 30th week of pregnancy and medical reports were statistically analyzed to identify independent prenatal ultrasonographic predictors of postnatal outcome. In the prospective study, new surgical technique of preformed silicone silo for gastroschisis to perform the stepwise defect reconstruction was used in four patients. In the prospective I-FABP study (53 patients), the urine was collected during the first 48 hours after surgery from neonates operated on for GS. Neonates with surgery that did not include gut mucosa served as controls for...
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Various Surgical Techniques of Lesional vas Deferens Repair in Rat Experiments
Štichhauer, Radek ; Kaška, Milan (advisor) ; Rygl, Michal (referee) ; Plánka, Ladislav (referee)
Various surgical techniques for the repair of injured vas deferens in rat experiment Introduction: The herniotomy for inguinal hernia is one of the most frequent surgical procedures in paediatric surgery. The incidence of complication following primary inguinal herniotomy in neonates is not rare and repair of the injured vas deferens (VD) is not standardized. The aim of this experimental study was to assess the contusion of VD during the surgery with a surgical instrument and to perform and consequently analyze some possibilities of a simple repair method under the control of operating loupe. Methods: Seventy male rats were divided into seven subgroups according to the type of the vas deferens injury and its repair consequently: 1. Contusion, 2. cut-off and a simple one layer vasovasostomy sewn by absorbable sewing material, 3. cut-off and joining by an intraluminally lead fibre of absorbable sewing material knotted externally, 4. = 3. using non- absorbable sewing material, 5. = 2. combine with intraluminally situated absorbable sewing fibre fixed externally,6. = 5. combine with intraluminally situated non-absorbable sewing fibre fixed externally, 7. = 5. without external fixation. Fibres of non-absorbable sewing material were removed 3 weeks after the first operation. Operated or injured parts of...
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