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Voltage reference based on LTZ1000 IC
Grohoľ, Stanislav ; Musil, Vladislav (referee) ; Hejátková, Edita (advisor)
The thesis deals with the issue of stability of voltage reference based on LTZ1000(A) integrated circuit. At the beginning are specified main parameters of voltage references in terms of stability. The work presents distribution references by architecture and by method of connection to the circuit. Work compares some references of Analog Devices and Linear Technology companies. In work is described voltage reference LTZ1000(A) and its circuits from datasheet. Listed are the main factor that influence the stability of reference, such as temperature, PCB design, Zener diode bias current, airflow and choice of circuit components. Given the description of a design module with the 7 V, 5 V and 10 V output. Made was three samples of PCB. Listed are results from long-term drift and temperature drift measures.
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Precise voltage references
Budáč, Peter ; Ing. Miroslav Horáček, Ph.D., ÚPT AVČR Brno (referee) ; Zobač,, Martin (advisor)
The aim of this thesis is the realization of the workplace to measure long-term stability and temperature coefficient of precision voltage references. It analyses individual solutions precision voltage references and their important parameters for the stability of the reference voltage. It deals with the influence of thermoelectric voltages and methods how to minizme their effect on measurement error . In conclusion it proposes a solution of this measuring workplace, and evaluate the results measuring of long-term stability and temperature coefficient on selected precision voltage references.
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Study of an alternative binder based on the carbonation of ladle funace slag
Mikulová, Mária ; Koplík, Jan (referee) ; Másilko, Jiří (advisor)
This master’s thesis is focused on the investigation of the chemical processes during the carbonation of a ladle furnace slag (LFSU) and on the investigation of the long-term development of the composition and selected properties of carbonated compacts of LFSU. The main mineralogical phases of the LFSU, -dicalcium silicate (-C2S) and -dicalcium silicate (-C2S), were synthetised for the study. The carbonation reactivity of these phases was examined by perfusion calorimetry. A significantly higher reactivity with CO2 for -C2S was observed. The development of compressive strength, changes in weight and length, and changes in phase composition of carbonated compacts of LFSU in four different environments (distilled water, room temperature; 100% relative humidity, room temperature; 60% relative humidity, 25 °C; exterior) during one year after carbonation were studied. A tendency of compressive strength increase in the first six months after carbonation and a decrease in compressive strength after one year from carbonation was observed in all environments. The long-term increase in compressive strength was mainly caused by hydration of -C2S and mayenite. The decrease in compressive strength after one year could have been caused by hydration of MgO to Mg(OH)2. This, however, was not clearly proved.
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Analysis of Historical Pharmaceutical Preparations Containing Alkaloids, Sulphonamide, Derivatives of Barbituric Acid, and Derivative of Pyrazolone
Kudláček, Karel ; Nesměrák, Karel (advisor) ; Bosáková, Zuzana (referee)
Pharmaceutical preparations of quinine (injection solutions), sulfanilamide, aminophenazone, barbital (tablets), caffeine, phenobarbital (dragee), and theophylline (suppositories) about seventy years old were analyzed using RP-HPLC. Samples were quantified by HPLC-UV and UV-spectrophotometry. Products of degradation were identified using HPLC-UV and HPLC-MS. Conditions of separation were optimized. The samples of quinine injection solutions consist of 92% or 87% of declared quinine content. Quinotoxine has been identified as the product of quinine degradation. The quantification of theophylline in suppositories and caffeine in dragee did not show any degradation after more than 67 years from their manufacturing. Decrase of potent amount (decrase about 8-22 %) were found in drugs containing sulfanilamide, barbital, phenobarbital and aminophenazone. Products of degradation of these pharmaceuticals were not found.
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Analysis of the degradation products of the active substances in historical pharmaceutical relicts from 18th and 20th century.
Čambal, Peter ; Nesměrák, Karel (advisor) ; Kubíčková, Anna (referee)
Historical pharmaceutical preparations analyzed in this thesis were a senna extract more than 200 years old, an ointment "Naso-Merfen" 75 years old, and an ointment "Sulfathiazol" 42 years old. The active substances in the analyzed samples were sennosides A and B (senna extract), ephedrine and menthol (the ointment "Naso-Merfen"), and sulfathiazole (the ointment "Sulfathiazol"). The senna extract was analyzed by RP-HPLC and HPLC-MS. Separation conditions were optimized, especially for separation of the sennoside A and B enantiomers. The active substances were not detected in the sample. One degradation product and substances characteristic for senna were identified. Their presence in the historical and contemporary sample was compared. Detailed ESI− -MSn fragmentation mechanisms of sennoside A and B have been proposed. The sample of the ointment "Naso-Merfen" was analyzed by HILIC-UV, HPLC-MS, GC-MS, and AAS. Separation conditions were optimized. The active substances were quantified. Degradation products of the active substances were not detected in the sample. The sample of the ointment "Sulfathiazol" was analyzed by RP-HPLC and HPLC-MS. Separation conditions were optimized. The active substance was quantified. Degradation products of the active substance were not detected. The authenticity of...
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Analysis of Historical Pharmaceutical Preparations Containing Alkaloids, Sulphonamide, Derivatives of Barbituric Acid, and Derivative of Pyrazolone
Kudláček, Karel ; Nesměrák, Karel (advisor) ; Bosáková, Zuzana (referee)
Pharmaceutical preparations of quinine (injection solutions), sulfanilamide, aminophenazone, barbital (tablets), caffeine, phenobarbital (dragee), and theophylline (suppositories) about seventy years old were analyzed using RP-HPLC. Samples were quantified by HPLC-UV and UV-spectrophotometry. Products of degradation were identified using HPLC-UV and HPLC-MS. Conditions of separation were optimized. The samples of quinine injection solutions consist of 92% or 87% of declared quinine content. Quinotoxine has been identified as the product of quinine degradation. The quantification of theophylline in suppositories and caffeine in dragee did not show any degradation after more than 67 years from their manufacturing. Decrase of potent amount (decrase about 8-22 %) were found in drugs containing sulfanilamide, barbital, phenobarbital and aminophenazone. Products of degradation of these pharmaceuticals were not found.
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Precise voltage references
Budáč, Peter ; Ing. Miroslav Horáček, Ph.D., ÚPT AVČR Brno (referee) ; Zobač,, Martin (advisor)
The aim of this thesis is the realization of the workplace to measure long-term stability and temperature coefficient of precision voltage references. It analyses individual solutions precision voltage references and their important parameters for the stability of the reference voltage. It deals with the influence of thermoelectric voltages and methods how to minizme their effect on measurement error . In conclusion it proposes a solution of this measuring workplace, and evaluate the results measuring of long-term stability and temperature coefficient on selected precision voltage references.
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Voltage reference based on LTZ1000 IC
Grohoľ, Stanislav ; Musil, Vladislav (referee) ; Hejátková, Edita (advisor)
The thesis deals with the issue of stability of voltage reference based on LTZ1000(A) integrated circuit. At the beginning are specified main parameters of voltage references in terms of stability. The work presents distribution references by architecture and by method of connection to the circuit. Work compares some references of Analog Devices and Linear Technology companies. In work is described voltage reference LTZ1000(A) and its circuits from datasheet. Listed are the main factor that influence the stability of reference, such as temperature, PCB design, Zener diode bias current, airflow and choice of circuit components. Given the description of a design module with the 7 V, 5 V and 10 V output. Made was three samples of PCB. Listed are results from long-term drift and temperature drift measures.
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