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1.
Materials (Basel) ; 17(6)2024 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-38541430

RESUMO

This study examined the thermal dehydration characteristics of CaSO4∙2H2O in a constant-volume rotary vessel. The experiment used CaSO4∙2H2O particles obtained from the crushed waste gypsum board. The particle size ranged from 850 to 2000 µm, and the experiment was carried out at varying rotation speeds of 1, 10, and 35 rpm, with the vessel temperature heated to 180 °C. Temperature and pressure inside the vessel were measured simultaneously using the thermocouple and the pressure sensor. The XRPD measurement analyzed the transition of CaSO4∙2H2O after the heating of particles. The result showed that the temperature growth rate was similar for high rotation speeds of 10 and 35 rpm, while periodic temperature changes occurred at the low rotation speed of 1 rpm. A distinguishing flow pattern was observed at the low rotation speed, and the particles inside the vessel collapsed periodically downward. This particle behavior was related to the temperature distribution of the rotation speed of 1 rpm. Additionally, the pressure in the vessel increased rapidly at higher rotation speeds. This trend indicates the desorption of the crystal water of CaSO4∙2H2O due to the increasing temperature in the case of high rotation speed. Also, the XRPD measurement results showed the appearance of CaSO4∙0.5H2O under the higher rotation speed conditions, and the mass fraction of CaSO4∙0.5H2O increased with the rotation speed. Overall, the present study suggests that rotation speed plays a crucial role in determining the heat conduction and heat transfer of particles in a constant-volume rotary vessel.

2.
Materials (Basel) ; 15(6)2022 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-35329644

RESUMO

This study focused on the vibrating fluidized-bed-type powder feeder used in HVAF thermal spraying equipment. This feeder has been used in thermal spraying equipment and industrial applications. However, particulate materials' flow mechanism and stable transport characteristics have not been fully understood. This study experimentally investigated the fluidization characteristics, powder dispersion state, and powder transportation characteristics of Al2O3 particles during vertical vibration fluidization. The material used was Al2O3 particles of 2.9 µm and 3808 kg/m3, classified as the group C particles in the Geldart diagram. As experimental conditions, the fluidized air velocity to the bottom of the powder bed and the vibration intensity in the vertical direction changed. The critical fluidization air velocity was defined to evaluate the generating powder flow by vertical vibrating fluidization. As a result, good fluidization of the powder bed of Al2O3 was obtained by the vertical vibration, as well as an airflow that was higher than the critical fluidization air velocity. Regarding powder transportation characteristics, it was clarified that the fluidized air velocity at the bottom of the powder dispersion vessel and the pressure difference from the powder dispersion vessel to the transportation part significantly affect the mass flow rate.

3.
J Clin Pharmacol ; 55(11): 1286-92, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25969414

RESUMO

Two studies in healthy subjects assessed the absorption of edoxaban when delivered to specific locations within the gastrointestinal tract using Enterion capsules. In study 1 (single-dose, 4-way crossover), 8 participants received edoxaban 60 mg as immediate-release (IR) tablets (treatment A), as powder formulation delivered to the distal small bowel (treatment B) or ascending colon (treatment C), or as an aqueous suspension delivered to the ascending colon (treatment D). In study 2 (single-dose, 2-way crossover), 10 participants received edoxaban 30 mg as IR tablets (treatment E) or in granulate formulation with fumaric acid 50 mg, added to acidify the local gastrointestinal tract and enhance solubility, delivered to the ascending colon (treatment F). Peak and total exposure following targeted drug delivery to the distal gastrointestinal tract were significantly lower than with IR tablet delivery. In study 1, total exposure ratios of treatments B, C, and D compared with A were 14.9%, 7.9%, and 6.1%, respectively. In study 2, relative total exposure was 12.6% for treatment F despite the fumaric acid. Time to peak concentration was longer with higher variability for edoxaban delivered to the distal gastrointestinal tract compared with the IR tablet. These data indicate that edoxaban absorption occurs predominantly in the proximal small intestine.


Assuntos
Inibidores do Fator Xa/administração & dosagem , Inibidores do Fator Xa/farmacocinética , Absorção Gastrointestinal , Piridinas/administração & dosagem , Piridinas/farmacocinética , Tiazóis/administração & dosagem , Tiazóis/farmacocinética , Adolescente , Adulto , Idoso , Cápsulas , Colo/metabolismo , Estudos Cross-Over , Inibidores do Fator Xa/sangue , Fumaratos/administração & dosagem , Fumaratos/farmacocinética , Humanos , Intestino Delgado/metabolismo , Masculino , Pessoa de Meia-Idade , Piridinas/sangue , Comprimidos , Tiazóis/sangue , Adulto Jovem
4.
Thromb Res ; 135(4): 594-601, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25700621

RESUMO

INTRODUCTION: Since Vitamin K antagonists are associated with various limitations such as narrow therapeutic window, slow onset and offset of effect, and numerous interactions with food and drugs, new oral anticoagulants targeted to inhibit thrombin or factor Xa (FXa) have been developed. DY-807f is a highly selective, reversible and orally bioavailable FXa inhibitor. OBJECTIVES: This article describes a first-in-human study to evaluate the safety, tolerability, pharmacokinetics and pharmacodynamics of single ascending oral doses of the novel direct FXa inhibitor DY-807f in healthy males. METHODS: a placebo-controlled, single-blinded, randomized, single ascending dose study with 84 subjects (10, 30, 60, 120, 240, and 360 mg). Effects of food and formulation (tablet vs solution) on bioavailability of 60 mg were also assessed as a crossover design. RESULTS: DY-807f doses were safe and well-tolerated with no dose-dependent increase in adverse events up to 360 mg. Pharmacokinetics profiles were consistent across doses with rapid absorption, biphasic elimination, and terminal elimination half-life of 10.5 to 12.4 hours. Coagulation parameters (Activated Partial Thromboplastin Time (aPTT) and Prothrombin Time (PT)) were linearly correlated with plasma DY-807 (free base of DY-807f) concentrations (correlation coefficient: 0.786 for aPTT, 0.945 for PT). CONCLUSIONS: Single doses of DY-807f are safe and well-tolerated up to 360 mg with predictable pharmacokinetic and pharmacodynamic profiles.


Assuntos
Fibrilação Atrial/tratamento farmacológico , Inibidores do Fator Xa/farmacologia , Inibidores do Fator Xa/farmacocinética , Tromboembolia Venosa/tratamento farmacológico , Administração Oral , Adolescente , Adulto , Relação Dose-Resposta a Droga , Voluntários Saudáveis , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
5.
J Clin Pharmacol ; 50(7): 743-53, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20081065

RESUMO

This is a clinical safety, tolerability, pharmacokinetics (PK), and pharmacodynamics (PD) study of a single ascending dose (SAD) and a multiple ascending dose (MAD) of the oral direct factor Xa inhibitor edoxaban in healthy males. The placebo-controlled, single-blind, randomized, 2-part study consists of a SAD arm with 85 subjects (10, 30, 60, 90, 120, 150 mg) and a MAD arm with 36 subjects (90 mg daily, 60 mg twice daily, 120 mg daily). Effects of food and formulation (tablet vs solution) are assessed in a crossover substudy. In the SAD, doses are well tolerated up to 150 mg. Exposure is proportional to dose. PK profiles are consistent across dose with rapid absorption, biphasic elimination, and terminal elimination half-life of 5.8 to 10.7 hours. In the MAD, mean accumulation after daily dosing is 1.10 to 1.13 and consistent with elimination half-life of 8.75 to 10.4 hours. Intrasubject variability ranges from 12% to 17% for area under the curve. In general, plasma edoxaban concentrations are linearly correlated with coagulation parameters. Edoxaban is safe and well tolerated with no dose-dependent increases in adverse events. It is concluded that single and multiple doses of edoxaban are safe and well tolerated up to 150 mg with predictable PK and PD profiles.


Assuntos
Anticoagulantes/efeitos adversos , Anticoagulantes/farmacocinética , Inibidores do Fator Xa , Piridinas/efeitos adversos , Piridinas/farmacocinética , Tiazóis/efeitos adversos , Tiazóis/farmacocinética , Administração Oral , Adolescente , Adulto , Área Sob a Curva , Tempo de Sangramento , Relação Dose-Resposta a Droga , Fator Xa/metabolismo , Interações Alimento-Droga , Meia-Vida , Humanos , Coeficiente Internacional Normatizado , Masculino , Pessoa de Meia-Idade , Tempo de Tromboplastina Parcial , Tempo de Protrombina , Método Simples-Cego , Comprimidos , Adulto Jovem
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