Pub Date : 2004-03-30DOI: 10.11311/JSCTA1974.31.80
Y. Yoshihashi, E. Yonemochi, K. Terada
{"title":"Application of Isothermal Microcalorimetry for Stability Evaluation of Solid Dosage Form","authors":"Y. Yoshihashi, E. Yonemochi, K. Terada","doi":"10.11311/JSCTA1974.31.80","DOIUrl":"https://doi.org/10.11311/JSCTA1974.31.80","url":null,"abstract":"","PeriodicalId":19096,"journal":{"name":"Netsu Sokutei","volume":"19 1","pages":"80-86"},"PeriodicalIF":0.0,"publicationDate":"2004-03-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84445808","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 : 2004-03-30DOI: 10.11311/JSCTA1974.31.87
N. Murase
To understand the mechanism of ice crystallization during rewarming observed with a frozen crosslinked dextran gel of a certain density of crosslink, DSC, Raman scattering and X ray diffraction-DSC simultaneous measurements were conducted. It was found, as a result, that size of ice crystals as well as freezing behavior depend on the density of crosslink of the gels. By the study of two-dimensional X ray diffraction-DSC simultaneous measurements, formation of small ice crystals was indicated with the gel where ice crystallization during rewarming is observed. Presence of glassy water was also indicated in the frozen state of the gel by the measurement of Raman scattering. Then, it was clarified that ice crystallization in polymer gels is more or less obstructed by the polymer network, and by its change at the time of freezing. From these results together with the knowledge so far obtained, a conceivable mechanism of ice crystallization during rewarming was discussed.
{"title":"Ice Crystals and Glassy Water in Frozen Polymer Gels","authors":"N. Murase","doi":"10.11311/JSCTA1974.31.87","DOIUrl":"https://doi.org/10.11311/JSCTA1974.31.87","url":null,"abstract":"To understand the mechanism of ice crystallization during rewarming observed with a frozen crosslinked dextran gel of a certain density of crosslink, DSC, Raman scattering and X ray diffraction-DSC simultaneous measurements were conducted. It was found, as a result, that size of ice crystals as well as freezing behavior depend on the density of crosslink of the gels. By the study of two-dimensional X ray diffraction-DSC simultaneous measurements, formation of small ice crystals was indicated with the gel where ice crystallization during rewarming is observed. Presence of glassy water was also indicated in the frozen state of the gel by the measurement of Raman scattering. Then, it was clarified that ice crystallization in polymer gels is more or less obstructed by the polymer network, and by its change at the time of freezing. From these results together with the knowledge so far obtained, a conceivable mechanism of ice crystallization during rewarming was discussed.","PeriodicalId":19096,"journal":{"name":"Netsu Sokutei","volume":"13 1","pages":"87-92"},"PeriodicalIF":0.0,"publicationDate":"2004-03-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80256701","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 : 2004-03-30DOI: 10.11311/JSCTA1974.31.74
K. Kawakami
{"title":"Investigation of the structural Relaxation Process of Amorphous Formulation by Isothermal Microcalorimetry","authors":"K. Kawakami","doi":"10.11311/JSCTA1974.31.74","DOIUrl":"https://doi.org/10.11311/JSCTA1974.31.74","url":null,"abstract":"","PeriodicalId":19096,"journal":{"name":"Netsu Sokutei","volume":"85 1","pages":"74-79"},"PeriodicalIF":0.0,"publicationDate":"2004-03-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87107016","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 : 2004-03-30DOI: 10.11311/JSCTA1974.31.69
Y. Tozuka, Keiji. Yamamoto
This review describes the evaluation of molecular state of medicines by using differential scanning calorimetry (DSC). Thermal behavior of amorphous clarithromycin obtained by grinding and spray drying were evaluated. In DSC curves, both broad and sharp peaks for crystallization were observed in 30min ground sample, whereas spray-dried sample showed one broad peak for crystallization. In order to study the physicochemical stability of amorphous cefditoren pivoxil, glass transition accompanying enthalpy relaxation was evaluated for the ground and spray-dried samples by means of modulated-temperature DSC. Glass transition temperature (Tg) and relaxation enthalpy of the ground sample of cefditoren pivoxil were changed by storage for definite intervals at a temperature below Tg, while those of the spray-dried sample indicated an almost constant value by storage. These results suggest that the ground sample was less stable than the spray dried sample. The ground sample might be stabilized by storage below Tg. Thermal behavior of salicylamide in the mixtures with Folded Sheets Mesoporous Materials (FSM)-16 was investigated by DSC. Three kinds of molecular states of salicylamide, i.e., crystalline state, disordered crystalline state for which a broad endothermic peak was observed at a lower temperature, and amorphous state for which no peak on the DSC curves could be observed.
{"title":"Evaluation of Molecular State of Medicines by Differential Scanning Calorimetry","authors":"Y. Tozuka, Keiji. Yamamoto","doi":"10.11311/JSCTA1974.31.69","DOIUrl":"https://doi.org/10.11311/JSCTA1974.31.69","url":null,"abstract":"This review describes the evaluation of molecular state of medicines by using differential scanning calorimetry (DSC). Thermal behavior of amorphous clarithromycin obtained by grinding and spray drying were evaluated. In DSC curves, both broad and sharp peaks for crystallization were observed in 30min ground sample, whereas spray-dried sample showed one broad peak for crystallization. In order to study the physicochemical stability of amorphous cefditoren pivoxil, glass transition accompanying enthalpy relaxation was evaluated for the ground and spray-dried samples by means of modulated-temperature DSC. Glass transition temperature (Tg) and relaxation enthalpy of the ground sample of cefditoren pivoxil were changed by storage for definite intervals at a temperature below Tg, while those of the spray-dried sample indicated an almost constant value by storage. These results suggest that the ground sample was less stable than the spray dried sample. The ground sample might be stabilized by storage below Tg. Thermal behavior of salicylamide in the mixtures with Folded Sheets Mesoporous Materials (FSM)-16 was investigated by DSC. Three kinds of molecular states of salicylamide, i.e., crystalline state, disordered crystalline state for which a broad endothermic peak was observed at a lower temperature, and amorphous state for which no peak on the DSC curves could be observed.","PeriodicalId":19096,"journal":{"name":"Netsu Sokutei","volume":"108 1","pages":"69-73"},"PeriodicalIF":0.0,"publicationDate":"2004-03-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75718465","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 : 2004-03-30DOI: 10.11311/JSCTA1974.31.62
T. Kimura, T. Matsushita, Kenzi Suzuki, S. Takagi
{"title":"Excess Enthalpies of Some Nitrile Compounds + Methyl Methylthiomethyl Sulfoxide or + Dimethyl Sulfoxide at 298.15K","authors":"T. Kimura, T. Matsushita, Kenzi Suzuki, S. Takagi","doi":"10.11311/JSCTA1974.31.62","DOIUrl":"https://doi.org/10.11311/JSCTA1974.31.62","url":null,"abstract":"","PeriodicalId":19096,"journal":{"name":"Netsu Sokutei","volume":"56 1","pages":"62-68"},"PeriodicalIF":0.0,"publicationDate":"2004-03-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76020315","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 : 2004-01-25DOI: 10.11311/JSCTA1974.31.38
T. Fujii
{"title":"Accelerated Mixing on a Microfluidic Device","authors":"T. Fujii","doi":"10.11311/JSCTA1974.31.38","DOIUrl":"https://doi.org/10.11311/JSCTA1974.31.38","url":null,"abstract":"","PeriodicalId":19096,"journal":{"name":"Netsu Sokutei","volume":"51 1","pages":"38-38"},"PeriodicalIF":0.0,"publicationDate":"2004-01-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78279651","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}
{"title":"Water; Dynamics and Reactions","authors":"S. Saito, M. Matsumoto, I. Ohmine","doi":"10.11311/JSCTA1974.31.6","DOIUrl":"https://doi.org/10.11311/JSCTA1974.31.6","url":null,"abstract":"","PeriodicalId":19096,"journal":{"name":"Netsu Sokutei","volume":"174 1","pages":"6-13"},"PeriodicalIF":0.0,"publicationDate":"2004-01-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73357370","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 : 2004-01-25DOI: 10.11311/JSCTA1974.31.23
O. Mishima
{"title":"Polyamorphism in Water and the Second Critical Point Hypothesis","authors":"O. Mishima","doi":"10.11311/JSCTA1974.31.23","DOIUrl":"https://doi.org/10.11311/JSCTA1974.31.23","url":null,"abstract":"","PeriodicalId":19096,"journal":{"name":"Netsu Sokutei","volume":"4 1","pages":"23-28"},"PeriodicalIF":0.0,"publicationDate":"2004-01-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79371599","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 : 2004-01-25DOI: 10.11311/JSCTA1974.31.29
M. Sakata, E. Nishibori, M. Takata
The accurate charge density studies by the Maximum Entropy Method (MEM) utilizing X-ray diffraction is outlined with some examples. The basic concept of the method is stated in some details. In addition, some experimental charge densities are given to demonstrate the usefulness of the method, such as endohedral metallofullerenes, metal hydride and intermetallic compounds. In La2@C80 metallofullerene case, the extraordinary charge density distribution is revealed, that is two La atoms form pentagonal dodecahedron charge density due to the hopping motion inside fullerene cage. In MgH2 metal hydride case, charge density peaks of hydrogen atoms are clearly found in MEM charge density map, whereas no such charge density peaks are found in direct Fourier charge density map.
{"title":"Experimental Charge Density Distribution by the Maximum Entropy Method","authors":"M. Sakata, E. Nishibori, M. Takata","doi":"10.11311/JSCTA1974.31.29","DOIUrl":"https://doi.org/10.11311/JSCTA1974.31.29","url":null,"abstract":"The accurate charge density studies by the Maximum Entropy Method (MEM) utilizing X-ray diffraction is outlined with some examples. The basic concept of the method is stated in some details. In addition, some experimental charge densities are given to demonstrate the usefulness of the method, such as endohedral metallofullerenes, metal hydride and intermetallic compounds. In La2@C80 metallofullerene case, the extraordinary charge density distribution is revealed, that is two La atoms form pentagonal dodecahedron charge density due to the hopping motion inside fullerene cage. In MgH2 metal hydride case, charge density peaks of hydrogen atoms are clearly found in MEM charge density map, whereas no such charge density peaks are found in direct Fourier charge density map.","PeriodicalId":19096,"journal":{"name":"Netsu Sokutei","volume":"253 1","pages":"29-36"},"PeriodicalIF":0.0,"publicationDate":"2004-01-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73515351","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}