Pub Date : 1974-01-01DOI: 10.2109/JCERSJ1950.82.950_532
K. Hayashi, Tomozo Nishikawa, Isao Uei
The hot wire method has been used to measure thermal conductivity of massive solid materials. In order to find out a suitable way to measure thermal conductivity of granular solid materials, Ks, by hot wire method, the authors have examined the thermal conductivity measurement about the system of dispersed granular solid materials into a solid dispersion medium like silicon rubber. However, there were some limitations in the method that silicon rubber didn't work well at higher temperatures than 300°C and the rubber penetrated into the pore of granular solid materials in some cases. In this research, the authors tried to use some fluids to be applicable at higher temperatures and not to react with granular solid materials, and developed a method to be able to calculate Ks from gross thermal conductivity of granular solid-fluid mixture, K, and that of Kf.For the calculation of Ks from K and Kf, de Vries'equation was reasonably applied to both spherical and irregular-shaped particles. The shape factors Gi included in de Vries'equation were found to vary with the surface area of the granular solid materials in the case of spherical particles, but was almost constant in the irregular shaped particles.They wereG1=G2=5.34×10-4S+0.0374 G3=-1.07×10-3S+0.925} for spherical particle, G1=G2=0.05, G3=0.90 for irregular shaped particle, where S is surface area (cm2/cm3)The reliability of the results obtained by the application of de Vries' equation increased with the use of fluid having higher thermal conductivity. For example, when helium gas with thermal conductivity of 3.65×10-4cal/cm⋅sec⋅°C was used, the error of the obtained values Ks of 3.25×10-3 and 1.4×10-2cal/cm⋅sec⋅°C were about 4% and 8%, respectively.In view of the fact that the error increased with increasing thermal conductivity of granular solid materials to be measured, this method can be applied to the solid materials having thermal conductivity of smaller than about 1.5×10-2cal/cm⋅sec⋅°C, if the error of ±10% is allowable.
热丝法已被用于测量块状固体材料的导热系数。为了寻找一种适合于用热丝法测量颗粒状固体材料Ks导热系数的方法,本文对颗粒状固体材料在硅橡胶等固体分散介质中的分散体系导热系数的测量进行了研究。然而,该方法存在一定的局限性,硅橡胶在300℃以上的高温下不能很好地工作,在某些情况下,橡胶会渗透到颗粒状固体材料的孔隙中。在本研究中,作者尝试使用一些适用于较高温度且不与颗粒状固体材料发生反应的流体,并开发了一种能够通过颗粒状固体-流体混合物的总导热系数K和Kf计算Ks的方法。对于由K和Kf计算K, de Vries方程合理地适用于球形和不规则形状的粒子。de Vries方程中的形状因子Gi在球形颗粒的情况下随颗粒状固体材料表面积的变化而变化,而在不规则颗粒的情况下几乎是恒定的。对于球形颗粒为eg1 =G2=5.34×10-4S+0.0374 G3=-1.07×10-3S+0.925},对于不规则形状颗粒为G1=G2=0.05, G3=0.90,其中S为表面积(cm2/cm3)。使用导热系数较高的流体,应用de Vries方程所得结果的可靠性提高。以导热系数为3.65×10-4cal/cm·sec·°C的氦气为例,3.25×10-3和1.4×10-2cal/cm·sec·°C的k值误差分别为4%和8%左右。考虑到误差随待测颗粒状固体材料导热系数的增大而增大,在允许误差为±10%的情况下,该方法可应用于导热系数小于1.5×10-2cal/cm⋅sec⋅°C左右的固体材料。
{"title":"Studies on Thermal Conductivity Measurement of Granular Materials in System of Solid-Fluid Mixture","authors":"K. Hayashi, Tomozo Nishikawa, Isao Uei","doi":"10.2109/JCERSJ1950.82.950_532","DOIUrl":"https://doi.org/10.2109/JCERSJ1950.82.950_532","url":null,"abstract":"The hot wire method has been used to measure thermal conductivity of massive solid materials. In order to find out a suitable way to measure thermal conductivity of granular solid materials, Ks, by hot wire method, the authors have examined the thermal conductivity measurement about the system of dispersed granular solid materials into a solid dispersion medium like silicon rubber. However, there were some limitations in the method that silicon rubber didn't work well at higher temperatures than 300°C and the rubber penetrated into the pore of granular solid materials in some cases. In this research, the authors tried to use some fluids to be applicable at higher temperatures and not to react with granular solid materials, and developed a method to be able to calculate Ks from gross thermal conductivity of granular solid-fluid mixture, K, and that of Kf.For the calculation of Ks from K and Kf, de Vries'equation was reasonably applied to both spherical and irregular-shaped particles. The shape factors Gi included in de Vries'equation were found to vary with the surface area of the granular solid materials in the case of spherical particles, but was almost constant in the irregular shaped particles.They wereG1=G2=5.34×10-4S+0.0374 G3=-1.07×10-3S+0.925} for spherical particle, G1=G2=0.05, G3=0.90 for irregular shaped particle, where S is surface area (cm2/cm3)The reliability of the results obtained by the application of de Vries' equation increased with the use of fluid having higher thermal conductivity. For example, when helium gas with thermal conductivity of 3.65×10-4cal/cm⋅sec⋅°C was used, the error of the obtained values Ks of 3.25×10-3 and 1.4×10-2cal/cm⋅sec⋅°C were about 4% and 8%, respectively.In view of the fact that the error increased with increasing thermal conductivity of granular solid materials to be measured, this method can be applied to the solid materials having thermal conductivity of smaller than about 1.5×10-2cal/cm⋅sec⋅°C, if the error of ±10% is allowable.","PeriodicalId":17274,"journal":{"name":"Journal of the Ceramic Association, Japan","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1974-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73043079","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 : 1974-01-01DOI: 10.2109/JCERSJ1950.82.86
T. Ohsaka, A. Watanabe, Y. Hasegawa
Dielectric const ants of glasses in the system As-S-Se have been measured in the fre q uency range 30 to 6Hz at room tem pera ture. It is sho wn that die•@lectric cons tants of the glas•@s samp•@ les are al most ind•@ep ende•@ nt of freq uency over the meas uring frequency range. Dielectric constants of the glass system As40S60-xSex with 0_??_x_??_60 at fixed frequency (300kHz) increase linearly with Se content, while those of the glass system Asx (S, Se) 100-x with 10_??_x_??_45 increase nonlinearly with As content and show a maximum peak at about 40 atomic % As and then decrease with As content. [Received April 7, 1973]
{"title":"Dielectric Constants of Glasses in the System As-S-Se","authors":"T. Ohsaka, A. Watanabe, Y. Hasegawa","doi":"10.2109/JCERSJ1950.82.86","DOIUrl":"https://doi.org/10.2109/JCERSJ1950.82.86","url":null,"abstract":"Dielectric const ants of glasses in the system As-S-Se have been measured in the fre q uency range 30 to 6Hz at room tem pera ture. It is sho wn that die•@lectric cons tants of the glas•@s samp•@ les are al most ind•@ep ende•@ nt of freq uency over the meas uring frequency range. Dielectric constants of the glass system As40S60-xSex with 0_??_x_??_60 at fixed frequency (300kHz) increase linearly with Se content, while those of the glass system Asx (S, Se) 100-x with 10_??_x_??_45 increase nonlinearly with As content and show a maximum peak at about 40 atomic % As and then decrease with As content. [Received April 7, 1973]","PeriodicalId":17274,"journal":{"name":"Journal of the Ceramic Association, Japan","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1974-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85306169","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 : 1973-12-01DOI: 10.2109/JCERSJ1950.81.940_524
Katsuaki Takahashi, T. Yoshio
The heat contents of the alkali silicate glasses and crystals have been measured from 25°C to melting temperature with a continuous high-temperature calorimeter.The entropy in the above temperature range is determined for the glasses and crystals of the composition R2O⋅2SiO2 (R=Li, Na, K). The free-energy change is calculated for the reaction of forming the glasses from the crystals. The free-energy values thus obtained are compared with those calculated from two approximate equations, ΔG=ΔT⋅ΔHf/Tm and ΔG=(ΔT⋅ΔHf/Tm)⋅(T/Tm). This comparison indicates that the free-energy values from these equations are inapplicable to the discussion on the kinetic process except for the case in the narrow temperature range near the melting point.The relation between the heat capacity per mole of SiO2 and composition expressed by the mole ratio R2O/SiO2 at 300° and 600°C is also investigated. In the system Na2O-SiO2 crystals, the heat capacity increases linearly with Na2O/SiO2 ratio. The slope of this straight line and the intersection at zero Na2O composition approximately correspond to the heat capacity of crystalline Na2O and that of crystalline SiO2, respectively. From this result, it can be assumed that the additivity approximately holds for the heat capacity of Na2O-SiO2 crystals.For Na2O-SiO2 and K2O-SiO2 glasses and supercooled liquids, the composition dependence of heat capacity shows an inflection at the composition of R2O/SiO2=0.5. These results are discussed from the view point of structure of glass and liquid.
{"title":"Thermodynamic Quantities of Alkali Silicates in the Temperature Range from 25°C to Melting Point","authors":"Katsuaki Takahashi, T. Yoshio","doi":"10.2109/JCERSJ1950.81.940_524","DOIUrl":"https://doi.org/10.2109/JCERSJ1950.81.940_524","url":null,"abstract":"The heat contents of the alkali silicate glasses and crystals have been measured from 25°C to melting temperature with a continuous high-temperature calorimeter.The entropy in the above temperature range is determined for the glasses and crystals of the composition R2O⋅2SiO2 (R=Li, Na, K). The free-energy change is calculated for the reaction of forming the glasses from the crystals. The free-energy values thus obtained are compared with those calculated from two approximate equations, ΔG=ΔT⋅ΔHf/Tm and ΔG=(ΔT⋅ΔHf/Tm)⋅(T/Tm). This comparison indicates that the free-energy values from these equations are inapplicable to the discussion on the kinetic process except for the case in the narrow temperature range near the melting point.The relation between the heat capacity per mole of SiO2 and composition expressed by the mole ratio R2O/SiO2 at 300° and 600°C is also investigated. In the system Na2O-SiO2 crystals, the heat capacity increases linearly with Na2O/SiO2 ratio. The slope of this straight line and the intersection at zero Na2O composition approximately correspond to the heat capacity of crystalline Na2O and that of crystalline SiO2, respectively. From this result, it can be assumed that the additivity approximately holds for the heat capacity of Na2O-SiO2 crystals.For Na2O-SiO2 and K2O-SiO2 glasses and supercooled liquids, the composition dependence of heat capacity shows an inflection at the composition of R2O/SiO2=0.5. These results are discussed from the view point of structure of glass and liquid.","PeriodicalId":17274,"journal":{"name":"Journal of the Ceramic Association, Japan","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1973-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"72879214","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 : 1973-11-01DOI: 10.2109/JCERSJ1950.81.939_449
稔 田中, 卓 隅田
The thermal fracture of roofing tiles during cooling in tunnel kiln was studied by means of the photothermoelastic technique.The models of roofing tiles were made of epoxy resin plates. The isochromatic photographs of the fringe patterns showed the stress concentrations in the parts of notches and nail holes.For the purpose of decrease of stress concentration, some suggestions regarding the shape of notch and the position of nail hole were obtained. So as to avoid the thermal fracture, wide space setting of roofing tiles on the kiln-car is more effective than modification of cooling schedules.The temperature differences causing failure for the monotonous plate were theoretically estimated at from 160° to 170°C.
{"title":"トンネル窯焼成における粘土瓦の「冷め割れ」についての熱光弾性的研究","authors":"稔 田中, 卓 隅田","doi":"10.2109/JCERSJ1950.81.939_449","DOIUrl":"https://doi.org/10.2109/JCERSJ1950.81.939_449","url":null,"abstract":"The thermal fracture of roofing tiles during cooling in tunnel kiln was studied by means of the photothermoelastic technique.The models of roofing tiles were made of epoxy resin plates. The isochromatic photographs of the fringe patterns showed the stress concentrations in the parts of notches and nail holes.For the purpose of decrease of stress concentration, some suggestions regarding the shape of notch and the position of nail hole were obtained. So as to avoid the thermal fracture, wide space setting of roofing tiles on the kiln-car is more effective than modification of cooling schedules.The temperature differences causing failure for the monotonous plate were theoretically estimated at from 160° to 170°C.","PeriodicalId":17274,"journal":{"name":"Journal of the Ceramic Association, Japan","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1973-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90881686","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 : 1973-07-01DOI: 10.2109/JCERSJ1950.81.935_281
哲郎 吉田, 有次 岡田, 碩 平島
To elucidate the redox equilibrium of high concentration transition metal ions in a highly viscous oxide melts with gas phase, the effect of iron concentration on the redox equilibriums in the oxide melts of FeO-Fe2O3-RP2O6 system (R=Mg, Ca, Ba) at 1200°C with CO2 atmosphere, which oxygen partial pressure is about 10-3.6 atm, was studied in this report.The [Fe2+]/[Fe3+] ratios decreased at low iron oxide concentration and then increased after reaching their minimum values, as iron oxide concentration increased. These ratios also decreased at low iron oxide level and increased at high iron oxide level, as R was exchanged by Mg, Ca, Ba. The minimum values of [Fe2+]/[Fe3+] ratios shifted to the low iron oxide concentration by these exchange.It is discussed from these experimental results that the reaction between free ferrous ion and ferric oxiacid ion such asFe2++1/4 O2+(x-1/2)O2-=FeOx(2x-3)-contributes mainly to the redox equilibrium at the low iron oxide concentration, and that the reaction between oxiacid ions of ferrous and ferric ions such asFeOy(2y-2)-+1/4 O2=FeOx(2x-3)-+{1/2-(x-y)}O2-contributes mainly at the high iron oxide concentration.The relation between [Fe2+]/[Fe3+] and [O2-], oxygen ion concentration, given by the combination of the above two redox reactions, agrees with the experimental results about the relation between iron oxide concentration and [Fe2+]/[Fe3+] ratios in various melts, if the oxygen ion concentration increases with the increase of iron oxide concentration.The increase of oxygen ion concentration was recognized from the infra-red spectrums of glasses, obtained by quenching the melts in the redox equilibrium. Comparing the I. R. spectrums of FeO-Fe2O3-RP2O6 glasses with RP2O6 glasses, it was observed that the increase of iron oxide concentration corresponded to the exchanging R by Mg, Ca, Ba in RP2O6 glasses, the increase of basicity in the melts. This increase seemed to accompany with the change of the form (for example, chain length) of the phosphorus oxiacid ions in the melts. The formation of ferrous oxiacid ion in the melt was found to be possible from the shift of absorption peak by ferrous ion in the optical absorption spectrum in the above glass.Discussion about activities of various ions was not successful in this paper.
为了阐明高浓度过渡金属离子在高粘性气相氧化物熔体中的氧化还原平衡,本文研究了铁浓度对FeO-Fe2O3-RP2O6体系(R=Mg, Ca, Ba)在1200℃、氧分压约为10-3.6 atm的CO2气氛下氧化还原平衡的影响。[Fe2+]/[Fe3+]比值在低氧化铁浓度下下降,随着氧化铁浓度的增加达到最小值后上升。由于R被Mg、Ca、Ba交换,这些比值在低氧化铁水平下减小,在高氧化铁水平下增大。通过这种交换,[Fe2+]/[Fe3+]比值的最小值向低氧化铁浓度转移。从这些实验结果可以看出,在低氧化铁浓度下,自由亚铁离子与氧化铁离子(fe2 ++1/4 O2+(x-1/2)O2-=FeOx(2x-3))的反应主要起氧化还原平衡的作用,而在高氧化铁浓度下,铁离子与氧化铁离子(feoy (2y-2)-+1/4 O2=FeOx(2x-3)-+{1/2-(x-y)}O2的反应主要起氧化还原平衡的作用。结合上述两种氧化还原反应得到的[Fe2+]/[Fe3+]与[O2-]氧离子浓度的关系,与各熔体中氧化铁浓度与[Fe2+]/[Fe3+]比值关系的实验结果一致,即氧离子浓度随氧化铁浓度的增加而增加。通过在氧化还原平衡中淬火熔体得到的玻璃红外光谱,可以识别出氧离子浓度的增加。对比FeO-Fe2O3-RP2O6玻璃与RP2O6玻璃的红外光谱,发现氧化铁浓度的增加对应于RP2O6玻璃中Mg、Ca、Ba与R的交换,熔体碱度的增加。这种增加似乎伴随着熔体中磷氧化离子形式(例如,链长)的变化。从上述玻璃的光学吸收光谱中亚铁离子对吸收峰的移位发现熔体中氧化亚铁离子的形成是可能的。本文对各种离子的活性讨论不成功。
{"title":"FeO-Fe2O3-RP2O6 (R=Mg, Ca, Ba) 系ガラス熔融体と気相との酸化還元平衡に及ぼす酸化鉄濃度の影響","authors":"哲郎 吉田, 有次 岡田, 碩 平島","doi":"10.2109/JCERSJ1950.81.935_281","DOIUrl":"https://doi.org/10.2109/JCERSJ1950.81.935_281","url":null,"abstract":"To elucidate the redox equilibrium of high concentration transition metal ions in a highly viscous oxide melts with gas phase, the effect of iron concentration on the redox equilibriums in the oxide melts of FeO-Fe2O3-RP2O6 system (R=Mg, Ca, Ba) at 1200°C with CO2 atmosphere, which oxygen partial pressure is about 10-3.6 atm, was studied in this report.The [Fe2+]/[Fe3+] ratios decreased at low iron oxide concentration and then increased after reaching their minimum values, as iron oxide concentration increased. These ratios also decreased at low iron oxide level and increased at high iron oxide level, as R was exchanged by Mg, Ca, Ba. The minimum values of [Fe2+]/[Fe3+] ratios shifted to the low iron oxide concentration by these exchange.It is discussed from these experimental results that the reaction between free ferrous ion and ferric oxiacid ion such asFe2++1/4 O2+(x-1/2)O2-=FeOx(2x-3)-contributes mainly to the redox equilibrium at the low iron oxide concentration, and that the reaction between oxiacid ions of ferrous and ferric ions such asFeOy(2y-2)-+1/4 O2=FeOx(2x-3)-+{1/2-(x-y)}O2-contributes mainly at the high iron oxide concentration.The relation between [Fe2+]/[Fe3+] and [O2-], oxygen ion concentration, given by the combination of the above two redox reactions, agrees with the experimental results about the relation between iron oxide concentration and [Fe2+]/[Fe3+] ratios in various melts, if the oxygen ion concentration increases with the increase of iron oxide concentration.The increase of oxygen ion concentration was recognized from the infra-red spectrums of glasses, obtained by quenching the melts in the redox equilibrium. Comparing the I. R. spectrums of FeO-Fe2O3-RP2O6 glasses with RP2O6 glasses, it was observed that the increase of iron oxide concentration corresponded to the exchanging R by Mg, Ca, Ba in RP2O6 glasses, the increase of basicity in the melts. This increase seemed to accompany with the change of the form (for example, chain length) of the phosphorus oxiacid ions in the melts. The formation of ferrous oxiacid ion in the melt was found to be possible from the shift of absorption peak by ferrous ion in the optical absorption spectrum in the above glass.Discussion about activities of various ions was not successful in this paper.","PeriodicalId":17274,"journal":{"name":"Journal of the Ceramic Association, Japan","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1973-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88396233","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}
Packing behavior of the dry ramming mixes by method with stick penetration were in good agreement with calculations of author's previous report. Also, attempts at removal tendency of intermediate component were not so effective for obtaining a closer packing.It was shown that the q value of closest packing (=qρm) might shift to a lower value when the stick penetration times becames larger, and the qρm could be expressed as hyperbolic function of stick penetration times.Another intensified packing experiment of the dry mixes was shown that the qρm was inversely proportioned to the maximum particle-size, and that a closer packing was obtained as the particle were more spherical in shape.In packing experiment of the wet ramming mixes, the behavior by light ramming was similar to that of dry mixes, however, the packing intensity dependence and the maximum particle-size dependence on the qρm was not so much as that of dry mixes, and the shift of the qρm was lower than that of dry mixes.A different tendency about packing behavior by heavy ramming and press moulding of wet mixes was observed, that the qρm might shift to a higher value as the intensity of packing operation got higher, probably as a result of the crushing and defacement of grains.From these results, it might be concluded that the factors of the degree of packing for magnesia ramming mixes was moisture and binder, particle-shape, mechanical properties of magnesia clinker grain, maximum particle-size or extension of distribution, grading of particle-size, and intensity of packing operation.
{"title":"Packing of Magnesia Monolithic Refractories","authors":"Jun-ichi Kawamura, Hisaharu Hayami, Kisaburo Ariyoshi, Eiji Hosoi","doi":"10.2109/JCERSJ1950.81.935_263","DOIUrl":"https://doi.org/10.2109/JCERSJ1950.81.935_263","url":null,"abstract":"Packing behavior of the dry ramming mixes by method with stick penetration were in good agreement with calculations of author's previous report. Also, attempts at removal tendency of intermediate component were not so effective for obtaining a closer packing.It was shown that the q value of closest packing (=qρm) might shift to a lower value when the stick penetration times becames larger, and the qρm could be expressed as hyperbolic function of stick penetration times.Another intensified packing experiment of the dry mixes was shown that the qρm was inversely proportioned to the maximum particle-size, and that a closer packing was obtained as the particle were more spherical in shape.In packing experiment of the wet ramming mixes, the behavior by light ramming was similar to that of dry mixes, however, the packing intensity dependence and the maximum particle-size dependence on the qρm was not so much as that of dry mixes, and the shift of the qρm was lower than that of dry mixes.A different tendency about packing behavior by heavy ramming and press moulding of wet mixes was observed, that the qρm might shift to a higher value as the intensity of packing operation got higher, probably as a result of the crushing and defacement of grains.From these results, it might be concluded that the factors of the degree of packing for magnesia ramming mixes was moisture and binder, particle-shape, mechanical properties of magnesia clinker grain, maximum particle-size or extension of distribution, grading of particle-size, and intensity of packing operation.","PeriodicalId":17274,"journal":{"name":"Journal of the Ceramic Association, Japan","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1973-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77608930","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 : 1973-01-01DOI: 10.2109/JCERSJ1950.81.937_369
Minoru Tanaka, S. Sumita
Thermal properties and thermal fracture on the typical two kinds of clays of the roofing tile bodies i.e. chloritic "Awaji" roofing tile clay body and kaolinitic "Akashi" roofing tile clay body were studied at temperatures of 300•‹ to 700•Ž. Thermal properties observed were as follows: exoand endothermal phenomena on heating, heating weight loss, thermal expansion, bulk density, specific heat, thermal diffusivity, thermal conductivity, modulus of rupture and elasticity, and heat transfer coefficient. They were characteristic of dehydration of the clay minerals and quartz transformation. Assuming that a roofing tile body was a infinite slab of 1.6cm thickness, maximum safe heating or cooling rate "ƒÓmax" on the uniform heating or cooling and temperature difference causing fracture "ƒ¢Tf" were calculated from the following equations.
{"title":"Thermal Properties and Thermal Fracture on Clay Bodies of Roofing Tiles during Firing","authors":"Minoru Tanaka, S. Sumita","doi":"10.2109/JCERSJ1950.81.937_369","DOIUrl":"https://doi.org/10.2109/JCERSJ1950.81.937_369","url":null,"abstract":"Thermal properties and thermal fracture on the typical two kinds of clays of the roofing tile bodies i.e. chloritic \"Awaji\" roofing tile clay body and kaolinitic \"Akashi\" roofing tile clay body were studied at temperatures of 300•‹ to 700•Ž. Thermal properties observed were as follows: exoand endothermal phenomena on heating, heating weight loss, thermal expansion, bulk density, specific heat, thermal diffusivity, thermal conductivity, modulus of rupture and elasticity, and heat transfer coefficient. They were characteristic of dehydration of the clay minerals and quartz transformation. Assuming that a roofing tile body was a infinite slab of 1.6cm thickness, maximum safe heating or cooling rate \"ƒÓmax\" on the uniform heating or cooling and temperature difference causing fracture \"ƒ¢Tf\" were calculated from the following equations.","PeriodicalId":17274,"journal":{"name":"Journal of the Ceramic Association, Japan","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1973-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75071285","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 : 1972-01-01DOI: 10.2109/JCERSJ1950.80.924_337
A. Yamaguchi, E. Kato
Anhydrous magnesium sulfate exists in two monotropic forms and its transition point 595°±5°C. The data of the lowtemperature form correspond to that reported by P. J. Rentzeperis et al.The high-temperature form is orthorhombic and its lattice constants 4.750, 8.589 and 6.703A.
无水硫酸镁以两种单性形式存在,其转变点为595°±5°C。低温态的数据与P. J. Rentzeperis等人的报告一致,高温态为正交型,晶格常数分别为4.750、8.589和6.703A。
{"title":"Heat Effects of Anhydrous Magnesium Sulfate","authors":"A. Yamaguchi, E. Kato","doi":"10.2109/JCERSJ1950.80.924_337","DOIUrl":"https://doi.org/10.2109/JCERSJ1950.80.924_337","url":null,"abstract":"Anhydrous magnesium sulfate exists in two monotropic forms and its transition point 595°±5°C. The data of the lowtemperature form correspond to that reported by P. J. Rentzeperis et al.The high-temperature form is orthorhombic and its lattice constants 4.750, 8.589 and 6.703A.","PeriodicalId":17274,"journal":{"name":"Journal of the Ceramic Association, Japan","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1972-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83130268","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 : 1972-01-01DOI: 10.2109/JCERSJ1950.80.37
W. Komatsu, Y. Moriyoshi
The effect of oxygen pressure on sintering of zinc oxide has been investigated by measuring isothermal shrinkage of compacts at 750° and 850°C. The sinterability was proportional to Po2-1/5.4 at 750°C in oxygen atomsphere (Po2>2.5×10-2torr) and to Po2-1/5.4 at 850°C in Po2>3×10-3torr. The result indicates that the sintering process is controlled by diffusional transfer of interstitial zinc ions. In the lower oxygen pressure, the sintering rate was independent of the pressure. This result was explained by the cooperation of two different mechanisms, i.e., diffusional transfer of interstitial zinc ions and lattice formation process between interstitial zinc and oxygen.
{"title":"The effect of oxygen pressure on sintering of zinc oxide","authors":"W. Komatsu, Y. Moriyoshi","doi":"10.2109/JCERSJ1950.80.37","DOIUrl":"https://doi.org/10.2109/JCERSJ1950.80.37","url":null,"abstract":"The effect of oxygen pressure on sintering of zinc oxide has been investigated by measuring isothermal shrinkage of compacts at 750° and 850°C. The sinterability was proportional to Po2-1/5.4 at 750°C in oxygen atomsphere (Po2>2.5×10-2torr) and to Po2-1/5.4 at 850°C in Po2>3×10-3torr. The result indicates that the sintering process is controlled by diffusional transfer of interstitial zinc ions. In the lower oxygen pressure, the sintering rate was independent of the pressure. This result was explained by the cooperation of two different mechanisms, i.e., diffusional transfer of interstitial zinc ions and lattice formation process between interstitial zinc and oxygen.","PeriodicalId":17274,"journal":{"name":"Journal of the Ceramic Association, Japan","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1972-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73298663","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 : 1971-01-01DOI: 10.2109/JCERSJ1950.79.911_225
A. Naruse, Y. Abe, A. Takami
The composition dependence of some physical properties of Cabal and Babal glasses is discussed for the purpose of elucidating the role of aluminum ion in the structure of alkaline earth aluminoborate glasses. To interpret the experimental results on the basis of the glass structure, three rules are assumed about interlinking relation among AlO4 tetrahedron, BO4 tetrahedron and BO3 triangle as follows. (Rule 1) In the structure of alkaline earth aluminoborate glass, when each content of MO and B2O3 in the glass exceeds a definite value, preferential interlinking between AlO4 and BO4 groups is made into the formation of a tetrahedron couple comprising those two kinds of tetrahedral group. (Rule 2) The interlinked tetrahedron couple is impossible to exist only by itself, but is forced to link to BO3 triangles at its six corners in any case. Hence, the formation of AlB3O7
{"title":"Role of Aluminum Ion in the Structure of Alkaline Earth Aluminoborate Glasses","authors":"A. Naruse, Y. Abe, A. Takami","doi":"10.2109/JCERSJ1950.79.911_225","DOIUrl":"https://doi.org/10.2109/JCERSJ1950.79.911_225","url":null,"abstract":"The composition dependence of some physical properties of Cabal and Babal glasses is discussed for the purpose of elucidating the role of aluminum ion in the structure of alkaline earth aluminoborate glasses. To interpret the experimental results on the basis of the glass structure, three rules are assumed about interlinking relation among AlO4 tetrahedron, BO4 tetrahedron and BO3 triangle as follows. (Rule 1) In the structure of alkaline earth aluminoborate glass, when each content of MO and B2O3 in the glass exceeds a definite value, preferential interlinking between AlO4 and BO4 groups is made into the formation of a tetrahedron couple comprising those two kinds of tetrahedral group. (Rule 2) The interlinked tetrahedron couple is impossible to exist only by itself, but is forced to link to BO3 triangles at its six corners in any case. Hence, the formation of AlB3O7","PeriodicalId":17274,"journal":{"name":"Journal of the Ceramic Association, Japan","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1971-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83010622","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}