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Akiyo Tanaka - One of the best experts on this subject based on the ideXlab platform.
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toxicity of Indium Arsenide gallium Arsenide and aluminium gallium Arsenide
Toxicology and Applied Pharmacology, 2004Co-Authors: Akiyo TanakaAbstract:Gallium Arsenide (GaAs), Indium Arsenide (InAs), and aluminium gallium Arsenide (AlGaAs) are semiconductor applications. Although the increased use of these materials has raised concerns about occupational exposure to them, there is little information regarding the adverse health effects to workers arising from exposure to these particles. However, available data indicate these semiconductor materials can be toxic in animals. Although acute and chronic toxicity of the lung, reproductive organs, and kidney are associated with exposure to these semiconductor materials, in particular, chronic toxicity should pay much attention owing to low solubility of these materials. Between InAs, GaAs, and AlGaAs, InAs was the most toxic material to the lung followed by GaAs and AlGaAs when given intratracheally. This was probably due to difference in the toxicity of the counter-element of arsenic in semiconductor materials, such as Indium, gallium, or aluminium, and not arsenic itself. It appeared that Indium, gallium, or aluminium was toxic when released from the particles, though the physical character of the particles also contributes to toxic effect. Although there is no evidence of the carcinogenicity of InAs or AlGaAs, GaAs and InP, which are semiconductor materials, showed the clear evidence of carcinogenic potential. It is necessary to pay much greater attention to the human exposure of semiconductor materials.
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Pulmonary squamous cyst induced by exposure to Indium Arsenide in hamsters.
Journal of occupational health, 2003Co-Authors: Akiyo Tanaka, Miyuki Hirata, Minoru OmuraAbstract:Indium Arsenide (InAs) belongs to the group of semiconductor materials comprising III-V compounds . With the increasing industrial use of InAs, the question as to whether or not occupational exposure to this material is a potential health hazard has been attracting attention. To date, there is no information regarding adverse health effects on workers arising from their exposure to InAs particles. In our previous study, we confirmed the development of proteinosis-like lesions or localized hyperplastic lesions in the lungs of hamsters which had been induced by exposure to InAs particles. In particular, alveolar or bronchiolar cell hyperplasia with squamous cell metaplasia, squamous cell hyperplasia or squamous cell metaplasia with keratinization were observed when 7.7 mg/kg of InAs was instilled intratracheally, twice a week for a total of 14 times. Accordingly, a further study was undertaken with only half the dose (4 mg/kg). As a result, neoplastic change was never evident. We therefore considered that it was necessary to use a dose in excess of 4 mg/kg of InAs per instillation in order to give rise to a neoplastic response. The aim of the present study was to confirm whether the localized hyperplastic lesions induced by the overloaded condition of InAs particles actually represented a neoplastic response, or not. In this study, 8 mg/kg of InAs was instilled and double the number of hamsters (n=16), compared with that (n=8) in the previous study, received the particles.
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Long Term Pulmonary Toxicity of Indium Arsenide and Indium Phosphide Instilled Intratracheally in Hamsters
Journal of Occupational Health, 2000Co-Authors: Koji Yamazaki, Akiyo Tanaka, Miyuki Hirata, Minoru Omura, Yuji Makita, Naohide Inoue, Kenji Sugio, Keizo SugimachiAbstract:Long Term Pulmonary Toxicity of Indium Arsenide and Indium Phosphide Instilled Intratracheally in Hamsters: Koji YAMAZAKI, et al. Department of Hygiene, Graduate School of Medical Sciences, Kyushu University—We examined the long-term toxicological effects of III-V semiconductor particles on laboratory animals. Eight-week-old male Syrian golden hamsters were given 4 mg/kg Indium Arsenide (InAs) or 3 mg/kg Indium phosphide (InP) particles, both containing 2.4 mg/kg as Indium, intratracheally twice a week for 8 weeks. Control hamsters were given only a vehicle, phosphate buffer solution. Over a 2-yr period, these animals were euthanized serially and the biological effects were determined. Weight gain was significantly suppressed in both InAs and InP groups, compared to the control group, with greater suppression in the InAs group. The serum Indium concentration in the InAs group was about twice as high as that in the InP group, in each period. Histopathologically, severe pulmonary inflammation and localized lesions with bronchioloalveolar cell hyperplasia were present in both InAs and InP groups from just after the last administration. The localized lesions gradually transformed to proteinosislike lesions with periodic acid Schiff reagent positive exudation after 16 wk. By means of immunostaining of proliferating cell nuclear antigen and argyrophilic proteins associated with nucleolar organizer regions staining, proliferative activities were evidenced in the localized lesions at each time and were noticeable in their early stage. K-ras, a known oncogene, was not mutated in association with these lesions. In conclusion, InAs and InP particles caused severe systemic toxicity and pulmonary localized hyperplastic lesions with proliferative activity were derived via the respiratory route. Neoplastic change was nil even in a 2-yr observation period.
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Changes in the testicular damage caused by Indium Arsenide and Indium phosphide in hamsters during two years after intratracheal instillations
Journal of Occupational Health, 2000Co-Authors: Minoru Omura, Akiyo Tanaka, Koji Yamazaki, Miyuki Hirata, Yuji Makita, Naohide InoueAbstract:Changes in the Testicular Damage Caused by Indium Arsenide and Indium Phosphide in Hamsters during Two Years after Intratracheal Instillations: Minoru OMURA, et al. Department of Hygiene, Graduate School of Medical Sciences, Kyushu University—Change in the testicular damage caused by Indium Arsenide (InAs) and Indium phosphide (InP) was examined during two yr after repetitive intratracheal instillations in hamsters. In this study, 4.0 mg/kg body weight/day of InAs or 3.0 mg/kg body weight/day of InP was instilled intratracheally twice weekly for eight wk. A single instillation dose of Indium was 2.4 mg/kg body weight in both groups. Testicular damage was evaluated 0, 8, 16, 40, 64 and 88 wk after the last instillation. Both InAs and InP were proved to be definite testicular toxicants. Both materials decreased reproductive organ weight and caudal sperm count, and caused severe histopathologic changes in the testes. InAs-induced testicular damage was always more serious than InP-induced testicular damage. The serum Indium concentration in the InAs group was always higher than that in the InP group, and Indium was probably a toxic element in both materials. In the histopathologic examination, vacuolization of seminiferous epithelium was frequently observed as an early histopathologic change and spermatogonia remained in general even in the seminiferous tubules with severe histopathologic changes in both groups. It is therefore estimated that Sertoli cells, not stem cell spermatogonia, were the target cells of these Indiumcontaining compound semiconductor materials. The threat of InAs and InP to male reproduction was proved in this study. We concluded that male reproductive disorders should not be overlooked when severe exposure to Indium-containing compound semiconductor materials is apparent in human subjects.
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testicular toxicity evaluation of arsenic containing binary compound semiconductors gallium Arsenide and Indium Arsenide in hamsters
Toxicology Letters, 1996Co-Authors: Minoru Omura, Akiyo Tanaka, Miyuki Hirata, Yuji Makita, Naohide Inoue, Mangen Zhao, Kaoru Gotoh, Noburu IshinishiAbstract:Abstract The testicular toxicities of gallium Arsenide (GaAs), Indium Arsenide (InAs) and arsenic trioxide (As 2O 3) were examined by repetitive intratracheal instillation using hamsters. GaAs (7.7 mg/kg) and As 2O 3 (1.3 mg/kg) were instilled twice a week a total of 16 times and InAs (7.7 mg/kg) was instilled a total of 14 times. GaAs caused testicular spermatid retention and epididymal sperm reduction, though the degrees were less severe than those in rats shown in our previous experiment. InAs and As2O3 did not show any testicular toxicities. Serum arsenic concentration in GaAs-treated hamsters was less than half of that in As2O3-treated hamsters in which no testicular toxicities were found. Serum molar concentration of gallium was 32-times higher than that of arsenic in GaAs-treated hamsters. Therefore gallium may play a main role in the testicular toxicity of GaAs in hamsters.
Ann Persson - One of the best experts on this subject based on the ideXlab platform.
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thermal resistance of a nanoscale point contact to an Indium Arsenide nanowire
Applied Physics Letters, 2011Co-Authors: Feng Zhou, Ann Persson, Lars Samuelson, Heiner Linke, Li ShiAbstract:The thermal resistance of a nanoscale point contact to an Indium Arsenide nanowire was experimentally determined to be two orders of magnitude larger than the theoretical prediction based on the diffuse mismatch model for a welded contact. The discrepancy is attributed mainly to a much smaller phonon transmission coefficient for the weak van der Waals contact than for a welded contact. The experiment further suggests the need of careful examination of the structure and defects in the nanowire sample for similar thermal transport measurements of individual nanowires. (C) 2011 American Institute of Physics. [doi:10.1063/1.3623758]
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thermal conductivity of Indium Arsenide nanowires with wurtzite and zinc blende phases
Physical Review B, 2011Co-Authors: Feng Zhou, Arden L Moore, Jessica Bolinsson, Ann Persson, Linus Froberg, Michael T Pettes, Huijun Kong, Lew Rabenberg, Philippe CaroffAbstract:The thermal conductivity of wurtzite and zinc blende Indium Arsenide nanowires was measured using a microfabricated device, with the crystal structure of each sample controlled during growth and determined by transmission electron microscopy. Nanowires of both phases showed a reduction of the thermal conductivity by a factor of 2 or more compared to values reported for zinc blende Indium Arsenide bulk crystals within the measured temperature range. Theoretical models were developed to analyze the measurement results and determine the effect of phase on phonon transport. Branch-specific phonon dispersion data within the discretized first Brillouin zone were calculated from first principles and used in numerical models of volumetric heat capacity and thermal conductivity. The combined results of the experimental and theoretical studies suggest that wurtzite Indium Arsenide possesses similar volumetric heat capacity, weighted average group velocity, weighted average phonon-phonon scattering mean free path, and anharmonic scattering-limited thermal conductivity as the zinc blende phase. Hence, we attribute the differing thermal conductivity values observed in the Indium Arsenide nanowires of different phases to differences in the surface scattering mean free paths between the nanowire samples.
Juekuan Yang - One of the best experts on this subject based on the ideXlab platform.
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Significantly enhanced thermal conductivity of Indium Arsenide nanowires via sulfur passivation.
Scientific reports, 2017Co-Authors: Yucheng Xiong, Hao Tang, Xiaomeng Wang, Yang Zhao, Juekuan YangAbstract:In this work, we experimentally investigated the effect of sulfur passivation on thermal transport in Indium Arsenide (InAs) nanowires. Our measurement results show that thermal conductivity can be enhanced by a ratio up to 159% by sulfur passivation. Current-voltage (I-V) measurements were performed on both unpassivated and S-passivated InAs nanowires to understand the mechanism of thermal conductivity enhancement. We observed a remarkable improvement in electrical conductivity upon sulfur passivation and a significant contribution of electrons to thermal conductivity, which account for the enhanced thermal conductivity of the S-passivated InAs nanowires.
Feng Zhou - One of the best experts on this subject based on the ideXlab platform.
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thermal resistance of a nanoscale point contact to an Indium Arsenide nanowire
Applied Physics Letters, 2011Co-Authors: Feng Zhou, Ann Persson, Lars Samuelson, Heiner Linke, Li ShiAbstract:The thermal resistance of a nanoscale point contact to an Indium Arsenide nanowire was experimentally determined to be two orders of magnitude larger than the theoretical prediction based on the diffuse mismatch model for a welded contact. The discrepancy is attributed mainly to a much smaller phonon transmission coefficient for the weak van der Waals contact than for a welded contact. The experiment further suggests the need of careful examination of the structure and defects in the nanowire sample for similar thermal transport measurements of individual nanowires. (C) 2011 American Institute of Physics. [doi:10.1063/1.3623758]
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thermal conductivity of Indium Arsenide nanowires with wurtzite and zinc blende phases
Physical Review B, 2011Co-Authors: Feng Zhou, Arden L Moore, Jessica Bolinsson, Ann Persson, Linus Froberg, Michael T Pettes, Huijun Kong, Lew Rabenberg, Philippe CaroffAbstract:The thermal conductivity of wurtzite and zinc blende Indium Arsenide nanowires was measured using a microfabricated device, with the crystal structure of each sample controlled during growth and determined by transmission electron microscopy. Nanowires of both phases showed a reduction of the thermal conductivity by a factor of 2 or more compared to values reported for zinc blende Indium Arsenide bulk crystals within the measured temperature range. Theoretical models were developed to analyze the measurement results and determine the effect of phase on phonon transport. Branch-specific phonon dispersion data within the discretized first Brillouin zone were calculated from first principles and used in numerical models of volumetric heat capacity and thermal conductivity. The combined results of the experimental and theoretical studies suggest that wurtzite Indium Arsenide possesses similar volumetric heat capacity, weighted average group velocity, weighted average phonon-phonon scattering mean free path, and anharmonic scattering-limited thermal conductivity as the zinc blende phase. Hence, we attribute the differing thermal conductivity values observed in the Indium Arsenide nanowires of different phases to differences in the surface scattering mean free paths between the nanowire samples.
Noburu Ishinishi - One of the best experts on this subject based on the ideXlab platform.
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testicular toxicity evaluation of arsenic containing binary compound semiconductors gallium Arsenide and Indium Arsenide in hamsters
Toxicology Letters, 1996Co-Authors: Minoru Omura, Akiyo Tanaka, Miyuki Hirata, Yuji Makita, Naohide Inoue, Mangen Zhao, Kaoru Gotoh, Noburu IshinishiAbstract:Abstract The testicular toxicities of gallium Arsenide (GaAs), Indium Arsenide (InAs) and arsenic trioxide (As 2O 3) were examined by repetitive intratracheal instillation using hamsters. GaAs (7.7 mg/kg) and As 2O 3 (1.3 mg/kg) were instilled twice a week a total of 16 times and InAs (7.7 mg/kg) was instilled a total of 14 times. GaAs caused testicular spermatid retention and epididymal sperm reduction, though the degrees were less severe than those in rats shown in our previous experiment. InAs and As2O3 did not show any testicular toxicities. Serum arsenic concentration in GaAs-treated hamsters was less than half of that in As2O3-treated hamsters in which no testicular toxicities were found. Serum molar concentration of gallium was 32-times higher than that of arsenic in GaAs-treated hamsters. Therefore gallium may play a main role in the testicular toxicity of GaAs in hamsters.
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Chronic toxicity of Indium Arsenide and Indium phosphide to the lungs of hamsters.
Fukuoka igaku zasshi = Hukuoka acta medica, 1996Co-Authors: Akiyo Tanaka, Miyuki Hirata, Minoru Omura, Yuji Makita, Naohide Inoue, Akira Hisanaga, Noburu IshinishiAbstract:Chronic toxicity of Indium Arsenide (InAs) and Indium phosphide (InP) was studied in male Syrian golden hamsters which received InAs or InP particles containing a total dose of 7.5 mg of arsenic or phosphorus by intratracheal instillations once a week for 15 weeks. As a control, hamsters were treated with the vehicle, phosphate buffer solution. During their total life span, the cumulative body weight gain of hamsters in the InAs group was suppressed significantly compared with that in the control group, but not in the InP group when compared with that in the control group. Concerning the histopathological findings of the lung, the incidence rates of proteinosis-like lesions, alveolar or bronchiolar cell hyperplasia, pneumonia, emphysema and metaplastic ossification observed in the InAs or InP group were significantly higher than those observed in the control group. From these results, it would seem that InAs and InP produced severe damage to the lungs of hamsters.