Several compounds of rare earth complex oxides containing manganese and titanium were synthesized in Ar, and their crystal structures were analyzed by powder X-ray diffraction data and Rietveld method. Structures of A...Several compounds of rare earth complex oxides containing manganese and titanium were synthesized in Ar, and their crystal structures were analyzed by powder X-ray diffraction data and Rietveld method. Structures of A 0.67 Ln 0.33 Mn 0.33 Ti 0.67 O3 （A=Ca or Sr and Ln=rare earth） were found to have orthorhombic symmetry with the space group Pnma, and their interatomic distances and bond angles were obtained. This space group was also derived from electron microscopic study. Electrical conductivity of Ca 0.67 Ln 0.33 Mn 0.33 Ti 0.67 O3 for several rare earth elements showed a semiconducting property with the activation energy of 0.4 eV. Some of these compounds of the strontium system show the antiferromagnetic properties below 10 K.展开更多
Roles of rare earth oxide (RE2O3) additives in millimeter-wave(MM) sintering of AlN were investigated from the standpoints of phase diagram, heating characteristics of rare earth oxides, and morphology of intergranula...Roles of rare earth oxide (RE2O3) additives in millimeter-wave(MM) sintering of AlN were investigated from the standpoints of phase diagram, heating characteristics of rare earth oxides, and morphology of intergranular oxide phase. In the millimeter-wave sintering of AlN, densification temperature decreased with the decrease of the ionic radius of rare earth ion and was closely related with the eutectic temperature in the RE2O3-Al2O3 binary system. The lowest densification temperature in the millimeter-wave sintering of AlN with Yb2O3 additive was attributed to the largest heating rate of Yb2O3·Al2O3 binary oxide under millimeter-wave radiation. Furthermore, the lowest densification temperature could be attained while selecting the Yb2O3 content so as to form the intergranular phase with the eutectic composition in the Yb2O3-Al2O3 binary system. The result showed good agreement with the above mentioned during the sintering of Si3N4 with Yb2O3-Al2O3 additive. From TEM observation, it was verified that film-like intergranular oxide phase formed under millimeter-wave radiation was favorable for attaining high thermal conductivity in the Yb2O3 added AlNs.展开更多
We propose a new approach to construct an extended Wiener measure using nonstandard analysis by E. Nelson. For the new definition we construct non-standardized convolution of probability measure for independent random...We propose a new approach to construct an extended Wiener measure using nonstandard analysis by E. Nelson. For the new definition we construct non-standardized convolution of probability measure for independent random variables. As an application, we consider a simple calculation of financial time series.展开更多
To unlearn the meaning of a sustainable water resource conservation is now an essential issue in using of sustained, sound, and high-quality water in the world. In this paper, a water quality purification by the Schum...To unlearn the meaning of a sustainable water resource conservation is now an essential issue in using of sustained, sound, and high-quality water in the world. In this paper, a water quality purification by the Schumann frequencies was first considered through the murmuring sound of upper reach at the mountain stream (Kyoto Pref., Japan) regarding the conservation of water resources. Second, water is changing freely and easily accepting the wavelength of all the sounds. We therefore referred to a flow and dynamic equilibrium to realize and understand the water quality purification process. Finally, a “consciousness only Buddhist philosophy” of water quality as an analogical approach was introduced to realize and understand the water purification process. As a result, we have confirmed the water purification capability by Schmann frequencies in an experiment on water quality. And through the experiment, we have realized the importance/significance to find the meaning for a person’s primary meaningless such as 1) meaning connection among life, environment, and economics as a condition of human life, 2) energy, entropy and fluctuation under law of thermodynamics, 3) a metaphor between water quality and mutual possession of the ten worlds based on conscious-only theory, and 4) sense of wonder through the water purification process.展开更多
Single crystal of BaNdMnO4 with I4/mmm was synthesized by a floating zone method. A new phase of BaNdMnO4 was obtained by annealing the single crystal in a reducing atmosphere at 573 K for 10 d. The structural change ...Single crystal of BaNdMnO4 with I4/mmm was synthesized by a floating zone method. A new phase of BaNdMnO4 was obtained by annealing the single crystal in a reducing atmosphere at 573 K for 10 d. The structural change was analyzed by four-circle X-ray diffractometry and transmission electron microscopy. The new phase has an orthorhombic unit cell (Fmmm) of a=0.5486(2)nm, b=0.5484(2)nm, and c=1.3059(2)nm.展开更多
The rare earth manganite BaLn2Mn2O7 (Ln=rare earth element) has a Sr3Ti2O7-type layered perovskite structure with double-block oxygen octahedra belonging to the Ruddlesden-Popper-type homologous series AO(ABO3)2. In P...The rare earth manganite BaLn2Mn2O7 (Ln=rare earth element) has a Sr3Ti2O7-type layered perovskite structure with double-block oxygen octahedra belonging to the Ruddlesden-Popper-type homologous series AO(ABO3)2. In Pr-manganite, a novel phase transition was first observed in situ at 1040 K by a thermal transmission electron microscope. At 1040 K, reflections began to split along the c-direction in the selected area diffraction pattern. This indicates that a new phase appears in the original phase matrix; the c length of the new phase is 1.5% longer than that of the original phase. After about 5 min, the original phase disappears. No change in the crystal symmetry (space group I4/mmm) is observed above 1040 K.展开更多
The existing phases in BaxGd1-xMnO3 solid solution system (0≦x≦1) were studied by analyzing the detailed crystal structure of each composition from the results of the Rietveld method using powder X-ray diffraction d...The existing phases in BaxGd1-xMnO3 solid solution system (0≦x≦1) were studied by analyzing the detailed crystal structure of each composition from the results of the Rietveld method using powder X-ray diffraction data. For a small substitution of Ba for Gd (0≦x<0.1), the orthorhombic phase with a perovskite type structure (Pnma space group) was stably formed and this fact was supported by the electron diffraction data. There existed an intermediate phase of Ba0.33Gd0.67MnO3, which was characterized as the tetragonal phase with perovskite structure. The composition range of this phase was narrow and almost line compound. Between the regions of these phases, there ex- isted two-phase region. There was also a two-phase region between the intermediate tetragonal phase and BaMnO3. Measurement of electrical conductivities of these orthorhombic solid solutions and tetragonal phases showed semiconducting behaviors for both phases and the existence of the phase transition at high temperature for the orthorhombic phase. The transition temperature decreased as the Ba content increased.展开更多
Temperature is often considered as a primary factor for microbial decomposition of soil organic carbon. Boreal forests are the large terrestrial carbon pool: if carbon stored in this region is transferred to the atmos...Temperature is often considered as a primary factor for microbial decomposition of soil organic carbon. Boreal forests are the large terrestrial carbon pool: if carbon stored in this region is transferred to the atmosphere as CO2 by a warming-induced acceleration of its decomposition, there will be positive feedback to global warming. It is reported that real issue regarding the release of carbon from soils to the atmosphere is how natural factors interact to influence decomposition of soil organic matter, so we observed mass losses (indicating decomposition rates) from litter and litterfall in a Northern Fennoscandia forest over 3 years under natural conditions. Our field survey has demonstrated that mass losses from most kinds of sample had moderate correlation with the temperature. Of the various samples, the canopy-gap litter alone had a greater rate (~70%) of mass loss. It is at least necessary to make a clear distinction of monitoring sites (under the canopy and in the canopy gap) when discussing the effect of climate on soil CO2 release from high-latitude forests. Though temperature, soil moisture and soil properties are prioritized in the issue of soil CO2 release, our results suggest that the fungi/bacteria rate and the wind-related mix/fragmentation are also important factors to be considered;however, this speculation is just tentative, and more detail research is called for.展开更多
Seaweeds are not used as much for edible use although many kinds of seaweed are collected in Sri Lanka.The objective of this study was to develop high quality bread using seaweed,Kappaphycus alvarezii collected from S...Seaweeds are not used as much for edible use although many kinds of seaweed are collected in Sri Lanka.The objective of this study was to develop high quality bread using seaweed,Kappaphycus alvarezii collected from Sri Lanka,and wild yeast,Saccharomyces cerevisiae isolated from nectarine in Japan.Dietary fiber in K.alvarezii,Japanese sea weeds,Wakame and Aosa contained 48.1,31.7 and 29.1 g/100 g,respectively.The amount of total organic acid increased in garlic bread compared to bread without garlic.The best swelling properties were evident in the bread with K.alvarezii(0.5%)and garlic.The bread including K.alvarezii increased the fermentative power of wild yeast while the addition of garlic increased the degree of swelling of the dough.In the sensory testing,the bread with K.alvarezii(0.5%)and garlic was favored for the fineness of its texture and had the most preferred texture.It is possible to develop seaweed bread that is rich in dietary fiber and has excellent flavor by adding a suitable amount of garlic during the fermentation process.展开更多
The mechanical properties of polyvinyl alcohol (PVA) films prepared by evaporating water from freeze/thaw cycled gel were investigated as a function of the number of freeze/thaw cycles. The maximum stress of the PVA f...The mechanical properties of polyvinyl alcohol (PVA) films prepared by evaporating water from freeze/thaw cycled gel were investigated as a function of the number of freeze/thaw cycles. The maximum stress of the PVA film prepared by freeze/thaw cycling was larger than that prepared without the freeze/thaw cycle process. The largest maximum stress was 46.2 MPa for a film prepared with 10 freeze/thaw cycles, which was twice as large as that for a cast PVA film without freeze/thaw cycling (22.3 MPa). This is due to the formation of small crystallites during the freeze/thaw cycle process. Furthermore, when the film was annealed at 130°C, the maximum stress was as high as 181 MPa which was comparable to that for PVA films prepared using additives. The crystallinity is not the main factor that determines the maximum stress for either the non-annealed or annealed freeze/thaw cycled films, but the glass transition temperature is well correlated with the maximum stress, irrespective of the annealing process. This is due to the different molecular morphology;the non-annealed freeze/thaw cycled film consists of many small crystallites, but the annealed film consists of larger crystallites formed during the annealing process.展开更多
The size and weight fraction of crystals of pure ice or dimethylsulfoxide (DMSO) in poly(vinyl alcohol) (PVA) gel prepared from a mixed solvent of DMSO/water were determined from melting peaks observed by differential...The size and weight fraction of crystals of pure ice or dimethylsulfoxide (DMSO) in poly(vinyl alcohol) (PVA) gel prepared from a mixed solvent of DMSO/water were determined from melting peaks observed by differential scanning calorimetry (DSC). The depression of the melting point with respect to the equilibrium melting point and the melting enthalpy gave the crystal size and weight fraction, respectively. The sizes were in the range of a few nm to tens of nm, depending on the composition ratio of the mixed solvent (DMSO/water) and the polymer concentration. Based on the weight fraction, the critical condition at which the whole solvent became non-freezable was estimated, and it was found to depend on both the PVA concentration and the DMSO/water ratio. When the solvent was pure water, the critical PVA concentration was as high as 86.4 wt%, while for pure DMSO solvent it was 50.1 wt%.展开更多
In recent years, application of carbon-based nano material to electrode material has been paid attention, however, due to its higher cost, it would be difficult to put it into practical use. Then, we have proposed to ...In recent years, application of carbon-based nano material to electrode material has been paid attention, however, due to its higher cost, it would be difficult to put it into practical use. Then, we have proposed to make nano carbon fiber with lower production cost. The purpose of our research was, to apply our nano carbon fiber to electrical double-layer capacitor electrode. We used cotton candy method to make nano fiber, and applied microwave heating for carbonization. By applying nano carbon fiber to electrical double-layer capacitor electrode, we got results that thicker electrode containing nano carbon fiber leads to lower resistance value, compared with electrode without containing nano carbon fiber. From this result, it was indicated that by containing nano carbon fiber, the electric bypass was formed in the electrode.展开更多
This paper compares the statistical properties of time-varying causality tests when errors of variables have multivariate stochastic volatility (SV). The time-varying causal-ity tests in this paper are based on a logi...This paper compares the statistical properties of time-varying causality tests when errors of variables have multivariate stochastic volatility (SV). The time-varying causal-ity tests in this paper are based on a logistic smooth transition autoregressive model. The compared time-varying causality tests include asymptotic tests, heteroskedasticity-robust tests, and tests using wild bootstrap. Our simulation results show that asymptotic tests and heteroskedasticity-robust counterparts have size distortions under multivariate SV, whereas tests using wild bootstrap have better size properties regardless of type of error. In particular, the time-varying causality test with first-order Taylor approximation using wild bootstrap has better statistical properties.展开更多
Since ancient times,humans have bred several plants that we rely on today.However,little is known about the divergence of most of these plants.In the present study,we investigated the divergence of Mibuna(Brassica rap...Since ancient times,humans have bred several plants that we rely on today.However,little is known about the divergence of most of these plants.In the present study,we investigated the divergence of Mibuna(Brassica rapa L.subsp.nipposinica L.H.Bailey),a traditional leafy vegetable in Kyoto(Japan),by combining genetic analysis and a survey of ancient literature.Mibuna is considered to have been bred 200 years ago from Mizuna,another traditional leafy vegetable in Kyoto.Mibuna has simple spatulate leaves,whereas Mizuna has characteristic serrated leaves.The quantitative trait loci(QTL)and gene expression analyses suggested that the downregulation of BrTCP15 expression contributed to the change in the leaf shape from serrated to simple spatulate.Interestingly,the SNP analysis indicated that the genomic region containing the BrTCP15 locus was transferred to Mibuna by introgression.Furthermore,we conducted a survey of ancient literature to reveal the divergence of Mibuna and found that hybridization between Mizuna and a simple-leaved turnip might have occurred in the past.Indeed,the genomic analysis of multiple turnip cultivars showed that one of the cultivars,Murasakihime,has almost the same sequence in the BrTCP15 region as Mibuna.These results suggest that the hybridization between Mizuna and turnip has resulted in the establishment of Mibuna.展开更多
Improving grain quality is a primary objective in contemporary rice breeding.Japanese modern rice breeding has developed two different types of rice,eating and sake-brewing rice,with different grain characteristics,in...Improving grain quality is a primary objective in contemporary rice breeding.Japanese modern rice breeding has developed two different types of rice,eating and sake-brewing rice,with different grain characteristics,indicating the selection of variant gene alleles during the breeding process.Given the critical importance of promptly and efficiently identifying genes selected in past breeding for future molecular breeding,we conducted genome scans for divergence,genome-wide association studies,and map-based cloning.Consequently,we successfully identified two genes,OsMnS and OsWOX9D,both contributing to rice grain traits.OsMnS encodes a mannan synthase that increases the white core frequency in the endosperm,a desirable trait for sake brewing but decreases the grain appearance quality.OsWOX9D encodes a grass-specific homeobox-containing transcription factor,which enhances grain width for better sake brewing.Furthermore,haplotype analysis revealed that their defective alleles were selected in East Asia,but not Europe,during modern improvement.In addition,our analyses indicate that a reduction in grain mannan content during African rice domestication may also be caused a defective OsMnS allele due to breeding selection.This study not only reveals the delicate balance between grain appearance quality and nutrition in rice but also provides a new strategy for isolating causal genes underlying complex traits,based on the concept of“breeding-assisted genomics”in plants.展开更多
By revisiting the three stage theory for the progress of science proposed by Taketani in 1942,the footmarks of fluidization research are examined.The bubbling and fast fluidization issues were emphasized so that the f...By revisiting the three stage theory for the progress of science proposed by Taketani in 1942,the footmarks of fluidization research are examined.The bubbling and fast fluidization issues were emphasized so that the future of fluidization research can be discussed among scientists and engineers in a wider perspective.The first cycle of fluidization research was started in the early 1940s by an initial stage of phenomenology.The second stage of structural studies was kicked off in the early 1950s with the introduction of the two phase theory.The third stage of essential studies occurred in the early 1960s in the form of bubble hydrodynamics.The second cycle,which confirmed the aforementioned three stages closed at the turn of the century,established a general understanding of suspension structures including agglomerating fluidization,bubbling,turbulent and fast fluidizations and pneumatic transport;also established powerful measurement and numerical simulation tools.After a general remark on science,technology and society issues the interactions between fluidization technology and science are revisited.Our future directions are discussed including the tasks in the third cycle,particularly in its phenomenology stage where strong motivation and intention are always necessary,in relation also to the green reforming of the present technology.A generalized definition of'fluidization'is proposed to extend fluidization principle into much wider scientific fields,which would be effective also for wider collaborations.展开更多
We report the experimental demonstration of transform-limited sub-6 fs pulses at an optimal central wavelength by a tunable noncollinear optical parametric amplification(NOPA) source. Meanwhile, a white light continuu...We report the experimental demonstration of transform-limited sub-6 fs pulses at an optimal central wavelength by a tunable noncollinear optical parametric amplification(NOPA) source. Meanwhile, a white light continuum in the near-infrared(NIR) range from 900 to 1100 nm is also successfully generated by focusing the unconverted800 nm beam during NOPA generation on a sapphire rod. Both visible-pump/visible-probe and visible-pump/NIR-probe experiments are realized using the same laser system. As examples, ultrafast photo-induced exciton dynamics inside two kinds of materials are investigated by the visible-pump/visible-probe and visible-pump/NIR-probe spectroscopy, respectively.展开更多
基金Foundation ite ms:Project supported bythe Grant-in-Aidfor Scientific Research (C) (18560662) bythe Japan Societyfor the Promotion of Science
文摘Several compounds of rare earth complex oxides containing manganese and titanium were synthesized in Ar, and their crystal structures were analyzed by powder X-ray diffraction data and Rietveld method. Structures of A 0.67 Ln 0.33 Mn 0.33 Ti 0.67 O3 （A=Ca or Sr and Ln=rare earth） were found to have orthorhombic symmetry with the space group Pnma, and their interatomic distances and bond angles were obtained. This space group was also derived from electron microscopic study. Electrical conductivity of Ca 0.67 Ln 0.33 Mn 0.33 Ti 0.67 O3 for several rare earth elements showed a semiconducting property with the activation energy of 0.4 eV. Some of these compounds of the strontium system show the antiferromagnetic properties below 10 K.
基金the Grant-in-Aid for Scientific Research on Priority Area (18070004) of MEXT, Japan
文摘Roles of rare earth oxide (RE2O3) additives in millimeter-wave(MM) sintering of AlN were investigated from the standpoints of phase diagram, heating characteristics of rare earth oxides, and morphology of intergranular oxide phase. In the millimeter-wave sintering of AlN, densification temperature decreased with the decrease of the ionic radius of rare earth ion and was closely related with the eutectic temperature in the RE2O3-Al2O3 binary system. The lowest densification temperature in the millimeter-wave sintering of AlN with Yb2O3 additive was attributed to the largest heating rate of Yb2O3·Al2O3 binary oxide under millimeter-wave radiation. Furthermore, the lowest densification temperature could be attained while selecting the Yb2O3 content so as to form the intergranular phase with the eutectic composition in the Yb2O3-Al2O3 binary system. The result showed good agreement with the above mentioned during the sintering of Si3N4 with Yb2O3-Al2O3 additive. From TEM observation, it was verified that film-like intergranular oxide phase formed under millimeter-wave radiation was favorable for attaining high thermal conductivity in the Yb2O3 added AlNs.
文摘We propose a new approach to construct an extended Wiener measure using nonstandard analysis by E. Nelson. For the new definition we construct non-standardized convolution of probability measure for independent random variables. As an application, we consider a simple calculation of financial time series.
文摘To unlearn the meaning of a sustainable water resource conservation is now an essential issue in using of sustained, sound, and high-quality water in the world. In this paper, a water quality purification by the Schumann frequencies was first considered through the murmuring sound of upper reach at the mountain stream (Kyoto Pref., Japan) regarding the conservation of water resources. Second, water is changing freely and easily accepting the wavelength of all the sounds. We therefore referred to a flow and dynamic equilibrium to realize and understand the water quality purification process. Finally, a “consciousness only Buddhist philosophy” of water quality as an analogical approach was introduced to realize and understand the water purification process. As a result, we have confirmed the water purification capability by Schmann frequencies in an experiment on water quality. And through the experiment, we have realized the importance/significance to find the meaning for a person’s primary meaningless such as 1) meaning connection among life, environment, and economics as a condition of human life, 2) energy, entropy and fluctuation under law of thermodynamics, 3) a metaphor between water quality and mutual possession of the ten worlds based on conscious-only theory, and 4) sense of wonder through the water purification process.
基金a Grant-in Aidfor Scientific Research (c) (18560662) from the Japan Society for the Promotion of Science
文摘Single crystal of BaNdMnO4 with I4/mmm was synthesized by a floating zone method. A new phase of BaNdMnO4 was obtained by annealing the single crystal in a reducing atmosphere at 573 K for 10 d. The structural change was analyzed by four-circle X-ray diffractometry and transmission electron microscopy. The new phase has an orthorhombic unit cell (Fmmm) of a=0.5486(2)nm, b=0.5484(2)nm, and c=1.3059(2)nm.
基金Project supported by a Grant-in Aid for Scientific Research (c) No. 18560662 by Japan Society for the Promotion of Science
文摘The rare earth manganite BaLn2Mn2O7 (Ln=rare earth element) has a Sr3Ti2O7-type layered perovskite structure with double-block oxygen octahedra belonging to the Ruddlesden-Popper-type homologous series AO(ABO3)2. In Pr-manganite, a novel phase transition was first observed in situ at 1040 K by a thermal transmission electron microscope. At 1040 K, reflections began to split along the c-direction in the selected area diffraction pattern. This indicates that a new phase appears in the original phase matrix; the c length of the new phase is 1.5% longer than that of the original phase. After about 5 min, the original phase disappears. No change in the crystal symmetry (space group I4/mmm) is observed above 1040 K.
基金the Grant-in-Aid for Scientific Research (C) (18560662) by the Japan Society for the Promotion of Science
文摘The existing phases in BaxGd1-xMnO3 solid solution system (0≦x≦1) were studied by analyzing the detailed crystal structure of each composition from the results of the Rietveld method using powder X-ray diffraction data. For a small substitution of Ba for Gd (0≦x<0.1), the orthorhombic phase with a perovskite type structure (Pnma space group) was stably formed and this fact was supported by the electron diffraction data. There existed an intermediate phase of Ba0.33Gd0.67MnO3, which was characterized as the tetragonal phase with perovskite structure. The composition range of this phase was narrow and almost line compound. Between the regions of these phases, there ex- isted two-phase region. There was also a two-phase region between the intermediate tetragonal phase and BaMnO3. Measurement of electrical conductivities of these orthorhombic solid solutions and tetragonal phases showed semiconducting behaviors for both phases and the existence of the phase transition at high temperature for the orthorhombic phase. The transition temperature decreased as the Ba content increased.
文摘Temperature is often considered as a primary factor for microbial decomposition of soil organic carbon. Boreal forests are the large terrestrial carbon pool: if carbon stored in this region is transferred to the atmosphere as CO2 by a warming-induced acceleration of its decomposition, there will be positive feedback to global warming. It is reported that real issue regarding the release of carbon from soils to the atmosphere is how natural factors interact to influence decomposition of soil organic matter, so we observed mass losses (indicating decomposition rates) from litter and litterfall in a Northern Fennoscandia forest over 3 years under natural conditions. Our field survey has demonstrated that mass losses from most kinds of sample had moderate correlation with the temperature. Of the various samples, the canopy-gap litter alone had a greater rate (~70%) of mass loss. It is at least necessary to make a clear distinction of monitoring sites (under the canopy and in the canopy gap) when discussing the effect of climate on soil CO2 release from high-latitude forests. Though temperature, soil moisture and soil properties are prioritized in the issue of soil CO2 release, our results suggest that the fungi/bacteria rate and the wind-related mix/fragmentation are also important factors to be considered;however, this speculation is just tentative, and more detail research is called for.
文摘Seaweeds are not used as much for edible use although many kinds of seaweed are collected in Sri Lanka.The objective of this study was to develop high quality bread using seaweed,Kappaphycus alvarezii collected from Sri Lanka,and wild yeast,Saccharomyces cerevisiae isolated from nectarine in Japan.Dietary fiber in K.alvarezii,Japanese sea weeds,Wakame and Aosa contained 48.1,31.7 and 29.1 g/100 g,respectively.The amount of total organic acid increased in garlic bread compared to bread without garlic.The best swelling properties were evident in the bread with K.alvarezii(0.5%)and garlic.The bread including K.alvarezii increased the fermentative power of wild yeast while the addition of garlic increased the degree of swelling of the dough.In the sensory testing,the bread with K.alvarezii(0.5%)and garlic was favored for the fineness of its texture and had the most preferred texture.It is possible to develop seaweed bread that is rich in dietary fiber and has excellent flavor by adding a suitable amount of garlic during the fermentation process.
文摘The mechanical properties of polyvinyl alcohol (PVA) films prepared by evaporating water from freeze/thaw cycled gel were investigated as a function of the number of freeze/thaw cycles. The maximum stress of the PVA film prepared by freeze/thaw cycling was larger than that prepared without the freeze/thaw cycle process. The largest maximum stress was 46.2 MPa for a film prepared with 10 freeze/thaw cycles, which was twice as large as that for a cast PVA film without freeze/thaw cycling (22.3 MPa). This is due to the formation of small crystallites during the freeze/thaw cycle process. Furthermore, when the film was annealed at 130°C, the maximum stress was as high as 181 MPa which was comparable to that for PVA films prepared using additives. The crystallinity is not the main factor that determines the maximum stress for either the non-annealed or annealed freeze/thaw cycled films, but the glass transition temperature is well correlated with the maximum stress, irrespective of the annealing process. This is due to the different molecular morphology;the non-annealed freeze/thaw cycled film consists of many small crystallites, but the annealed film consists of larger crystallites formed during the annealing process.
文摘The size and weight fraction of crystals of pure ice or dimethylsulfoxide (DMSO) in poly(vinyl alcohol) (PVA) gel prepared from a mixed solvent of DMSO/water were determined from melting peaks observed by differential scanning calorimetry (DSC). The depression of the melting point with respect to the equilibrium melting point and the melting enthalpy gave the crystal size and weight fraction, respectively. The sizes were in the range of a few nm to tens of nm, depending on the composition ratio of the mixed solvent (DMSO/water) and the polymer concentration. Based on the weight fraction, the critical condition at which the whole solvent became non-freezable was estimated, and it was found to depend on both the PVA concentration and the DMSO/water ratio. When the solvent was pure water, the critical PVA concentration was as high as 86.4 wt%, while for pure DMSO solvent it was 50.1 wt%.
文摘In recent years, application of carbon-based nano material to electrode material has been paid attention, however, due to its higher cost, it would be difficult to put it into practical use. Then, we have proposed to make nano carbon fiber with lower production cost. The purpose of our research was, to apply our nano carbon fiber to electrical double-layer capacitor electrode. We used cotton candy method to make nano fiber, and applied microwave heating for carbonization. By applying nano carbon fiber to electrical double-layer capacitor electrode, we got results that thicker electrode containing nano carbon fiber leads to lower resistance value, compared with electrode without containing nano carbon fiber. From this result, it was indicated that by containing nano carbon fiber, the electric bypass was formed in the electrode.
文摘This paper compares the statistical properties of time-varying causality tests when errors of variables have multivariate stochastic volatility (SV). The time-varying causal-ity tests in this paper are based on a logistic smooth transition autoregressive model. The compared time-varying causality tests include asymptotic tests, heteroskedasticity-robust tests, and tests using wild bootstrap. Our simulation results show that asymptotic tests and heteroskedasticity-robust counterparts have size distortions under multivariate SV, whereas tests using wild bootstrap have better size properties regardless of type of error. In particular, the time-varying causality test with first-order Taylor approximation using wild bootstrap has better statistical properties.
基金This research was supported by grants in aid from the Japan Society for the Promotion of Science(KAKENHI grant numbers 16H01472 and 18H04787)the MEXT-Supported Program for the Strategic Research Foundation at Private Universities(grant number S1511023)from the Ministry of Education,Culture,Sports,Science,and Technology of Japan to S.K+2 种基金This work was also financially supported by the Sasakawa Scientific Research Grant from The Japan Science Society to Y.KThis study was supported by a Joint Usage/Research program of the Center for Ecological Research,Kyoto University,the Ministry of Education,Culture,Sports,Science,and Technology of Japan(MEXT)[Grant-in-Aid for Scientific Research on Innovative Areas(19H04870)]Research Funding for the Computational Software Supporting Program from Meiji University.
文摘Since ancient times,humans have bred several plants that we rely on today.However,little is known about the divergence of most of these plants.In the present study,we investigated the divergence of Mibuna(Brassica rapa L.subsp.nipposinica L.H.Bailey),a traditional leafy vegetable in Kyoto(Japan),by combining genetic analysis and a survey of ancient literature.Mibuna is considered to have been bred 200 years ago from Mizuna,another traditional leafy vegetable in Kyoto.Mibuna has simple spatulate leaves,whereas Mizuna has characteristic serrated leaves.The quantitative trait loci(QTL)and gene expression analyses suggested that the downregulation of BrTCP15 expression contributed to the change in the leaf shape from serrated to simple spatulate.Interestingly,the SNP analysis indicated that the genomic region containing the BrTCP15 locus was transferred to Mibuna by introgression.Furthermore,we conducted a survey of ancient literature to reveal the divergence of Mibuna and found that hybridization between Mizuna and a simple-leaved turnip might have occurred in the past.Indeed,the genomic analysis of multiple turnip cultivars showed that one of the cultivars,Murasakihime,has almost the same sequence in the BrTCP15 region as Mibuna.These results suggest that the hybridization between Mizuna and turnip has resulted in the establishment of Mibuna.
文摘Improving grain quality is a primary objective in contemporary rice breeding.Japanese modern rice breeding has developed two different types of rice,eating and sake-brewing rice,with different grain characteristics,indicating the selection of variant gene alleles during the breeding process.Given the critical importance of promptly and efficiently identifying genes selected in past breeding for future molecular breeding,we conducted genome scans for divergence,genome-wide association studies,and map-based cloning.Consequently,we successfully identified two genes,OsMnS and OsWOX9D,both contributing to rice grain traits.OsMnS encodes a mannan synthase that increases the white core frequency in the endosperm,a desirable trait for sake brewing but decreases the grain appearance quality.OsWOX9D encodes a grass-specific homeobox-containing transcription factor,which enhances grain width for better sake brewing.Furthermore,haplotype analysis revealed that their defective alleles were selected in East Asia,but not Europe,during modern improvement.In addition,our analyses indicate that a reduction in grain mannan content during African rice domestication may also be caused a defective OsMnS allele due to breeding selection.This study not only reveals the delicate balance between grain appearance quality and nutrition in rice but also provides a new strategy for isolating causal genes underlying complex traits,based on the concept of“breeding-assisted genomics”in plants.
文摘By revisiting the three stage theory for the progress of science proposed by Taketani in 1942,the footmarks of fluidization research are examined.The bubbling and fast fluidization issues were emphasized so that the future of fluidization research can be discussed among scientists and engineers in a wider perspective.The first cycle of fluidization research was started in the early 1940s by an initial stage of phenomenology.The second stage of structural studies was kicked off in the early 1950s with the introduction of the two phase theory.The third stage of essential studies occurred in the early 1960s in the form of bubble hydrodynamics.The second cycle,which confirmed the aforementioned three stages closed at the turn of the century,established a general understanding of suspension structures including agglomerating fluidization,bubbling,turbulent and fast fluidizations and pneumatic transport;also established powerful measurement and numerical simulation tools.After a general remark on science,technology and society issues the interactions between fluidization technology and science are revisited.Our future directions are discussed including the tasks in the third cycle,particularly in its phenomenology stage where strong motivation and intention are always necessary,in relation also to the green reforming of the present technology.A generalized definition of'fluidization'is proposed to extend fluidization principle into much wider scientific fields,which would be effective also for wider collaborations.
基金partly financially supported by the 100 Talents Program of CASthe National Basic Research Program of China(Grant No.2011CB808101)the National Natural Science Foundation of China(Grant No.61475169,61221064)
文摘We report the experimental demonstration of transform-limited sub-6 fs pulses at an optimal central wavelength by a tunable noncollinear optical parametric amplification(NOPA) source. Meanwhile, a white light continuum in the near-infrared(NIR) range from 900 to 1100 nm is also successfully generated by focusing the unconverted800 nm beam during NOPA generation on a sapphire rod. Both visible-pump/visible-probe and visible-pump/NIR-probe experiments are realized using the same laser system. As examples, ultrafast photo-induced exciton dynamics inside two kinds of materials are investigated by the visible-pump/visible-probe and visible-pump/NIR-probe spectroscopy, respectively.
