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991.
The iron is intrinsically a p-type conductor. When aluminum with three valence electrons is added to the iron, the d-subbands are occupied by electrons, so alloying with the aluminum transforms the iron to the n-type conductor, hence the p-n junction is made possible. Furthermore, when silicon is added to the n-type Fe-Al alloy, this alloy returns to the p-type conductor. Therefore, the thermoelectric p-n junctions with high thermoelectric power have been recognised (figures in % refer to mass contents): Fe(p) – Fe12%Al(n): α=38μV/K and Fe12%Al12%Si(p) – Fe12%/Al(n): Δα=70μV/K. Thermoelectric generation offers the possibility of a gigantic electric power generation utilising low-temperature sources of energy below 700 K such as exhaust heat from the central-station steam-electric plant, solar heat and terrestrial heat. The immense production of electricity by this principle is made possible exclusively by means of the conversion materials consisiting of the iron and iron-based alloy because the generator can be manufactured on an efficient mass production basis, and the alloys mentioned above will meet this requirement. In this paper, the thermoelectric properties of these alloys such as Seebeck coefficient, thermal conductivity and electrical resistivity were experimentally determined in the temperature range between 300 and 700 K to provide basic data on the conversion materials with respect to the thermoelectric generation utilising low-temperature heat sources. 相似文献
992.
We report a case of renal cell carcinoma in whom preoperative interferon-alpha therapy was successful in reducing the primary lesion and the tumor thrombus extending into the inferior vena cava. A 67-year-old man was referred to our hospital because of his right renal mass. We made a diagnosis of a right renal tumor with tumor thrombus by imaging examinations. Because his performance status was 3, a radical operation was considered risky. So we started interferon-alpha therapy. Four months after the start of interferon-alpha therapy, the primary lesion and the tumor thrombus reduced in their size, and the clinical response was evaluated as partial response by the response criteria for urological cancer treatment. Because of improving the performance status and reducing the tumor size, radical nephrectomy and tumor thrombectomy could be performed. Pathological examinations revealed that viable renal cell carcinomas were found only in some small parts of the primary lesion, but not in the tumor thrombus. Postoperatively, no recurrence and metastasis of renal cell carcinoma of the patient have been detected in these two and a half years. 相似文献
993.
Hiroki Shibata Kan Sakamoto Atsushi Ouchi Masaki Kurata 《Journal of Nuclear Science and Technology》2015,52(10):1313-1317
Chemical reactions between stainless steel and boron carbide were investigated using the materials applied for control rods in BWRs in Japan, specifically 304L-type stainless steel and granular boron carbide. The reaction region consisted of 2–4 layers, in which the significant composition variation of each element was detected, especially for B and C. Assuming that the reaction layer growth obeys the parabolic law, the effective rate constant between 304L-type stainless steel and granular boron carbide was evaluated to be approximately one order of magnitude smaller than the previously reported values for boron carbide pellets or powers. This difference might originate from the loose contact between the stainless steel and the granular boron carbide in the present study. Regarding liquefaction progress, the stainless steel components were selectively dissolved in the melt; consequently, the unreacted boron carbide tended to remain. 相似文献
994.
995.
H Kurosu T Maehama T Okada T Yamamoto S Hoshino Y Fukui M Ui O Hazeki T Katada 《Canadian Metallurgical Quarterly》1997,272(39):24252-24256
Phosphoinositide 3-kinase (PI 3-kinase) is a key signaling enzyme implicated in variety of receptor-stimulated cell responses. Receptors with intrinsic or associated tyrosine kinase activity recruit heterodimeric PI 3-kinases consisting of a 110-kDa catalytic subunit (p110) and an 85-kDa regulatory subunit (p85). We separated a PI 3-kinase that could be stimulated by the betagamma subunits of G protein (Gbetagamma) from rat liver. The Gbetagamma-sensitive PI 3-kinase appeared to be a heterodimer consisting of p110beta and p85 (or their related subunits). The stimulation by Gbetagamma was inhibited by the GDP-bound alpha subunit of the inhibitory GTP-binding protein. Moreover, the stimulatory action of Gbetagamma was markedly enhanced by the simultaneous addition of a phosphotyrosyl peptide synthesized according to the amino acid sequence of the insulin receptor substrate-1. Such enzymic properties could be observed with a recombinant p110beta/p85alpha expressed in COS-7 cells with their cDNAs. In contrast, another heterodimeric PI 3-kinase consisting of p110alpha and p85 in the same rat liver, together with a recombinant p110alpha/p85alpha, was not activated by Gbetagamma, although their activities were stimulated by the phosphotyrosyl peptide. These results indicate that p110beta/p85 PI 3-kinase may be regulated in a cooperative manner by two different types of membrane receptors, one possessing tyrosine kinase activity and the other activating GTP-binding proteins. 相似文献
996.
Yu Hashimoto Ryo Yamasaki Senri Ko Eriko Matsuo Yuko Kobayakawa Katsuhisa Masaki Dai Matsuse Noriko Isobe 《International journal of molecular sciences》2022,23(24)
Connexin 30 (Cx30), which forms gap junctions between astrocytes, regulates cell adhesion and migration, and modulates glutamate transport. Cx30 is upregulated on activated astroglia in central nervous system inflammatory lesions, including spinal cord lesions in mutant superoxide dismutase 1 (mSOD1) transgenic amyotrophic lateral sclerosis (ALS) model mice. Here, we investigated the role of Cx30 in mSOD1 mice. Cx30 was highly expressed in the pre-onset stage in mSOD1 mice. mSOD1 mice with knockout (KO) of the Cx30 gene (Cx30KO-mSOD1 mice) showed delayed disease onset and tended to have an extended survival period (log-rank, p = 0.09). At the progressive and end stages of the disease, anterior horn cells were significantly preserved in Cx30KO-mSOD1 mice. In lesions of these mice, glial fibrillary acidic protein/C3-positive inflammatory astroglia were decreased. Additionally, the activation of astrocytes in Cx30KO-mSOD1 mice was reduced compared with mSOD1 mice by gene expression microarray. Furthermore, expression of connexin 43 at the pre-onset stage was downregulated in Cx30KO-mSOD1 mice. These findings suggest that reduced expression of astroglial Cx30 at the early disease stage in ALS model mice protects neurons by attenuating astroglial inflammation. 相似文献
997.
Kunihiro OGAWA Mitsutaka ISOBE Takeo NISHITANI Sadayoshi MURAKAMI Ryosuke SEKI Hideo NUGA Neng PU Masaki OSAKABE LHD Experiment Group 《等离子体科学和技术》2019,21(2):25102-21
Shot-integrated measurement of the triton burnup ratio has been performed in the Large Helical Device. It was reported that the triton burnup ratio, defined as total DT neutron yield divided by total DD neutron yield, increases significantly in inward shifted configurations. To understand the magnetic configuration dependence of the triton burnup ratio, the first orbit loss fraction of 1 MeV tritons is evaluated by means of the Lorentz orbit code for various magnetic configurations. The first orbit loss of 1 MeV tritons is seen at t of less than 10-5 s and loss points of the triton are concentrated on the side of the helical coil case where the magnetic field is relatively weak. The significant decrease of the first orbit loss fraction by 15% is obtained with the inward shift of the magnetic axis position from 3.90 to 3.55 m. It is found that the decrease of first orbit loss is due to the reduction of the first orbit loss of transition and helically trapped tritons. 相似文献
998.
Orthorhombic perovskite-type Ca(Mn1−xTix)O3−δ (0 ≤ x ≤ 0.7) was synthesized at 1173 K for 12 h in a flow of oxygen from a precursor gel prepared using citric acid and ethylene glycol. The Mn3+ ion was generated by substituting a Ti4+ ion in CaMnO3. The average particle size was 100-300 nm and did not depend on x. The lattice constants and the (Mn, Ti)-O distance increased linearly with increasing x. The variation in global instability index (GII) indicated that the instability of the structure increases monotonically with increasing x. Ca(Mn1−xTix)O3−δ was an n-type semiconductor that had its minimum values of electrical resistivity (ρ) and activation energy (Ea) at x = 0.1. Ca(Mn1−xTix)O3−δ (x = 0 and 0.1) exhibited a weak ferromagnetic behavior. The variation in μeff indicated that the spin state of the Mn3+ ion changes from low to high at x = 0.1, then reverts to low in the range of 0.2 ≤ x ≤ 0.7. The variations in ρ and Ea are explained by the number of electrons according to the change in the spin state of the Mn3+ ion. 相似文献
999.
1000.
Masaki Morita Shuntaro Kojima Megumi Ohkubo Hiroyuki Koshino Daisuke Hashizume Go Hirai Keiji Maruoka Mikiko Sodeoka 《Israel journal of chemistry》2017,57(3-4):309-318
We present a full account of our synthetic studies on the racemic DEFGH-ring moiety of physalins, featuring domino ring transformation of a tricyclic key intermediate. We also report the results of a detailed mechanistic examination of the domino ring transformation, as well as a reoptimization of the 2,3-Wittig rearrangement and methylation steps. Furthermore, we have newly established a method for the preparation of an optically active synthetic intermediate by enzymatic kinetic resolution. Our work provides access to both natural and nonnatural right-side physalin structures. 相似文献