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61.
62.
Eleven new far-infrared (FIR) laser lines have been observed from CH3OH pumped by a CO2laser. These lines are ranged from 78 to 694 μm and are obtained by using a copper waveguide cavity.  相似文献   
63.
Physicochemical properties of five sweetpotato starches differing in gelatinization temperature were examined. The gelatinization temperature of Koganesengan starch, an ordinary cultivar of sweetpotato in Japan, was 73.6°C, whereas those of the other starches were measured to be 71.6°C for Kyukei 96162–1, 65.8°C for Kyushu No.127, 63.9°C for Kyukei 240, and 54.9°C for Quick Sweet. Some relationships of the primary structural properties with the gelatinization temperature have been found. As the gelatinization temperature decreased: i) the content of phosphate groups attached to the glucosyl residues decreased, ii) the amylose content, which was determined as difference in long chains of debranched original starch and of its amylopectin, decreased, iii) the proportion of unit chains with DP > 100 in the amylopectin fraction increased, iv) the proportion of unit chains with DP 6 to 10 in the amylopectin fraction increased, whereas that of unit chains with DP 12 to 24 decreased, v) the B‐type crystallinity of the starch granules was enhanced, and vi) the proportion of longer chains constituting each Nägeli amylodextrin increased. Moreover, it was found that thin pastes of the low temperature‐gelatinizing starches retrograded slower during cold storage than the ordinary starch. Among the starches, Quick Sweet starch granules, having the lowest gelatinization temperature, were digested rapidly by pancreatin.  相似文献   
64.
The effect of fluidized bed reactor in autothermal CO2 reforming of methane over NiO–MgO solid solution catalysts was investigated by comparing with fixed bed reactor. Methane conversion to syngas was drastically enhanced by using a fluidized bed reactor. The catalyst was reduced and oxidized repeatedly in fluidized bed reactor during the reaction. The enhancement of methane conversion is related to the catalyst reducibility.  相似文献   
65.
为了应对近年来提高设备生产性能的要求,高运转率和稳定运转成为重要课题。一方面,钢铁厂的主要设备经30-40年的运转,极有必要有效诊断设备的磨损程度,适时进行检修。因此,从设备的稳定和安全运转来看,设备磨损有效诊断技术的发明则成为重要课题。为应对这一问题,JFE钢铁集团(股份)(日本大型钢铁厂,在日本国内仅次于新日本制铁...  相似文献   
66.
We have successfully developed a low-noise and high-power Pr3+-doped fluoride amplifier (PDFA) module with a cascade configuration. The maximum signal gain and noise figure were 40.6 dB and 5 dB, respectively. An output power of 20.1 dBm was achieved at an input signal power of 0 dBm. We confirm that this PDFA module performs well from experimental results on its use in a 40 channel AM-VSB video signal transmission and a 10 Gbit/s digital transmission  相似文献   
67.
68.
Cerebral blood flow (CBF) and response to acetazolamide were measured during the acute, subacute, and chronic stages after aneurysmal subarachnoid hemorrhage and correlated with symptomatic vasospasm and clinical outcome in 45 patients who underwent early clipping of ruptured cerebral aneurysms, of whom 18 had symptomatic vasospasm and 27 did not. Xenon-enhanced computed tomography was used to measure CBF in both groups during the acute, subacute, and chronic stages, defined as days 0-4, 5-20, and > or = 21, respectively. Vasoresponse was assessed by the CBF increase in response to 1 g of acetazolamide administered after the baseline CBF study, except in the subacute stage of patients with symptomatic vasospasm. Outcome was scored based on activities of daily living 2-3 months after subarachnoid hemorrhage. CBF values and the response to acetazolamide were preserved during the acute stage but CBF values fell considerably below control values during the subacute stage in patients with vasospasm. The regions with flow values below 15 ml/100 g/min subsequently converted to infarction and the regions with those above 19 ml/100 g/min remained intact without infarction. During the chronic stage, low CBF persisted, but the response to acetazolamide was higher than that of the control group. Outcome scores were good and fair. CBF values were normal during all stages in patients without vasospasm. The response to acetazolamide fell transiently during the subacute stage. All outcome scores were excellent. In conclusion, the CBF informations soon after the onset of symptomatic vasospasm are useful to predict a reversibility of ischemic brain tissue and a final outcome. We suggest that vasospasm may cause a pathological or ischemic insult to brain tissue during the subacute stage, and the brain may remain metabolically depressed thereafter, leading to a poor outcome. Even clinically asymptomatic patients may suffer mildly vasospastic or ischemic conditions during the subacute stage.  相似文献   
69.
Megakaryocytes are unique haemopoietic cells which undergo DNA replication, giving rise to polyploid cells. However, little is known about the mechanism of megakaryocytic polyploidization. To address this issue, we used the human megakaryocytic cell line Meg-J. In the presence of K-252a (an indolocarbasole derivative), Meg-J cells stopped proliferation and exhibited additional megakaryocytic features, including morphological changes, polyploidization, and increases in the levels of surface expression of platelet glycoprotein (GP) IIb/IIa and GPIb. Thrombopoietin (TPO) promoted the K-2 52a-induced polyploidization and megakaryocytic differentiation. In the process of K-252a-induced polyploidization, levels of expression of both cdc2 and cyclin B1 were elevated transiently and subsequently decreased. This suggested that the polyploidization process in Meg-J cells was at least in part associated with a transient elevation and subsequent decrease in the expression of cdc2/cyclin B1 complex, a critical kinase involved in G2/M cell cycle transition.  相似文献   
70.
Two different forms of rutile-type iridium oxide catalysts were prepared: IrO2-coated titanium plate electrocatalysts prepared by a dip-coating method (IrO2/Ti) and iridium oxide nanoparticles (IrO2) prepared by a wet method, the Adams fusion method. The catalytic behavior of the oxygen reduction reaction (ORR) was evaluated by cyclic voltammetry in 0.5 M H2SO4 at 60 °C. Both catalysts were found to exhibit considerable activity for the ORR; however, the former oxide electrodes showed higher activity than the latter ones. All the IrO2/Ti catalyst electrodes heat-treated at a temperature between 400 °C and 550 °C showed ca. 0.84 V (vs. RHE) of the onset potential for the ORR, EORR, where the reduction current of oxygen had begun to be observed during the cathodic potential sweep of the test electrodes. It has been confirmed clearly that IrO2, but neither metallic Ir nor the hydrated IrO2, behaves as an active catalyst for the ORR in an acidic solution. It was also demonstrated that the enlargement of the surface area of the IrO2/Ti with the help of lanthanum is effective for the enhancement of the catalytic activity in the reaction.  相似文献   
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