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1.
The present paper includes experimental and analytical data on the fracture properties of a nickel-iron superalloy, a ferromagnetic austenite, at 4 K in magnetic fields of 0 and 6 T. The tensile, notch tensile and small punch tests are employed. A finite element analysis is also performed to convert the experimentally measured load-displacement data into useful engineering information. To interpret the results we review the available theory of the influence of magnetic field on the stress intensity factor for a crack in ferromagnetic materials.  相似文献   
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Metallothionein (MT) synthesis induced by the inflammatory cytokines, interleukin-6 (IL-6) and tumor necrosis factor-alpha (TNF), was studied in vivo. Administration of recombinant human IL-6 or TNF to rats caused the acute phase responses including rapid decreases in plasma zinc (Zn), and increases in plasma copper (Cu) and ceruloplasmin. Hepatic concentration of MT-I, one of MT isoforms, began to increase within 3 h after the injection of IL-6 or TNF. In IL-6-treated rats, MT-I concentration in liver reached a maximum level at 12 h and decreased with a transient rebound, whereas, in TNF-treated rats, a high level of MT-I lasted for about 48 h. MT-II, the other MT isoform, was induced more than MT-I in liver by both cytokines. MT-I was also induced in lung and heart by TNF, but little by IL-6. The data suggest that IL-6 may be responsible for MT synthesis in liver, whereas TNF may be responsible not only in liver but also in lung and heart. Furthermore plasma concentration of MT did not always reflect the enhanced concentration of MT by TNF and IL-6 in liver, suggesting involvement of many factors influencing plasma MT levels. The interrelation between IL-6 and TNF for MT synthesis has also been discussed.  相似文献   
4.
A new lateral MOS-gated thyristor, called the Base-Current-Controlled Thyristor, is described. This device is designed so that most holes at the on-stage reach the P base through the floating P+ region adjacent to the P base and the on-state MOSFET. At the turn-off stage, the interruption of the hole current to the P base due to switching off the above MOSFET occurs simultaneously with the conventional turn-off operation. The concept of this device is verified experimentally by using the fabricated lateral device with the external MOSFET. This device exhibits a better trade-off relation between the on-state voltage and the turn-off time compared uith the conventional MOS-gated thyristor  相似文献   
5.
A transceiver PIC consisting of a DFB-LD, a receiver PD and a Y-shaped branch waveguides is realized by in-plane bandgap energy controlled selective MOVPE. Both active and passive core layers are formed in one step selective growth, and complicated fabrication procedure is no longer required. More than 1 mW fiber coupled power and 7 GHz receiver bandwidth are obtained. The modulation and detection operations at 500 Mb/s are successfully demonstrated.  相似文献   
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Three phase partitioning (TPP) uses t-butanol and ammonium sulfate to precipitate enzymes and proteins from aqueous solutions. The method is useful both upstream with crude samples and downstream where a scaleable simple step is needed. About 25 enzymes and proteins have been isolated by various laboratories using TPP-t-butanol. The relation of t-butanol used in TPP, with n-butanol used as an extraction agent from Morton's work, is reviewed. Some t-butanol appears bound to TPP-precipitated proteins which are actually protein-t-butanol coprecipitates. They float above denser aqueous salts because bound t-butanol increases their buoyancy, similar to the behavior of many lipoproteins. On redissolving TPP-precipitated enzymes, total and specific activities usually are regained and sometimes increased. Sulfate ion-in large concentrations-likely exerts itself through its kosmotropic action as in conventional salting out. t-Butanol likewise appears to be a kosmotrope and crowding agent at room temperature or above, whereas C1 and C2 cosolvents (e.g., ethanol) do not so behave except at near or below zero temperatures. However, kosmotropy is not the entire origin of TPP, nor probably of conventional salting out. Electrostatic forces, capacity to force protein conformation tightening and protein hydration shifts, also contribute. Electrostatic forces, and the tendency for salt ions to bind and tighten protein molecule conformation, are indicated by the sharp pH dependency of both conventional salting out and TPP, around pH regions where proteins undergo conformation changes. Sulfate anion is densely-perhaps extraordinarily-hydrated, adding much to its effective size, and therefore it has a tendency to crowd or exclude proteins, when sulfate concentrations are in the 0.5 to 3 M range.  相似文献   
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We recorded all-night polysomnograms of four schizophrenic patients with neuroleptic-induced akathisia (NIA) before and during treatment with clonazepam. Also, four non-akathitic schizophrenic patients were recorded all-night polysomnograms as control subjects. Daily treatment with 1.5 to 3 mg clonazepam improved subjective complaints of all the 4 patients with NIA. Three of 4 patients with NIA exhibited periodic limb movements (PLM) on bilateral legs, but none of 4 control subjects showed PLM. Total number of PLM and PLM per hour decreased during clonazepam treatment. Moreover, mean inter-movement intervals of PLM of 3 patients were prolonged on bilateral legs. NIA might change its feature as PLM during night sleep.  相似文献   
10.
The temperature dependence of luminescence from a long-lasting phosphor (LLP), SrAl2O4 : Eu2+,Dy3+, exposed to ionizing radiation has been measured to understand the LLP luminescence mechanism. Evaluation of the decay constants of the LLP exposed to -, β- or γ-rays at temperatures from 200 to 390 K showed that the decay constant is divided into four components ranging from 10−4 to 10−1 s−1 with activation energies of 0.02–0.35 eV.

Total luminous intensity from the LLP with changing irradiation temperature has its maximum value around the room temperature. Irradiation at elevated temperature (390 K) has the total luminescence pattern with monotonous decrease as temperature rises. As a result of evaluating the temperature dependence of luminescence, the luminescence mechanism is considered as follows:

 

Author Keywords: Radiation detection; Long-lasting phosphor; Luminescence; Temperature dependence; Fade-out effect  相似文献   

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