Electrical measurements on fused quartz under shock compression

The resistivities of specimens of SiO_2 (fused quartz) singly and doubly shocked in the 10–45 and 27–90 GPa ranges, respectively, demonstrate a marked decrease from values of ∼10–0.1 Ω⋅m at a single‐shock pressure of ∼40 and a double‐shock pressure of ∼74 GPa. These states correspond to calculated shock temperatures of ∼3300 and ∼3600 K, respectively. At shock pressures below 36 GPa the measured resistivity versus calculated shock temperature agrees closely with ambient‐pressure and high‐temperature resistivity data. This suggests that the ionic conduction mechanisms inferred to control electrical properties at ambient pressure also act under shock‐induced high temperatures in quartz and the presumed high‐pressure phase, stishovite into which fused quartz appears to transform above 20 GPa. At 36–40 GPa the rapid decrease in resistivity by a factor of 10^2 suggests a further transformation to an unknown phase which may correspond to the onset of melting. The existing pressure‐density Hugoniot data do not demonstrate any anomalous density change associated with this phase change

Shock-induced radiation spectra of fused quartz

An optical multichannel analyzer is applied to observe shock-induced radiation spectra of fused quartz in the 23–31 GPa shock-pressure range. Characteristics of sample-driver interface strongly influence both intensity and profile of the observed spectra. Brightness and color temperature are determined by an integration of spectral radiance and a fit to the greybody radiation spectrum, respectively. The resultant brightness and color temperature are lower and considerably higher than those estimated by the theoretical calculation, respectively. Some broad but strong line spectra are, however, superimposed onto the continuous greybody radiation spectrum even though the influences of the interface are reduced as much as possible. The line spectra are probably caused by electroluminescence and/or triboluminescence

Shock compression of diamond crystal

Two shock wave experiments employing inclined mirrors have been carried out to determine the Hugoniot elastic limit (HEL), final shock state at 191 and 217 GPa, and the post-shock state of diamond crystal, which is shock-compressed along the intermediate direction between the and crystallographic axes. The HEL wave has a velocity of 19.9 ± 0.3 mm/µsec and an amplitude of 63 ± 28 GPa. An alternate interpretation of the inclined wedge mirror streak record suggests a ramp precursor wave and then another HEL value. The maximum post-shock density achieved upon release from the ∼200 GPa shock state is ∼3.95 Mg/m³, which compares to the initial density 3.52 Mg/m³. This result suggests an elastic unloading effect or shock-induced transition to a denser (possibly metallic) phase

Relative Amounts of Keratin 17 Are Higher Than Those of Keratin 16 in Hair-Follicle-Derived Tumors in Comparison with Nonfollicular Epithelial Skin Tumors

Specimens of trichilemmal cyst, malignant trichilemmoma, keratoacanthoma, and epidermal cyst were examined to characterize keratin peptides in hair- follicle-derived tumors, Keratins were extracted front the specimens and analyzed by two-dimensional gel electrophoresis and densitometry, the re- sults were then compared with those for normal epidermis, the outer root sheath of hair follicles, psoriatic epidermis, and various nonfollicular cutaneous epithelial tumors. The specific nonfolilcular tumors examined were squamous cell carcinoma, Bowen disease, actinic keratosis, eccrine porocarcinoma, and sebaceous carcinoma. Immunohistochemistry also was performed with a few anti-keratin monoclonal antibodies. As a general rule, K6 and K16 were expressed in hyperproliferative conditions, such as epidermal tumors, and K17 was coexpressed in the same lesions, The ratio of K16 to K17 in many epithelial skin tumors has been unclear until now. K17 content exceeded K16 content in most follicular tumors, whereas in almost all the nonfollicular tumors and the psoriatic epidermis, K17 levels were less than or about equal to K16 levels. There was a significant difference in the ratio of K16 to K17 between follicular and nonfollicular skin tumors. These results indicate that alterations in the content of these keratins may be associated with follicular differentiation

Effects of a nurse-occupational therapist meeting on function and motivation in hospitalized elderly patients: A pilot randomized control trial

学位記番号：保博甲15

The Effect of Side Traps on Ballistic Transistor in Kondo Regime

The effect of side-traps on conductance is calculated in the range of slave-boson mean field theory, especially when there are electrodes on both sides of the conductor. This corresponds to an investigation of transport properties in future ballistic transistors. An intrinsic dip as a result of the interference effect (Fano-Kondo effect) is expected to be observed as one of interesting interplays between physics and engineering devices.Comment: 3 pages, 5 figures. 2006 International Conference on Solid State Devices and Materials (SSDM2006), Sept. 12-15, 2006, Yokohama, Japa