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301.
Tsuyoshi Arakawa Toshiharu Takata Gin-Ya Adachi Jiro Shiokawa 《Journal of luminescence》1979,20(3):325-327
The luminescent properties of Eu ion incorporated in a Y-type zeolite have been studied. The emission spectrum at room temperature is due to the transition between 5D and 7F levels of the Eu3+ ion. However the emission band for Eu3+ decreased as this compound was degassed at above 300°C and the band emission, peaked at 445 nm, appeared. This band emission is associated with Eu2+ 5d to 4f transition. 相似文献
302.
Some physicochemical properties of glassy indomethacin 总被引:2,自引:0,他引:2
303.
Guoyang Guan Shuhei Fukuoka Satoshi Yamashita Takashi Yamamoto Hiromi Taniguchi Yasuhiro Nakazawa 《Journal of Thermal Analysis and Calorimetry》2013,113(3):1197-1201
Thermodynamic investigation using the relaxation calorimetry technique and the microchip calorimetry technique is performed to clarify low-temperature behaviors of a radical cation salt consisting of a donor molecule of bispropylenedithiotetrathiafulvalene (BPDT-TTF) and a linear anion of ${{\text{ICl}}_{2}^{-}}$ ICl 2 ? . This compound has a layered structure similar to numerous BEDT-TTF compounds. The donor molecules form a dimerized arrangement in the layer. Temperature dependence of heat capacity obtained by the relaxation technique shows a broad hump structure around 20–25 K corresponding to the temperature where the magnetic susceptibility shows a drastic decrease due to the formation of the singlet spin state. The microchip calorimetry technique detected a step-like anomaly around 23 K in the temperature dependence of C p T ?1 of which entropy is evaluated as only few % of Rln2 corresponding to the full entropy of localized π-electrons located on each dimer unit. The negligibly small T-linear term in the low-temperature heat capacity and absence of magnetic fields dependence below 3.2 K predict opening of rigid gap structure in the spin excitations, which is consistent with a spin-singlet formation due to the formation of spin-Peierls type ordering or charge ordering state. 相似文献
304.
Shuhei Fukuoka Yuki Horie Satoshi Yamashita Yasuhiro Nakazawa 《Journal of Thermal Analysis and Calorimetry》2013,113(3):1303-1308
We report on construction of a new low temperature heat capacity measurement system. This system was designed for performing thermodynamic investigation by thermal relaxation technique for small amount of samples at extremely low temperature region between 70 mK and 10 K. Two different calorimetry cells for this system were designed. One is a usual-type calorimetry cell consisting of tiny chip-type thermometer and strain gauge heater. The size of the sample stage has been reduced for measuring small samples. The other is designed for performing heat capacity measurements under magnetic fields of which magnitude and direction are accurately controlled. The calorimetry cells with heat capacity measurement unit can be mounted on a handy top-loading type dilution refrigerator of which outer diameter including the adiabatic space is 27 mm. We discuss basic performance and specification of the constructed cells and low temperature heat capacity data of an organic charge transfer salt obtained by this system. 相似文献
305.
Abstract
Vortex levitation can achieve non-contact handling by blowing air into a vortex cup through a tangential nozzle to generate a swirling flow. In this paper, we focused on the relationship between the sucking pressure and the flow dynamics when gap distance from the cup to a work piece changes. Then simultaneous measurement of a pressure and a flow field in the cup was performed. As a result, the mean pressure changes and the pressure fluctuation inside the cup enhances with increasing gap height. Especially, periodic pressure perturbation is observed with wide gap height and it synchronizes with an eccentric rotation of the swirling flow. It is also found that the rotation axis of swirling flow steadily inclines against the central axis of the cup for appropriate gap height. 相似文献306.
Optical Review - To visualize the microscopic internal structure of cells, some conventional methods exist in the literature, such as irradiating fluorescent substances with light that maintains... 相似文献
307.