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We report on our study of SN 2022xxf during the first four months of its evolution. The light curves (LCs) display two humps at similar maximum brightness separated by 75d, unprecedented for a broad-lined Type Ic supernova (SN IcBL). SN~2022xxf is the most nearby SN IcBL to date (in NGC~3705, $z = 0.0037$, 20 Mpc). Optical and NIR photometry and spectroscopy are used to identify the energy source powering the LC. Nearly 50 epochs of high S/N-ratio spectroscopy were obtained within 130d, comprising an unparalleled dataset for a SN IcBL, and one of the best-sampled SN datasets to date. The global spectral appearance and evolution of SN~2022xxf points to typical SN Ic/IcBL, with broad features (up to $\sim14000$ km~s$^{-1}$) and a gradual transition from the photospheric to the nebular phase. However, narrow emission lines (corresponding to $\sim1000-2500$ km~s$^{-1}$) are present from the time of the second rise, suggesting slower-moving circumstellar material (CSM). These lines are subtle, but some are readily noticeable at late times such as in Mg~I $\lambda$5170 and [O~I] $\lambda$5577. Unusually, the near-infrared spectra show narrow line peaks, especially among features formed by ions of O and Mg. We infer the presence of CSM that is free of H and He. We propose that the radiative energy from the ejecta-CSM interaction is a plausible explanation for the second LC hump. This interaction scenario is supported by the color evolution, which progresses to the blue as the light curve evolves along the second hump, and the slow second rise and subsequent rapid LC drop. SN~2022xxf may be related to an emerging number of CSM-interacting SNe Ic, which show slow, peculiar LCs, blue colors, and subtle CSM interaction lines. The progenitor stars of these SNe likely experienced an episode of mass loss shortly prior to explosion consisting of H/He-free material., Comment: Submitted. SN~2022xxf is still bright ($\sim18$ mag), has good sky visibility in the next few months, and shows a flattening in the current LC. The community is urged to join the monitoring effort in all wavelengths in order to understand this extraordinary object and its pre-SN behavior

第21回宇宙科学シンポジウム (2021年1月6日-7日. オンライン開催), 21st Space Science Symposium (January 6-7, 2021. Online Meeting), 資料番号: SA6000163146, レポート番号: Pa.03

Purpose: The aims of this study were to prepare a 0.1% Miconazole (MCZ) eye-drop solution and to evaluate the stability and physical properties of the preparation.Methods: For 0.1% MCZ eye-drops (containing 1mg/mL MCZ), a Normal Saline Solution (NSS)-added system in which MCZ injection was diluted with NSS, an L-lactate Ringer’s Solution (LRS)-added system diluted with LRS and NSS, and a lactic acid-added system diluted with lactic acid and NSS were aseptically prepared. The storage conditions for the NSS-added system were dark condition (25°C, RH84%), cold condition (4°C), and severe condition (40°C, RH82%). The LRS-added system and the lactic acid-added system were stored only at 4°C.Results: MCZ eye-drops diluted with physiological saline showed a reduction in MCZ content to approximately 90% after 2 weeks of storage at 4°C, and precipitates were confirmed in the eye-drop solution. The pH was maintained at 4.8 and the osmolality at 280mOsmol/kg. When lactic acid was added at concentrations of 1% and 0.5%, MCZ precipitation was confirmed after storage for 4 weeks, and the MCZ content decreased to ≤ 90%, with a pH of approximately 3.0-3.5. However, when 0.3% lactic acid was added, the MCZ content was maintained after 4 weeks, but the pH dropped to about 3.9.Conclusion: These results suggest that storing MCZ eye-drops at 4°C for 7 days is reasonable. In addition, the storage period could be extended up to 4 weeks under conditions of 25°C, RH84% or 40°C, RH82%. MCZ eye-drop solution containing 0.3% lactic acid can remain stable for 2 weeks when stored at 4°C., This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

Remotely operable compact instruments for measuring atmospheric CO2 and CH4 column densities were developed in two independent systems: one utilizing a grating-based desktop optical spectrum analyzer (OSA) with a resolution enough to resolve rotational lines of CO2 and CH4 in the regions of 1565–1585 and 1674–1682 nm, respectively; the other is an application of an optical fiber Fabry-Perot interferometer (FFPI) to obtain the CO2 column density. Direct sunlight was collimated via a small telescope installed on a portable sun tracker and then transmitted through an optical fiber into the OSA or the FFPI for optical analysis. The near infrared spectra of the OSA were retrieved by a least squares spectral fitting algorithm. The CO2 and CH4 column densities deduced were in excellent agreement with those measured by a Fourier transform spectrometer with high resolution. The rovibronic lines in the wavelength region of 1570–1575 nm were analyzed by the FFPI. The I0 and I values in the Beer-Lambert law equation to obtain CO2 column density were deduced by modulating temperature of the FFPI, which offered column CO2 with the statistical error less than 0.2% for six hours measurement.

The use of an electrochemical detector (ECD) and core-shell columns as a new quantitative method for the analysis of α-, β-, and γ-cyclodextrin(αCD, βCD, and γCD, respectively) was investigated, and simple quantitative methods and appropriate measurement conditions were developed. The retention times of αCD, βCD, and γCD were determined to be 6.5, 12.9, and 10.4 min, respectively, when measured using an ECD, a 50°C column temperature, 0.5 mL/ min flow rate, 20 µL injection volume, 0.3 mol/L NaOH/0.3 mol/L CH3 COONa=1/1 mobile phase, and an S-40/60=St (styrene)/DVB (divinylbenzene)-5TMA (trimethylamine) core-shell column. The calibration curves of αCD, βCD, and γCD demonstrated good linearity (R2 >0.998). The repeatability, precision, and accuracy were acceptable (relative standard deviation