Herein, a facile bottom–up approach for producing nitrogen-doped carbon quantum dots (N-CQDs) was carried out by the hydrothermal treatment of microcrystalline cellulose, in the presence of different nitrogen sources (blank/urea/ammonia water/ethanediamine(EDA)/Hexamethylenetetramine). The result showed that the fluorescence intensity and quantum yields (QYs) of N-CQDs with different nitrogen sources are all higher than that without nitrogen source. Compared with the other three nitrogen sources, N-CQDs prepared by EDA not only have the highest fluorescence intensity but also the largest QYs of 51.39%. Therefore, EDA was chosen as the nitrogen source to prepare N-CQDs. The obtained N-CQDs are uniform spherical particles with a diameter of 2.76 nm. The N-CQDs also exhibit excitation-dependent and long-wave emission properties. The emission range of N-CQDs is 470–540 nm. Moreover, N-CQDs as fluorescent agents successfully acted on purple LEDs (λem = 365 nm) to achieve white LEDs light emission. At the same time, a fluorescent thin layer chromatography plate was successfully prepared using N-CQDs, silica gel G and Sodium carboxymethylcellulose as raw materials. The separation trajectory of mixed sample of Sudan red III and kerosene on the fluorescent TLC plate is obviously clearer than that of the TLC plate.

We introduce a code called tlc s05, to fit sparsely sampled JHK band Cepheid light curve data with template light curves to derive the mean magnitude. A brief description of the code is provided here. We tested the performance of the code in deriving the mean JHK band magnitudes using simulations, and we found that it is better to observe more than four evenly spaced data points per light curve, which permits tlc s05 to derive accurate mean magnitudes for Cepheid JHK band light curves.

This study analyzes the structure types of salmon oil to evaluate the purity of salmon oil products based on the 38 different types of imported salmon oil products distributed in the Republic of Korea. The major types of omega-3 foods in the salmon oil are ethyl ester (EE) and triglyceride (TG). If the salmon oil contained potential contaminants and was processed in order to remove it, EE type omega-3 fatty acids are found in concentration. This provides a good guide in assessing if products were made with EE type ingredients or re-esterified contaminated materials. The results of the FT-IR analysis showed significant difference in the C=O, C-O band positions in TG and EE. There were 19 TG type products and 19 EE type products. The analysis of carbon isotope ratio was performed on the types of TG and EE. There were different properties in the 19 TG type products. In one product, the carbon isotope ratio was －25.15 and the other 18 products showed －22.15～－23.96. The carbon isotope ratio of all 19 EE type products showed －21.91～－23.74. The results of the TLC analysis showed similar results with FR-IR. The re-esterified TG form was not detected in the TG type products, confirming that the TG type products contained natural salmon oil. This study aimed to provide the basic material in classifying the types of natural salmon oil and re-esterified salmon oil, by analyzing the pattern and proportion of FT-IR spectrum, carbon isotope ratio, and TLC.

가열우지중 콜레스테롤 산화안정성을 연구하기 위하여 130, 150 및 18 가열온도에서 일정시간 가열하였을 때 생성되는 각종 콜레스테롤 산화생성물을 TLC에 의하여 분리.확인하고, 지방산 조성의 변화를 측정하였다. 지방산 조성은 가열시간이 경과함에 따라 linoleic과 linolenic acid등의 불포화 지방산은 약간씩 감소한 반면 포화지방산의 함량은 다소 증가하는 경향이었고, 이러한 변화는 가열온도가 높을수록 심하였다. 추출한 비비누화물의