INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
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2018
·
IF 3.141
Yong-Sheng Xu,Rui-Xiong Zhao,Kang-Kang Pei,Guo-Liang Zhang,Qing Xia,Feng-Bao Zhang
An optimal design of the neutralization process in 1,5-dihydroxynaphthalene production was proposed and discussed. In the new strategy, instead of sodium chloride, sodium sulfate was used in the salting-out process to overcome the drawbacks of the traditional strategy. Then the precipitated mixtures, mainly naphthalene-1,5-disulfonic acid (1,5-H2NDS) and sodium sulfate, were neutralized to obtain naphthalene-1,5-disulfonic acid disodium (1,5-Na2NDS) and sulfuric acid. By adjusting the concentrations of sulfuric acid solutions to 0.3 and 0.5 mass fractions, 1,5-Na2NDS and 1,5-H2NDS were precipitated out, respectively. The yields of both 1,5-H2NDS and 1,5-Na2NDS reached 0.98. 1,5-Na2NDS was sent to the alkali fusion process, while 1,5-H2NDS was reused in the neutralization. In neutralization, the mole ratio (1,5-H2NDS to sodium sulfate) was chosen as 2.5 and the reaction temperature was 353 K. In order to determine the separation conditions, the solubilities of 1,5-H2NDS·2H2O and 1,5-Na2NDS·H2O in aqueous sulfuric acid solutions were measured over the temperature range from 277 to 337 K at atmospheric pressure by a dynamic method. The new strategy is particularly instructive for the industrial production of 1,5-dihydroxynaphthalene.
研究领域:
化学工程
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工业化学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY A-CHEMISTRY
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2020
·
IF 3.306
Yuanming Li,Yaxiong Wei,Xiaoguo Zhou
Two new metal-free photosensitizers of Bodipy-carbazole derivatives, Phenyl-Bodipy-Carbazole (BC) and Carbazole-Bodipy-Carbazole (CBC), were synthesized. The transient absorption spectroscopy and the density functional theory calculations verify that the triplet Bodipy unit is produced in the dyads via an intramolecular charge transfer in the Franck-Condon excitation. Moreover, an apparent dependence on the solvent polarity was observed for these triplet states lifetimes, e.g. 9.6 and 118.2 μs in cyclohexane , while, 204.7 and 464.7 μs in dichloroethane for BC and CBC, respectively, as well as the triplet state quantum yields. With the increase of solvent polarity, the prolonged lifetime and the decreased quantum yield of the triplet BC and CBC convince us the charge-transfer mechanism for ISC process. In addition, the photo-oxidation rate constants of 1,5-dihydroxynaphthalene with these triplet photosensitizers are determined to be 1.11 × 10 −3 min -1 and 2.54 × 10 −3 min -1 for BC and CBC, respectively.
研究领域:
有机化学
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光化学
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材料科学
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DOI
高影响因子
Pharmaceutics
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2022
·Vol. 14
·期 11
·2478
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IF 6.525
Yihua Jiang,Yinxiang Cheng,Mengyuan Xia,Bingrui Zhang,Qiaoce Ding,Liye Lu,Jian-Rong Wang,Xuefeng Mei
Dehydroepiandrosterone (DHEA) is an FDA-approved food supplement used as an assisted reproductive sex hormone. The bioavailability is severely limited by its poor solubility (23 µg/mL). Herein, we aimed to modulate its solubility through cocrystallization. Eight cocrystals of DHEA with pyrocatechol (CAT), hydroquinone (HQ), resorcinol (RES), phloroglucinol (PG), 1,5-dihydroxy naphthalene (DHN), p-hydroxybenzoic acid (PHBA), gallic acid (GA), and 5-hydroxyisophthalic acid (5HIPA) were designed and synthesized. Some basic characterization tools, including powder X-ray diffraction, thermogravimetric analysis, differential scanning calorimetry, and Fourier transform infrared spectroscopy, were also applied in our work for basic analyses of cocrystals. It is indicated that DHEA-GA exhibits its superiority in dissolution and pharmacokinetic behaviors. While the area under the curve values of DHEA-GA is improved at the ratio of 2.2, the corresponding bioavailability of DHEA is expected to be accordingly increased.Keywords:DHEA;cocrystallization;crystal structure;solubility;bioavailability
研究领域:
药学
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材料科学
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化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）