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Chinese Journal of Chemical Engineering 2019年第10期27卷 2407-2417页

作者： Kangning Xiong Yun Chen shuai shen Department of Chemistry and Chemical Engineering South China University of TechnologyGuangzhou 510640China

The supercritical carbon dioxide extraction was applied to obtain essential oil from Pogostemon cablin in this *** of extraction parameters including temperature,pressure,extraction time and particle size on extraction yield was investigated,and the response surface methodology with a Box–Behnken Design was used to achieve the optimized extraction *** maximum yield of essential oil was 2.4356%under the conditions of extraction temperature 47°C,pressure 24.5 MPa and extraction time 119 ***,based on the Brunauer–Emmett–Teller theory of adsorption,a mathematical modeling was performed to correlate the measured *** model shows a function relationship between extraction yield and time by a simple equation with three significantly adjustable *** model parameters have been optimized through simulated annealing *** predicted data from the mathematical model show a good agreement with the experimental data of the different extraction parameters.

关键词： Supercritical carbon dioxide extraction Pogostemon cablin Response surface methodology Mathematical modeling Simulated annealing algorithm

Measurements and correlation of liquid–liquid equilibrium data for the ternary(methyl tert-butyl ketone + o, m, p-benzenediol + water)system at(333.2, 343.2 and 353.2) K

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Chinese Journal of Chemical Engineering 2019年第4期27卷 905-911页

作者： Kangning Xiong shuai shen Youchang Wang Yun Chen State Key Laboratory of Pulp and Paper Engineering Department of Chemistry and Chemical Engineering South China University of Technology Guangzhou 510640 China Department of Chemical & Biomolecular Engineering North Carolina State University Raleigh NC 27695 USA

In this work, liquid–liquid equilibria(LLE) data for the ternary system methyl tert-butyl ketone(MTBK)+ o, m,p-benzenediol + water were investigated at 333.2 K, 343.2 K and 353.2 K under 101.3 kPa. The performance of MTBK to extract o, m, p-benzenediol from wastewaters was estimated by partition coefficients and separation factors. The Hand and Bachman equations were both applied to check the reliability of the experimental LLE data. Furthermore, the Non-Random Two-Liquid(NRTL) and Universal Quasi Chemical(UNIQUAC) models were applied to correlate the measured LLE data. The results showed a good agreement with the determined ternary LLE data with the root-mean-square error(RMSE) values below 0.71%. MTBK was proved to be a promising extracting agent in extracting benzenediols from effluents.

关键词： Liquid–liquid equilibrium Methyl tert-butyl ketone Benzenediol NRTL model UNIQUAC model

Salt effect on the liquid–liquid equilibrium of the ternary (water + phenol + methyl isobutyl ketone) system: Experimental data and correlation

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Chinese Journal of Chemical Engineering 2019年第1期27卷 168-173页

作者： Yun Chen Kangning Xiong shuai shen Huimin Wang Shaoming Zhou Libo Li Department of Chemistry and Chemical Engineering South China University of Technology State Key Laboratory of Pulp and Paper Engineering South China University of Technology

The effects of NaCl, KCl and Na_2SO_4 on the liquid–liquid equilibrium(LLE) data for the ternary system, water+ phenol + methyl isobutyl ketone, were determined at 0.101 MPa and 333.15 K and 343.15 *** nonrandom two-liquid(NRTL) model was used to correlate the experimental data and to yield corresponding binary interaction parameters for these salt containing *** Hand and Othmer–Tobias equations were used to confirm the dependability of the determined LLE data in this *** coefficient and selectivity were used to evaluate the extraction performance of methyl isobutyl ketone with the existence of *** magnitude of salt effect on the water + phenol + methyl isobutyl ketone(MIBK) system is in the following order: Na_2SO_4>NaCl>KCl.

关键词： Liquid-liquid equilibrium Methyl isobutyl ketone Salt effect Phenol

Treatment of primary tracheal schwannoma with endoscopic resection:A case report

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World Journal of Clinical Cases 2022年第28期10卷 10279-10285页

作者： Yong-shuai shen Xiang-Dong Tian Yi Pan Hua Li Department of Endoscopy Tianjin Cancer Hospital Airport HospitalTianjin 300000China Department of Endoscopy Tianjin Medical University Cancer Institute and HospitalTianjin 300060China Department of Pathology Tianjin Medical University Cancer Institute and HospitalNational Clinical Research Center for CancerKey Laboratory of Cancer Prevention and TherapyTianjin’s Clinical Research Center for CancerTianjin 300060China Department of Endoscopy Tianjin Medical University Cancer Institute and HospitalNational Clinical Research Center for CancerKey Laboratory of Cancer Prevention and TherapyTianjin’s Clinical Research Center for CancerTianjin 300060China

BACKGROUND Schwannoma is a benign tumor originating from the peripheral nerve *** clinical symptoms of tracheal schwannoma depend on the location of the tumor,and the most common clinical symptoms are cough and *** most effective treatment for benign tumors is complete resection of the primary lesion at an early *** experience has demonstrated that primary tracheal schwannoma can be safely excised with a high-frequency electric knife in a minimally invasive *** SUMMARY We report a 61-year-old asymptomatic woman who underwent chest computed tomography(CT),which accidentally found an intraluminal tracheal mass without enlarged lymph ***,the patient underwent bronchoscopy,which found that the tracheal mass originated from the left wall of the upper trachea,was less than 1.5 cm in size,immovable,smooth and 4 cm away from the vocal cord,resulting in partial upper respiratory tract *** was performed using an endoscopic resection for en bloc removal of the tracheal *** diagnosis was primary tracheal schwannoma.A follow-up was performed after endoscopic surgery,and bronchoscopy and thoracic CT were used to monitor whether there was a *** present,there is no evidence of recurrence,and the patient had a good quality of *** resection may be effective and safe in the treatment of primary tracheal *** Primary tracheal schwannoma is a very rare benign *** this case,we cured it by complete endoscopic resection.

关键词： Schwannoma Tracheal tumor Endoscopic therapy High-frequency electric knife En bloc Case report

Distribution and Source of Nitrate in Groundwater in the hilly-Plain Transition Area of Jianghan Plain Using Dual N and O Isotopes of Nitrate

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Journal of Earth Science 2023年

作者： Kewen Luo Teng Ma shuai shen School of Environmental Studies China University of Geosciences State Environmental Protection Key Laboratory of Source Apportionment and Control of Aquatic Pollution Hubei Key Laboratory of Yangtze Catchment Environmental Aquatic Science China University of Geosciences

Nitrogen contamination of groundwater in the Jianghan Plain (JHP) in the middle reach‐es of the Yangtze River is widespread,but the sources and fate of nitrate (NO3-) in the transitional area between plains and hills are poorly *** paper characterized the distribution,sources and transformation processes of NO3-in groundwater in the hilly-plain transition area of JHP through hy‐drogeochemistry and dual isotopes (δ15N and δ18O-NO3-).The hydrogeochemical results showed that the NO3-in the plain and hilly areas is heterogeneous and controlled by *** plain to hilly ar‐eas in summer,NO3-in groundwater has a general trend of decreasing with the direction of groundwa‐ter *** groundwater in the plain area is strongly affected by anthropogenic activities,and the NO3-in the multi-level aquifer gradually decreases with increasing *** in redox conditions caused by river erosion may be responsible for higher NO3-in groundwater along the eroded *** isotopic results showed that NO3-in the hilly area mainly comes from soil organic nitrogen,which is a natural ***,groundwater NO3-in the plain area is strongly affected by livestock manure and domestic sewage,which may be owing to the high density of residents and the impact of anthropo‐genic activities.

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Two birds with one stone:Construction of bifunctional-POSS hybridized boron-silicon ceramicized phenolic composites and its ablation behavior

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Journal of Materials Science & Technology 2023年第10期141卷 199-208页

作者： Zhaoqi Niu Yi Xin Luyao Wang shuai shen Xiaoyan Ma Beixi Chen Chengzhi Wang Fang Chen Chengshuang Zhang Xiao Hou Shaanxi Key Laboratory of Macromolecular Science and Technology Northwestern Polytechnical UniversityXi’an 710072China Xi’an Aerospace Composites Research Institute Xi’an 710025China China Aerospace Science and Technology Corporation China

To further enhance the ablation resistance properties of thermosetting phenolic resin matrix composites,in this work,bifunctional alkalic heptaphenyltrisilanol sodium salt polyhedral oligomeric silsesquioxane was utilized to catalyze the synthesis of boron phenolic resin and provide silicon source to obtain boron-silicon hybrid phenolic resin(BPOSSPR)with excellent ablative *** possesses a low cur-ing activation energy(101.4 kJ/mol)and excellent thermal properties(initial decomposition temperature was 453.0℃and char yield at 1000℃was 72.7%).The mechanical and thermal insulation properties of carbon fiber reinforced BPOSSPR composites(CF/BPOSSPR)and high silica fiber reinforced BPOSSPR composites(HSF/BPOSSPR)are significantly *** linear ablation rate and mass ablation rate of CF/BPOSSPR are as low as 0.003 mm/s and 0.0354 g/s;those of HSF/BPOSSPR are 0.119 mm/s and 0.0264 g/*** ablation-resistance mechanism of BPOSSPR composites is mainly due to the formation of ceramic thermal barrier layers under high temperature conditions,such as B_(2)O_(3),SiO_(2),borosilicate glass,SiC,which might play an effective role in protecting against heat flow *** a result of these ex-cellent properties,the innovative heat shielding BPOSSPR composites could offer the ability to tolerate harsher environment in future aerospace applications.

关键词： Ceramicized composites High-temperature properties Ablation behavior Bifunctional-POSS catalyst

A review of research on the chemical constituents and pharmacological effects of Elephantopus tomentosus L.

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Asian Journal of Traditional Medicines 2023年第1期18卷 15-24页

作者： shuai shen Ming Bai Shaojiang Song Department of Natural Products Chemistry Key Laboratory of Structure-Based Drug Design and DiscoveryMinistry of EducationSchool of Traditional Chinese Materia MedicaShenyang Pharmaceutical UniversityShenyang 110016PR China

Elephantopus tomentosus,belonging to the genus Elephantopus,is widely distributed in the coastal areas of southern China and tropical regions,used locally as traditional folk *** phytochemistry studies on Elephantopus tomentosus led to the isolation of sesquiterpenoids,triterpenoids,flavonoids and other *** has shown that these compounds possess multiple biological activities,which have attracted great attention of researchers *** study reviews the chemical constituents and biological activities of the Elephantopus tomentosus in order to better explore and utilize Elephantopus tomentosus.

关键词： Elephantopus tomentosus chemical composition pharmacological activities sesquiterpenoids

Chemical components from Crotalaria pallida Ait. and their antioxidant activities

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Asian Journal of Traditional Medicines 2022年第1期17卷 1-8页

Nine compounds were isolated from the 95%ethanol extract of the dried seeds of Crotalaria *** structures of all compounds were identified through the analysis of spectral *** compounds were isolated for the first time from Crotalaria *** 1-5 were evaluated for their antioxidant abilities by ABTS,DPPH and FRAP *** showed that compounds 1-5 had moderate antioxidant activities。

关键词： Crotalaria pallida Ait separation and purification structural analysis antioxidant activities

基于峰宽修正的玻璃药瓶内氧气残留浓度的检测研究

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红外与毫米波学报 2022年第5期41卷 879-887页

作者：申帅贺建军中南大学自动化学院湖南长沙410083

玻璃药瓶中的氧气残留对瓶中药品的无菌特性造成了严重的威胁。采用波长调制光谱(Wavelength Modulated Spectrum,WMS)技术解调得到的二次谐波信号峰高值作为氧浓度反演的基础。然而,在用二次谐波信号测量气体浓度时,由于调制深度的变... 详细信息

玻璃药瓶中的氧气残留对瓶中药品的无菌特性造成了严重的威胁。采用波长调制光谱(Wavelength Modulated Spectrum,WMS)技术解调得到的二次谐波信号峰高值作为氧浓度反演的基础。然而,在用二次谐波信号测量气体浓度时,由于调制深度的变化会导致二次谐波峰值的变化,这通常会给系统带来误差,进而降低浓度的反演精度。而调制深度受调制电流波动、温度和压强变化等因素的影响不能直接计算获得进而修正。针对这一问题,本文成功地将调制深度与二次谐波峰高的关系转换为二次谐波峰宽和峰高的关系。然后,利用峰宽校正后的谐波峰高对气体浓度进行反演。初步实验表明,利用峰宽校正后的谐波峰高对瓶内气体浓度进行预测的准确性提高了2.1%,且系统的整体鲁棒性也得以提升。本文提出的校正方法不需要系统参数信息与气体成分信息,可以直接从谐波信号本身出发对调制深度进行校正,十分适合于工业现场的在线氧气浓度预测。

关键词：波长调制光谱(WMS) 氧气残留检测调制深度峰宽峰高

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质子在碳化硅中不同深度的非电离能量损失

物理学报 2018年第18期67卷 36-43页

作者：申帅帅贺朝会李永宏西安交通大学核科学与技术学院西安710049

利用蒙特卡罗方法,应用Geant4程序,模拟计算了1—500 MeV质子在碳化硅材料中的非电离能量损失,并研究了不同种类的初级反冲原子对非电离能量损失的贡献.模拟结果表明:在相同质子辐照下,碳化硅材料中的非电离能量损失要比硅、镓等半导体... 详细信息

利用蒙特卡罗方法,应用Geant4程序,模拟计算了1—500 MeV质子在碳化硅材料中的非电离能量损失,并研究了不同种类的初级反冲原子对非电离能量损失的贡献.模拟结果表明:在相同质子辐照下,碳化硅材料中的非电离能量损失要比硅、镓等半导体材料更小,说明碳化硅器件的稳定性更好,抗位移损伤能力更强;当靶材料足够厚时,在不同能量质子辐照下,材料损伤最严重的区域会随着质子入射能量的增加从质子射程末端逐渐前移到材料表面;不同种类的初级反冲原子对非电离能量损失的贡献表明,在低能质子辐照下,28Si和^(12)C是位移损伤的主要原因,而随着质子能量的增加,通过核反应等过程产生的次级离子迅速增多,并对材料浅层造成严重的位移损伤.

关键词：碳化硅 Geant4 非电离能损位移损伤