Solvent extraction is the process of separating aromatics from vacuum distillates for the production oflubricating base oils. In this study, the authors use dimethyl sulfoxide (DMSO) instead of furfural as solvent, in...Solvent extraction is the process of separating aromatics from vacuum distillates for the production oflubricating base oils. In this study, the authors use dimethyl sulfoxide (DMSO) instead of furfural as solvent, in light of itshigher selectivity, to obtain extracts with a high aromatic content for naphthenic lubricating base oils. We systematicallyinvestigated effects of the solvent-to-oil (S/O) ratio and extraction temperature on the yield of the extract, efficiency ofaromatic removal, and composition of the extracts and raffinates. The results showed that the aromatic content of extractsfor naphthenic oils could reach a high value of about 80%. The solvent maintained a high selectivity for aromatics fornaphthenic oils even under a high S/O ratio and a high extraction temperature. Moreover, the efficiency of aromatic removalfor naphthenic lubricating base oils could be enhanced by increasing either the S/O ratio or the extraction temperature,although these measures had limited effects in practice. Following this, we used the non-random two-liquid (NRTL) modelbased on the pseudo-component approach to simulate the liquid-liquid equilibrium of the system of DMSO + naphtheniclubricating base oils, and determined the parameters of binary interaction through regression based on the data on phaseequilibrium. The modeling results showed that the predicted yield, content of the solvent, and composition of the raffinatesand extracts were in good agreement with those obtained in the experiments. This validates the reliability of the model usedto represent the DMSO + naphthenic lubricating base oil system. Both the experimental data and the method of simulationreported here can help optimize the extraction of naphthenic lubricating base oils, and provide a better understanding of thecorresponding process.展开更多
目的探讨我国人眼结膜吸吮线虫病患者临床特征及流行病学特点。方法检索中国知网、中文科技期刊全文数据库、中国生物医学文献数据库、中国中医药文献数据库、万方数据库、PubMed和Web of Science等数据库,收集2011—2022年我国人眼结...目的探讨我国人眼结膜吸吮线虫病患者临床特征及流行病学特点。方法检索中国知网、中文科技期刊全文数据库、中国生物医学文献数据库、中国中医药文献数据库、万方数据库、PubMed和Web of Science等数据库,收集2011—2022年我国人眼结膜吸吮线虫病病例报告类文献,提取患者性别、年龄、临床症状、治疗、复发情况、发生地、发病时间、发病眼、发病部位、线虫数量、线虫性别及感染源等信息进行描述性统计分析。结果共纳入85篇文献,报道人眼结膜吸吮线虫病101例,男女性均有患病,其中男性57例(占56.44%)、女性44例(占43.56%);年龄3个月~85岁;主要临床表现包括异物感(56例·次,占22.49%)、眼痒(38例·次,占15.26%)、异常分泌物或分泌物增多(36例·次,占14.46%)、流泪(28例·次,占11.24%)和眼红(28例·次,占11.24%)等;临床体征以结膜充血(50例·次,占41.67%)最常见。患者主要(99/101,占98.02%)以眼科镊将虫体取出,再予以氧氟沙星、普拉洛芬等抗炎药进行治疗。在92例明确提及复发情况的病例中,90例(90/92,占97.83%)无复发、2例(2/92,占2.17%)出现复发。发病地区主要集中于湖北省、山东省、四川省、河北省和河南省(53例,占51.96%)等大陆性季风和亚热带季风气候区;发病月份主要集中于夏秋两季(均为27例,各占42.19%)。病例中35例(35/62,占56.45%)明确患者与犬接触。结论我国结膜吸吮线虫病病例主要分布于黄河和长江流域等大陆性季风和亚热带季风气候区,各年龄段、各性别人群均有患病,临床症状和体征均较复杂。预防结膜吸吮线虫病需注意个人卫生、减少与流行区犬的接触,同时还需在户外活动时加强个人防护。展开更多
基金the Natural Science Foundation of Xinjiang Uygur Autonomous Region(No.2022D01F37).
文摘Solvent extraction is the process of separating aromatics from vacuum distillates for the production oflubricating base oils. In this study, the authors use dimethyl sulfoxide (DMSO) instead of furfural as solvent, in light of itshigher selectivity, to obtain extracts with a high aromatic content for naphthenic lubricating base oils. We systematicallyinvestigated effects of the solvent-to-oil (S/O) ratio and extraction temperature on the yield of the extract, efficiency ofaromatic removal, and composition of the extracts and raffinates. The results showed that the aromatic content of extractsfor naphthenic oils could reach a high value of about 80%. The solvent maintained a high selectivity for aromatics fornaphthenic oils even under a high S/O ratio and a high extraction temperature. Moreover, the efficiency of aromatic removalfor naphthenic lubricating base oils could be enhanced by increasing either the S/O ratio or the extraction temperature,although these measures had limited effects in practice. Following this, we used the non-random two-liquid (NRTL) modelbased on the pseudo-component approach to simulate the liquid-liquid equilibrium of the system of DMSO + naphtheniclubricating base oils, and determined the parameters of binary interaction through regression based on the data on phaseequilibrium. The modeling results showed that the predicted yield, content of the solvent, and composition of the raffinatesand extracts were in good agreement with those obtained in the experiments. This validates the reliability of the model usedto represent the DMSO + naphthenic lubricating base oil system. Both the experimental data and the method of simulationreported here can help optimize the extraction of naphthenic lubricating base oils, and provide a better understanding of thecorresponding process.
文摘目的探讨我国人眼结膜吸吮线虫病患者临床特征及流行病学特点。方法检索中国知网、中文科技期刊全文数据库、中国生物医学文献数据库、中国中医药文献数据库、万方数据库、PubMed和Web of Science等数据库,收集2011—2022年我国人眼结膜吸吮线虫病病例报告类文献,提取患者性别、年龄、临床症状、治疗、复发情况、发生地、发病时间、发病眼、发病部位、线虫数量、线虫性别及感染源等信息进行描述性统计分析。结果共纳入85篇文献,报道人眼结膜吸吮线虫病101例,男女性均有患病,其中男性57例(占56.44%)、女性44例(占43.56%);年龄3个月~85岁;主要临床表现包括异物感(56例·次,占22.49%)、眼痒(38例·次,占15.26%)、异常分泌物或分泌物增多(36例·次,占14.46%)、流泪(28例·次,占11.24%)和眼红(28例·次,占11.24%)等;临床体征以结膜充血(50例·次,占41.67%)最常见。患者主要(99/101,占98.02%)以眼科镊将虫体取出,再予以氧氟沙星、普拉洛芬等抗炎药进行治疗。在92例明确提及复发情况的病例中,90例(90/92,占97.83%)无复发、2例(2/92,占2.17%)出现复发。发病地区主要集中于湖北省、山东省、四川省、河北省和河南省(53例,占51.96%)等大陆性季风和亚热带季风气候区;发病月份主要集中于夏秋两季(均为27例,各占42.19%)。病例中35例(35/62,占56.45%)明确患者与犬接触。结论我国结膜吸吮线虫病病例主要分布于黄河和长江流域等大陆性季风和亚热带季风气候区,各年龄段、各性别人群均有患病,临床症状和体征均较复杂。预防结膜吸吮线虫病需注意个人卫生、减少与流行区犬的接触,同时还需在户外活动时加强个人防护。
