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Oxidative Desulfurization of Fuel Oil with H_(3)PO_(4)-based Deep Eutectic Solvents
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作者 Li Xiuping Zhang Jiayin +1 位作者 Hou Liangpei Zhao Rongxiang 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS CSCD 2024年第2期178-186,共9页
A series of Lewis-acid deep eutectic solvents (DESs) were synthesized by stirring phosphoric acid and zincchloride as raw materials at 80℃ to form H_(3)PO_(4)/nZnCl_(2) (n = 0.1, 0.25, 0.5, 0.75, 1). The DESs were ch... A series of Lewis-acid deep eutectic solvents (DESs) were synthesized by stirring phosphoric acid and zincchloride as raw materials at 80℃ to form H_(3)PO_(4)/nZnCl_(2) (n = 0.1, 0.25, 0.5, 0.75, 1). The DESs were characterized byFourier transform infrared spectrophotometry (FT-IR), thermogravimetry/differential thermogravimetry (TG/DTG), andelectron spray ionization mass spectrometry (ESI-MS). The DESs were used as both extractants and catalysts to removedibenzothiophene from fuels via oxidative desulfurization (ODS). Experiments were performed to investigated the influenceof factors such as composition of DES, temperature, oxidant dosage (molar ratio of O:S), DES dosage (volume ratio ofDES:oil), and number of cycles on desulfurization rate. The results indicated that the removal rate of dibenzothiophene (DBT)was affected by the Lewis acidic DESs, with that of H_(3)PO_(4)/0.25∙ZnCl_(2) reaching 96.4% under optimal conditions (Voil=5 mL,VDES=1 mL, an oxidant dosage of 6, T=50 ℃). After six cycles, the desulfurization rate of H_(3)PO_(4)/0.25∙ZnCl_(2) remained above94.1%. The apparent activation energy of dibenzothiophene (DBT) removal reaction was determined by a pseudo-first orderkinetic equation according to the Arrhenius equation to be 32.34 kJ/mol, as estimated. A reaction mechanism is proposedbased on the experimental data and characterization results. 展开更多
关键词 deep eutectic solvents phosphoric acid zinc chloride oxidative desulfurization
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Machine-Learning-Assisted Design of Deep Eutectic Solvents Based on Uncovered Hydrogen Bond Patterns
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作者 Usman L.Abbas Yuxuan Zhang +4 位作者 Joseph Tapia Selim Md Jin Chen Jian Shi Qing Shao 《Engineering》 SCIE EI CAS CSCD 2024年第8期74-83,共10页
Non-ionic deep eutectic solvents(DESs)are non-ionic designer solvents with various applications in catalysis,extraction,carbon capture,and pharmaceuticals.However,discovering new DES candidates is challenging due to a... Non-ionic deep eutectic solvents(DESs)are non-ionic designer solvents with various applications in catalysis,extraction,carbon capture,and pharmaceuticals.However,discovering new DES candidates is challenging due to a lack of efficient tools that accurately predict DES formation.The search for DES relies heavily on intuition or trial-and-error processes,leading to low success rates or missed opportunities.Recognizing that hydrogen bonds(HBs)play a central role in DES formation,we aim to identify HB features that distinguish DES from non-DES systems and use them to develop machine learning(ML)models to discover new DES systems.We first analyze the HB properties of 38 known DES and 111 known non-DES systems using their molecular dynamics(MD)simulation trajectories.The analysis reveals that DES systems have two unique features compared to non-DES systems:The DESs have①more imbalance between the numbers of the two intra-component HBs and②more and stronger inter-component HBs.Based on these results,we develop 30 ML models using ten algorithms and three types of HB-based descriptors.The model performance is first benchmarked using the average and minimal receiver operating characteristic(ROC)-area under the curve(AUC)values.We also analyze the importance of individual features in the models,and the results are consistent with the simulation-based statistical analysis.Finally,we validate the models using the experimental data of 34 systems.The extra trees forest model outperforms the other models in the validation,with an ROC-AUC of 0.88.Our work illustrates the importance of HBs in DES formation and shows the potential of ML in discovering new DESs. 展开更多
关键词 Machine learning Deep eutectic solvents Molecular dynamics simulations Hydrogen bond Molecular design
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Stoichiometry and Stability Constant Values for Copper (II) Chelates with Ethylene Diamine in Deep Eutectic Solvents (DES) (Ethaline) Solutions
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作者 Khalid El Ttaib Abdolhadi Benhmid Rifat Hasan Omar 《Open Journal of Applied Sciences》 2024年第9期2592-2609,共18页
In this study we used the deep eutectic solvents (ionic liquids) to investigate the reaction between copper (II) with ethylene diamine (en). Two of the existing methods for analyzing spectrophotometric measurements ha... In this study we used the deep eutectic solvents (ionic liquids) to investigate the reaction between copper (II) with ethylene diamine (en). Two of the existing methods for analyzing spectrophotometric measurements have been applied for establishing, the stoichiometry and whenever possible, the stability constants of the chelates formed. The method of continuous variations was necessary to determine first whether, the metal ion and the ligand ethylene diamine form one or more than one chelate, when more than one chelate formed, the results obtained depend on the wavelength and for meaningful conclusions the wavelengths were carefully selected. The empirical formulae of the chelates were further substantiated by the molar ratio method. The effect of time and temperature on the formation and stability of these chelates in solution is also studied. The stability constants, K1 and K2 for the copper (II) chelates were calculated, though reliable, and are comparable to literature values. 展开更多
关键词 CU(II) Ethylene Diamine (en) Deep Eutectic solvents Job’s Method Ionic Liquids and Stability Constant
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基于改进DES算法的网络链路安全通信方法
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作者 吴静莉 《无线互联科技》 2024年第18期47-49,共3页
现有的安全通信方法受限于60000 kB数据量,存在摘要对等数目不稳定的问题。为此,文章提出基于改进DES算法的网络链路安全通信方法。该方法通过网络链路安全协议建立连接,验证双方身份;利用最短路径优先协议,结合数据库信息,确保可信连... 现有的安全通信方法受限于60000 kB数据量,存在摘要对等数目不稳定的问题。为此,文章提出基于改进DES算法的网络链路安全通信方法。该方法通过网络链路安全协议建立连接,验证双方身份;利用最短路径优先协议,结合数据库信息,确保可信连接适应网络环境;基于密文位数,使用DES算法延长密钥,使之与明文位数匹配;设置访问权限,运用双线性映射配对特定属性,并通过加密算法处理,实现安全通信。实验证明,传输数据量稳定在90000 kB,提升了效率,解决了摘要对等数目不稳定的问题,提高了通信性能。 展开更多
关键词 des算法 网络链路 安全通信 改进算法
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DES+CTAB复配驱油剂体系提高低渗致密砂岩油藏采收率机理 被引量:1
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作者 白佳佳 司双虎 +5 位作者 陶磊 王国庆 王龙龙 史文洋 张娜 朱庆杰 《岩性油气藏》 CAS CSCD 北大核心 2024年第1期169-177,共9页
针对低渗致密油藏注水困难、采收率低等问题,利用尿素基深共晶溶剂(DES)与十六烷基三甲基溴化铵(CTAB)复配的驱油剂体系,对驱油剂在低渗致密油藏中的降压增注和提高采收率机理进行了研究。研究结果表明:①驱油剂体系可以将油水界面张力... 针对低渗致密油藏注水困难、采收率低等问题,利用尿素基深共晶溶剂(DES)与十六烷基三甲基溴化铵(CTAB)复配的驱油剂体系,对驱油剂在低渗致密油藏中的降压增注和提高采收率机理进行了研究。研究结果表明:①驱油剂体系可以将油水界面张力降低至10^(-3)mN/m以下,大大提高了洗油效率;②驱油剂体系可有效抑制黏土矿物水化,避免了低渗致密砂岩中黏土矿物水化膨胀带来的流体敏感性损害;③驱油剂体系可对砂岩表面进行界面修饰,驱油剂溶液浸泡后样品的油相接触角由25.8°增加至61.4°,亲水性增强,亲油性减弱,有助于吸附在岩石孔隙壁面的油膜脱落;④超前注入驱油剂的注入压力降低率平均为79.64%,采收率平均为50.96%,远大于常规水驱(一次注水→注驱油剂驱→二次注水)的采收率。 展开更多
关键词 低渗致密砂岩油藏 尿素基深共晶溶剂(des) 十六烷基三甲基溴化铵(CTAB) 水驱 黏土矿物水化膨胀 表面活性剂 提高采收率
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Des(rhamnosyl)verbascoside抗HBV作用的定量蛋白质组学研究
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作者 邓洁 赵童诗尧 +2 位作者 牟俊飞 梁成钦 周先丽 《广西科学》 CAS 北大核心 2024年第1期197-204,共8页
为探究des(rhamnosyl)verbascoside体外抗乙型肝炎病毒(HBV)的活性作用和机制,本研究以des(rhamnosyl)verbascoside为实验药物对HepG2.2.15细胞进行干预,实验分为药物干预组和对照组,采用串联质谱标签(Tandem Mass Tag,TMT)蛋白质组学... 为探究des(rhamnosyl)verbascoside体外抗乙型肝炎病毒(HBV)的活性作用和机制,本研究以des(rhamnosyl)verbascoside为实验药物对HepG2.2.15细胞进行干预,实验分为药物干预组和对照组,采用串联质谱标签(Tandem Mass Tag,TMT)蛋白质组学方法对提取的总蛋白进行分析。结果表明,共筛选得到300个差异表达蛋白,其中有109个上调蛋白,191个下调蛋白。基因本体论(Gene Ontology,GO)分析结果显示,差异蛋白主要参与DNA复制(DNA replication)、鞘糖脂代谢(Glycosphingolipid metabolic process)、细胞增殖(Cell proliferation)、寡糖分解代谢(Oligosaccharide catabolic process)等生物学过程,以及DNA聚合酶活性(DNA polymerase activity)、丝氨酸型羧肽酶活性(Serine type carboxypeptidase activity)、DNA引物酶活性(DNA primase activity)等分子功能。京都基因与基因组百科全书(Kyoto Encyclopedia of Genes and Genomes,KEGG)分析结果显示,差异蛋白主要参与细胞代谢(Metabolism)、遗传信息传导(Genetic information processing)、生物系统通路(Organismal systems)等相关信号通路。亚细胞定位分析表明,差异蛋白大多定位在细胞质和细胞核。本研究共筛选出13个与抗HBV密切相关的蛋白。通过定量蛋白组学初步揭示des(rhamnosyl)verbascoside可能通过增加HGF、SORT1、MAN2B1,减少PRIM1、PRIM2、POLA1、POLD3、POLD2、POLD1、POLE、ERCC2、LAMC1、SDC1等蛋白表达来起到体外抗HBV的作用。 展开更多
关键词 des(rhamnosyl)verbascoside 蛋白组学 乙型肝炎病毒 生物信息学 旱田草
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Theoretical analysis of hydrogen solubility in direct coal liquefaction solvents 被引量:1
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作者 Xiaobin Zhang Aoqi Wang +1 位作者 Xingbao Wang Wenying Li 《International Journal of Coal Science & Technology》 EI CAS CSCD 2024年第2期187-197,共11页
The cyclic hydrogenation technology in a direct coal liquefaction process relies on the dissolved hydrogen of the solvent or oil participating in the hydrogenation reaction.Thus,a theoretical basis for process optimiz... The cyclic hydrogenation technology in a direct coal liquefaction process relies on the dissolved hydrogen of the solvent or oil participating in the hydrogenation reaction.Thus,a theoretical basis for process optimization and reactor design can be established by analyzing the solubility of hydrogen in liquefaction solvents.Experimental studies of hydrogen solubility in liquefaction solvents are challenging due to harsh reaction conditions and complex solvent compositions.In this study,the composition and content of liquefied solvents were analyzed.As model compounds,hexadecane,toluene,naphthalene,tetrahydronaphthalene,and phenanthrene were chosen to represent the liquefied solvents in chain alkanes and monocyclic,bicyclic,and tricyclic aromatic hydrocarbons.The solubility of hydrogen X(mol/mol)in pure solvent components and mixed solvents(alkanes and aromatics mixed in proportion to the chain alkanes+bicyclic aromatic hydrocarbons,bicyclic saturated aromatic hydrocarbons+bicyclic aromatic hydrocarbons,and bicyclic aromatic hydrocarbons+compounds containing het-eroatoms composed of mixed components)are determined using Aspen simulation at temperature and pressure conditions of 373–523 K and 2–10 MPa.The results demonstrated that at high temperatures and pressures,the solubility of hydrogen in the solvent increases with the increase in temperature and pressure,with the pressure having a greater impact.Further-more,the results revealed that hydrogen is more soluble in straight-chain alkanes than in other solvents,and the solubility of eicosanoids reaches a maximum of 0.296.The hydrogen solubility in aromatic ring compounds decreased gradually with an increase in the aromatic ring number.The influence of chain alkanes on the solubility of hydrogen predominates in a mixture of solvents with different mixing ratios of chain alkanes and aromatic hydrocarbons.The solubility of hydrogen in mixed aromatic solvents is less than that in the corresponding single solvents.Hydrogen is less soluble in solvent compounds containing heteroatoms than in compounds without heteroatoms. 展开更多
关键词 Direct coal liquefaction Liquefaction solvents Process simulation Hydrogen solubility
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融合DES和ECC算法的物联网隐私数据加密方法
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作者 唐锴令 郑皓 《吉林大学学报(信息科学版)》 CAS 2024年第3期496-502,共7页
为避免物联网隐私数据在加密过程中产生较多重复数据,导致计算复杂度较高,降低计算效率和安全性问题,提出融合DES(Data Encryption Standard)和ECC(Ellipse Curve Ctyptography)算法的物联网隐私数据加密方法。首先,采用TF-IDF(Tem Freq... 为避免物联网隐私数据在加密过程中产生较多重复数据,导致计算复杂度较高,降低计算效率和安全性问题,提出融合DES(Data Encryption Standard)和ECC(Ellipse Curve Ctyptography)算法的物联网隐私数据加密方法。首先,采用TF-IDF(Tem Frequency-Inverse Document Frequency)算法提取物联网隐私数据中的特征向量,输入BP(Back Propagation)神经网络中并进行训练,利用IQPSO(Improved Quantum Particle Swarm Optimization)算法优化神经网络,完成对物联网隐私数据中重复数据的去除处理;其次,分别利用DES算法和ECC算法对物联网隐私数据实施一、二次加密;最后,采取融合DES和ECC算法进行数字签名加密,实现对物联网隐私数据的完整加密。实验结果表明,该算法具有较高的计算效率、安全性以及可靠性。 展开更多
关键词 des算法 ECC算法 物联网数据加密 TF-IDF算法 IQPSO算法 数字签名
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DES改变胺单体扩散速率制备高性能复合反渗透膜
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作者 何金 赖裕文 +3 位作者 李艳春 周士林 周勇 高从堦 《化工进展》 EI CAS CSCD 北大核心 2024年第4期1972-1980,共9页
在常用的提高复合膜性能的方法中,调控复合膜形成的关键步骤界面聚合(IP)是一种简单且有效的方法。然而,对低共熔溶剂在界面聚合过程中的影响研究相对较少,在此,本文提出了将低共熔溶剂(DES)引入界面聚合过程中,制备了聚酰胺复合反渗透... 在常用的提高复合膜性能的方法中,调控复合膜形成的关键步骤界面聚合(IP)是一种简单且有效的方法。然而,对低共熔溶剂在界面聚合过程中的影响研究相对较少,在此,本文提出了将低共熔溶剂(DES)引入界面聚合过程中,制备了聚酰胺复合反渗透膜。采用傅里叶红外光谱(FTIR)、X射线光电子能谱(XPS)、场发射扫描电镜(SEM)和原子力显微镜(AFM)等对复合膜的结构和物化性质进行了表征。考察了DES的加入量对反渗透膜性能的影响,并系统地分析了黏度对胺单体扩散速率的影响。得出了DES添加量为5%时,复合膜综合性能最佳,通量为63L/(m^(2)·h),截留率为99%。研究结果表明:DES的掺入使膜表面粗糙度降低、亲水性和电负性增强,此外,相比于未改性的复合膜,DES改性后的复合反渗透膜通量都有所提升。这项工作对制备出高性能的复合膜具有重要意义。 展开更多
关键词 聚合 扩散 低共熔溶剂 反渗透
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DES合成高活性CoCO_(3)纳米片及析氧反应性能研究
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作者 刘亚超 谭晓杰 +4 位作者 李旭东 王瑞 王慧 韩璇 赵青山 《化工学报》 EI CSCD 北大核心 2024年第9期3320-3328,共9页
氢能因其热值高、清洁无污染等优势,被认为是实现碳中和最有效的能源载体之一。电解水制氢是实现可持续制氢的有效途径。其中,析氧反应(OER)缓慢动力学过程导致水分解效率低下,迫切需要开发高效、稳定的电催化剂。利用多元醇、尿素与CoC... 氢能因其热值高、清洁无污染等优势,被认为是实现碳中和最有效的能源载体之一。电解水制氢是实现可持续制氢的有效途径。其中,析氧反应(OER)缓慢动力学过程导致水分解效率低下,迫切需要开发高效、稳定的电催化剂。利用多元醇、尿素与CoCl_(2)·6H_(2)O之间的配位作用形成超分子三元低共熔溶剂(DES)体系,通过一锅溶剂热法构建表面粗糙的二维CoCO_(3)纳米片,用于提升电催化OER效率,并针对醇羟基数量对CoCO_(3)形貌及性能影响进行了探究。研究表明,丙三醇、尿素和CoCl_(2)·6H_(2)O三元DES体系制备的CoCO_(3)-Gly催化剂,呈现更蓬松、更薄、更粗糙的片状结构,具有更加优异的OER性能,电流密度在10 mA·cm-2时过电位311 mV,经24 h稳定性测试电流保留率达99%。 展开更多
关键词 低共熔溶剂 碳酸钴 催化剂 电催化 析氧反应 多元醇
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胆碱基DES在EOR及CCUS中的应用与展望
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作者 白佳佳 陈掌星 +2 位作者 康毅力 陈明君 陶磊 《西南石油大学学报(自然科学版)》 CAS CSCD 北大核心 2024年第3期66-76,共11页
深共晶溶剂(Deep Eutectic Solvent,DES)具有低饱和蒸气压、不易燃、不易爆、无毒、易降解、电化学和热稳定性好等优点。DES具有很好的表面活性,DES中的氢键网络与阴、阳离子表面活性剂具有很好的协同驱油作用。关于DES与常用表面活性... 深共晶溶剂(Deep Eutectic Solvent,DES)具有低饱和蒸气压、不易燃、不易爆、无毒、易降解、电化学和热稳定性好等优点。DES具有很好的表面活性,DES中的氢键网络与阴、阳离子表面活性剂具有很好的协同驱油作用。关于DES与常用表面活性剂的协同作用研究尚处于起步阶段,二者复配体系提高采收率(Enhanced Oil Recovery,EOR)机理尚不明确。在全面分析归纳总结胆碱基DES物理化学性质的基础上,探究了DES及其与阴或阳离子表面活性剂复配体系EOR机理,揭示了DES吸收二氧化碳机理,提出了DES在稠油油藏、低渗透油藏EOR以及碳捕集、利用与封存(Carbon Capture,Utilization and Storage,CCUS)中的应用建议。研究结果对DES在EOR和CCUS的应用推广具有重要的指导意义。 展开更多
关键词 氯化胆碱基深共晶溶剂 化学驱 氢键 提高采收率 碳捕集、利用与封存
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Alcohol solvent effect on the self-assembly behaviors of lignin oligomers
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作者 Ya Ma Zhicheng Jiang +4 位作者 Yafei Luo Xingjie Guo Xudong Liu Yiping Luo Bi Shi 《Green Energy & Environment》 SCIE EI CAS CSCD 2024年第4期597-603,共7页
The interactions between lignin oligomers and solvents determine the behaviors of lignin oligomers self-assembling into uniform lignin nanoparticles(LNPs).Herein,several alcohol solvents,which readily interact with th... The interactions between lignin oligomers and solvents determine the behaviors of lignin oligomers self-assembling into uniform lignin nanoparticles(LNPs).Herein,several alcohol solvents,which readily interact with the lignin oligomers,were adopted to study their effects during solvent shifting process for LNPs’production.The lignin oligomers with widely distributed molecular weight and abundant guaiacyl units were extracted from wood waste(mainly consists of pine wood),exerting outstanding self-assembly capability.Uniform and spherical LNPs were generated in H_(2)O-n-propanol cosolvent,whereas irregular LNPs were obtained in H_(2)O-methanol cosolvent.The unsatisfactory self-assembly performance of the lignin oligomers in H_(2)O-methanol cosolvent could be attributed to two aspects.On one hand,for the initial dissolution state,the distinguishing Hansen solubility parameter and polarity between methanol solvent and lignin oligomers resulted in the poor dispersion of the lignin oligomers.On the other hand,strong hydrogen bonds between methanol solvent and lignin oligomers during solvent shifting process,hindered the interactions among the lignin oligomers for self-assembly. 展开更多
关键词 Lignin oligomers Alcohol solvent SELF-ASSEMBLY LNPs solvent effects
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Solvent transport dynamics and its effect on evolution of mechanical properties of nitrocellulose(NC)-based propellants under hot-air drying process
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作者 Enfa Fu Mingjun Yi +1 位作者 Qianling Liu Zhenggang Xiao 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第2期262-270,共9页
Appropriate drying process with optimized controlling of drying parameters plays a vital role in the improvement of the quality and performance of propellant products.However,few research on solvent transport dynamics... Appropriate drying process with optimized controlling of drying parameters plays a vital role in the improvement of the quality and performance of propellant products.However,few research on solvent transport dynamics within NC-based propellants was reported,and its effect on the evolution of mechanical properties was not interpreted yet.This study is conducted to gain a comprehensive understanding of hot-air drying for NC-based propellants and clarify the effect of temperature on solvent transport behavior and further the change of mechanical properties during drying.The drying kinetic curves show the drying time required is decreased but the steady solvent content is increased and the drying rate is obviously increased with the increase of hot-air temperatures,indicating hot-air temperatures have a significant effect on drying kinetics.A modified drying model was established,and results show it is more appropriate to describe solvent transport behavior within NC-based propellants.Moreover,two linear equations were established to exhibit the relationship between solvent content and its effect on the change of tensile properties,and the decrease of residual solvent content causes an obvious increase of tensile strength and tensile modulus of propellant products,indicating its mechanical properties can be partly improved by adjustment of residual solvent content.The outcomes can be used to clarify solvent transport mechanisms and optimize drying process parameters of double-based gun propellants. 展开更多
关键词 Nitrocellulose-based propellants solvent transport dynamics Mechanical properties Drying kinetics Effective solvent diffusion coefficient
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Simultaneous purification of minor components in natural products using twin-column recycling chromatography with a step solvent gradient
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作者 Guangxia Jin Yuxue Wu Feng Wei 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第5期212-219,共8页
The isolation of minor components from complex natural product matrices presents a significant challenge in the field of purification science due to their low concentrations and the presence of structurally similar co... The isolation of minor components from complex natural product matrices presents a significant challenge in the field of purification science due to their low concentrations and the presence of structurally similar compounds.This study introduces an optimized twin-column recycling chromatography method for the efficient and simultaneous purification of these elusive constituents.By introducing water at a small flowing rate between the twin columns,a step solvent gradient is created,by which the leading edge of concentration band would migrate at a slower rate than the trailing edge as it flowing from the upstream to downstream column.Hence,the band broadening is counterbalanced,resulting in an enrichment effect for those minor components in separation process.Herein,two target substances,which showed similar peak position in high performance liquid chromatography(HPLC)and did not exceed 1.8%in crude paclitaxel were selected as target compounds for separation.By using the twin-column recycling chromatography with a step solvent gradient,a successful purification was achieved in getting the two with the purity almost 100%.We suggest this method is suitable for the separation of most components in natural produces,which shows higher precision and recovery rate compared with the common lab-operated separation ways for natural products(thin-layer chromatography and prep-HPLC). 展开更多
关键词 solvent gradient Twin-column recycling chromatography PURIFICATION Minor component Natural products
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Study on the green extraction of corncob xylan by deep eutectic solvent
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作者 Bingyu Jiao Le Wang +3 位作者 Haitao Gui Zifu Ni Rong Du Yuansen Hu 《Grain & Oil Science and Technology》 CAS 2024年第1期50-59,共10页
Corn as one of the world's major food crops,its by-product corn cob is also rich in resources.However,the unreasonable utilization of corn cob often causes the environmental pollution,waste of resources and other ... Corn as one of the world's major food crops,its by-product corn cob is also rich in resources.However,the unreasonable utilization of corn cob often causes the environmental pollution,waste of resources and other problems.As one of the most abundant polymers in nature,xylan is widely used in food,medicine,materials and other fields.Corn cob is rich in xylan,which is an ideal raw material for extracting xylan.However,the intractable lignin is covalently linked to xylan,which increases the difficulty of xylan extraction.It has been reported that the deep eutectic solvent(DES)could preferentially dissolve lignin in biomass,thereby dissolving the xylan.Then,the xylan in the extract was separated by ethanol precipitation method.The xylan precipitate was obtained after centrifugation,while the supernatant was retained.The components of the supernatant after ethanol precipitation were separated by the rotary evaporator.The ethanol,water and DES were collected for the subsequent extraction of corn cob xylan.In this study,a novel way was provided for the green production of corn cob xylan.The DES was used to extract xylan from corn cob which was used as the raw material.The effects of solid-liquid ratio,reaction time,reaction temperature and water content of DES on the extraction rate of corn cob xylan were investigated by the single factor test.Furthermore,the orthogonal test was designed to optimize the xylan extraction process.The structure of corn cob xylan was analyzed and verified.The results showed that the optimum extraction conditions of corn cob xylan were as follows:the ratio of corn cob to DES was 1:15(g:mL),the extraction time was 3 h,the extraction temperature was 60℃,and the water content of DES was 70%.Under these conditions,the extraction rate of xylan was 16.46%.The extracted corn cob xylan was distinctive triple helix of polysaccharide,which was similar to the structure of commercially available xylan.Xylan was effectively and workably extracted from corn cob by the DES method.This study provided a new approach for high value conversion of corn cob and the clean production of xylan. 展开更多
关键词 CORNCOB Deep eutectic solvent XYLAN Process optimization EXTRACTION
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基于DES算法的电力物联网信任网关数据远传加密 被引量:1
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作者 龙凤 饶玮 《长江信息通信》 2024年第2期23-24,29,共3页
基于DES算法的电力物联网信任网关数据远传加密是指在电力物联网中,通过信任网关对数据进行加密保护,使用DES算法进行数据加密,并通过远传方式将加密后的数据传输到目标节点。针对电力物联网信任网关的数据传输安全问题,提出了基于DES... 基于DES算法的电力物联网信任网关数据远传加密是指在电力物联网中,通过信任网关对数据进行加密保护,使用DES算法进行数据加密,并通过远传方式将加密后的数据传输到目标节点。针对电力物联网信任网关的数据传输安全问题,提出了基于DES算法的电力物联网关信任网关数据加密的传输方法。该方法在明文数据中加入了可变化的冗余码,既可以提高数据远传加密的可靠性,又可以将每个数据块经过一系列的操作得到密文,可防止数据被篡改提高其安全性。 展开更多
关键词 des算法 电力物联网 数据传输 网关 加密
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Insight into the experiment and extraction mechanism for separating carbazole from anthracene oil with quaternary ammonium-based deep eutectic solvents
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作者 Xudong Zhang Yanhua Liu +4 位作者 Jun Shen Yugao Wang Gang Liu Yanxia Niu Qingtao Sheng 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第1期188-199,共12页
Carbazole is an irreplaceable basic organic chemical raw material and intermediate in industry.The separation of carbazole from anthracene oil by environmental benign solvents is important but still a challenge in che... Carbazole is an irreplaceable basic organic chemical raw material and intermediate in industry.The separation of carbazole from anthracene oil by environmental benign solvents is important but still a challenge in chemical engineering.Deep eutectic solvents (DESs) as a sustainable green separation solvent have been proposed for the separation of carbazole from model anthracene oil.In this research,three quaternary ammonium-based DESs were prepared using ethylene glycol (EG) as hydrogen bond donor and tetrabutylammonium chloride (TBAC),tetrabutylammonium bromide or choline chloride as hydrogen bond acceptors.To explore their extraction performance of carbazole,the conductor-like screening model for real solvents (COSMO-RS) model was used to predict the activity coefficient at infinite dilution (γ^(∞)) of carbazole in DESs,and the result indicated TBAC:EG (1:2) had the stronger extraction ability for carbazole due to the higher capacity at infinite dilution (C^(∞)) value.Then,the separation performance of these three DESs was evaluated by experiments,and the experimental results were in good agreement with the COSMO-RS prediction results.The TBAC:EG (1:2) was determined as the most promising solvent.Additionally,the extraction conditions of TBAC:EG (1:2) were optimized,and the extraction efficiency,distribution coefficient and selectivity of carbazole could reach up to 85.74%,30.18 and 66.10%,respectively.Moreover,the TBAC:EG (1:2) could be recycled by using environmentally friendly water as antisolvent.In addition,the separation performance of TBAC:EG (1:2) was also evaluated by real crude anthracene,the carbazole was obtained with purity and yield of 85.32%,60.27%,respectively.Lastly,the extraction mechanism was elucidated byσ-profiles and interaction energy analysis.Theoretical calculation results showed that the main driving force for the extraction process was the hydrogen bonding ((N–H...Cl) and van der Waals interactions (C–H...O and C–H...π),which corresponding to the blue and green isosurfaces in IGMH analysis.This work presented a novel method for separating carbazole from crude anthracene oil,and will provide an important reference for the separation of other high value-added products from coal tar. 展开更多
关键词 CARBAZOLE Model anthracene oil Deep eutectic solvents COSMO-RS Extraction mechanism
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Reviewing electrochemical stability of ionic liquids-/deep eutectic solvents-based electrolytes in lithium-ion,lithium-metal and post-lithium-ion batteries for green and safe energy
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作者 Yu Chen Shuzi Liu +4 位作者 Zixin Bi Zheng Li Fengyi Zhou Ruifen Shi Tiancheng Mu 《Green Energy & Environment》 SCIE EI CAS CSCD 2024年第6期966-991,共26页
Sustainable energy is the key issue for the environment protection,human activity and economic development.Ionic liquids(ILs)and deep eutectic solvents(DESs)are dogmatically regarded as green and sustainable electroly... Sustainable energy is the key issue for the environment protection,human activity and economic development.Ionic liquids(ILs)and deep eutectic solvents(DESs)are dogmatically regarded as green and sustainable electrolytes in lithium-ion,lithium-metal(e.g.,lithium-sulphur,lithium-oxygen)and post-lithium-ion(e.g.,sodium-ion,magnesium-ion,and aluminum-ion)batteries.High electrochemical stability of ILs/DESs is one of the prerequisites for green,sustainable and safe energy;while easy electrochemical decomposition of ILs/DESs would be contradictory to the concept of green chemistry by adding the cost,releasing volatile/hazardous by-products and hindering the recyclability.However,(1)are ILs/DESs-based electrolytes really electrochemically stable when they are not used in batteries?(2)are ILs/DESs-based electrolytes really electrochemically stable in real batteries?(3)how to design ILs/DESs-based electrolytes with high electrochemical stability for batteries to achieve sustainability and green development?Up to now,there is no summary on this topic,to the best of our knowledge.Here,we review the effect of chemical structure and non-structural factors on the electrochemical stability of ILs/DESs in simulated conditions.More importantly,electrochemical stability of ILs/DESs in real lithium-ion,lithium-metal and post-lithium-ion batteries is concluded and compared.Finally,the strategies to improve the electrochemical stability of ILs/DESs in lithium-ion,lithium-metal and post-lithium-ion batteries are proposed.This review would provide a guide to design ILs/DESs with high electrochemical stability for lithium-ion,lithium-metal and postlithium-ion batteries to achieve sustainable and green energy. 展开更多
关键词 Green solvents Decomposition Sustainable chemistry Lithium-oxygen batteries Lithium-sulphur batteries Sodium-ion batteries
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Design method of extractant for liquid-liquid extraction based on elements and chemical bonds
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作者 Yuwen Wei Chunling Zhang +4 位作者 Yue Zhang Lili Wang Li Xia Xiaoyan Sun Shuguang Xiang 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第4期193-202,共10页
In the petrochemical industry process, the relative volatility between the components to be separated is close to one or the azeotrope that systems are difficult to separate. Liquid-liquid extraction is a common and e... In the petrochemical industry process, the relative volatility between the components to be separated is close to one or the azeotrope that systems are difficult to separate. Liquid-liquid extraction is a common and effective separation method, and selecting an extraction agent is the key to extraction technology research. In this paper, a design method of extractants based on elements and chemical bonds was proposed. A knowledge-based molecular design method was adopted to pre-select elements and chemical bond groups. The molecules were automatically synthesized according to specific combination rules to avoid the problem of “combination explosion” of molecules. The target properties of the extractant were set, and the extractant meeting the requirements was selected by predicting the correlation physical properties of the generated molecules. Based on the separation performance of the extractant in liquid-liquid extraction and the relative importance of each index, the fuzzy comprehensive evaluation membership function was established, the analytic hierarchy process determined the mass ratio of each index, and the consistency test results were passed. The results of case study based on quantum chemical analysis demonstrated that effective determination of extractants for the analysis of benzene-cyclohexane systems. The results unanimously prove that the method has important theoretical significance and application value. 展开更多
关键词 Molecular design Element and chemical bonds Molecular simulation THERMODYNAMICS solvent extraction
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Solvent effects on Diels-Alder reaction in ionic liquids:A reaction density functional study
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作者 Zijiang Dou Weiqiang Tang +1 位作者 Peng Xie Shuangliang Zhao 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第2期180-188,共9页
Extensive experimental studies have been performed on the Diels-Alder(DA)reactions in ionic liquids(ILs),which demonstrate that the IL environment can significantly influence the reaction rates and selectivity.However... Extensive experimental studies have been performed on the Diels-Alder(DA)reactions in ionic liquids(ILs),which demonstrate that the IL environment can significantly influence the reaction rates and selectivity.However,the underlying microscopic mechanism remains ambiguous.In this work,the multiscale reaction density functional theory is applied to explore the effect of 1-butyl-3-methylimidazolium hexafluorophosphate([BMIM][PF_(6)])solvent on the reaction of cyclopentadiene(CP)with acrolein,methyl acrylate,or acrylonitrile.By analyzing the free energy landscape during the reaction,it is found that the polarization effect has a relatively small influence,while the solvation effect makes both the activation free energy and reaction free energy decrease.In addition,the rearrangement of local solvent structure shows that the cation spatial distribution responds more evidently to the reaction than the anion,and this indicates that the cation plays a dominant role in the solvation effect and so as to affect the reaction rates and selectivity of the DA reactions. 展开更多
关键词 solvent effect Ionic liquids Diels-Alder reaction Reaction density functional theory
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