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Temperature-dependent solubility of Rebaudioside A in methanol/ethanol and ethyl acetate mixtures:Experimental measurements and thermodynamic modeling

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Chinese Journal of Chemical Engineering 2024年第8期72卷 164-176页

作者： Zhenguang Liu Zexiang Ding yifeng cao Baojian Liu Qiwei Yang Zhiguo Zhang Qilong Ren Zongbi Bao Key Laboratory of Biomass Chemical Engineering of Ministry of Education College of Chemical and Biological EngineeringZhejiang UniversityHangzhou 310058China Institute of Zhejiang University-Quzhou Quzhou 324000China

The equilibrium solubility of Rebaudioside A(Reb A)FormⅡin binary mixtures of methanol/ethanol and ethyl acetate was quantitatively determined within the temperature range of 283.15—328.15 K at ambient *** experimental findings indicate a positive correlation between the solubility of Reb A(FormⅡ)and both the temperature and the methanol/ethanol content in the solvent *** describe the solubility data,six distinct models were employed:the modified Apelblat equation,theλh model,the combined nearly ideal binary solvent/Redlich—Kister(CNIBS/R—K)model,the van't HoffJouyban-Acree(VJA)model,the Apelblat-Jouyban-Acree(AJA)model,and the non-random two-liquid(NRTL)*** combined nearly ideal binary solvent/Redlich—Kister model exhibited the most precise fit for solubility in methanol+ethyl acetate mixtures,reflected by an average relative deviation(ARD)of 0.0011 and a root mean square deviation(RMSD)of 12×10^(-7).Conversely,for ethanol+ethyl acetate mixtures,the modified Apelblat equation provided a superior correlation(ARD=0.0014,RMSD=4×10^(-7)).Furthermore,thermodynamic parameters associated with the dissolution of Reb A(FormⅡ),including enthalpy,entropy,and the Gibbs energy change,were inferred from the *** findings underscore that the dissolution process is predominantly endothermic across the solvent systems ***,the entropy changes appear to have a significant influence on the Gibbs free energy associated with the dissolution of Reb A(FormⅡ),suggesting that entropic factors may play a pivotal role in the studied systems.

关键词： Rebaudioside A Solubility Thermodynamic modeling Dissolution Binary solvent

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基于支持向量机的风轮不平衡故障诊断方法研究

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太阳能学报 2024年第8期45卷 613-620页

作者：曹沂风华北电力大学国际教育学院保定071003

针对风电机组风轮不平衡的识别与检测问题,提出一种基于多核融合支持向量机的风轮不平衡识别方法。首先,分析风轮不平衡的影响,提出一种基于变分模态分解(VMD)的信号分解与重构方法;其次,提出基于模糊熵的风轮不平衡特征提取方法,以高... 详细信息

针对风电机组风轮不平衡的识别与检测问题,提出一种基于多核融合支持向量机的风轮不平衡识别方法。首先,分析风轮不平衡的影响,提出一种基于变分模态分解(VMD)的信号分解与重构方法;其次,提出基于模糊熵的风轮不平衡特征提取方法,以高斯核函数作为模糊函数,该方法具有较好的噪声鲁棒性和较低的数据长度依赖性;再次,提出基于多核融合支持向量机的风轮不平衡识别方法,融合不同特征和尺度的核函数组成核函数库,并选取最优核函数;最后,在不同湍流强度的仿真中建立交叉验证数据库对该方法进行验证,识别准确率在98%以上,证明该方法能有效识别风轮不平衡。

关键词：风电机组状态监测机器学习风轮不平衡模糊熵支持向量机

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基于演化聚类的网络舆情数据挖掘系统设计

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电子设计工程 2024年第3期32卷 139-142,147页

作者：曹宜丰河海大学商学院江苏常州213000

为了提升网络舆情数据挖掘的召回率、精度和查准率,设计一个基于演化聚类的网络舆情数据挖掘系统。从综合需求、功能需求两方面进行深入分析,确定挖掘系统的实际要求。构建挖掘系统整体架构,采用垂直化结构分别设计支撑层、数据层、服... 详细信息

为了提升网络舆情数据挖掘的召回率、精度和查准率,设计一个基于演化聚类的网络舆情数据挖掘系统。从综合需求、功能需求两方面进行深入分析,确定挖掘系统的实际要求。构建挖掘系统整体架构,采用垂直化结构分别设计支撑层、数据层、服务层、功能层,应用演化聚类建立舆情信息抓取关键词词库,计算随机演化初始向量,得到实验向量,分析不同维度的目标向量演化值,实现网络舆情抓取功能,确定适值函数实现信息挖掘。实验结果表明,设计系统的召回率能达到95%,精度能达到90%,且查准率接近99%,说明该系统的应用价值较高。

关键词：演化聚类网络舆情舆情数据数据挖掘挖掘系统

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离子液体强化不饱和键差异化合物分离的研究进展

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化工进展 2024年第1期43卷 198-214页

作者：容凡丁丁泽相曹义风陈俐吭杨柳申福星杨启炜鲍宗必浙江大学化学工程与生物工程学院浙江杭州310058 浙江大学衢州研究院浙江衢州324000

结构相似物的分离是物耗和能耗最集中的化工过程之一。对于具有不饱和键差异的化合物而言,它们的物化性质极为相近,高效分离极具挑战。离子液体因其特殊的理化性质、结构可设计以及多重分子间相互作用位点等特点而广泛应用于不饱和键差... 详细信息

结构相似物的分离是物耗和能耗最集中的化工过程之一。对于具有不饱和键差异的化合物而言,它们的物化性质极为相近,高效分离极具挑战。离子液体因其特殊的理化性质、结构可设计以及多重分子间相互作用位点等特点而广泛应用于不饱和键差异化合物的分子辨识分离。本文综述了离子液体强化不饱和键差异化合物分离的研究进展,重点介绍了常温常压下为气态的低碳烃、液态的中等碳链烃及固态的天然活性同系物等代表性体系的分离,突出了离子液体分离不饱和键差异化合物的构效关系、分离机理及分离工艺流程评价,并展望了离子液体强化不饱和键差异化合物分离的未来方向。

关键词：离子液体分子辨识分离萃取选择性不饱和键

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腹腔镜手术在消化道穿孔中的运用分析

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世界复合医学 2024年第3期10卷 168-171页

作者：陆宇曹亿峰常熟市支塘人民医院普外科江苏常熟215531

目的探讨消化道穿孔治疗中腹腔镜手术应用效果。方法随机选取2020年9月—2023年3月常熟市支塘人民医院收治的70例消化道穿孔患者作为研究对象,以随机数表法将其分为对照组(n=35,传统开腹手术)和观察组(n=35,腹腔镜手术)。对比两组手术... 详细信息

目的探讨消化道穿孔治疗中腹腔镜手术应用效果。方法随机选取2020年9月—2023年3月常熟市支塘人民医院收治的70例消化道穿孔患者作为研究对象,以随机数表法将其分为对照组(n=35,传统开腹手术)和观察组(n=35,腹腔镜手术)。对比两组手术相关指标、术后疼痛情况、临床疗效、术后感染发生率。结果观察组术中出血量为(24.50±5.51)mL、切口长度(2.40±0.78)cm、术后排气时间为(23.11±1.43)h、住院时间为(3.70±0.35)d,均低于对照组[术中出血量(27.66±6.62)mL、切口长度(10.90±1.15)cm、术后排气时间(62.25±3.62)h、住院时间(7.90±2.41)d],差异有统计学意义(t=2.170、36.189、59.492、10.203,P均<0.05)。观察组术后疼痛情况、临床疗效、术后感染发生率等指标优于对照组,差异有统计学意义(P均<0.05)。结论采用腹腔镜手术治疗消化道穿孔,可实现缩短手术时间、减少术中出血量的目标,有助于缓解术后疼痛。

关键词：腹腔镜手术消化道穿孔术中出血量临床疗效

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Intrinsic persistent room temperature phosphorescence derived from 1H-benzo[f]indole itself as a guest

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Chinese Chemical Letters 2023年第7期34卷 449-453页

作者： Danman Guo Yuyuan Wang Jinzheng Chen yifeng cao Yiling Miao Huahua Huang Zhenguo Chi Zhiyong Yang Key Laboratory for Polymeric Composite and Functional Materials of Ministry of Education Guangdong Engineering Technology Research Center for High-performance Organic and Polymer Photoelectric Functional FilmsSchool of ChemistrySun Yat-sen UniversityGuangzhou 510275China School of Materials Science and Engineering Sun Yat-sen UniversityGuangzhou 510275China Guangdong Provincial Key Laboratory of Optical Chemicals XinHuaYue GroupMaoming 525000China

The influence of 1H-benzo[f]indole(Bd) and its derivatives on room temperature phosphorescence(RTP)has raised great concern since they were found to significantly affect RTP of the extensively studied carbazole(Cz) derivatives. However, the role of Bd itself existing in Cz-based or other doping systems was still unclear. In order to clarify its intrinsic phosphorescent property, Bd was introduced as a guest into different organic matrixes including substituted Cz derivatives and polymers. The phosphorescence located in 560–620 nm was confirmed to be derived from Bd itself, which can be detected whatever Bd was doped in the crystal or amorphous state of Cz derivatives. The suitable energy gap between Cz derivatives and Bd is the key to achieve ultralong RTP of Bd. Additionally, when doped in polymers with plenty of hydrogen bonds, RTP of Bd with lifetime over 280 ms was easily obtained. Among them, Bd@PHEMA(poly(hydroxyethyl methacrylate) exhibited superior phosphorescence, with yellow afterglow lasting for over 2.5 s. Therefore, this work demonstrated that a new organic RTP phosphor, Bd, is discovered, and ultralong RTP of Bd can be achieved not only doped in Cz derivatives but also in polymers as the hosts.

关键词： Room temperature phosphorescence Host-guest 1H-benzo[f]indole Amorphous Hydrogen bonding

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一种新型1000MW超临界锅炉水冷壁爬壁机器人结构设计

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无线互联科技 2024年第5期21卷 48-51页

作者：奚林根王志刚曹一峰黄贤明江苏常熟发电有限公司江苏苏州215500 常熟理工学院江苏苏州215500

锅炉水冷壁稳定运行是火电厂安全生产的重要保障,目前国内外锅炉水冷壁的巡检工作主要以目视检验、卡尺测量、超声波测厚仪检测壁厚、电筒照射检查等人工方式进行,巡检周期长且精度低。文章结合计算机视觉、电磁超声无损检测、自动化等... 详细信息

锅炉水冷壁稳定运行是火电厂安全生产的重要保障,目前国内外锅炉水冷壁的巡检工作主要以目视检验、卡尺测量、超声波测厚仪检测壁厚、电筒照射检查等人工方式进行,巡检周期长且精度低。文章结合计算机视觉、电磁超声无损检测、自动化等技术,设计了一种新型的锅炉水冷壁爬壁机器人,致力于解决困扰火电行业已久的缺少有效评估检查锅炉水冷壁外观磨损及内部腐蚀状态的评估问题。

关键词：水冷壁爬壁机器人结构设计磁吸式

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Anisotropy Engineering Edge Magnetism in Zigzag Honeycomb Nanoribbons

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Chinese Physics Letters 2019年第6期36卷 83-87页

作者： Baoyue Li yifeng cao Lin Xu Guang Yang Zhi Ma Miao Ye Tianxing Ma School of Physics and Electronic-Electrical Engineering Ningxia UniversityYinchuan 750021 Department of Physics Beijing Normal UniversityBeijing 100875 School of Science Hebei University of Science and TechnologyShijiazhuang 050018 College of Information Science and Engineering Guilin University of TechnologyGuilin 541004

It has been demonstrated that the zigzag honeycomb nanoribbons exhibit an intriguing edge magnetism. Here the effect of the anisotropy on the edge magnetism in zigzag honeycomb nanoribbons is investigated using two kinds of large-scale quantum Monte Carlo simulations. The anisotropy in zigzag honeycomb nanoribbons is characterized by the ratios of nearest-neighbor hopping integrals t_1 in one direction and t_2 in another direction. Considering the electron-electron correlation, it is shown that the edge ferromagnetism could be enhanced greatly as t_2/|t_1|increases from 1 to 3, which not only presents an avenue for the control of this magnetism but is also useful for exploring further novel magnetism in new nano-scale materials.

关键词： Anisotropy Engineering Edge Magnetism Zigzag Honeycomb Nanoribbons edge magnetism

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From 0D to 3D:Hierarchical structured high-performance free-standing silicon anodes based on binder-induced topological network architecture

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Journal of Energy Chemistry 2024年第6期93卷 16-23,I0002页

作者： Yihong Tong Ruicheng cao Guanghui Xu yifeng Xia Hongyuan Xu Hong Jin Hui Xu Xi’an Jiaotong University Suzhou Academy Suzhou 215123JiangsuChina Nano Science and Technology Institute University of Science and Technology of ChinaSuzhou 215123JiangsuChina

Free-standing silicon anodes with high proportion of active materials have aroused great attention;however,the mechanical stability and electrochemical performance are severely ***,to resolve the appeal issues,a free-standing anode with a"corrugated paper"shape on micro-scale and a topological crosslinking network on the submicron and nano-scale is ***,an integrated three-dimensional electrode structure is constructed based on robust carbon nanotubes network with firmly anchored SiNPs via forming interlocking *** which,the hierarchical interlocking structure is achieved by directional induction of the binder,which ensures well integration during cycling so that significantly enhances mechanical stability as well as electronic and ionic conductivity of *** from it,this anode exhibits outsta nding performance under harsh service conditions including high Si loading,ultrahigh areal capacity(33.2 mA h cm^(-2)),and high/low temperatures(-15-60℃),which significantly extends its practical ***,the optimization mechanism of this electrode is explored to verify the crack-healing and structure-integration maintaining along cycling via a unique self-stabilization ***,from both the fundamental and engineering views,this strategy offers a promising path to produce high-performance free-standing electrodes for flexible device applications especially facing volume effect challenges.

关键词： Topological network Self-stabilization Flexibility Free-standing Silicon anode

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Evaluation of the relative risk of stroke in patients with hypertension using cerebrovascular hemodynamic accumulative score

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Frontiers of Medicine 2007年第3期1卷 274-278页

作者： HUANG Jiuyi WANG Guiqing GUO Jiping cao yifeng WANG Yan YANG Yongju YU Xuehai Shanghai Institute of Cerebrovascular Disease Control Shanghai 201318China

The relative risk(RR)of stroke in patients with hypertension was evaluated by using synthetic index of cerebrovascular hemodynamics.A total of 7,371 patients with hypertension with ages i40 years were selected from a population-based cohort study of the risk factors for *** data on the baseline investigation of risk factors,the determination of cerebrovascular hemodynamic parameters(CVHP),and stroke follow-up were *** RR of stroke in patients with hypertension was evaluated by CVHP *** analysis indicated that hypertension,complicated by other risk factors,had significant statistical association with the onset of *** for stroke when hypertension complicated with decrease of hemodynamic scores,heart disease,cigarette smoking and alcohol consumption were 4.93(95%CI,3.26–7.45),1.90(95%CI,1.36–2.66),1.99(95%CI,1.42–2.79)and 1.73(95%CI,1.19–2.53)*** multivariate analysis,hemodynamic score,age,sex,cigarette smoking,family history of stroke and systolic blood pressure were selected by the Cox regression for inclusion in the final *** them,the RR of hemodynamic score was *** analysis of doseresponse relationships indicated that when the hemodynamic scores in patients with hypertension were lower than 75 points,the RR of stroke at 75,60,45,30 and 15 points were 2.85,4.43,4.54,5.40 and 9.88,*** risk of stroke in patients with hypertension is closely asso ciated with hemodynamic impairment and the hemodynamic score may be used for quantitative evaluation of relative risks of stroke.

关键词： hypertension stroke hemodynamic processes cohort studies

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