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喹啉羧酸共价有机框架微球在线固相萃取4种黄曲霉毒素

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分析测试学报 2025年第1期44卷 163-171页

作者：王荣雨刘杰周静李涛王晓纪文华齐鲁工业大学(山东省科学院)山东省分析测试中心天然产物分离提取共性技术创新与应用山东省工程研究中心山东济南250014 山东明仁福瑞达制药股份有限公司山东济南250014 山东蓝城分析测试有限公司山东济南250100

以1,3,5-三(4-氨基苯基)苯、联苯二甲醛、丙酮酸为合成反应单体,氨基磺酸为催化剂,利用Doebner串联反应成功制备了具有喹啉羧酸骨架的共价有机框架(QCA-COF)微球。通过优化反应条件发现,采用1,4-二氧六环-乙腈溶液(1∶4,体积比)作为反... 详细信息

以1,3,5-三(4-氨基苯基)苯、联苯二甲醛、丙酮酸为合成反应单体,氨基磺酸为催化剂,利用Doebner串联反应成功制备了具有喹啉羧酸骨架的共价有机框架(QCA-COF)微球。通过优化反应条件发现,采用1,4-二氧六环-乙腈溶液(1∶4,体积比)作为反应溶剂时,可获得具有微米级粒径的微球。采用扫描电子显微镜、红外光谱、X射线粉末衍射、N_(2)吸脱附实验对QCA-COF微球的结构进行表征。由于QCA-COF微球具有芳环、喹啉基团、羧基等官能团,可通过氢键、π-π等多重相互作用与黄曲霉毒素进行吸附,其吸附能力优于C_(18)、PSA以及GCB等商用材料。将QCA-COF材料作为在线固相萃取柱的填料,详细优化了在线固相萃取条件。将在线固相萃取柱与高效液相色谱联用,建立了4种黄曲霉毒素的检测方法,检出限为0.024~0.030 ng·g^(-1)。经方法学验证,该方法具有较好的回收率(82.5%~105%)和精密度(4.3%~10%,n=6),适用于花生、小麦、陈皮、杏仁、决明子等食品与中药材中4种黄曲霉毒素的测定。

关键词：黄曲霉毒素在线固相萃取共价有机框架高效液相色谱

Molecular Dynamics Simulation of Behaviours of Non-Polar Droplets Merging and Interactions with Hydrophobic Surfaces

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Journal of Bionic Engineering 2008年第4期5卷 271-281页

作者： Y.Y. Yan C.Y. ji School of the Built Environment University of Nottingham Nottingham NG7 2RD UK

This paper presents a molecular dynamics simulation of the behaviours of non-polar droplets merging and also the fluid molecules interacting with a hydrophobic surface. Such behaviours and transport phenomena are popular in general microchannel flow boiling and two-phase flow. The droplets are assumed to be composed of Lennards-Jones type molecules. Periodic boundary conditions are applied in three coordinate directions of a 3-D system, where there exist two liquid droplets and their vapour. The two droplets merge when they come within the prescribed small distance. The merging of two droplets apart from each other at different initial distances is tested and the possible larger （or critical） non-dimensional distance, in which droplets merging can occur, is discussed. The evolution of the merging process is simulated numerically by employing the Molecular Dynamics （MD） method. For interactions with hydrophobic solid wall, a system with fluid confined between two walls is used to study the wetting phenomena of fluid and solid wall. The results are compared with those of hydrophilic wall to show the unique characteristics of hydrophobic interactions by microscopic methods.

关键词： molecular dynamics simulation mist flow droplets merging hydrophobic wetting

Preliminary optimization of acupuncture regimen at Nèiguān(PC 6) for gastroesophageal reflux disease

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World Journal of Acupuncture-Moxibustion 2019年第2期29卷 123-126页

作者： ji ZHAng Department of Chinese Medicine Jiangsu Xiangshui County People's Hospital Xiangshui 224600 Jiangsu Province China

Objective:To optimize preliminarily acupuncture regimen for gastroesophageal reflux disease(GERD).Methods:A total of 80 patients of GERD were taken as the subjects in *** reflux disease questionnaire(RDQ)was adopted to assess the relevant *** orthogonal design method was used to observe the effects on GERD in acupuncture regimen with difference combinations among 5 factors and 2 levels at Nèiguān(内关 PC 6),including reinforcing-reducing technique by rotating needle(A),time of rotating needle(B),supplementary acupoint(C),time of needle retention(D)and treatment interval(E).The primary and secondary functions among 5 factors(variance analysis),advantages and disadvantages between 2 levels(multiplicity comparison)and superiority combination of 5 factors and 2 levels were determined ***:The reinforcing-reducing technique by rotating needle and the supplementary acupoint are the primary factors of therapeutic *** time of rotating needle,treatment interval and time of needle retention were the secondary ***:In the observation of five factors and two levels,the optimal regimen of acupuncture for GERD includes reducing technique by rotating needle at PC 6,the time of rotating needle for 60 s,Zúsānlǐ(足三里 ST 36)and Tàichōng(太冲 LR 3)as the supplementary acupoints,needle retention for 30 min and treatment interval of 24 h.

关键词： Gastroesophageal reflux disease Neiguān(内关PC 6) Orthogonal design Stimulus quantity

Detection of Stage I nasopharyngeal carcinoma by serologicscreening and clinical examination

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Chinese Journal of Cancer 2011年第2期30卷 120-123页

作者： Ming-Fang ji Yuan-Long Yu Wei-Ming Cheng Yong-Sheng Zong Park Sze-Park ng Daniel Tsin-Tien Chua Mun-Hon ng Cancer Research Institute of Zhongshan City Zhongshan Guangdong 528403 P R China Department of Pathology Sun Yat-sen Medical College Sun Yat-sen University Guangzhou Guangdong 510080 P. R. China Department of Microbiology Faculty of Medicine The University of Hong Kong Hong Kong SAR P. R. China Department of Clinical Oncology Faculty of Medicine The University of Hong Kong Hong Kong SAR P. R. China

In a prospective study, 42 048 adults residing in Zhongshan City, Guangdong, China, were followed for 16 years, and 171 of them developed nasopharyngeal carcinoma (NPC). Although Epstein-Barr virus (EBV) antibody levels of the cohort fluctuated, the antibody levels of 93% of the patients with NPC were raised and maintained at high levels for up to 10 years prior to diagnosis. This suggests that the serologic window affords an opportunity to monitor tumor progression during the preclinical stage of NPC development, facilitating early NPC detection. We reviewed the clinical records of the 171 patients with NPC in the prospective study to assess the efficacy of early NPC detection by serologic screening and clinical examination. Of the 171 patients, 51 had Stage I tumor (44 were among the 73 patients detected by clinical examination and 7 were among the 98 patients presented to outpatient department). Initial serologic screening predicted 58 (95.1%) of the 61 patients detected within 2 years. The risk of the screened population (58/3093) raised 13 times relative to cohort (61/42 048) during this period. Clinical examination detected all the 58 predicted cases, and 35 (60.3%) of which were diagnosed with Stage I tumor. The serologic prediction rate fell to 33.6% (37/110) 2 to 16 years after screening. The proportion of cases detected by clinical examination fell to 40.5% (15/37). The proportion of Stage I tumors among the cases detected by clinical examination during both periods remained at about 60%. We concluded that early detection of NPC can be accomplished by repeated serologic screening to maintain high prediction rates and by promptly examining screened subjects to detect tumors before the symptoms develop.

关键词：血清学检测临床检查鼻咽癌筛查一阶全国人民代表大会抗体水平 EB病毒

新型城镇化语境下非物质文化遗产的结构性调整与重建问题研究——非物质文化遗产保护与发展的方法论思考

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青海民族研究 2019年第2期30卷 63-71页

作者：张纪群杨亮山东大学山东济南250000 山东财经大学山东济南250014

在新型城镇化语境下,运用结构主义方法进行'非遗'的保护与发展,是符合我国国情的方法论的思考。传统农耕文明时期,推动'非遗'生产与发展的结构形式是简单而稳固的,而在新型城镇化语境下,由于'非遗'价值体系的瓦解、生活方式的演革、审... 详细信息

在新型城镇化语境下,运用结构主义方法进行'非遗'的保护与发展,是符合我国国情的方法论的思考。传统农耕文明时期,推动'非遗'生产与发展的结构形式是简单而稳固的,而在新型城镇化语境下,由于'非遗'价值体系的瓦解、生活方式的演革、审美习惯的巨变,以及商业化导向等原因,传统的结构形式逐渐消解、瓦解。因此,作为精神家园的'非遗'须进行结构性调整和重建,结构性调整是为了解决传统结构内部出现的矛盾,而重建的则是构建生态、有机与多元的'非遗'结构体系,其目的是为了发掘'非遗'保护与发展的推动力,进而实现文化多样性和保持人类创造性的美好愿望。

关键词：非遗结构主义新型城镇化结构性调整结构性重建

Effects of external temperature and dead volume on laboratory measurements of pore pressure and injected volume in a rock fracture

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Journal of Rock Mechanics and Geotechnical Engineering 2022年第5期14卷 1461-1469页

作者： Yinlin ji Christian Kluge Hannes Hofmann Guido Blöcher Helmholtz Centre Potsdam GFZ German Research Centre for GeosciencesPotsdam14473Germany State Key Laboratory of Coal Resources and Safe Mining China University of Mining and TechnologyXuzhou221116China

The accurate evaluation of pore pressure and injected volume is crucial for the laboratory characterization of hydromechanical responses of rock fractures. This study reports a series of laboratory experiments to systematically demonstrate the effects of external temperature and dead volume on laboratory measurements of pore pressure and injected volume in a rock fracture. We characterize the hydraulic aperture of the fracture as a function of effective normal stress using the exponential aperture *** model is then employed to predict the pore pressure change and injected volume in the fracture without the influences of external temperature and dead volume. The external temperature changes in the cyclic loading test due to the Joule-Thompson effect for fluids. The effect of external temperature on pore pressure change in the fracture can be well explained by thermal pressurization of fluids. Our results also show that the external dead volume can significantly lower the pore pressure change in the fracture during the cyclic loading test under undrained conditions. The injected volume can also be substantially enlarged due to the external dead volume in a typical pore pressure system. Internal measurement of the pore pressure in the fracture using a fiber optic sensor cannot exclude the influences of external temperature and dead volume, primarily because of the good hydraulic communication between the fracture and pore pressure system. This study suggests that the effects of external temperature and dead volume on pore pressure response and injected volume should be evaluated for accurate laboratory characterization and inter-laboratory comparison.

关键词： Fracture aperture Thermal pressurization External dead volume Pressure attenuation Injected volume Fiber optic sensor

民事检察建议的分类重构与原理探寻——以二元化权能结构为背景

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大连理工大学学报（社会科学版） 2015年第1期36卷 131-136页

作者：韩静茹北京大学法学院北京100871

依循民事检察权的二元化权能结构,可以将规范和实践领域形态多样的民事检察建议划分为以执法监督为职能的公权制约型检察建议和以守法监督为职能的社会治理型检察建议两大类,前者由再审检察建议、对审判人员违法行为的检察建议、执行监... 详细信息

依循民事检察权的二元化权能结构,可以将规范和实践领域形态多样的民事检察建议划分为以执法监督为职能的公权制约型检察建议和以守法监督为职能的社会治理型检察建议两大类,前者由再审检察建议、对审判人员违法行为的检察建议、执行监督检察建议组成,后者由督促起诉、申诉中的和解检察建议、执行协助检察建议组成。通过对这六种两类检察建议制度的生发原因、运行现状和主要问题进行梳理,能够提炼出各类检察建议的共性特征和运行原理:其中公权制约型检察建议的构建和运行应当遵循合法性和约束力原则、内部制约机制优先原则、比例原则和谦抑性原则;社会治理型检察建议的构建和运行需要遵循有限性原则、防止角色异化原则、公民自治和社会自治优先原则、合法性与规范性原则。

关键词：民事检察建议公权制约型检察建议社会治理型检察建议类型化运行原理

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游览参观点门票价格管理问题研究

消费经济 2006年第1期22卷 53-56页

作者：熊正德张洁湖南大学工商管理学院

随着旅游业的迅猛发展,游览参观点门票价格管理水平的高低对于各地旅游业有序发展具有重要意义。文章在全面分析游览参观点门票价格及其管理现状的基础上,重点探究了当前游览参观点门票价格管理存在的问题,并提出了若干改进与完善思路。

关键词：游览参观点门票价格听证会价格管理

Mechanical anisotropy associated with beddings in shale under Brazilian test conditions:Insights from acoustic emission statistics

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第11期16卷 4462-4479页

作者： Yongfa Zhang Yinlin ji Yu Zhao Qinglin Deng Chaolin Wang College of Civil Engineering Guizhou UniversityGuiyang550025China Helmholtz Centre Potsdam GFZ German Research Centre for GeosciencesPotsdam14473Germany State Key Laboratory of Coal Mine Disaster Dynamics and Control School of Resource and Safety EngineeringChongqing UniversityChongqing400044China

A comprehensive understanding of shale’s bedding anisotropy is crucial for shale-related engineering activities,such as hydraulic fracturing,drilling and underground *** this study,seven Brazilian tests were conducted on shale samples at different bedding orientations with respect to the loading direction(0°,45°and 90°)and the disc end face(0°,45°and 90°).An acoustic emission(AE)system was employed to capture the evolution of damage and the temporal-spatial distribution of microcracks under splitting-tensile *** results show that the Brazilian tensile strength decreases with increasing bedding inclination with respect to the disc end face,while it increases with the angle between bedding and loading *** the bedding inclination with respect to the end face facilitates the reduction in b value and enhances the shale’s resistance to microcrack growth during the loading *** between the bedding orientation and the end face suppresses the growth of mixed tensile-shear microcracks,while reducing the bedding angle relative to the loading direction is beneficial for creating mixed tensile-shear and tensile *** observed microscopic failure characteristics are attributed to the competing effects of bedding activation and breakage of shale matrix at different bedding *** temporal-spatial distribution of microcracks,characterized by AE statistics including the correlation dimension and spatial correlation length,illustrates that the fractal evolution of microcracks is independent of bedding anisotropy,whereas the spatial distribution shows a stronger *** evolution features of correlation dimension and spatial correlation length could be potentially used as precursors for shale splitting *** findings may be useful for predicting rock mass instability and analyzing the causes of catastrophic rupture.

关键词： Bedding anisotropy Acoustic emission(AE) Shale Brazilian test Rock failure mechanism Splitting-tensile cracks