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Disclination and molecular director studies on bowlic columnar nematic phase using mosaic-like morphologydecoration method

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Science China Chemistry 2009年第7期52卷 986-999页

作者： DONG YanMing CHEN DanMei ZENG ErMan hu xiaolan ZENG ZhiQun Department of Materials Science and Engineering College of MaterialsXiamen UniversityXiamen 361005China

Two bowlic cyclotriveratrylene CTV-1 and CTV-2, with different peripheral groups of -OCH3 and -OCH2CH3 for CTV-1 and -OCH3 and -OCH2COOCH3 for CTV-2, respectively, were synthesized by typical trimerization via a multistep sequence from vanillin. Both bowlic CTV molecules were thermotropic liquid crystals, and presented typical grainy textures of the nematic phase and homogeneous texture of the single domain nematic phase. It is of interest to observe the regular and beautiful mosaic-like morphologies after cooling from liquid crystalline phases, which appeared and vanished repeatedly in several circles of cooling and heating. The size of each mosaic was several dozens of micron. In nature, the mosaic-like morphologies are the optical pattern of cracks formed by the shrinking, due to the crystallization of frozen texture of nematic phases. By means of scanning electron microscopy, the mosaic-like morphologies were observed to consist of lamellae, and each mosaic is a rectangular multi-layer lamella, which is composed of packed single-layered lamellae. The fibrils in the diameter of about 1 μm were observed, which are the structural units of lamellae and would be the bundles of the bowlic molecular columns. The mosaic-like morphologies decorate the bowlic molecular columnar nematic phase, therefore, a novel mosaic-like morphologies decoration method was applied to reveal the director distribution of several kinds of point disclinations, such as s = +1(δ =0°and δ =90°) and s = ±1/2, and Nèel domain walls. It was shown that the bowlic molecular columnar nematic phase behaved as normal nematic phases; however, the basic structural units ordered were the bowlic molecular column or the bundles of bowlic molecular column (i.e. fibrils), but not the bowlic molecules themselves. The bowlic molecular columns acted as the rod-like molecules in a normal nematic phase. Therefore, a new term BCN (bowlic columnar nematic phase) is used to describe the anomalous nematic phase in thi

关键词： CTV bowlic molecules thermotropic liquid crystals bowlic columnar nematic phase BCN mosaic-like morphologies disclination

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Novel chitosan-ethylene glycol hydrogel for the removal of aqueous perfluorooctanoic acid

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Journal of Environmental Sciences 2019年第10期31卷 21-28页

作者： Li Long xiaolan hu Jinpeng Yan Yifan Zeng Jiaqi Zhang Yingwen Xue School of Civil Engineering Wuhan University

It is urgent to explore an effective removal method for perfluorooctanoic acid(PFOA)due to its recalcitrant *** this study,a novel chitosan-based hydrogel(CEGH)was prepared with a simple method using chitosan and ethylene glycol through a repeated freezingthawing *** adsorption of PFOA anions to CEGH agreed well to the FreundlichLangmuir model with a maximum adsorption capacity as high as 1275.9 mg/g,which is higher than reported values of most adsorbents for *** adsorption was influenced by experimental *** results showed that the main removal mechanism was the ionic hydrogen bond interaction between carbonyl groups(COO-)of PFOA and protonated amine(NH^+)of the CEGH ***,CEGH is a very attractive adsorbent that can be used to remove PFOA from water in the future.

关键词： PFOA removal Chitosan-based material Hydrogel Adsorption mechanism

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Carbon and Oxygen Isotopic Compositions: How Lacustrine Environmental Factors Respond in Northwestern and Northeastern China

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Acta Geologica Sinica(English Edition) 2013年第5期87卷 1344-1354页

作者： ZHANG Chengjun FAN Rong LI Jun Steffen MISCHKE laise DEMBELE hu xiaolan School of Earth Sciences&Key Laboratory of Mineral Resources in Western China (Gansu Province) Lanzhou University College of Resource and Environmental Sciences Lanzhou University Institute of Earth and Environmental Science University of Potsdam

Surface lake sediments, 28 from Hoh XU, 24 from northeastern China, 99 from Lake Bosten, 31 from Ulungur and 26 from Heihai were collected to determine δ13C and δ18O values. Considering the impact factors, conductivity, alkalinity, pH, TOC, C/N and carbonate-content in the sediments, CI, P, S, and metal element ratios of Mg/Ca, Sr/Ca, Fe/Mn of bulk sediments as environmental variables enable evaluation of their influences on δ13C and δ18O using principal component analysis （PCA） method. The closure and residence time of lakes can influence the correlation between δ13C and δ18O. Lake water will change from fresh to brackish with increasing reduction and eutrophication effects. Mg/Ca in the bulk sediment indicates the characteristic of residence time, Sr/Ca and Fe/Mn infer the salinity of lakes. Carbonate formation processes and types can influence the 6~3C--~1So correlation. ~180 will be heavier from Mg-calcite and aragonite formed in a high-salinity water body than calcite formed in freshwater conditions. When carbonate content is less than 30%, there is no relationship with either 613C or 6180, and also none between δ13C and δ18O. More than 30%, carbonate content, however, co-varies highly to δ13C and δ18O, and there is also a high correlation between δ13C and δ18O. Vegetation conditions and primary productivity of lakes can influence the characteristics of δ13C and δ18O, and their co-variance. Total organic matter content （TOC） in the sediments is higher with more terrestrial and submerged plants infilling. In northeastern and northwestern China, when organic matter in the lake sediments comes from endogenous floating organisms and algae, the δ13C value is high. δ13C is in the range of-4‰ to 0‰ when organic matter comes mainly from floating organisms （C/N〈6）; in the range of-4‰ to 8‰ when organic matter comes from diatoms （C/N=6 to 8）; and -8‰ to -4‰ when organic matter comes from aquatic and terrestrial plants （C/N〉8）.

关键词： Limnology isotopic analysis carbonates organic matter PCA Tibet Xinjiang,Northeastern China

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Characteristics of Abnormal Pressure Systems and Their Responses of Fluid in huatugou Oil Field,Qaidam Basin

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Acta Geologica Sinica(English Edition) 2009年第5期83卷 939-950页

作者： CHEN Xiaozhi XU Hao TANG Dazhen ZHANG Junfeng hu xiaolan TAO Shu CAI Yidong School of Energy Resources China University of Geosciences Beijing 100083 China Key Laboratory of Marine Reservoir Evolution and Hydrocarbon Accumulation Mechanism Ministry ofEducation China University of Geosciences Beijing 100083 China PetroChina Exploration and Production Company Beijing 100724 China

Based on the comprehensive study of core samples, well testing data, and reservoir fluid properties, the construction and the distribution of the abnormal pressure systems of the huatugou oil field in Qaidam Basin are discussed. The correlation between the pressure systems and hydrocarbon accumulation is addressed by analyzing the corresponding fluid characteristics. The results show that the huatugou oil field as a whole has low formation pressure and low fluid energy; therefore, the hydrocarbons are hard to migrate, which facilitates the forming of primary reservoirs. The study reservoirs, located at the Xiayoushashan Formation （N1/2） and the Shangganchaigou Formation （N1） are relatively shallow and have medium porosity and low permeability. They are abnormal low-pressure reservoirs with an average formation pressure coefficient of 0.61 and 0.72 respectively. According to the pressure coefficient and geothermal anomaly, the N1 and N1/2 Formations belong to two independent temperature-pressure systems, and the former has slightly higher energy. The low-pressure compartments consist of a distal bar as the main body, prodelta mud as the top boundary, and shore and shallow lake mud or algal mound as the bottom boundary. They are vertically overlapped and horizontally paralleled. The formation water is abundant in the Cl^- ion and can be categorized as CaCl2 type with high safinity, which indicates that the abnormal low-pressure compartments are in good sealing condition and beneficial for oil and gas accumulation and preservation.

关键词： abnormal pressure system low-pressure compartment fluid characteristics huatugou oil field Qaidam basin

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Combination Patterns and Depositional Characteristics of Ordovician Carbonate Banks in the Western Tarim Basin,China

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Acta Geologica Sinica(English Edition) 2012年第4期86卷 894-911页

作者： hu xiaolan FAN Tailiang GAO Zhiqian YU Bingsong CHEN Xiaozhi WANG Hongyu WANG Jianping LI Rangbin DING Meng LI Yifan School of Energy Resources China University of Geosciences Key Laboratory of Marine Reservoir Evolution and Hydrocarbon Accumulation Mechanism Ministry of EducationChina University of Geosciences State Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences CNOOC Research Institute

The combination patterns and depositional characteristics of the carbonate banks are investigated based on outcrop sections, thin sections, and carbon isotopes of Ordovician in the western Tarim Basin, China. Four carbonate bank combination patterns are deposited in the Ordovician, western Tarim Basin, including： Reef-Bank Complex （RBC）, Algae-Reef-Bank Interbed （ARBI）, Thick-Layer Cake Aggradation Bank （TLCAB）, and Thin-Layer Cake Retrogradation Bank （TLCRB）. All combination patterns show clear periods vertically. The RBC is mainly composed of reefs and bioclastic banks, and the dimension of the RBC depends on the scale of the reefs. Bioclastic banks deposits surround the reefs. The range of the ARBI is determined by the scale of algae-reefs, algae peloid dolomite microfacies and algal dolomite microfacies deposit alternating vertically. TLCAB and TLCRB are deposited as layer-cakes stacking in cycles and extending widely with cross bedding developed. The grains of TLCAB and TLCRB are diverse and multi-source. With the impacting of relative sea level change, biological development and geomorphology, the ARBI, TLCAB or TLCRB, RBC are successively developed from the Lower Ordovician Penglaiba Formation to the Middle Ordovician Yijianfang Formation. The depositional environment analysis of Ordovician indicates that the RBC and ARBI can form effective oil and gas reservoirs, and the TLCAB and TLCRB have the potential to form the huge scale oil and gas reservoirs and to be the crucial targets of exploration for the Ordovician carbonate banks in the future.

关键词： Carbonate bank reef-bank complex algae-reef-bank interbed thick-layer cake aggradation bank thin-layer cake retrogradation bank Ordovician western Tarim Basin

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硫酸钙晶须改性双马来酰亚胺树脂摩擦磨损性能的研究

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高分子学报 2006年第5期16卷 686-691页

作者：胡晓兰余谋发厦门大学化学化工学院材料科学与工程系厦门361005

研究了载荷、偶联剂及硫酸钙晶须用量对双马来酰亚胺树脂摩擦磨损性能的影响及材料的磨损机制.结果表明,当摩擦载荷较大时,树脂基体在摩擦过程中出现明显的塑性变形和裂纹,而经过硫酸钙晶须改性的复合材料体系则塑性变形和裂纹情况得到... 详细信息

研究了载荷、偶联剂及硫酸钙晶须用量对双马来酰亚胺树脂摩擦磨损性能的影响及材料的磨损机制.结果表明,当摩擦载荷较大时,树脂基体在摩擦过程中出现明显的塑性变形和裂纹,而经过硫酸钙晶须改性的复合材料体系则塑性变形和裂纹情况得到明显的改善,并且磨损量显著降低.载荷从200 N增大到300 N后,树脂基体的磨损机制从粘着磨损过渡为严重的疲劳磨损,添加晶须体系仍以粘着磨损为主.晶须添加量较小时,复合材料的磨损机理主要为粘着磨损,晶须添加量较高时,磨粒磨损占主导地位.

关键词：双马来酰亚胺树脂硫酸钙晶须摩擦磨损

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废气中一氧化氮检测能力验证结果探究

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理化检验（化学分册） 2024年第8期60卷 841-845页

作者：胡晓兰上海市环境监测中心上海200235

氮氧化物是我国严格监控的污染物之一,大气中的氮氧化物主要以一氧化氮(NO)和二氧化氮(NO2)的形式存在,它们主要来自石油产品和煤的燃烧产物、汽车尾气以及制硝酸工厂的废气等^([1])。NO为无色、无臭、微溶于水的气体,很不稳定,在空气... 详细信息

氮氧化物是我国严格监控的污染物之一,大气中的氮氧化物主要以一氧化氮(NO)和二氧化氮(NO2)的形式存在,它们主要来自石油产品和煤的燃烧产物、汽车尾气以及制硝酸工厂的废气等^([1])。NO为无色、无臭、微溶于水的气体,很不稳定,在空气中会很快转变为NO2从而产生刺激作用,是电力、建材、冶金、化工、城市公共事业(垃圾和危险废物焚烧)等行业普遍要求控制和监测的污染物。

关键词：氮氧化物汽车尾气危险废物焚烧刺激作用 NO2 废气

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医疗工作者膳食补充剂服用情况及认知现况调查

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中国食品卫生杂志 2023年第5期35卷 699-705页

作者：黄婷婷胡晓岚黄石市疾病预防控制中心湖北黄石435005 武汉科技大学职业危害识别与控制湖北省重点实验室湖北武汉430065 黄石市中心医院/湖北理工学院附属医院医联体办公室湖北黄石435000

目的探究疫情防控常态化下医疗工作者的膳食补充剂使用及认知情况,为医疗工作者营养支持提供思路。方法采用方便抽样调查的方式面向2021年1—4月在鄂东医疗集团就职、参与抗击新型冠状病毒疫情的医疗工作者发放调查问卷,将回收的188份... 详细信息

目的探究疫情防控常态化下医疗工作者的膳食补充剂使用及认知情况,为医疗工作者营养支持提供思路。方法采用方便抽样调查的方式面向2021年1—4月在鄂东医疗集团就职、参与抗击新型冠状病毒疫情的医疗工作者发放调查问卷,将回收的188份电子问卷数据采用SPSS 22.0软件进行统计分析。结果医疗工作者总体膳食补充剂服用率为22.34%(42/188),文化程度越高、从未饮酒者的膳食补充剂服用率均显著高于文化程度低、饮酒者(P0.05);在认知态度上,服用人群在“膳食补充剂是安全的”“、膳食补充剂具有一定的健康作用”“、与药品有交互作用”这3条观点上明显持同意的态度(P<0.05)。医疗工作者主要服用的膳食补充剂前三位为复合型维生素矿物质制剂(59.52%)、单一维生素制剂(57.14%)及蛋白粉(40.48%)。Logistic回归分析结果显示,影响医疗工作者膳食补充剂服用的影响因素主要是文化程度(OR=7.314)和认为膳食补充剂是安全的支持态度上(OR=0.098)。结论医疗工作者膳食补充剂的服用率较低,建议在疫情防控常态化下,开展膳食补充剂相关健康宣传教育工作,确保医疗工作者的健康状况。

关键词：医疗工作者膳食补充剂新冠疫情服用率认知情况

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先锋作家的“出城”记——从《文城》看余华创作的再转型

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南方文坛 2021年第6期 182-186页

作者：孟觉之胡小兰复旦大学中文系江西师范大学文学院

翻阅余华的长篇新作《文城》,扑面而来的仍是熟悉的气息:叙事背景中依旧隐现着暴力、刑罚、罪恶、阴谋、死亡等交织成的艺术图景;叙事题旨上仍然牵涉着时空乱象的揭示与生存本相的追问,生命个体的悲苦命运、坚韧追寻与温情守望;叙事风... 详细信息

翻阅余华的长篇新作《文城》,扑面而来的仍是熟悉的气息:叙事背景中依旧隐现着暴力、刑罚、罪恶、阴谋、死亡等交织成的艺术图景;叙事题旨上仍然牵涉着时空乱象的揭示与生存本相的追问,生命个体的悲苦命运、坚韧追寻与温情守望;叙事风格上再度延续着重复式的诗学、怪诞性的笔触和暴力化的美学。

关键词：先锋作家余华叙事风格怪诞性生存本相生命个体暴力化文城

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The approaches in detecting cell cycle specificity of Fas-mediated apoptosis in leukemia cell lines and activated PBLs in vitro

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The Chinese-German Journal of Clinical Oncology 2006年第5期5卷 379-382页

作者： Xiaojun He Jing hu xiaolan Li hui Xiao Deding Tao Haocheng Long Jianping Gong Tongji Cancer Research Institute/Molecular Medical Center Tongji Hopital Tongji Medical College Huazhong University of Science and Technology Wuhan 430030 China

Objective： To establish a system in detecting the cell cycle specificity induced by recombinant human Fas ligand in vitro, so as to provide a reliable platform for further exploring the mechanism of cell cycle control and regulation in Fas-mediated apoptosis. Methods： The target cells-leukaemia cell lines and activated peripheral blood lymphocytes stimulated by phytohemagglutinin were incubated with recombinant human Fas ligand for 6 to 36 h, apoptosis was detected by sub-G1, common annexin-Ⅴ/PI and modified annexin Ⅴ and propidium iodide （API） methods and analysed by flow cytometry. Results： The modified API method demonstrated that Fas-mediated apoptosis was cell cycle specific and initiated at G1 phase. The common annexinⅤ/PI method showed the most appropriate condition for the detection of typical cell cycle-specific apoptosis. The sub-G1 method could only illuminate late apoptosis and DNA histogram. Conclusion： Fas-mediated apoptosis was cell cycle-specific and initiated at G 1 phase. Based on the modified API and common AnnexinⅤ/PI methods, the establishment of stable and typical cell cycle-specific model in Fas-mediated apoptosis in vitro was feasible.

关键词： Fas-mediated apoptosis cell cycle flow cytometry leukaemia cell peripheral blood lymphocyte

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