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Chinese Journal of Polymer Science 2024年第3期42卷 364-372,I0008页

作者： Jia-Shu Ma Zhi-ning Huang Jia-Hao Li Bang-ping Jiang Yan-Da Liao Shi-Chen Ji Xing-Can Shen State Key Laboratory for Chemistry and Molecular Engineering of Medicinal Resources Key Laboratory for Chemistry and Molecular Engineering of Medicinal Resources(Ministry of Education of China)School of Chemistry and Pharmaceutical SciencesGuangxi Normal UniversityGuilin 541004China School of Computer Science and Engineering&School of Software Guangxi Normal UniversityGuilin 541004China

To better characterize the properties of surface-initiated polymers, simultaneous bulk-and surface-initiated polymerizations are usually carried out by assuming that the properties of the surface-initiated polymers resemble those of the bulk-initiated polymers. Through a Monte Carlo simulation using a heterogeneous stochastic reaction model, it was discovered that the bulk-initiated polymers exhibit a higher molecular weight and a lower dispersity than the corresponding surface-initiated polymers, which indicates that the equivalent assumption is invalid. Furthermore, the molecular weight distributions of the two types of polymers are also different, suggesting different polymerization mechanisms. The results can be simply explained by the heterogeneous distributions of reactants in the system. This study is helpful to better understand surface-initiated polymerization.

关键词： Surface-initiated polymerization Polymer brush Stochastic reaction model Heterogeneous polymerization Simultaneous polymerization

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荔枝花蜜腺的结构发育特点及其生物学意义

植物分类学报 2006年第5期44卷 523-537页

作者：宁熙平吴鸿华南农业大学药用植物研究中心广州510642

荔枝Litchichinensis花蜜腺通过分泌蜜汁吸引传粉昆虫。蜜腺的结构和大小决定了蜜汁的数量和浓度,后两者又必然影响昆虫的访花模式。本文研究了“糯米糍”和“妃子笑”荔枝花蜜腺的结构和发育特点。两个品种的雌、雄性功能花花蜜腺都位... 详细信息

荔枝Litchichinensis花蜜腺通过分泌蜜汁吸引传粉昆虫。蜜腺的结构和大小决定了蜜汁的数量和浓度,后两者又必然影响昆虫的访花模式。本文研究了“糯米糍”和“妃子笑”荔枝花蜜腺的结构和发育特点。两个品种的雌、雄性功能花花蜜腺都位于杯状的花萼和具柄的子房之间及花丝周围的花托表面,向上隆起,形成发达突起的花盘蜜腺。成熟蜜腺结构上包含表皮、泌蜜组织和仅由韧皮部构成的维管组织,属于典型的结构蜜腺。蜜腺表皮具多数发达角质化细胞壁的单细胞表皮毛,表皮细胞外切向壁具厚的角质层。蜜腺顶端区具少数小的气孔器。泌蜜前,泌蜜组织细胞具大量的淀粉,且在泌蜜前后表现出动态的消长变化。泌蜜组织中具有两种不同形态特征的细胞分化,推测其分别与蜜汁的合成和蜜腺组织损伤褐变的保护功能有关。雌、雄性功能花花蜜腺都是在花的其他结构基本分化完成后才开始分化发育的,蜜腺的发育与大、小孢子的发育具有一定的协同性和相关性。依据蜜腺分化和发育过程的特征,对荔枝花蜜腺在起源和系统发育上的特点进行了探讨。

关键词：荔枝花蜜腺形态发育传粉

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南开大学奇异性核物理的理论研究(英文)

高能物理与核物理 2007年第9期31卷 864-869页

作者：宁平治南开大学物理科学学院天津300071

简要介绍了南开大学核物理组在奇异性核物理方面的理论研究工作.已经完成的工作有核介质内超子平均自由程的理论计算,奇异性核物理方面已完成的其他4个理论研究课题是,不同重子杂质对原子核的影响、重味重子超核、核物质内的eta-介子以... 详细信息

简要介绍了南开大学核物理组在奇异性核物理方面的理论研究工作.已经完成的工作有核介质内超子平均自由程的理论计算,奇异性核物理方面已完成的其他4个理论研究课题是,不同重子杂质对原子核的影响、重味重子超核、核物质内的eta-介子以及K介子原子核的性质.

关键词：核物理奇异性超子

Particle-bound polycyclic aromatic hydrocarbons in typical urban of Yunnan-Guizhou Plateau:Characterization,sources and risk assessment

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Frontiers of Environmental Science & Engineering 2022年第9期16卷 25-38页

作者： Yaoqian Zhong Bingxin Xia Jianwu Shi ping ning Chaoneng Zhang Xinyu Han Jiming Hao Faculty of Environmental Science and Engineering Kunming University of Science and TechnologyKunming 650500China State Key Joint Laboratory of Environmental Simulation and Pollution Control School of EnvironmentTsinghua UniversityBeijing 100084China

Monthly particle-phase ambient samples collected at six sampling locations in Yuxi,a high-altitude city on the edge of Southeast Asia,were measured for particle-associated *** trace substances,polycyclic aromatic hydrocarbons(PAHs)are susceptible to the influences of meteorological conditions,emissions,and gas-particulate partitioning and it is challenging job to precise quantify the source and define the transmission *** daily concentrations of total PM_(2.5)-bound PAHs ranged from 0.65 to 80.76 ng/m^(3),with an annual mean of 11.94 ng/m^(3).Here,we found that the concentration of PM_(2.5)-bound PAHs in winter was significantly higher than that in summer,which was mainly due to source and meteorology *** increase of fossil combustion and biomass burning in cold season became the main contributors of PAHs,while precipitation and low temperature exacerbated this *** to the concentration variation trend of PM_(2.5)-bound PAHs and their relationship with meteorological conditions,a new grouping of PAHs is applied,which suggested that PAHs have different environmental fates and migration paths.A combination of source analysis and trajectory model supported local sources from combustion of fossil fuel and vehicle exhaust contributed to the major portion on PAHs in particle,but on the Indochina Peninsula the large number of pollutants emitted by biomass burning during the fire season would affect the composition of PAHs through long-range *** assessment in spatial and temporal variability suggested that citizens living in industrial areas were higher health risk caused by exposure the PM_(2.5)-bound PAHs than that in other regions,and the risk in winter was three times than in summer.

关键词： Particle-associated PAHs Fine particle Source appointment Group analysis Risk assessment Biomass burning

Phosphatase and tensin homolog gene inhibits the effect induced by gonadotropin-releasing hormone subtypes in human endometrial carcinoma cells

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Chinese Medical Journal 2010年第9期123卷 1170-1175页

作者： ZHAO Li-jun LIU ning LI Xiao-ping WANG Jian-liu WEI Li-hui Department of Obstetrics & Gynecology Peking University People's Hospital100044BeijingChina

Background Type I gonadotropin-releasing hormone （GnRH-l） agonists have been applied for the treatment of steroid-dependent tumors such as breast carcinoma, ovarian cancer and prostatic carcinoma. But the mechanism has not been clarified yet. There are few reports about the treatment of endometrial carcinoma using GnRH-l agonists. Type II GnRH （GnRH-ll） is a new subtype of GnRH. Our aim was to investigate the effects of GnRH-l agonists and GnRH-ll on estrogen receptor-negative human endometrial carcinoma cells and the effect from phosphatase and tensin homolog gene （PTEN） to *** A lentiviral vector-mediated RNAi method was used to establish a PTEN-negative HEC-1A cell clone （HEC-1A-ND）. MTT and flow cytometry were used to detect the cell proliferation, cell cycle and apoptosis of HEC-1A, HEC-1A-NC and HEC-1A-ND cells after treatment with GnRH-l agonist Triptorelin （10-11 mol/L to 10-5 mol/L） or GnRH-ll （10-11 mol/L to 10-5 mol/L）. Western blotting was used to detect AKT and ERK1/2 activation after treatment with different concentrations of Triptorelin or GnRH-ll for 30 minutes in the above mentioned three kinds of cells. Results Triptorelin and GnRH-ll induced apoptosis and inhibited proliferation of HEC-1 A, HEC-1A-ND and HEC-1A-NC in a dose-dependent manner. This effect was augmented in HEC-1 A-ND cells in which PTEN gene was knocked-down. Furthermore, Triptorelin and GnRH-ll inhibited the AKT and ERK activity in HEC-1 A-ND *** Triptorelin and GnRH-ll can promote apoptosis rate and inhibit cell proliferation of estrogen receptor-negative endometrial carcinoma cells in a dose-dependent manner. PTEN gene can inhibit the effects of Triptorelin or GnRH-ll on human endometrial carcinoma cells.

关键词： human endometrial carcinoma gonadotropin-releasing hormone-I agonist estrogen receptor

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浸渍活性炭吸附低浓度PH_3动力学

中南大学学报（自然科学版） 2011年第7期42卷 2162-2166页

作者：王学谦宁平昆明理工大学环境科学与工程学院云南昆明650093

采用浸渍活性炭吸附净化低浓度磷化氢,研究气相中磷化氢在浸渍活性炭上的吸附平衡和吸附动力学过程。不同温度下的吸附等温线实验测定结果表明：PH3在20~40℃的低温范围内属物理吸附,而在60~95℃的高温范围内属化学吸附,磷化氢在浸渍活... 详细信息

采用浸渍活性炭吸附净化低浓度磷化氢,研究气相中磷化氢在浸渍活性炭上的吸附平衡和吸附动力学过程。不同温度下的吸附等温线实验测定结果表明：PH3在20~40℃的低温范围内属物理吸附,而在60~95℃的高温范围内属化学吸附,磷化氢在浸渍活性炭上的吸附平衡关系符合Freundlich方程;通过对吸附速率曲线拟合可以得到理想的吸附速率方程,氧体积分数为1%的微氧条件下低浓度磷化氢在浸渍活性炭上的吸附动力学行为遵循班厄姆动力学方程。

关键词：活性炭磷化氢吸附等温线吸附动力学

活性炭法净化黄磷尾气中硫化氢、磷化氢的研究进展

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现代化工 2006年第11期26卷 25-28页

作者：任占冬陈 宁平武汉工业学院化学与环境工程系湖北武汉430023 昆明理工大学环境科学与工程系云南昆明650224

综述了活性炭、负载活性炭吸附净化H2S和PH3的研究进展。介绍了作者所在课题组利用催化氧化原理,以活性炭为载体、用浸渍法制备的JC系列催化剂对黄磷尾气中H2S、PH3的深度脱除效果,净化后二者质量浓度均小于1 mg/m3。最后,指出应加强利... 详细信息

综述了活性炭、负载活性炭吸附净化H2S和PH3的研究进展。介绍了作者所在课题组利用催化氧化原理,以活性炭为载体、用浸渍法制备的JC系列催化剂对黄磷尾气中H2S、PH3的深度脱除效果,净化后二者质量浓度均小于1 mg/m3。最后,指出应加强利用负载活性炭净化黄磷尾气的理论研究。

关键词：黄磷尾气磷化氢硫化氢活性炭催化氧化法

Supramolecular polymer-based gel fracturing fluid with a double network applied in ultra-deep hydraulic fracturing

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Petroleum Science 2024年第3期21卷 1875-1888页

作者： Yong-ping Huang Yong Hu Chang-Long Liu Yi-ning Wu Chen-Wei Zou Li-Yuan Zhang Ming-Wei Zhao Cai-Li Dai School of Petroleum Engineering China University of Petroleum(East China)Qingdao266580ShandongPR China Shandong Key Laboratory of Oilfield Chemistry China University of Petroleum(East China)Qingdao 266580ShandongPR China SINOPEC Petroleum Exploration and Production Research Institute Beijing102206PR China CNOOC China Co Ltd Tianjin BranchTianjin300459PR China

A gel based on polyacrylamide,exhibiting delayed crosslinking characteristics,emerges as the preferred solution for mitigating degradation under conditions of high temperature and extended shear in ultralong *** viscosity/viscoelasticity of the fracturing fluid was required to maintain excellent proppant suspension properties before *** into account both the cost and the potential damage to reservoirs,polymers with lower concentrations and molecular weights are generally *** this work,the supramolecular action was integrated into the polymer,resulting in significant increases in the viscosity and viscoelasticity of the synthesized supramolecular polymer *** double network gel,which is formed by the combination of the supramolecular polymer system and a small quantity of Zr-crosslinker,effectively resists temperature while minimizing permeability damage to the *** results indicate that the supramolecular polymer system with a molecular weight of(268—380)×10^(4)g/mol can achieve the same viscosity and viscoelasticity at 0.4 wt%due to the supramolecular interaction between polymers,compared to the 0.6 wt%traditional polymer(hydrolyzed polyacrylamide,molecular weight of 1078×10^(4)g/mol).The supramolecular polymer system possessed excellent proppant suspension properties with a 0.55 cm/min sedimentation rate at 0.4 wt%,whereas the0.6 wt%traditional polymer had a rate of 0.57 cm/*** comparison to the traditional gel with a Zrcrosslinker concentration of 0.6 wt%and an elastic modulus of 7.77 Pa,the double network gel with a higher elastic modulus(9.00 Pa)could be formed only at 0.1 wt%Zr-crosslinker,which greatly reduced the amount of residue of the fluid after *** viscosity of the double network gel was66 m Pa s after 2 h shearing,whereas the traditional gel only reached 27 m Pa s.

关键词： Ultra-deep reservoir Gel fracturing fluid Double network Supramolecular polymer system Proppant suspension property

基于EP9-A3文件对两仪器测定血清甲胎蛋白、癌胚抗原结果的可比性评价

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医学信息 2024年第5期37卷 138-142页

作者：宁萍王雪婷李奋荣何静徐小婕王红红云发超乌鲁木齐市中医医院检验科新疆军区总医院中西医结合科

目的探讨甲胎蛋白(AFP)、癌胚抗原(CEA)在2检测系统上测定结果的可比性。方法以罗氏cobas e 601全自动化学发光免疫分析仪为参比方法(X)，透景Tesmi F4000全自动流式荧光发光免疫分析仪作待测方法(Y),选择待测方法(Y)的检测线性内样本... 详细信息

目的探讨甲胎蛋白(AFP)、癌胚抗原(CEA)在2检测系统上测定结果的可比性。方法以罗氏cobas e 601全自动化学发光免疫分析仪为参比方法(X)，透景Tesmi F4000全自动流式荧光发光免疫分析仪作待测方法(Y),选择待测方法(Y)的检测线性内样本(AFP、CEA各40例)在两仪器上测定。根据美国临床和实验室标准化协会(CLSI)的EP9-A3文件，以1/2TEa(TEa为国家卫生健康委临床检验中心室间质量评审允许总误差)为评判标准，对检测结果进行方法比对、偏倚评估及临床可接受程度分析。结果两仪器所测AFP、CEA结果无统计学意义(P>0.05),计算所得偏倚均在允许误差范围内(均≤12.5%)，线性回归方程的相关性良好(r2>0.95)，在医学决定水平处的偏倚为临床可接受。结论在透景流式荧光发光检测系统测定范围内，AFP和CEA在两个仪器中的检测结果呈显著相关，二者在两个医学决定水平上的相对偏差在临床可接受水平之内，即两台检测仪器间的测定果可比性良好，各级医疗机构可据此来选择合适的仪器。

关键词： EP9-A3 甲胎蛋白癌胚抗原测定方法偏倚评估

Introduction manner of sulfate acid for improving the performance of SO_4^(2–)/CeO_2 on selective catalytic reduction of NO by NH_3

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Journal of Rare Earths 2016年第7期34卷 667-674页

作者：宋忠贤张秋林宁平刘昕樊洁黄真真 Faculty of Environmental Science and Engineering Kunming University of Science and Technology College of Environmental Science and Engineering Hunan University

A series of sulfated CeO2 catalysts were synthesized by impregnation and sol-gel methods and used for selective catalytic reduction （SCR） of NOx by NH3. The results showed that the sulfated CeO2 catalysts prepared by sol-gel method showed excellent catalytic activity at 150-50 ℃, and more than 90% NOx conversion was obtained at 232-450 ℃ with a gas hourly space velocity of 60000 h-1. The catalysts were characterized by X-ray diffraction （XRD）, N2 adsorption, Raman, thermogravimetry （TG）, H2-tem- perature-programmed reduction （H2-TPR） and Py-infrared spectroscopy （Py-IR）. The excellent SCR performance was associated with the surface acidity and the micro-structure. The introduction of sulfate acid into CeO2 could increase the amount of BrOnsted and Lewis acid sites over the catalysts, resulting in the improvement of the low temperature activity. The sulfated CeO2 catalysts prepared by sol-gel method possessed lower crystallization degree, excellent redox property and larger specific surface areas, which were responsible for the superior SCR performance.

关键词： sulfated CeO2 selective catalytic reduction surface acidity micro-structure rare earthsO