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Effect of Olefin-based Compatibilizers on the Formation of Cocontinuous Structure in Immiscible HDPE/iPP Blends

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Chinese Journal of Polymer Science 2020年第11期38卷 1248-1257,I0008页

作者： Fei Yang Li Pan Hui-zhen du Zhe Ma Yue-Sheng Li Tianjin Key Laboratory of Composite and Functional Materials and School of Materials Science and EngineeringTianjin UniversityTianjin 300072China Collaborative Innovation Center of Chemical Science and Engineering(Tianjin) Tianjin 300072China

In this work,the formation of cocontinuous structure in immiscible high density polyethylene/isotactic polypropylene(HDPE/iPP)blends was investigated for various olefin-based compatibilizers of distinct molecular architectures,including ternary random copolymer EPDM,olefin block copolymer(OBC),polypropylene-based OBC(PP-OBC),ethylene/a-olefin copolymer(POE),bottlebrush polymer poly(1-dodecene),and comb-like poly(propylene-co-high a-olefin)(PPO).The scanning electron microscopy results show that after adding OBC,PP-OBC,and POE copolymers,the finer droplet-in-matrix morphologies were obtained in 70/30 HDPE/iPP ***,for 70/30 HDPE/iPP blend with just 5 wt%of PPO copolymers,the phase inversion from droplet-in-matrix to cocontinuous morphology can be *** was proposed that the development of cocontinuous morphology contained the following steps:(1)in terfacial saturati on of compatibilizers and droplet deformation,(2)droplet-droplet coalesce nee,(3)continuity development,and(4)the formation of dual-phase con *** the diverse copolymers studied in this work,PPO copolymer can be easily removed out of the interface during droplet coalescence and stabilize the curvature of minor fiber phase,facilitating the formation of cocontinuous *** contrast,other olefin-based compatibilizers(EPDM,OBC,PP-OBC,and POE)exhibit the distinct steric repulsion effect to prohibit droplet ***,the cocontinous interval varies with the compatibilizer ***,after adding 10 wt%of PPO copolymers,the cocontinuous interval was greatly broadened from HDPE/iPP range of 45/55-60/40 to that of 40/60-70/30.

关键词： Compatibilizer Polyolefin Cocontinuous structure Droplet-coalescence Phase inversion

Benzylic aroylation of toluenes with unactivated tertiary benzamides promoted by directed ortho-lithiation

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Science China Chemistry 2021年第8期64卷 1349-1354页

作者： Can-Can Bao Yan-Long Luo Hui-zhen du Bing-Tao Guan College of Chemistry Nankai UniversityTianjin300071China Department of Chemistry Fudan UniversityShanghai200438China

The deprotonative functionalization of toluenes,for their weak acidity,generally needs strong bases,thus leading to the requirement of harsh conditions and the generation of *** nucleophilic acyl substitution reaction of amides with organometallic reagents could provide an ideal solution for ketone ***,the inert amides and highly reactive organometallic reagents bring great challenges for an efficient and selective synthetic ***,we reported an lithium diisopropylamide(LDA)-promoted benzylic aroylation of toluenes with unactivated tertiary benzamides,providing a direct and efficient synthesis of various aryl benzyl *** process features a kinetic deprotonative functionalization of toluenes with a readily available base *** studies revealed that the directed ortho-lithiation of the tertiary benzamide with LDA promoted the benzylic kinetic deprotonation of toluene and triggered the nucleophilic acyl substitution reaction with the amide.

关键词： toluene aroylation unactivated tertiary benzamides directed ortho-lithiation nucleophilic acyl substitution reaction

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基于环境的三维激光实时去动态物体方法

计算机工程与设计 2024年第9期45卷 2627-2633页

作者：张志强张雷邹风山杜振军刘明敏中国科学院沈阳自动化研究所机器人学国家重点实验室辽宁沈阳110016 中国科学院机器人与智能制造创新研究院辽宁沈阳110169 中国科学院大学北京100049 沈阳新松机器人自动化股份有限公司辽宁沈阳110168

为提高三维激光传入点云算法框架的点云质量,减少移动物体对点云地图精度的影响,提出一种能够在框架前端基于环境特征的实时去除动态物体的方法。将点云投影得到深度矩阵和高度矩阵(z值矩阵),并从z值矩阵中提取出环境特征;利用环境特征... 详细信息

为提高三维激光传入点云算法框架的点云质量,减少移动物体对点云地图精度的影响,提出一种能够在框架前端基于环境特征的实时去除动态物体的方法。将点云投影得到深度矩阵和高度矩阵(z值矩阵),并从z值矩阵中提取出环境特征;利用环境特征将前后帧点云快速对齐;利用对齐后的前后帧点云得到z值差分矩阵进行筛选,并标记动态点云;以动态点云为中心,利用深度矩阵进行聚类,并将聚类得到的未标记点云进行标记,传入后端时舍弃标记的点云。分别在Ours数据集上以及KITTI数据集上验证了该方法的效果。

关键词：实时环境特征高度矩阵深度矩阵对齐前后帧聚类差分矩阵

DNA Extraction from Formalin-fixed and Paraffin-embedded Tissues by Triton X-100 for Effective Amplification of EGFR Gene by Polymerase Chain Reaction

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Chemical Research in Chinese Universities 2012年第4期28卷 662-665页

作者： WANG Xiao-feng du zhen-wu WU Meil ZHANG Yu-cheng JIANG Yang ZHANG Gui-zhen Central Laboratory China-Japan Union Hospital of Jilin UniversityChangchun 130033P.R.China Dental Department China-Japan Union Hospital of Jilin UniversityChangchun 130033P.R.China Department of Rectum Colon Surgery China-Japan Union Hospital of Jilin UniversityChangchun 130033P.R.China

For first-line non-small-cell lung cancer（NSCLC） therapy,detecting mutation status of the epidermal growth factor receptor（EGFR） gene constitutes a prudent test to identify patients who are most likely to benefit from EGFR-tyrosine kinase inhibitor（TKI） ***,the material for detecting EGFR gene mutation status mainly comes from formalin-fixed and paraffin-embedded（FFPE） *** extraction from FFPE and the amplification of EGFR gene by polymerase chain reaction（PCR） are two key steps for detecting EGFR gene *** showed a simple method of DNA extraction from FFPE tissues for the effective amplification of EGFR *** DNA from the FFPE tissues of NSCLC patients with 1% Triton X-100（pH=10.0） was performed by heating at 95 °C for 30 ***,a commercial kit was used to extract DNA from the same FFPE tissues of NSCLC patients for *** extracted products were used as template for amplifying the exons 18,19,20 and 21 of EGFR by PCR for different amplified *** show that DNA fragment size extracted from FFPE tissues with 1% Triton X was about 250―500 base pairs（bp）.However,DNA fragment size extracted from FFPE tissues via commercial kit was about from several hundreds to several thousands *** DNA yield extracted from FFPE tissues with 1% Triton X was larger than that via commercial *** about 500 bp fragment,four exons of EGFR could not be amplified more efficiently from extracted DNA with 1% Triton X than with commercial ***,for about 200 bp *** simple and non-laborious protocol could successfully be used to extract DNA from FFPE tissue for the amplification of EGFR gene by PCR,further screening of EGFR gene mutation and facilitating the molecular analysis of a large number of FFPE tissues from NSCLC patients.

关键词： EGFR gene amplification DNA extraction Formalin-fixed and paraffin-embedded tissue Non-small-cell lung cancer

Improved Allele-specific Polymerase Chain Reaction for Single Nucleotide Polymorphism Genotyping

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Chemical Research in Chinese Universities 2010年第2期26卷 259-262页

作者： WU Mei du zhen-wu LIU Jia-nan SONG Yang WANG Ya-li ZHANG Gui-zhen Department of Central Research China-Japan Union Hospital of Jilin University Changchun 130033 P. R. China

An improved allele-specific PCR（AS-PCR） approach was applied to investigating -55C/T polymorphism in promoter region of the uncoupling protein 3（UCP3）gene. AS-PCR is a competitive PCR method which is based on positioning the 3＇ base of a PCR primer to match one single nucleotide polymorphism（SNP） allele and accurately extend only the correctly matched primer. But it is limited in use because of its poor specificity. In this study, we improved the specificity of AS-PCR by introducing additional mismatch at the penultimate base of 3＇ end of AS-PCR primer in combination with decreasing the level of dNTP in the reaction mixture. Sensitivity, specificity and reliability of this method were assessed for both simple plasmid model and complex human genomic SNP targets. The -55C/T（rs1800849） polymorphisrn of the UCP3 gene was analyzed via this AS-PCR and restriction fragment length polymorphism（RFLP）, the latter was used as a gold standard. The results suggest that the increase in AS-PCR discrimination with this method should facilitate the use of this simple, rapid, and inexpensive technique for SNP genotyping application.

关键词： AS-PCR Polymorphism UCP3 SNP genotyping

Covariance of Floral and Vegetative Traits in Four Species of Ranunculaceae:A Comparison between Specialized and Generalized Pollination Systems

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Journal of Integrative Plant Biology 2008年第9期50卷 1161-1170页

作者： Jin-Liu Meng Xian-Hui Zhou Zhi-Gang Zhao Guo-zhen du Key Laboratory of Arid and Grassland Ecology of Ministry of Education at Lanzhou University Lanzhou 730000 China College of Life Sciences Wuhan University Wuhan 430072 China

Theory predicts that tighter correlation between floral traits and weaker relationship between floral and vegetative traits more likely occur in specialized flowers than generalized flowers, favoring by precise fit with pollinators. However, traits and trait correlations frequently vary under different environments. Through detecting spatiotemporal variation in phenotypic traits （floral organ size and vegetative size） and trait correlations in four Ranunculaceae species, we examined four predictions. Overall, our results supported these predictions to a certain degree. The mean coefficient of variation （CV） of floral traits in two specialized species （Delphinium kamaonense and Aconitum gymnandrum） was marginally significantly lower than that of another two generalized species （Trollius ranunculoides and Anemone obtusiloba）. The two specialized species also showed marginally significantly smaller CV in floral traits than vegetative size across the two species. The absolute mean correlation between floral and vegetative traits, or that between floral traits in species with specialized flowers was not significantly lower, or higher than that in generalized plants, weakly supporting the predictions. Furthermore, we documented a large variation in trait correlations of four species among different seasons and populations. Study of covariance of floral and vegetative traits will benefit from the contrast of results obtained from generalized and specialized pollination systems.

关键词： coefficient of variation floral traits generalized flower Ranunculaceae specialized flower trait correlation vegetative traits.

A novel method for the spectrophotometric determination of cefradine by using sodium nitroprusside as chromogenic reagent

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Chinese Chemical Letters 2008年第12期19卷 1470-1474页

作者： Hua Zhang Ling Li Wu Quan Min Li Xin zhen du College of Chemistry and Environmental Science Henan Normal University Xinxiang 453007 China College of Chemistry and Chemical Engineering Northwest Normal University Lanzhou 730070 China Henan Radio and Television University Zhengzhou 453008 China

A novel method is developed for the determination of cefradine by using sodium nitroprusside as chromogenic reagent. The experiment indicates that a russety product is formed by the reaction of cefradine with sodium nitroprusside in basic solution, and the maximum absorption wavelength （λmax） of russety product is 505 rim. And the sensitization of tetradecyl benzyl dimethyl ammonium chloride for the reaction of cefradine with sodium nitroprusside is remarkable, The apparent molar absorption coefficient （5505） is 2.81 × 103 L/mol cm. The linear equation isA = 0.0657 ＋ 0.00804C （μg/mL） in the range of 1.50-55.0μg/mL of cefradine with a correlation coefficient r = 0.9992, and the detection limit is 1.38 p,g/mL. This method has been applied to determine cefradine in capsule and tablet samples.

关键词： Cefradine Sodium nitroprusside Chromogenic reagent Spectrophotometry

Effects of Light on the Growth and Clonal Reproduction of Ligularia virgaurea

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Journal of Integrative Plant Biology 2008年第8期50卷 1015-1023页

作者： Man-Tang Wang Zhi-Gang Zhao Guo-zhen du Yan-Long He Key Laboratory of Arid and Grassland Agroecology under the Ministry of Education Lanzhou University Lanzhou 730000 China

Ligularia virgaurea is a perennial herb that is widely distributed in the alpine meadow on the eastern Qinghai-Tibet plateau. We investigated the patterns of growth and reproduction of L. virgaurea under two contrasting levels of light conditions for two continuous growing seasons. Our results showed that the light effects on the maximum relative growth rate, the shoot weight ratio and the root weight ratio differed between the two growing seasons. L. virgaurea reproduced initially through rhizome in the second growing season, rather than sexual reproduction. The proportion of genets with clonal reproduction decreased under shaded conditions. A minimum genet size should be attained for clonal reproduction to begin under the shaded conditions. There was a positive linear relationship between clonal reproduction and genet size. Light level affected the allocation of total biomass to clonal structures, with less allocation under the full natural irradiance than under the shaded conditions. There seemed to be a trade-off between vegetative growth and clonal reproduction under the full natural irradiance, in terms of smaller relative growth rates of genets with clonal reproduction than those without clonal reproduction. L. virgaurea emphasized clonal reproduction under the full natural irradiance, while the plant emphasized vegetative growth under the shaded conditions.

关键词： biomass allocation clonal reproduction Ligularia virgaurea relative growth rate threshold size

Study on brittleness templates for shale gas reservoirs——A case study of Longmaxi shale in Sichuan Basin,southern China

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Petroleum Science 2021年第5期18卷 1370-1389页

作者： Qamar Yasin Ghulam Mohyuddin Sohail Ke-Yu Liu Qi-zhen du Cyril DBoateng The Key Laboratory of Deep Oil and Gas China University of Petroleum(East China)Qingdao266580China Qingdao National Laboratory for Marine Science and Technology Laboratory for Marine Mineral ResourcesQingdao266237China Department of Civil Geological and Environmental EngineeringUniversity of SaskatchewanSaskatoonS7N 5C5Canada Department of Geological Engineering University of Engineering and TechnologyLahorePakistan

Differentiating brittle zones from ductile zones in low permeability shale formations is imperative for efficient hydraulic fracturing *** brittleness index(BI) is used to describe the rock resistance to hydraulic fracture initiation and propagation and measures the ease at which complex fracture networks can be *** this study,we constructed brittleness templates through the correlation of fundamental rock properties and geomechanical *** then employed the templates to distinguish the brittle,ductile,and brittle-ductile transition zones in the Longmaxi shale gas reservoir,Sichuan Basin of southern *** approach works in two ***,we suggest a new expression for the mineralogical BI by their respective weights based on the analysis of correlation coefficients between mechanical testing and XRD ***,we correlate TOC,porosity,pore fluid,natural fractures,and improved BI model with multiple elastic properties to define the brittle,ductile,and transitional zones in the Longmaxi shale gas reservoir of *** with the traditional mineralogy-based BI definition,the improved BI model differentiates the brittle and ductile zones and provides a better sense of the most suitable fracturing *** results show that the brittleness templates,which combine fundamental rock properties,improved BI model,and geomechanical characterization led to identifying favorable zones for hydraulic fracturing and enhanced shale *** proposed brittleness templates’ effectiveness was verified using data from horizontal wells,offset wells,shale gas wells from different origins,laboratory core testing,and seismic inversion of BI across the studied wells.

关键词： Brittleness index Geomechanical properties Petrophysical parameters Longmaxi shale