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Fractionated and Confined Crystallization of Polybutene-1 in Immiscible Polypropylene/Polybutene-1 Blends

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Chinese Journal of Polymer Science 2018年第7期36卷 859-865页

作者： Yao Xu Chen-Guang Liu hua-rong nie Ai-hua He Shandong Provincial Key Laboratory of Olefin Catalysis and Polymerization Key Laboratory of Rubber-Plastics (Ministry of Education) School of Polymer Science and Engineering Qingdao University of Science and Technology

In this work, the crystallization of immiscible polypropylene （PP）/polybutene-1 （PB） blends, in particular the effect of crystal morphology of PP （HTC, high Tm component） on the subsequent crystallization behavior of PB （LTC, low Tm component） was studied. Herein, we firstly indicated that PP/PB blends were not completely compatible but characterized as the LCST-like phase diagram above the melting temperature of PP. Crystallization of PP at different crystallization temperatures brought about different PP crystal morphologies and PB was segregated and confined at different locations. Much larger-sized domain of PB component appeared in PP spherulites resulting from the effects of non-negligible phase separation and the slower PP crystallization rate as PP crystallized at high temperature. As temperature continued to fall below Tm of PB, the fractionated and confined crystallization of PB occurred in the framework of PP spherulites, reflected by the decreased crystallization temperature （To） of PB and the formation of form I＇ beside form II. Notably, if PP previously crystallized at high Tc, fractionated crystallization of PB became predominant and confined crystallization of PB became weak due to the much wider droplet-size distribution of PB domains.

关键词： Polypropylene Polybutene Confined crystallization Morphology

Differential Polymorphic Transformation Behavior of Polybutene-1 with Multiple Isotactic Sequences

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Chinese Journal of Polymer Science 2020年第2期38卷 164-173,I0007页

作者： Ya-Ping Ma Wei-Ping Zheng Chen-Guang Liu hua-Feng Shao hua-rong nie Ai-hua He Shandong Provincial Key Laboratory of Olefin Catalysis and Polymerization Key Laboratory of Rubber-Plastics (Ministry of Education) Qingdao University of Science and Technology

For the solid-solid transformation from form Ⅱ to form Ⅰ of isotactic polybutene-1(iPB),the temperature dependence of form Ⅰ nucleation and growth was deemed to control the transformation ***,the relationship between formⅠ formation and form Ⅱ disappearance in the transformation process is not *** this work,the spontaneous crystal transformation from form Ⅱ to Ⅰ of iPB with 81 mol%mmmm sequence concentration is studied firstly by tracking the two processes,the decay of form Ⅱ and the yielding of form Ⅰ in a wide range of temperature spanning from 0℃ to 50℃ and in a long transformation time ranging from 5 min to 65 days with in situ FTIR and *** the literature reports,the decay rate of form Ⅱ is firstly found to be lower than the yielding rate of form Ⅰ at all studied temperatures,especially at low transition *** is attributed to the amorphous chains which locate near crystal lamella participating into the nucleation of form Ⅱ.The regular chain folding and growth of i PB form Ⅰ from amorphous chains containing short isotactic sequences also lead to an increase in crystallinity of form Ⅰ compared with that of initial form Ⅱ crystallized at 60℃.An increase in the annealing temperature results in decrease in crystallinity and increase in lamellae thickness of i PB formⅠ.

关键词： Polybutene-1 Polymorphic transformation Isotactic sequence Crystallinity Lamellae thickness

Advancements in S-scheme heterojunction materials for photocatalytic environmental remediation

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Journal of Materials Science & Technology 2024年第2期169卷 182-198页

作者： Changliang nie Xiaohan Wang Ping Lu Yukun Zhu Xin Li hua Tang School of Environmental Science and Engineering State Key Laboratory of Bio-fibers and Eco-textilesQingdao UniversityQingdao266071China Institute of Biomass Engineering Key Laboratory of Energy Plants Resource and UtilizationMinistry of Agriculture and Rural AffairsSouth China Agricultural UniversityGuangzhou510642China School of Environmental Science and Engineering Shandong UniversityQingdao266237China

Recently,S-scheme heterojunctions have gained considerable attention in the field of photocatalytic environmental remediation as their potential to achieve efficient spatial charge separation coupled with strong redox ***,this review provides an overview of the current state-of-the-art in the development of S-scheme-based photocatalysts for the purification of environmental *** review first covers the fundamentals of heterogeneous photocatalysis for environmental ***,an introduction to the background,mechanism,design principles,and characterization techniques of S-scheme heterojunctions is ***,the review presents a comparison and summary of using various S-scheme photocatalysts for the removal of several target pollutants,such as bacteria,heavy metals,nitrogen oxides,antibiotics,and ***,the modification strategies of S-scheme heterojunction photocatalysts are also ***,a brief discussion of the challenges and prospects associated with S-scheme photocatalytic systems is demonstrated.

关键词： S-scheme heterojunctions Photocatalyst Pollutant Environmental remediation

Identification and Characteristics Analysis of Micro-Seismic Signals in the Haima Seep Area

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Journal of Earth Science 2024年第1期35卷 288-291页

作者： Xiangchun Wang Bing nie Zhiyu Wu Weiwei Wang hua Chen China University of Geosciences Beijing 100083China CNOOC China Limited Shenzhen BranchShenzhen 518000China Guangzhou Marine Geological Survey Guangzhou 511458China CNOOC China Limited Shanghai BranchShanghai 200335China

*** recent years,with the steady development of offshore energy exploration technology,submarine gas seepage sites,and their products are gradually being identified and *** submarine cold seep is a seepage phenomenon in which hydrocarbon gases stored deep in the seafloor are transported to seawater by gushing or seepage under the action of tectonic compression(Roy et al.,2019;Tinivella and Giustiniani,2016).

关键词： submarine Seismic offshore

lncRNA ZNF593-AS inhibits cardiac hypertrophy and myocardial remodeling by upregulating Mfn2 expression

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Frontiers of Medicine 2024年第3期18卷 484-498页

作者： Xiang nie Jiahui Fan Yanwen Wang rong Xie Chen Chen huaping Li Dao Wen Wang Division of Cardiology Department of Internal MedicineTongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan430030China Hubei Key Laboratory of Genetics and Molecular Mechanisms of Cardiological Disorders Wuhan430030China

lncRNA ZNF593 antisense(ZNF593-AS)transcripts have been implicated in heart failure through the regulation of myocardial *** decreased transcriptional activity of ZNF593-AS has also been detected in cardiac ***,the function of ZNF593-AS in cardiac hypertrophy remains ***,we report that the expression of ZNF593-AS reduced in a mouse model of left ventricular hypertrophy and cardiomyocytes in response to treatment with the hypertrophic agonist phenylephrine(PE).In vivo,ZNF593-AS aggravated pressure overload–induced cardiac hypertrophy in knockout *** contrast,cardiomyocyte-specific transgenic mice(ZNF593-AS MHC-Tg)exhibited attenuated TAC-induced cardiac *** vitro,vector-based overexpression using murine or human ZNF593-AS alleviated PE-induced myocyte hypertrophy,whereas GapmeR-induced inhibition aggravated hypertrophic *** using RNA-seq and gene set enrichment analyses,we identified a link between ZNF593-AS and oxidative phosphorylation and found that mitofusin 2(Mfn2)is a direct target of ***593-AS exerts an antihypertrophic effect by upregulating Mfn2 expression and improving mitochondrial ***,it represents a promising therapeutic target for combating pathological cardiac remodeling.

关键词： lncRNA ZNF593-AS cardiac hypertrophy Mfn2 oxidative phosphorylation

Simulation and evaluation study of atmospheric aerosol nonsphericity as a function of particle size

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Particuology 2024年第7期90卷 281-291页

作者： Qianjun Mao Xin nie School of Urban Construction Wuhan University of Science and TechnologyWuhan430065China College of New Energy and Materials Northeast Petroleum UniversityDaqing163318China

Aerosol nonsphericity causes great uncertainty in radiative forcing assessments and climate *** considerable studies have attempted to quantify this uncertainty,the relationship between aerosol nonsphericity and particle size is usually not considered,thus reducing the accuracy of the *** this study,a coupled inversion algorithm combining an improved stochastic particle swarm optimization algorithm and angular light scattering is used for the nonparametric estimation of aerosol nonsphericity variation with particle size,and the optimal sample selection method is employed to screen the *** on the verification of inversion accuracy,the variation of aerosol aspect ratio with particle size based on the ellipsoidal model in global regions has been obtained from Aerosol Robotic Network(AERONET)data,and the effect of nonsphericity on radiative forcing and dry deposition has been *** results show that the aspect ratio increases with particle size in all regions,with the maximum ranging from 1.4 to 1.8 in the desert,reflecting the differences in aerosol composition at different particle *** radiation calculations,considering aerosol nonsphericity makes the aerosol cooling effect weaker and surface radiative fluxes increase,but hardly changes the aerosol absorption,with maximum differences of 9.22%and 22.12%at the bottom and top of the atmosphere,***,the differences in radiative forcing between aspect ratios as a function of particle size and not varying with particle size are not significant,averaging less than 2%.Besides,the aspect ratio not varying with particle size underestimates the deposition velocity of small particles and overestimates that of large particles compared to that as a function of particle size,with maximum differences of 7%and 4%,respectively.

关键词： Aerosol nonsphericity Inversion Aspect ratio Radiative forcing Dry deposition velocity

Effects of aspirin on colon cancer usingquantitative proteomic analysis

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Cancer Pathogenesis and Therapy 2024年第2期2卷 121-131页

作者： Yan Zhang Haitao Sun Yu Ji Fang nie rong Wang Wei Han Central Laboratory Beijing Luhe HospitalCapital Medical UniversityBejing 101149China Department of General Surgery Beijing Luhe HospitalCapital Medical UniversityBejing 101149China Central Laboratory Xuanwu HospitalCapital Medical UniversityBeijing 100053China

Background:Colon cancer is one of the most prevalent digestive cancers *** of epidemiological,experimental,and clinical studies suggest that aspirin inhibits the development of colon *** study aimed to systematically elucidate the molecular mechanisms by which aspirin prevents colon ***:We determined the global protein expression profiles of colorectal cancer and aspirin-treated cells using quantitative proteomic *** analyzed the proteomic results using bioinformatics(including differential pro-teins,protein annotation,Kyoto Encyclopedia of Genes and Genomes[KEGG]pathways,and protein-protein inter-action[PPI]network).The viability of the colon cancer cell line and HT29 cells treated with aspirin was determined using the cell counting kit-8 *** differentially expressed proteins,such as p53 and cyclin-dependent kinase 1(CDK1),were quantified using real-time polymerase chain reaction(PCR)and Western *** measured cell cycle distribution and apoptosis in HT29 cells exposed to aspirin using fluorescence-activated cell sorting(FACS).Results:We found that 552 proteins were significantly dysregulated,of which 208 and 334 were upregulated and downregulated,respectively,in colon cancer cells exposed to 10 mmol/L of aspirin(95%confidence interval[CI]:-1.269 to-0.106,P<0.05).Further gene enrichment analysis revealed that cell cycle-related proteins,such as p53 and CDK1,were significantly differentially *** analysis showed that after 24 h of aspirin exposure,the level of p53 increased by 2.52-fold and CDK1 was downregulated to half that of the controls in HT29 cells(95%CI:-0.619 to-0.364,P<0.05).Real-time PCR and Western blotting results showed that p53 was upregulated(95%CI:-3.088 to-1.912,P<0.001)and CDK1 was significantly downregulated after aspirin exposure in colon cancer cells(95%CI:0.576 to 1.045,P<0.05).We observed that aspirin promoted G1/S cell cycle arrest in HT29 *** confirmed that asp

关键词： Colon cancer Proteomics Aspirin Cell cycle Cell apoptosis

Convergence analysis for complementary-label learning with kernel ridge regression

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Applied Mathematics:A Journal of Chinese Universities 2024年第3期 533-544页

作者： nie Wei-lin WANG Cheng XIE Zhong-hua School of Mathematics and Statistics Huizhou University School of Computer Science and Engineering Huizhou University

Complementary-label learning (CLL) aims at finding a classifier via samples with complementary labels. Such data is considered to contain less information than ordinary-label samples. The transition matrix between the true label and the complementary label, and some loss functions have been developed to handle this problem. In this paper, we show that CLL can be transformed into ordinary classification under some mild conditions, which indicates that the complementary labels can supply enough information in most cases. As an example,an extensive misclassification error analysis was performed for the Kernel Ridge Regression(KRR) method applied to multiple complementary-label learning (MCLL), which demonstrates its superior performance compared to existing approaches.

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3D printedβ-sheet-reinforced natural polymer hydrogel bilayer tissue engineering scaffold

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Science China(Technological Sciences) 2024年第4期67卷 1170-1184页

作者： ZHAO XinRui nie XiongFeng ZHANG XiaoPing SUN YaGe YANG rong BIAN XinYu ZHANG Qian WANG HongYing XU ZiYang LIU WenGuang School of Materials Science and Engineering Tianjin Key Laboratory of Composite and Functional MaterialsTianjin UniversityTianjin 300350China

It remains a significant challenge to fabricate natural polymer(NP)hydrogels with anti-swelling ability and high strengths in the physiological ***,theβ-sheet-reinforced NP hydrogel is developed by copolymerizing methacrylated gelatin(GelMA)and methacrylated silk fibroin(SFMA)in aqueous solution,followed by ethanol treatment(named GelMA-SFMAAL).Theβ-sheets formed by SFMA can act as a stable physical crosslink to enhance the mechanical properties and prolong the degradation of the GelMA ***,the chemical crosslinking in the GelMA-SFMA hydrogel prevents excessive aggregation of hydrophobicβ-sheets,thereby avoiding the formation of brittle *** obtained GelMA-SFMA-AL hydrogels exhibit considerably enhanced mechanical properties(Young's modulus:0.89–3.68 MPa;tensile strength:0.31–0.96 MPa;toughness:0.09–0.63 MJ/m^(3);compressive modulus:0.78–2.20 MPa;compressive strength:2.65–5.93 MPa)compared with GelMA-SFMA hydrogels(Young's modulus:0.04–0.13 MPa;tensile strength:0.04–0.07 MPa;toughness:0.01–0.02 MJ/m^(3);compressive modulus:0.03–0.09 MPa;compressive strength:0.30–0.64 MPa).A bilayer osteochondral scaffold is constructed via digital light processing(DLP)three-dimensiaonl(3D)printing technology,comprising GelMA-SFMA@diclofenac sodium(DS)-AL as the top layer and GelMA-SFMA@bioactive glass(BG)-AL as the bottom *** bilayer hydrogel scaffold is demonstrated to support cell attachment and spreading,and facilitate osteogenic differentiation of rat bone marrow stem cells in *** vivo implantation experiment suggests this bilayer scaffold is promising to be used for osteochondral tissue regeneration.

关键词： silk fibroin β-sheet high-strength hydrogel natural polymer osteochondral regeneration