检索结果-南通市图书馆

Critical Role of Ethylene-Propylene Block Copolymer in Impact Polypropylene Copolymer

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Polymer Science 2024年第3期42卷 344-351,I0007页

作者： Yu-Hui Tang na Zhang Wei Bao Wei Jiang Yuan Lin Zhao-Hui su State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China School of Applied Chemistry and Engineering University of Science and Technology of ChinaHefei 230026China

Ethylene-propylene block copolymer(EbP) is a vital component in impact polypropylene copolymer(IPC), yet its distribution in the multiphase composite material and how it influences the phase structure and the mechanical properties are not well understood. In this work,four IPCs were investigated by atomic force microscopy-infrared(AFM-IR) to assess the phase compositions in situ, based on which in conjunction with the chain microstructure information obtained ex situ the distributions of the copolymer components were derived for each alloy. For the IPCs whose EbP comprises long P and long E segments, the EbP fraction was found to phase separate from the rubber and the PP matrix to form the cores of the disperse particles with the E-P segmented copolymer(EsP). In contrast, in the IPC with EbP composed of long P and short E segments, the EbP fraction formed an outer shell for the rubber particles with the cores comprising the EsP alone, and this IPC, containing a lower E comonomer content than its counterpart, exhibited both better impact resistance and higher flexural modulus. These results clarify how the chain structure of EbP governs the phase morphology in IPC, which in turn impacts the properties of the composite material.

关键词： Impact polypropylene copolymers AFM-IR Ethylene-propylene block copolymers Core-shell rubber particles

Temporal assembly patterns of microbial communities in three parallel bioreactors treating low-concentration coking wastewater with differing carbon source concentrations

在线全文

学校读者我要写书评

暂无评论

Journal of Environmental Sciences 2024年第3期137卷 455-468页

作者： Weijia Li Yu Xia na Li Jie chang Jing Liu Pei Wang Xuwen He School of Chemical and Environmental Engineering China University of Mining and Technology-BeijingBeijing 100083China

Carbon source is an important factor of biological treatment systems, the effects of which on their temporal community assembly patterns are not sufficiently understood currently.In this study, the temporal dynamics and driving mechanisms of the communities in three parallel bioreactors for low-concentration coking wastewater(CWW) treatment with differing carbon source concentrations(S0 with no glucose addition, S1 with 200 mg/L glucose addition and S2 with 400 mg/L glucose addition) were comprehensively studied. Highthroughput sequencing and bioinformatics analyses including network analysis and Infer Community Assembly Mechanisms by Phylogenetic bin-based null model(iCAMP) were used. The communities of three systems showed turnover rates of 0.0029~0.0034 every 15days. Network analysis results showed that the S0 network showed higher positive correlation proportion(71.43%) and clustering coefficient(0.33), suggesting that carbon source shortage in S0 promoted interactions and cooperation of microbes. The neutral community model analysis showed that the immigration rate increased from 0.5247 in S0 to 0.6478in S2. The iCAMP analysis results showed that drift(45.89%) and homogeneous selection(31.68%) dominated in driving the assembly of all the investigated microbial communities.The contribution of homogeneous selection increased with the increase of carbon source concentrations, from 27.92% in S0 to 36.08% in S2. The OTUs participating in aerobic respiration and tricarboxylic acid(TCA) cycle were abundant among the bins mainly affected by deterministic processes, while those related to the metabolism of refractory organic pollutants in CWW such as alkanes, benzenes and phenols were abundant in the bins dominated by stochastic processes.

关键词： Coking wastewater treatment Temporal dynamics Network analysis Deterministic processes Stochastic processes

Gut microbiota induced abnormal amino acids and their correlation with diabetic retinopathy

在线全文

学校读者我要写书评

暂无评论

International Journal of Ophthalmology(English edition) 2024年第5期17卷 883-895页

作者： Sheng-Qun Jiang su-na Ye Yin-Hua Huang Yi-Wen Ou Ke-Yang Chen Jian-su Chen Shi-Bo Tang Aier Eye Hospital Jinan UniversityGuangzhou 510000Guangdong ProvinceChina Aier Eye Institute and changsha Aier Hospital Changsha 410000Hunan ProvinceChina The First Affiliated Hospital of Bengbu Medical University Bengbu 233000Anhui ProvinceChina School of Public Health Anhui Medical UniversityHefei 230000Anhui ProvinceChina

AIM:To explore the correlation of gut microbiota and the metabolites with the progression of diabetic retinopathy(DR)and provide a novel strategy to elucidate the pathological mechanism of DR.METHODS:The fecal samples from 32 type 2 diabetes patients with proliferative retinopathy(PDR),23 with nonproliferative retinopathy(NPDR),27 without retinopathy(DM),and 29 from the sex-,age-and BMI-matched healthy controls(29 HC)were analyzed by 16S rDna gene sequencing.Sixty fecal samples from PDR,DM,and HC groups were assayed by untargeted metabolomics.Fecal metabolites were measured using liquid chromatographymass spectrometry(LC-MS)analysis.Associations between gut microbiota and fecal metabolites were analyzed.REsuLTS:A cluster of 2 microbiome and 12 metabolites accompanied with the severity of DR,and the close correlation of the disease progression with PDR-related microbiome and metabolites were found.To be specific,the structure of gut microbiota differed in four groups.Diversity and richness of gut microbiota were significantly lower in PDR and NPDR groups,than those in DM and HC groups.A cluster of microbiome enriched in PDR group,including Pseudomonas,Ruminococcaceae-UCG-002,Ruminococcaceae-UCG-005,Christensenellaceae-R-7,was observed.Functional analysis showed that the glucose and nicotinate degradations were significantly higher in PDR group than those in HC group.Arginine,serine,ornithine,and arachidonic acid were significantly enriched in PDR group,while proline was enriched in HC group.Functional analysis illustrated that arginine biosynthesis,lysine degradation,histidine catabolism,central carbon catabolism in cancer,D-arginine and D-ornithine catabolism were elevated in PDR group.Correlation analysis revealed that Ruminococcaceae-UCG-002 and Christensenellaceae-R-7 were positively associated with L-arginine,ornithine levels in fecal samples.CONCLUSION:This study elaborates the different microbiota structure in the gut from four groups.The relative abundance of Ruminococcaceae-UCG-002 and Parabacteroides are

关键词： proliferative retinopathy gut microbiota Ruminococcaceae amino acid metabolism arginine

A continuous and long-term in-situ stress measuring method based on fiber optic. Part I: Theory of inverse differential strain analysis

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Petroleum Science 2024年第2期21卷 1171-1189页

作者： Kun-Peng Zhang Mian Chen chang-Jun Zhao su Wang Yong-Dong Fan State Key Laboratory of Petroleum Resources and Prospecting China University of PetroleumBeijing102249China MOE Key Laboratory of Petroleum Engineering in China University of Petroleum Beijing102249China Beijing International Center for Gas Hydrate School of Earth and Space SciencesPeking UniversityBeijing100871China

A method for in-situ stress measurement via fiber optics was proposed. The method utilizes the relationship between rock mass elastic parameters and in-situ stress. The approach offers the advantage of long-term stress measurements with high spatial resolution and frequency, significantly enhancing the ability to measure in-situ stress. The sensing casing, spirally wrapped with fiber optic, is cemented into the formation to establish a formation sensing nerve. Injecting fluid into the casing generates strain disturbance, establishing the relationship between rock mass properties and treatment pressure.Moreover, an optimization algorithm is established to invert the elastic parameters of formation via fiber optic strains. In the first part of this paper series, we established the theoretical basis for the inverse differential strain analysis method for in-situ stress measurement, which was subsequently verified using an analytical model. This paper is the fundamental basis for the inverse differential strain analysis method.

关键词： In-situ stress Fiber optic Orthotropic elastic Differential evolution ABAQUS

Morphological and sulfur-Isotopic Characteristics of Pyrites in the Deep Sediments from Xisha Trough,South China Sea

在线全文

学校读者我要写书评

暂无评论

Journal of Ocean University of China 2024年第1期23卷 138-148页

作者： chang Jingyi LIU Yujia LU Hailong LU Jing’an su Xin YE Jianliang XIE Wenwei College of Engineering Peking UniversityBeijing 100871China Beijing International Center for Gas Hydrate School of Earth and Planetary SciencesPeking UniversityBeijing 100871China School of Marine Science Nanjing University of Information Science and TechnologyNanjing 210044China MLR Key Laboratory of Marine Mineral Resources Guangzhou Marine Geological SurveyMinistry of Land and ResourcesGuangzhou 510075China School of Ocean Sciences China University of GeosciencesBeijing 100083China

Pyrite is one of the common authigenic minerals in marine sediments.Previous studies have shown that the morphological and isotopic characteristics of pyrite are closely related to the geochemical environment where it is formed.To better understand the for-mation mechanism of authigenic pyrite,we analyzed the isotopic composition,morphology,and distribution of pyrite in the sediment at 500m below the seafloor from Xisha Trough,South China Sea.Mineral morphologies were observed by scanning electron micros-copy and Raman spectrography.X-Ray computed tomography was applied to measure the particle size of pyrite.The size of pyrite crystals in the matrix sediment mainly ranged between 25 and 65µm(av.ca.40µm),although crystals were larger(av.ca.50μm)in the veins.The pyrites had a fine-grained truncated octahedral shape with occasionally well-developed growth steps,which implies the low growth rate and weak anaerobic oxidation of methane-sulfate reduction when pyrite was formed.Theδ^(34)S values of pyrites ranged from+20.8‰Vienna-defined Canyon Diablo Troilite(V-CDT)to+33.2‰V-CDT and from+44.8‰V-CDT to+48.9‰,which suggest two growth stages.In the first stage,with the continuous low methane flux,the pyrite possibly formed in an environment with good access to seawater.In the second stage,the pyrites mainly developed in sediment fractures and appeared in veins,probably due to the limited availability of sulfate.The less exposure of pyrite to the environment in the second stage was probably caused by sediment accumulation or perturbation.In this study,an episodic pyritization process was identified,and the paleoenvironment was reconstructed for the sediment investigated.

关键词： pyrite sulfur isotope AOM methane flux Xisha Trough South China Sea

Visual test paper based on Au/δ-MnO_(2) hollow nanosphere oxidase-like activity regulation using hexavalent chromium as a smart switch

在线全文

学校读者我要写书评

暂无评论

Rare Metals 2024年第2期43卷 711-722页

作者： Wen-chang Zhuang Hai-Yue Zhang Zhen-Yang Chen Wen-Jing Cheng Wei-Dan na Zhao Li Lin Tian School of Materials and Chemical Engineering Xuzhou University of TechnologyXuzhou221018China School of Chemistry and Environmental Science Yili Normal UniversityYining835000China

Paper-based sensing platform is a point of need analytical toolkit for safety testing.However,the sensitivity,specificity,and simplicity are still challenging.Herein,we report a novel strategy(Au/δ-MnO_(2) hollow nanosphere and 3,3′,5,5′-tetramethylbenzidine(TMB)induced test strips for signal-on detection)that can be utilized for hexavalent chromium(Cr^(6+))detection.Interestingly,Cr^(6+)(CrO_(4)^(2−)) as a smart switch can remarkably enhance the oxidase-like activity of Au/δ-MnO_(2) hollow nanosphere.The presence of Cr^(6+) can regulate the surface electronic redistribution of Au/δ-MnO_(2) and adjust the geometric configuration,which leads to the improvement in oxidase-like activity of Au/δ-MnO_(2).As a proof-of-concept application,a visual paper-based sensing platform of Cr^(6+) along with quantitative analysis by the test strips was successfully constructed.This paper-based sensing platform exhibits a linear range with excellent selectivity for other interfering substances and lower limit of detection of 0.09μmol·L^(−1),providing a promising toolkit at-home Cr^(6+) measurement and environmental monitoring.

关键词： Point of need Colorimetric biosensing platform Au/δ-MnO_(2) hollow nanosphere Test strip Cr^(6+)

IQGAP3 promotes the progression of glioma as an immune and prognostic marker

在线全文

学校读者我要写书评

暂无评论

Oncology Research 2024年第4期32卷 659-678页

作者： XIAOFENG GAO JUANJUAN GE XUZHENG GAO na MEI YANTING su SHIGANG SHAN WENBIN QIAN JIANGHENG GUAN ZHENWANG ZHANG LONG WANG Hubei Provincial Key Laboratory of Diabetic Cardiovascular Diseases Xianning Medical CollegeHubei University of Science and TechnologyXianning437100China School of Stomatology and Ophthalmology Xianning Medical CollegeHubei University of Science and TechnologyXianning437100China School of Basic Medical Sciences Xianning Medical CollegeHubei University of Science and TechnologyHubei University of Science and TechnologyXianning437100China School of Pharmacy Xianning Medical CollegeHubei University of Science and TechnologyXianning437100China Department of Neurosurgery The General Hospital of Chinese PLA Central Theater CommandWuhan430070China

Background:IQGAP3 plays a crucial role in regulating cell proliferation,division,and cytoskeletal organization.Abnormal expression of IQGAP3 has been linked to various tumors,but its function in glioma is not well understood.Methods:Various methods,including genetic differential analysis,single-cell analysis,ROC curve analysis,Cox regression,Kaplan-Meier analysis,and enrichment analysis,were employed to analyze the expression patterns,diagnostic potential,prognostic implications,and biological processes involving IQGAP3 in normal and tumor tissues.The impact of IQGAP3 on immune infiltration and the immune microenvironment in gliomas was evaluated using immunofluorescence.Additionally,the cBioPortal database was used to analyze copy number variations and mutation sites of IQGAP3.Experimental validation was also performed to assess the effects of IQGAP3 on glioma cells and explore underlying mechanisms.Results:High IQGAP3 expression in gliomas is associated with an unfavorable prognosis,particularly in wild-type IDH and 1p/19q non-codeleted gliomas.Enrichment analysis revealed that IQGAP3 is involved in regulating the cell cycle,PI3K/AKT signaling,p53 signaling,and PLK1-related pathways.Furthermore,IQGAP3 expression may be closely related to the immunosuppressive microenvironment of glioblastoma.BRD-K88742110 and LY-303511 are potential drugs for targeting IQGAP3 in anti-glioma therapy.In vitro experiments showed that downregulation of IQGAP3 inhibits the proliferation and migration of glioma cells,with the PLK1/PI3K/AKT pathway potentially playing a crucial role in IQGAP3-mediated glioma progression.Conclusion:IQGAP3 shows promise as a valuable biomarker for diagnosis,prognosis,and immunotherapeutic strategies in gliomas.

关键词： IQGAP3 Tumor immune infiltration Prognosis Glioma Biomarker

Aerodynamic Features of High-Speed Maglev Trains with Different Marshaling Lengths Running on a Viaduct under Crosswinds

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Computer Modeling in Engineering & Sciences 2024年第7期140卷 975-996页

作者： Zun-Di Huang Zhen-Bin Zhou Ning chang Zheng-Wei Chen su-Mei Wang School of Rail Transportation Wuyi UniversityJiangmen529020China national Rail Transit Electrification and Automation Engineering Technology Research Center(Hong Kong Branch) The Hong Kong Polytechnic UniversityHong Kong999077China Department of Civil and Environmental Engineering The Hong Kong Polytechnic UniversityHong Kong999077China

The safety and stability of high-speed maglev trains traveling on viaducts in crosswinds critically depend on their aerodynamic characteristics.Therefore,this paper uses an improved delayed detached eddy simulation(IDDES)method to investigate the aerodynamic features of high-speed maglev trains with different marshaling lengths under crosswinds.The effects of marshaling lengths(varying from 3-car to 8-car groups)on the train’s aerodynamic performance,surface pressure,and the flow field surrounding the train were investigated using the three-dimensional unsteady compressible navier-Stokes(N-S)equations.The results showed that the marshaling lengths had minimal influence on the aerodynamic performance of the head and middle cars.Conversely,the marshaling lengths are negatively correlated with the time-average side force coefficient(CS)and time-average lift force coefficient(Cl)of the tail car.Compared to the tail car of the 3-car groups,the CS and Cl fell by 27.77%and 18.29%,respectively,for the tail car of the 8-car groups.It is essential to pay more attention to the operational safety of the head car,as it exhibits the highest time average CS.Additionally,the mean pressure difference between the two sides of the tail car body increased with the marshaling lengths,and the side force direction on the tail car was opposite to that of the head and middle cars.Furthermore,the turbulent kinetic energy of the wake structure on the windward side quickly decreased as marshaling lengths increased.

关键词： High-speed maglev train marshaling lengths crosswinds aerodynamic features

Synthesis of Long-Chain Oligomeric Donor and Acceptors via Direct Arylation for Organic Solar Cells

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Journal of Chemistry 2024年第5期42卷 523-532页

作者： Yu Wu Xin-Yu He Xu-Min Huang Ling-Jun Yang Peng Liu na Chen chang-Zhi Li Shi-Yong Liu Jiangxi Provincial Key Laboratory of Functional Molecular Materials Chemistry College of MaterialsMetallurgical and ChemistryJiangxi University of Science and TechnologyGanzhouJiangxi341000 China Department of Polymer Science and Engineering Zhejiang UniversityHangzhouZhejiang310027 China

The rapid synthesis of structurally complicated electron donors&acceptors still remains a major challenge in organic solar cells(OSC).In this work,we developed a highly efficient strategy to access long-chain oligomeric donor and acceptors for OSC applications.A series of cyclopentadithiophene(CPDT)and benzothiadiazole(BT)-basedπ-conjugated oligomers,i.e.,three oligomeric acceptors(BTDT)n-IC(n=1—3)and one long-chain oligomeric donor(BTDT)4-RD,are facilely synthesized by an atom-and step-economical,and labor-saving direct C—H arylation(DACH)reaction(i.e.,C—H/C—Br cross coupling).Note that(BTDT)4-RD involving five CPDT,four BT and two rhodamine(RD)building blocks is the longest oligomeric donor in the fullerene-free OSC devices ever reported.The dependence of the structure-property-performance correlation of(BTDT)n-IC(n=1—3)and(BTDT)4-RD on theπ-conjugation lengths is thoroughly investigated by opto-electrochemical measurements,bulk heterojunction(BHJ)OSC devices and microscopies.The(BTDT)1-IC:PBDB-T and(BTDT)4-RD:Y6 BHJs achieve power conversion efficiencies of 9.14%and 4.51%,respectively.Our findings demonstrate that DACH reaction is a powerful tool to tune the opto-electronic properties and device performances by regulating the lengths ofπ-conjugated oligomers with varied numbers of repeating units.

关键词： Long-chainπ-conjugated oligomer Organic solar cells Direct arylation Atom-economical synthesis Cyclopentadithiophene Benzothiadiazole C—H activation Conjugation Oligomers