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Solid-state impedance spectroscopy studies of dielectric properties and relaxation processes in Na_(2)O–V_(2)O_(5)–Nb_(2)O_(5)–P_(2)O_(5) glass

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international Journal of Minerals,Metallurgy and Materials 2024年第1期31卷 186-196页

作者： Sara Marijan Luka Pavic division of Materials chemistry Ruđer Boskovic InstituteBijenicka 54HR-10000 ZagrebCroatia

Solid-state impedance spectroscopy(SS-iS)was used to investigate the influence of structural modifications resulting from the addition of Nb2O5 on the dielectric properties and relaxation processes in the quaternary mixed glass former(MGF)system 35Na_(2)O–10V_(2)O_(5)–(55-x)P_(2)O_(5)–xNb_(2)O_(5)(x=0–40,mol%).The dielectric parameters,including the dielectric strength and dielectric loss,are determined from the frequency and temperature-dependent complex permittivity data,revealing a significant dependence on the Nb2O5 *** transition from a predominantly phosphate glass network(xion i)to a mixed niobate–phosphate glass net-work(10≤x≤20,region ii)leads to an increase in the dielectric parameters,which correlates with the observed trend in the direct-cur-rent(DC)*** the predominantly niobate network(x≥25,region iii),the highly polarizable nature of Nb5+ions leads to a fur-ther increase in the dielectric permittivity and dielectric *** is particularly evident in Nb-40 glass-ceramic,which contains Na_(13)Nb_(35)O_(94) crystalline phase with a tungsten bronze structure and exhibits the highest dielectric permittivity of 61.81 and the lowest loss factor of 0.032 at 303 K and 10 *** relaxation studies,analyzed through modulus formalism and complex impedance data,show that DC conductivity and relaxation processes are governed by the same mechanism,attributed to ionic *** contrast to glasses with a single peak in frequency dependence of imaginary part of electrical modulus,M″(ω),Nb-40 glass-ceramic exhibits two distinct contributions with similar relaxation *** high-frequency peak indicates bulk ionic conductivity,while the additional low-fre-quency peak is associated with the grain boundary effect,confirmed by the electrical equivalent circuit(EEC)*** scaling characteristics of permittivity and conductivity spectra,along with the electrical modulus,validate time-temperature superposition and demonstrate a

关键词： phosphate glasses glass-ceramics impedance spectroscopy dielectric properties relaxation processes permittivity scaling conductivity scaling modulus formalism

New approach for particle size and shape analysis of iron-based oxygen carriers at multiple oxidation states

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Particuology 2024年第7期90卷 493-503页

作者： Victor Purnomo Marcelo Dal Belo Takehara Robin Faust Lidiya Abdisa Ejjeta Henrik Leion division of Energy and Materials Department of Chemistry and Chemical EngineeringChalmers University of TechnologyGöteborg 41258Sweden division of Energy Science Department of Engineering Sciences and MathematicsLuleåUniversity of TechnologyLuleå97187Sweden

One of the crucial issues in the chemical looping technology lies in its bed material:the oxygen *** size analysis of an oxygen carrier is important since in a fluidized bed the material can only work well within a specific size *** the favorable size ranges for oxygen carrier materials have already been reported,none of the published studies has analyzed the particle size and shape of oxygen carriers in ***,the effect of oxygen carriers'oxidation degree on such properties has not been considered *** study aimed to report the particle size and shape analysis of five iron-based oxygen carriers,one natural ore,one synthetic material,and three residue products,at different oxidation degrees using dynamic image analysis(DiA).The oxygen carriers were prepared at different mass conversion degrees in a fluidized bed batch *** size distribution,sphericity,and aspect ratio of the oxygen carrier particles were examined experimentally using a Camsizer *** results show that the DiA method was successfully able to analyze the particle size and shape of our oxygen carriers with satisfying accuracy for *** oxidation state of the investigated materials seems to only affect the particle size and shape of oxygen carriers to a minor ***,exposures to redox cycles in a fluidized bed reactor may alter the particle size and shape of most oxygen carriers.

关键词： Oxygen carrier Size and shape analysis Dynamic image analysis Oxidation state Fluidized bed Chemical looping

Utilizing a metal-forging inspired chain combing strategy to enhance properties and expand applications of Nylon 66 plastic via heat inducing

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Nano Research 2024年第3期17卷 2164-2171页

作者： Junyu Yang Jiangwei Zhang Nan Wang Guangyuan Zhou division of Energy Materials Daglian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023China innovation Center of Energy Material and chemistry College of Chemistry and Chemical EngineeringInner Mongolia UniversityHohhot 010021China

The mechanical properties of engineering plastics can be enhanced through effective surface mechanical treatment(SMT),which can be applied to various types of engineering plastics,eliminating the limitations of conventional polymer processing and could potentially extend their applications and improve their performance and reliability as structural-functional *** by metal forging,this work proposes a simple and effective SMT strategy to enhance the mechanical properties of polyamide 66(PA66).Tensile tests have shown that SMTed PA66 samples exhibit significant improvements in both Young’s modulus and ultimate tensile strength(UTS),with a 2104 MPa Young’s modulus,almost double that of the pristine samples,and a 35.56%increase in UTS,reaching 183 ***,the modulus within the localized SMTed surface layer could reach up to 14 GPa,which is approximately 14 times higher than that of the pristine *** Vickers hardness within the localized SMTed surface layer can be doubled,reaching 10.72 Hv,and the crystallinity can increase by approximately 20%compared to the untreated ***,force field molecular dynamics(FFMD)simulations were conducted to investigate the ternary relationship between the SMT method,PA66’s molecular structure,and its *** combination of MD simulations and versatile structural characterizations provides evidence that the SMT method’s mechanism,under heat induction,results in a chain-combing procedure that changes the polymer’s molecular morphology microscopically and enhances its mechanical properties macroscopically.

关键词： Nylon 66 mechanical properties hardness crystallinity structural characterizations molecular dynamics simulation

Orientation Bias of Self-Assembled Alkanes and Their Derivatives Under Dynamic Lateral Nanoconfinement Conditions

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CCS chemistry 2024年第4期6卷 1024-1033页

作者： Conditions Lihua Yu Yuanzhi Xia Tianze Hu Brent Daelemans Steven De Feyter Department of chemistry Division of Molecular Imaging and PhotonicsKU LeuvenB-3001 Leuven

Self-assembled molecular networks(SAMNs)formed on crystalline solid substrates result from the spontaneous arrangement of individual molecules into structured *** interaction between molecules and the substrate leads to a nonrandom orientation of SAMNs with respect to the substrate’s *** the case of graphite,the sixfold rotational symmetry of the substrate results in an equivalent rotational degeneracy in the orientation of *** this study,we explored how nanoconfinement,that is,the restriction of SAMN formation to nanometersized areas,known as nanocorrals,could impact and potentially alleviate the orientational degeneracy of SAMNs,with emphasis on the influence of molecule symmetry,size,and intermolecular *** this end,we investigated the orientation distribution of n-alkanes and functionalized alkanes within nanocorrals,which were fabricated using scanning tunneling microscopy lithography(nanoshaving).We observed lifting of orientational degeneracy for long alkanes,contrary to shorter alkanes,which did not exhibit this orientation ***,functionalized alkanes with hydrogen bonding groups demonstrated preferential alignment regardless of length,highlighting the significance of stabilizing intermolecular interactions in the alignment *** study discussed the underlying principles of the molecular packing process and shed light on the complexity of molecular self-assembly in nanoconfined spaces.

关键词： self-assembly confinement condition nanocorral orientation bias scanning tunneling microscopy

Recent applications of macrocycles in supramolecular catalysis

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Chinese Chemical Letters 2024年第4期35卷 132-141页

作者： Conghui Wang Lei Xu Zhenhua Jia Teck-Peng Loh College of Advanced interdisciplinary Science and Technology Henan University of TechnologyZhengzhou 450001China division of chemistry and Biological chemistry School of Chemistry Chemical Engineeringand BiotechnologyNanyang Technological UniversitySingapore 637371Singapore institute of Advanced Synthesis School of Chemistry and Molecular Engineering Nanjing Tech UniversityNanjing 211816China

Numerous supramolecular macrocycles have been utilized for developing catalysts by exploiting their specific molecular recognition and ability to form inclusion complexes through noncovalent interactions. The cyclic structure and modified functional groups of these macrocycles can influence substrate and transition state stability, as well as reaction selectivity. The inner cavities of these macrocycles are particularly beneficial, as they enable substrates to adopt preorganized arrangements and serve as versatile platforms for highly efficient supramolecular catalytic systems. This minireview provides an overview of recent advancements in supramolecular catalysis using various macrocycles, such as crown ethers, cyclodextrins,calixarenes, pillararenes, cucurbiturils, and other novel macrocycles.

关键词： Supramolecular catalysis Macrocycle Host-guest interactions Confinement Selectivity

Strategies for constructing seven-membered rings:Applications in natural product synthesis

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Chinese Chemical Letters 2024年第6期35卷 53-70页

作者： Peng Chen Lijuan Liang Yufei Zhu Zhimin Xing Zhenhua Jia Teck-Peng Loh College of Advanced interdisciplinary Science and Technology Henan University of TechnologyZhengzhou 450001China division of chemistry and Biological chemistry School of Chemistry Chemical Engineeringand BiotechnologyNanyang Technological UniversitySingapore 637371Singapore institute of Advanced Synthesis School of Chemistry and Molecular Engineering Nanjing Tech UniversityNanjing 211816China State Key Laboratory of Applied Organic chemistry Department of ChemistryLanzhou UniversityLanzhou 730000China

The seven-membered ring motifs are found in bioactive pharmaceuticals and a wide range of natural products,including alkaloids and terpenoids,which hold significant importance in synthetic chemistry and has garnered considerable attention from both academia and *** the challenges faced in the past decade,the total synthesis of natural products incorporating the non-aromatic cycloheptane skeletons remains a compelling ***,numerous elegant strategies for constructing the sevenmembered ring system have been successfully *** review focuses on the recent advancements in this field from 2017 to April 2023,highlighting key transformations utilized to construct the non-aromatic cycloheptane core structures and serves as a valuable guide for synthetic chemists engaged in the total synthesis of natural products containing seven-membered ring motifs.

关键词： Seven-membered rings Total synthesis Natural products Synthetic strategy Cycloheptane

Diagnostic and prognostic performances of GALAD score in staging and 1-year mortality of hepatocellular carcinoma: A prospective study

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World Journal of Gastroenterology 2024年第17期30卷 2343-2353页

作者： Oraphan Jitpraphawan Witchakorn Ruamtawee Mala Treewatchareekorn Supatsri Sethasine division of Gastroenterology and Hepatology Department of MedicineNavamindradhiraj UniversityDusit 10300BangkokThailand Clinical Research Center Research Facilitation DivisionNavamindradhiraj UniversityDusit 10300BangkokThailand division of Clinical chemistry and immunology Navamindradhiraj UniversityDusit 10300BangkokThailand

BACKGROUND The GALAD score has improved early hepatocellular carcinoma(HCC)detection *** role of the GALAD score in staging and predicting tumor characteristics or clinical outcome of HCC remains of particular *** To determine the diagnostic/prognostic performances of the GALAD score at various phases of initial diagnosis,tumor features,and 1-year mortality of HCC and compare the performance of the GALAD score with those of other serum *** This prospective,diagnostic/prognostic study was conducted among patients with newly diagnosed HCC at the liver center of Vajira *** patients had HCC staging allocation using the Barcelona Clinic Liver Cancer(BCLC)***,HCC etiology,and HCC features were *** and the GALAD score were obtained at *** performance of the GALAD score and biomarkers were prospectively *** Exactly 115 individuals were diagnosed with *** GALAD score increased with disease *** BCLC-0/A and BCLC-B/C/D,the GALAD score predicted HCC staging with an area under the curve(AUC)of 0.868(95%Ci:0.80–0.93).For identifying the curative HCC,the AUC of GALAD score was significantly higher than that of Alpha-fetoprotein(AFP)(0.753)and Lens culinaris agglutinin-reactive fraction of AFP-L3(0.706),and as good as that of Protein induced by vitamin K absence-ii(PiVKA-ii)(0.897).For detecting aggressive features,the GALAD score gave an AUC of 0.839(95%Ci:0.75–0.92)and significantly outperformed compared to that of AFP(0.761)and AFP-L3(0.697),with a trend of superiority to that of PiVKA-ii(0.772).The performance to predict 1-year mortality of GALAD score(AUC:0.711,95%Ci:0.60–0.82)was better than that of AFP(0.541)and as good as that of PiVKA-ii(0.736).The optimal cutoff value of GALAD score was≥6.83,with a specificity of 72.63%for exhibiting substantial reduction in the 1-year *** The GALAD model can diagnose HCC at the curative stage,includin

关键词： Alpha-fetoprotein Barcelona clinic liver cancer GALAD score Hepatocellular carcinoma Lens culinaris agglutinin-reactive fraction of alpha-fetoprotein Protein induced by vitamin K absence-ii

Peptidome data-driven comprehensive individualized monitoring of membranous nephropathy with machine learning

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Chinese Chemical Letters 2024年第5期35卷 402-406页

作者： Zixing Xu Ruiying Chen Chuanming Hao Qionghong Xie Chunhui Deng Nianrong Sun Department of Gastroenterology and Hepatology Zhongshan Hospitaland Department of ChemistryFudan UniversityShanghai 200433China division of Nephrology Huashan HospitalFudan UniversityShanghai 200040China School of chemistry and Chemical Engineering Nanchang UniversityNanchang 330031China

As the most common pathological type of nephrotic syndrome,membranous nephropathy(MN)presents diversity in progression trends,facing severe *** precise discrimination of MN from healthy people,other types of nephrotic syndrome or those with therapeutic remission has always been huge challenge in clinics,not to mention comprehensive individualized monitoring relied on minimally invasive molecular detection ***,we construct a functionalized pore architecture to couple with machine learning to aid all-round peptidome enrichment and data profiling from hundreds of human serum samples,and finally establish a set of defined peptide panel consisting of 12 specific feature *** addition to the realization of above-mentioned precise discrimination with more than 97%of sensitivity,88%of accuracy and f1 score,the simultaneously comprehensive individualized monitoring for MN can also be achieved,including conventionally screening diagnosis,congeneric distinction and prognostic *** work greatly advances the development of peptidome data-driven individualized monitoring means for complex diseases and undoubtedly inspire more devotion into molecular detection field.

关键词： Membranous nephropathy Serum peptidome Machine learning Disease diagnosis

Distinct molecular targets of ProEGCG from EGCG and superior inhibition of angiogenesis signaling pathways for treatment of endometriosis

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Journal of Pharmaceutical Analysis 2024年第1期14卷 100-114页

作者： Sze Wan Hung Massimiliano Gaetani Yiran Li Zhouyurong Tan Xu Zheng Ruizhe Zhang Yang Ding Gene Chi Wai Man Tao Zhang Yi Song Yao Wang Jacqueline Pui Wah Chung Tak Hang Chan Roman A.Zubarev Chi Chiu Wang Department of Obstetrics&Gynaecology The Chinese University of Hong KongHong KongChina division of physiological chemistry i Department of Medical Biochemistry and BiophysicsKarolinska InstitutetStockholmSE 17177Sweden Chemical Proteomics Core Facility Department of Medical Biochemistry and BiophysicsKarolinska InstitutetStockholmSE 17177Sweden Unit of Chemical Proteomics Science for Life Laboratory(SciLifeLab)StockholmSE 17177Sweden Center for Reproductive Medicine Henan Key Laboratory of Reproduction and GeneticsThe First Affiliated Hospital of Zhengzhou UniversityZhengzhou450003China Department of chemistry McGill UniversityMontrealH3A2K6Canada Department of Pharmacological&Technological chemistry I.M.Sechenov First Moscow State Medical UniversityMoscow119146Russia Reproduction and Development Li Ka Shing Institute of Health SciencesThe Chinese University of Hong KongHong KongChina School of Biomedical Sciences The Chinese University of Hong KongHong KongChina Chinese University of Hong Kong-Sichuan University Joint Laboratory in Reproductive Medicine The Chinese University of Hong KongHong KongChina

Endometriosis is a common chronic gynecological disease with endometrial cell implantation outside the *** is a major pathophysiology in *** previous studies have demonstrated that the prodrug of epigallocatechin gallate(ProEGCG)exhibits superior anti-endometriotic and anti-angiogenic effects compared to epigallocatechin gallate(EGCG).However,their direct binding targets and underlying mechanisms for the differential effects remain *** this study,we demonstrated that oral ProEGCG can be effective in preventing and treating ***,1D and 2D Proteome integral Solubility Alteration assay-based chemical proteomics identified metadherin(MTDH)and PX domain containing serine/threonine kinase-like(PXK)as novel binding targets of EGCG and ProEGCG,*** simulation and BioLayer interferometry were used to confirm their binding *** results showed that MTDH-EGCG inhibited protein kinase B(Akt)-mediated angiogenesis,while PXK-ProEGCG inhibited epidermal growth factor(EGF)-mediated angiogenesis via the EGF/hypoxia-inducible factor(HiF-1a)/vascular endothelial growth factor(VEGF)*** vitro and in vivo knockdown assays and microvascular network imaging further confirmed the involvement of these signaling ***,our study demonstrated that ProEGCG has superior therapeutic effects than EGCG by targeting distinct signal transduction pathways and may act as a novel antiangiogenic therapy for endometriosis.

关键词： Molecular targets ProEGCG EGCG Angiogenesis Treatment Endometriosis