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Finite element simulation of Rayleigh surface acoustic wave in(100)AlN/(100)ZnO/diamond layered structure

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Optoelectronics Letters 2023年第12期19卷 732-738页

作者： ZHANG Zeyu qian jin qian lirong WEN Fujun WANG litian li Cuiping Tianjin Key Laboratory of Film Electronic and Communication Devices School of Integrated Circuit Science and EngineeringTianjin University of TechnologyTianjin 300384China Engineering Research Center of Optoelectronic Devices&Communication Technology School of Integrated Circuit Science and EngineeringTianjin University of TechnologyTianjin 300384China

With the rapid development of the fifth-generation(5G)wireless system,the explosive growth of transmitted data raises higher requirements for high-performance surface acoustic wave(SAW)devices as filters and duplexers.(100)AlN/(100)ZnO/diamond layered structures are theoretically simulated by finite element method(FEM)to investigate the Rayleigh SAW propagation properties,including phase velocity,electromechanical coupling coefficient K^(2),and temperature coefficient of frequency(TCF).Three types of layered structures with different interdigital transducers(IDTs)arrangements,which are IDTs/(100)AlN/(100)ZnO/diamond,(100)AlN/IDTs/(100)ZnO/diamond,and(100)AlN/(100)ZnO/IDTs/diamond structures,are considered in the simulations.The results show that the Sezawa mode exhibits larger K^(2)than the other modes.We found that the(100)AlN/IDTs/(100)ZnO/diamond structure exhibited better SAW properties,including high K^(2)and appropriate phase velocity.

关键词： element wave structure

Leaching behavior and mineralogical evolution of vanadium released from sodium roasted-acid leaching tailing of vanadium slag

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Journal of Iron and Steel Research(International) 2022年第5期29卷 772-782页

作者： Bao liu jin li qian-qian Ren Shuang Cai Xue Yang Ya-nan Zeng Jun-guo li College of Metallurgy and Energy North China University of Science and TechnologyTangshan063210HebeiChina

The sodium roasted-acid leaching tailing(SRALT)of vanadium slag with a certain amount of vanadium exhibits potential environmental risk.To investigate the leaching behavior of vanadium from the SRALT,neutral batch leaching tests were performed.The evolution of vanadium concentration,pH,redox potential(Eh),dissolved oxygen,and conductivity as a function of time was measured.Pourbaix diagrams of V–H2O system with different vanadium concentrations were obtained to identify the ionic speciation of vanadium in leachate.X-ray diffraction,X-ray photoelectron spectroscopy,field emission-scanning electron microscopy,and thermogravimetry–differential scanning calorimetry analysis were conducted to investigate the mineralogical evolution of the SRALT during the leaching process.It was found that the major minerals of the original SRALT are titanomagnetite,spinel,olivine,and augite.The valence states of V existing in the original SRALT are V^(3+)and V^(5+).The pH and Eh values of the obtained leachates are 10.00–10.58 and(−43)–(+67)mV,respectively.In this pH and Eh region,the released vanadium is mainly present as HVO_(4)^(2−).The FeOOH and CaCO_(3)would form during the leaching process.The HVO_(4)^(2−)would be mainly adsorbed by the FeOOH and slightly incorporated into the CaCO_(3),resulting in the decline in the vanadium concentration.The vanadium concentration above 27 mg L^(−1)and the dissolved oxygen value below 5.0 mg L^(−1)can be obtained after a short leaching period.As a V(V)-releasing and oxygen-depleting substance,the leaching toxicity of the SRALT should not be ignored.

关键词： Vanadium Vanadium slag Tailing Leaching toxicity Mineralogical analysis

Graphitic carbon nitride loaded with bismuth nanoparticles displays antibacterial photocatalytic activity

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Rare Metals 2022年第5期41卷 1570-1582页

作者： Hui Zhang ling li qian-qian li Tao Ma Jia-Qi Gao jin-Bo Xue Shuang Gao Department of Plastic Surgery Second Hospital of Shanxi Medical UniversityTaiyuan 030001China Key Laboratory of Interface Science and Engineering in Advanced Materials Taiyuan University of TechnologyMinistry of EducationTaiyuan 030024China Department of Materials and Earth Sciences Technical University of DarmstadtDarmstadt 64287Germany

Metal-free graphitic carbon nitride nanomaterials have been widely applied in the medical antibacterial field owing to their high anisotropy, excellent stability,satisfactory biocompatibility, and non-toxicity. Herein, Bi/C_(3)N_(4) nanocomposites were successfully constructed by hydrothermal method followed by loading bismuth on the surface of graphite carbon nitride. Bi nanospheres were tightly combined with the layered g-C_(3)N_(4) surface to promote effective separation of photo-induced charges, which results in the Bi/C_(3)N_(4) composite material that exhibited excellent photocatalytic activity under visible light. In addition, the surface plasmon resonance characteristics of semi-metal Bi further enhanced the visible-light absorption of the Bi/C_(3)N_(4). However, excessive Bi may inhibit the light-trapping ability of Bi/C_(3)N_(4).1.0% Bi/C_(3)N_(4) demonstrates excellent bactericidal efficiency as high as 96.4% against Escherichia coli(E. coli), which is attributed to the promotion of the production of reactive oxidative species.The enhanced mechanism of Bi/C_(3)N_(4) synergistically achieving enhanced photocatalytic antibacterial activity under the coupling of multiple advantages was clarified,providing theoretical guidance for its application in the field of water disinfection and antibacterial treatment.

关键词： Carbon nitride Bi nanospheres Schottky barrier ROS Photocatalytic antibacterial

Astragaloside Ⅳ for Heart Failure: Preclinical Evidence and Possible Mechanisms, A Systematic Review and Meta-Analysis

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Chinese Journal of Integrative Medicine 2023年第7期29卷 626-633页

作者： li Xing-xing li Dong CUI Xiao-yun ZHOU Kun liU jing LU jin-jin WU Yang liN qian li Yan Department of Cardiology Dongfang HospitalBeijing University of Chinese MedicineBeijing100078China Department of Cardiology Dongzhimen HospitalBeijing University of Chinese MedicineBeijing100700China

Objective:To explore the cardioprotective effects of astragaloside Ⅳ(AS-Ⅳ) in heart failure(HF).Methods:PubMed,Excerpta Medica Database(EMBASE),Cochrane library,Web of Science,Wanfang Database,Chinese Bio-medical literature and Retrieval System(SinoMed),China Science and Technology Journal Database(VIP),and China National Knowledge Infrastructure(CNKI) were searched from inception to November 1,2021for animal experiments to explore AS-Ⅳ in treating HF in rats or mice. The left ventricular ejection fraction(LVEF),left ventricular fractional shortening(LVFS),left ventricular end-diastolic dimension(LVEDD),left ventricular endsystolic dimension(LVESD),left ventricular weight-to-body weight(LVW/BW) and B-type brain natriuretic peptide(BNP) were recorded.The qualities of included studies were assessed by the risk of bias according to the Cochrane handbook.Meta-analysis was performed using Stata 13.0.Results:Twenty-one articles involving 558 animals were considered.Compared with the control group,AS-Ⅳ improved cardiac function,specifically by increasing LVEF(mean difference(MD)=6.97,95% confidence interval(CI)=5.92 to 8.03,Plinically validated in the future.

关键词： astragaloside IV heart failure pre-clinical evidence systematic review

Glucagon-like peptide-1/glucose-dependent insulinotropic polypeptide dual receptor agonist DA-CH5 is superior to exendin-4 in protecting neurons in the 6-hydroxydopamine rat Parkinson model

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Neural Regeneration Research 2021年第8期16卷 1660-1670页

作者： ling-Yu Zhang qian-qian jin Christian Hölscher lin li Gerontology Institute Shanxi Medical UniversityTaiyuanShanxi ProvinceChina Department of Forensic Pathology Shanxi Medical UniversityTaiyuanShanxi ProvinceChina Department of Neurology Second HospitalShanxi Medical UniversityTaiyuanShanxi ProvinceChina Research and Experimental Center Henan University of Chinese MedicineZhengzhouHenan ProvinceChina

Patients with Parkinson's disease(PD) have impaired insulin signaling in the brain. Incretin hormones, including glucagon-like peptide-1(GLP-1) and glucose-dependent insulinotropic polypeptide(GIP), can re-sensitize insulin signaling. In a recent phase II clinical trial, the first GLP-1 mimic, exendin-4, has shown reliable curative effect in patients with PD. DA-CH5 is a novel GLP-1/GIP receptor unimolecular coagonist with a novel peptide sequence added to cross the blood-brain barrier. Here we showed that both exendin-4 and DA-CH5 protected against 6-hydroxydopamine(6-OHDA) cytotoxicity, inhibited apoptosis, improved mitogenesis and induced autophagy flux in SH-SY5Y cells via activation of the insulin receptor substrate-1(IRS-1)/alpha serine/threonine-protein kinase(Akt)/c AMP response element-binding protein(CREB) pathway. We also found that DA-CH5(10 nmol/kg) daily intraperitoneal administration for 30 days post-lesion alleviated motor dysfunction in rats and prevented stereotactic unilateral administration of 6-OHDA induced dopaminergic neurons loss in the substantia nigra pars compacta. However, DA-CH5 showed curative effects in reducing the levels of α-synuclein and the levels of pro-inflammatory cytokines(tumor necrosis factor-α, interleukin-1β). It was also more effective than exendin-4 in inhibiting apoptotic process and protecting mitochondrial functions. In addition, insulin resistance was largely alleviated and the expression of autophagy-related proteins was upregulated in PD model rats after DA-CH5 treatment. These results in this study indicate DA-CH5 plays a therapeutic role in the 6-OHDAunilaterally lesioned PD rat model and is superior to GLP-1 analogue exendin-4. The study was approved by the Animal Ethics Committee of Shanxi Medical University of China.

关键词： neurodegenerative disease Parkinson's disease insulin resistance inflammation GLP-1/GIP receptor unimolecular co-agonist

Dendronized Polymers with High FTC-chromophore Loading Density:Large Second-order Nonlinear Optical Effects, Good Temporal and Thermal Stability

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Chinese Journal of Polymer Science 2020年第2期38卷 118-125,I0005页

作者： Meng jin Zhao-Chen Zhu Qiu-Yan liao qian-qian li Zhen li Department of Chemistry Sauvage Center for Molecular SciencesWuhan UniversityWuhan 430072China Institute of Molecular Aggregation Science Tianjin UniversityTianjin 300072China

In this study,two new dendronized nonlinear optical(NLO)polymers were synthesized with high FTC chromophore loading density by introduction of high generation chromophore dendrons on the side chains.Due to their suitable molecular weights,both of them possessed good solubility in common solvents.They also inherited the advantages of dendrimers(large NLO coefficient),especially for PG2 whose NLO coefficient d33 value was as high as 282 pm·V^–1.Also,PG2 had a good temporal stability with 80%of its maximum value being retained at the temperature as high as 129℃.

关键词： Second-order nonlinear optics Dendronized polymers Chromophore

Mechanical and tribological performance of AlCr_(0.5)NbTa_(x)Ti_(4-x)(x=0,0.5,1)refractory high-entropy alloys

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Journal of Materials Science & Technology 2023年第25期156卷 241-253页

作者： Haozhe li Xiaolin li Chi jin qian li qiang Ma Ke Hua Haifeng Wang Weimin liu State Key Laboratory of Solidification Processing Center of Advanced Lubrication and Seal MaterialsNorthwestern Polytechnical UniversityXi'an 710072China State Key Laboratory of Solid Lubrication Lanzhou Institute of Chemical PhysicsChinese Academy of SciencesLanzhou 730000China

The tribological behavior of AlCr_(0.5)NbTa_(x)Ti_(4-x)(x=0,0.5,and 1)refractory high-entropy alloys was systematically investigated from room temperature to 800℃.The relationship between the alloy composition,microstructure,mechanical properties,and tribological performance was analyzed.The results show that all three alloys have a body-centered cubic(bcc)single-phase structure.The Ta addition enhances solid solution strengthening and increases the melting point that would resist high-temperature thermal softening.As a result,high-temperature strength is enhanced considerably,the coefficients of friction(COF)and wear rates of the alloys are reduced considerably at elevated temperatures,demonstrating excellent friction-reducing and anti-wear properties,e.g.,the COF and wear rate of AlCr_(0.5) NbTaTi_(3) alloy at 800℃ are 0.34 and 4.40×10^(-7) mm^(3) N^(-1) m^(-1),respectively.The excellent wear resistance at high temperatures can be attributed to the formation of an oxide-tribo layer(Ta_(2)O_(5) and TiO_(2))with ultrafine-grained layers and good high-temperature mechanical properties.

关键词： Refractory high entropy alloys High temperature Mechanical properties Wear resistance Oxide-tribo layer

Pyrrolizidine alkaloids-induced hepatic sinusoidal obstruction syndrome: Pathogenesis, clinical manifestations, diagnosis,treatment, and outcomes

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World Journal of Gastroenterology 2019年第28期25卷 3753-3763页

作者： Xiao-qian Yang jin Ye Xin li qian li Yu-Hu Song Division of Gastroenterology Union Hospital Tongji Medical college Huazhong University of Science and Technology Wuhan 430022 Hubei Province China Department of Radiology Union Hospital Tongji Medical college Huazhong University of Science and technology Wuhan 430022 Hubei Province China

Hepatic sinusoidal obstruction syndrome (HSOS) can be caused by the intake of pyrrolizidine alkaloids (PAs). To date, PAs-induced HSOS has not been extensively studied. In view of the difference in etiology of HSOS between the West and China, clinical profiles, imaging findings, treatment, and outcomes of HSOS associated with hematopoietic stem cell transplantation or oxaliplatin might be hardly extrapolated to PAs-induced HSOS. Reactive metabolites derived from PAs form pyrrole-protein adducts that result in toxic destruction of hepatic sinusoidal endothelial cells. PAs-induced HSOS typically manifests as painful hepatomegaly, ascites, and jaundice. Laboratory tests revealed abnormal liver function tests were observed in most of the patients with PAs-induced HSOS. In addition, contrast computed tomography and magnetic resonance imaging scan show that patients with PAs-induced HSOS have distinct imaging features, which reveal that radiological imaging provides an effective noninvasive method for the diagnosis of PAs-induced HSOS. liver biopsy and histological examination showed that PAs-induced HSOS displayed distinct features in acute and chronic stages. Therapeutic strategies for PAs-induced HSOS include rigorous fluid management, anticoagulant therapy, glucocorticoids, transjugular intrahepatic portosystemic shunt, liver transplantation, etc. The aim of this review is to describe the pathogenesis, clinical profiles, diagnostic criteria, treatment, and outcomes of PAs-induced HSOS.

关键词： Hepatic sinusoidal obstruction syndrome Pyrrolizidine alkaloids Hepatic sinusoidal endothelial cells Pyrrole-protein adducts Diagnostic criteria Symptomatic treatment Anticoagulant therapy

Are allometric model parameters of aboveground biomass for trees phylogenetically constrained?

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Plant Diversity 2023年第2期45卷 229-233页

作者： Xing-Zhao Huang Fang-Bing li Zi-Xuan Wang Yi jin Hong qian School of Forestry&Landscape of Architecture Anhui Agricultural UniversityHefei 230036China State Key Laboratory of Vegetation and Environmental Change Institute of BotanyChinese Academy of SciencesBeijing 100093China Key Laboratory of National Forestry and Grassland Administration on Biodiversity Conservation in Karst Mountainous Areas of Southwestern China Guizhou Normal UniversityGuiyang 550025China Research and Collections Center Illinois State Museum1011 East Ash StreetSpringfieldIL 62703USA

Knowledge of which biological and functional traits have,or lack,phylogenetic signal in a particular group of organisms is important to understanding the formation and functioning of biological communities.Allometric biomass models reflecting tree growth characteristics are commonly used to predict forest biomass.However,few studies have examined whether model parameters are constrained by phylogeny.Here,we use a comprehensive database(including 276 tree species) compiled from 894 allometric biomass models published in 302 articles to examine whether parameters a and b of the model W=aD~b(where W stands for aboveground biomass,D is diameter at breast height) exhibit phylogenetic signal for all tree species as a whole and for different groups of tree species.For either model parameter,we relate difference in model parameter between different tree species to phylogenetic distance and to environmental distance between pairwise sites.Our study shows that neither model parameter exhibits phylogenetic signals(Pagel's λ and Blomberg's K both approach zero).This is the case regardless of whether all tree species in our data set were analyzed as a whole or tree species in different taxonomic groups(gymnosperm and angiosperm),leaf duration groups(evergreen and deciduous),or ecological groups(tropical,temperate and boreal) were analyzed separately.Our study also shows that difference in each parameter of the allometric biomass model is not significantly related to phylogenetic and environmental distances between tree species in different sites.

关键词： Allometric biomass model Pagel'sλ Blomberg's K Phylogenetic constraint