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Frequency synthesis of forced opto-electronic oscillators at the X-band

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Chinese Optics Letters 2017年第1期15卷 40-44页

作者： T. Sun li. zhang A. K. Poddar U. L. Rohde A. S. Daryoush Department of ECE Drexel University Philadelphia PA 19104 USA Synergy Microwave Corp. Paterson NJ 07504 USA

Ultra-low phase noise performance is required for frequency agile local oscillators, which are the core for high resolution imagers, spectrum analyzers, and high speed data communications. A forced opto-electronic oscillator （OEO） benefits from frequency stabili.ation techniques for reali.ing a clean and low phase noise source at micro- wave and milli.eter wave frequencies. Forced oscillation techniques of self-injection locking and self-phase lock loop are combined to provide an ultra-low oscillator phase noise both close-in and far-away from the carrier frequency, while a tunable yttrium iron garnet microwave filter combined with a wavelength tuned transversal filter are employed to implement both coarse and fine frequency tuning for a tunable X-band OEO. A phase noise of -137 dBc/Hz at an offset frequency of 10 kHz is achieved covering the frequencies of 9 to 11 GHz with a fine frequency tuning resolution of 44 Hz/pm and coarse tuning of 25 MHz/mA. Moreover, the long term stabili.y of the output signal is tested, and a maximum frequency drift of 2 kHz is measured within 60 min for the X-band synthesizer.

关键词： Fiber optics li.ks and subsystems Radio frequency photonics Oscillators

Preparation of silver nanoparticles through the reduction of straw-extracted li.nin and its antibacterial hydrogel

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International Journal of Minerals,Metallurgy and Materials 2025年第2期32卷 504-514页

作者： Lou zhang Shuo li.Fu Tang Jingkai zhang Yuetong Kang Hean zhang li.ong li State Key Laboratory for Advanced Metals and Materials School of Materials Science and EngineeringUniversity of Science and Technology BeijingBeijing 100083China

Silver nanoparticles(Ag NPs)have attracted attention in the field of biomaterials due to their excellent antibacterial ***,the reducing and stabili.ing agents used for the chemical reduction of Ag NPs are usually toxic and may cause water *** this work,Ag NPs(31.2 nm in diameter)were prepared using the extract of straw,an agricultural waste,as the reducing and stabili.ing *** analysis revealed that the straw extract contained li.nin,the structure of which possesses phenoli. hydroxyl and methoxy groups that facili.ate the reduction of silver salts into Ag *** surfaces of Ag NPs were negatively charged due to the encapsulation of a thin layer of li.nin molecules that prevented their *** the prepared Ag NPs were added to the precursor solution of acrylamide,free radical polymerization was triggered without the need for extra heating or li.ht irradiation,resulting in the rapid formation of an Ag NP-polyacrylamide composite *** inhibition zone test proved that the composite hydrogel possessed excellent antibacterial abili.y due to the presence of Ag *** prepared hydrogel may have potential appli.ations in the fabrication of biomedical materials,such as antibacterial dressings.

关键词： silver nanoparticles hydrogel straw extraction antibacterial

Depression mechanism of sulfite ions on sphalerite and Pb^(2+)activated sphalerite in the flotation separation of galena from sphalerite

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International Journal of Minerals,Metallurgy and Materials 2025年第2期32卷 335-345页

作者： Feng zhang Chenyang zhang li.li. Wu Wei Sun Hongli.ng zhang Jianhua Chen Yong Pei Songjiang li Engineering Research Center of Ministry of Education for Carbon Emission Reduction in Metal Resource Exploitation and Utili.ation Hunan International Joint Research Center for Efficient and Clean Utilization of Critical Metal Mineral ResourcesSchool of Minerals Processing and BioengineeringCentral South UniversityChangsha 410083China State Key Laboratory of Mineral Processing Beijing General Research Institute of Mining&MetallurgyBeijing 100160China Hunan Provincial Key Laboratory of Micro&Nano Materials Interfaces Science College of Chemistry and Chemical EngineeringCentral South UniversityChangsha 410083China School of Resources Environment and MaterialsGuangxi UniversityNanning 530004China Department of Chemistry Xiangtan UniversityXiangtan 411105China China Railway Resource Group Co.Ltd Beijing 102300China

The depression mechanism of sulfite ions on sphalerite and Pb^(2+)activated sphalerite in the flotation separation of galena from sphalerite still lacked in-depth ***,the depression mechanism of sulfite ions on sphalerite and Pb^(2+)activated sphalerite in the flotation separation of galena from sphalerite was further systematically investigated with experiments and density functional theory(DFT)*** X-ray photoelectric spectroscopy(XPS)results,DFT calculation results,and frontier molecular orbital analysis indicated that sulfite ions were difficult to be adsorbed on sphalerite surface,suggesting that sulfite ions achieved depression effects on sphalerite through other non-adsorption ***,the oxygen content in the surface of sphalerite treated with sulfite ions in creased,which enhanced the hydrophili.ity of the sphalerite and further increased the difference in hydrophili.ity between sphalerite and ***,sulfite ions were chelated with lead ions to form PbSO_(3)in *** hydrophili. PbSO_(3)was more easily adsorbed on sphalerite than *** interaction between sulfite ions and lead ions could effectively inhibit the activation of *** addition the UV spectrum showed that after adding sulfite ions,the peak of perxanthate in the sphalerite treated xanthate solution was significantly stronger than that in the galena with xanthate solution,indicating that xanthate interacted more readily with sulfite ions and oxygen mo lecules within the sphalerite system,leading to the formation of ***,sulfite ions hardly depressed the flotation of ga lena and could promote the flotation of galena to some *** study deepened the understanding of the depression mechanism o sulfite ions on sphalerite and Pb^(2+)activated sphalerite.

关键词： sphalerite galena sulfite ion density functional theory depression mechanism

Microstructural evolution during the progressive transformation-induced plasticity effect in a Fe-0.1C-5Mnmedium manganese steel

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International Journal of Minerals,Metallurgy and Materials 2025年第2期32卷 369-379页

作者： Mei zhang Wenhao li.Yangfei Chen Yang Jiang Xiaofei Guo Han Dong School of Materials Science and Engineering Shanghai UniversityShanghai 200444China State Key Laboratory of Advanced Special Steel Shanghai UniversityShanghai 200444China

The microstructural evolution of a cold-rolled and intercritical annealed medium-Mn steel(Fe-0.10C-5Mn)was investigated during uniaxial tensile ***-situ observations under scanning electron microscopy,transmission electron microscopy,and X-ray diffraction analysis were conducted to characterize the progressive transformation-induced plasticity process and associated fracture initiation *** findings were discussed with the local strain measurements via digital image *** results indicated that Lüders band formation in the steel was li.ited to 1.5%strain,which was mainly due to the early-stage martensitic phase transformation of a very small amount of the less stable large-sized retained austenite(RA),which led to locali.ed stress concentrations and strain hardening and further retardation of *** small-sized RA exhibited high stabili.y and progressively transformed into martensite and contributed to a stably extended Portevin-Le Chateli.r *** volume fraction of RA gradually decreased from 26.8%to 8.2%prior to *** the late deformation stage,fracture initiation primarily occurred at the austenite/martensite and ferrite/martensite interfaces and the ferrite phase.

关键词： medium-Mn steel retained austenite progressive transformation-induced plasticity effect local strain fracture initiation

Small extracellular vesicles derived from cerebral endotheli.l cells with elevated microRNA 27a promote ischemic stroke recovery

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Neural Regeneration Research 2025年第1期20卷 224-233页

作者： Yi zhang Zhongwu li. Michael Chopp Michael Millman Yanfeng li.Pasquale Cepparulo Amy Kemper Chao li.li.zhang Zheng Gang zhang Department of Neurology Henry Ford HospitalDetroitMIUSA Department of Physics Oakland UniversityRochesterMIUSA Department of Pathology Henry Ford HospitalDetroitMIUSA Division of Pharmacology Department of NeuroscienceReproductive and Dentistry SciencesSchool of MedicineUniversity of Naples“Federico Ⅱ”NaplesItaly

Axonal remodeli.g is a critical aspect of ischemic brain repair processes and contributes to spontaneous functional *** previous in vitro study demonstrated that exosomes/small extracellular vesicles(sEVs)isolated from cerebral endotheli.l cells(CEC-sEVs)of ischemic brain promote axonal growth of embryonic cortical neurons and that microRNA 27a(miR-27a)is an elevated miRNA in ischemic *** the present study,we investigated whether normal CEC-sEVs engineered to enrich their levels of miR-27a(27a-sEVs)further enhance axonal growth and improve neurological outcomes after ischemic stroke when compared with treatment with non-engineered CEC-sEVs.27a-sEVs were isolated from the conditioned medium of healthy mouse CECs transfected with a lentiviral miR-27a expression *** EVs isolated from CECs transfected with a scramble vector(Scra-sEVs)were used as a *** male mice were subjected to permanent middle cerebral artery occlusion and then were randomly treated with 27a-sEVs or *** array of behavior assays was used to measure neurological *** with treatment of ischemic stroke with Scra-sEVs,treatment with 27a-sEVs significantly augmented axons and spines in the peri-infarct zone and in the corticospinal tract of the spinal grey matter of the denervated side,and significantly improved neurological *** vitro studies demonstrated that CEC-sEVs carrying reduced miR-27a aboli.hed 27a-sEV-augmented axonal *** analysis revealed that 27a-sEVs systemically administered preferentially locali.ed to the pre-synaptic active zone,while quantitative reverse transcription-polymerase chain reaction and Western Blot analysis showed elevated miR-27a,and reduced axonal inhibitory proteins Semaphorin 6A and Ras Homolog Family Member A in the peri-infarct *** of the Clathrin-dependent endocytosis pathway substantially reduced neuronal internali.ation of *** data provide evidence that 27a-sEVs have

关键词： axonal remodeli.g cerebral endotheli.l cells exosomes miR-27a mitochondria Semaphorin 6A small extracellular vesicles stroke

Multiphase reaction spinning of high-temperature resistant weavable SiO_(2)-Kevlar hybrid aerogel fibers

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Nano Research 2025年第1期18卷 424-433页

作者： Yunna Chen Wenlu zhang Qingyang li.Wenbin li.Chong He School of Textile Science and Engineering Wuhan Textile UniversityWuhan 430200China State Key Laboratory of New Textile Materials and Advanced Processing Technologies Wuhan Textile UniversityWuhan 430200China

Advanced aerogel fibers possess numerousadvantages amalgamating the attributes of aerogels and fibermaterials, rendering them invaluable in the realm of thermalmanagement and regulation. However, the achievement ofrobust mechanical properties and increased temperaturestabili.y is still a major challenge for the majority of aerogelfibers. Herein, SiO_(2)-Kevlar hybrid aerogel fibers with bioniccore-shell structure were prepared by reaction spinning andweaved into fabric. Kevlar nanowires dispersion is pumpedinto a bath comprising a self-synthesized sili.a sol, whichfacili.ates the hybridization of biphasic aerogels through thegel reaction. Precise control over the diameter (200-800 μm)and structure of the wet gel fibers was achieved throughmeticulous adjustment of the spinning solution composition and spinning parameters. Subsequent freeze-drying processfacili.ates the formation of a core-shell hybrid structure, in which the SiO_(2) aerogel layer effectively encapsulate the Kevlaraerogel core fiber. Taking full advantage of the mechanical properties of the Kevlar core fiber, the resulting SiO_(2)-Kevlaraerogel fibers exhibit commendable weaving characteristics (51.8 MPa). Furthermore, SiO_(2)-Kevlar aerogel fabrics exhibitenhanced thermal insulation characteristics with a thermal conductivity of 0.037 W/(m·K). As a result of the presence ofexternal SiO_(2) aerogel layer, the overall temperature resistance performance of the SiO_(2)-Kevlar fabric reach up to 700 ℃.

关键词： aerogel fibers SiO_(2)aerogel Kevlar aerogel reaction spinning thermal protective performance

Gamma-glutamyl transferase 5 overexpression in cerebrovascular endotheli.l cells improves brain pathology,cognition,and behavior in APP/PS1 mice

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Neural Regeneration Research 2025年第2期20卷 533-547页

作者： Yanli.zhang Tian li.Jie Miao Zhina zhang Mingxuan Yang Zhuoran Wang Bo Yang Jiawei zhang Haiting li.Qiang Su Junhong Guo Department of Neurology First Hospital of Shanxi Medical UniversityTaiyuanShanxi ProvinceChina Department of Neurology Sixth Hospital of Shanxi Medical University(General Hospital of Tisco)TaiyuanShanxi ProvinceChina Department of Physiology Key Laboratory of Cellular PhysiologyMinistry of EducationShanxi Medical UniversityTaiyuanShanxi ProvinceChina Department of Hernia and Abdominal Wall Surgery Shanxi Bethune HospitalShanxi Academy of Medical SciencesTongji Shanxi HospitalThird Hospital of Shanxi Medical UniversityTaiyuanShanxi ProvinceChina Department of Laboratory Medicine of Fenyang College Shanxi Medical UniversityFenyangShanxi ProvinceChina

In patients with Alzheimer’s disease,gamma-glutamyl transferase 5(GGT5)expression has been observed to be downregulated in cerebrovascular endotheli.l ***,the functional role of GGT5 in the development of Alzheimer’s disease remains *** study aimed to explore the effect of GGT5 on cognitive function and brain pathology in an APP/PS1 mouse model of Alzheimer’s disease,as well as the underlying *** observed a significant reduction in GGT5 expression in two in vitro models of Alzheimer’s disease(Aβ_(1-42)-treated hCMEC/D3 and bEnd.3 cells),as well as in the APP/PS1 mouse ***,injection of APP/PS1 mice with an adeno-associated virus encoding GGT5 enhanced hippocampal synaptic plasticity and mitigated cognitive ***,increasing GGT5 expression in cerebrovascular endotheli.l cells reduced levels of both soluble and insoluble amyloid-βin the brains of APP/PS1 *** effect may be attributable to inhibition of the expression ofβ-site APP cleaving enzyme 1,which is mediated by nuclear factor-kappa *** findings demonstrate that GGT5 expression in cerebrovascular endotheli.l cells is inversely associated with Alzheimer’s disease pathogenesis,and that GGT5 upregulation mitigates cognitive deficits in APP/PS1 *** findings suggest that GGT5 expression in cerebrovascular endotheli.l cells is a potential therapeutic target and biomarker for Alzheimer’s disease.

关键词： Alzheimer’s disease amyloid-β APP/PS1 mice cerebrovascular endotheli.l cells cognitive deficits gamma-glutamyl transferase 5 neurovascular unit nuclear factor‐kappa B synaptic plasticity β-site APP cleaving enzyme 1

Fluorinated poly(p-triphenylene isatin) anion exchange membranes based on hydrophili. hydroxyl side chain modulation for fuel cells

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Journal of Energy Chemistry 2025年第1期100卷 702-709页

作者： Yiman Gu Yanchao zhang Zhanyu li.Yijia Lei Baozeng Sun Xiaoyu Yu Zhe Wang College of Chemistry and li.e Science Changchun University of Technology College of Chemical Engineering Changchun University of Technology School of Materials Science and Engineering Changchun University of Technology Key Laboratory of Advanced Functional Polymer Membrane Materials of Jili. Province

The development of alkali.e fuel cells is moving forward at an accelerated pace,and the appli.ation of ether-free bonded polymers to anion exchange membranes （AEMs） has been widely ***,the question of the“trade-off”between AEM ionic conductivity and dimensional stabili.y remains *** strategy of inducing microphase separation to improve the performance of AEM has attracted much attention recently,but the design of optimal molecular structures is still being ***,this work introduced different ratios of 3-bromo-1,1,1-trifluoroacetone （x=40,50,and 60） into the main chain of poly（p-terphenylene isatin）.Because fluorinated groups have excellent hydrophobicity,hydrophili. hydroxyl-containing side chains are introduced to jointly adjust the formation of phase separation *** results show that PTI-PTF50-NOH AEM with the appropriate fluorinated group ratio has the best ionic conductivity and alkali.stabili.y under the combined effect of *** has an ionic conductivity of 133.83 mS cm-1at 80°*** addition,the OH-conductivity remains at 89%of the initial value at 80°C and 3 M KOH for 1056 h of *** cell polarization curve based on PTI-PTF50-NOH shows a power density of 734.76 mW cm-2at a current density of 1807.7 mA cm-2.

关键词： Anion exchange membranes Poly(p-terphenylene isatin) Hydrophili.-hydrophobic phase separation Fluorinated group

Return to work in young and middle-aged colorectal cancer survivors:Factors influencing self-efficacy,fear,resili.nce,and financial toxicity

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World Journal of Gastroenterology 2025年第1期31卷 79-92页

作者： Dan Hu Yue li.Hua zhang li.n-li.n Wang Wen-Wen li. Xin Yang Ming-Zhao Xiao Hao-li.g zhang Juan li Department of Nursing The First Affiliated Hospital of Chongqing Medical UniversityChongqing 400016China Department of Nursing National Clinical Research Center for Child Health and DisordersMinistry of Education Key Laboratory of Child Development and DisordersChildren’s Hospital of Chongqing Medical UniversityChongqing 400014China Department of Gastrointestinal Surgery The First Affiliated Hospital of Chongqing Medical UniversityChongqing 400016China Department of Biomedical Science Advanced Medical and Dental InstituteUniversity Sains MalaysiaPenang 13200Malaysia Academic Affairs Office The First Affiliated Hospital of Chongqing Medical UniversityChongqing 400016China

BACKGROUND Return to work(RTW)serves as an indication for young and middle-aged colorectal cancer(CRC)survivors to resume their normal social ***,these survivors encounter significant challenges during their RTW ***,scientific research is necessary to explore the barriers and facili.ating factors of returning to work for young and middle-aged CRC *** To examine the current RTW status among young and middle-aged CRC survivors and to analyze the impact of RTW self-efficacy(RTW-SE),fear of progression(FoP),eHealth li.eracy(eHL),family resili.nce(FR),and financial toxicity(FT)on their RTW *** A cross-sectional investigation was adopted in this *** September 2022 to February 2023,a total of 209 participants were recruited through a convenience sampli.g method from the gastrointestinal surgery department of a class A tertiary hospital in *** investigation utili.ed a general information questionnaire alongside scales assessing RTW-SE,FoP,eHL,FR,and *** analyze the factors that influence RTW outcomes among young and middle-aged CRC survivors,Cox regression modeli.g and Kaplan-Meier survival analysis were *** A total of 43.54%of the participants successfully returned to work,with an average RTW time of 100 *** regression univariate analysis revealed that RTW-SE,FoP,eHL,FR,and FT were significantly different between the non-RTW and RTW groups(Pli.ating their timely reintegration into mainstream society.

关键词： Return to work Colorectal neoplasms Return-to-work self-efficacy Fear of progression Family resili.nce Financial toxicity