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Enhanced memristor performance via coupling effect of oxygen vacancy and ferroelectric polarization

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Journal of Materials Science & Technology 2024年第4期171卷 139-146页

作者： zhi yun Yue zhi Dong Zhang Zhan Jie Wang Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China School of Materials Science and Engineering University of Science and Technology of ChinaShenyang 110016China School of Materials Science and Engineering Shenyang University of TechnologyShenyang 110870China

As a new type of nonvolatile memory,the resistive memristor has broad application prospects in in-formation storage and neural computing based on its excellent resistive switching(RS)performance.At present,it is still a great challenge to improve both ferroelectric polarization and leakage current to achieve a high RS on/offratio of ferroelectric memristors.Herein,epitaxial Pb(Zr_(0.40)Ti_(0.60))O_(3)(PZT)thin films with low content Ca doping were deposited on the Nb:SrTiO_(3)substrate to prepare PCZT/NSTO het-erostructures and their RS behaviors were studied.The research findings show that compared with pure PZT film,the ferroelectric polarization of 1-mol%-Ca-doped PZT film is slightly improved,while the leak-age current is increased by three orders of magnitude.Therefore,the RS on/offratio reaches 2.5×10^(5),about three orders of magnitude higher than pure PZT films.The theoretical analysis reveals that the RS behavior of PCZT/NSTO heterostructures is controlled by the PCZT/NSTO interfacial barrier and the space charge-limited current mechanism.Our results demonstrate that the ferroelectricity and electricity of ferroelectric thin films can be improved simultaneously by doping low-content Ca ions to increase the RS performance,which provides a good reference for the development of high-performance ferroelectric memristor devices.

关键词： Ferroelectric memristor Ca-doped PZT Ferroelectric polarization Oxygen vacancies Resistive switching

A Unprecedented Rare-Earth Molecular Ferroelectrics with High Curie temperature, Large Spontaneous Polarization, Switchable SHG Effect and Strong Photoluminescence

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A Unprecedented Rare-Earth Molecular Ferroelectrics with Hig...

Clinical efficacy of femtosecond laser-assisted phacoemulsification in diabetic cataract patients

中国稀土学会2020学术年会暨江西(赣州)稀土资源绿色...

作者： yun-zhi tang Ning Song Xing-Xian Dong Yu-Hui Tan yun-zhi tang School of Metallurgy and Chemical Engineering Jiangxi University of Science and Technology

KSCN (0.292 g,3 mmol) and Nd(NO)·6HO (0.456 g,1 mmol) was added into 20 ml anhydrous ethanol.The mixture was thoroughly stirred,and then a clear solution was gained by filtering.Then,N,N,N-tributyl-1-butanaminiunitrate (0.912 g,3 mmol) was dissolved in 10 ml anhydrous ethanol and then mix it with the above solution.Reflux the reaction mixture at 334 K for 6 hours and then heat and volatilize the clear solution obtained by filtering to.After several days,block crystals were separated out at a temperature of 277 K.Thus we obtained a novel Rare-Earth Molecular Ferroelectrics (1) with High Curie temperature.The structure of 1 was determined by single-crystal X-ray diffraction (SCXRD) and further characterized by elemental analysis (EA),infrared spectra (IR),powder X-ray diffraction (PXRD),differential scanning calorimetry (DSC),second harmonic generation (SHG) and ferroelectric and piezoresponse force microscopy (PFM) measurements.SCXRD and structural analysis show that 1 crystallizes in a monoclinic space group Cc at 293 K.DSC and dielectric properties show that 1 undergoes a reversible structural phase transition with a Curie temperature of 377 K.

关键词： Rare-earth Reversible phase transition Molecular ferroelectrics Strong photoluminescence

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World Journal of Clinical Cases 2024年第10期12卷 1733-1741页

作者： Yi-Fei tang zhi-Hui Duan Department of Glaucoma and Cataracts Han Yang Eyegood Ophthalmic HospitalWuhan 430056Hubei ProvinceChina

BACKGROUND Diabetic patients with cataracts encounter specific difficulties during cataract surgery due to alterations in microcirculation,blood supply,metabolism,and the microenvironment.Traditional phacoemulsification may not fully tackle these issues,especially in instances with substantial preoperative astigmatism.The utilization of femtosecond laser-assisted phacoemulsification,in conjunction with Toric intraocular lens(IOL)implantation,offers a potentially more efficient strategy.This research seeks to evaluate the efficacy and possible complications of this approach in diabetic cataract patients.AIM To investigate the clinical efficacy and complications of femtosecond laser-assisted phacoemulsification combined with Toric IOL implantation in diabetic cataract patients,comparing it with traditional phacoemulsification methods.METHODS This retrospective study enrolled 120 patients with diabetes cataract from May 2019 to May 2021.The patients were divided into two groups:the control group underwent traditional phacoemulsification and Toric IOL implantation,while the treatment group received Len Sx femtosecond laser-assisted treatment.Outcome measures included naked eye vision,astigmatism,high-level ocular phase difference detection,clinical efficacy,and complication.RESULTS There were no significant preoperative differences in astigmatism or naked eyesight between the two groups.However,postoperative improvements were observed in both groups,with the treatment group showing greater enhancements in naked eye vision and astigmatism six months after the procedure.High-level corneal phase difference tests also indicated significant differences in favor of the treatment group.CONCLUSION This study suggests that femtosecond laser-assisted phacoemulsification combined with Toric IOL implantation appears to be more effective in enhancing postoperative vision in diabetic cataract patients compared to traditional methods offering valuable insights for clinical practice.

关键词： Diabetic cataract Femtosecond laser-assisted phacoemulsification Toric intraocular lens implantation Naked vision

Development of a scintillating-fiber-based beam monitor for the coherent muon-to-electron transition experiment

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Nuclear Science and Techniques 2024年第4期35卷 156-164页

作者： Yu Xu yun-Song Ning zhi-Zhen Qin Yao Teng Chang-Qing Feng Jian tang Yu Chen Yoshinori Fukao Satoshi Mihara Kou Oishi School of Physics Sun Yat-sen UniversityGuangzhou 510275China State Key Laboratory of Particle Detection and Electronics University of Science and Technology of ChinaHefei 230026China Department of Modern Physics University of Science and Technology of ChinaHefei 230026China High Energy Accelerator Research Organization(KEK) Ibaraki 305‑0801Japan Department of Physics Imperial College LondonLondon SW72AZUK

The coherent muon-to-electron transition(COMET)experiment is a leading experiment for the coherent conversion of μ^(-)N→e^(-)N using a high-intensity pulsed muon beamline,produced using innovative slow-extraction techniques.Therefore,it is critical to measure the muon beam characteristics.We set up a muon beam monitor(MBM),where scintillating fibers woven in a cross shape were coupled to silicon photomultipliers to measure the spatial profile and timing structure of the extracted muon beam for the COMET.The MBM detector was tested successfully with a proton beamline at the China Spallation Neutron Source and took data with good performance in the commissioning run.The development of the MBM,including its mechanical structure,electronic readout,and beam measurement results,are discussed.

关键词： Beam instrumentation Profile monitor Scintillating fiber Silicon photomultipliers

Grain-boundary segregation and grain growth in nanocrystalline substitutional solid solution alloys

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Journal of Materials Science & Technology 2024年第1期168卷 239-249页

作者： Fawei tang Chao Hou Hao Lu zhi Zhao Xiaoyan Song Faculty of Materials and Manufacturing Key Laboratory of Advanced Functional MaterialsMinistry of Education of ChinaBeijing University of TechnologyBeijing 100124China

A model for describing solute segregation at grain boundaries has been developed for substitutional solid solution alloys,which integrates multiple factors from atomic to microstructural scales.A concept of mo-lar Gibbs free energy of segregation was introduced to evaluate the segregating capability of the solute elements in a closed system,through which the influences of grain boundary structure,grain size,ma-terial composition,and external conditions were described.Based on the evaluation of various energy forms related to solute segregation and grain growth processes,the nature of the thermal stabilization of nanograin structures by solute segregation was disclosed.A criterion for the destabilization of nanostruc-tures,which is determined by the competition of the change rates between the molar Gibbs free energy of segregation and the total energy of grain boundaries with grain size,has been proposed.This study provided guideline to achieve high-temperature stability of nanograin structures of solid solution alloys even for the weakly segregating nanocrystalline systems.

关键词： Substitutional solid solution Grain boundary segregation Thermal stabilization Solute concentration Grain size

High Curie Temperature, Large Spontaneous Polarization and Direct Band Gap in a Perovskite-like Molecular Ferroelectrics

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High Curie Temperature, Large Spontaneous Polarization and D...

Antiviral treatment standards for hepatitis B:An urgent need for expansion

2018年中西部地区无机化学化工学术研讨会

作者： yun-zhi tang Chang-Feng Wang Chao Li School of Metallurgy and Chemical Engineering Jiangxi University of Science and Technology Ganzhou

Most of the molecular ferroelectrics suffer from the defects of low Curie temperature, small spontaneous and unitary performance, far away from the application in smart materials. [1-2] Here we reported a new perovskite-like molecular ferroelectrics [(γ-ammonium butyric acid)2 CdCl4]n, 1, which shows high curie temperature(355 K) and large spontaneous polarization(Ps = 7.2 u C/cm2). Especially, the further investigation shows that 1 is a direct-gap semiconductor with band gap(3.88 eV). X-ray single crystal diffractions measurement at 293 and 365 K reveals that the twist motions of γ-ammonium butyric acid and the relative "displacement" from positive ammonium and the negative [Cd(Ⅱ)Cl] triggered the para-ferroelectric phase transition. The exceptional dielectric response and heat anomalies as well as the X-ray diffraction powder diffraction dependence on temperatures further confirm its interesting reversible phase transition behaviour.

关键词： Molecular Ferroelectrics Spontaneous Polarization Direct Band Gap Pervoskite Structure

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World Journal of Gastroenterology 2024年第4期30卷 418-420页

作者： Zi-Hong Bao zhi-Kun Dai Hao-Xian tang Department of Infectious Diseases The First Affiliated Hospital of Shantou University Medical CollegeShantou 515041Guangdong ProvinceChina Medical College Shantou University Medical CollegeShantou 515041Guangdong ProvinceChina Department of Cardiology The First Affiliated Hospital of Shantou University Medical CollegeShantou 515041Guangdong ProvinceChina

The present letter to the editor is related to the review with the title“Past,present,and future of long-term treatment for hepatitis B virus.”Chronic hepatitis B(CHB)represents an important and pressing public health concern.Timely identification and effective antiviral therapy hold the potential to reduce liver-related mortality attributable to chronic infection with hepatitis B virus(HBV)substantially.However,the current global treatment rates for CHB remain conspicuously low,with the excessively stringent treatment criteria advocated by national CHB guidelines being a contributing factor to these low rates.Nevertheless,recent strides in comprehending this malady and the emergence of novel antiviral agents prompt the imperative re-evaluation of treatment standards to extend the sphere of potential beneficiaries.An impending need arises for a novel paradigm for the classification of patients with CHB,the expansion of antiviral treatment eligibility for HBV-infected individuals,and even the streamlining of the diagnostic process for CHB to amplify cost-effectiveness and augment survival prospects.

关键词： Hepatitis B virus Chronic hepatitis B Antiviral treatment criteria Serum alanine aminotransferase Liver-related mortality Letter to the Editor

Gut-targeted therapies for type 2 diabetes mellitus: A review

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World Journal of Clinical Cases 2024年第1期12卷 1-8页

作者： Tian-Cheng Xu yun Liu zhi Yu Bin Xu Key Laboratory of Acupuncture and Medicine Research of Ministry of Education Nanjing University of Chinese MedicineNanjing 210023Jiangsu ProvinceChina

Type 2 diabetes mellitus(T2DM)is a chronic metabolic disorder characterized by hyperglycemia and insulin resistance.The global prevalence of T2DM has reached epidemic proportions,affecting approximately 463 million adults worldwide in 2019.Current treatments for T2DM include lifestyle modifications,oral antidiabetic agents,and insulin therapy.However,these therapies may carry side effects and fail to achieve optimal glycemic control in some patients.Therefore,there is a growing interest in the role of gut microbiota and more gut-targeted therapies in the management of T2DM.The gut microbiota,which refers to the community of microorganisms that inhabit the human gut,has been shown to play a crucial role in the regulation of glucose metabolism and insulin sensitivity.Alterations in gut microbiota composition and diversity have been observed in T2DM patients,with a reduction in beneficial bacteria and an increase in pathogenic bacteria.This dysbiosis may contribute to the pathogenesis of the disease by promoting inflammation and impairing gut barrier function.Several gut-targeted therapies have been developed to modulate the gut microbiota and improve glycemic control in T2DM.One potential approach is the use of probio-tics,which are live microorganisms that confer health benefits to the host when administered in adequate amounts.Several randomized controlled trials have demonstrated that certain probiotics,such as Lactobacillus and Bifidobacterium species,can improve glycemic control and insulin sensitivity in T2DM patients.Mechanisms may include the production of short-chain fatty acids,the improvement of gut barrier function,and the reduction of inflammation.Another gut-targeted therapy is fecal microbiota transplantation(FMT),which involves the transfer of fecal material from a healthy donor to a recipient.FMT has been used successfully in the treatment of Clostridioides difficile infection and is now being investigated as a potential therapy for T2DM.A recent randomized controlled trial showed that FMT from lea

关键词： Type 2 diabetes mellitus Gastroenterology Bacteria Implanted device

Biopsy forceps are useful for measuring esophageal varices in vitro

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World Journal of Gastrointestinal Surgery 2024年第2期16卷 539-545页

作者： zhi-Hui Duan Sheng-yun Zhou Endoscopy Center Xingtai People’s HospitalXingtai 054000Hebei ProvinceChina

BACKGROUND To avoid acute variceal bleeding in cirrhosis,current guidelines recommend screening for high-risk esophageal varices(EVs)by determining variceal size and identifying red wale markings.However,visual measurements of EV during routine endoscopy are often inaccurate.AIM To determine whether biopsy forceps(BF)could be used as a reference to improve the accuracy of binary classification of variceal size.METHODS An in vitro self-made EV model with sizes ranging from 2 to 12 mm in diameter was constructed.An online image-based survey comprising 11 endoscopic images of simulated EV without BF and 11 endoscopic images of EV with BF was assembled and sent to 84 endoscopists.The endoscopists were blinded to the actual EV size and evaluated the 22 images in random order.RESULTS The respondents included 48 academic and four private endoscopists.The accuracy of EV size estimation was low in both the visual(13.81%)and BF-based(20.28%)groups.The use of open forceps improved the ability of the endoscopists to correctly classify the varices by size(small≤5 mm,large>5 mm)from 71.85%to 82.17%(P<0.001).CONCLUSION BF may improve the accuracy of EV size assessment,and its use in clinical practice should be investigated.

关键词： Accuracy Liver cirrhosis Esophageal varices Endoscopy Measurement