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Excellent energy storage performance in Bi_(0.5)Na_(0.5)TiO_(3)-based lead-free high-entropy relaxor ferroelectrics via B-site modification

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Journal of Advanced Ceramics 2024年第3期13卷 345-353页

作者： Kaihua Yang Gengguang Luo Li Ma Ruoxuan Che Zhiyi Che qin feng Zhenyong Cen Xiyong Chen Jiajun Zhou Nengneng Luo State Key Laboratory of Featured Metal Materials and Life-cycle Safety for Composite Structures School of ResourcesEnvironment and MaterialsGuangxi UniversityNanning 530004China School of Optical and Electronic Information Key Lab of Functional Materials for Electronic Information(B)of Ministry of EducationHuazhong University of Science and TechnologyWuhan 430074China

Next-generation advanced high/pulsed power capacitors urgently require dielectric materials with outstanding energy storage performance.Bi_(0.5)Na_(0.5)TiO_(3)-based lead-free materials exhibit high polarization,but the high remanent polarization and large polarization hysteresis limit their applications in dielectric capacitors.Herein,high-entropy perovskite relaxor ferroelectrics(Na_(0.2)Bi_(0.2)Ba_(0.2)Sr_(0.2)Ca_(0.2))(Ti1-x%Zrx%)O_(3)are designed by adding multiple ions in the A-site and replacing the B-site Ti^(4+)with a certain amount of Zr^(4+).The newly designed system showed high relaxor feature and slim polarization-electric(P-E)loops.Especially,improved relaxor feature and obviously delayed polarization saturation were found with the increasing of Zr^(4+).Of particular importance is that both high recoverable energy storage density of 6.6 J/cm^(3) and energy efficiency of 93.5%were achieved under 550 kV/cm for the ceramics of x=6,accompanying with excellent frequency stability,appreciable thermal stability,and prosperous discharge property.This work not only provides potential dielectric materials for energy storage applications,but also offers an effective strategy to obtain dielectric ceramics with ultrahigh comprehensive energy storage performance to meet the demanding requirements of advanced energy storage applications.

关键词： energy storage density (Bi_(0.5)Na_(0.5))TiO_(3) high-entropy perovskite ceramics polarization saturation relaxor ferroelectrics(RFEs)

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Aluminum and Activated Alumina Powder Additions on Microwave Synthesis of Al_(4)SiC_(4)

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China's Refractories 2024年第1期33卷 44-48页

作者： WANG Li LIU Shijie WEI Haoyu MA Juanjuan DONG Binbin GENG Shangrui YAN Miaoxin qin feng GUO Yusen Henan Key Laboratory of Green Building Materials Manufacturing and Intelligent Equipemnt Luoyang Institute of Science and TechnologyLuoyang 471023China

Aiming at improving the properties of magnesia carbon materials,silicon aluminum carbide(Al_(4)SiC_(4))containing materials were prepared using industrial aluminum powder,silicon carbide powder,and graphite as raw materials,and activated alumina powder as an additive,mixing thoroughly,pressing into cylinders and then firing at 1200℃for 30 min in a carbon embedded atmosphere by the microwave method.The effects of the aluminum powder addition(20%and 24%,by mass)and activated alumina powder addition(0,3%,5%and 7%,by mass)on the microwave synthesis of Al_(4)SiC_(4) as well as the effect of the obtained Al_(4)SiC_(4) containing material on the properties of magnesia carbon bricks were studied.The results show that:compared with the samples with 20%aluminum powder,those with 24%aluminum powder generate more Al_(4)SiC_(4).With the activated alumina powder addition increasing from 0 to 7%,the amount of Al_(4)SiC_(4) generated increases first and then decreases.Compared with the sample without activated alumina powder,the samples with activated alumina powder show lower bulk density and higher apparent porosity.With the activated alumina powder addition increasing from 3%to 7%,the bulk density of the samples increases first and then decreases,while the apparent porosity of the samples shows an opposite trend.The optimal additions are 24%aluminum powder and 5%activated alumina powder,and Al_(4)SiC_(4) synthesized in this sample has a hexagonal plate structure.With the synthesized Al_(4)SiC_(4) containing material added,the magnesia carbon brick has slightly increased cold modulus of rupture,basically the same modulus of elasticity and improved oxidation resistance.

关键词： aluminum powder activated alumina powder microwave synthesis Al_(4)SiC_(4) magnesia carbon bricks

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Microwave-assisted Synthesis of Al_(4)SiC_(4) and Its Effect on Properties of MgO-C Refractories

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China's Refractories 2024年第1期33卷 14-17页

作者： WANG Li LIU Shijie WEI Haoyu GUO Yanyan GENG Shangrui YAN Miaoxin qin feng GUO Yusen Ma Juanjuan DONG Binbin Henan Key Laboratory of Green Building Materials Manufacturing and Intelligent Equipemnt Luoyang Institute of Science and TechnologyLuoyang 471023China

Al_(4)SiC_(4) was synthesized from Al powder, silicon carbide, and graphite by microwave sintering, and characterized by XRD and SEM. Then the synthesized material was added to the magnesia carbon refractory brick to study its effect on the oxidation resistance, apparent porosity, bulk density, elastic modulus, and modulus of rupture. It is found that Al_(4)SiC_(4) can be synthesized by microwave sintering at 1 300 ℃ and the addition of Al_(4)SiC_(4)-containing material as an antioxidant can enhance the oxidation resistance of the magnesia carbon refractory brick.

关键词： microwave-assisted synthesis Al_(4)SiC_(4) MgO-C refractories oxidation resistance

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The infection kinetics and transmission potential of two Guaico Culex viruses in Culex quinquefasciatus mosquitoes

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Virologica Sinica 2024年第2期39卷 228-234页

作者： Ru-Yi Chen Teng Zhao Jing-Jing Guo feng Zhu Na-Na Zhang Xiao-feng Li Hai-Tao Liu Fei Wang Yong-Qiang Deng Cheng-feng qin College of Bioscience and Bioengineering Jiangxi Agricultural UniversityNanchang330045China State Key Laboratory of Pathogen and Biosecurity Beijing Institute of Microbiology and EpidemiologyAMMSBeijing100071China School of Life Sciences Southwest Forestry UniversityKunming650224China

Guaico Culex virus(GCXV)is a newly identified segmented Jingmenvirus from Culex spp.mosquitoes in Central and South America.The genome of GCXV is composed of four or five single-stranded positive RNA segments.However,the infection kinetics and transmission capability of GCXV in mosquitoes remain unknown.In this study,we used reverse genetics to rescue two GCXVs(4S and 5S)that contained four and five RNA segments,respectively,in C6/36 cells.Further in vitro characterization revealed that the two GCXVs exhibited comparable replication kinetics,protein expression and viral titers.Importantly,GCXV RNAs were detected in the bodies,salivary glands,midguts and ovaries of Culex quinquefasciatus at 4–10 days after oral infection.In addition,two GCXVs can colonize Cx.quinquefasciatus eggs,resulting in positive rates of 15%–35%for the second gonotrophic cycle.In conclusion,our results demonstrated that GCXVs with four or five RNA segments can be detected in Cx.quinquefasciatus eggs during the first and second gonotrophic cycles after oral infection.

关键词： Guaico Culex virus(GCXV) Jingmenvirus Culex quinquefasciatus Vertical transmission

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Unravelling the anisotropic light-matter interaction in strainengineered trihalide MoCl_(3)

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Nano Research 2024年第4期17卷 2981-2987页

作者： Yuxuan Sun Ziang Liu Zeya Li feng qin Junwei Huang Caiyu Qiu Hongtao Yuan National Laboratory of Solid State Microstructures Jiangsu Key Laboratory of Artificial Functional MaterialsCollege of Engineering and Applied Sciencesand Collaborative Innovation Center of Advanced MicrostructuresNanjing UniversityNanjing 210000China

Layered trihalides exhibit distinctive band structures and physical properties due to the sixfold coordinated 3d or 4d transition metal site and partially occupied d orbitals,holding great potential in condensed matter physics and advanced electronic applications.Prior research focused on trihalides with highly symmetric honeycomb-like structures,such as CrI3 andα-RuCl_(3),while the role of crystal anisotropy in trihalides remains elusive.In particular,the trihalide MoCl_(3) manifests strong in-plane crystal anisotropy with the largest difference in Mo–Mo interatomic distances.Research on such material is imperative to address the lack of investigations on the effect of anisotropy on the properties of trihalides.Herein,we demonstrated the anisotropy of MoCl_(3) through polarized Raman spectroscopy and further tuned the phonon frequency via strain engineering.We showed the Raman intensity exhibits twofold symmetry under parallel configuration and fourfold symmetry under perpendicular configuration with changing the polarization angle of incident light.Furthermore,we found that the phonon frequencies of MoCl_(3) decrease gradually and linearly with applying uniaxial tensile strain along the axis of symmetry in the MoCl_(3) crystal,while those frequencies increase with uniaxial tensile strain applied perpendicularly.Our results shed light on the manipulation of anisotropic light-matter interactions via strain engineering,and lay a foundation for further exploration of the anisotropy of trihalides and the modulation of their electronic,optical,and magnetic properties.

关键词： layered trihalide MoCl_(3) polarized Raman spectroscopy strain engineering anisotropy

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A Clinical Observation Report on Prenatal Management and Postnatal Treatment of Congenital Granular Cell Epulis

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Maternal-Fetal Medicine 2024年第2期6卷 102-105页

作者： feng qin Xiaochuan Xu Yong Yang Qiong Li Ting Huang Xiaoyan Chen Xiaolan Chen Yamin Liu Gongli Chen Department of Gynecology and Obstetrics Chongqing Health Center for Women and ChildrenWomen and Children's Hospital of Chongqing Medical UniversityChongqing 401147China Department of Pathology Chongqing Health Center for Women and ChildrenWomen and Children's Hospital of Chongqing Medical UniversityChongqing 401147China

Introduction Congenital granular cell epulis(CGCE)is a rare,benign tumor that manifests on the mucosal surface of the alveolar ridge in newborns.It was initially described by Neumann in 1871 and has been referred to by various names such as congenital epulis,congenital epulis of the newborn,and congenital granular cell tumor.1 Documentation on larger tumors is limited and reported diameters vary.2 Diagnosis necessitates histological examination and immunohistochemical staining,typically revealing negative immunoreactivity for S-100 and cluster of differentiation 68(CD68).3,4 This article presents a case of CGCE with weakly positive S-100 and CD68 staining,alongside a relatively large size.Additionally,it conducts a literature review on diverse aspects,encompassing multidisciplinary prenatal diagnosis,antenatal management,choice of delivery mode during childbirth,and postnatal treatment,with the objective of augmenting clinicians’comprehension of the ailment.The study adhered to the guidelines of the Declaration of Helsinki and obtained informed consent from the patient and approval from the medical ethics committee of Chongqing Health Center for Women and Children.

关键词： Congenital epulis Fetal Immunohistochemical Prenatal management Postnatal treatment

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Heterogeneous population distribution enhances resistance to wheat lodging by optimizing the light environment

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Journal of Integrative Agriculture 2024年第7期23卷 2211-2226页

作者： Yibo Hu feng qin Zhen Wu Xiaoqin Wang Xiaolong Ren Zhikuan Jia Zhenlin Wang Xiaoguang Chen Tie Cai College of Agronomy Northwest A&F UniversityYangling 712100China Key Laboratory of Crop Physi-Ecology and Tillage Science in Northwestern Loess Plateau Ministry of Agriculture and Rural AffairsNorthwest A&F UniversityYangling 712100China College of Agronomy Shandong Agricultural University/State Key Laboratory of Crop BiologyTai’an 271018China Xuzhou Institute of Agricultural Sciences in Jiangsu Xuhuai Area Xuzhou 221131China

Lodging is still the key factor that limits continuous increases in wheat yields today,because the mechanical strength of culms is reduced due to low-light stress in populations under high-yield cultivation.The mechanical properties of the culm are mainly determined by lignin,which is affected by the light environment.However,little is known about whether the light environment can be sufficiently improved by changing the population distribution to inhibit culm lodging.Therefore,in this study,we used the wheat cultivar“Xinong 979”to establish a low-density homogeneous distribution treatment(LD),high-density homogeneous distribution treatment(HD),and high-density heterogeneous distribution treatment(HD-h)to study the regulatory effects and mechanism responsible for differences in the lodging resistance of wheat culms under different population distributions.Compared with LD,HD significantly reduced the light transmittance in the middle and basal layers of the canopy,the net photosynthetic rate in the middle and lower leaves of plants,the accumulation of lignin in the culm,and the breaking resistance of the culm,and thus the lodging index values increased significantly,with lodging rates of 67.5%in 2020–2021 and 59.3%in 2021–2022.Under HD-h,the light transmittance and other indicators in the middle and basal canopy layers were significantly higher than those under HD,and the lodging index decreased to the point that no lodging occurred.Compared with LD,the activities of phenylalanine ammonia-Lyase(PAL),4-coumarate:coenzyme A ligase(4CL),catecholO-methyltransferase(COMT),and cinnamyl-alcohol dehydrogenase(CAD)in the lignin synthesis pathway were significantly reduced in the culms under HD during the critical period for culm formation,and the relative expression levels of TaPAL,Ta4CL,TaCOMT,and TaCAD were significantly downregulated.However,the activities of lignin synthesis-related enzymes and their gene expression levels were significantly increased under HD-h compared with HD.A partial least squares path modeling

关键词： canopy light environment lignin lodging population distribution wheat

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Rapid development of double-hit mRNA antibody cocktail against orthopoxviruses

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Signal Transduction and Targeted Therapy 2024年第4期9卷 1768-1776页

作者： Hang Chi Suo-Qun Zhao Ru-Yi Chen Xing-Xing Suo Rong-Rong Zhang Wen-Hui Yang Dong-Sheng Zhou Min Fang Bo Ying Yong-Qiang Deng Cheng-feng qin State Key Laboratory of Pathogen and Biosecurity Beijing Institute of Microbiology and EpidemiologyAMMS100071BeijingChina College of Life Sciences Inner Mongolia Agricultural UniversityHohhot010018Inner MongoliaChina School of Life Sciences Henan UniversityKaifeng475004HenanChina Suzhou Abogen Biosciences Co. LtdSuzhou215123JiangsuChina Research Unit of Discovery and Tracing of Natural Focus Diseases Chinese Academy of Medical Sciences100071BeijingChina

The Orthopoxvirus genus,especially variola virus(VARV),monkeypox virus(MPXV),remains a significant public health threat worldwide.The development of therapeutic antibodies against orthopoxviruses is largely hampered by the high cost of antibody engineering and manufacturing processes.mRNA-encoded antibodies have emerged as a powerful and universal platform for rapid antibody production.Herein,by using the established lipid nanoparticle(LNP)-encapsulated mRNA platform,we constructed four mRNA combinations that encode monoclonal antibodies with broad neutralization activities against orthopoxviruses.In vivo characterization demonstrated that a single intravenous injection of each LNP-encapsulated mRNA antibody in mice resulted in the rapid production of neutralizing antibodies.More importantly,mRNA antibody treatments showed significant protection from weight loss and mortality in the vaccinia virus(VACV)lethal challenge mouse model,and a unique mRNA antibody cocktail,Mix2a,exhibited superior in vivo protection by targeting both intracellular mature virus(IMV)-form and extracellular enveloped virus(EEV)-form viruses.In summary,our results demonstrate the proof-of-concept production of orthopoxvirus antibodies via the LNP-mRNA platform,highlighting the great potential of tailored mRNA antibody combinations as a universal strategy to combat orthopoxvirus as well as otheremerging viruses.

关键词： proof universal neutral

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A Model to Evaluate the Device-Level Performance of Thermoelectric Cooler with Thomson Effect Considered

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Journal of Thermal Science 2022年第3期31卷 712-726页

作者： GONG Tingrui GAO Lei WU Yongjia TAN Haoshu qin feng XIN Xiong SHEN Limei LI Juntao MING Tingzhen Microsystem&Terahertz Research Center China Academy of Engineering PhysicsChengdu610200China Institute of Electronic Engineering China Academy of Engineering PhysicsMianyang621999China School of Civil Engineering and Architecture Wuhan University of TechnologyWuhan430070China Department of Refrigeration&Cryogenics Engineering Huazhong University of Science and TechnologyWuhan430074Chin

In this paper,a one-dimensional thermodynamic model was developed to evaluate the device-level performance of thermoelectric cooler(TEC)with the Thomson effect,contact resistance,gap heat leakage,heat sink,and heat load taken into account.The model was generalized and simplified by introducing dimensionless parameters.Experimental measurements showed good agreement with analytical results.The parametric analysis indicated that the influence of the Thomson effect on cooling capacity continued to expand with increasing current,while the effect on COP hardly changed with current.Low thermal contact resistance was beneficial to obtain lower hot-junction temperature,which can even reduce 2 K compared with the electrical contact resistance in the case study.The gap heat leakage was a negative factor affecting the cooling performance.When the thermal resistance of the heat sink was small,the negative effect of heat leakage on performance would be further enlarged.The enhancement of heat load temperature would increase the cooling power of the TEC.For example,an increase of 5 K in heat load can increase the cooling capacity by about 4%.However,once the current exceeded the optimum value,the raising effect on the cooling power would be weakened.The research can provide an analytical approach for the designer to perform trade studies to optimize the TEC system.

关键词： thermoelectric cooler thermodynamic model Thomson effect contact resistance device-level performance

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机器学习算法在青藏高原孢粉-气候定量重建中的尝试

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第四纪研究 2024年第3期44卷 704-714页

作者：秦锋赵艳中国科学院地理科学与资源研究所陆地表层格局与模拟院重点实验室北京100101 中国科学院大学北京100049

孢粉是定量重建过去气候变化的重要代用指标,在中国已开展了大量基于孢粉数据的气候定量重建研究。然而,只有少数研究采用机器学习算法来建立孢粉-气候重建模型,不同机器学习算法的可靠性尚需验证。本研究采用3种机器学习算法(包括随机... 详细信息

孢粉是定量重建过去气候变化的重要代用指标,在中国已开展了大量基于孢粉数据的气候定量重建研究。然而,只有少数研究采用机器学习算法来建立孢粉-气候重建模型,不同机器学习算法的可靠性尚需验证。本研究采用3种机器学习算法(包括随机森林、增强回归树和人工神经网络算法),基于青藏高原及其周边地区现代孢粉百分比数据,及由其计算而来的植物功能型得分数据,建立气候定量重建模型;同时用两种常规方法(现代类比法和加权平均偏最小二乘法)建立的模型作为对比,检验机器学习算法基于孢粉数据开展气候定量重建的可靠性。结果显示5种方法基于孢粉百分比和植物功能型得分数据建立的最暖月平均降水量和最冷月平均温度重建模型,从均方根误差(RMSE)和决定系数(R2)两个评价指标来看,都有较高可靠性。3种机器学习算法中,随机森林和增强回归树的可靠性比人工神经网络算法高,二者建立的模型性能非常接近,尤其在建立植物功能型-最冷月平均温度重建模型时,二者表现是所有方法中最好的;常规方法中,加权平均偏最小二乘法在大多数情况下表现明显不及3种机器学习算法,而现代类比法的可靠性稍优于3种机器学习算法,但考虑该方法对空间自相关较为敏感,其表现有高估的风险。本研究所用的机器学习算法极有潜力用于青藏高原地区的古气候定量重建,尤其是随机森林和增强回归树算法。针对特定地区特定气候因子,不同方法基于孢粉数据建立气候重建模型的适用性可能不同,开展具体工作时有必要对比多种方法,选取其中可靠性最高的方法建立孢粉-气候模型。

关键词：孢粉气候定量重建机器学习算法青藏高原

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