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Effect of SrO Content on Structure,Thermal Properties and Chemical Stability of Bi2O3-B2O3-ZnO-SrO Low-melting Glass for Si-Al Alloy Package

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Journal of Wuhan University of Technology(Materials Science) 2020年第2期35卷 368-376页

作者： WU Zhilun ZHANG Ming ZHANG Chunyan MENG Fancheng lin huixing College of Materials Science and Engineering Chongqing University of TechnologyChongqing 400054China Key Laboratory of Inorganic Functional Materials and Devices Shanghai Institute of CeramicsChinese Academy of SciencesShanghai 201800China

The 40Bi2O3-30B2O3-(30-x)ZnO-xSrO (x=0-15mol%,BBZSr) glass system was prepared by the conventional melt quenching *** effect of SrO addition on structure,thermal properties,chemical stability and sealing performance of BBZSr glass were investigated *** experimental results show that the total proportions of [BO3] group and [BO4] group decrease and the vibrations of [BiO3] group and [BiO6] group become weaker with the increase of SrO addition content,suggesting the glass network structure is strengthened owing to the SrO ***,both the thermal and chemical stability were significantly improved as the SrO content was *** the SrO content increased from 0 to 15mol%,the glass transition temperature and softening temperature slightly increased from 380 to 388 ℃ and from 392.7 to 402.2 ℃,respectively,meanwhile the coefficient of thermal expansion also increased from 10.49×10^-6 to 11.16×10^-6/℃ (30-300 ℃).The BBZSr glass with 15mol% SrO exhibited excellent comprehensive properties with low glass transition temperature(384.9 ℃),low softening temperature(400.3 ℃),high coefficient of thermal expansion (11.14×10^-6 ℃,30-300 ℃),good thermal and chemical ***,the glass had the good wetting behavior and sealing performance for Al-50%Si alloy.

关键词： low-melting sealing lead-free glass Bi2O3-B2O3-ZnO-SrO glass silicon-aluminium alloy thermal expansion

SrGa_(12)O_(19):The first low-ε_(r) Ga-based microwave dielectric ceramic with anomalous positiveτ_(f)

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Journal of Advanced Ceramics 2024年第9期13卷 1432-1441页

作者： Yang Yang Weishuang Fang huixing lin Jie Li Huaicheng Xiang Ying Tang Lei Li Liang Fang Guangxi Universities Key Laboratory of Non-ferrous Metal Oxide Electronic Functional Materials and Devices and Guangxi Key Laboratory of Optical and Electronic Materials and DevicesCollege of Materials Science and EngineeringGuilin University of TechnologyGuilin 541004China Key Laboratory of Inorganic Functional Material and Devices Shanghai Institute of CeramicsChinese Academy of SciencesShanghai 200050China Laboratory of Dielectric Materials School of Materials Science and EngineeringZhejiang UniversityHangzhou 310058China

Dielectric ceramics with low permittivity(ε_(r)),high quality factor(Q×f),and near-zero resonant frequency(τ_(f))in the microwave bands are key materials used in fifth/sixth-generation(5G/6G)telecommunication,whileτ_(f) of most low-εr microwave dielectric ceramics is relatively *** this work,the first low-εr Ga-based ceramic SrGa_(12_O_(19) with an anomalous positiveτ_(f) was reported,and the causes of the positiveτ_(f),intrinsic polarization,and loss mechanism were systematically studied.X-ray diffraction(XRD)and transmission electron microscopy(TEM)revealed that the SrGa_(12_O_(19) ceramic formed a pure hexagonal magnetoplumbite structure with spinel blocks and rock-salt blocks stacked along the crystallographic *** sintered at 1430℃,it possessed the optimal microwave dielectric properties of a lowεr of 14.46,high Q×f of 64,705 GHz,and exceptional positiveτ_(f) of+55.7 ppm/℃,along with a low linear thermal expansion coefficient(αL)of 11.617 ppm/℃.The large positive deviation betweenεr andεr(C–M)of 45.31%resulted from the rattling effect of atoms in the rock-salt *** unique positiveτ_(f)(+55.7 ppm/℃)was governed by the rattling effect,resulting in a positiveταm(the temperature coefficient of ion polarizability)of 8.489 ppm/℃ and a large negative temperature coefficient of permittivity(τε)of−132.864 ppm/℃.Phillips–Vechten–Levine(P–V–L)chemical bond theory revealed greater contributions of the spinel block to bond ionicity(fi,52.95%),permittivity(ε,55.15%),bond energy(E,56.87%),and lattice energy(U,74.88%)than those of the rock-salt *** intrinsic dielectric properties were analyzed using infrared(IR)reflectivity *** favorable performance of the SrGa_(12_O_(19) ceramic indicated that it is a novelτ_(f) *** selection of compounds with different structural layer combinations provides a new idea for exploring excellent microwave dielectric ceramics.

关键词： magnetoplumbite microwave dielectric properties rattling effect chemical bond theory

Isolation and characterization of a porcine epidemic diarrhea virus strain YC2014 with high pathogenicity in China

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Isolation and characterization of a porcine epidemic diarrhe...

新型鹅细小病毒徐州分离株(NGPV XZ-01株)对半番鸭生长发育的影响

中国畜牧兽医学会兽医公共卫生学分会第五次学术研讨会

作者： huixing lin Hongjie Fan College of Veterinary Medicine Nanjing Agricultural University

Porcine epidemic diarrhea virus(PEDV) is the main causative agent of porcine epidemic diarrhea(PED),a devastating enteric disease that is characterized by watery diarrhea,vomiting,dehydration and significant mortality in *** 80 to 100 percent of PEDV-infected piglets die within 24 h of being infected with virulent PEDV strains,resulting in tremendous economic losses to the swine *** December 2010,a large-scale outbreak of diarrhea,characterized by watery stool,dehydration,and vomiting,with80 to 100% morbidity and 50 to 90% mortality in suckling piglets,has been observed in swine farms in *** evidence indicates that this large-scale outbreak of diarrhea may be caused by highly virulent *** YC2014 porcine epidemic diarrhea virus(PEDV) strain was isolated from intestinal samples of suckling piglets with acute diarrhea in *** cytopathic effects were observed on Vero cells following infection with the YC2014 PEDV *** analysis of the S gene nucleotide demonstrated that the YC2014 PEDV strain was clustered with the PEDV epidemic strains,especially those isolated in Southeast China since 2012,with >99% nucleotide identity to these PEDV *** S gene sequence of YC2014 shared only94.0%4.4% identities with classical CV777,DR13 and JS2008 strains,with 18 nucleotide insertion in four separate sites and 6 nucleotide deletion in one *** the virus pathogenicity analysis of YC2014,traditional inactivated PEDV vaccines made from CV777 or DR13 could not protect piglets from YC2014 challenge,while inactivated YC2014 could provided piglets with 100% protection against YC2014 *** results showed that,great antigenicity variation had occurred to this YC2014 PEDV *** YC2014 PEDV strain is critical for future pathogenic and antigenic studies,as well as for the development of effective preventive and control vaccines against PEDV.

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黑龙江畜牧兽医 2024年第12期 64-68,126-128页

作者：迟兰蔺辉星徐州生物工程职业技术学院江苏徐州221006 南京农业大学动物医学院南京210095

为了探究新型鹅细小病毒徐州分离株(NGPV XZ-01株)对半番鸭生长发育的影响,试验将180只健康非免疫半番鸭随机分为3组,分别为对照组、3日龄攻毒组和7日龄攻毒组,每组60只,对照组于3日龄时皮下注射灭菌生理盐水0.2 mL,3日龄攻毒组和7日龄... 详细信息

为了探究新型鹅细小病毒徐州分离株(NGPV XZ-01株)对半番鸭生长发育的影响,试验将180只健康非免疫半番鸭随机分为3组,分别为对照组、3日龄攻毒组和7日龄攻毒组,每组60只,对照组于3日龄时皮下注射灭菌生理盐水0.2 mL,3日龄攻毒组和7日龄攻毒组分别于3日龄和7日龄时皮下注射NGPV XZ-01株病毒液(第7代,效价为5.7 lgELD_(50)/mL)0.2 mL,攻毒后观察并记录各组的生长发育情况、临床症状、发病和死亡情况,并对喙长和体重进行测定,于25日龄时全部扑杀,进行剖检、病理切片观察和X光检查。结果表明:攻毒后,3日龄攻毒组和7日龄攻毒组均生长发育迟缓或成僵鸭;24日龄时,3日龄攻毒组和7日龄攻毒组的体型明显小于对照组,3日龄攻毒组体型明显小于7日龄攻毒组。试验期间,3日龄攻毒组和7日龄攻毒组表现为精神萎靡不振、喜卧、打堆、排白色或黄白色粪便,部分患鸭出现运动障碍、瘫痪等症状;随着日龄的增长,上下喙变短及舌头外露的症状逐渐明显。其中3日龄攻毒组发病率为90.0%、死亡率为11.7%;7日龄攻毒组发病率为76.7%、死亡率为6.7%;对照组无发病和死亡情况。10~22日龄时,3日龄攻毒组和7日龄攻毒组的体重和喙长均显著低于对照组(P<0.05),3日龄攻毒组的体重和喙长均显著低于7日龄攻毒组(P<0.05)。3日龄攻毒组和7日龄攻毒组剖检可见泄殖腔膨大,肠道内容物稀薄,肝脏均出现水肿、质脆等病变;病理切片观察可见十二指肠肠绒毛顶端上皮细胞坏死,十二指肠绒毛不同程度脱落,部分肠腺坏死;部分肝细胞出现坏死,肝窦淤血,有炎性细胞浸润;其他脏器未见明显病变。对照组未见明显异常。X光检查可见3日龄攻毒组和7日龄攻毒组下喙、翅、腿等部位明显小于对照组,且胫骨长度远低于对照组。说明NGPV XZ-01株可使半番鸭的生长发育明显受阻,具有很强的致病性,且对半番鸭的影响随感染日龄的增加而减小。

关键词：鸭短喙侏儒综合征新型鹅细小病毒徐州分离株半番鸭生长发育

新型鹅细小病毒徐州分离株NGPV XZ-01的分离和致病性研究

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畜牧与兽医 2024年第2期56卷 82-88页

作者：迟兰蔺辉星徐州生物工程职业技术学院江苏徐州221006 南京农业大学江苏南京210095

为了研究2021年6月江苏徐州某商品半番鸭养殖场所发疾病的病原及其致病性,从该养殖场发病的半番鸭群中无菌采集肝脏、脾脏、肠道等临床样品,采用PCR方法对病原进行鉴定,将所采集样本处理后接种至非免疫鸭胚中,连续多次传代后,对鸭胚组... 详细信息

为了研究2021年6月江苏徐州某商品半番鸭养殖场所发疾病的病原及其致病性,从该养殖场发病的半番鸭群中无菌采集肝脏、脾脏、肠道等临床样品,采用PCR方法对病原进行鉴定,将所采集样本处理后接种至非免疫鸭胚中,连续多次传代后,对鸭胚组织及尿囊液进行病理学、电镜检查及动物试验。结果显示:PCR检测结果鉴定为新型鹅细小病毒阳性;鸭胚尿囊液在电镜下观察到细小病毒粒子,胚体病理切片观察显示符合细小病毒所致病变;动物试验显示,攻毒试验鸭主要表现为生长发育明显受阻,大部分试验鸭成为“僵鸭”,于20日龄后陆续出现上下喙变短、舌头外露等症状,剖检病变主要为肠内容物稀薄及泄殖腔膨大,肠道组织切片观察显示肠绒毛上皮细胞坏死、脱落及部分肠腺坏死,符合鸭短喙侏儒综合征(short beak and dwarfism syndrome,SBDS)所致雏鸭的症状与病变。结果表明:该肉鸭养殖场所发疾病为SBDS,将该场分离的病毒命名为新型鹅细小病毒徐州分离株(NGPV XZ-01株)。

关键词：鸭短喙侏儒综合征新型鹅细小病毒徐州分离株分离鉴定动物试验

Study on properties of ultra-low dielectric loss mPPO/MTCLT composites prepared by injection molding

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Journal of Advanced Dielectrics 2022年第3期12卷 28-34页

作者： Yahan Liu Haiyi Peng Xiaogang Yao Minmin Mao Kaixin Song huixing lin College of Electronic Information and Engineering Hangzhou Dianzi University 1158 Baiyang Street 2nd StreetHangzhou 310018P.R.China Key Laboratory of Inorganic Functional Materials and Devices Shanghai Institute of Ceramics Chinese Academy of Sciences588 Heshuo RoadShanghai 201800P.R.China

A novel category of polyphenylene oxide/high-impact polystyrene(PPO/HIPS)alloy was used as the polymer matrix(abbreviated as mPPO)and loaded with different volume fractions(0,10,20,30,40,50 vol.%)of MgTiO_(3)-Ca_(0.7)La_(0.2)TiO_(3)(abbreviated as MTCLT)ceramics to prepare composites by injection *** micromorphology,density,dielectric,thermal and mechanical properties were analyzed in *** experimental results show that the composites possess a compact microstructure because HIPS increases the fluidity of *** to the excellent dielectric properties of both mPPO and MTCLT,the composites have an extremely low dielectric *** realization of the high ceramic filler fraction greatly limits the thermal expansion of the polymer chain by introducing the interphase,so that the coefficient of thermal expansion of the composite material could be as low as 21.8 ppm/°*** the same time,the presence of ceramic particles could reinforce the mechanical property of the *** the ceramic filler fraction is higher than 20 vol.%,the bending strength of the composite material is around 110 *** the ceramic filler fraction is 40 vol.%,the composite possesses the best comprehensive *** dielectric constant is 6.81,the dielectric loss is 0.00104,the thermal expansion coefficient is as low as 25.3 ppm/°C,and the bending strength is 110.4 *** to its excellent properties,this material can be a good candidate in the field of microwave communication.

关键词： Injection molding composites dielectric properties polyphenylene oxide alloy

二维编织陶瓷基复合材料偏轴拉伸力学性能预测

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复合材料学报 2018年第12期35卷 3423-3432页

作者：王奇志林慧星许赟泉北京航空航天大学航空科学与工程学院北京100191

基于二维编织C/SiC复合材料的细观结构,建立了碳纤维丝/热解碳界面/SiC基体和纤维束/表层SiC基体两种尺度下的细观单胞模型,通过有限元方法计算碳纤维丝/热解碳界面/SiC基体模型的等效弹性常数和强度,然后代入纤维束/表层SiC基体模型中... 详细信息

基于二维编织C/SiC复合材料的细观结构,建立了碳纤维丝/热解碳界面/SiC基体和纤维束/表层SiC基体两种尺度下的细观单胞模型,通过有限元方法计算碳纤维丝/热解碳界面/SiC基体模型的等效弹性常数和强度,然后代入纤维束/表层SiC基体模型中计算,并引入Tsai-Wu失效准则,考虑不同失效模式的损伤,建立了二维编织C/SiC复合材料的渐进损伤模型,模拟了其偏轴拉伸应力-应变行为。针对该模型,阐述了二维编织C/SiC复合材料单胞模型在复杂应力状态下其纤维束的损伤过程。数值模拟结果与实验数据吻合较好,验证了模型的有效性,为该种材料的力学性能分析提供了一种有效方法。

关键词：二维编织陶瓷基复合材料力学性能多尺度分析渐进损伤有限元法

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二维编织C/SiC复合材料板疲劳损伤分析

北京航空航天大学学报 2019年第1期45卷 192-199页

作者：陈天雄张铮王奇志林彗星北京航空航天大学航空科学与工程学院北京100083

为探索复合材料损伤的基本规律,首先,基于损伤力学,结合Tsai-Hill强度理论,提出了表征二维编织C/SiC复合材料损伤各向异性的损伤演化方程;然后,在商业有限元软件ANSYS环境中进行了二次开发,形成了考虑材料刚度随损伤折减的损伤模拟程序... 详细信息

为探索复合材料损伤的基本规律,首先,基于损伤力学,结合Tsai-Hill强度理论,提出了表征二维编织C/SiC复合材料损伤各向异性的损伤演化方程;然后,在商业有限元软件ANSYS环境中进行了二次开发,形成了考虑材料刚度随损伤折减的损伤模拟程序;其次,对二维编织C/SiC复合材料板模型进行了损伤模拟分析,结果表明材料损伤过程中应力与损伤度对单元破坏起共同作用;最后,对损伤演化方程的形式提出了讨论与改进,并通过模拟计算揭示了复合材料在损伤驱动力及材料特性作用下损伤呈现各向异性演化的特征,说明材料各向异性损伤是其材料特性及受载形式产生的必然结果。

关键词：复合材料二维编织损伤各向异性有限元

The virulence and vaccine strains of Streptococcus *** different influence to phagocytosis and cytokine secretion of macrophage

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The virulence and vaccine strains of Streptococcus *** diffe...