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Rickettsia-like organism infection associated with mass mortalities of blood clam, Tegillarca granosa, in the Yueqing Bay in China

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Acta Oceanologica Sinica 2012年第1期31卷 106-115页

作者： ZHU Zewen XU Ting he zhongyang WU Xinzhong WU Liuji MENG Qingguo Laboratory of Marine Life Science and Technology College of Animal SciencesZhejiang UniversityHangzhou 310029China Fisheries Technical Extension Center of Zhejiang Province Hangzhou 310012China

A series of mass mortalities of the cultured blood clam, Tegillarca granosa, occurred in the Yueqing Bay of China from 2005 to 2009. An obligate intracellular prokaryote, designated as rickettsia-like organism （RLO）, was frequently found in the moribund or dead blood clam sample during ultra- structural examination. These organisms were usually round, ellipsoid or occasionally dumbbell- shaped, ranged from approximately 0.28 to 0.71 #m in size and had a trilaminar cell wall. Two reproductive modes of organisms, transverse binary fission and budding, were observed. The or- ganisms were able to form eosinophilic inclusions. Most inclusions were found within epithelial and connective tissues of the mantle, gills and digestive tube. The biological and morphological char- acteristics indicate that these organisms may belong to the family Rickettsiaceae. RLOs exhibited significant pathogenicity. Cytopathological examinations revealed extensive necrosis and destruc- tion in the infected cell. The degree of tissue destruction was positively related to the number of RLO inclusions in the tissues, and the cytopathological effects were positively related to the number of intracellular RLO. RLOs and their inclusions were discovered throughout different disease areas and in different time periods. The infection intensity of the RLOs was positively correlated with the mortality rate of clams. Therefore, RLO infection might be associated with mass mortalities of cultured blood clams in the Yueqing Bay.

关键词： blood clam Tegillarca granosa rickettsia-like organism (RLO) inclusions mass mortalities

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Crystallographic Characterization and Themal Decomposition Behavior of High-Purity Microcrystalline Magnesite

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China's Refractories 2012年第3期21卷 25-28页

作者： he zhongyang MA Letian LIU Baikuan PRCO Beijing Science and Technology R&D Center Beijing 101300 China Haicheng Huayin New Materials Manufacturing Co. Ltd. Haicheng 114231 China

The intergranular cracking face is smooth and Iransgranular cracking fracture shows trace of cleavage. It is hard to .tirol characteristic rhombus in the dense small crystals. As measured by SEM, the particle size of microcrystalline magnesite originating in Sichuan - Tibet is uniform, most grains range in 2 -4 μm. Three-dimensional （ 3D ） crystal morphology assumes cubic or column.

关键词： microcrystalline macrocrystalline magnesite crystal morphology crystal size

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Effect of Carbon Source on Crystal Morphology of SiC in-situ Formed in AI_2O_3-Si-C Matrix

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China's Refractories 2015年第2期24卷 11-15页

作者： LIANG Feng LI Nan LIU Baikuan he zhongyang The State Key Laboratory of Refractories and Metallurgy Wuhan University of Science and Technology Puyang Refractories Group Co. Ltd.

Three kinds of Al2O3- Si- C matrix specimens were prepared using tabular corundum powder and Si powder as starting materials,ultrafine flake graphite,nano carbon black,and carbon nanotubes as carbon sources,respectively,to research the effect of micro or nano carbon materials on structure and morphology of formed Si C crystals. The specimens were fired at 1 000,1 200 and 1 400℃ for 3 h in carbon-embedded condition,*** phase composition was studied by XRD and the crystal morphology of Si C was investigated by FESEM. The results show that：（ 1） the amount of Si C increases with the firing temperature rising;（ 2） the in-situ reaction mechanism and the formed Si C crystal morphology vary with carbon source： carbon nanotubes are generally converted into Si C whiskers by carbon nanotubes-confined reaction; Si and nano carbon black react to nucleate quickly,and the nucleated Si C crystals grow evenly in all directions forming Si C particles; Si C whiskers are produced from edge to internal of ultrafine flake graphite.

关键词： alumina-silicon-carbon ultrafine flake graphite nano carbon black carbon nanotubes silicon carbide whiskers in-situ reaction

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Antioxidant Coating of SEN for Thin Slab Con-casting

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China's Refractories 2008年第2期17卷 22-24页

作者： PENG Dejiang he zhongyang LIU Baikuan Puyang Refractories Group Co. Ltd. Puyang 457100 China

The SEN for thin slab con-casting is easy to break and damage because of the oxidation during preheating and application. The enamel coating material is generally applied on the surface of SEN to avoid the oxidation. The coating material with born glass and silicon as main starting materials and silica sol as binder was studied. ZrO2 - C and Al2O3 - C materials containing 15% carbon were isostatic pressed, and heated at 600 ℃ , 900 ℃ , 1 200 ℃ , 1 500 ℃ for 2 h, respectively. The results show that the coating material with 70% of boron glass and 30% of silicon bonded by silica sol can form denser protection layer in the above mentioned materials at the range of 600 -1 500 ℃. The oxidation area ratio and weight loss ratio with the coating are much lower than those without the coating.

关键词： Oxidation Boron glass Coating Thin slab con-casting

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Effect of Nano-CaCo_3 on Properties and Microstructure of Corundum Based Castables

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China's Refractories 2010年第4期19卷 21-24页

作者： ZHANG Houxing he zhongyang GAN Mingliang LIU Baikuan Puyang Refractories Group Co. Ltd.（PRCO） Puyang 457100 China

The chrome-containing corundum castables specimens with different nano-CaCO3 additions （0-1.6 wt%） were prepared using tabular corundum,alumina powder,chrome oxide micropowder （average particle size 〈 5 μm）,calcium aluminate cement （Secar71）,commercial nano-CaCO3 （average particle size 〈100 nm） as main starting materials and FS10 as water reducer. The specimens heat treated at 1 000 ℃ and 1 600 ℃ were characterized in terms of apparent porosity,bulk density,cold and hot strengths,and microstructure. The results show that,when the nano-CaCO3 addition is no more than 1.0 wt%,the apparent porosity of the castables increases with nano-CaCO3 addition increasing,both the cold and hot strengths are enhanced; however,when the nano-CaCO3 addition excesses 1.0 wt%,both the cold and hot strengths go down remarkably with nano-CaCO3 addition increasing; the thermal shock resistance is gradually improved with nano-CaCO3 addition increasing in chosen range.

关键词： Corundum based castables Nanometer calcium carbonate Mechanical properties Microstructure

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Ongoing Technology and Developing Trend of Ar-blowing Purging Plug

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China's Refractories 2008年第4期17卷 21-24页

作者： he zhongyang WANG Fenggang LIU Baikuan SHI Xubo Puyang Refractories Group Co. Ltd. （PRCO） Puyang 457100 China

An introduction of the ongoing technology of argon-blowing purging plugs in China was presented in this work. Gel powders were used as starting materials to enhance the high temperature mechanical properties of the purging plugs. Composite purging plug adopting extrusion formed gas-purging bar and slit had its surface structural design improved, which enhanced the resistances to thermal shock and molten steel penetration, prolonging the service life. In addition, the safety was greatly improved by upgrading the framework and production process, enhancing the resistance to breakout. It is indicated that the developing trend is to produce purging plugs of longer service life and better gas purging rate with different starting materials and structure designs to meet the requirements of various metallurgical processes.

关键词： Gas-purging bar Composite purging plugs Gel powder Breakout Molten steel penetration resistance

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Effects of Dietary Soy Protein Concentrate on Growth, Digestive Enzymes Activities and Target of Rapamycin Signaling Pathway Regulation in Juvenile Soft-Shelled Turtle, <i>Pelodiscus sinensis</i>

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Agricultural Sciences 2015年第3期6卷 335-345页

作者： Fan Zhou Yaqin Wang Li Tang Yong Huang Xueyan Ding zhongyang he Zhejiang Fisheries Technical Extension Station Hangzhou China College of Agriculture and Biotechnology Zhejiang University Hangzhou China College of Animal Sciences Zhejiang University Hangzhou China

Soft-shelled turtle, Pelodiscus sinensis is important aquatic species in China, and searching for alternatives protein resources to fish meal (FM)-based feeds in feed has become urgent and important for its sustainability development. The present study was conducted to assess the effects of dietary soy protein concentrate (SPC) on growth, digestive enzymes and target of rapamycin (TOR) signaling pathway of juvenile P. sinensis (4.56 ± 0.09 g). SPC was applied to replace FM protein at 0%, 15%, 30% and 60% (designated as T0, T15, T30 and T60, respectively), and each diet was fed to triplicate groups. The results showed that there was no significant difference in growth performance and feed utilization except of the turtles fed with T60 diet, of which showed poorer daily weight gain and feed conversion rate. The pepsin/trypsin and Na+-K+ ATP-ase activities decreased dramatically when SPC level increased, and lipase activities in liver and intestinal tract also showed decline tendency. However, amylase activities were unaffected. No significant differences were observed in TOR, S6K1 and 4E-BP1 genes mRNA expression level of TOR signaling pathway among the treatments. However, the relative phosphorylated level of these proteins decreased significantly when SPC level increased. The present study indicated that high SPC substitution level would suppress digestive enzymes and TOR signaling pathway proteins phosphorylated level and eventually result in growth reduction of P. sinensis.

关键词： Soft-Shelled Turtle P. sinensis Soy Protein Concentrate Growth Performance Digestive Enzymes Target of Rapamycin Signaling Pathway

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连铸用功能耐火材料的现状及发展趋势

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耐火材料 2011年第6期45卷 462-465,474页

作者：贺中央濮阳濮耐高温材料(集团)股份有限公司河南濮阳457100

介绍了钢包底吹氩透气砖、滑动水口、连铸三大件和ZrO2质水口等连铸用功能耐火材料的现状及发展趋势,认为:现代连铸生产工艺对连铸用功能耐火材料长寿命和高适应性的要求越来越高,单一材质体系很难满足要求;根据产品不同部位的损毁方式... 详细信息

介绍了钢包底吹氩透气砖、滑动水口、连铸三大件和ZrO2质水口等连铸用功能耐火材料的现状及发展趋势,认为:现代连铸生产工艺对连铸用功能耐火材料长寿命和高适应性的要求越来越高,单一材质体系很难满足要求;根据产品不同部位的损毁方式和特点及浇铸钢种和冶炼工艺的不同,针对性地研发新材料将是连铸用功能耐火材料发展的现实要求;从材质发展的角度来看,连铸用功能耐火材料的材质向多样化、复合化发展将是必然的趋势。

关键词：连铸功能耐火材料透气砖滑动水口连铸三大件 ZrO2质水口

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薄板坯中间包镁质喷涂料的侵蚀机理

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耐火材料 2007年第4期41卷 267-270页

作者：贺中央黄江文宋世锋濮阳濮耐高温材料有限公司濮阳457100

借助SEM、EDS、XRD等分析手段,观察和分析了用后中间包镁质喷涂料的显微结构,研究了镁质喷涂料的侵蚀机理。结果表明:在研究条件下,以烧结镁砂为主要原料的镁质喷涂料基质中低熔物与渗入的熔渣中的Al、Si、Ca、Fe反应生成复杂的钙铝铁... 详细信息

借助SEM、EDS、XRD等分析手段,观察和分析了用后中间包镁质喷涂料的显微结构,研究了镁质喷涂料的侵蚀机理。结果表明:在研究条件下,以烧结镁砂为主要原料的镁质喷涂料基质中低熔物与渗入的熔渣中的Al、Si、Ca、Fe反应生成复杂的钙铝铁硅酸盐,形成粘度适中的液相向原质层渗透,在使用温度梯度下形成一层致密层,阻止渣往涂料深处进一步渗透,提高了材料的抗侵蚀性能,实现涂料的长寿命;钢渣中的Fe、Mn、Si与MgO形成橄榄石固溶体,对涂料的抗侵蚀性能有一定贡献。

关键词：镁质喷涂料渗透致密层渣蚀层显微结构

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气调包装对中华鳖品质的影响

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中国食品学报 2017年第12期17卷 149-154页

作者：陈师师薛静何中央王宏海何欣戴志远浙江工商大学海洋食品研究院杭州310012 浙江省水产技术推广总站杭州311100 浙江省水产品加工技术研究联合重点实验室杭州310012

以中华鳖为研究对象,采用不同气调包装处理中华鳖,测定其在(4±1)℃贮藏过程中微生物、理化指标的变化情况,评价气调包装(M_1:30%CO_2/70%N_2;M_2:50%CO_2/50%N_2;M3:70%CO_2/30%N_2)对中华鳖品质的影响,并以空气包装和真空包装为对照... 详细信息

以中华鳖为研究对象,采用不同气调包装处理中华鳖,测定其在(4±1)℃贮藏过程中微生物、理化指标的变化情况,评价气调包装(M_1:30%CO_2/70%N_2;M_2:50%CO_2/50%N_2;M3:70%CO_2/30%N_2)对中华鳖品质的影响,并以空气包装和真空包装为对照组。结果表明:相比空气和真空包装而言,气调包装(M_1、M_2、M3)有效抑制了微生物的生长繁殖,延缓中华鳖的腐败变质;中华鳖气调包装最适气体配比为50%CO_2/50%N_2,其货架期可达18 d。

关键词：中华鳖气调包装微生物货架期

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