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Microstructures and Hardness of 8CrWMoV Steel with Multiple Types of Ultra Fine Carbides

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材料热处理学报 2004年第5期25卷 279-283页

作者： DAIyu-mei ZHANGZhan-ping MAYong-qing QIyu-hong LIUyan-xia yuTao Instituteofmaterialsandtechnology DalianMaritimeUniversityDalian116026

The structure and hardness of 8CrWMoV steel with multiple types of ultra fine carbides are studied after annealing, quenching and tempering in this paper. The results show that multiple types of carbides M3C, M7C3, M23C6, M6C and MC were observed in the annealed steel. Nucleation and coalescence of new carbides, partial dissolution of original carbides in γ phase region during annealing at 800～840℃, result in ultra-fine carbides. Average size of the carbides is0.33～0.34μm in the steel annealed at 800～840℃. Because M3C and M23C6 dissolve easily in austenite, the high hardness HRC63～65 can be obtained by quenching at 840～860℃. Un-dissolved carbides M6C and MC (VC) can effectively prevent the coarsening of austenitic grain, and conduce to obtain very fine martensite. The retained austenite can be easy to decompose during tempering at low and middle temperature due to the precipitation of multiple types of carbides and the good tempering-resistance of the steel is obtained. The microstructure and property of the steel after heat treatment can be accurately explained by calculating based on phase equilibrium *** Words: 8CrWMoV steel, ultra-fine carbide, heat treatment, microstructure,

关键词：显微结构 8CrWMoV钢超细硬质合金硬度热处理

Sodium valproate induces mitochondria-dependent apoptosis in human hepatoblastoma cells

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Chinese Medical Journal 2011年第14期000卷 2167-2172页

作者： WANG Wei LIAO xiao-li CHEN Jing-hong LI Dan-dan LIN Chun-lan yan yu-xia TANG yu-hui JIANG Jian-wei Department of Biochemistry Medical College of Jinan UniversityGuangzhou Guangdong 510632 China State Key Laboratory of Oncology in Southern China Cancer Center Sun Yat-sen University Guangzhou Guangdong 510060China Department of Biochemistry Guangzhou University of Chinese Medicine Guangzhou Guangdong 510006 China

Background Sodium valproate inhibits proliferation in neuroblastoma and glioma cells, and inhibits proliferation and induces apoptosis in hepatoblastoma cells. Information describing the molecular pathways of the antitumor effects of sodium valproate is limited; therefore, we explored the mechanisms of action of sodium valproate in the human hepatoblastoma cell line, *** The effects of sodium valproate on the proliferation of HepG2 cells were evaluated by the Walsh-sohema transform and colony formation assays. Sodium valproate-induced apoptosis in HepG2 cells was investigated with fluorescence microscopy to detect morphological changes; by flow cytometry to calculate DNA ploidy and apoptotic cell percentages; with Western blotting analyses to determine c-Jun N-terminal kinases （JNK）, p-JNK, Bcl-2, Bax, and caspase-3 and-9 protein expression levels; and using JC-1 fluorescence microscopy to detect the membrane potential of mitochondria. Statistical analyses were performed using one-way analysis of variance by SPSS 13.0 *** Our results indicated that sodium valproate treatment inhibited the proliferation of HepG2 cells in a dose-dependent manner. Sodium valproate induced apoptosis in HepG2 cells as it： caused morphologic changes associated with apoptosis, including condensed and fragmented chromatin; increased the percentage of hypodiploid cells in a dose-dependent manner; increased the percentage of annexin Ⅴ-positive/propidium iodide-negative cells from 9.52％ to 74.87％; decreased JNK and increased phosphate-JNK protein expression levels; reduced the membrane potential of mitochondria; decreased the ratio of Bcl-2/Bax; and activated caspases-3 *** Sodium valproate inhibited the proliferation of HepG2 cells, triggered mitochondria-dependent HepG2 cell apoptosis and activated JNK.

关键词： hepatoblastoma sodium valproate c-Jun N-terminal kinases mitochondria apoptosis

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“粉圈文化”对小学生行为模式的误导与纠偏

教学与管理 2020年第8期 10-12页

作者：闫玉霞山东滨州市惠民县第一实验学校

近年来,追星成为了青少年教育中的新问题,由追星也产生了一系列亚文化,“粉圈文化”就是其中之一,其不仅仅颠覆了教育中的传统价值观,还扭曲了小学生对好恶、善恶、是非等一系列价值的判断,这一现象必须引起教育者的重视。教师可以从日... 详细信息

近年来,追星成为了青少年教育中的新问题,由追星也产生了一系列亚文化,“粉圈文化”就是其中之一,其不仅仅颠覆了教育中的传统价值观,还扭曲了小学生对好恶、善恶、是非等一系列价值的判断,这一现象必须引起教育者的重视。教师可以从日常关怀、家校联合、心理满足三方面入手,三管齐下纠正小学生的错误行为。

关键词： “粉圈文化” 基础教育小学生行为模式

Protective Effects of Rumen Protected Choline in Dairy Cows

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Animal Husbandry and Feed Science 2010年第4期2卷 26-28,31页

作者： xiaO Jin GAO yan-xia CAO yu-feng LI Qiu-feng LI Jian-guo College of Animal Science and Technology Agricultural University of Hebei Baoding 071000 China

Choline is a necessary nutrient for dairy cows and contributes to milk yield, but most of dietary choline can be degraded by the microorganisms in rumen. Rumen protected choline （RPC） has been developed to protect choline from degradation. To screen stable RPC, choline chloride was coated with acrylic resin no. IV, chitosan and the mixture containing the two lagging covers by fluidized bed coating technology, respectively. Their stability was evaluated in vitro and in situ. The results showed that release rate of RPC coated with acrylic resin no. IV and chitosan was the lowest in rumen and pH 6.6 buffer. And its effective protection rate reached 62.04% in rumen. Therefore, RPC coated with acrylic resin no. IV and chitosan has good stability and protection efficacy in rumen, and it can be used in practice to supply effective choline for the ruminant.

关键词： Rumen protected choline Holstein cows Release rate

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一种特殊的非均匀水声阵列稀疏重构方法

舰船科学技术 2018年第3期40卷 132-136,149页

作者：严雨霞王彪江苏科技大学电子信息学院江苏镇江212003 水声对抗技术重点实验室北京100094

为了提高阵元的利用率和水下目标的测向精度,提出了一种特殊的非均匀水声阵列稀疏重构方法。利用2个均匀线性子阵列组成一个非均匀线性阵列作为信号的接收阵列,经过角度划分的非均匀线阵阵列流型阵作为观测阵,采用观测矩阵对信号进行投... 详细信息

为了提高阵元的利用率和水下目标的测向精度,提出了一种特殊的非均匀水声阵列稀疏重构方法。利用2个均匀线性子阵列组成一个非均匀线性阵列作为信号的接收阵列,经过角度划分的非均匀线阵阵列流型阵作为观测阵,采用观测矩阵对信号进行投影测量得到观测值,从观测值中重构原信号进而得到方位信息。在相同分辨条件下,非均匀水声阵列技术可利用更少的阵元来识别更多的水下目标,因而极大地降低传统水声阵列的复杂度。在低先验知识、低信噪比条件下,提高了水声阵列的测向精度。

关键词：非均匀线阵压缩感知稀疏重构波达方向角估计

能量多普勒超声在人体鱼序列综合征产前诊断中的应用研究

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四川大学学报（医学版） 2011年第6期42卷 870-873页

作者：严霞瑜杨太珠罗红田雨杨帆四川大学华西第二医院超声科成都610041

目的探讨人体鱼序列综合征胎儿的产前腹主动脉能量多普勒超声表现及应用价值。方法应用能量多普勒对2例人体鱼序列综合征胎儿和10例正常胎儿行腹主动脉二维能量多普勒超声检查及三维能量多普勒超声重建。结果二维能量多普勒超声检查及... 详细信息

目的探讨人体鱼序列综合征胎儿的产前腹主动脉能量多普勒超声表现及应用价值。方法应用能量多普勒对2例人体鱼序列综合征胎儿和10例正常胎儿行腹主动脉二维能量多普勒超声检查及三维能量多普勒超声重建。结果二维能量多普勒超声检查及三维能量多普勒超声重建显示:正常胎儿腹主动脉在肾水平分出双侧肾动脉,在盆腔分为左、右髂总动脉;人体鱼序列综合征胎儿腹主动脉及其分支具有如下特点:①起自高位腹主动脉的粗大畸形血管,追查畸形血管,发现其充当脐动脉;②无肾动脉分支;③无髂总动脉分支;④腹主动脉在分出畸形血管后变细小。结论人体鱼序列综合征胎儿的腹主动脉有特征性的能量多普勒超声改变,应用二维能量多普勒超声及三维能量多普勒超声有助于产前诊断人体鱼序列综合征。

关键词：能量多普勒超声产前诊断人体鱼序列综合征

Silk damping in scalar-induced gravitational waves: a novel probe for new physics

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 79-85页

作者： yan-Heng yu Sai Wang Theoretical Physics Division Institute of High Energy Physics Chinese Academy of Sciences School of Physics University of Chinese Academy of Sciences

Silk damping is well known in the study of cosmic microwave background（CMB） and accounts for suppression of the angular power spectrum of CMB on large angular multipoles. In this article, we study the effect of Silk damping on the scalar-induced gravitational waves（SIGWs）. Resulting from the dissipation of cosmic fluid, the Silk damping notably suppresses the energydensity spectrum of SIGWs on scales comparable to a diffusion scale at the decoupling time of weakly-interacting particles. The effect offers a novel observable for probing the underlying particle interaction, especially for those mediated by heavy gauge bosons beyond the standard model of particles. We anticipate that pulsar timing arrays are sensitive to gauge bosons with mass ～10～3-10～4 GeV, while space-and ground-based interferometers to those with mass ～10～7-1012GeV, leading to essential complements to on-going and future experiments of high-energy physics.

关键词： scalar-induced gravitational waves Silk damping new physics

罕见女性生殖系统骨外尤文肉瘤的超声图像特征

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四川大学学报（医学版） 2021年第1期52卷 149-152页

作者：胡莎严霞瑜何敏罗红四川大学华西第二医院超声科成都610041 出生缺陷与相关妇儿疾病教育部重点实验室(四川大学) 成都610041

目的研究女性生殖系统骨外尤文肉瘤的临床特点及超声图像特征,探讨超声对于女性生殖系统骨外尤文肉瘤的诊断价值。方法回顾性分析2009年6月-2019年6月期间在我院经手术-病理证实的女性盆腔内尤文肉瘤的临床资料及超声表现,总结女性生殖... 详细信息

目的研究女性生殖系统骨外尤文肉瘤的临床特点及超声图像特征,探讨超声对于女性生殖系统骨外尤文肉瘤的诊断价值。方法回顾性分析2009年6月-2019年6月期间在我院经手术-病理证实的女性盆腔内尤文肉瘤的临床资料及超声表现,总结女性生殖系统骨外尤文肉瘤的临床特点及超声图像特征,提出超声对此类疾病的诊断思路。结果 10年间我院收治的经手术-病理确诊的女性生殖系统骨外尤文肉瘤患者共13例,患者年龄8月~40岁,无特异性临床症状,部分患者肿瘤标记物检测出现CA125升高。13例患者中共发现病灶19个,累及生殖系统病灶为16个,主要表现为回声不均匀的低回声实性占位或囊实性占位,体积较大,形态不规则,边界不清;少数患者可伴腹水;多数病灶血供为中量~丰富血流,以低阻血流为主,极少数病灶可能乏血供。所有病灶在术前均未能进行准确定性诊断。结论女性生殖系统骨外尤文肉瘤术前定性诊断极困难,如遇边界欠清、形态欠规则的不均质低回声团块或宫体查见不均匀的回声减低团块时一定警惕骨外尤文肉瘤的可能,但最终的定性诊断仍需结合患者的病理检查结果。

关键词：生殖系统骨外尤文肉瘤临床超声

高职院校共青团服务大学生创业研究——以河南省高职院校为例

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广东青年职业学院学报 2017年第2期31卷 69-74页

作者：燕玉霞河南工业贸易职业学院贸易经济系河南郑州451191

随着就业形势的日益严峻,党的十七大报告指出要以创业引领就业,其中大学生创业已成为一支重要的力量。高校共青团作为共青团在高校的基层组织,一直是党的助手和后备军,因此共青团促进大学生创业责无旁贷。但共青团的创业服务功能并没有... 详细信息

随着就业形势的日益严峻,党的十七大报告指出要以创业引领就业,其中大学生创业已成为一支重要的力量。高校共青团作为共青团在高校的基层组织,一直是党的助手和后备军,因此共青团促进大学生创业责无旁贷。但共青团的创业服务功能并没有真正发挥,学生对其的创业职能认识尚不足,共青团的专门创业指导人才匮乏,创业资金不足,创业平台建设落后等。为了更好地发挥共青团的创业服务功能,应加强宣传共青团的创业服务功能,明确服务定位,多方筹措资金,积极兴建创业平台。

关键词：高校共青团创业服务定位平台建设