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Development and Application of Die-Casting High Speed Steel Rolls

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Journal of Iron and Steel Research International 2005年第1期12卷 22-27页

作者： JIANGZhi-qiang FUHan-guang dingyu-cheng ZhengzhouInstituteofAeronautics Zhengzhou450015China Xi＇anJiaotongUniversity Xi＇an710049China Xi＇anJiaotongUniversity Xi＇an710049China／／ZhengzhouInstituteofAeronauticsZhengzhou450015China

Due to its high hardness,good red hardness and excellent wear resistance at high temperature,high speed steel(HSS)is fit for the roll *** order to overcome the segregation of centrifugal casting of HSS roll,die-cast processes were developed and its effects on the properties of the HSS roll were *** was found that pressure,pressing time and speed are three important factors affecting shrinkage *** pouring temperature of 1 400-1 450 ℃,pressure of 150-160 MPa,pressing time of 120-150 sand pressing speed of 14-16mm/s,a compact HSS roll was obtained,which has no segregation and small working *** the high speed wire rod rolling mill,service life of the HSS roll is 5to 8times longer than that of high nickel chromium infinite chilled cast iron roll.

关键词： high speed steel roll die-cast shrinkage

Three-Dirac-fermion approach to unexpected universal gapless surface states in van der Waals magnetic topological insulators

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中国科学:物理学、力学、天文学英文版 2023年第9期66卷 79-85页

作者： Dinghui Wang Huaiqiang Wang dingyu Xing Haijun Zhang National Laboratory of Solid State Microstructures School of PhysicsNanjing UniversityNanjing 210093China Collaborative Innovation Center of Advanced Microstructures Nanjing UniversityNanjing 210093China

Layered van der Waals(vdW) topological materials, especially the recently discovered MnBi_(2)Te_(4)-family magnetic topological insulators(TIs), have aroused great attention. However, there has been a serious debate about whether the surface states are gapped or gapless for antiferromagnetic(AFM) TI MnBi_(2)Te_(4), which is crucial to the prospect of various magnetic topological phenomena. Here, a minimal three-Dirac-fermion approach is developed to generally describe topological surface states of nonmagnetic/magnetic vdW TIs under the modulation of the interlayer vdW gap. In particular, this approach is applied to address the controversial issues concerning the surface states of vdW AFM TIs. Remarkably, topologically protected gapless Dirac-cone surface states are found to arise due to a small expansion of the interlayer vdW gap on the surface, when the Chern number equals zero for the surface ferromagnetic layer;while the surface states remain gapped in all other cases. These results are further confirmed by our first-principles calculations on AFM TI MnBi_(2)Te_(4). The theorectically discovered gapless Dirac-cone states provide a unique mechanism for understanding the puzzle of the experimentally observed gapless surface states in MnBi_(2)Te_(4).This work also provides a promising way for experiments to realize the intrinsic magnetic quantum anomalous Hall efect in MnBi_(2)Te_(4) films with a large energy gap.

关键词： magnetic topological insulator van der Waals gap Dirac-fermion model gapless surface state

PLX8394,a RAF inhibitor,inhibits enterovirus 71 replication by blocking RAF/MEK/ERK signaling

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Virologica Sinica 2023年第2期38卷 276-284页

作者： Chengyuan Wu Guangyan Zhu Fang Qiu Fuli Ren Binbin Lin dingyu Zhang Qingyu yang Chaolin Huang Wuhan Jinyintan Hospital Tongji Medical College of Huazhong University of Science and TechnologyWuhan430023China State Key Laboratory of Virology Wuhan Institute of VirologyChinese Academy of SciencesWuhan430071China Division of Life Sciences and Medicine University of Science and Technology of ChinaHefei230027China

Enterovirus 71(EV71)poses a serious threat to human health,with scattered outbreaks *** are several vaccines against a few EV71 strains but no efficient drug for the treatment of EV71 ***,it is urgent and of significance to develop anti-EV71 ***,we found that PLX8394,a RAF inhibitor,possesses high antiviral activity against EV71 in vitro,being superior to the traditional clinical drug ***,PLX8394 exhibits broad-spectrum antiviral activity against ***,in a suckling mouse model,PLX8394 provided a 70%protection rate for EV71-infected mice,reduced the viral load in liver and heart tissues,and relieved the inflammatory response.A mechanistic study showed that PLX8394 inhibited EV71 by suppressing the RAF/MEK/ERK signaling ***,PLX8394 lays a foundation for the development of new drugs against EV71.

关键词： Enterovirus 71(EV71) RAF inhibitor Hand,foot,and mouth disease(HFMD) RAF/MEK/ERK signaling Pathway Antiviral agents

灰枣和冬枣果实质地差异的解剖学观察及相关酶活性研究

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果树学报 2024年第9期41卷 1811-1820页

作者：屈丝雨任甜樊丁宇郝庆李亚兰新疆农业大学林学与风景园林学院乌鲁木齐830000 新疆农业科学院园艺作物研究所乌鲁木齐830000

【目的】以果实质地差异明显的两个枣品种为试验材料,观察其发育过程中果肉细胞的显微结构,测定果实的含水量、硬度及细胞壁相关代谢酶的活性,并进行相关性分析,探究影响两种质地形成的关键因素。【方法】分别以灰枣(制干枣)和冬枣(鲜食... 详细信息

【目的】以果实质地差异明显的两个枣品种为试验材料,观察其发育过程中果肉细胞的显微结构,测定果实的含水量、硬度及细胞壁相关代谢酶的活性,并进行相关性分析,探究影响两种质地形成的关键因素。【方法】分别以灰枣(制干枣)和冬枣(鲜食枣)花后31(S1)、63(S2)、78(S3)、98(S4)和108 d(S5)的果实为试验材料,对果实发育过程中含水率、硬度,果肉细胞形态、细胞壁组分及代谢酶活性进行动态分析。【结果】(1)随着果实发育,灰枣和冬枣的含水率均呈先升高后下降的趋势,硬度均呈下降趋势,且灰枣硬度持续高于冬枣。(2)两个品种果肉细胞的变化均呈现先迅速增大后缓慢增大的趋势,但冬枣果肉薄壁细胞面积大于灰枣。(3)果肉细胞超显微结构观测显示,在S5时期,两个品种果肉细胞壁、中胶层已经明显降解,但冬枣相较灰枣其中胶层、内含物降解较慢。(4)两个品种总果胶以及纤维素含量整体呈逐渐降低趋势,且冬枣一直低于灰枣。(5)果实硬度与总果胶和纤维素含量呈显著正相关,与β-半乳糖苷酶(β-Gal)、α-L-阿拉伯呋喃糖苷酶(α-Af)、果胶裂解酶(PL)活性呈极显著负相关,多聚半乳糖醛酸酶(PG)活性与冬枣果实硬度、水分含量的相关性均极显著,但与灰枣相关性不显著。【结论】灰枣和冬枣质地品质的差异与细胞壁组分总果胶及纤维素含量、果肉细胞显微结构的差异相关,还与细胞壁代谢相关酶β-Gal、α-Af、PL有关,此外,PG在冬枣质地变化中也发挥关键作用。

关键词：枣果实质地细胞解剖细胞壁组分细胞壁代谢相关酶

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全电子目标控制器通信单元设计方案研究

铁路计算机应用 2024年第9期33卷 78-83页

作者：张夫松王鼎宇邢琦北京全路通信信号研究设计院集团有限公司北京100070

全电子计算机联锁系统逻辑部(简称:逻辑部)与全电子目标控制器间数据通信量大,对通信的安全性、可靠性和实时性等要求极高,为此,提出了基于二乘二取二架构的全电子目标控制器通信单元(简称:通信单元)设计方案。文章阐述了通信单元设计... 详细信息

全电子计算机联锁系统逻辑部(简称:逻辑部)与全电子目标控制器间数据通信量大,对通信的安全性、可靠性和实时性等要求极高,为此,提出了基于二乘二取二架构的全电子目标控制器通信单元(简称:通信单元)设计方案。文章阐述了通信单元设计、软件功能,以及通信网络拓扑设计、通信协议设计、安全处理措施等,并进行了方案验证。验证结果表明,通信单元与逻辑部间的通信数据完整,通信质量稳定,满足设计要求。

关键词：通信单元全电子目标控制器全电子执行单元通信网络拓扑安全处理

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灰枣及其芽变品种果实品质评价

现代农业科技 2024年第16期 119-123,131页

作者：孔令硕樊丁宇靳娟杨磊郝庆田嘉新疆农业大学园艺学院新疆乌鲁木齐830052 新疆农业科学院新疆乌鲁木齐830052

以麦盖提县传统主栽灰枣为对照(CK),比较分析不同芽变品种果实质构、果实色差及果实内在品质的差异,并对果实内在品质进行主成分分析。结果表明:灰枣及其6个芽变品种的果实高度为2.04~2.21 cm,果实硬度为6.99~9.52 N,果实黏性为-0.13~-0... 详细信息

以麦盖提县传统主栽灰枣为对照(CK),比较分析不同芽变品种果实质构、果实色差及果实内在品质的差异,并对果实内在品质进行主成分分析。结果表明:灰枣及其6个芽变品种的果实高度为2.04~2.21 cm,果实硬度为6.99~9.52 N,果实黏性为-0.13~-0.07 N/s,果实黏聚性为0.24~0.41,果实咀嚼性为0.53~1.78 N,果实回复性为0.144~0.226;果实表皮L值变化范围为32.27~38.98,a值变化范围为16.31~26.00,b值变化范围为14.95~20.95,C值变化范围为24.90~31.58,h值变化范围为33.03~51.74;品种之间总酚与纤维素含量差异达到显著水平,可溶性糖、可滴定酸、黄酮、可溶性固形物和抗坏血酸含量差异均未达到显著水平;在果实品质指标中,部分指标间的相关性达到显著或极显著水平;第1主成分的特征值为4.462,贡献率为63.714%,第2主成分的特征值为1.208,贡献率为17.261%;灰枣及其6个芽变品种的综合评价排序为灰08-3>新丰1号>灰实2号>HF-1>CK>灰枣新1号>羌灰2号。

关键词：灰枣芽变品种果实品质综合评价

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Modelling and Dynamic Characteristics for a Non-metal Pressurized Reservoir with Variable Volume

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Chinese Journal of Mechanical Engineering 2022年第2期35卷 159-173页

作者： Pei Wang Jing Yao Baidong Feng Mandi Li dingyu Wang School of Mechanical Engineering Yanshan UniversityQinhuangdao 066004China Advanced Manufacturing Forming Technology and Equipment Qinhuangdao 066004China Hebei Provincial Key Laboratory of Heavy Fluid Power Transmission and Control Yanshan UniversityQinhuangdao 066004China

With the increasing demand to reduce emissions and save energy,hydraulic reservoirs require new architecture to optimize their weight,space,and *** open reservoirs are large,heavy,and easily polluted,and threaten the operation of hydraulic systems.A closed reservoir provides the advantages of small volume and light weight,compared to open *** this study,a non-metallic pressure reservoir with variable volume is designed and manufactured for closed-circuit hydraulic *** reservoir housing is made of rubber,and the Mooney-Rivlin model is chosen based on the rubber strain *** FEA simulation for the reservoir is performed using ANSYS Workbench to obtain the structural *** major contribution is the establishment of mathematical models for this reservoir,including the volume equation changing with height,flow equation,and force balance equation,to explore the output characteristics of this *** on these results,simulation models were built to analyze the output characteristics of the ***,the test rig of a conventional hydraulic system was transformed into a closed-circuit asymmetric hydraulic system for the reservoir,and preliminary verification experiments were conducted on *** results demonstrate that the designed reservoir can absorb and discharge oil and supercharge pump inlet to benefit system *** changes in the volume and pressure with displacements under different volume ratios and frequencies were obtained,which verified the accuracy of the mathematical *** to its lightweight design and small volume,the reservoir can replace conventional open reservoirs,and this lays a foundation for future theoretical research on this reservoir.

关键词： Hydraulic reservoir Variable volume Pressure reservoir Non-metal Lightweight

血清Claudin-5水平有利于早期预测重症急性胰腺炎:一项前瞻性观察性研究

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中华危重病急救医学 2024年第9期36卷 930-936页

作者：陈欣蕾王晖晖耿平凌冰玉马爱闻徐敏谈定玉江苏省苏北人民医院急诊医学科江苏扬州225001

目的探讨急性胰腺炎(AP)患者早期血清紧密连接蛋白Claudin-5水平在重症方面的预测价值。方法采用前瞻性观察性研究方法,纳入2021年12月1日至2022年11月30日在江苏省苏北人民医院确诊AP并收入院的患者,随机纳入同期符合条件的健康志愿者... 详细信息

目的探讨急性胰腺炎(AP)患者早期血清紧密连接蛋白Claudin-5水平在重症方面的预测价值。方法采用前瞻性观察性研究方法,纳入2021年12月1日至2022年11月30日在江苏省苏北人民医院确诊AP并收入院的患者,随机纳入同期符合条件的健康志愿者作为健康对照组。根据2012年亚特兰大分级标准将AP患者分为轻症急性胰腺炎(MAP)组、中度急性胰腺炎(MSAP)组和重症急性胰腺炎(SAP)组;再根据住院时间将SAP患者分为入院1、3、7 d亚组。收集所有入选者的基线资料,包括性别、年龄、基础疾病及可能病因;采用酶联免疫吸附试验(ELISA)检测各组入选者血清Claudin-5水平;通过院内检验查询系统获得各组AP患者其他血清学指标数据〔血细胞比容(HCT)、白蛋白(Alb)、血清Ca^(2+)、C-反应蛋白(CRP)、降钙素原(PCT)水平〕;记录各组AP患者改良Marshall评分(mMarshall)、改良CT严重程度指数(mCTSI)评分、急性胰腺炎床旁严重程度指数(BISAP)评分、急性生理学与慢性健康状况评分Ⅱ(APACHEⅡ)。分析并比较各组间上述指标的差异;采用Spearman相关法分析Claudin-5水平与各影响因素之间的相关性;绘制受试者工作特征曲线(ROC曲线)分析各影响因素对SAP的预测价值;采用多因素岭回归分析筛选SAP的独立危险因素。结果共纳入109例AP患者,其中MAP组66例,MSAP组15例,SAP组28例;同时有27例健康志愿者纳入健康对照组。各组入选者的性别和年龄比较差异均无统计学意义,3组AP患者在基础疾病和病因构成方面比较差异亦均无统计学意义。各组AP患者血清Claudin-5水平随病情加重呈明显升高趋势,且均显著高于健康对照组〔ng/L:888.58(574.52,1141.59)、3749.02(2784.93,5789.92)、4667.81(3935.21,7315.66)比291.13(250.19,314.75),均P<0.05〕。亚组分析显示,随病程延长,SAP组患者入院3 d的Claudin-5水平较入院1 d呈明显下降趋势〔ng/L:2052.59(1089.43,4006.47)比4667.81(3935.21,7315.66),P<0.05〕。Spearman相关性分析显示,AP患者血清Claudin-5水平与CRP、PCT、HCT及mMarshall、mCTSI、BISAP评分均呈显著正相关(r值分别为0.570、0.525、0.323、0.774、0.670、0.652,均P<0.001),与Alb呈显著负相关(r=-0.394,P<0.001)。而AP患者随病情加重HCT水平呈明显上升趋势,Alb水平呈明显下降趋势;SAP患者经治疗后上述现象有改善倾向,间接表明血清Claudin-5水平正向反映血管渗漏。ROC曲线分析显示,AP患者血清Claudin-5水平早期预测SAP的准确性最高,ROC曲线下面积(AUC)为0.948,当血清Claudin-5≥2997 ng/L时,早期筛查SAP的敏感度为100%,特异度为88.89%。多因素岭回归分析显示,血清Claudin-5、PCT水平和APACHEⅡ评分可作为早期预测SAP的独立危险因素(均P<0.05)。结论血清Claudin-5水平有利于早期预测SAP,并与炎症反应和血管渗漏密切相关。

关键词：紧密连接蛋白Claudin-5 急性胰腺炎重症早期评估

人脐带间充质干细胞对糖尿病肾病大鼠肠道屏障功能的调节作用

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中国组织工程研究 2024年第19期28卷 2967-2973页

作者：吴雅茹米焱魏凯悦高和平张丁予王彩丽内蒙古科技大学包头医学院内蒙古自治区包头市014000 内蒙古科技大学包头医学院第一附属医院肾内科内蒙古自治区包头市014000

背景:糖尿病肾病是引起终末期肾病的重要原因,其中肠道屏障损伤在糖尿病肾病的发生发展中起到了重要作用。目的:观察人脐带间充质干细胞对糖尿病肾病大鼠肠道屏障的保护作用。方法:30只8周龄雄性SD大鼠随机分配至健康对照组、模型组和... 详细信息

背景:糖尿病肾病是引起终末期肾病的重要原因,其中肠道屏障损伤在糖尿病肾病的发生发展中起到了重要作用。目的:观察人脐带间充质干细胞对糖尿病肾病大鼠肠道屏障的保护作用。方法:30只8周龄雄性SD大鼠随机分配至健康对照组、模型组和人脐带间充质干细胞组,每组10只。人脐带间充质干细胞组大鼠在糖尿病肾病成模后经尾静脉注射1×106个人脐带间充质干细胞,每周1次,连续4周,健康对照组和模型组大鼠在相同时间注射等体积PBS。末次注射后1周,光镜下观察肾脏和结肠组织形态学改变情况,免疫组化法检测大鼠结肠组织中ZO-1和Occludin的表达;ELISA法检测大鼠血清D-乳酸和脂多糖水平。此外,还利用活体成像系统观察DiR染料标记的人脐带间充质干细胞在大鼠体内的示踪分布,以及应用免疫组化法检测结肠组织中人源性间充质干细胞表面标志抗原CD44和CD90的表达。结果与结论:①与模型组比较,人脐带间充质干细胞移植显著抑制了糖尿病肾病大鼠尿素氮、血肌酐、24 h尿蛋白水平和尿白蛋白/肌酐比值的增加(均P<0.05);②在糖尿病肾病大鼠结肠中发现了人源间充质干细胞表面标志物CD44和CD90的表达;③与健康对照组相比,模型组大鼠结肠组织中紧密连接蛋白Occludin与ZO-1蛋白表达水平显著减少,而人脐带间充质干细胞治疗后显著提高了Occludin和ZO-1的表达;④与模型组比较,人脐带间充质干细胞移植后显著降低了糖尿病肾病大鼠血清D-乳酸和脂多糖水平;⑤结果提示,人脐带间充质干细胞可能通过增强糖尿病肾病大鼠肠道紧密连接蛋白的表达来保护肠道屏障功能。

关键词：人脐带间充质干细胞糖尿病肾病肠道屏障 ZO-1 Occludin