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BP网络预测H_2在煤液化油混合组分中的溶解度
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作者 罗化峰 《洁净煤技术》 CAS 2016年第4期117-120,131,共5页
为满足煤制油工业化过程中设计和操作需要,以H_2在神华煤液化油模型组分混合溶剂中实测溶解度为基础,考察利用人工神经网络法预测H_2在该系统中溶解度的能力。结果表明,神经网络的计算精度随着循环次数的增加而提高;对于不同种类的混合... 为满足煤制油工业化过程中设计和操作需要,以H_2在神华煤液化油模型组分混合溶剂中实测溶解度为基础,考察利用人工神经网络法预测H_2在该系统中溶解度的能力。结果表明,神经网络的计算精度随着循环次数的增加而提高;对于不同种类的混合溶剂,随着隐藏层个数的增加,计算值与试验值之间的相对误差呈现逐渐减小的趋势,从减小计算量的角度考虑,选定为4个隐藏层;3-4-1网络结构对于H_2在不同混合溶剂中溶解度的计算值与试验值最大相对误差为4.48%,这表明该模型能够满足H_2在该系统中溶解度的预测需要。 展开更多
关键词 溶解度 相平衡 人工神经网络 液化油模型组分混合溶剂
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组分液化对2A12铝合金回填式搅拌摩擦点焊接头力学性能的影响
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作者 赵宇佳 赵运强 +1 位作者 董春林 邓军 《热加工工艺》 北大核心 2023年第5期119-123,共5页
采用回填式搅拌摩擦点焊焊接方法对2 mm厚2A12铝合金进行焊接,并基于三维热流耦合有限元方法对焊接温度场和热循环进行数值模拟。结果表明,随着焊接转速增大,焊接峰值温度与高温停留时间增加,当焊接转速高于2000 r/min时,接头搅拌区发... 采用回填式搅拌摩擦点焊焊接方法对2 mm厚2A12铝合金进行焊接,并基于三维热流耦合有限元方法对焊接温度场和热循环进行数值模拟。结果表明,随着焊接转速增大,焊接峰值温度与高温停留时间增加,当焊接转速高于2000 r/min时,接头搅拌区发生组分液化现象,形成Cu、Mg元素富集的共晶组织,在接头横截面表现为"U"形线特征。当焊接转速为2000、2500 r/min时,在拉伸载荷作用下,裂纹优先在组分液化区域发生萌生并扩展,焊接接头的拉剪载荷分别为7.6、7.8 kN。当焊接转速为1500 r/min时,组分液化现象得到抑制,接头拉剪载荷提高至8.0 kN。 展开更多
关键词 回填式搅拌摩擦点焊 “U”形线 组分液化 共晶组织
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GH150合金焊接热影响区液化与液化裂纹 被引量:4
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作者 应慧筠 施成根 +3 位作者 郝传勇 于尔靖 秦旭东 张琪 《金属学报》 SCIE EI CAS CSCD 北大核心 1997年第9期995-1001,共7页
采用可变拘束试验、热塑性试验、差热分析、光镜与扫描电镜观察,研究了GH150合金焊接热影响区液化及液化裂纹形成机制加热过程中温度高于1250℃的热影响区由于γ/(Nb,Ti)C共晶产生液化,在温度达到1353℃(固相约至1375℃(液相线... 采用可变拘束试验、热塑性试验、差热分析、光镜与扫描电镜观察,研究了GH150合金焊接热影响区液化及液化裂纹形成机制加热过程中温度高于1250℃的热影响区由于γ/(Nb,Ti)C共晶产生液化,在温度达到1353℃(固相约至1375℃(液相线)的近维区,晶内出现大量液化点冷却过程中温度在1273和1200℃时形成γ/(Nb,Ti)C共晶和γ/Laves相共晶.(Nb,Ti)C组分液化及形成γ/Laves相共晶是GH150合金液化裂纹形成的主要冶金因素. 展开更多
关键词 组分液化 液化裂纹 高温合金
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膏体充填采煤用外加剂各组分作用探讨 被引量:4
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作者 李秀峰 陈印川 +1 位作者 邸文平 郑现军 《河北化工》 2011年第1期48-50,共3页
探讨了膏体充填采煤用外加剂中的流化组分、引气组分、保坍组分、早强组分的作用和作用机理,指出充填膏体中加入上述4种组分可以保证充填膏体具有优异的保水性能,保持良好的泵送性能,并能降低堵管风险。
关键词 膏体充填 采煤 外加剂 液化组分 引气组分 保坍组分 早强组分
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新建0.05 Mt/a异丁烷反异构装置的运行标定
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作者 张海龙 魏文 +2 位作者 卢喜洋 代恩东 李有坤 《石化技术与应用》 CAS 2024年第6期465-468,共4页
介绍了浙江石油化工有限公司采用美国UOP公司开发的Butamer工艺的C4反异构化技术新建的0.05 Mt/a异丁烷反异构装置,并总结了其在100%和110%设计负荷工况(以下分别简称为工况1#、工况2#)下的运行及标定情况。结果表明:在异丁烷原料性质... 介绍了浙江石油化工有限公司采用美国UOP公司开发的Butamer工艺的C4反异构化技术新建的0.05 Mt/a异丁烷反异构装置,并总结了其在100%和110%设计负荷工况(以下分别简称为工况1#、工况2#)下的运行及标定情况。结果表明:在异丁烷原料性质相近的前提下,在上述2种标定运行工况下,不仅前、后置异丁烷反应器入口温度均低于相应的设计值,而且该装置的正丁烷终产品收率(≥94.67%)和产品中的正丁烷体积分数(≥88.93%)均高于相应的设计值,异丁烷及C_(≥5)组分体积分数、含硫量、总含氯量等均低于相应的设计值;在工况1#、工况2#下的综合能耗较设计值分别降低了660.40,888.95 MJ/t。 展开更多
关键词 异丁烷 反异构化 正丁烷 液化气的C4组分 高附加值利用 收率 能耗
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新型超超临界S31035锅炉用钢焊接试验
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作者 杨顺田 蔡云松 姚军 《焊接》 2018年第2期26-30,共5页
针对700℃先进超超临界锅炉开发的310系列新型奥氏体耐热钢成分特点,分析了原材料的焊接性,结合备选焊材性能对比完成了焊材选型及焊接工艺方案,开展了小口径管TIG焊接工艺试验;对焊接接头进行了室温力学性能及高温持久性能测试,并分析... 针对700℃先进超超临界锅炉开发的310系列新型奥氏体耐热钢成分特点,分析了原材料的焊接性,结合备选焊材性能对比完成了焊材选型及焊接工艺方案,开展了小口径管TIG焊接工艺试验;对焊接接头进行了室温力学性能及高温持久性能测试,并分析了接头组织特征。试验结果表明,S31035锅炉用钢具有良好的焊接性,采用高匹配焊接材料可获得良好的接头性能及合格的显微组织。 展开更多
关键词 31035锅炉用钢 工艺试验 高匹配 持久性能 组分液化
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Protection of Veratrum nigrum L.var.ussuriense Nakai alkaloids against ischemia-reperfusion injury of the rat liver 被引量:5
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作者 Zhen-Zhen Wang Wei-Jie Zhao +7 位作者 Xue-Song Zhang Xiao-Feng Tian Yu-Zhu Wang Feng Zhang Jin-Chan Yuan Guo-Zhu Han Ke-Xin Liu Ji-Hong Yao 《World Journal of Gastroenterology》 SCIE CAS CSCD 2007年第4期564-571,共8页
AIM: TO investigate the protective effects and possible mechanisms of Veratrum nigrum L. var. ussuriense Nakai alkaloids (VnA) on hepatic ischemia/reperfusion (I/R) injury in rats. METHODS: Forty male Wistar rat... AIM: TO investigate the protective effects and possible mechanisms of Veratrum nigrum L. var. ussuriense Nakai alkaloids (VnA) on hepatic ischemia/reperfusion (I/R) injury in rats. METHODS: Forty male Wistar rats were randomly divided into four experimental groups (n = 10 in each): (A) Control group (the sham operation group); (8) I/R group (pretreated with normal saline); (C) Small-dose (10 μg/kg) VnA pretreatment group; (D) Large-dose (20 μg/kg) VnA pretreatment group. Hepatic ischemia/ reperfusion (Hepatic I/R) was induced by occlusion of the portal vein and the hepatic artery for 90 min, followed by reperfusion for 240 min. The pretreatment groups were administered with VnA intraperitoneally, 30 min before surgery, while the control group and I/R group were given equal volumes of normal saline. Superoxide dismutase (SOD) activity, myeloperoxidase (MPO) activity and nitric oxide (NO) content in the liver tissue at the end of reperfusion were determined and liver function was measured. The expression of intercellular adhesion molecule-1 (ICAM-1) and E-selectin (ES) were detected by immunohistochemical examinations and Western blot analyses. RESULTS: The results showed that hepatic I/R elicited a significant increase in the plasma levels of alanine aminotransferase (ALT: 74.53 ± 2.58 IU/L vs 1512.54 ± 200.76 IU/L, P 〈 0.01) and lactic dehydrogenase (LDH: 473.48 ± 52.17 IU/L vs 5821.53 ± 163.69 IU/L, P 〈 0.01), as well as the levels of MPO (1.97 ± 0.11 U/g vs 2.57 ± 0.13 U/g, P 〈 0.01) and NO (69.37 ± 1.52 μmol/g protein vs 78.39 ± 2.28 μmol/g protein, P 〈 0.01) in the liver tissue, all of which were reduced by pretreatment with VnA, respectively (ALT: 1512.54 ± 200.76 IU/L vs 977.93 ± 89.62 IU/L, 909.81 ± 132.76 IU/L, P 〈 0.01, P 〈 0.01; LDH: 5821.53 ± 163.69 IU/L vs 3015.44 ± 253.01 IU/L, 2448.75 ± 169.4 IU/L, P 〈 0.01, P 〈 0.01; MPO: 2.57 ± 0.13 U/g vs 2.13 ± 0.13 U/g, 2.07 ± 0.05 U/g, P 〈 0.01, P 〈 0.01; NO: 78.39 ± 2.28 μmol/g protein vs 71.11 ± 1.73 μmol/g protein, 68.58 ± 1.95 μmol/g protein, P 〈 0.05, P 〈 0.01). The activity of SOD (361.75 ± 16.22 U/rag protein vs 263.19 ± 12.10 U/rag protein, P 〈 0.01) in the liver tissue was decreased after I/R, which was enhanced by VnA pretreatment (263.19 ± 12.10 U/rag protein vs 299.40 ± 10.80 U/rag protein, 302.09 + 14.80 U/rag protein, P 〈 0.05, P 〈 0.05). Simultaneously, the histological evidence of liver hemorrhage, polymorphonuclear neutrophil infiltration and the overexpression of ICAM-1 and E-selectin in the liver tissue were observed, all of which were attenuated in the VnA pretreated groups. CONCLUSION: The results demonstrate that VnA pretreatment exerts significant protection against hepatic I/R injury in rats. The protective effects are possibly associated with enhancement of antioxidant capacity, reduction of inflammatory responses and suppressed expression of ICAM-1 and E-selectin. 展开更多
关键词 Veratrum nigrum L.var. ussuriense Nakaialkaloids Hepatic Ischemia/Reperfusion Injury Intracellular adhesion molecule-i E-SELECTIN
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Effect of ECAP process on liquid distribution of AZ80M alloy during semi-solid isothermal heat treatment 被引量:8
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作者 Ling-ling FAN Ming-yang ZHOU +2 位作者 Yang-yang GUO Yu-wen-xi ZHANG Gao-feng QUAN 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2021年第6期1599-1611,共13页
Two kinds of semi-solid samples of AZ80−0.2Y−0.15Ca(wt.%)(AZ80M)magnesium alloy were prepared by semi-solid isothermal heat treatment of materials with and without equal channel angular pressing(ECAP)process.The micro... Two kinds of semi-solid samples of AZ80−0.2Y−0.15Ca(wt.%)(AZ80M)magnesium alloy were prepared by semi-solid isothermal heat treatment of materials with and without equal channel angular pressing(ECAP)process.The microstructures of initial and semi-solid treated samples were compared and analyzed.The results showed a significant difference in the liquid phase distribution between three-pass ECAP processed(3P)and as-received samples during the isothermal heating process.The semi-solid 3P sample showed a more uniform liquid distribution due to its smaller dihedral angle.Besides,the coarsening processes of solid grains of as-received and 3P samples were dominated by the coalescence and Ostwald ripening mechanism,respectively.The difference of coarsening processes was mainly related to the proportion of the high-angle grain boundaries in materials,which further affected the evolution behavior of the liquid pools. 展开更多
关键词 AZ80M equal channel angular pressing semi-solid microstructure liquid phase distribution coarsening mechanism
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FB2马氏体耐热钢中Laves相在焊接过程中演化行为的研究 被引量:3
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作者 李克俭 蔡志鹏 +1 位作者 李轶非 潘际銮 《金属学报》 SCIE EI CAS CSCD 北大核心 2016年第6期641-648,共8页
采用热模拟的方法研究了FB2钢(一种新型9%Cr马氏体耐热钢)中Laves相在焊接热循环中的演化行为.首先借助SEM观察到存在于原始供货状态下的FB2钢中尺寸在微米级别的Laves相颗粒;进一步的分析表明,这些Laves相的出现是由铸造过程中的枝晶... 采用热模拟的方法研究了FB2钢(一种新型9%Cr马氏体耐热钢)中Laves相在焊接热循环中的演化行为.首先借助SEM观察到存在于原始供货状态下的FB2钢中尺寸在微米级别的Laves相颗粒;进一步的分析表明,这些Laves相的出现是由铸造过程中的枝晶偏析导致的.焊接热模拟实验结果表明,在加热过程中,Laves相与基体γ-Fe发生共晶反应导致的组分液化会给FB2钢热影响区带来热裂倾向;在冷却后的样品中发现了一些网状的共晶组织,利用SEM/EDS和TEM分别得到了该共晶组织的成分信息和结构信息,确定该共晶组织的2个组分为X相和γ-Fe.在此基础之上,较为详细地分析了不同峰值温度热模拟后样品中共晶组织的形成过程,解释了共晶组织不同形貌的产生原因. 展开更多
关键词 FB2钢 LAVES相 组分液化 x相 热裂倾向 焊接
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Role of long non-coding RNAs in normal and malignant hematopoiesis 被引量:1
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作者 WEI PanPan HAN BoWei CHEN YueQin 《Science China(Life Sciences)》 SCIE CAS 2013年第10期867-875,共9页
Long non-coding RNAs(lncRNAs)are defined as a class of nonprotein-coding transcripts greater than 200 nucleotides in length,which have diverse functions in development and diseases including hematopoiesis.Recent advan... Long non-coding RNAs(lncRNAs)are defined as a class of nonprotein-coding transcripts greater than 200 nucleotides in length,which have diverse functions in development and diseases including hematopoiesis.Recent advances have revealed that lncRNAs regulate hematopoietic development at almost every stage,including differentiation of the myelocyte,lymphocyte,and erythrocyte.Abnormal regulation of the lncRNAs may block aspects of blood development,which can lead to different types of hematopoietic disorders.These findings highlight the role of lncRNAs as potential therapeutic tools in malignant hematopoiesis.In this review,we summarize recent progress in the study of functional lncRNAs associated with blood development,as well as dysregulated lncRNAs involved in diverse blood diseases by interacting with crucial susceptibility genes in different pathways.In addition,we discuss genome-wide studies on lncRNAs,which are helpful for genome screening and in-depth functional study of lncRNAs associated with blood development and disease. 展开更多
关键词 long non-coding RNA (IncRNA) HEMATOPOIESIS blood disease susceptibility gene
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