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民族药珠芽艾麻化学成分研究 被引量:29
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作者 朱珠 马琳 +2 位作者 朱海燕 杨小生 郝小江 《中药材》 CAS CSCD 北大核心 2011年第2期223-225,共3页
目的:对荨麻科艾麻属珠芽艾麻药材进行化学成分研究。方法:经70%乙醇回流提取,通过硅胶柱层析等技术,进行分离纯化,结合理化性质及各种波谱数据分析鉴定其化学结构。结果:从珠芽艾麻的根中分离并鉴定了6个化合物,分别是:β-谷甾醇(1)、... 目的:对荨麻科艾麻属珠芽艾麻药材进行化学成分研究。方法:经70%乙醇回流提取,通过硅胶柱层析等技术,进行分离纯化,结合理化性质及各种波谱数据分析鉴定其化学结构。结果:从珠芽艾麻的根中分离并鉴定了6个化合物,分别是:β-谷甾醇(1)、β-胡萝卜苷(2)2、2,'-oxy-bis(1-phenylethanol)(3)、1-(2-phenylcarbonyloxy ac-etyl)benzene(4)、亚油酸甲酯(5)和14,-二苯基-14,-丁二酮(6)。结论:所有化合物均为首次从该植物中分离得到,其中化合物3和4为首次报道的天然产物。 展开更多
关键词 珠芽艾麻 化学成分 22 '-oxy-bis(1-phenylethanol) 1-(2-phenylcarbonyloxy acetyl)benzene
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锡石浮选中捕收剂和金属离子的作用 被引量:18
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作者 曾清华 赵宏 王淀佐 《有色金属》 CSCD 1998年第4期21-25,共5页
研究了烷基磺化琥珀酰胺酸盐捕收剂(Aerosol-22)对锡石的浮选性能,以及金属阳离子对锡石浮选的影响.结果表明,Aerosol-22对锡石具有捕收性强、选择性好的特点,尤其是在弱酸性介质中作用效果更佳;铅离子对锡石浮选具有一定的活... 研究了烷基磺化琥珀酰胺酸盐捕收剂(Aerosol-22)对锡石的浮选性能,以及金属阳离子对锡石浮选的影响.结果表明,Aerosol-22对锡石具有捕收性强、选择性好的特点,尤其是在弱酸性介质中作用效果更佳;铅离子对锡石浮选具有一定的活化作用,而其它金属离子具有很强的抑制作用.应用光电子能谱(XPS)研究了锡石-捕收剂和金属阳离子-锡石-捕收剂体系中各组分之间的相互作用.研究表明,Aerosol-22通过其羧酸基和磺酸基中的氧原子与锡石表面锡质点发生化学键合形成化学吸附;铅离子提高了锡石表面锡质点的活性,而铁离子与Aerosol-22之间形成了稳定的螯合物.从而降低了锡石的浮游性. 展开更多
关键词 锡石 浮选 选矿 金属离子 捕收剂
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高温过热器T91、T22管爆管分析 被引量:20
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作者 赵彦芬 张路 +1 位作者 王正品 刘江南 《热力发电》 CAS 北大核心 2004年第11期61-64,共4页
某电厂锅炉高温过热器T91、T2 2管在运行 2万h后多次发生爆管 ,通过对原始管、运行管、爆管的组织和性能检测表明 ,爆管是由于T2 2管长时处于超温运行 ,在蒸汽侧产生大量氧化层 ,而氧化层在起停时剥落并沉积在下弯头附近 ,从而使管内流... 某电厂锅炉高温过热器T91、T2 2管在运行 2万h后多次发生爆管 ,通过对原始管、运行管、爆管的组织和性能检测表明 ,爆管是由于T2 2管长时处于超温运行 ,在蒸汽侧产生大量氧化层 ,而氧化层在起停时剥落并沉积在下弯头附近 ,从而使管内流量降低 。 展开更多
关键词 锅炉 高温过热器 爆管 力学性能 金相组织 高温过热器 T91 T22
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Interleukin-22 ameliorates liver fibrogenesis by attenuating hepatic stellate cell activation and downregulating the levels of inflammatory cytokines 被引量:18
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作者 Dong-Hong Lu Xiao-Yun Guo +7 位作者 Shan-Yu Qin Wei Luo Xiao-Li Huang Mei Chen Jia-Xu Wang Shi-Jia Ma Xian-Wen Yang Hai-Xing Jiang 《World Journal of Gastroenterology》 SCIE CAS 2015年第5期1531-1545,共15页
AIM:To investigate the effect of interleukin(IL)-22 onhepatic fibrosis in mice and the possible mechanism involved.METHODS:Liver fibrosis was induced in male BALB/c mice by CCl4.Recombinant IL-22(rm IL-22) was adminis... AIM:To investigate the effect of interleukin(IL)-22 onhepatic fibrosis in mice and the possible mechanism involved.METHODS:Liver fibrosis was induced in male BALB/c mice by CCl4.Recombinant IL-22(rm IL-22) was administered intraperitoneally in CCl4-treated mice.Fibrosis was assessed by histology and Masson staining.The activation of hepatic stellate cells(HSCs) was investigated by analysis of α-smooth muscle actin expression.The frequencies of T helper(Th) 22 cells,Th17 cells and Th1 cells,the expression of inflammatory cytokines [IL-22,IL-17 A,interferon-γ(IFN-γ),tumor necrosis factor-α(TNF-α),IL-6,IL-1b] and transcription factors [aryl hydrocarbon receptor(AHR),RAR-related orphan receptor(RORγt),T-bet] m RNA in the liver were investigated.In addition,the plasma levels of IL-22,IL-17 A,IFN-γ,TNF-α,IL-6 and IL-1b were evaluated.RESULTS:Significant elevations in circulating Th22 cells,Th17 cells,Th1 cells,IL-22,IL-17 A,and IFN-γ were observed in the hepatic fibrosis group compared with the control group(P < 0.01).Treatment with rm IL-22 in mice with hepatic fibrosis ameliorated the severity of hepatic fibrosis,which was confirmed by lower hepatic fibrosis pathological scores(P < 0.01).Rm IL-22 decreased the frequencies of Th22 cells(6.71% ± 0.97% vs 8.09% ± 0.74%,P < 0.01),Th17 cells(4.34% ± 0.37% vs 5.71% ± 0.24%,P < 0.01),Th1 cells(3.09% ± 0.49% vs 4.91% ± 0.73%,P < 0.01),and the levels of IL-22(56.23 ± 3.08 vs 70.29 ± 3.01,P < 0.01),IL-17A(30.74 ± 2.77 vs 45.68 ± 2.71,P < 0.01),and IFN-γ(74.78 ± 2.61 vs 124.89 ± 2.82,P < 0.01).Down-regulation of IL-22,IL-17 A,IFN-γ,TNF-α,IL-6,IL-1b,AHR RORγt,and T-bet gene expression in the liver was observed in the rm IL-22 group(P < 0.01).CONCLUSION:The frequencies of Th22,Th17 andTh1 cells are elevated in hepatic fibrosis.Rm IL-22 can attenuate HSC activation and down-regulate the levels of inflammatory cytokines,thereby ameliorating liver fibrogenesis. 展开更多
关键词 T HELPER 22 CELLS T HELPER 17 CELLS T HELPER 1 cel
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锅炉末级过热器爆管原因分析及措施 被引量:15
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作者 肖国华 王春明 +2 位作者 田晓 李益民 杨百勋 《热力发电》 CAS 北大核心 2012年第3期78-82,共5页
通过宏观形貌、成分分析、低倍观察、金相组织、硬度检验、室温拉伸和冲击试验等对某电厂2×362MW机组锅炉末级过热器爆管原因进行了分析。结果表明,爆管I(材质T22)断裂与焊道设计不合理、母材管金相组织及力学性能不合格有关;爆管... 通过宏观形貌、成分分析、低倍观察、金相组织、硬度检验、室温拉伸和冲击试验等对某电厂2×362MW机组锅炉末级过热器爆管原因进行了分析。结果表明,爆管I(材质T22)断裂与焊道设计不合理、母材管金相组织及力学性能不合格有关;爆管II(材质T91)断裂系焊接工艺执行不当,焊缝熔合线处存在夹渣和焊缝硬度偏高所致。对此提出了顶棚穿墙管与密封板的角焊缝应尽量避开密封板对接焊缝,改进密封板与管的焊接结构,减小定位块厚度等建议。 展开更多
关键词 末级过热器 T91 T22 焊接 爆管 金相组织 拉伸试验 冲击试验
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抗生素除草剂M-22除草效果的初步评价 被引量:9
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作者 蒋细良 朱昌雄 +3 位作者 杨怀文 孙东园 李少杰 姬军红 《中国生物防治》 CSCD 北大核心 2001年第1期47-47,F003,共2页
关键词 M-22 抗生素除草剂 广谱性除草剂 除草效果
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核心种质的集成创新思考及D22的选育 被引量:14
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作者 张世英 郭宝贵 +9 位作者 刘彬 蒋金玲 肖殿军 何俊峰 于雪飞 马永艳 曲淑君 温义鹏 朱秀森 郑莹 《玉米科学》 CAS CSCD 北大核心 2015年第2期33-35,共3页
用核心种质掖478和铁7922组配成基础材料F2代与早熟种质6314为原始材料,连续自交多代,育成中熟、高配合力、抗病性强和综合农艺性状好的玉米自交系D22。用其组配的杂交种早熟、抗逆性强、适应性广,成为我国玉米育种中重要的中熟种质资... 用核心种质掖478和铁7922组配成基础材料F2代与早熟种质6314为原始材料,连续自交多代,育成中熟、高配合力、抗病性强和综合农艺性状好的玉米自交系D22。用其组配的杂交种早熟、抗逆性强、适应性广,成为我国玉米育种中重要的中熟种质资源之一。 展开更多
关键词 玉米 核心种质 自交系 D22
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Melatonin attenuates acute pancreatitis-associated lung injury in rats by modulating interleukin 22 被引量:12
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作者 Jia-Ping Huai Xue-Cheng Sun Meng-Jun Chen Yin Jin Xiao-Hua Ye Jian-Sheng Wu Zhi-Ming Huang 《World Journal of Gastroenterology》 SCIE CAS CSCD 2012年第36期5122-5128,共7页
AIM: To investigate whether therapeutic treatment with melatonin could protect rats against acute pan- creatitis and its associated lung injury. METHODS: Seventy-two male Sprague-Dawley rats were randomly divided in... AIM: To investigate whether therapeutic treatment with melatonin could protect rats against acute pan- creatitis and its associated lung injury. METHODS: Seventy-two male Sprague-Dawley rats were randomly divided into three groups: the sham op- eration (SO), severe acute pancreatitis (SAP), and mel- atonin treatment (MT) groups. Acute pancreatitis was induced by infusion of 1 mL/kg of sodium taurocholate (4% solution) into the biliopancreatic duct. Melatonin (50 mg/kg) was administered 30 min before pancre- atitis was induced, and the severity of pancreatic and pulmonary injuries was evaluated 1, 4 and 8 h after induction. Serum samples were collected to measure amylase activities, and lung tissues were removed to measure levels of mRNAs encoding interleukin 22 (IL-22) and T helper cell 22 (Th22), as well as levels of IL-22.ing IL-22 and Th22 were significantly higher (P 〈 0.001) in the MT group than in the SAP group (0.526 ± 0.143 vs 0.156 ± 0.027, respectively, here and throughout, after 1 h; 0.489 ± 0.150 vs 0.113 ± 0.014 after 4 h; 0.524 ± 0.168 vs 0.069 ± 0.013 after 8 h, 0.378 ± 0.134 vs 0.122 ± 0.015 after 1 h; 0.205 ± 0.041 vs 0.076 ± 0.019 after 4 h; 0.302 ± 0.108 vs 0.045 ± 0.013 after 8 h, respectively) and significantly lower (P 〈 0.001) in the SAP group than in the SO group (0.156 ± 0.027 vs 1.000 ± 0.010 after 1 h; 0.113 ± 0.014 vs 1.041 ± 0.235 after 4 h; 0.069 ± 0.013 vs 1.110 ± 0.213 after 8 h, 0.122 ± 0.015 vs 1.000 ± 0.188 after 1 h; 0.076 ± 0.019 vs 0.899 ± 0.125 after 4 h; 0.045 ± 0.013 vs 0.991 ± 0.222 after 8 h, respectively). The mean pathologi- cal scores for pancreatic tissues in the MT group were significantly higher (P 〈 0.01) than those for samples in the SO group (1.088 ± 0.187 vs 0.488 ± 0.183 after 1 h, 2.450 ± 0.212 vs 0.469 ± 0.242 after 4 h; 4.994 ± 0.184 vs 0.513 ± 0.210 after 8 h), but were significantly lower (P 〈 0.01) than those for samples in the SAP group at each time point 展开更多
关键词 Interleukin 22 MELATONIN Pancreatitis-associated lung injury Severe acute pancreatitis Thelper 22 cell
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岩筋菜的化学成分研究 被引量:12
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作者 丁立生 陈耀祖 吴凤锷 《中国中药杂志》 CAS CSCD 北大核心 1991年第5期289-290,共2页
从岩筋菜根部乙醇提取物的中性部分分离得到三个结晶,经光谱方法鉴定为金腰素乙,22,23-二氢波菜甾酮和波菜甾醇及22,23-二氢波菜甾醇的混合物。
关键词 岩筋菜 化学成分 金腰素乙
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Salvianolate increases heat shock protein expression in a cerebral ischemia-reperfusion injury model 被引量:12
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作者 Jinnan Zhang Wei Lu +3 位作者 Qiang Lei Xi Tao Hong You Pinghui Xie 《Neural Regeneration Research》 SCIE CAS CSCD 2013年第25期2327-2335,共9页
Stroke remains a worldwide health problem. Salvianolate exerts a protective effect in various mi- crocirculatory disturbance-related diseases, but studies of the mechanisms underlying its protective action have mainly... Stroke remains a worldwide health problem. Salvianolate exerts a protective effect in various mi- crocirculatory disturbance-related diseases, but studies of the mechanisms underlying its protective action have mainly focused on the myocardium, whereas little research has been carried out in brain tissue following ischemia-reperfusion. We assessed the neuroprotective effects of salvianolate in a rat model of cerebral ischemia-reperfusion injury induced using the suture method. At onset and 24 and 48 hours after reperfusion, rats were intraperitoneally injected with salvianolate (18 mg/kg) or saline. Neurological deficit scores at 72 hours showed that the neurological functions of rats that had received salvianolate were significantly better than those of the rats that had received saline. 2,3,5-Triphenyltetrazolium chloride was used to stain cerebral tissue to determine the extent of the infarct area. A significantly smaller infarct area and a significantly lower number of apoptotic cells were observed after treatment with salvianolate compared with the saline treatment. Expression of heat shock protein 22 and phosphorylated protein kinase B in ischemic brain tissue was significantly greater in rats treated with salvianolate compared with rats treated with saline. Our findings suggest that salvianolate provides neuroprotective effects against cerebral ischemia-reperfusion injury by upregulating heat shock protein 22 and phosphorylated protein kinase B expression. 展开更多
关键词 neural regeneration traditional Chinese medicine brain injury salvianolic acid B SALVIANOLATE heatshock protein 22 protein kinase B cerebral ischemia-reperfusion injury apoptosis NEUROPROTECTION NEUROREGENERATION
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HPLC法同时测定金针菇中麦角甾醇和22,23-二氢麦角甾醇的含量 被引量:11
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作者 易承学 童珊珊 +1 位作者 徐希明 余江南 《江苏大学学报(医学版)》 CAS 2014年第2期126-128,共3页
目的:建立高效液相色谱(high performance liquid chromatography,HPLC)法同时测定金针菇中麦角甾醇和22,23-二氢麦角甾醇含量。方法:采用Inertsil ODS-SP(250 mm×4.6 mm,5μm)色谱柱同时测定上述2种成分,流动相为甲醇,流速1.0 mL&... 目的:建立高效液相色谱(high performance liquid chromatography,HPLC)法同时测定金针菇中麦角甾醇和22,23-二氢麦角甾醇含量。方法:采用Inertsil ODS-SP(250 mm×4.6 mm,5μm)色谱柱同时测定上述2种成分,流动相为甲醇,流速1.0 mL·min-1,检测波长为282 nm,柱温25℃。结果:麦角甾醇和22,23-二氢麦角甾醇的进样量在0.025~1.5μg范围内呈良好线性关系(r=0.999 9);平均回收率(n=6)分别为104.6%[相对标准偏差(RSD)=0.89%],103.5%(RSD=3.34%)。结论:该方法简便,快速,准确,适用于测定金针菇中麦角甾醇和22,23-二氢麦角甾醇的含量。 展开更多
关键词 金针菇 麦角甾醇 22 23-二氢麦角甾醇 高效液相色谱法
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湖北枣阳郭家庙墓地曹门湾墓区(2014)M10、M13、M22发掘简报 被引量:10
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作者 张天宇 姜波 +18 位作者 刘小华 耿壮壮 李凯 邓蔚蓝 黄文广 王茂文 余乐 胡刚 余成龙 符德明 曾令斌 张丙舟 刘娜 陈丽莹 魏付丽 熊燕 余霜 凡国栋 方勤 《江汉考古》 CSSCI 北大核心 2016年第5期13-35,共23页
2014年10月至2015年1月,湖北省文物考古研究所、湖北荆州文物保护中心等单位组成联合考古队,对湖北枣阳郭家庙墓地曹门湾墓区进行了发掘,清理春秋早期墓葬二十五座、车坑一座、马坑二座、车马坑一座,通过发掘确认曹门湾墓区是春秋早期... 2014年10月至2015年1月,湖北省文物考古研究所、湖北荆州文物保护中心等单位组成联合考古队,对湖北枣阳郭家庙墓地曹门湾墓区进行了发掘,清理春秋早期墓葬二十五座、车坑一座、马坑二座、车马坑一座,通过发掘确认曹门湾墓区是春秋早期曾国墓地,其中,曹门湾M10、M13、M22保存完整,本简报将主要报道这三座墓葬的发掘情况。 展开更多
关键词 郭家庙 曹门湾 曾国 M10 M13 M22 春秋早期
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重症急性胰腺炎患者监护期间实施临床路径的效果 被引量:10
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作者 李建萍 叶文琴 +2 位作者 田梅梅 湛先保 张英英 《解放军护理杂志》 2012年第4期17-19,22,共4页
目的探讨重症急性胰腺炎(severe acute pancreatitis,SAP)患者监护期间实施临床路径(clinical pathway,CP)的效果。方法按随机数字表法将2006年11月至2009年2月第二军医大学长海医院消化内科收治的82例SAP患者分为对照组和观察组各41例... 目的探讨重症急性胰腺炎(severe acute pancreatitis,SAP)患者监护期间实施临床路径(clinical pathway,CP)的效果。方法按随机数字表法将2006年11月至2009年2月第二军医大学长海医院消化内科收治的82例SAP患者分为对照组和观察组各41例,对照组按SAP常规进行监护治疗,观察组实行临床路径管理,比较两组患者的治疗转归情况、住院时间、住院总费用以及患者对健康知识掌握程度和患者对医护人员满意度等。结果观察组患者肺部感染率明显低于对照组(P<0.05);观察组住院总费用明显低于对照组(P<0.05);观察组患者对医护人员的总体评价、疗效及疼痛、药物治疗等健康知识掌握程度均明显高于对照组(P<0.05)。结论 SAP监护期间的临床路径为患者的治疗护理提供了标准化模式,有利于提高医护工作质量,促进患者康复和提高患者的满意度。 展开更多
关键词 重症急性胰腺炎 监护期间 临床路径 管理 标准化模式
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Loss of heterozygosity on chromosome 22 in sporadic schwannoma and its relation to the proliferation of tumor cells 被引量:8
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作者 BIAN Liu-guan SUN Qing-fang +4 位作者 Tirakotai Wuttipong ZHAO Wei-guo SHEN Jian-kang LUO Qi-zhong Bertalanffy Helmut 《Chinese Medical Journal》 SCIE CAS CSCD 2005年第18期1517-1524,共8页
Background Schwannoma is the tumor arising mainly from the cranial and spinal nerves. Bilateral vestibular schwannoma is the hallmark of neurofibromatosis type 2 (NF2). The NF2 gene has been cloned with comprehensiv... Background Schwannoma is the tumor arising mainly from the cranial and spinal nerves. Bilateral vestibular schwannoma is the hallmark of neurofibromatosis type 2 (NF2). The NF2 gene has been cloned with comprehensive analysis of its mutations in schwannoma. However, most studies focused on vestibular schwannoma. There are differences in proliferation of tumor cell and uhrastructure between vestibular and spinal schwannomas. It is unknown whether genetic alterations in vestibular schwannoma are different from those in non-vestibular schwannoma. We analyzed the loss of heterozygosity (LOH) on chromosome 22 in patients with sporadic schwannoma including vestibular and spinal schwannomas and correlated this genetic alteration with tumor proliferation. Methods In 54 unrelated patients without clinical NF1 or NF2, 36 patients had sporadic vestibular schwannoma, and 18 dorsal spinal root schwannoma. Four highly polymorphic linkage to NF2 gene microsatellite DNA markers (D22S264, D22S268, D22S280, CRYB2) were used to analyze LOH. The proliferative index was evaluated by Ki-67 and proliferative cell nuclear antigen (PCNA) immunostaining. Student's t test was used to analyze the difference of the proliferative index between schwannoma with LOH and that without LOH. The difference of the frequency of LOH in vestibular and spinal schwannomas was investigated by the chi-square test. Results Twenty-three schwannomas (42. 6% , 23/54) showed allele loss. The frequency of LOH in vestibular schwannoma was significantly higher than that in spinal schwannoma ( X^2 = 5.14, P 〈 0.05 ). The proliferative index of schwannoma with LOH was significantly higher than that without LOH (tki-67 = 2. 97, P= 0. 0045 ; tPCNA =2.93, P =0. 0051). Conclusions LOH on chromosome 22 is a frequent there is a correlation between LOH on chromosome 22 event in the tumorigenesis of sporadic schwannoma. And, and proliferative activity in schwannoma. The frequency of LOH in vestibular schwannoma is significantly different from 展开更多
关键词 schwannomas·loss of heterozygosity·chromosome 22
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尿素级超低碳奥氏体不锈钢钢管的研制及应用 被引量:8
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作者 丁文炎 邵羽 +1 位作者 王建勇 黄伟 《钢管》 CAS 2013年第5期35-40,共6页
从材料冶炼方法、化学成分控制、热挤压制度、热处理制度、酸洗工艺、休氏试验等方面对尿素级超低碳奥氏体不锈钢钢管进行研究,在总结该类产品的技术要求、特点的基础上,进行试制。试制结果表明:所研制的尿素级25.22.2不锈钢钢管,其实... 从材料冶炼方法、化学成分控制、热挤压制度、热处理制度、酸洗工艺、休氏试验等方面对尿素级超低碳奥氏体不锈钢钢管进行研究,在总结该类产品的技术要求、特点的基础上,进行试制。试制结果表明:所研制的尿素级25.22.2不锈钢钢管,其实物质量和性能与国外进口材料相当,可应用于大型尿素装置的换热管和工艺管道,为实现尿素用钢的国产化创造了条件。 展开更多
关键词 尿素装置 奥氏体不锈钢 挤压管 尿素级25 22 2 超低碳 国产化
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Challenges of 22 nm and beyond CMOS technology 被引量:8
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作者 HUANG Ru WU HanMing +8 位作者 KANG JinFeng XIAO DeYuan SHI XueLong AN Xia TIAN Yu WANG RunSheng ZHANG LiangLiang ZHANG Xing WANG YangYuan 《Science in China(Series F)》 2009年第9期1491-1533,共43页
It is predicted that CMOS technology will probably enter into 22 nm node around 2012. Scaling of CMOS logic technology from 32 to 22 nm node meets more critical issues and needs some significant changes of the technol... It is predicted that CMOS technology will probably enter into 22 nm node around 2012. Scaling of CMOS logic technology from 32 to 22 nm node meets more critical issues and needs some significant changes of the technology, as well as integration of the advanced processes. This paper will review the key processing technologies which can be potentially integrated into 22 nm and beyond technology nodes, including double patterning technology with high NA water immersion lithography and EUV lithography, new device architectures, high K/metal gate (HK/MG) stack and integration technology, mobility enhancement technologies, source/drain engineering and advanced copper interconnect technology with ultra-low-k process. 展开更多
关键词 CMOS technology 22 nm technology node device architectures metal gate^high K dielectrics ultra low K dielectrics
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T22/TP310H异种钢焊接接头的显微组织分析 被引量:8
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作者 王德伟 胡从荣 +1 位作者 付志伟 陶锋 《热加工工艺》 CSCD 北大核心 2014年第15期47-49,53,共4页
采用手工钨极氩弧焊,选用ERNiCr-3镍基焊丝,对T22/TP310H异种钢进行焊接。焊后利用光学显微镜、扫描电镜、X射线衍射仪及能谱仪对焊接接头进行了分析研究。结果表明:焊缝组织主要为胞状树枝晶,焊缝金属的组成相主要有奥氏体基体γ相、Nb... 采用手工钨极氩弧焊,选用ERNiCr-3镍基焊丝,对T22/TP310H异种钢进行焊接。焊后利用光学显微镜、扫描电镜、X射线衍射仪及能谱仪对焊接接头进行了分析研究。结果表明:焊缝组织主要为胞状树枝晶,焊缝金属的组成相主要有奥氏体基体γ相、NbC和M23C6碳化物相。T22侧热影响区有任意分布的块状铁素体,也有呈条状聚合物的块状铁素体;TP310H侧HAZ中奥氏体晶粒粗化现象不明显。 展开更多
关键词 T22 TP310H 异种钢焊接 焊接接头 显微组织
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A DiGeorge Syndrome Case Report—Challenges of Diagnosis and Management
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作者 Dumitru Amoasii 《Open Journal of Internal Medicine》 2024年第3期278-286,共9页
Background: DiGeorge syndrome (also known as velo-cardio-facial syndrome) is a rare multisystem genetic disorder occurring in approximately 1 in 4000 to 1 in 6000 live births [1]. Although advances in genetic screenin... Background: DiGeorge syndrome (also known as velo-cardio-facial syndrome) is a rare multisystem genetic disorder occurring in approximately 1 in 4000 to 1 in 6000 live births [1]. Although advances in genetic screening have improved diagnosis in developed countries, the condition remains underdiagnosed in developing nations such as the Republic of Moldova, where access to genetic testing and family planning services is limited. Routine prenatal screening usually includes regular ultrasounds, monitoring of blood pressure, complete blood counts, coagulation studies, glucose, urine protein, and urine culture. Current ultrasound techniques have limitations in detecting this syndrome due to variability in interpretation, and genetic testing is often performed based on clinical discretion. The ultrasound could potentially point towards a genetic problem, as in DiGeorge, if multiple cardiac malformations are spotted in utero, but most cases such as this one are diagnosed after birth while being described as totally normal on prenatal ultrasound. Purpose: This study aims to highlight the diagnostic challenges and the need for comprehensive evaluation in identifying DiGeorge syndrome, emphasizing the importance of considering the syndrome as a whole rather than focusing on isolated organ system issues. Method: We present a case report of a 6-month-old girl who, after an uneventful pregnancy and normal prenatal ultrasound, presented with cardiac insufficiency. Following extensive investigations and multiple surgical interventions, DiGeorge syndrome was diagnosed at 9 months of age. Results: The patient’s diagnosis was delayed due to the lack of prenatal markers and the reliance on separate investigations of affected organ systems. Despite several interventions aimed at managing her symptoms, the final diagnosis was made after observing the association of multiple clinical features and conducting comprehensive genetic testing. Conclusions: This case underscores the importance of a holistic approach to diagnosis, which inv 展开更多
关键词 DIGEORGE Velo-Cardio-Facial TBX-1 Gene Chromosome 22 22q11.2 Deletion Septal Defect IMMUNODEFICIENCY Thymic Shadow Congenital Cardiac Abnormalities Prenatal Screening
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亚硒酸锰(Ⅲ)-叶绿酸钠的制备及其对小鼠的急性毒性和小鼠肝癌H_(22)的初步试验 被引量:6
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作者 李晓勇 陶海鹏 +1 位作者 俞华珊 王朝俊 《华西药学杂志》 CAS CSCD 北大核心 2000年第1期6-8,共3页
目的:制备亚硒酸锰()-叶绿酸钠,并测定其对小鼠的急性毒性及对小鼠肝癌H22的抑制情况。方法:以蚕沙提取叶绿素,由叶绿素制备脱镁叶绿酸,与锰络合后制得锰()叶绿酸,再以亚硒酸化合制得亚硒酸锰()-叶绿酸钠;测定亚硒酸锰()-叶绿酸钠的急... 目的:制备亚硒酸锰()-叶绿酸钠,并测定其对小鼠的急性毒性及对小鼠肝癌H22的抑制情况。方法:以蚕沙提取叶绿素,由叶绿素制备脱镁叶绿酸,与锰络合后制得锰()叶绿酸,再以亚硒酸化合制得亚硒酸锰()-叶绿酸钠;测定亚硒酸锰()-叶绿酸钠的急性毒性及对小鼠肝癌H22的抑制情况。结果:作者首次合成了亚硒酸锰()-叶绿酸钠。测得其LD50=1175mg·kg-1(95%的可信区间为851~1621mg·kg-1;其对小鼠肝癌H22的抑癌率为45~47%(灌胃剂量为500mg·kg-1)。结论:亚硒酸锰()-叶绿酸钠常温下性质稳定,毒性小,对小鼠肝癌H22有明显的抑制作用。 展开更多
关键词 亚硒酸 脱镁叶绿酸锰 叶绿酸 制备 肝癌
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长期服役后TP304H/T22型异种钢焊缝失效原因分析 被引量:7
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作者 范志东 张志博 +3 位作者 徐刚 马翼超 牛坤 唐文书 《热加工工艺》 北大核心 2019年第17期175-178,182,共5页
某电厂进口亚临界锅炉在检修中,发现高温过热器出口管段TP304H/T22型异种钢焊缝从内壁开裂。通过对失效异种钢管样的宏观形貌、规格尺寸、化学成分、显微硬度、显微组织等方面的分析,得出结论:裂纹从内壁的焊接内衬环与母材的未熔合位... 某电厂进口亚临界锅炉在检修中,发现高温过热器出口管段TP304H/T22型异种钢焊缝从内壁开裂。通过对失效异种钢管样的宏观形貌、规格尺寸、化学成分、显微硬度、显微组织等方面的分析,得出结论:裂纹从内壁的焊接内衬环与母材的未熔合位置起裂,并向焊缝内部扩展;焊缝及两侧母材的规格尺寸、化学成分、显微硬度和显微组织均符合要求;焊接衬环与母材的未熔合界面具有应力集中效应,是异种钢焊缝在设计寿命前开裂的主因。检测试验发现,射线检测和超声相控阵检测均无法有效检出此类裂纹。 展开更多
关键词 异种钢焊缝 失效分析 焊接衬环 T22 TP304H
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