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ODHE的世界展望与现代课题
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作者 王淑荣 丛培莲 《黑龙江高教研究》 CSSCI 北大核心 2008年第5期52-54,共3页
ODHE的教育模式,近年来成为世界各国的教育新宠,它以先进的教学手段、灵活多样的教学方式,为没有机会或没有能力进入正规大学的学习者,提供了最佳的教育环境和教育条件,成为世界各国培养技能型人才最主要的教育手段,亚洲各国也同样享受... ODHE的教育模式,近年来成为世界各国的教育新宠,它以先进的教学手段、灵活多样的教学方式,为没有机会或没有能力进入正规大学的学习者,提供了最佳的教育环境和教育条件,成为世界各国培养技能型人才最主要的教育手段,亚洲各国也同样享受着ODHE带来的利益,不过也面临着新的课题。 展开更多
关键词 odhe INTEMET 媒体技术
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Plasma treated M1 MoVNbTeO_(x)-CeO_(2) composite catalyst for improved performance of oxidative dehydrogenation of ethane
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作者 Shuairen Qian Yuxin Chen +1 位作者 Binhang Yan Yi Cheng 《Green Energy & Environment》 SCIE EI CAS CSCD 2023年第3期904-914,共11页
High activity and productivity of MoVNbTeO_(x) catalyst are challenging tasks in oxidative dehydrogenation of ethane(ODHE)for industrial application.In this work,phase-pure M1 with 30 wt%CeO_(2) composite catalyst was... High activity and productivity of MoVNbTeO_(x) catalyst are challenging tasks in oxidative dehydrogenation of ethane(ODHE)for industrial application.In this work,phase-pure M1 with 30 wt%CeO_(2) composite catalyst was treated by oxygen plasma to further enhance catalyst performance.The results show that the oxygen vacancies generated by the solid-state redox reaction between M1 and CeO_(2) capture active oxygen species in gas and transform V^(4+)to V^(5+)without damage to M1 structure.The space-time yield of ethylene of the plasma-treated catalyst was significantly increased,in which the catalyst shows an enhancement near~100% than that of phase-pure M1 at 400℃ for ODHE process.Plasma treatment for catalysts demonstrates an effective way to convert electrical energy into chemical energy in catalyst materials.Energy conversion is achieved by using the catalyst as a medium. 展开更多
关键词 Oxidative dehydrogenation of ethane(odhe) MoVNbTeO_(x) Composite catalyst Oxygen plasma Energy conversion
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氧化镍中非化学计量氧在乙烷氧化脱氢中的作用 被引量:26
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作者 陈铜 李文钊 于春英 《催化学报》 SCIE CAS CSCD 北大核心 1998年第1期37-41,共5页
以纯NiO为模型催化剂考察了乙烷氧化脱氢(ODHE)性能,发现非化学计量氧的存在与反应的活性及选择性密切相关.TGA研究结果表明,500℃制备的样品具有x≈6%的非化学计量氧.H2TPR结果表明,非化学计量氧与晶格氧... 以纯NiO为模型催化剂考察了乙烷氧化脱氢(ODHE)性能,发现非化学计量氧的存在与反应的活性及选择性密切相关.TGA研究结果表明,500℃制备的样品具有x≈6%的非化学计量氧.H2TPR结果表明,非化学计量氧与晶格氧的可还原性明显不同;O2TPDMS又把非化学计量氧区分为两个氧物种,O-2和O-(或O2-2).脉冲试验结果表明,非化学计量氧对ODHE制乙烯是选择性反应的活性氧物种,晶格氧是完全氧化反应的活性氧物种.一旦催化剂中非化学计量氧耗尽并动用晶格氧时,催化剂便有Ni0生成,表现出自催化性能,使反应活性迅速提高,但产物均为CO2,CO,CH4等完全燃烧或裂解产物.为保持有较高的乙烯收率,反应处于稳态时Ni必须处于高价态.电导测定结果表明,优良的ODHE催化剂应有P型半导性. 展开更多
关键词 氧化镍 非化学计量氧 乙烷 氧化脱氢 odhe
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焦钒酸镍的X射线光电子能谱及其氧化脱氢催化性能研究 被引量:2
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作者 徐爱菊 照日格图 +1 位作者 林勤 刘莲云 《功能材料》 EI CAS CSCD 北大核心 2007年第9期1489-1491,共3页
采用微波草酸盐共沉淀法制备了焦钒酸镍Ni2V2O7催化剂,并用XRD、BET、H2-TPR、XPS、TEM和电导等技术表征。研究了Ni2V2O7催化剂的丙烷氧化脱氢(ODH)制丙烯催化性能与其表面物种的关系。TPR和XPS实验结果显示p型半导体焦钒酸镍Ni2V2O7催... 采用微波草酸盐共沉淀法制备了焦钒酸镍Ni2V2O7催化剂,并用XRD、BET、H2-TPR、XPS、TEM和电导等技术表征。研究了Ni2V2O7催化剂的丙烷氧化脱氢(ODH)制丙烯催化性能与其表面物种的关系。TPR和XPS实验结果显示p型半导体焦钒酸镍Ni2V2O7催化剂中,晶格氧可以较容易转换成未完全还原氧,使催化剂内各种价态的钒之间易于进行氧化还原反应并形成氧缺位,从而催化剂的表面含有较多未充分还原氧物种O-和V4+物种。从而使其具有较高的丙烯选择性。 展开更多
关键词 Ni2V2O7 XPS H2-TPR 氧化脱氢(ODH) P型半导体
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Ni-V-O催化剂的合成、表征及其催化性能 被引量:1
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作者 徐爱菊 林勤 +1 位作者 照日格图 贾美林 《高等学校化学学报》 SCIE EI CAS CSCD 北大核心 2008年第2期341-345,共5页
制备了Ni3V2O8,Ni2V2O7,NiV2O6催化剂,进行了XRD,BET,H2-TPR,XPS和电导等表征,并测试了这三种结构催化剂对丙烷氧化脱氢制丙烯反应的催化性能,分析了影响催化性能的因素.实验结果表明,当丙烷的转化率为10%时,在p-型半导体Ni3V2O8和Ni2V... 制备了Ni3V2O8,Ni2V2O7,NiV2O6催化剂,进行了XRD,BET,H2-TPR,XPS和电导等表征,并测试了这三种结构催化剂对丙烷氧化脱氢制丙烯反应的催化性能,分析了影响催化性能的因素.实验结果表明,当丙烷的转化率为10%时,在p-型半导体Ni3V2O8和Ni2V2O7催化剂上丙烯的选择性为69.13%和70.21%,而在n-型半导体NiV2O6上,丙烯的选择性为64.41%,表明p-型半导体Ni3V2O8和Ni2V2O7的催化性能优于n-型半导体NiV2O6的催化性能.XPS实验结果表明,这可能与p-型半导体正钒酸镍(Ni3V2O8)和焦钒酸镍(Ni2V2O7)催化剂表面含较多O-氧物种和V4+有关. 展开更多
关键词 Ni-V-O催化剂 氧化脱氢(ODH) 半导体 氧物种
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FTIR和XPS光谱分析Co-V-O催化剂的丙烷氧化脱氢活性氧物种
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作者 徐爱菊 林勤 +2 位作者 照日格图 贾美林 刘莲云 《光谱学与光谱分析》 SCIE EI CAS CSCD 北大核心 2009年第2期346-350,共5页
制备了正钒酸钴Co3V2O8,焦钒酸钴Co2V2O7和偏钒酸钴CoV2O6三种催化剂,进行了XRD,TEM,BET,FTIR,XPS,H2-TPR和电导等表征,并测试了他们的丙烷氧化脱氢(ODH)制丙烯催化性能。对各催化剂的FTIR主要吸收峰做了经验归属,并对其O(1s)XPS谱... 制备了正钒酸钴Co3V2O8,焦钒酸钴Co2V2O7和偏钒酸钴CoV2O6三种催化剂,进行了XRD,TEM,BET,FTIR,XPS,H2-TPR和电导等表征,并测试了他们的丙烷氧化脱氢(ODH)制丙烯催化性能。对各催化剂的FTIR主要吸收峰做了经验归属,并对其O(1s)XPS谱进行了分峰拟合,计算了催化剂表面不同氧物种的含量。制得的催化剂晶粒均匀,平均粒径为20-30 nm,Co3V2O8和Co2V2O7具有p-型半导体性质,CoV2O6表现n-型半导体性质。p-型半导体Co3V2O8和Co2V2O7的丙烷ODH催化性能优于n-型半导体CoV2O6,当丙烷的转化率在10%时,在Co3V2O8,Co2V2O7,CoV2O6催化剂上丙烯选择性分别为48.12%,47.82%,35.24%。FTIR,XPS,H2-TPR和电导的研究结果表明,正、焦钒酸钴催化剂内各种价态钒之间易于进行氧化还原反应和形成氧缺位,钴含量的增加有利于丙烷转化的未充分还原的氧物种O2^-,O2^2-,O^-等增加,可以判断未充分还原的氧物种Oδ-(0〈δ〈2)是丙烷ODH活性氧物种。 展开更多
关键词 Co—V—O催化剂 氧化脱氢(ODH) 氧物种 XPS 半导体
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基于改进SIFT的离线签名鉴别方法 被引量:4
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作者 丁一 詹恩奇 +1 位作者 郑建彬 汪阳 《计算机应用研究》 CSCD 北大核心 2017年第11期3451-3454,3462,共5页
针对高质量模仿签名和签名图像的尺度变化对鉴别效果影响较大的问题,提出了一种基于改进SIFT的离线签名鉴别方法。该方法首先改进尺度空间的建立,减少尺度空间的层数和组数,然后检测签名图像的SIFT特征点和提取特征描述子,根据特征描述... 针对高质量模仿签名和签名图像的尺度变化对鉴别效果影响较大的问题,提出了一种基于改进SIFT的离线签名鉴别方法。该方法首先改进尺度空间的建立,减少尺度空间的层数和组数,然后检测签名图像的SIFT特征点和提取特征描述子,根据特征描述子间的欧氏距离进行匹配,通过邻近距离之比和特征点角度差筛选匹配对,并对匹配对特征点的角度差进行直方图统计构成ODH(orientation difference histogram)特征向量。最终根据匹配对的数量和ODH特征向量的相似度完成鉴别工作。该方法在本地数据库上的等误率为6.7%,在4NSig Comp2010公共数据库上的等误率为20%。实验结果表明,该方法与现有方法相比有效地提高了鉴别正确率。 展开更多
关键词 离线签名鉴别 尺度不变特征变换 尺度空间 匹配对筛选 ODH特征向量
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Oxidative dehydrogenation of propane under steady-state and transient regimes over alumina-supported catalysts prepared from mixed V_2W_4O_(19)^(4-) hexametalate precursors
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作者 Sébastien Paul Elise Berrier +1 位作者 Marcia Cristina Kaezer Frana Jean-Guillaume Eon 《Journal of Natural Gas Chemistry》 CAS CSCD 2010年第2期123-133,共11页
An integrated approach combining the development of an innovative catalyst and the research of a set of adequate operating conditions for the propane oxidative dehydrogenation (ODH) is described.The experimental set... An integrated approach combining the development of an innovative catalyst and the research of a set of adequate operating conditions for the propane oxidative dehydrogenation (ODH) is described.The experimental set-up,specially designed for steady-state and transient studies is presented.The preparation method,the characterization and the performances in steady-state and transient regimes of catalysts based on V2W4O194-Lindqvist isopolyanion used as a precursor and supported on alumina are reported.The influence of the preparation method of the catalyst and the role of water in the feed gas are more particularly discussed. 展开更多
关键词 PROPANE oxidative dehydrogenation (ODH) transient regime pulsed reactor Lindqvist isopolyanion in-situ Raman
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DHODH tangoing with GPX4 on the ferroptotic stage 被引量:3
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作者 Fudi Wang Junxia Min 《Signal Transduction and Targeted Therapy》 SCIE CSCD 2021年第7期1948-1949,共2页
Ferroptosis,an iron-dependent form of regulated cell death,is prevented by activity of the glutathione-dependent phospholipid hydroperoxidase GPX4(Glutathione peroxidase 4)in the cytosol and mitochondria,and by the gl... Ferroptosis,an iron-dependent form of regulated cell death,is prevented by activity of the glutathione-dependent phospholipid hydroperoxidase GPX4(Glutathione peroxidase 4)in the cytosol and mitochondria,and by the glutathione-independent CoQ10 oxidoreductase FSP1 at the plasma membrane.In their recent paper published in Nature,Mao et al.report that DHODH(Dihydroorotate dehydrogenase)coordinates with GPX4 to block ferroptosis in the mitochondrial inner membrane by reducing ubiquinone to form ubiquinol in cancer cells,thus providing a novel targeted strategy for treating cancer. 展开更多
关键词 CoQ10 DEATH ODH
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Surface Top Graphology,Corrosion and Microhardness of Oxygen Diffusion Hardened Pure Titanium Alloy TA4 after Laser Surface Melting
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作者 Chen Changjun,Zhang Min,Su Yanzhan,Zhang Shichang,Zhou Jialin Key Laboratory for Ferrous Metallurgy and Resources Utilization of Ministry of Education,Laser Processing Research Center,College of Materials and Metallurgy,Wuhan University of Science& Technology,Wuhan 430081,China 《稀有金属材料与工程》 SCIE EI CAS CSCD 北大核心 2011年第S4期185-189,共5页
In the oxygen diffusion hardened condition,untreated and laser surface melted pure titanium alloy (TA4) by Nd:YAG pulsed laser,are hardened at temperatures of 650 to 700℃ with the end result being a passive,mechanica... In the oxygen diffusion hardened condition,untreated and laser surface melted pure titanium alloy (TA4) by Nd:YAG pulsed laser,are hardened at temperatures of 650 to 700℃ with the end result being a passive,mechanically stable,abrasion resistant oxide ceramic rutile surface layer.The thickness of this surface layer depends on the time,temperature,and the microstructure of the Ti substrate.This paper describes the results of x-ray diffraction analysis,scanning electron microscope (SEM),microhardness measurements,and corrosion resistance measurements of hardened pure and laser treated Ti substrate.The oxygen diffusion hardened titanium alloy after laser surface melted samples (L-TA4) had a more pronounced grain structure and significantly higher roughness values than the untreated pure TA4 (U-TA4)samples.The L-TA4 samples also exhibited at least equivalent corrosion behavior and a definite increase in surface hardness compared to the U-TA4 samples.The results of this work suggest that laser surface melting plays a key role for effective oxygen diffusion hardening at 650-700℃ for pure and laser treated pure Ti alloys. 展开更多
关键词 oxygen diffusion harden (ODH) titanium ALLOY laser SURFACE MELTING CORROSION
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Correction to: Novel and potent inhibitors targeting DHODH are broad-spectrum antivirals against RNA viruses including newly-emerged coronavirus SARS-CoV-2
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作者 Rui Xiong Leike Zhang +22 位作者 Shiliang Li Yuan Sun Minyi Ding Yong Wang Yongliang Zhao Yan Wu Weijuan Shang Xiaming Jiang Jiwei Shan Zihao Shen Yi Tong Liuxin Xu Yu Chen Yingle Liu Gang Zou Dimitri Lavillete Zhenjiang Zhao Rui Wang Lili Zhu Gengfu Xiao Ke Lan Honglin Li Ke Xu 《Protein & Cell》 SCIE CAS CSCD 2021年第1期76-80,共5页
Figure 1.Discovery of novel and potent DHODHi and their anti-influenza A virus activities.(A)The discovery and design of S312 and S416.The detailed descriptions of the discovery workflow are in Method.Binding analysis... Figure 1.Discovery of novel and potent DHODHi and their anti-influenza A virus activities.(A)The discovery and design of S312 and S416.The detailed descriptions of the discovery workflow are in Method.Binding analysis of S312(B)and S416(C).Thermodynamic analysis of the binding of S312 and S416 to DHODH was carried out at 25 C on a MicroCal iTC200 instrument.Kinetic analysis of the binding of S312 and S416 to DHODH was performed with a Biacore T200 instrument. 展开更多
关键词 FIGURE discovery ODH
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