检索结果-南通市图书馆

Synthesis of TiO_2/ZnSn(OH)_6 Hollow Nano-composite via a Simultaneous Crystallization-etching Route as Photocatalyst

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Structural Chemistry 2013年第12期32卷 1829-1834页

作者： YU Han li chang-rong CAO Zhou-Ming ZHANG Zi-Zhong College of Materials Science and Engineering Fuzhou University College of Chemistry and Chemical Engineering Fuzhou University

We report the synthesis of TiO2/ZnSn（OH）6 as a novel nano-composite material via a simultaneous crystallization-etching route with cubic nano-ZnSn（OH）6 and TiF4 as the precursors. The structure, composition and morphology of the composite were characterized by XRD, EDS, FETEM and FESEM, which showed the prepared TiO2/ZnSn（OH）6 had a unique morphology of hollow cubic nano-ZnSn（OH）6 attached with rutile TiO2 nanoparticles. The results of photocatalytic activity measurement indicated the photocatalytic activity of the prepared composite was better than that of nano-ZnSn（OH）6. This study may be helpful for the design and fabrication of functional comoosite materials.

关键词： ZnSn(OH)6 rutile TiO2 nano-composite photocatalysis

Construction of Prokaryotic Expression Vector of Mouse Nanog Gene and Its Expression

在线全文

学校读者我要写书评

暂无评论

Agricultural Sciences in China 2007年第4期6卷 487-492页

作者： li Jun Lü chang-rong DOU lin DOU Zhong-ying Shaanxi Center of National Stem Cell Engineering ＆ Technology Center Northwest A＆F University Yangling 712100 P.R.China

The aim of this study is to construct a prokaryotic expression vector of mouse Nanog gene and to express it in E. coli. A pair of primers was designed according to digestion sites in plasmid pGEX-KG and the Nanog gene sequence published by GenBank. The DNA fragment of 918 bp was amplified by polymerase chain reaction （PCR） from the pNA992 recombinant plasmid with Nanog gene, then cloned into pGEX-KG and transformed into the host E. coli strain TG Ⅰ. The sequence of the fragment was matched with the original sequence of pNA992. It indicated that fusion expression vector, pGEX-KG- Nanog, was constructed successfully. The pGEX-KG-Nanog plasmid was extracted from E. coli strain TG Ⅰ and was transformed into BL21（DE3） for expression. After induction by isopropyl-β-D-thiogalactoside （IPTG） at 37℃, the expression product of Nanog gene was identified by sodium dodecyl sulfate-polyacrylamide gel electrophoresis （SDS-PAGE）, and the expression condition was optimized. Nanog fusion protein was successfully expressed in the form of inclusion bodies. The molecular weight of the inclusion body was 63 kDa. Meanwhile, the optimum condition for the expression of Nanog fusion protein was induced with 0.8 mmol L^-1 IPTG for 5 h. The mouse Nanog gene was successfully expressed in E. coli, which laid a foundation for the purification of Nanog protein and for the preparation of polyclonal antibody.

关键词： Nanog gene prokaryotic expression glutathione-S-transferase (GST) fusion protein mouse

Electrochemical Catalytic Properties of Pt/FeSnO(OH)_5 towards Methanol Oxidation

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Structural Chemistry 2018年第10期37卷 1585-1595页

作者： ZHAN Xia-Dan ZHAN Ying-Xu DU chang-Chao li chang-rong YU Han liN Cong State Key Laboratory of Photocatalysis on Energy and Environment Key Laboratory of Eco-materials Advanced Technology (Fuzhou University)Fujian Province UniversityCollege of Materials Science and EngineeringFuzhou UniversityFuzhou 350108，China

The Pt/FeSnO（OH）_5 catalyst has been prepared by depositing Pt nanoparticles on the synthesized FeSnO（OH）_5 nanoboxes and demonstrates excellent performance towards methanol oxidation reaction（MOR） in direct methanol fuel cells（DMFCs）.The Pt/FeSnO（OH）_5 catalyst exhibits a higher mass activity（1182.35 mA/mgPt） compared with Pt/C（594.57 mA/mgPt） *** X-ray powder diffraction,field emission scanning electron microscope,field emission transmission electron microscopy,X-ray photoelectron spectroscopy and electrochemical experiments have been employed to explore the relationships between the crystal structure and electrochemical *** increased activity and resistance of CO poisoning for Pt/FeSnO（OH）_5 catalyst can be attributed to the strong interaction between the transition metal in the hydroxide and Pt and the bifunctional *** higher relative concentration of Pt^0 in Pt/FeSnO（OH）_5 also contributes to the MOR ***,the charge transfer resistance of Pt/FeSnO（OH）_5 is lower than that of Pt/***,Pt/FeSnO（OH）_5 has great application prospect as a high-performance electrocatalyst in DMFCs.

关键词： Pt/FeSnO(OH)5 direct methanol fuel cell metal-support interaction

在线全文

学校读者我要写书评

暂无评论

氧化铝/氧化镧X射线衍射及拉曼光谱研究

光谱学与光谱分析 2021年第8期41卷 2480-2483页

作者：王奕李长荣庄昌凌贵州大学材料与冶金学院贵州贵阳550025 贵州省冶金工程与过程节能重点实验室贵州贵阳550025

当钢中氧化铝夹杂物的尺寸过大、棱角分明,在线材拉拔为钢丝的过程中可视为主要的裂纹源,会严重影响钢材性能,细化或去除钢中夹杂物备受重视。由于钢中合金元素添加量相对于钢液较小,并在实验及分析的中间过程中存在误差,使用放大夹杂... 详细信息

当钢中氧化铝夹杂物的尺寸过大、棱角分明,在线材拉拔为钢丝的过程中可视为主要的裂纹源,会严重影响钢材性能,细化或去除钢中夹杂物备受重视。由于钢中合金元素添加量相对于钢液较小,并在实验及分析的中间过程中存在误差,使用放大夹杂物反应的思路,研究了在高温1600℃时,不同比例稀土氧化镧粉末和氧化铝粉末的添加量对夹杂物的物相变化、尺寸大小的影响。对高温箱式炉设定程序进行升温、保温、随炉冷却,使用X射线衍射仪、拉曼光谱仪测试结果分析了镧铝氧化物的具体变化过程。结果表明:随着La_(2)O_(3)添加量的不断增加,最先生成LaAl_(11)O_(18)相,其次为LaAl_(11)O_(18),LaAlO_(3)相,峰强减弱,半高宽增加,晶粒尺寸变小,随后LaAl_(11)O_(18)特征峰消失,只剩下LaAlO_(3)相,且并无新相生成。结合H-W平均晶粒尺寸数学模型计算R^(2)分别为0.99025,0.96259,0.9871和0.98976,且1^(^(#))样品到4^(#)样品晶粒尺寸分别为6.08,2.88,7.67和4.75μm,2^(^(#))样品晶粒尺寸最小,3^(#)样品晶粒尺寸最大,表明合适的氧化镧和氧化铝配比可以促进形核并缩小晶粒尺寸。通过拉曼光谱分析得出,随着Al_(2)O_(3)配比的减少,观察拉曼位移在4385 cm^(-1)处拉曼特征峰消失,结合XRD图谱可以判定该处为LaAl_(11)O_(18)相。3^(#)—4^(#)曲线在拉曼位移为3564~3642和4461~5554 cm^(-1)处出现拉曼特征峰,结合2^(#)曲线以及XRD图谱可知,生成新的LaAlO_(3)相,且3^(#)样品和4^(#)样品的不同配比对拉曼峰强无太大影响,也没有出现新的特征峰。通过放大钢中需要针对性研究的物质,分析了氧化镧粉末添加后对氧化铝粉末改性的演变过程。研究结果可对实际炼钢过程中解决氧化铝夹杂物改性的问题提供参考。

关键词：镧氧化物 XRD 拉曼光谱晶粒尺寸

在线全文

学校读者我要写书评

暂无评论

铜在富FeO熔渣中的氧化溶解行为

中国有色金属学报 2005年第5期15卷 813-816页

作者：李长荣洪新郑少波蒋国昌上海大学材料科学与工程学院上海200072

在1873K条件下对铜在富FeO熔渣中的氧化溶解行为进行了研究。结果表明铜氧化物在富FeO熔渣中以Cu2O的形式存在;熔渣中CaO的含量将对铜的氧化溶解产生影响,随着渣中CaO含量的增加,熔渣中的铜含量逐渐下降,但在不同温度下,这种影响的作用... 详细信息

在1873K条件下对铜在富FeO熔渣中的氧化溶解行为进行了研究。结果表明铜氧化物在富FeO熔渣中以Cu2O的形式存在;熔渣中CaO的含量将对铜的氧化溶解产生影响,随着渣中CaO含量的增加,熔渣中的铜含量逐渐下降,但在不同温度下,这种影响的作用各不相同;当温度较高时,渣中CaO含量对铜的氧化溶解影响较大,且随着温度的降低,其影响作用明显变缓;反应体系的氧分压对铜的氧化溶解影响较大,在熔渣中γ(CuO0.5)不变的情况下,铜氧化物的溶解与体系氧分压的四分之一次方之间呈正线性关系。

关键词：铜氧化物富FeO熔渣溶解行为

在线全文

学校读者我要写书评

暂无评论

GH674高温合金的热变形行为

金属热处理 2005年第8期30卷 5-7页

作者：李佃国尹法杰李长荣北京科技大学材料科学与工程学院北京100083 钢铁研究总院高温材料研究所北京100081

采用Gleeble-1500热模拟机对GH674高温合金在应变速率为0.01s-1～1.0s-1、变形温度为950℃～1200℃、真应变为1的条件下的热变形行为进行了研究.结果表明,在试验研究的变形条件下,GH674型高温合金在热压缩变形过程中发生明显的动态再结... 详细信息

采用Gleeble-1500热模拟机对GH674高温合金在应变速率为0.01s-1～1.0s-1、变形温度为950℃～1200℃、真应变为1的条件下的热变形行为进行了研究.结果表明,在试验研究的变形条件下,GH674型高温合金在热压缩变形过程中发生明显的动态再结晶;用Zener-Hollomon参数的指数函数能较好地描述该合金高温变形时的流变行为;所获得的峰值应力热变形方程为σp＝21.3139ln+9.580495×105/Τ-538.11638;其热变形激活能Q为373.7102803kJ/mol.

关键词： GH674高温合金热压缩变形流变应力 Zener—Hollomon参数热变形激活能

High-throughput screening of CO_(2) cycloaddition MOF catalyst with an explainable machine learning model

在线全文

学校读者我要写书评

暂无评论

Green Energy & Environment 2025年第1期10卷 132-138页

作者： Xuefeng Bai Yi li Yabo Xie Qiancheng Chen Xin Zhang Jian-rong li Beijing Key Laboratory for Green Catalysis and Separation and Department of Chemical Engineering College of Materials Science&EngineeringBeijing University of TechnologyBeijing100124China

The high porosity and tunable chemical functionality of metal-organic frameworks(MOFs)make it a promising catalyst design ***-throughput screening of catalytic performance is feasible since the large MOF structure database is *** this study,we report a machine learning model for high-throughput screening of MOF catalysts for the CO_(2) cycloaddition *** descriptors for model training were judiciously chosen according to the reaction mechanism,which leads to high accuracy up to 97%for the 75%quantile of the training set as the classification *** feature contribution was further evaluated with SHAP and PDP analysis to provide a certain physical understanding.12,415 hypothetical MOF structures and 100 reported MOFs were evaluated under 100℃ and 1 bar within one day using the model,and 239 potentially efficient catalysts were *** them,MOF-76(Y)achieved the top performance experimentally among reported MOFs,in good agreement with the prediction.

关键词： Metal-organic frameworks High-throughput screening Machine learning Explainable model CO_(2)cycloaddition

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

多特征融合的鲁棒图像匹配

科学技术与工程 2012年第32期20卷 8746-8749页

作者：李长荣齐齐哈尔大学计控学院齐齐哈尔161006

针对三种常见的图像匹配方法的优缺点进行了分析。然后利用一种常用的数据融合方法——DS理论,对匹配结果进行融合判断。最终形成了一种融合匹配算法,从而克服了单个特征和算法的局限性,实现了多特征、多算法优势互补,提高了匹配的适应性。

关键词：图像匹配信息融合多特征

在线全文

学校读者我要写书评

暂无评论

稀土Ce元素对钢中夹杂物变质的影响

材料热处理学报 2018年第10期39卷 75-79页

作者：李中元李长荣贵州大学材料与冶金学院贵州贵阳550025 贵州省冶金工程与过程节能重点实验室贵州贵阳550025

通过FactSage热力学计算,分析了稀土Ce元素对钢中夹杂物生成顺序及夹杂物变质的影响,利用扫描电镜和能谱仪（SEM-EDS）等对其物相进行表征分析。结果表明,加入稀土Ce元素后,钢中可能生成夹杂物的热力学排列顺序为CeAlO_3〉Al_2O_3〉CeO_... 详细信息

通过FactSage热力学计算,分析了稀土Ce元素对钢中夹杂物生成顺序及夹杂物变质的影响,利用扫描电镜和能谱仪（SEM-EDS）等对其物相进行表征分析。结果表明,加入稀土Ce元素后,钢中可能生成夹杂物的热力学排列顺序为CeAlO_3〉Al_2O_3〉CeO_2〉Ce_2O_3〉MnS。稀土Ce元素对硫、氧夹杂物的形态和尺寸起到了一定的变质作用,在钢基体中呈现弥散球状化,把近一半数量的夹杂物粒径控制在2～3μm。使钢材性能得到了提高。

关键词：稀土Ce元素热力学计算夹杂物变质