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Tungsten Promoted Ni/Al_2O_3 Catalysts for Carbon Dioxide Reforming of Methane to Synthesis Gas

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Chemical Research in Chinese Universities 2004年第4期20卷 470-477页

作者： Thomas Suhartanto Andrew P. E. York Malcolm l. H. Green Wolfson Catalysis Centre Inorganic Chemistry Laboratory University of OxfordWolfson Catalysis Centre Inorganic Chemistry Laboratory University of OxfordWolfson Catalysis Centre Inorganic Chemistry Laboratory University of Oxford South Parks Road Oxford OX1 3QR UKSouth Parks Road Oxford OX1 3QR UKSouth Parks Road Oxford OX1 3QR UK

A series of tungsten promoted alumina supported nickel catalysts has been prepared for the carbon dioxide reforming of methane to synthesis gas. The catalysts have been characterized by means of XRD, TEM, and laser Raman spectroscopy. It is shown that the addition of tungsten to the nickel catalyst can stabilize the catalyst and increase the resistance to carbon deposition. Adding a suitable amount of tungsten can also increase the catalyst activity to be close to that of supported noble metal catalysts. The carburisation of the tungsten modified nickel catalyst decreases the catalyst activity at lower reaction temperatures(lyst performance at higher reaction temperatures. The alumina supported nickel catalyst modified by 0.67%(mass fraction) WO_3 has the equivalent equilibrium constant of the dry reforming reaction to that of alumina supported 5%(mass fraction) Ru at 873 K, and also has a lower activation energy for dry reforming than the latter.

关键词： Nickel catalyst Tungsten modifier CO_2 reforming Methane Syngas

Cosmological applications in Kaluza-Klein theory

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Chinese Physics B 2012年第4期21卷 631-637页

作者： M. I. Wanas Gamal G. l. Nashed A. A. Nowaya Astronomy Department Faculty of Science Cairo University Giza Egypt Mathematics Department Faculty of Science Ain Shams University Cairo 11566 Egypt Center for Theoretical Physics British University of Egypt Sherouk City 11837 P.O. Box 43 Egypt Mathematics Department Faculty of Science King Faisal University P.O. Box 380 Al-Ahsaa 31982 the Kingdom of Saudi Arabia Egyptian Relativity Group (ERG) Physics Department Faculty of Science Monofia University Monofia Egypt

The field equations of Kaluz-Klein （KK） theory have been applied in the domain of cosmology. These equations are solved for a fiat universe by taking the gravitational and the cosmological constants as a function of time t. We use Taylor＇s expansion of cosmological function, A（t）, up to the first order of the time t. The cosmological parameters are calculated and some cosmological problems are discussed.

关键词： Kaluz-Klein theory cosmology Taylor's expansion of cosmological function

light hydrocarbon in ore-forming fluids and its constraints on ore genesis——A case study on Changkeng large-scale Au-Ag deposit, central Guangdong, China

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Chinese Science Bulletin 1999年第S2期44卷 58-61页

作者： D. l. Norman Department of Earth & Environmental Sciences New Mexico Institute of Mining & Technology (NMT) Socorro NM87801 USA

ORGANIC matters in the ore-forming fluids are composed mainly of light hydrocarbons. Because of the small amount of hydrocarbons in fluid inclusions, it is quite difficult to study their behavior in mineralizing processes, excepting methane （CH4）. In this work, we used a high vacuum quadrupole gas massspectrometer system to determine the content and composition of light hydrocarbons (C1-7) in fluid inclusions in minerals collected from Changkeng Au-Ag deposit. The geological significance of the new data forgenesis of the deposit has been discussed briefly.

关键词： light hydrocarbons ore-forming fluid ore genesis Changkeng Au-Ag deposit.

Silicon saturation coefficient changes in hydrogarnets during the Bayer process with lime addition

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Chinese Journal of Chemical Engineering 2019年第8期27卷 1965-1972页

作者： Guozhi lü Ting’an Zhang Xiaofeng Zhu Chaozhen Zheng Yanxiu Wang Weiguang Zhang Zimu Zhang Key laboratory of Ecological Metallurgy of Multi-metal Intergrown Ores of Ministry of Education School of Metallurgy Northeastern University

The relationship between the silicon saturation coefficient of hydrogarnets and Bayer reaction parameters was studied. The peak position, crystal plane spacing, and cell edge length of typical hydrogarnet patterns were calculated to find the key factors influencing the relationship. The results showed that the crystal face(420) is the optimal garnet growth direction during hydration and crystal growth along the faces(521) and(611) were not affected significantly by the varying experimental conditions. The reaction temperature significantly influenced the silicon saturation coefficient of hydrogarnets. The silicon saturation coefficient of hydrogarnets increased from 0.2 to about 1.0 in the temperature range of 30–270 °C and a rapid expansion process was observed in the temperature range of 120–150 °C. Moreover, the reaction time, alumina concentration, and C/S were shown to be less important factors. Averaging the results obtained by the 3 methods was shown suitable for calculating the SiO2 saturation coefficient of hydrogarnets. The calculated results of the Al2O3 and SiO2 contents matched the actual ones. However, the actual SiO2 content was about10 % less than the calculated one for SiO2 saturation coefficients higher than 1.

关键词： Hydrogarnet Saturation coefficient Peak position Crystal plane spacing Cell edge length

恩替卡韦治疗后慢性乙型肝炎低病毒血症患者序贯联合艾米替诺福韦治疗的效果研究

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中国现代医学杂志 2024年第8期34卷 15-20页

作者：向文耀李仕雄吕日英贵港市人民医院感染科广西贵港537100

目的探讨在恩替卡韦(ETV)治疗后出现低病毒血症(llV)的慢性乙型肝炎(CHB)患者,采取序贯联合艾米替诺福韦(TMF)治疗的临床效果。方法选取2021年7月—2023年1月在贵港市人民医院感染科经ETV抗病毒治疗的CHB患者200例。根据治疗期间HBV ... 详细信息

目的探讨在恩替卡韦(ETV)治疗后出现低病毒血症(llV)的慢性乙型肝炎(CHB)患者,采取序贯联合艾米替诺福韦(TMF)治疗的临床效果。方法选取2021年7月—2023年1月在贵港市人民医院感染科经ETV抗病毒治疗的CHB患者200例。根据治疗期间HBV DNA水平,将患者分为完全病毒学应答组(64例)和llV组(136例),分析两组临床资料。根据llV组抗病毒治疗方案,分为3组:续用ETV为对照组(40例)、换用TMF为序贯组(45例)、ETV联合TMF为联合组(51例),持续治疗48周。比较3组治疗48周时HBV DNA转阴率、乙肝表面抗原(HBsAg)、E抗原(HBeAg)、丙氨酸转氨酶(AlT)、天冬氨酸转氨酶(AST)、肌酐(Cr)和肝硬度测定值(lSM)及不良反应发生率。结果完全病毒学应答组HBeAg阳性率、HBV DNA、PlT、lSM、AlT、AST均低于llV组(P lT均低于llV组(P lT、AST均低于对照组(P lT均高于对照组(P lSM低于对照组(P 0.05)。结论序贯或联合TMF治疗能更有效地提高ETV治疗后llV患者完全病毒学应答率,并改善患者肝肾功能,减轻肝纤维化程度。

关键词：慢性乙型肝炎低病毒血症恩替卡韦艾米替诺福韦肝功能

延胡索去甲乌药碱合成酶基因CyNCS1克隆及其表达模式分析

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西北农林科技大学学报（自然科学版） 2024年第3期52卷 146-154页

作者：冯飞雪吕瑞华李依民高静王凯周嘉迪颜永刚张岗陕西中医药大学附属医院陕西咸阳712046 陕西中医药大学医学技术学院陕西咸阳712046 陕西中医药大学药学院/陕西省中医药管理局“秦药”研发重点实验室陕西咸阳712046

【目的】克隆延胡索去甲乌药碱合成酶(norcoclaurine synthase, NCS)基因,分析其在延胡索异喹啉类生物碱合成中的关键作用。【方法】基于转录组数据库,利用逆转录PCR克隆延胡索CyNCS1基因及其启动子区域序列,采用生物信息学方法分析其... 详细信息

【目的】克隆延胡索去甲乌药碱合成酶(norcoclaurine synthase, NCS)基因,分析其在延胡索异喹啉类生物碱合成中的关键作用。【方法】基于转录组数据库,利用逆转录PCR克隆延胡索CyNCS1基因及其启动子区域序列,采用生物信息学方法分析其编码蛋白的理化性质、结构特征及其启动子区域顺式作用元件,同时进行多序列比对和系统进化树分析,确定其进化关系;利用实时荧光定量PCR对其根、茎、叶及发育早、中、晚期块茎的组织表达模式进行分析;对茉莉酸甲酯(MeJA)、脱落酸(ABA)处理0,4,8,12 h的叶片进行表达谱分析,以体积分数75%酒精溶剂处理为对照(CK),确定该基因的表达特征。【结果】CyNCS1基因开放读码框长873 bp,编码291个氨基酸,编码蛋白分子量为33.09 ku,等电点为6.90,具有去甲乌药碱合成酶保守的催化结构域(GDGGVGTV/Il、YKEKF和MIEGGHlDMG),且不含信号肽,预测定位于细胞核中。多序列比对结果显示,CyNCS1与石生黄堇、罂粟的NCS蛋白同源性较高,分别为83.6%和82.1%;系统进化树结果显示,CyNCS1与石生黄堇CsNCS蛋白聚为一支,说明二者亲缘关系较近。该基因启动子区长2 238 bp,包含多种植物激素及低温、热胁迫等环境因子的顺式作用元件。实时荧光定量PCR结果显示,随着发育推进块茎中CyNCS1的表达量显著增高,且受到MeJA和ABA的诱导,MeJA处理8 h时表达量为0 h的3.10倍,ABA处理8 h为0 h的3.16倍;而对照CyNCS1表达量随时间推移无明显变化。【结论】克隆并鉴定了延胡索NCS酶基因CyNCS1,明确了其在发育进程中的表达模式,并确定该基因表达受MeJA和ABA的诱导。

关键词：延胡索去甲乌药碱合成酶异喹啉生物碱启动子顺式作用元件

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Proto-Adamastor ocean crust(920 Ma)described in Brasiliano Orogen from coetaneous zircon and tourmaline

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Geoscience Frontiers 2019年第4期10卷 1623-1633页

作者： léo A.Hartmann Mariana Werle Cassiana R.l. Michelin Cristiano lana Gláucia N. Queiroga Marco P. Castro Karine R. Arena Instituto de Geociências Universidade Federal do Rio Grande do SulAvenida Bento Goncalves950091501-970Porto AlegreRio Grande do SulBrazil Departamento de Geologia Escola de MinasUniversidade Federal de Ouro PretoMorro do Cruzeiro35400-000Ouro PretoMinas GeraisBrazil

Proto-Adamastor ocean bathed Rodinia and successor continental fragments from 1.0-0.9 Ga up to0.75 Ga,and evolved into world Adamastor Ocean at 0.75-0.60 *** oceanic crust is poorly preserved on continents,only indirect evidence registered in Brasiliano *** report first evidence of ophiolite originated in *** use multi-technique U-Pb-Hf zircon andδ^11B tourmaline isotopic and elemental *** host tourmalinite is enclosed in metaserpentinite,both belonging to the Bossoroca *** is 920 Ma-old,εHf(920 Ma)=+12,HfTDM=1.0 Ga and has’oceanic’composition(e.g.,U/Ybline is dravite withδ^11B=+1.8‰(Tur 1),0‰(Tur 2),-8.5‰(Tur 3).These characteristics are a novel contribution to Rodinia and associated world ocean,because a fragment of proto-Adamastor oceanic crust and mantle evolved at the beginning of the Brasiliano Orogen.

关键词： Coeval zircon and tourmaline Bossoroca ophiolite Early Brasiliano Orogen Zircon U-Pb-Hf isotopes Zircon trace elements Tourmaline boron isotopes

烟酰胺核糖对MPP^(+)诱导SH-SY5Y细胞损伤的保护及机制研究

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中国现代医学杂志 2024年第17期34卷 61-66页

作者：杨艳梅隋易航吕志宇西南医科大学附属医院神经内科四川泸州646000

目的探究烟酰胺核糖(NR)对1-甲基-4-苯基-吡啶离子(MPP^(+))诱导的SH-SY5Y细胞损伤的保护作用及其潜在机制。方法取对数生长期的H-SY5Y细胞来完成实验,使用3 mmol/l MPP^(+)处理细胞构建帕金森病(PD)体外模型。细胞分为对照组(常规培养)... 详细信息

目的探究烟酰胺核糖(NR)对1-甲基-4-苯基-吡啶离子(MPP^(+))诱导的SH-SY5Y细胞损伤的保护作用及其潜在机制。方法取对数生长期的H-SY5Y细胞来完成实验,使用3 mmol/l MPP^(+)处理细胞构建帕金森病(PD)体外模型。细胞分为对照组(常规培养)、MPP^(+)组(MPP^(+)处理)、实验组(0.5 mmol/l NR和MPP^(+)处理)。细胞培养后检测细胞存活率、凋亡率,氧化应激水平[活性氧(ROS)、丙二醛(MDA)、超氧化物歧化酶(SOD)],炎症水平[白细胞介素-6(Il-6)、肿瘤坏死因子-α(TNF-α)],烟酰胺腺嘌呤二核苷酸(NAD^(+))水平等指标。结果与对照组比较,MPP^(+)组细胞凋亡率、ROS、MDA、TNF-α、Il-6水平均升高(Pl-6水平均降低(P<0.05),细胞存活率、SOD、NAD^(+)水平均升高(P<0.05)。结论NR可以减轻MPP^(+)诱导的神经细胞损伤,其机制可能与补充NAD^(+)减轻细胞氧化应激和炎症反应有关。

关键词：帕金森病烟酰胺核糖 NAD^(+) 氧化应激

A novel method for improving cerussite sulfidization

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International Journal of Minerals,Metallurgy and Materials 2016年第6期23卷 609-617页

作者： Qi-cheng Feng Shu-ming Wen Wen-juan Zhao Qin-bo Cao Chao lü State Key laboratory of Complex Nonferrous Metal Resources Clean Utilization Kunming University of Science and Technology Kunming Metallurgical Research Institute

Evaluation of flotation behavior, solution measurements, and surface analyses were performed to investigate the effects of chloride ion addition on the sulfidization of cerussite in this study. Micro-flotation tests indicate that the addition of chloride ions prior to sulfidization can significantly increase the flotation recovery of cerussite, which is attributed to the formation of more lead sulfide species on the mineral surface. Solution measurement results suggest that the addition of chloride ions prior to sulfidization induces the transformation of more sulfide ions from pulp solution onto the mineral surface by the formation of more lead sulfide species. X-ray diffraction and energy-dispersive spectroscopy indicate that more lead sulfide species form on the mineral surface when chloride ions are added prior to sulfidization. These results demonstrate that the addition of chloride ions prior to sulfidization can significantly improve the sulfidization of cerussite, thereby enhancing the flotation performance.

关键词： cerussite sulfidization chloride surface analysis