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Journal of Natural Gas Chemistry 2010年第5期19卷 487-492页

作者： Lili Wang Wen Ding Yingwei Liu Weiping Fang yiquan yang Department of Chemical and Biochemical Engineering College of Chemistry and Chemical Engineering Xiamen University Xiamen 361005 Fujian China Department of Chemistry College of Chemistry and Chemical Engineering and National Engineering Laboratory for Green Chemical Productions of Alcohols Ethers and Esters Xiamen University Xiamen 361005 Fujian China

Various Cu/ZnO/Al2O3 catalysts have been synthesized by different aluminum emulsions as aluminum sources and their pertormances tor methanol synthesis from syngas have been investigated. The influences of preparation methods of aluminum emulsions on physicochemical and catalytic properties of catalysts were studied by XRD, SEM, XPS,N2 adsorption-desorption techniques and methanol synthesis from syngas. The preparation methods of aluminum emulsions were found to influence the catalytic activity, CuO crystallite size, surface area and Cu0 surface area and reduction process. The results show that the catalyst CN using the aluminum source prepared by addition the ammonia into the aluminum nitrate （NP） exhibited the best catalytic performance for methanol synthesis from syngas.

关键词： aluminum emulsion copper-based catalysts methanol synthesis Cu+/Cu0

Potassium-decorated active carbon supported Co-Mo-based catalyst for water-gas shift reaction

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Journal of Natural Gas Chemistry 2011年第1期20卷 77-83页

作者： Yixin Lian RuiFen Xiao Weiping Fang yiquan yang National Engineering Laboratory for Green Chemical Productions of Alcohols Ethers and Esters College of Chemistry and Chemical Engineering Xiamen University Xiamen 361005 Fujian China Minnan Science and Technology Institute Fujian Normal University Quanzhou 362332 Fujian China

The effect of potassium-decoration was studied on the activity of water-gas shift （WGS） reaction over the Co-Mo-based catalysts supported on active carbon （AC）, which was prepared by incipient wetness co-impregnation method. The decoration of potassium on active carbon in advance enhances the activities of the CoMo-K/AC catalysts for WGS reaction. Highest activity （about 92% conversion） was obtained at 250 ？ C for the catalyst with an optimum K 2 O/AC weight ratio in the range from 0.12 to 0.15. The catalysts were characterized by TPR and EPR, and the results show that activated carbon decorated with potassium makes Co-Mo species highly dispersed, and thus easily reduced and sulfurized. XRD results show that an appropriate content of potassium-decoration on active carbon supports may favors the formation of highly dispersed Co 9 S 8 -type structures which are situated on the edge or a site in contact with MoS 2 , K-Mo-O-S, Mo-S-K phase. Those active species are responsible for the high activity of CoMo-K/AC catalysts.

关键词： active carbon potassium-decorated active phase Co-Mo-based catalyst water-gas shift

Effect of Mg/Al atom ratio of support on catalytic performance of Co-Mo/MgO-Al_2O_3 catalyst for water gas shift reaction

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Journal of Natural Gas Chemistry 2009年第2期18卷 161-166页

作者： Yixin Lian Huifang Wang Quanxing Zheng Weiping Fang yiquan yang Department of Chemistry College of Chemistry and Chemical Engineering National Engineering Laboratory for Green Chemical Productions of Alcohols Ethers and Esters Xiamen University Xiamen 361005 Fujian China

Co-Mo-based catalysts supported on mixed oxide supports MgO-Al2O3 with different Mg/Al atom ratios for water gas shift reaction were studied by means of TPR, Raman, XPS and ESR. It was found that the octahedral Mo species in oxidized Co-Mo/MgO（x）-Al2O3 catalyst and the contents of Mo^5＋, Mo^4＋, S^2- and S^2-2 species in the functioning catalysts increased with increasing the Mg/Al atom ratio of the support under the studied experimental conditions. This is favorable for the formation of the active Co-Mo-S phase of the catalysts. Catalytic performance testing results showed that the catalysts Co-Mo/MgO-Al2O3 with the Mg/Al atom ratio of the support in the range of 0.475-0.525 exhibited optimal catalytic activity for the reaction.

关键词： Co-Mo catalyst reduction sulfidation mixed support water gas shift

Study on Ni/C catalysts for vapor phase carbonylation of ethanol

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Journal of Natural Gas Chemistry 2008年第4期17卷 355-358页

作者： Qing Zhang Huifang Wang Guosong Sun Kelin Huang Weiping Fang yiquan yang College of Chemistry and Chemical Engineering Xiamen University Xiamen 361005 Fujian China Guangxi Research Institute of Chemical Industry Nanning 530001 Guangxi China

Activated carbon-supported Ni catalysts for vapor phase carbonylation of ethanol to propionic acid in the presence of ethyl iodide as promoter were investigated. Under optimum reaction conditions, the conversions of carbon monoxide and ethanol were measured to be 81.4% and 98.4%, respectively, while the selectivity for propionic acid was found to be 98.65%. The catalyst was stable within 48 h on stream. XRD and XPS methods were used to characterize the structures and surface properties of the fresh and tested catalysts. The characterization results indicated that aggregation of nickel particles and formation of nickel iodide on the catalyst surface should be responsible for the deactivation of the catalysts.

关键词： ethanol carbonylation nickel propionic acid deactivation

Finite element analysis of trans-lamina cribrosa pressure difference on optic nerve head biomechanics: the Beijing Intracranial and Intraocular Pressure Study

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Science China(Life Sciences) 2020年第12期63卷 1887-1894页

作者： Yingyan Mao Diya yang Jing Li Jun Liu Ruowu Hou Zheng Zhang yiquan yang Lei Tian Robert N.Weinreb Ningli Wang Beijing Institute of Ophthalmology Beijing Tongren HospitalCapital Medical UniversityBeijing 100005China Beijing Ophthalmology and Visual Sciences Key Laboratory Beijing Tongren Eye CenterBeijing Tongren HospitalCapital Medical UniversityBeijing 100054China Department of Ophthalmology The Ohio State UniversityColumbus 43210USA Department of Neurosurgery Beijing Tongren HospitalCapital Medical UniversityBeijing 100005China Hamilton Glaucoma Center and Department of Ophthalmology University of California-San DiegoLa JollaCalifornia 92093USA

The present study aims to assess the potential difference of biomechanical response of the optic nerve head to the same level of trans-lamina cribrosa pressure difference(TLCPD) induced by a reduced cerebrospinal fluid pressure(CSFP) or an elevated intraocular pressure(IOP). A finite element model of optic nerve head tissue(pre-and post-laminar neural tissue, lamina cribrosa, sclera, and pia mater) was constructed. Computed stresses, deformations, and strains were compared at each TLCPD step caused by reduced CSFP or elevated IOP. The results showed that elevating TLCPD increased the strain in optic nerve head,with the largest strains occurring in the neural tissue around the sclera ring. Relative to a baseline TLCPD of 10 mmHg, at a same TLCPD of 18 mmHg, the pre-laminar neural tissue experienced 11.10% first principal strain by reduced CSFP and 13.66% by elevated IOP, respectively. The corresponding values for lamina cribrosa were 6.09% and 6.91%. In conclusion, TLCPD has a significant biomechanical impact on optic nerve head tissue and, more prominently, within the pre-laminar neural tissue and lamina cribrosa. Comparatively, reducing CSFP showed smaller strain than elevating IOP even at a same level of TLCPD on ONH tissue, indicating a different potential role of low CSFP in the pathogenesis of glaucoma.

关键词： cerebrospinal fluid pressure glaucomatous optic neuropathy laminar cribrosa trans-laminar cribrosa pressure difference

Retinal microvasculature is a potential biomarker for acute mountain sickness

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Science China(Life Sciences) 2023年第6期66卷 1290-1302页

作者： Yuan Xie Diya yang Alex S.Huang yiquan yang Ying Han Yunxiao Sun Kai Cao Huaizhou Wang Shizheng Wu Qiang Zhu Guozhong Wang Tianyi Wu Ningli Wang Beijing Tongren Eye Center Beijing Tongren HospitalCapital Medical UniversityBeijing Ophthalmology and Visual Sciences Key LaboratoryBeijing100730China Beijing Institute of Ophthalmology Beijing Tongren HospitalCapital Medical UniversityBeijing100005China The Viterbi Family Department of Ophthalmology Shiley Eye InstituteUniversity of CaliforniaSan DiegoCA92121USA Department of Ophthalmology University of CaliforniaSan FranciscoCA94143USA Institution of Geriatric Qinghai Provincial Hospital Xining810007China Department of Ultrasound Beijing Tongren HospitalCapital Medical UniversityBeijing100730China Department of Hyperbaric and Hypobaric Chamber Civil Aviation General HospitalBeijing100025China National Key Laboratory of High Altitude Medicine China High Altitude Medical Research InstituteXining810012China

Increased cerebral blood flow resulting from altered capillary level autoregulation at high altitudes leads to capillary overperfusion and then vasogenic cerebral edema,which is the leading hypothesis of acute mountain sickness(AMS).However,studies on cerebral blood flow in AMS have been mostly restricted to gross cerebrovascular endpoints as opposed to the *** study aimed to investigate ocular microcirculation alterations,the only visualized capillaries in the central neural system(CNS),during early-stage AMS using a hypobaric *** study found that after high altitude simulation,the optic nerve showed retinal nerve fiber layer thickening(P=0.004–0.018)in some locations,and the area of the optic nerve subarachnoid space(P=0.004)*** coherence tomography angiography(OCTA)showed increased retinal radial peripapillary capillary(RPC)flow density(P=0.003–0.046),particularly on the nasal side of the *** AMSpositive group had the largest increases in RPC flow density in the nasal sector(AMS-positive,?3.21±2.37;AMS-negative,?0.01±2.16,P=0.004).Among multiple ocular changes,OCTA increase in RPC flow density was associated with simulated early-stage AMS symptoms(beta=0.222,95%CI,0.009–0.435,P=0.042).The area under the receiver operating characteristics curve(AUC)for the changes in RPC flow density to predict early-stage AMS outcomes was 0.882(95%CI,0.746–0.998).The results further confirmed that overperfusion of microvascular beds is the key pathophysiologic change in early-stage *** OCTA endpoints may serve as a rapid,noninvasive potential biomarker for CNS microvascular changes and AMS development during risk assessment of individuals at high altitudes.

关键词： optical coherence tomography angiography retinal microvasculature acute mountain sickness

Water gas shift activity of Co-Mo/MgO-Al_2O_3 catalysts presulfided with ammonium sulfide

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Journal of Natural Gas Chemistry 2010年第1期19卷 61-66页

作者： Yixin Lian, Huifang Wang, Weiping Fang, yiquan yang Department of Chemistry, College of Chemistry and Chemical Engineering, National Engineering Laboratory for Green Chemical Productions of Alcohols, Ethers and Esters, Xiamen University, Xiamen 361005, Fujian, China [a] Department of Chemistry College of Chemistry and Chemical Engineering National Engineering Laboratory for Green Chemical Productions of Alcohols Ethers and Esters Xiamen University Xiamen 361005 Fujian China

Co-Mo/MgO-Al2O3 catalyst was presulfided with ammonium sulfide in aqueous solution and activated with synthesis gas for water gas shift reaction. The assay results indicate that the presulfided Co-Mo/MgO-Al2O3 catalyst exhibits an excellent catalytic activity and stability. XRD and EPR characterization results show that the O-S exchange might occur during the impregnation, leading to the formation of （NH4）2MoS4 （or （NH4）zMoxSy） precursor, which was then thermally decomposed and reduced to MoS2. The higher catalytic performance is attributed to an optimization formation of active Co-Mo sulfides, consisting of well dispersed MoS2 and Co-Mo-S phase due to the redispersion of Co sulfide particles over the edges of newly formed MoS2 crystallites.

关键词： Co-Mo-based catalyst ammonium sulfide presulfidation water-gas shift

特殊自然环境对眼压的影响及其机制的研究进展

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中华眼科杂志 2022年第11期58卷 949-953页

作者：杨一佺王宁利首都医科大学附属北京同仁医院北京同仁眼科中心北京市眼科研究所北京市眼科学与视觉科学重点实验室北京100730

随着人类探索和活动范围不断扩大, 越来越多人群在特殊自然环境中工作和生活。特殊自然环境有其相对独特的环境特点, 不仅可导致人机体发生病理生理变化和新陈代谢紊乱, 而且可对眼部造成影响, 需要关注维持正常视功能。本文总结了高原... 详细信息

随着人类探索和活动范围不断扩大, 越来越多人群在特殊自然环境中工作和生活。特殊自然环境有其相对独特的环境特点, 不仅可导致人机体发生病理生理变化和新陈代谢紊乱, 而且可对眼部造成影响, 需要关注维持正常视功能。本文总结了高原缺氧、太空微重力、深水、黑暗、寒冷及空气污染等特殊自然环境对眼压的影响, 并探讨眼压在这些特殊自然环境下改变的机制, 以期为临床诊疗和研究工作提供参考。

关键词：眼内压高海拔失重黑暗空气污染

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钴钼基水煤气变换催化剂及其催化反应工艺

石油化工 2011年第4期40卷 347-357页

作者：连奕新杨意泉方维平厦门大学化学化工学院醇醚酯化工清洁生产国家工程实验室福建厦门361005

介绍了国内外CO变换催化剂的发展及其在不同变换工艺中的应用,阐述了Co-M o基催化剂的催化机理与硫化方法。通过综合分析中温变换、中温变换串联低温变换、中温变换串联两段低温变换和全程低温变换4种代表性的工艺流程,提出了高效节能... 详细信息

介绍了国内外CO变换催化剂的发展及其在不同变换工艺中的应用,阐述了Co-M o基催化剂的催化机理与硫化方法。通过综合分析中温变换、中温变换串联低温变换、中温变换串联两段低温变换和全程低温变换4种代表性的工艺流程,提出了高效节能型的全程低温变换工艺将是变换技术的发展方向,开发适应全程低温变换工艺的高活性和高稳定性的Co-M o基变换催化剂及其预硫化技术是今后的主要研究目标。

关键词：水煤气变换钴钼基催化剂全程低温变换一氧化碳氧气二氧化碳

载体焙烧温度对Co-Mo/MgO-Al2O3变换催化剂性能的影响

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催化学报 2009年第6期30卷 549-554页

作者：连奕新王会芳方维平杨意泉厦门大学化学化工学院化学系、醇醚酯清洁生产国家工程实验室福建厦门361005

通过X射线衍射、N2吸附-脱附、程序升温脱附、程序升温还原和电子顺磁共振方法研究了焙烧温度对MgO-Al2O3载体物化结构和Co-Mo/MgO-Al2O3变换催化剂性能的影响.结果表明,在600～800oC范围内焙烧的复合氧化物以MgAl2O4-xMgO-yAl2O3无定... 详细信息

通过X射线衍射、N2吸附-脱附、程序升温脱附、程序升温还原和电子顺磁共振方法研究了焙烧温度对MgO-Al2O3载体物化结构和Co-Mo/MgO-Al2O3变换催化剂性能的影响.结果表明,在600～800oC范围内焙烧的复合氧化物以MgAl2O4-xMgO-yAl2O3无定形形式存在,载体表面存在较多的中强酸-碱位,相应的负载催化剂具有较高的水煤气变换活性.在氧化态催化剂中存在较多八面体结构的Mo物种,而硫化态催化剂中含有较多氧硫包围的Mo物种.这些钼物种与催化剂的活性紧密相关.

关键词：氧化镁氧化铝尖晶石钴钼基催化剂水煤气变换