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内蒙古阴山北麓草原植被净初级生产力变化特征及其气候驱动力

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水利水电技术（中英文） 2024年第8期55卷 38-50页

作者：范毅宁廖梓龙龙胤慧程瑶河北工程大学水利水电学院河北邯郸056038 河北工程大学河北省智慧水利重点实验室河北邯郸056038 水利部牧区水利科学研究所内蒙古呼和浩特010020 中国水利水电科学研究院内蒙古阴山北麓草原生态水文国家野外科学观测研究站北京100038

【目的】研究阴山北麓草原植被净初级生产力的时空变化特征,揭示气候、地形因子对植被NPP变化的影响,为内蒙古草原生态保护与可持续发展提供理论基础。【方法】基于MODIS NPP,气象及DEM数据,采用Theil-Sen Median趋势分析、M-K突变、地... 详细信息

【目的】研究阴山北麓草原植被净初级生产力的时空变化特征,揭示气候、地形因子对植被NPP变化的影响,为内蒙古草原生态保护与可持续发展提供理论基础。【方法】基于MODIS NPP,气象及DEM数据,采用Theil-Sen Median趋势分析、M-K突变、地理探测器以及Person相关分析等方法,阐明阴山北麓草原植被NPP的变化特征,并识别植被NPP的驱动因子。【结果】2001—2022年,阴山北麓草原植被NPP年均增加2.784 gC m-2a-1,增长速度较快的区域分布在东部及南部。植被NPP变化受降水、日照时数、最低气温、最高气温、地形等因子共同驱动。降水增加促进了植被NPP的增长,相关系数为0.639;最高气温与最低气温与植被NPP均呈轻微负相关,相关系数分别为-0.162、-0.051。【结论】阴山北麓草原植被NPP整体呈显著增加趋势,地形因子对植被NPP的驱动力不强,降水是植被NPP的主要驱动因子,降水与日照时数、最高气温、最低气温的交互作用显著影响植被NPP变化。

关键词：植被NPP 驱动力地理探测器阴山北麓草原影响因素降水气候变化时空变化

Honeycomb-shaped Pt Sn Na/y-Al2O3/cordierite monolithic catalyst with improved stability and selectivity for propane dehydrogenation

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Chinese Chemical Letters 2018年第6期29卷 884-886页

作者： Shiyong Zhao Bolian Xu Lei Yu yining fan Key Laboratory of Mesoscopic Chemistry of Ministry of Education School of Chemistry and Chemical EngineeringNanjing University Nanjing 210093. China Nanjing University-Yangzhou Chemistry and Chemical Engineering Institute. Yangzhou 211400. China School of Chemistry and Chemical Engineering. Yangzhou University. Yangzhou 225002 China

novel honeycomb-shaped Pt Sn Na/g-Al2 O3/cordierite monolithic catalyst（Pt 0.5%, Sn 0.9%, Na 1.0%,relative to Al2 O3 weight） was developed and its catalytic performances in propane dehydrogenation were tested and compared with the classical granule catalyst with same Pt, Sn and Na contents under the conditions of 0.1 MPa, 590C, C3 H8/H2 at 3/1（molar ratio） and gas hourly space velocity（GHSV） at155 h-1. Interestingly, despite the generated coke amount and exposed Pt fraction, the honey combshaped structure of monolithic catalyst exerted important influences on its catalytic activities and led to the advanced catalytic performances over the granule catalyst.

关键词： Propane dehydrogenation Propylene Platinum Cordierite Monolithic catalyst

Catalytic dehydrogenation of propane to propylene over highly active PtSnNa/γ-Al2O3 catalyst

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Chinese Chemical Letters 2018年第3期29卷 475-478页

作者： Shiyong Zhao Bolian Xu Lei YU yining fan Key Laboratory of Mesoscopic Chemistry of Ministry of Education School of Chemistry and Chemical Engineering Nanjing University Nanjing 210093 China Nanjing University-Yangzhou Chemistry and Chemical Engineering Institute Yangzhou 211400 China School of Chemistry and Chemical Engineering Yangzhou University Yangzhou 225002 China

PtSnNa/γ-Al2O3 catalyst is widely used in the dehydrogenation of light alkane. This paper reports a new fabrication method of the catalyst. In the work, γ-Al2O3, SnCl4 and NaCl were ball milled to upload Sn and Na＋ onto the support instead of the conventionally used immersion method. The subsequent baking procedures frimly fixed Sn onto the support, which could disperse Pt introduced by immersion. The effects of Sn and Na＋ additives on the catalytic performance of PtSnNa/y-Al2O3 catalyst were investigated. It was found that the appropriate molar ratio of Sn/Pt was 6：1 while the favorable weight percentage of Na＋ was 0.90%. Compared with the reaction catalyzed by the industrially employed PtSnNa/ γ-Al2O3 catalyst, the conversion of propane and the selectivity of propylene had been greatly improved, which were 26.97%; and 99.18% respectivelv after 12 h reaction.

关键词： Propane Propylene Dehydrogenation Platinum Aluminum oxide

Thermostable Nitrogen-Doped HTiNbO5 Nanosheets with a High Visible-Light Photocatalytic Activity

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Nano Research 2011年第7期4卷 635-647页

作者： Zheng Zhai Yucheng Huang Lin Xu Xiaoyan Yang Chenhui Hu Lihong Zhang yining fan Wenhua Hou Key Laboratory of Mesoscopic Chemistry of MOE School of Chemistry and Chemical Engineering Nanjing University Nanjing210093 China

Nitrogen-doped HTiNbO5 nanosheets have been successfully synthesized by first exfoliating layered HTiNbO5 in tetrabutylammonium hydroxide （TBAOH） to obtain HTiNbO5 nanosheets and then heating the nanosheets with urea. The resulting samples were characterized by X-ray diffraction （XRD）, transmission electron microscopy （TEM）, scanning electron microscopy （SEM）, energy-dispersive X-ray （EDX）, X-ray photoelectron spectroscopy （XPS）, UV-vis spectroscopy and N2 adsorption-desorption measurements. It was found that N-doping resulted in a much higher thermostability of the layered structure, intrinsic bandgap narrowing and a visible light response. The doped nitrogen atoms were mainly located in the interstitial sites of TiNbOs- lamellae and chemically bound to hydrogen ions. Compared with N-doped HTiNbOs, N-doped HTiNbO5 nanosheets had a much larger specific surface area and richer mesoporosity due to fee rather loose and irregular arrangement of fitanoniobate nanosheets. Both N-doped layered HTiNbOs and HTiNbO5 nanosheets showed a very high visible-light photocatalytic activity for the degradation of rhodamine B （RhB） aqueous solution. Moreover, due to the considerably larger surface area, richer mesoporosity and stronger acidity, N-doped HTiNbO5 nanosheets had an even higher activity than N-doped HTiNbOs, although the latter had a stronger absorption in the visible region. The dye molecules were mainly degraded to aliphatic organic compounds and partially mineralized to CO2 and/or CO, rather than being simply decolorized. The effect of photosensitization was insignificant and RhB was degraded mainly via the typical photocatalytic reaction routes. Two different reaction routes for the photodegradation of RhB under visible light irradiation over N-doped HTiNbO5 nanosheets have been proposed. The present method can be extended to a large number of layered metal oxides that have the characteristics of intercalation and exfoliation, thus providing new opportunities for the f

关键词： Layered titanoniobate nanosheets N-doping photodegradation visible light

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手工竹纸发展历程与研究现状

世界竹藤通讯 2024年第3期22卷 100-106页

作者：范怡宁韩宾葛梦帆姜润楠施继龙北京印刷学院北京102600 中国科学院大学北京100049

手工竹纸是我国传统手工纸的重要组成部分,其历史悠久,品类繁多,它的出现开创了以植物茎秆纤维造纸的新局面。2006年竹纸制作技艺被列为我国第1批国家级非物质文化遗产。为了探究竹纸的发展情况,进一步总结分析竹纸研究现状,更好地对竹... 详细信息

手工竹纸是我国传统手工纸的重要组成部分,其历史悠久,品类繁多,它的出现开创了以植物茎秆纤维造纸的新局面。2006年竹纸制作技艺被列为我国第1批国家级非物质文化遗产。为了探究竹纸的发展情况,进一步总结分析竹纸研究现状,更好地对竹纸进行保护和发展,文章归纳总结了手工竹纸的发展历程和制作工艺,并从竹纸制作工艺、竹纸保护修复和竹纸性能3个方面综述了手工竹纸的研究进展。分析发现,手工竹纸制作工艺的保护和传承问题越来越被重视,在其历史文化、生产工艺、现状及传承等方面已取得一定的研究进展;在竹纸性能分析方面,原料和制作工艺对纸张性能的内在影响已更加清晰,关于竹纸老化方向的研究明显增多,这与我国现存大量的竹纸类文物密不可分,但对于竹纸造纸原料方面的研究相对较为局限,对于造纸原料化学成分的分析有待进一步拓展。

关键词：手工竹纸发展历程制作工艺造纸原料性能分析

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Carbon dots confined nanosheets assembled NiCO_(2)S_(4)@CDs cross-stacked architecture for enhanced sodium ion storage

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Chinese Chemical Letters 2024年第7期35卷 508-513页

作者： Binyang Qin Mengqi Wang Shimei Wu yining Li Chilin Liu Yufei Zhang Haosen fan School of Chemistry and Chemical Engineering Guangzhou UniversityGuangzhou 510006China

Na^(+)batteries(SIBs)have been emerging as the most promising candidate for the next generation of secondary ***,the development of high-performance and cost-effective anode materials is urgently needed for the large-scale applications of *** this study,carbon dots confined bimetallic sulfide(NiCO_(2)S_(4))architecture(NiCO_(2)S_(4)@CDs)was proposed and synthesized from assembling nanosheets into cross-stacked superstructure and the subsequent confinement of carbon *** novel decussated structure assembly from nanosheets is greatly beneficial to the structure stability of electrode material during the successive charge/discharge ***,the CDs based carbon conductive network can enhance the electrical conductivity for facilitating the easy transport of electron/Na^(+).Benefitting from these advantages,NiCO_(2)S_(4)@CDs exhibits high-rate performance and an ultralong cycling life in ***,the specific capacity of NiCO_(2)S_(4)@CDs can reach the discharge specific capacity as high as 568.9 mAh/g at 0.5 A/g,which can also maintain 302.7 m Ah/g after 750 cycles at 5.0 A/***,ex-situ characterization techniques such as ex-situ XRD and ex-situ XPS were employed to further explore the sodium storage mechanism of the NiCO_(2)S_(4)@CDs anode.

关键词： Carbon dots Sodium ion batteries NiCo_(2)S_(4)@CDs Cross-stacked architecture Ex-situ XRD and XPS

不同孔道结构的氧化硅负载钒氧化物催化丙烷氧化脱氢

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催化学报 2009年第11期30卷 1143-1149页

作者：缪建文宋国华范以宁南通大学化学化工学院江苏南通226007 南京大学化学化工学院江苏南京210093 南通大学理学院江苏南通226001

采用固定床微型反应装置,结合催化剂的原位电子自旋共振光谱、程序升温表面反应和紫外漫反射光谱等技术,研究了丙烷氧化脱氢的介孔氧化硅负载钒氧化物催化剂的性能和表面氧物种的状态及其反应性.结果表明,催化剂载体孔结构是影响钒氧物... 详细信息

采用固定床微型反应装置,结合催化剂的原位电子自旋共振光谱、程序升温表面反应和紫外漫反射光谱等技术,研究了丙烷氧化脱氢的介孔氧化硅负载钒氧化物催化剂的性能和表面氧物种的状态及其反应性.结果表明,催化剂载体孔结构是影响钒氧物种分散状态乃至催化性能的一个重要因素.SBA-15负载钒氧化物催化剂因具有较大的比表面积和较大的孔径,不仅具有较高的丙烷氧化脱氢催化活性,而且具有较高的丙烯选择性.复合型钒氧化物催化剂表面与V离子相连的晶格氧物种是丙烷氧化脱氢生成丙烯的主要活性物种,载体表面高度分散的钒氧物种具有较高的丙烷氧化脱氢催化活性.负载型钒氧化物催化剂晶格氧物种是丙烷氧化脱氢转化为丙稀的主要活性物种,CO2分子可以再生钒氧化物催化剂的晶格氧物种,同时它对丙烯的深度氧化作用较弱,因此在负载型钒氧化物催化剂上CO2氧化丙烷可高选择性地生成丙烯.

关键词：丙烷氧化脱氢钒氧物种 SBA-15 电子自旋共振程序升温表面反应

载体组成对负载型PtSn/ZSM-5催化剂上丙烷脱氢反应性能的影响

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催化学报 2007年第11期28卷 970-974页

作者：邱安定李恩霞范以宁南京大学化学化工学院介观化学教育部重点实验室江苏省纳米技术重点实验室江苏南京210093

用微型催化反应装置结合吡啶吸附的红外光谱、NH3-程序升温脱附、热重、H2化学吸附和程序升温还原等物理化学手段研究了载体组成对负载型PtSn/ZSM-5催化剂上丙烷脱氢反应性能的影响.结果表明,负载型PtSn/ZSM-5催化剂对丙烷脱氢的催化性... 详细信息

用微型催化反应装置结合吡啶吸附的红外光谱、NH3-程序升温脱附、热重、H2化学吸附和程序升温还原等物理化学手段研究了载体组成对负载型PtSn/ZSM-5催化剂上丙烷脱氢反应性能的影响.结果表明,负载型PtSn/ZSM-5催化剂对丙烷脱氢的催化性能与载体组成密切相关.随着ZSM-5载体中SiO2/Al2O3比的增加,催化剂表面的酸中心总量和强酸中心量逐渐减少.当SiO2/Al2O3摩尔比从45增至108时,催化剂对丙烷脱氢反应的催化活性提高,并且催化剂的积炭量下降.当SiO2/Al2O3摩尔比增至304时,Sn组分与载体ZSM-5之间的相互作用减弱,经H2还原后催化剂中Sn0物种所占的比例增加,导致催化剂H2化学吸附量和丙烷脱氢反应活性下降.

关键词：铂锡 ZSM-5分子筛负载型催化剂丙烷脱氢丙烯

茅盾文学奖与当代中国现实主义文学的“审美共舞”

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小说评论 2020年第6期 76-88页

作者：范伊宁张丽军山东师范大学

茅盾文学奖评选了十届,跨度四十年,留下了哪些现实主义文学经典?这依然是一个不断被追问的当代文学热点问题。事实上,作为中国当代文坛长篇小说评选的重要奖项,茅盾文学奖的评选始终受到作家、批评家以及读者们的密切关注。自1982年评... 详细信息

茅盾文学奖评选了十届,跨度四十年,留下了哪些现实主义文学经典?这依然是一个不断被追问的当代文学热点问题。事实上,作为中国当代文坛长篇小说评选的重要奖项,茅盾文学奖的评选始终受到作家、批评家以及读者们的密切关注。自1982年评选以来,茅盾文学奖共评选出48部长篇小说(其中有两部作品获得的是荣誉奖)。

关键词：茅盾文学奖现实主义文学当代文学批评家当代文坛热点问题评选