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Hierarchically porous zeolites synthesized with carbon materials as templates

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Frontiers of Chemical Science and Engineering 2021年第6期15卷 1444-1461页

作者： Huan Wang guo du Jiaqing Jia Shaohua Chen Zhipeng Su Rui Chen Tiehong Chen Institute of New Catalytic Materials Science School of Materials Science and EngineeringKey Laboratory of Advanced Energy Materials Chemistry(MOE)Nankai UniversityTianjin300350China

Hierarchically porous zeolites are promising candidates in catalytic conversion of relatively bulky molecules,and their syntheses have attracted significant *** both industrial and scientific perspectives,different carbon materials have been widely employed as hard templates for the preparation of hierarchically porous zeolites during the past two *** this review,the progress in synthetic strategies using carbon materials as templates is comprehensively *** on the affinity between the carbon templates and zeolite precursors,the substantial strategies for synthesizing hierarchical zeolites are introduced in direct templates and indirect *** templates methods,by which the carbon materials are directly mixed with precursors gel as hard templates,are first ***,we discuss the indirect templates method(crystallization of carbon-silica composites),by which the carbon is produced by in situ pyrolysis of organic-inorganic *** addition,the technique of encapsulating metal species into zeolites crystals with the assistance of carbon templates is also *** the conclusion part,the factors affecting the synthesis of carbon-templated hierarchically porous zeolites are *** review is expected to attract interest in the synthesis strategies of hierarchically porous zeolites,especially cost-effective and large-scale production methodologies,which are essential to the industrial application of hierarchical zeolites.

关键词： hierarchical zeolites carbon materials direct templates indirect templates carbon-silica composites

Effects of Light on the Growth and Clonal Reproduction of Ligularia virgaurea

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Journal of Integrative Plant Biology 2008年第8期50卷 1015-1023页

作者： Man-Tang Wang Zhi-Gang Zhao guo-Zhen du Yan-Long He Key Laboratory of Arid and Grassland Agroecology under the Ministry of Education Lanzhou University Lanzhou 730000 China

Ligularia virgaurea is a perennial herb that is widely distributed in the alpine meadow on the eastern Qinghai-Tibet plateau. We investigated the patterns of growth and reproduction of L. virgaurea under two contrasting levels of light conditions for two continuous growing seasons. Our results showed that the light effects on the maximum relative growth rate, the shoot weight ratio and the root weight ratio differed between the two growing seasons. L. virgaurea reproduced initially through rhizome in the second growing season, rather than sexual reproduction. The proportion of genets with clonal reproduction decreased under shaded conditions. A minimum genet size should be attained for clonal reproduction to begin under the shaded conditions. There was a positive linear relationship between clonal reproduction and genet size. Light level affected the allocation of total biomass to clonal structures, with less allocation under the full natural irradiance than under the shaded conditions. There seemed to be a trade-off between vegetative growth and clonal reproduction under the full natural irradiance, in terms of smaller relative growth rates of genets with clonal reproduction than those without clonal reproduction. L. virgaurea emphasized clonal reproduction under the full natural irradiance, while the plant emphasized vegetative growth under the shaded conditions.

关键词： biomass allocation clonal reproduction Ligularia virgaurea relative growth rate threshold size

Covariance of Floral and Vegetative Traits in Four Species of Ranunculaceae:A Comparison between Specialized and Generalized Pollination Systems

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Journal of Integrative Plant Biology 2008年第9期50卷 1161-1170页

作者： Jin-Liu Meng Xian-Hui Zhou Zhi-Gang Zhao guo-Zhen du Key Laboratory of Arid and Grassland Ecology of Ministry of Education at Lanzhou University Lanzhou 730000 China College of Life Sciences Wuhan University Wuhan 430072 China

Theory predicts that tighter correlation between floral traits and weaker relationship between floral and vegetative traits more likely occur in specialized flowers than generalized flowers, favoring by precise fit with pollinators. However, traits and trait correlations frequently vary under different environments. Through detecting spatiotemporal variation in phenotypic traits （floral organ size and vegetative size） and trait correlations in four Ranunculaceae species, we examined four predictions. Overall, our results supported these predictions to a certain degree. The mean coefficient of variation （CV） of floral traits in two specialized species （Delphinium kamaonense and Aconitum gymnandrum） was marginally significantly lower than that of another two generalized species （Trollius ranunculoides and Anemone obtusiloba）. The two specialized species also showed marginally significantly smaller CV in floral traits than vegetative size across the two species. The absolute mean correlation between floral and vegetative traits, or that between floral traits in species with specialized flowers was not significantly lower, or higher than that in generalized plants, weakly supporting the predictions. Furthermore, we documented a large variation in trait correlations of four species among different seasons and populations. Study of covariance of floral and vegetative traits will benefit from the contrast of results obtained from generalized and specialized pollination systems.

关键词： coefficient of variation floral traits generalized flower Ranunculaceae specialized flower trait correlation vegetative traits.

The 3D nanoimaging beamline at SSRF

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Nuclear Science and Techniques 2023年第12期34卷 242-250页

作者： Ling Zhang Fen Tao Jun Wang Ruo‑Yang Gao Bo Su guo‑Hao du Ai‑guo Li Ti‑Qiao Xiao Biao Deng Shanghai Synchrotron Radiation Facility Shanghai Advanced Research InstituteChinese Academy of SciencesShanghai 201204China

Full-field transmission X-ray microscopy(TXM)is a powerful non-destructive three-dimensional(3D)imaging method with a nanoscale spatial resolution that has been used in most synchrotron facilities *** in-house-designed TXM system was constructed at the BL18B 3D nanoimaging beamline at the Shanghai Synchrotron Radiation *** beamline operates from 5 to 14 keV and enables 20 nm spatial resolution *** characterization details of the beamline are described in this *** performances in terms of spatial resolution,nano-CT,and nano-spectral imaging of the TXM beamline are also presented in this article.

关键词： Transmission X-ray microscopy(TXM) Nano-CT Synchrotron radiation

黄芪、枸杞、沙果果醋的研制及其抗氧化活性研究

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中国调味品 2024年第6期49卷 131-134页

作者：杜国军李占锋洪婉婷张以超蔡有杰齐齐哈尔大学食品与生物工程学院黑龙江齐齐哈尔161006

以黄芪、枸杞为原料,经混合、煎煮、抽滤、离心制取黄芪枸杞汁;将黄芪枸杞汁和沙果汁按比例混合,利用酵母菌和醋酸菌对其进行发酵,制备果醋。采用单因素试验与正交试验得到了最适工艺条件。研究结果表明,黄芪枸杞汁的最适制备工艺为黄... 详细信息

以黄芪、枸杞为原料,经混合、煎煮、抽滤、离心制取黄芪枸杞汁;将黄芪枸杞汁和沙果汁按比例混合,利用酵母菌和醋酸菌对其进行发酵,制备果醋。采用单因素试验与正交试验得到了最适工艺条件。研究结果表明,黄芪枸杞汁的最适制备工艺为黄芪与枸杞的比例1∶2、料液比1∶20、煎煮时间60 min;黄芪枸杞汁与沙果汁的最适比例为1∶5;最适酒精发酵条件为酵母菌接种量8%、发酵温度28℃、初始糖度14%、发酵时间6 d;最适醋酸发酵条件为醋酸菌接种量10%、发酵温度32℃、初始酒精度8%、摇床转速200 r/min;果胶酶添加量为200 mg/L时,果醋的透光率达到90.16%,在此条件下制得的产品颜色淡黄、酸甜适中、气味芳香,具有较强的抗氧化活性。

关键词：黄芪枸杞沙果果醋抗氧化活性

Field investigations and numerical modeling of a giant landslide in the region of Eastern Himalayan Syntaxis:Jiaobunong landslide

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Journal of Mountain Science 2021年第12期18卷 3230-3246页

作者： du guo-liang ZHANG Yong-shuang YAO Xin YANG Zhi-hua YUAN Ying Hebei GEO University Shijiazhuang 050031China Key Laboratory of Intelligent Detection and Equipment for Underground Space of Beijing-Tianjin-Hebei Urban Agglomeration Ministry of Natural ResourcesHebei GEO UniversityShijiazhuang 050031China Institute of Hydrogeology and Environmental Geology Chinese Academy of Geological SciencesShijiazhuang 050061China Institute of Geomechanics Chinese Academy of Geological SciencesBeijing 100081China

Eastern Himalayan Syntaxis(EHS)is a tectonically active region that undergoes continuous geomorphic *** landslides are predominant in this region.A giant landslide called Jiaobunong landslide on the northwestern flank of the EHS were studied and simulated to investigate the formation mechanism,evolutionary process,and failure mechanism of the landside,so that we could better understand the large complex ancient landslides in this *** investigation,geological background analyses,and numerical modeling were conducted to reveal the natural and seismic characteristics,as well as dynamic process of the *** results show that the Jiaobunong landslide was the result of long-term geological and geomorphic ***,river incision,weathering,fault creep,glaciation,and earthquakes play key roles in the formation of *** the huge landslide volume,strong seismicity of the study area,proximity to an active fault,and the need for extra forces to induce landsliding,the Jiaobunong landslide was triggered by a *** numerical simulation based on the discrete element method,the slope dynamic response of the earthquake as well as the mass movement and accumulation process was *** results showed that the landslide movement experienced four stages:initiation phase(0-5 s),acceleration phase(5-35 s),deceleration phase(35-95 s),and the compaction and self-stabilization stage(after 95 s).The rock mass was disintegrated and experienced strong collisions during the *** dammed lake gradually disappeared because of long-term river incision by the overtopping river *** processes play a vital role in the evolution of landforms in the region of EHS.

关键词： Eastern Himalayan syntaxis Ancient landslide Formation mechanism Evolution process Tibetan Plateau

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羧基化改性海带渣对结晶紫的吸附性能研究

粮食与油脂 2024年第5期37卷 84-90页

作者：杜国丰陈小焕梁飞龙尹梦琪杨杰书梁海营口理工学院化学与环境工程学院辽宁营口115014

采用丁二酸酐(SA)对海带渣(LJR)进行羧基化修饰。利用红外光谱、扫描电镜、能量色散光谱对LJR和改性海带渣(CLJR)进行表征,对比改性前后LJR对结晶紫(CV)的吸附性能,并确定CLJR的最优吸附条件。结果发现:CLJR在1728 cm^(-1)处出现羧基的... 详细信息

采用丁二酸酐(SA)对海带渣(LJR)进行羧基化修饰。利用红外光谱、扫描电镜、能量色散光谱对LJR和改性海带渣(CLJR)进行表征,对比改性前后LJR对结晶紫(CV)的吸附性能,并确定CLJR的最优吸附条件。结果发现:CLJR在1728 cm^(-1)处出现羧基的特征峰,孔隙结构明显增多,羧基化改性增强了LJR对CV的吸附性能。CLJR的最优吸附条件为初始质量浓度100 mg/L、吸附剂投加量0.8 g/L、初始pH 5~11;升高温度对LJR和CLJR的吸附过程有利。

关键词：海带渣羧基化改性吸附结晶紫吸附等温线

基于两阶段启发式算法的省电力物资周转库选址-路径优化研究

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物流工程与管理 2024年第3期46卷 4-7页

作者：张正利杜国政李涛曹刚国网山东省电力公司物资公司山东济南250001

省电力物资周转库是仓储网络架构的关键节点,文中研究带库存容量限制的周转库选址与考虑时间窗和装载量约束的车辆配送路径优化的组合决策问题,构建以配送总成本最小为目标的选址-路径问题模型,设计两阶段启发式算法进行求解。第一阶段... 详细信息

省电力物资周转库是仓储网络架构的关键节点,文中研究带库存容量限制的周转库选址与考虑时间窗和装载量约束的车辆配送路径优化的组合决策问题,构建以配送总成本最小为目标的选址-路径问题模型,设计两阶段启发式算法进行求解。第一阶段设计聚类-重心-搜索算法,求解带库存容量限制的省周转库选址问题;第二阶段采用自适应大邻域搜索算法,解决考虑时间窗和装载量约束车辆配送路径优化问题。基于S省2022年历史物流数据和已有仓储资源规模,采用两阶段启发式算法确定省电力物资周转库选址和配送路径。结果表明该算法能够有效降低仓储网络的总配送成本。

关键词：电力物资选址-路径问题 K-means聚类重心法自适应大邻域搜索算法

Hierarchically porous Fe/N/S/C nanospheres with high-content of Fe-Nx for enhanced ORR and Zn-air battery performance

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Green Energy & Environment 2023年第6期8卷 1693-1702页

作者： Luming Wu Ruge Zhao guo du Huan Wang Machuan Hou Wei Zhang Pingchuan Sun Tiehong Chen Institute of New Catalytic Materials Science School of Materials Science and EngineeringNankai UniversityTianjin300350China Key Laboratory of Advanced Energy Materials Chemistry(Ministry of Education) Renewable Energy Conversion and Storage CenterCollege of ChemistryNankai UniversityTianjin300071China Haihe Laboratory of Sustainable Chemical Transformations Tianjin300192China Key Laboratory of Functional Polymer Materials(MOE) College of ChemistryNankai UniversityTianjin300071China

Heteroatom-doped carbon-based transition-metal single-atom catalysts(SACs) are promising electrocatalysts for oxygen reduction reaction(ORR). Herein, with the aid of hierarchically porous silica as hard template, a facile and general melting perfusion and mesopore-confined pyrolysis method was reported to prepare single-atomic Fe/N–S-doped carbon catalyst(FeNx/NC-S) with hierarchically porous structure and well-defined morphology. The FeNx/NC-S exhibited excellent ORR activity with a half-wave potential(E_(1/2)) of 0.92 V, and a lower overpotential of 320 mV at a current density of 10 mA cm^(-2)for OER under alkaline condition. The remarkable electrocatalysis performance can be attributed to the hierarchically porous carbon nanospheres with S doping and high content of Fe-Nx sites(up to 3.7 wt% of Fe), resulting from the nano-confinement effect of the hierarchically porous silica spheres(NKM-5) during the pyrolysis process. The rechargeable Zn-air battery with FeNx/NC-S as a cathode catalyst demonstrated a superior power density of 194.5 mW cm-2charge–discharge stability. This work highlights a new avenue to design advanced SACs for efficient sustainable energy storage and conversion.

关键词： Melting perfusion Nano-confined pyrolysis Hierarchically porous High content of Fe-Nx sites Sulfur doping Oxygen reduction reaction