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Formic acid fractionation towards highly efficient cellulose-derived PdAg bimetallic catalyst for H_(2) evolution

Green Energy & Environment 2022年第1期7卷 172-183页

作者： Yanyan Yu huanghui Xu Hongfei Yu Lihong Hu Yun Liu Beijing Key Laboratory of Bioprocess College of Life Science and TechnologyBeijing University of Chemical TechnologyBeijing100029China Beijing Zest Bridge Media Technology Inc. Beijing100176China Institute of Chemical Industry of Forest Products Chinese Academy of ForestryNanjing210042China

The present work,in which cellulose isolated from formic acid fractionation(FAC)is decorated with polyetherimide(PEI)to attain highly efficient cellulose-derived PdAgbimetallic catalyst(PdAg-PEI-FAC),has been investigated,and the catalyst properties are characterized by XRD,XPS,BET,ICP-AES and HAADF-STEM.The as-obtained Pd_(3.75)Ag_(3.75)-PEI-FAC exhibits excellent catalytic performance for H_(2)evolution from a sodium formate-free formic acid(FA)aqueous medium at ambient temperature and the turnover frequency(TOF)reaches a high value of 2875 h^(-1)which is superior to most of the previously reported Pd-based heterogeneous catalysts supported on a carbon matrix in the literature.The remarkable catalytic activities of PdAg-PEI-FAC result from high dispersion Pd and synergistic effects between the PdAg bimetallic system.Furthermore,the amide(-NH)group in PEI coated on cellulose acting as a proton scavenger efficiently improves the catalytic property of catalyst.In addition,the critical factors affecting H;release,such as FA concentration,reaction temperature,PdAg compositions and support matrix type,are also evaluated.Based on the experimental results,the probable three-step mechanism of H_(2)evolution from FA over Pd_(3.75)Ag_(3.75)-PEI-FAC is proposed.In the end,the activation energy(Ea)of Pd_(3.75)Ag_(3.75)-PEI-FAC catalyst is calculated to 53.97 kJ mol^(-1),and this catalyst shows unique robustness and satisfactory re-usability with no loss of catalytic activity after five recycles.The findings in this work provide a novel routine from lignocellulose fractionation towards cellulose-derived catalyst for H_(2)evolution.

关键词： Formic acid fractionation Cellulose modification Cellulose-derived PdAg bimetallic catalyst Hydrogen generation Mechanism

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Auto-thermal reforming of acetic acid for hydrogen production by Zn_(x)Ni_(y)CrO_(m±δ) catalysts:Effect of Cr promoted Ni-Zn intermetallic compound

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Chinese Journal of Chemical Engineering 2022年第3期35卷 216-221页

作者： Xuanyi Jia Xiaomin hu Qiao Wang Baiquan Chen Xingyue Xie Lihong Huang Department of Chemical and Pharmaceutical Engineering Chengdu University of TechnologyChengdu 610059China Richard G.Lugar Center for Renewable Energy Indiana University-Purdue UniversityIndianapolisIN 46202United States

A series of Zn_(x)Ni_(y)CrO_(m±δ)catalysts were synthesized via a typical co-precipitation method,in which Zn-Cr layered double hydroxides(LDHs)were found and Ni-Zn intermetallic compound(IMC)was formed after reduction in hydrogen.During auto-thermal reforming(ATR)of acetic acid(HAc),the Ni-Zn IMC was transformed into Ni/(amorphous-ZnO)-ZnCr_(2)O_(4) species with uniformed distribution and appropriate interaction within these Ni-Zn-Cr-O species;besides,the adsorbed oxygen promoted the activation and transfer of oxygen species;therefore,deactivation by oxidation,sintering and coking was inhibited.And the optimized Zn_(2.37)Ni_(0.63)CrO_(4.5±δ)catalyst presented high activity and stability in a 45-h ATR test with HAc conversion near 100%and hydrogen yield at 2.7 mol-H_(2)/mol-HAc,showing potential for hydrogen production via ATR of HAc.

关键词： Ni-Zn intermetallic compound Zn-Cr layered double hydroxide Hydrogen production Auto-thermal reforming Biomass Catalysis

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Global sensitivity and uncertainty analysis of the VIP ecosystem model with an expanded soil nitrogen module for winter wheat-summer maize rotation system in the North China Plain

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Pedosphere 2021年第5期31卷 822-838页

作者： lihong HE Xingguo MO Shi hu Suxia LIU Key Laboratory of Water Cycle and Related Land Surface Processes Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101(China) College of Resources and Environment University of Chinese Academy of SciencesBeijing 100049(China) Sino-Danish Center University of Chinese Academy of SciencesBeijing 100049(China)

Accurately simulating the soil nitrogen(N)cycle is crucial for assessing food security and resource utilization efficiency.The accuracy of model predictions relies heavily on model parameterization.The sensitivity and uncertainty of the simulations of soil N cycle of winter wheat-summer maize rotation system in the North China Plain(NCP)to the parameters were analyzed.First,the N module in the Vegetation Interface Processes(VIP)model was expanded to capture the dynamics of soil N cycle calibrated with field measurements in three ecological stations from 2000 to 2015.Second,the Morris and Sobol algorithms were adopted to identify the sensitive parameters that impact soil nitrate stock,denitrification rate,and ammonia volatilization rate.Finally,the shuffled complex evolution developed at the University of Arizona(SCE-UA)algorithm was used to optimize the selected sensitive parameters to improve prediction accuracy.The results showed that the sensitive parameters related to soil nitrate stock included the potential nitrification rate,Michaelis constant,microbial C/N ratio,and slow humus C/N ratio,the sensitive parameters related to denitrification rate were the potential denitrification rate,Michaelis constant,and N2 O production rate,and the sensitive parameters related to ammonia volatilization rate included the coefficient of ammonia volatilization exchange and potential nitrification rate.Based on the optimized parameters,prediction efficiency was notably increased with the highest coefficient of determination being approximately 0.8.Moreover,the average relative interval length at the 95% confidence level for soil nitrate stock,denitrification rate,and ammonia volatilization rate were 11.92,0.008,and 4.26,respectively,and the percentages of coverage of the measured values in the 95% confidence interval were 68%,86%,and 92%,respectively.By identifying sensitive parameters related to soil N,the expanded VIP model optimized by the SCE-UA algorithm can effectively simulate the dynamics of soil nitrate stock,denitr

关键词： ammonia volatilization denitrification rate global sensitivity analyses shuffled complex evolution developed at the University of Arizona(SCE-UA)algorithm vegetation interface processes model

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Preparation and Characterization of Tung Oil Toughened Modified Phenolic Foams with Enhanced Mechanical Properties and Smoke Suppression

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Journal of Renewable Materials 2020年第5期8卷 535-547页

作者： Fei Song Puyou Jia Caiying Bo Xiaoli Ren Lihong Hu Yonghong Zhou Institute of Chemical Industry of Forest Products Chinese Academy of ForestryNational Engineering Laboratory for Biomass Chemical UtilizationCo-Innovation Center of Efficient Processing and Utilization of Forest ResourcesKey Laboratory of Chemical Engineering of Forest ProductsNational Forestry and Grassland AdministrationKey Laboratory of Biomass Energy and MaterialsNanjing210042China Nanjing Forestry University Nanjing210037China

In this study,we prepared a series of tung oil phenolic foams(TPF)by a one-pot method.The FT-IR and 1H NMR spectra confirm the successful Friedel-Crafts grafting of phenol to the long-chain alkyl group in tung oil.Modified TPFs exhibit enhanced mechanical properties,including compressive and flexural strengths of up to 0.278±0.036 MPa and 0.450±0.017 MPa,respectively,which represent increases of 68.75%and 86.72%over those of pure phenolic foam(PF).SEM spectra reveal the TPF microstructure to have uniform hexagonal cell morphology,narrower cell size distribution,and smaller mean cell size,suggesting enhanced mechanical properties.The TPF total smoke release decreased by 74.23%,indicating that the long alkyl chain significantly improves smoke suppression of the combusting foam.However,due to the flammability of the alkyl chains,the TPF limiting oxygen index decreases with increasing tung oil content.Moreover,TPF exhibits reduced thermal stability and high-temperature charring rate,elevated peak and mean heat release rates,and higher total heat release compared with pure PF.Therefore,future research will focus on the use of tung oil modified flame retardant to provide more robust phenolic foams.

关键词： Tung oil Friedel-Craft reaction phenolic foams mechanical properties smoke suppression

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Motors drive high demand for rare earths

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China Rare Earth Information 2022年第1期28卷 24-26页

作者： YANG lihong hu Bo huajin Securities

1.Rare earths become the driving materials of low-carbon and intelligent era(1)Wide applications of rare earths in low-carbon and intelligent industries Low carbonization and industrial intelligence are two of the most important power driving the economy growth of China and the world today.And rare earths are the core materials for these two driving forces.

关键词： earths rare driving

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Study on Toughening Phenolic Foams in Phosphorus-Containing Tung Oil-Based Derivatives

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Journal of Renewable Materials 2019年第10期7卷 1011-1021页

作者： Fei Song Puyou Jia Yanan Xiao Caiying Bo Lihong Hu Yonghong Zhou Institute of Chemical Industry of Forest Products Chinese Academy of Forestry(CAF)National Engineering Laboratory for Biomass Chemical UtilizationCo-Innovation Center of Efficient Processing and Utilization of Forest ResourcesKey Laboratory of Chemical Engineering of Forest ProductsNational Forestry and Grassland AdministrationKey Laboratory of Biomass Energy and MaterialsNanjing210042China School of Petroleum and Chemical Engineering Dalian University of TechnologyDalian124221China

Phenolic foams(PFs)as thermal insulation material with outstanding flame retardancy are required to match society’s ever-expanding safety expectations;however,a trade-off exists between flame retardancy and toughness.Here,for the first time,we synthesized a novel reactive phosphorus-containing tung-oil-based derivative and used it to toughen PF,resulting in PFs with a combination of excellent mechanical properties and flame retardancy.Compared with pure PF,the modified PFs exhibit enhanced mechanical properties,with specific compressive and flexural strengths as high as 5.67 MPa and 12.46 MPa,which represent increases of 90.67%and 178.7%over those of pure PF,respectively.Meanwhile,the limiting oxygen index(LOI)values of the modified PFs are improved as much as 40.83%.Scanning electron microscopy micrographs show that the microstructure of the modified PFs is better than that of pure PF,with a more uniform cell morphology,a narrower pore size distribution range,and a smaller average pore size,all of which are beneficial to the foam’s mechanical properties.This study provides a scientific paradigm for the development of advanced PFs based on renewable biological resources.

关键词： Tung oil phenolic foams toughen mechanical properties LOI

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Lonicerin targets EZH2 to alleviate ulcerative colitis by autophagy-mediated NLRP3 inflammasome inactivation

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Acta Pharmaceutica Sinica B 2021年第9期11卷 2880-2899页

作者： Qi Lv Yao Xing Jian Liu Dong Dong Yue Liu Hongzhi Qiao Yinan Zhang Lihong Hu Jiangsu Key Laboratory for Functional Substance of Chinese Medicine Stake Key Laboratory Cultivation Base for TCM Quality and EfficacySchool of PharmacyNanjing University of Chinese MedicineNanjing 210023China

Aberrant activation of NLRP3 inflammasome in colonic macrophages strongly associates with the occurrence and progression of ulcerative colitis.Although targeting NLRP3 inflammasome has been considered to be a potential therapy,the underlying mechanism through which pathway the intestinal inflammation is modulated remains controversial.By focusing on the flavonoid lonicerin,one of the most abundant constituents existed in a long historical anti-inflammatory and anti-infectious herb Lonicera japonica Thunb.,here we report its therapeutic effect on intestinal inflammation by binding directly to enhancer of zeste homolog 2(EZH2)histone methyltransferase.EZH2-mediated modification of H3 K27 me3 promotes the expression of autophagy-related protein 5,which in turn leads to enhanced autophagy and accelerates autolysosome-mediated NLRP3 degradation.Mutations of EZH2 residues(His 129 and Arg685)indicated by the dynamic simulation study have found to greatly diminish the protective effect of lonicerin.More importantly,in vivo studies verify that lonicerin dose-dependently disrupts the NLRP3-ASC-pro-caspase-1 complex assembly and alleviates colitis,which is compromised by administration of EZH2 overexpression plasmid.Thus,these findings together put forth the stage for further considering lonicerin as an anti-inflammatory epigenetic agent and suggesting EZH2/ATG5/NLRP3 axis may serve as a novel strategy to prevent ulcerative colitis as well as other inflammatory diseases.

关键词： Lonicerin Colitis NLRP3 inflammasome Autophagy EZH2

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Transition-metal-catalyzed switchable divergent cycloaddition of para-quinone methides and vinylethylene carbonates:Access to different sized medium-sized heterocycles

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Chinese Chemical Letters 2022年第10期33卷 4549-4558页

作者： Junwei Wang Lei Zhao Chen Zhu Ben Ma Xiaolong Xie Jian Liu Shiyun He Magnus Rueping Kun Zhao Lihong Hu Jiangsu Key Laboratory for Functional Substances of Chinese Medicine School of PharmacyNanjing University of Chinese MedicineNanjing 210023China KAUST Catalysis Center(KCC) King Abdullah University of Science and Technology(KAUST)Thuwal 23955-6900Saudi Arabia Chemistry Key Laboratory of Chemical BiologySchool of PharmacyCheeloo College of MedicineShandong UniversityJi'nan 250012China

Divergent synthesis of medium-sized rings with controllable ring sizes represents a longstanding challenge in organic synthesis.Herein,we developed a transition-metal-catalyzed switchable divergent cycloaddition of para-quinone methides and vinylethylene carbonates by controlling the steric hindrance of substituent.Different from reported alkoxide-triggered annulations,this process undergoes a regiodivergent allylation of para-quinone methides followed by 1,6-addition reaction,providing a new route to selectively synthesize seven-to ten-membered nitrogen-containing heterocycles in high yields with excellent regioselectivities.This protocol features a broad substrate scope,wide functional group tolerance as well as operational simplicity.The reaction mechanism was investigated by conducting a series of control experiments as well as DFT calculations and the origins of the regioselectivities of the cycloaddition process were rationalized.

关键词： Medium-sized rings Divergent cycloaddition Regioselectivity para-Quinone methides Vinylethylene carbonates

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White Laser Realized via Synergic Second-and Third-Order Nonlinearities

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Research 2021年第1期2021卷 8-20页

作者： Baoqin Chen lihong Hong Chenyang hu Zhiyuan Li School of Physics and Optoelectronics South China University of TechnologyGuangzhou 510641China Guangdong Jingqi Laser Technology Corporation Limited SongshanhuDongguan 523808China

White laser with balanced performance of broad bandwidth,high average and peak power,large pulse energy,high spatial and temporal coherence,controllable spectrum profile,and overall chroma are highly desirable in various fields of modern science.Here,for the first time,we report an innovative scheme of harnessing the synergic action of both the second-order nonlinearity(2^(nd)-NL)and the third-order nonlinearity(3^(rd)-NL)in a single chirped periodically poled lithium niobate(CPPLN)nonlinear photonic crystal driven by a high-peak-power near-infrared(NIR)(central wavelength~1400 nm,energy~100μJ per pulse)femtosecond pump laser to produce visible to near infrared(vis-NIR,400-900 nm)supercontinuum white laser.The CPPLN involves a series of reciprocal-lattice bands that can be exploited to support quasiphase matching for simultaneous broadband second-and third-harmonic generations(SHG and THG)with considerable conversion efficiency.Due to the remarkable 3rdNL which is due to the high energy density of the pump,SHG and THG laser pulses will induce significant spectral broadening in them and eventually generate bright vis-NIR white laser with high conversion efficiency up to 30%.Moreover,the spectral profile and overall chroma of output white laser can be widely modulated by adjusting the pump laser intensity,wavelength,and polarization.Our work indicates that one can deeply engineer the synergic and collective action of 2^(nd)-NL and 3^(rd)-NL in nonlinear crystals to accomplish high peak power,ultrabroadband vis-NIR white laser and hopefully realize the even greater but much more challenging dream of ultraviolet-visible-infrared full-spectrum laser.

关键词： pump visible nonlinearity

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身体是修行的道场:印度女性导演的身体书写与身份自塑

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当代电影 2022年第11期 139-145页

作者：胡黎红中国传媒大学戏剧影视学院

印度女性导演在近十年的创作中凸显出醒目的身体转向,其身体书写亦呈现出鲜明的话语特征:审美取向上,通过焦点转换实现了“破”与“立”;文化意旨上,通过欲望书写的重返现场指向对权力规训的批判与翻转;人文哲思上,对深具现代性的身心... 详细信息

印度女性导演在近十年的创作中凸显出醒目的身体转向,其身体书写亦呈现出鲜明的话语特征:审美取向上,通过焦点转换实现了“破”与“立”;文化意旨上,通过欲望书写的重返现场指向对权力规训的批判与翻转;人文哲思上,对深具现代性的身心对峙、灵肉分离困境给予了关怀。以身体作为修行道场,女性导演致力于达成女性创作者、受印度文明灌育的创作者、面向世界的创作者等多重身份的自塑。文本和超文本互相阐释、叠加增值,完成了一场从客体到主体、从个体到群体、从身体到身份的涉渡之旅。

关键词：印度女性身体身份

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