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Production of jet fuel intermediates from biomass platform compounds via aldol condensation reaction over iron-modified McM-41 lewis acid zeolite

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Journal of Bioresources and Bioproducts 2020年第4期5卷 256-265页

作者： Mingxue Su wenzhi Li Qiaozhi Ma Bowen Zhu Laboratory of Basic Research in Biomass conversion and Utilization Department of Thermal Science and Energy EngineeringUniversity of Science and Technology of ChinaHefei 230026China college of Materials and energy South China Agricultural UniversityGuangzhou 510642China Anhui Bengbu No.2 high school Bengbu 233000China

Liquid fuel intermediates could be produced via aldol condensation reaction between furfural or 5-hydroxymethylfurfural(HMF)and *** was found that iron-modified McM-41 zeolite can be an effective Lewis acid catalyst for c-c bond formation via aldol condensation of furfural or HMF with *** 4-(2-furyl)-3-buten-2-one and 1,5-di-2-furanyl-1,4-pentadien-3-one(FAc and F_(2)Ac),or 1,5-di-2-furanyl-1,4-pentadien-3-one and 1,5-bis[(5-hydroxlmethyl)-2-furanyl]-1,4-pentadien-3-one(HAc and H_(2)Ac),as two main condensation products of furfural with acetone or HMF with acetone,were *** 24 h at 160℃,86.9%conversion of furfural with 60.0%yield of the FAc as well as 7.5%yield of the F_(2)Ac and 88.9%conversion of the HMF with 41.1%yield of the HAc as well as 3.5%yield of the H_(2)Ac were *** furfural or HMF conversion was almost same after 24 h at 160℃,iron-modified McM-41 zeolite catalyst displayed an enhanced selectivity to condensation products of furfural with *** addition,catalysts showed an improved selectivity to the F_(2)Ac and H_(2)Ac at higher reaction *** reusability and regeneration studies showed that iron-modified McM-41 zeolite catalyst could not be reused directly,but could be regenerated by calcination in air,and the catalytic perfor-mance of regenerated catalyst was acceptable.

关键词： Biomass platform compounds Lewis acid zeolite Fuel Iron

A comparative study on characteristics of sulfur and nitrogen transformation and gaseous emission for combustion of bituminous coal and char

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carbon Resources conversion 2018年第1期1卷 86-93页

作者： Jili Hou Yue Ma Shuyuan Li wenzhi Shang a State Key Laboratory of Heavy Oil Processing China University of Petroleum-BeijingBeijing 102249PR China Shenmu Sanjiang coal chemical Industry co. Ltd.Shenmu 719300PR China

The characteristics of sulfur and nitrogen transformation and the emissions’comparison of sulfurous and nitrogenous gas were investigated using SEM,XPS,TG-FTIR and TG-gas analyzer during the combustion process of Shenmu bituminous coal(SM coal)and its *** indicated that porosity and specific surface area of char were enlarged after coal pyrolysis and a large amount of space could be provided for the oxidation reaction of various sulfur species with oxide during the combustion *** sulfur and nitrogen species of the two samples analyzed by XPS showed that,pyritic sulfur,organic sulfide sulfur,sulfone and sulfoxide sulfur in coal were partly transformed to thiophenic sulfur and sulfate sulfur in the pyrolysis of coal,and the total sulfur content in char was ***,the sulfur and nitrogen species’changes in SM coal,char and the ashes determined by XPS showed that sulfur fixation effect was enhanced in the presence of calcium oxide during *** component analysis of the gas during combustion via TG-FTIR indicated that SO2 and NO2 began to escape at 300c and reached maximum at about 1100c,by contrast,the emissions of SO2 and NO2 of char were below that of SM coal throughout the whole combustion *** wide range of TG-gas analyzer analysis revealed that the SO2 and NOx emissions of SM coal were 2.51 and 1.71 times as much as char burning,respectively.

关键词： coal char S/N combustion Transformation XPS TG-FTIR

Detection of leaf structures in close-range hyperspectral images using morphological fusion

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Geo-Spatial Information Sc.ence 2017年第4期20卷 325-332页

作者： Gladys Villegas wenzhi Liao Ronald criollo Wilfried Philips Daniel Ochoa Department of Telecommunications and Information Processing Ghent University-imec Ghent Belgium Facultad de Ingeniería en Eléctrica y computación ESPOL Polytechnic University Escuela Superior Politécnica del Litoral Guayaquil Ecuador

close-range hyperspectral images are a promising source of information in plant biology,in particular,for in vivo study of physiological *** this study,we investigate how data fusion can improve the detection of leaf elements by combining pixel reflectance and morphological *** detection of image regions associated to the leaf structures is the first step toward quantitative analysis on the physical effects that genetic manipulation,disease infections,and environmental conditions have in *** tested our fusion approach on Musa acuminata (banana) leaf images and compared its discriminant capability to similar techniques used in remote *** results demonstrate the effic.ency of our fusion approach,with significant improvements over some conventional methods.

关键词： Hyperspectral fusion morphology plant biology

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气动可变刚度弹性轴结构原理和实验分析

机床与液压 2024年第10期52卷 33-37页

作者：贾鑫耿德旭王霞许文智武广斌苟志攀彭贺北华大学机械工程学院吉林吉林132021

为解决传统柔性机器人承载能力不足的问题,结合颗粒堵塞原理,提出一种正压驱动变刚度弹性轴。分析此弹性轴的变刚度机制,基于变刚度弹性轴样机搭建实验平台,通过实验分析不同因素对弹性轴刚度影响。实验结果表明:弹性轴填充钢珠和无填... 详细信息

为解决传统柔性机器人承载能力不足的问题,结合颗粒堵塞原理,提出一种正压驱动变刚度弹性轴。分析此弹性轴的变刚度机制,基于变刚度弹性轴样机搭建实验平台,通过实验分析不同因素对弹性轴刚度影响。实验结果表明:弹性轴填充钢珠和无填充物对比,弹性轴刚度提升2.1倍;弹性轴环形密闭腔体越大,填充颗粒越多,弹性轴刚度越强;内气囊管径越大,弹性轴刚度越强;在充入气压分别为0、0.3 MPa时,填充经磨砂处理的钢珠弹性轴的刚度提高3倍,填充ABS不规则形状弹性轴的刚度提高4.3倍。

关键词：弹性轴变刚度颗粒阻塞

谷氨酸铁螯合物对缺铁性贫血小鼠的补铁效果评价

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河北大学学报（自然科学版） 2024年第4期44卷 365-372页

作者：任梽源刘新硕陆时金杨文智李海鹰河北大学药学院河北省药物质量分析控制重点实验室河北保定071002 中国人民解放军联勤保障部队第九六七医院药剂科辽宁大连116021

为评价自制谷氨酸铁(Glu-Fe(Ⅲ))和谷氨酸亚铁(Glu-Fe(Ⅱ))的补铁效果,采用低铁饲料联合放血法建立缺铁性贫血(IDA)小鼠模型,并将IDA小鼠随机分成硫酸亚铁组、市售右旋糖酐铁组、Glu-Fe(Ⅱ)组和Glu-Fe(Ⅲ)组,分别灌胃给予同等铁剂量的... 详细信息

为评价自制谷氨酸铁(Glu-Fe(Ⅲ))和谷氨酸亚铁(Glu-Fe(Ⅱ))的补铁效果,采用低铁饲料联合放血法建立缺铁性贫血(IDA)小鼠模型,并将IDA小鼠随机分成硫酸亚铁组、市售右旋糖酐铁组、Glu-Fe(Ⅱ)组和Glu-Fe(Ⅲ)组,分别灌胃给予同等铁剂量的不同补铁剂4周,并以IDA小鼠为阴性对照、正常小鼠为空白对照组进行比较.用全自动血液分析仪监测小鼠血中血红蛋白(HGB)、红细胞(RBc)和血细胞比容(HcT)变化,采用血清铁(SI)、总铁结合力(TIBc)和转铁蛋白(TRF)试剂盒测定小鼠体内铁状况并测定小鼠组织(心、肝、脾和肾)铁含量,利用总超氧化物歧化酶(SOD)、过氧化氢酶(cAT)和丙二醛(MDA)试剂盒检测各种补铁剂对小鼠体内抗氧化的影响.结果显示:IDA小鼠建模成功,Glu-Fe(Ⅲ)和Glu-Fe(Ⅱ)可提高IDA小鼠的HGB、RBc和HcT值,降低TIBc和TRF水平并提升SI含量,而Glu-Fe(Ⅲ)补铁剂效果更佳.此外,相比硫酸亚铁和右旋糖酐铁,饲喂Glu-Fe(Ⅲ)在改善IDA小鼠内脏器官(心、脾和肾)肿大、促进肝恢复、提升肝脾储铁、清除组织活性氧(ROS)且增强抗氧化活性等方面表现更佳.

关键词：谷氨酸亚铁螯合物谷氨酸铁螯合物缺铁性贫血补铁剂

constructing supramolecular polymers from phototrigger containing monomer

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chinese chemical Letters 2018年第11期29卷 1621-1624页

作者： Xiuli Zheng Qi Miao wenzhi Wang Da-Hui Qu Key Laboratory for Advanced Materials and Institute of Fine chemicals School of Chemistry and Molecular EngineeringEast China University of Science &Technology

A new type of photo-induced supramolecular polymer was fabricated by host-guest interaction from a phototrigger containing building block. A dibenzo-24-crown-8 （DB24c8） macrocycle and dibenzylammonium （DBA） site containing linear monomer was designed and synthesized. The coumarin, as a photocleavable protector, was introduced to the terminal of the monomer. When exposed to the UV light, the coumarin unit would be cleavaged and the monomer without terminal coumarin can self-assemble into supramolecular polymers via the host-guest interaction between DB24c8 moieties and DBA units. Increasing the concentration of the monomer, the supramolecular polymers will convert to supramolecular organogel by cross-linking with each other.

关键词： Supramolecular polymer Host-guest recognition Photo-responsive crown ether

Sensitivity analysis of the SWAP(Soil-Water-Atmosphere-Plant)model under different nitrogen applications and root distributions in saline soils

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Pedosphere 2021年第5期31卷 807-821页

作者： Guoqing LEI wenzhi ZenG Yonghua JIANG chang AO Jingwei WU Jiesheng HUANG State Key Laboratory of Water Resources and Hydropower engineering Sc.ence Wuhan UniversityWuhan 430072(China) School of Remote Sensing and Information engineering Wuhan UniversityWuhan 430079(China) State Key Laboratory of Information engineering in Surveying Mapping and Remote SensingWuhan UniversityWuhan 430079(China)

Sensitivity analysis is important for determining the parameters in the model calibration *** our study,a variance-based global sensitivity analysis(extended Fourier amplitude sensitivity test,EFAST)was applied to an agro-hydrological model(the SWAP(Soil-Water-Atmosphere-Plant model)model).The sensitivities of 20 parameters belonging to 4 categories(soil hydraulics,solute transport,root water uptake,and environmental stresses)for the simulated accumulated transpiration,dry matter(DM),and yield of sunflowers were analyzed under three nitrogen application rates(N1,N2,and N3),four salinity levels(S1,S2,S3,and S4),and three root distributions(R1,R2,and R3).The results indicated that for predominantly loamy soils,the high-impact parameters for accumulated transpiration,DM,and yield were the soil hydraulic parameters(αand n),critical stress index for compensatory root water uptake(ωc),the salt level at which salt stress starts(Pi),the decline of root water uptake above Pi(SSF),residual water content(θr),saturated water content(θs),and relative uptake of solutes by roots(TScF).We also found that nitrogen application did not change the order of the parameter impacts on accumulated transpiration,DM,and ***,TScF replacedαas the highest-impact parameter for the accumulated transpiration,DM,and yield at high salinity levels(S2 and S3).Furthermore,αwas also the highest-impact parameter for DM and yield under different root distributions,but the highest-impact parameters for transpiration wereωc,α,andθs under R1,R2,and R3,*** application could be neglected when considering the interactive effects of nitrogen application,salinity level,and root distribution on the transpiration,DM,and ***,the mean values and uncertainties of the transpiration,DM,and yield were similar in all scenarios,except S3,which showed a sharp decrease in the mean *** suggest determining the above eight parameters(α,n,ωc,Pi,SSF,θr,θs,and TScF)and the sat

关键词： accumulated transpiration agro-hydrological model dry matter hydraulic parameter sunflower yield

Influence of Metallic Modification on Ethylbenzene Dealkylation over ZSM-5 Zeolites

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中国化学:英文版 2015年第2期33卷 247-252页

作者： chao Hu Junhui Li wenzhi Jia Min Liu Zhixian Hao Zhirong Zhu Department of chemistry Tongji UniversityShanghai 200092China

A series of metal-modified HZSM-5 catalysts were prepared by impregnation and were used for ethylbenzene dealkylation of the mixed c8 aromatics(ethylbenzene,m-xylene and o-xylene).The effects of different supported metals(Pt,Pd,Ni,Mo)on catalytic performance,including reaction conditions,were *** physicochemical properties of catalysts were characterized by means of XRD,BET,TEM and NH_(3)-*** results showed that metallic modification obviously increased the ethylbenzene conversion and reduced the coke deposition,greatly improving the catalyst *** distinction of ethylbenzene conversion depended on the interaction between hydrogenation reactivity and acidic cracking of bifunctional metal-modified *** with Pt and Ni,Pd and Mo were easier to disperse into HZSM-5 micropores during loading *** acidic density of different metal-modified HZSM-5 declined in the following order:HZSM-5>Pt/HZSM-5>Pd/HZSM-5>Ni/HZSM-5>Mo/*** activity of ethylene hydrogenation decreased with Pt/HZSM-5>Pd/HZSM-5>Ni/HZSM-5>Mo/*** comparison,Pd/HZSM-5 showed the best catalytic performance with both high activity and high selectivity,with less cracking loss of m-xylene and ***,the following reaction conditions were found to be preferable for ethylbenzene dealkylation over Pd/HZSM-5:340℃,1.5 MPa H2,WHSV 4 h^(−1),H_(2)/c84 mol/mol.

关键词： ethylbenzene dealkylation zeolites palladium

Bonding VSe2 ultrafine nanocrystals on graphene toward advanced lithium-sulfur batterie

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Nano Research 2020年第10期13卷 2673-2682页

作者： wenzhi Tian Baojuan Xi Yu Gu Qiang Fu Zhenyu Feng Jinkui Feng Shenglin Xiong Key Laboratory of clloid and Interface chemistry Ministry of EducationSchool of Chemistry and Chemical Engineringand State Key Laboratory of Crystal MaterialsShandong UniversityJinan 250100China Key Laboratory for Liquid Solid Structural Evolution&Processing of Materials(Ministry of Education) School of Materials Science and EngineeringShandong UniversityJinan 250061China

Lithium–sulfur batteries have been attracting considerable research attention due to their high energy densities and low costs. However, one of their main challenges is the undesired shuttling of polysulfides, causing rapid capacity degradation. Herein, we report the first example of sulfiphilic VSe2 ultrafine nanocrystals immobilized on nitrogen-doped graphene to modify the battery separator for alleviating the shuttling problem. VSe2 nanocrystals provide numerous active sites for chemisorption of polysulfides as well as benefit the nucleation and growth of Li2S. Furthermore, the kinetic reactions are accelerated which is confirmed by higher exchange current density and higher lithium ion diffusion coeffic.ent. And the first-principles calculations further show that the exposed sulfiphilic planes of VSe2 boost the redox of Li2S. When used as separators within the lithium sulfur batteries, the cell indicates greatly enhanced electrochemical performances with excellent long cycling stability and exceptional rate capability up to 8 c. Moreover, it delivers a higher areal capacity of 4.04 mAh·cm^−2 as well as superior cycling stability with sulfur areal loading up to 6.1 mg·cm^−2. The present strategy can encourage us in engineering novel multifunctional separators for energy-storage devices.

关键词： sulfiphilic VSe2 lithium–sulfur batteries nucleation and growth of Li2S polysulfide electrocatalysis shuttle effect