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Effect of hydrogenation of liquefied heavy oil on direct coal liquefaction

FUEL 2017年 194卷 291-296页

作者： Shan Xiangen Shu Geping Li Kejian zhang xuwen Wang Hongxue Cao Xueping Jiang Hongbo Weng Huixin East China Univ Sci & Technol Res Inst Petr Proc Shanghai 200237 Peoples R China Natl Engn Lab Direct Coal Liquefact Shanghai 201108 Peoples R China

The effect of hydrotreatment of liquefied heavy oil on direct coal liquefaction (DCL) was studied by hydrogenating the liquefied heavy oil (initial boiling point greater than 320 degrees C) in a 30 ml continuous hydrogenation apparatus at operating conditions of pressure (P) 13-19 MPa, temperature (T) 360-400 degrees C, liquid space velocity (LHSV) 0.6-1.4 h(-1). After hydrogenation, the properties and hydrocarbon composition of liquefied heavy oil were regulated, leading to the enhancement of hydrogen donating ability and 5.6% increase in oil yield of DCL as compared with non-hydrogenated raw oil. Based on the results, a new method of preparing recycle solvent for direct coal liquefaction by mixing hydrogenated heavy oil and un-hydrogenated middle oil in a suitable proportion was proposed, which has been verified to be effective and efficient to increase oil yield. (C) 2017 Elsevier Ltd. All rights reserved.

关键词： Direct coal liquefaction Hydrogenation Liquefied product Hydrogenated oil Hydrogen-donating ability

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Direct Arylation Polycondensation toward Water/Alcohol-Soluble Conjugated Polymers: Influence of Side Chain Functional Groups

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ACS MACRO LETTERS 2021年第4期10卷 419-425页

作者： Zhao, Bowen Liang, Ziqi zhang, Ying Sui, Ying Shi, Yibo zhang, xuwen Li, Miaomiao Deng, Yunfeng Geng, Yanhou Tianjin Univ Sch Mat Sci & Engn Tianjin 300072 Peoples R China Tianjin Univ Tianjin Key Lab Mol Optoelect Sci Tianjin 300072 Peoples R China Tianjin Univ Joint Sch Natl Univ Singapore & Tianjin Univ Int Campus Fuzhou 350207 Peoples R China

Direct arylation of 2,7-dibromofluorene with n-octyl, 6-diethoxylphosphorylhexyl, 6-(N,N-diethylamino)hexyl or 6-bromohexyl side chains and 1,2,4,5-tetrafluorobenzene (TFB) were conducted to investigate the effect of side chain functional groups on the coupling, and the resulting TFB-substituted fluorene derivatives were used as C-H monomers for the synthesis of water/alcohol soluble conjugated polymers (WSCPs) by direct arylation polycondensation (DArP). The direct arylation and DArP of the monomers carrying phosphonate and amino groups went on smoothly in typical DArP conditions, that is, Pd(OAc)(2)/(PBu2Me)-Bu-t-HBF4/base/DMAc and Pd-2(dba)(3)center dot CHCl3/P(o-MeOPh)(3)/pivalic acid/base/THF, and high molecular weight polymers with these groups were successfully synthesized. However, for fluorenemonomers with bromohexyl side chains, the target products could not be obtained from the above conditions but could be prepared in the absence of carboxylic acid additives in low polar solvents. With the above DArP-made polymers as cathode interfacial layers, high performance organic solar cells (OSCs) were successfully fabricated.

关键词： Monomers Organic reactions Organophosphorus compounds Condensation Polymers

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C^1;1-RECTIFIABILITY AND HEINTZE-KARCHER INEQUALITY ON Sⁿ⁺¹

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ESAIM-CONTROL OPTIMISATION AND CALCULUS OF VARIATIONS 2023年 29卷

作者： zhang, xuwen Xiamen Univ Sch Math Sci Xiamen 361005 Peoples R China Goethe Univ Inst Math D-60325 Frankfurt Germany

In this paper, by isometrically embedding (Sn+1, gS(n+1)) into Rn+2, and using nonlinear analysis on the codimension-2 graphs, we will show that the level-sets of the distance function from the boundary of any open se... 详细信息

关键词： Level-sets of distance function C-1 1 -rectifiability Heintze-Harcher-type inequality

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Diketopyrrolopyrrole-based conjugated polymers synthesized by direct arylation polycondensation for anisole-processed high mobility organic thin-film transistors

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JOURNAL OF MATERIALS CHEMISTRY C 2022年第7期10卷 2616-2622页

作者： Sui, Ying Wang, Zhongli Bai, Junhua Shi, Yibo zhang, xuwen Deng, Yunfeng Han, Yang Geng, Yanhou Tianjin Univ Sch Mat Sci & Engn Tianjin 300072 Peoples R China Tianjin Univ Tianjin Key Lab Mol Optoelectmn Sci Tianjin 300072 Peoples R China Tianjin Chengjian Univ Sch Mat Sci & Engn Tianjin 300384 Peoples R China Tianjin Univ Joint Sch Natl Univ Singapore & Tianjin Univ Int Campus Fuzhou 350207 Peoples R China

Two conjugated polymers (CPs) Fu-F and Fu-Cl that are soluble in a green solvent anisole were successfully synthesized via direct arylation polycondensation (DArP) using a furan-flanked diketopyrrolopyrrole (DPP) derivative (FDPP-Br) as the C-Br monomer and (E)-1,2-bis(3,4-difluorothien-2-yl)ethene (4FTVT) or (E)-1,2-bis(3,4-dichlorothien-2-yl)ethene (4ClTVT) as the C-H monomer. With anisole as the processing solvent and polyethylenimine ethoxylated (PEIE) as the electrode modification layer, n-type organic thin-film transistors (OTFTs) of the polymers were fabricated via bar-coating. The electron mobility (mu(e)) of the devices based on Fu-Cl was only in the magnitude of 10(-2) cm(2) V-1 s(-1), owing to the unfavoured fine granular film morphology. In contrast, Fu-F films showed fibre-like morphology with the polymer chains aligned along the bar-coating direction, which is favourable for the charge transport in OTFTs. Therefore, Fu-F delivered much better device performance with the mu(e) of up to 2.79 cm(2) V-1 s(-1). Our study demonstrates that green solvent processed high mobility CPs can be synthesized by DArP, an emerging eco-friendly protocol for the synthesis of CPs.

关键词： Conjugated polymers

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Prediction model for coal chemical wastewater quality after catalytic ozonation process treatment based on deep learning algorithm: Performance evaluation and model comparisons

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PROCESS SAFETY AND ENVIRONMENTAL PROTECTION 2025年 197卷

作者： Qin, Yihe Yuan, Run zhang, Xuewei He, xuwen Dongguan Univ Technol Sch Environm & Civil Engn Dongguan 523808 Peoples R China Tianjin Univ Sch Earth Syst Sci Tianjin 300072 Peoples R China China Univ Min & Technol Sch Chem & Environm Engn Beijing 100083 Peoples R China

In this study, we tested different models for predicting the effluent water quality of coal chemical wastewater treated by the catalytic ozonation process. The optimal model was further modified using the norm feature vector selection methods and intelligent algorithms. The average removal amount and average removal rate of COD in coal chemical wastewater treated by catalytic ozonation process were 223.62 mg/L and 57.98 %, respectively. AAO-pH, AAO-ammonia nitrogen, AAO-total phosphorus, AAO-COD, AAO-total phenol, SST-COD, SST-total phenol, and SST-turbidity were inputs for each model, while the catalytic ozonation-COD was used as the output for each model. We collected 500 samples of one year for the training, validation, and testing of various models. Compared to other models, the RF model had better predictive performance. Additionally, L1 method had a stronger optimization ability for the RF model than L2 method. Compared with BOA and SSA, IGWO had a larger contribution to improving the predictive ability. The L1-RF-IGWO model showed the best predictive ability (test set R2 of 0.8717). The present results can aid coal chemical plants achieve data-driven management of water quality prediction and monitoring, providing ideas for the construction of models for predicting water quality in engineering.

关键词： Predictive model Water quality analysis Coal chemical wastewater Catalytic ozonation

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Organocatalytic Enantioselective Friedel- Crafts Reaction of 1-Naphthols with Isatins and an Unexpected Spontaneous Dehydration Process

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ASIAN JOURNAL OF ORGANIC CHEMISTRY 2014年第4期3卷 480-486页

作者： Wu, Deyan zhang, xuwen Xu, Yong Xue, Yingfei Li, Jian Wang, Wei Zhu, Jin E China Univ Sci & Technol Shanghai Key Lab New Drug Design Sch Pharm Shanghai 200237 Peoples R China Humanwell Healthcare Grp Co Ltd Wuhan 430075 Hubei Peoples R China Univ New Mexico Dept Chem & Chem Biol Albuquerque NM 87131 USA

An organocatalytic enantioselective Friedel-Crafts alkylation of 1-naphthols with isatins has been developed. The process is catalyzed by a simple cinchona alkaloid derived thiourea and gives biologically interesting, enantioenriched 3-(naphthalen-2-yl)-3-hydroxy-2-oxindoles in moderate to good yields of 42-83% and with good to high enantioselectivity of up to 94% ee. Furthermore, an unexpected intramolecular dehydration reaction proceeds spontaneously with 4-substituted 1-naphthols to offer structurally different ketone oxindoles.

关键词： Friedel-Crafts alkylation isatins naphthols organocatalysis oxindoles

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Thienoisoindigo-Based Conjugated Polymers Synthesized by Direct Arylation Polycondensation

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MACROMOLECULAR RAPID COMMUNICATIONS 2024年第1期45卷 2300245-2300245页

作者： Wang, Pai Xu, Chenhui zhang, xuwen Shi, Yibo Wang, Cheng Han, Yang Deng, Yunfeng Geng, Yanhou Tianjin Univ Sch Mat Sci & Engn Tianjin 300072 Peoples R China Tianjin Univ Tianjin Key Lab Mol Optoelect Sci Tianjin 300072 Peoples R China Collaborat Innovat Ctr Chem Sci & Engn Tianjin Tianjin 300072 Peoples R China Tianjin Univ Joint Sch Natl Univ Singapore & Tianjin Univ Int Campus Fuzhou 350207 Peoples R China

A series of thienoisoindigo (TIG)-based conjugated polymers (CPs) with high molecular weights are synthesized by direct arylation polycondensation (DArP) by using TIG derivatives as C-Br monomer and multi-halogenated thiophene derivatives, i.e., (E)-1,2-bis(3,4-difluorothien-2-yl)ethene (4FTVT), (E)-1,2-bis(3,4-dichlorothien-2-yl)ethene (4ClTVT), 3,3',4,4'-tetrafluoro-2,2'-bithiophene (4FBT), and 3,3',4,4'-tetrachloro-2,2'-bithiophene (4ClBT), as C-H monomers. Density functional theory (DFT) calculations reveal the high selectivity between alpha-C-H bonds in 4FTVT, 4ClTVT, 4FBT, and 4ClBT and beta-C-H bonds in TIG C-Br monomer. All four resulting CPs exhibit low optical bandgaps of ca. 1.20 eV and ambipolar transport characteristics with both electron and hole mobility above 0.1 cm(2) V-1 s(-1) as elaborated with organic thin-film transistors (OTFTs). The polymer TIG-4FTVT delivers the best device performance. With this polymer, n-channel OTFTs with electron mobility up to 1.67 cm(2) V-1 s(-1) and p-channel OTFTs with hole mobility up to 0.62 cm(2) V-1 s(-1) are fabricated by modifying source/drain electrodes with polyethylenimine ethoxylated (PEIE) and MoO3, respectively, to selectively inject electrons and holes.

关键词： ambipolar polymer semiconductors conjugated polymers direct arylation polycondensation organic thin-film transistors thienoisoindigo

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Blended Tea Ameliorates T2DM via Modulation of Gut Microflora

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PLANT FOODS FOR HUMAN NUTRITION 2024年第4期79卷 851-859页

作者： Liu, Sui Dai, Xinyue Zhao, Jinqi zhang, xuwen Zhu, Mingzhi Wang, Kunbo Fu, Donghe Hunan Agr Univ Key Lab Tea Sci Minist Educ Changsha 410128 Hunan Peoples R China Hunan Agr Univ Natl Res Ctr Engn Technol Utilizat Funct Ingredien Changsha 410128 Hunan Peoples R China Hunan Agr Univ Coinnovat Ctr Educ Minist Utilizat Bot Funct Ingredients Changsha 410128 Hunan Peoples R China Hunan Agr Univ Key Lab Evaluat & Utilizat Gene Resources Hort Cro Minist Agr & Rural Affairs China Changsha 410128 Hunan Peoples R China

Increasing evidences suggest that type 2 diabetes mellitus (T2DM) is closely related to gut microflora dysbiosis, which can be improved by dietary intervention. Four natural plant products, including Cyclocarya paliurus, Fu brick tea, Ampelopsis grossedentata, and Lithocarpus litseifolius, were blended to form a blended tea product for obtaining the better flavor. The blended tea was also expected to have excellent pharmacological activity. Therefore, the ameliorative effect of blended tea on T2DM and underlying mechanisms were studied in this study. The results showed that the blended tea extract effectively attenuated the symptoms of glucose and lipid metabolism-related disorders in T2DM mice fed by high-fat and high-sucrose diet. Furthermore, blended tea extract intervention significantly attenuated gut microbiota dysbiosis, the abundance of bacteria such as Bacteroidetes and Firmicutes, which aid in the hydrolysis and utilization of carbohydrates, significantly increased, while the abundance of pathogenic bacteria such as Proteobacteria significantly decreased. Certain core microorganisms involved in energy metabolism, including Ruminococcaceae_UCG-005, Butyricimonas, Roseburia, Oscillibacter, [Eubacterium]_nodatum_group, Muribaculaceae, Prevotellaceae UCG 001, were also found to be improved by blended tea extract. Collectively, our results demonstrated that the blended tea may ameliorate T2DM through modulation of gut microflora. The blended tea may serve as novel functional drink for the treatment of T2DM and dysbiosis of gut microbiota.

关键词： Blended tea(1) T2DM(2) Gut microflora(3) Gut Microflora dysbiosis(4)

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Employing supercritical n-butanol to remove the EVA film for the delamination of photovoltaic laminated module

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JOURNAL OF SUPERCRITICAL FLUIDS 2025年 219卷

作者： Wang, xuwen Liu, Zhifeng Ruan, Haoda Li, Xinyu zhang, Lei Hefei Univ Technol Sch Mech Engn Hefei 230009 Peoples R China Anhui Prov Key Lab Low Carbon Recycling Technol & Hefei 230009 Peoples R China State Key Lab Environm Adaptabil lndustrial Prod Guangzhou 510300 Peoples R China

The rapid advancement of the photovoltaic (PV) industry has elevated the recycling and reuse of decommissioned PV modules to critical challenges, essential for tackling environmental concerns and achieving resource reutilization. To facilitate the efficient layering of PV modules and recovery of valuable materials, this study proposes a PV module degradation and recycling process utilizing supercritical n-butanol. A systematic evaluation was conducted to assess the effects of various factors on the dissolution ratio of PV modules, with an appropriate range of process parameters selected for optimization. A second-order regression model was developed to predict the dissolution ratio of the EVA film. Comparison of actual dissolution ratio with model predictions confirmed the high accuracy of the fitted model. Finally, characterization and elemental analysis of cells recovered from the supercritical process demonstrated the effectiveness of this recycling method, achieving more thorough degradation on the cell surfaces.

关键词： Photovoltaic Supercritical n-butanol Degradation Recycling Characterization

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Direct Arylation Polycondensation of β-Fluorinated Bithiophenes to Polythiophenes: Effect of Side Chains in C-Br Monomers

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MACROMOLECULES 2022年第18期55卷 8095-8105页

作者： zhang, xuwen Shi, Yibo Dang, Yanfeng Liang, Ziqi Wang, Zhongli Deng, Yunfeng Han, Yang Hu, Wenping Geng, Yanhou Tianjin Univ Sch Mat Sci & Engn Tianjin 300072 Peoples R China Tianjin Univ Tianjin Key Lab Mol Optoelect Sci Tianjin 300072 Peoples R China Collaborat Innovat Ctr Chem Sci & Engn Tianjin Sch Mat Sci & Engn Tianjin 300072 Peoples R China Tianjin Univ Dept Chem Tianjin 300072 Peoples R China Collaborat Innovat Ctr Chem Sci & Engn Tianjin Tianjin Key Lab Mol Optoelect Sci Tianjin 300072 Peoples R China Tianjin Univ Natl Univ Singapore Joint Sch Int Campus Fuzhou 350207 Peoples R China Tianjin Univ Int Campus Fuzhou 350207 Peoples R China

Six polythiophenes (PThs) were synthesized via direct arylation polycondensation (DArP) with beta-fluorinated bithiophenes, that is, 4,4' -difluoro-2,2'-bithiophene (2FBT) and 3,3',4,4'-tetrafluoro-2,2'-bithiophene (4FBT), as the C-H monomers and 5,5'-dibromo-2,2'-bithiophenes DCBT-2Br, DABT-2Br, and DTBT-2Br that carry alkoxycarbonyl, alkyl, and alkylthienyl side chains at 4,4'-positions, respectively, as the C-Br monomers. Both 2FBT and 4FBT are highly reactive for DArP, and high molecular weight PThs with unobservable chain defects were successfully synthesized from 2FBT/DCBT-2Br, 2FBT/DABT-2Br, 2FBT/DTBT-2Br, and 4FBT/DTBT-2Br. However, the DArP of 4FBT with DCBT-2Br and DABT-2Br produced PThs containing C-H/C-H homo-coupling defects along with relatively lower molecular weights. Detailed theoretical analysis suggests that the occurrence of C-Br reduction-provoked C-H/C-H homo-coupling for 4FBT/DCBT-2Br and 4FBT/DABT-2Br monomer pairs originated from the poor selectivity between the cis- and trans-forms of transition states in the concerted metalation-deprotonation (CMD) process is responsible for the formation of structural defects and depressed molecular weights. This research reveals that a C-H monomer with high reactivity and selectivity is not sufficient for the synthesis of well-defined conjugated polymers via DArP, and the structure of the C-Br monomer also has a significant impact on the results of DArP via influencing the catalytic cycles.

关键词： Defects Monomers Polymerization Polymers Selectivity

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