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Preparation and Rheological Characterization of Long Chain Branching Polyglyco.ide

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Chinese Journal of Polymer Science 2024年第8期42卷 1177-1184页

作者： Wei-Lin Liu Ming-Fu Lyu Heng-Yuan Zhang Jian-Ye Liu Shi-Jun Zhang Beijing University of chemical Technology Beijing 100029China SINOPEC(Beijing)Research Institute of chemical Industry co. Ltd.Beijing 100013China

The long chain branching(LCB)polyglyco.ide(PGA)was successfully prepared by the successive reactions of the terminal hydroxyl groups of PGA with triglycidyl isocyanurate(TGIC)and pyromellitic dianhydride(PMDA).The influence of LCB produced by functional group reaction on rheological and crystallization behavior was studied and discussed through linear rheology,uniaxial elongation and DSC(differential scanning calorimetry).The much higher visco.ity and the more notable strain hardening behavior of modified PGA indicates the LCB with high degree of entanglements are *** melt strength of PGA is finally improved greatly and can make su re that the supercritical co.(2)foaming can be carried out successfully.

关键词： Polyglyco.ide(PGA) Long chain branching(LCB) Rheology

co.tinuous synthesis of N,N-dicyanoethylaniline in microreactors:Reaction kinetics and process intensification

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Chinese Journal of chemical Engineering 2024年第8期72卷 95-105页

作者： Pengcheng Lu Yaoyao Li Jianjun Zhang Yuchao Zhao Qingqiang Wang Ying Chen Nan Jin Xiugang Yu Shandong Provincial Key Laboratory of chemical Engineering and Process College of Chemistry and Chemical EngineeringYantai UniversityYantai 264005China Shandong ANOKY chemical Technology Research co. Ltd.Yantai 265601China Yantai Guobang chemical Machinery Technology co. Ltd.Yantai 264000China

Cyanoethylation of phenylamine is one of the important steps for the production of dicyanoethyl-based disperse ***,the exothermic nature of this reaction and the inherent instability of intermittent dynamic operation pose challenges in achieving both high safety and reaction *** this study,a co.tinuous cyanoethylation of phenylamine for synthesizing N,N-dicyanoethylaniline in a microreactor system has been *** optimizing the reaction co.ditions,the reaction time was significantly reduced from over 2 h in batch operation to approximately 14 min in the microreactor,while high co.version and selectivity were *** on the reaction network co.structed,the reaction kinetics was established,and the kinetic parameters were then *** findings provide valuable insights into a co.trollable cyanoethylation reaction,which would be helpful for the design of efficient processes and optimization of reactors.

关键词： Cyanoethylation Microreactor Kinetics N,N-dicyanoethylaniline Optimization Safety

Preparation of sodium molybdate from molybdenum co.centrate by microwave roasting and alkali leaching

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International Journal of Minerals,Metallurgy and Materials 2024年第1期31卷 91-105页

作者： Fengjuan Zhang Chenhui Liu Srinivasakannan Chandrasekar Yingwei Li Fuchang Xu School of Chemistry and Environment Yunnan Minzu UniversityKunming 650500China chemical Engineering Department Khalifa UniversityAbu DhabiUAE Yunnan Zhong Tai Technology co. Ltd.Kunming 650500China Yunnan Yongchang Silico. Industry co. Ltd.Baoshan 678000China

The preparation process of sodium molybdate has the disadvantages of high energy co.sumption,low thermal efficiency,and high raw material requirement of molybdenum trioxide,in order to realize the green and efficient development of molybdenum co.centrate resources,this paper proposes a new process for efficient reco.ery of molybdenum from molybdenum co.centrate and preparation of sodium molybdate by microwave-enhanced roasting and alkali *** analysis indicated the feasibility of oxidation roasting of molybdenum *** effects of roasting temperature,holding time,and power-to-mass ratio on the oxidation product and leaching product sodium molybdate (Na_(2)MoO_(4)·2H_(2)O) were *** the optimal process co.ditions:roasting temperature of 700℃,holding time of 110 min,and power-to-mass ratio of 110 W/g,the molybdenum state of existence was co.verted from MoS_(2) to Mo *** process of preparing sodium molybdate by alkali leaching of molybdenum calcine was investigated,the optimal leaching co.ditions include a solution co.centration of 2.5 mol/L,a liquid-to-solid ratio of 2 mL/g,a leaching temperature of 60℃,and leaching solution termination at pH *** optimum co.ditions result in a leaching rate of sodium molybdate of 96.24%.Meanwhile,the co.tent of sodium molybdate reaches 94.08wt%after leaching and removing *** and aluminum impurities can be effectively separated by adjusting the pH of the leaching solution with sodium carbonate *** research avoids the shortco.ings of the traditional process and utilizes the advantages of microwave metallurgy to prepare high-quality sodium molybdate,which provides a new idea for the highvalue utilization of molybdenum co.centrate.

关键词： molybdenum metallurgy microwave oxidation roasting removing impurities sodium hydroxide leaching

Design method of extractant for liquid-liquid extraction based on elements and chemical bonds

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Chinese Journal of chemical Engineering 2024年第4期68卷 193-202页

作者： Yuwen Wei Chunling Zhang Yue Zhang Lili Wang Li Xia Xiaoyan Sun Shuguang Xiang Institute of Process System Engineering College of Chemical EngineeringQingdao University of Science and TechnologyQingdao 266042China Yantai Guobang chemical Machinery Technology co. Ltd.Yantai 264002China

In the petrochemical industry process, the relative volatility between the co.ponents to be separated is close to one or the azeotrope that systems are difficult to separate. Liquid-liquid extraction is a co.mon and effective separation method, and selecting an extraction agent is the key to extraction technology research. In this paper, a design method of extractants based on elements and chemical bonds was proposed. A knowledge-based molecular design method was adopted to pre-select elements and chemical bond groups. The molecules were automatically synthesized acco.ding to specific co.bination rules to avoid the problem of “co.bination explosion” of molecules. The target properties of the extractant were set, and the extractant meeting the requirements was selected by predicting the co.relation physical properties of the generated molecules. Based on the separation performance of the extractant in liquid-liquid extraction and the relative importance of each index, the fuzzy co.prehensive evaluation membership function was established, the analytic hierarchy process determined the mass ratio of each index, and the co.sistency test results were passed. The results of case study based on quantum chemical analysis demonstrated that effective determination of extractants for the analysis of benzene-cyclohexane systems. The results unanimously prove that the method has important theoretical significance and application value.

关键词： Molecular design Element and chemical bonds Molecular simulation Thermodynamics Solvent extraction

Novel Method for Evaluating the Aging of Aviation Turbine Engine Oils via High-Temperature Bearing Deposit Tests

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China Petroleum Processing & Petrochemical Technology 2024年第1期26卷 67-77页

作者： Hao Lichun Yang He Song Haiqing Zhou Yunfan He Jingjian Liang Yuxiang SINOPEC Research Institute of Petroleum Processing co. Ltd.Beijing 100083

Aviation turbine engine oils require excellent thermal-oxidative stability because of their high-temperature ***-temperature bearing deposit testing is a mandatory method for measuring the thermal-oxidative performance of aviation lubricant oils,and the relevant apparatus was improved in the present *** different co.mercial aviation turbine engine oils were tested,one with standard performance(known as the SL oil)and the other with high thermal stability,and their thermal-oxidative stability characteristics were *** 100 h of high-temperature bearing testing,the SL oil was analyzed by using various analytical techniques to investigate its thermal-oxidative process in the bearing test,with its thermal-oxidative degradation mechanism also being *** results indicate that the developed high-temperature bearing apparatus easily meets the test requirements of method 3410.1 in standard *** visco.ity and total acid number(TAN)of the SL oil increased with the bearing test time,and various deposits were produced in the bearing test,with the micro-particles of the carbon deposits being sphere-like,rod-like,and sheet-like in *** antioxidant additives in the oil were co.sumed very rapidly in the first 30 h of the bearing test,with N-phenyl-1-naphthylamine being co.sumed faster than ***,the oil thermal-oxidative process involves very co.plex physical and chemical mechanisms.

关键词： aviation turbine engine oil high-temperature bearing deposit test thermal-oxidative degradation antioxidant additives

Surface-state co.trolled synthesis of hydrophobic and hydrophilic carbon dots

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Nano Research 2024年第5期17卷 4391-4399页

作者： Chan Wang Yuan Fang Mi Zhang Huan Zhuo Qijun Song Han Zhu Key Laboratory of Synthetic and Biological co.loids Ministry of EducationSchool of Chemical and Material EngineeringJiangnan UniversityWuxi 214122China Jiangsu Snow Leopard Household chemical co. Ltd.Wuxi 214400China

It is of great significance to synthesize carbon dots(CDs)with desirable hydrophilicity for the ever-growing application of CDs in different *** this study,the hydrophilic and hydrophobic CDs were facilely prepared by solvothermal treatment of o-dihydroxybenzene and urea in N,N-dimethylformamide(DMF).Optimization experiments revealed that the solvothermal temperature has a great impact on the surface states of the *** hydrophobic CDs with a co.tact angle of 110.7°was obtained at 200℃.The structural and optical characterizations,along with theoretical calculations elucidated that the lipophilic nature of the CDs was resulting from the formation of polymer *** presence of extended co.jugated sp^(2)-domains and amino groups co.tributed to the red emission of the CDs synthesized at low reaction temperatures(160-200℃).With the further increase of solvothermal temperature,the hydrophobic CDs were gradually transformed to the hydrophilic state acco.panying the blue shift of the fluorescence of the *** highly hydrophilic CDs with a co.tact angle of 25.9°were obtained at 240℃ due to the increased formation of hydrophilic functional groups on the surface of *** red emissive CDs exhibited a sensitive co.or and fluorescence response to ethanol co.tent while the fluorescence of the blue emissive CDs remained *** co.bining the two kinds of CDs,a dual-emission sensor was co.structed,which was successfully applied for the evaluation of the alco.olic strength in co.mercial Baijiu co.modities in both fluorometric and co.orimetric modes.

关键词： carbon dots surface chemistry hydrophilicity and hydrophobicity solvothermal temperature alco.olic strength evaluation

Recent advances in visible light-mediated chemical transformations of enaminones

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Chinese chemical Letters 2024年第2期35卷 4-15页

作者： Yu Han Liyun Zhou Chengyu Wang Shangti Feng Rong Ma Jie-Ping Wan co.lege of Chemistry and chemical Engineering Jiangxi Normal UniversityNanchang 330022China School of Chemistry and chemical Engineering Linyi UniversityLinyi 276000China Linyi Sanfeng chemical co. Ltd.Linyi 276000China

Enaminones,which possesses both the nucleophilic enamine as well as electrophilic enone structures,are well known versatile building blocks in organic ***,visible light-mediated reactions have emerged as useful synthetic strategy with enhanced *** the last decade,various photochemical transformations of enaminones have been developed to co.struct cyclic or acyclic *** this review,we describe the recent advances in visible light-mediated chemical transformations of *** discussion on the reaction mechanism of the related reactions is given to provide guide to the ***,a summary on the existing challenges and the future outlook towards the development of practical photocatalytic reactions of enaminones is also presented.

关键词： Enaminone Visible light C-H functionalization C=C bond cleavage Cyclization Multico.ponent reactions

Green synthesis of ZSM-5 using silica fume and catalytic co.cracking of lignin and plastics for production of monocyclic aromatics

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Chinese Journal of chemical Engineering 2024年第1期65卷 92-105页

作者： Hongbing Fu Yufei Gu Tianhua Gao Fuwei Li Hengshuo Gu Hucheng Ge Yuke Liu Zhixia Li Hongfei Lin Jiangfei Cao School of Chemistry and chemical Engineering Guangxi UniversityNanning 530004China Guangxi Bossco.Environmental Protection Technology co. Ltd.Nanning 530007China School of Environmental and chemical Engineering Zhaoqing UniversityZhaoqing 526000China

ZSM-5 with hierarchical pore structure was synthesized by a simple two-step hydrothermal crystallization from silica fume without using any organic ammonium *** synthesized ZSM-5 were oval shaped particles with a particle size about 2.0 μm and weak acid-dominated with proper Brønsted(B)and Lewis(L)acid *** ZSM-5 was used for catalytic co.cracking of n-octane and guaiaco.,lowdensity polyethylene(LDPE)and alkali lignin(AL)to enhance the production of benzene,toluene,ethylbenzene and xylene(BTEX).The most significant synergistic effect occurred at n-octane/guaiaco. at 1:1 and LDPE/AL at 1:3,under the co.dition,the achieved BTEX selectivity were 24%and 33%(mass)higher than the calculated values(weighted average).The highest BTEX selectivity reached 88.5%,which was 3.7%and 54.2%higher than those from individual cracking LDPE and *** synthesized ZSM-5 exhibited superior catalytic performance co.pared to the co.mercial ZSM-5,indicating potential application prospect.

关键词： Silica fume ZSM-5 Catalytic co.cracking Plastics Lignin

Experimental and DFT Investigations of AlNbTiVZr High Entropy Alloys with Excellent Mechanical Properties

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Acta Metallurgica Sinica(English Letters) 2024年第9期37卷 1480-1490页

作者： Hongwei Yan Yong'an Zhang Wei Xiao Boyu Xue Rui Liu Xiwu Li Zhihui Li Baiqing Xiong State Key Laboratory of Nonferrous Metals and Processes China GRINM Group Co.Ltd.Beijing100088China GRIMAT Engineering Institute co. Ltd.Beijing101407China General Research Institute for Nonferrous Metals Beijing100088China

This study investigated the microstructure and mechanical properties of AlNbTiVZr series high-entropy alloys(HEAs)through both experimental studies and density functional theory *** improvements in the microstructures and mechanical properties were achieved for the AlNbTiVZr series HEAs by meticulously adjusting the alloy co.position and employing homogenization heat ***,the specimen designated as Al_(0.5)NbTiVZr_(0.5) demonstrated excellent mechanical properties including a co.pressive yield strength of 1162 MPa and a co.pressive strength of 1783 *** homogenization heat treatment at 1000℃ for 24 h,the Al_(0.5)NbTiVZr_(0.5) alloy exhibits brittle-to-ductile *** atomic-scale theoretical simulations reveal that the decrease of Al co.tent intrinsically enhances the ductility of the alloys,thereby indicating that the mechanical properties of the AlNbTiVZr series HEAs were significantly influenced by the chemical ***,specific atomic pair formations were observed to adversely affect the microstructure of the AlNbTiVZr series HEAs,particularly in terms of *** findings provide valuable insights for the design and optimization of light weight HEAs,emphasizing the synergistic adjustment of alloy co.position and heat treatment processes to achieve a balance between the strength and ductility.

关键词： High-entropy alloy Microstructure Mechanical properties Density functional theory