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Direct Synthesis of Nitriles from Aldehydes in Ionic Liquids

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Chemical Research in Chinese Universities 2011年第4期27卷 712-714页

作者： ZHANG Jun-li CHEN Xiao-rong yu yan-peng XU Kun-ling HUANG Jun State Key Laboratory of Materials-Oriented Chemical Engineering College of Chemistry and Chemical Engineering Nanjing University of Technology Nanjing 210009 P. R. China

1 Introduction Ionic liquids（ILs） are environmentally acceptable solvents because they have low vapor pressure, high thermal stability and chemical stability, excellent solvent for organic and inorganic compounds. Therefore, they can be used as green solvents for a number of chemical processes, such as separa- tions and reactions. ILs are also used as catalysts in chemical reactions to accelerate reaction rate and improve selectivity.

关键词： Nitrile Aldehyde Hydroxylamine hydrochloride Ionic liquid

Research on Bast Fiber Extracted from the White Bark of Three Species in the Genus Broussonetia

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Chinese Journal of Polymer Science 2024年第6期42卷 729-738页

作者： Shan-Shan Jin Si-Nong Wang yan-yan Huang Jing-yu Zhang peng Liu Hui yu Hong-Dong Zhang yu-Liang yang Institute for Preservation and Conservation of Chinese Ancient Books Fudan University LibraryFudan UniversityShanghai200433China State key laboratory of Molecular Engineering of polymers Department of Macromolecular ScienceFudan UniversityShanghai200433China

Against the backdrop of a global paper resource shortage,there is a growing need to identify fast-growing tree species capable of producing long-lasting *** plant species namely Broussonetia kazinoki,Broussonetia papyrifera and hybrid paper mulberry,belong to the Broussonetia genus,were collected from China to study their white bark suitability for pulp and *** chemical composition revealed that the holocellulose content in Broussonetia kazinoki and Broussonetia papyrifera was more than 80%.The molecular weight distribution of several holocellulose/α-cellulose is observed by GPC,which allows us to better observe the changes of various components on the molecular *** yield,lignin,whiteness,and molecular weight of the pulps obtained by NaOH treatment were *** microscope was used to characterize the fiber length-width ratio and ***,the improvement of the fiber rigidity method based on the Kratky-Porod chain model makes it more theoretical and further reveals the influencing factors of fiber *** study demonstrates the high potentiality of these three species for papermaking applications.

关键词： Broussonetia genus Cellulose Alkaline pulping Kratky-Porod chain model Fiber rigidity

Thermal and mechanical behavior of casting copper alloy wheel during wheel and belt continuous casting process

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China Foundry 2024年第1期21卷 82-90页

作者： Kun Gao yan peng School of Mechanical Engineering Yanshan UniversityQinhuangdao 066004HebeiChina

To investigate the thermal and mechanical behavior of casting wheel,a two-dimensional thermoelastic-plastic finite element model was used to predict the temperature,stress and distortion distribution of the casting wheel during the wheel and belt continuous casting *** effects of grinding thickness and casting speed on the thermal and mechanical behaviors of the center of the hot face of the casting wheel were discussed in *** each rotation,the casting wheel passes through four different spray *** results show that the temperature distribution of the casting wheel in different spray zones is similar,the temperature of the hot face is the highest and the temperature reaches the peak in the spray zoneⅢ.The stress and distortion depend on the temperature distribution,and the maximum stress and distortion of the hot face are 358.2 MPa and 1.82 mm,*** temperature at the center of the hot face decreases with increasing grinding thickness and increases with increasing casting speed.

关键词： casting wheel finite element model grinding thickness casting speed hot face spray zones

Numerical simulation of fluid flow and free surface fluctuations during wheel and belt casting process

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Journal of Iron and Steel Research International 2024年第5期31卷 1117-1126页

作者： Kun Gao yan peng National Engineering Research Center for Equipment and Technology of Cold Strip Rolling Yanshan UniversityQinhuangdao066004HebeiChina

The unstable fluid flow and severe free surface fluctuations in the wheel and belt caster can affect the quality of the cast *** lower level height tends to entrap inclusions in the molten *** the other hand,the higher level height makes the production process more dangerous due to the overflow of high temperature fluid from the mold.A computational model of the molten metal pouring process was *** transient fluid flow and free surface fluctuations behavior were calculated using the three-dimensional large eddy simulation model and the volume of fluid *** results show that the flow velocity of the main jet gradually decreases under the influence of the low kinetic energy fluid in the *** is an obvious oscillation in the tail of the jet,while the flow field is asymmetric in *** jet is closer to the inside radius side due to the Coanda effect,and there is a recirculation zone on the inside radius and the outside radius respectively,according to the 10 s time-averaged *** with the industrial observation and simulation results,the shape of the free surface is a wave that varies with *** addition,the free surface height is lowest and the flow velocity is highest in the region near the jet.

关键词： Fluid flow Free surface Wheel and belt caster Large eddy simulation Volume of fluid method

Experimental and numerical study on atmospheric-pressure air dielectric barrier discharge via 50 Hz/5000 Hz dual-frequency excitation

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High Voltage 2024年第2期9卷 391-402页

作者： Junwen He Bangfa peng Guanglin yu Ronggang Wang Nan Jiang Jie Li yan Wu School of Electrical Engineering Dalian University of TechnologyDalianChina Canmax Technologies Co. Ltd.SuzhouChina

A dual-frequency(DF)dielectric barrier discharge,excited by the superposition of a 50 Hz low frequency(LF)and a 5000 Hz intermediate frequency(IF),is proposed to enhance *** effect of the LF voltage component on the breakdown behaviour of the DF discharge during different periods has been studied both experimentally and *** number of high-current pulses rises as the LF voltage *** statistical analysis shows that the number of the current pulse amplitude above 80 mA in the DF discharge reaches nearly 6 times that in the IF ***,the total discharge energy in the DF discharge is significantly higher than that in the IF *** simulation re-produces the temporal variation of the breakdown behaviours in the DF *** simulated results reveal that the maximal electric field strength of the breakdown process is greater in the DF discharge compared to the IF discharge during a half-period of ***,the comparison between the IF and DF discharges exhibits that the LF voltage regulates the accumulation of residual charged species on the dielectric surface after the breakdown by modulating the residual voltage between the air gap.

关键词： dielectric excitation excited

Intestinal microecological transplantation for a patient with chronic radiation enteritis:A case report

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World Journal of Gastroenterology 2024年第19期30卷 2603-2611页

作者： Lin Wang yan Li yu-Jing Zhang Li-Hua peng Department of Gastroenterology and Hepatology The First Medical CenterChinese PLA General HospitalBeijing 100853China Department of Gastroenterology and Hepatology Chinese PLA Medical SchoolBeijing 100853China

BACKGROUND The gut microbiota is strongly associated with radiation-induced gut *** study aimed to assess the effectiveness and safety of intestinal microecological transplantation for treating patients with chronic radiation *** SUMMARY A 64-year-old female with cervical cancer developed abdominal pain,diarrhea,and blood in the stool 1 year after *** electronic colonoscopy was performed to diagnose chronic radiation *** courses of intestinal microecological transplantation and full-length 16S rRNA microbiological analysis were *** patient experienced short-and long-term relief from symptoms without adverse *** 16S rRNA sequencing revealed significant differences in the intestinal flora’s composition between patient and healthy *** bacteria,such as Escherichia fergusonii and Romboutsia timonensis,were more in the *** bacteria such as Faecalibacterium prausnitzii,Fusicatenibacter saccharivorans,Ruminococcus bromii,and Bifidobacterium longum were more in the healthy *** microbiota transplantation resulted in a significant change in the patient's intestinal flora *** composition converged with the donor's flora,with an increase in core beneficial intestinal bacteria,such as Eubacterium rectale,and a decrease in pathogenic *** in the intestinal flora corresponded with the patients'alleviating clinical *** Intestinal microecological transplantation is an effective treatment for relieving the clinical symptoms of chronic radiation enteritis by altering the composition of the intestinal *** study provides a new approach for treating patients with chronic radiation enteritis.

关键词： Chronic radiation enteritis Gut microbial transplantation Intestinal microecology Cancer Quality of life Case report

A Weighted Flow related to a Trudinger–Moser Functional on Closed Riemann Surface

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Acta Mathematica Sinica,English Series 2024年第9期40卷 2244-2262页

作者： peng Xiu yu School of Mathematics Renmin University of ChinaBeijing 100872P.R.China

In this paper,with(Σ,g)being a closed Riemann surface,we analyze the possible concentration behavior of a heat flow related to the Trudinger–Moser *** obtain a long time existence for the *** along some sequence of times t_(k)→+∞,we can deduce the convergence of the flow in H2(Σ).Furthermore,the limit function is a critical point of the Trudinger–Moser functional under certain constraint.

关键词： Trudinger-Moser inequality global convergence heat flow

Enhancing Tea Leaf Disease Identification with Lightweight MobileNetV2

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Computers, Materials & Continua 2024年第7期80卷 679-694页

作者： Zhilin Li yuxin Li Chunyu yan peng yan Xiutong Li Mei yu Tingchi Wen Benliang Xie College of Big Data and Information Engineering Guizhou UniversityGuiyang550025China Power Semiconductor Device Reliability Engineering Center of the Ministry of Education Guiyang550025China State Key Laboratory of Public Big Data Guizhou UniversityGuiyang550025China The Mushroom Research Centre Guizhou UniversityGuiyang550025China The Engineering Research Center of Southwest Bio-Pharmaceutical Resources Ministry of EducationGuizhou UniversityGuiyang550025China

Diseases in tea trees can result in significant losses in both the quality and quantity of tea *** monitoring can help to prevent the occurrence of large-scale diseases in tea ***,existingmethods face challenges such as a high number of parameters and low recognition accuracy,which hinders their application in tea plantation monitoring *** paper presents a lightweight I-MobileNetV2 model for identifying diseases in tea leaves,to address these *** proposed method first embeds a Coordinate Attention(CA)module into the originalMobileNetV2 network,enabling the model to locate disease regions ***,a Multi-branch Parallel Convolution(MPC)module is employed to extract disease features across multiple scales,improving themodel’s adaptability to different disease ***,the AutoML for Model Compression(AMC)is used to compress themodel and reduce computational *** results indicate that our proposed algorithm attains an average accuracy of 96.12%on our self-built tea leaf disease dataset,surpassing the original MobileNetV2 by 1.91%.Furthermore,the number of model parameters have been reduced by 40%,making itmore suitable for practical application in tea plantation environments.

关键词： Disease identification coordinate attention mechanism multi-scale feature extraction model pruning

Simple preparation of C(CS)/g-C_(3)N_(4)/Co carbon aerogel and its catalytic performance for ammonium perchlorate

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Defence Technology（防务技术） 2024年第3期33卷 186-196页

作者： yujie yan Bo Jin Rufang peng State Key Laboratory of Environment-friendly Energy Materials School of Materials Science and EngineeringSouthwest University of Science and TechnologyMianyang621010China

Biomass chitosan(CS)was used as a template,graphitic phase carbon nitride(g-C_(3)N_(4))with high nitrogen content and certain catalytic activity was used as a dopant,and nano-transition metal cobalt(Co)was used as a catalytic center *** carbon aerogel(C(CS)/g-C_(3)N_(4)/Co)with a three-dimensional network-like structure was prepared by assembling the three materials through experimental operations such as freeze-drying and high-temperature *** was demonstrated by scanning and transmission characterization that the CS in the carbon aerogel could provide more active sites for the cobalt nanoparticles,and the doping of graphite-phase carbon nitride as a template dispersed the cobalt nanoparticles and changed the conductivity of the *** investigate the catalytic effect of carbon aerogel on ammonium perchlorate(AP),it was investigated by differential thermal analyzer and TG thermal *** carbon aerogel was very effective in catalyzing AP,and the 10 wt% content of the catalyst reduced the AP pyrolysis peak from 703.9 to 595.5 *** to further investigate the synergistic effect of the three materials,further carbon aerogels such as C(CS)/Co,g-C_(3)N_(4)/Co were prepared and applied to catalyze AP,and the same ratio reduced the AP pyrolysis peak by 98.1℃ and 97.7℃.This result indicates a synergistic effect of the assembly of the three materials.

关键词： g-C_(3)N_(4) Chitosan Co Ammonium perchlorate Pyrolysis kinetics