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Green Synthesis of Iron(Ⅱ,Ⅲ)-polyphenol Nanoparticles and Their Adsorption of Malachite Green

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Journal of Wuhan University of Technology(Materials Science) 2024年第4期39卷 1025-1030页

作者：胡玉 zhou Fan ZHANG Nan PAN Xiaobin LI Shiying ZHANG dong LI Li 张玲帆 Department of Chemistry and Environmental Engineering Hanjiang Normal UniversityShiyan 442000China Shiyan Hydrological and Water Resources Survey Bureau of Hubei Province Shiyan 442000China School of Chemistry and Molecular Engineering East China University of Science and TechnologyShanghai 200237China

Three kinds of iron nanoparticles(FeNPs)were prepared via green route based on pomegranate(PG),green tea(GT),and mulberry(ML)extracts under ambient *** obtained materials were characterized by scanning electron microscopy(SEM),transmission electronic microscopy(TEM),X-ray energy-dispersive spectrometer(EDS),X-ray diffraction(XRD),fourier transform infrared spectroscopy(FTIR),and X-ray photoelectron spectroscopy(XPS)*** experimental results show that FeNPs were in the form of amorphous iron(Ⅱ,Ⅲ)-polyphenol complex with different dispersity and ***-Fe has the smallest size range of 25-35 nm,PG-Fe has a moderate size-distribution of 30-40 nm,while ML-Fe formed a tuberous net-type with a sheeting ***-Fe displays the highest removal efficiency of 90.2%in 20 min towards cationic dye of malachite green(16.6%by ML-Fe and 69.3%by GT-Fe),which is attributed to its highest polyphenol content,lowest zeta potential,as well as the most Fe^(2+)on the surface of *** removal mechanism was mainly induced by electrostatic adsorption based on pH and zeta potential tests.

关键词： iron nanoparticles pomegranate green tea mulberry adsorption

Atomic-Scale Insights into Damage Mechanisms of GGr15 Bearing Steel Under Cyclic Shear Fatigue

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Acta Metallurgica Sinica(English Letters) 2024年第7期37卷 1265-1278页

作者： Qiao-Sheng Xia dong-Peng Hua Qing zhou Ye-Ran Shi Xiang-Tao Deng Kai-Ju Lu Hai-Feng Wang Xiu-Bing Liang Zhao-dong Wang State Key Laboratory of Solidification Processing Center of Advanced Lubrication and Seal MaterialsNorthwestern Polytechnical UniversityXi’an710072China State Key Laboratory of Rolling and Automation Northeastern UniversityShenyang110819China Defense Innovation Institute Academy of Military ScienceBeijing100071China

Alternating shear stress is a critical factor in the accumulation of damage during rolling contact fatigue,severely limiting the service life of ***,the specific mechanisms responsible for the cyclic shear fatigue damage in bearing steel have not been fully *** the mechanical response and microstructural evolution of a model GGr15 bearing steel under cyclic shear loading are investigated through the implementation of molecular dynamics *** samples undergo 30 cycles under three different loading conditions with strains of 6.2%,9.2%,and 12.2%,*** findings indicate that severe cyclic shear deformation results in early cyclic softening and significant accumulation of plastic damage in the bearing ***,samples subjected to higher strain-controlled loading exhibit higher plastic strain energy and shorter fatigue ***,strain localization is identified as the predominant damage mechanism in cyclic shear fatigue of the bearing steel,which accumulates and ultimately results in fatigue ***,simulation results also revealed the microstructural reasons for the strain localization(e.g.,BCC phase transformation into FCC and HCP phase),which well explained the formation of white etching *** study provides fresh atomic-scale insights into the mechanisms of cyclic shear fatigue damage in bearing steels.

关键词： Cyclic shear fatigue Molecular dynamic simulation Bearing steels Plastic damage accumulation

Influence of Chain Architectures on Crystallization Behaviors of PLLA Block in PEG/PLLA Block Copolymers

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Chinese Journal of Polymer Science 2019年第3期37卷 258-267页

作者： Sheng Xiang dong-dong zhou Li-dong Feng Xin-Chao Bian Gao Li Xue-Si Chen Tian-Chang Wang Key Laboratory of Polymer Ecomaterials Changchun Institute of Applied Chemistry Chinese Academy of Sciences Jilin Biomedical Polymers Engineering Laboratory University of Chinese Academy of Sciences South China Advanced Institute for Soft Matter Science and Technology South China University of Technology

The effect of the architecture of poly(ethylene glycol)/poly(L-lactide)(PEG/PLLA) block copolymers on the non-isothermal crystallization behaviors of PLLA blocks was investigated by differential scanning calorimetry(DSC) and wide angle X-ray diffraction(WAXD). 1-Arm MPEG-b-PLLA and 4-arm PEG-b-PLLA(4PEG-b-PLLA) were synthesized by the ring-opening polymerization of Llactide in the presence of poly(ethylene glycol) methyl ether(MPEG) and 4-arm poly(ethylene glycol)(4PEG). 4-Arm PLLA-b-MPEG(4PLLA-b-PEG) was synthesized by coupling 4-arm PLLA and MPEG. The WAXD results indicated that the crystalline structure of PLLA blocks did not alter due to the different chain architectures. The average values of Avrami index(ˉn) were all above 4, which indicated that the nucleation mechanism of PLLA blocks was heterogeneous nucleation, regardless of the architectures. The overall crystallization rates were decreased markedly as following: MPEG-b-PLLA > 4PEG-b-PLLA > 4PLLA-b-PEG, ascribed to the different confinement by PEG blocks and to the steric hindrance of chain architectures. Therefore, the crystallization of PLLA blocks became more difficult and the crystallization activation energy of the PLLA blocks increased due to the confinement of chain architectures.

关键词： Poly(L-lactide) Poly(ethylene glycol)/poly(L-lactide)block copolymer Non-isothermal crystallization Chain architecture

Experimental Study on Mixed-Mode(Ⅰ–Ⅱ)Fracture Toughness of Freshwater Ice

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Acta Mechanica Solida Sinica 2024年第2期37卷 252-264页

作者： Yaozhong Xu Mao zhou Xian Yi Wen Hua Jiuzhou Huang Wenyu Zhang Shiming dong Key Laboratory of Deep Underground Science and Engineering Ministry of EducationCollege of Architecture and EnvironmentSichuan UniversityChengdu610065China Failure Mechanics and Engineering Disaster Prevention Key Laboratory of Sichuan Province Sichuan UniversityChengdu610065China China Aerodynamics Research and Development Center/Low Speed Aerodynamics Research Institute Mianyang621000China College of Mechanical and Electrical Engineering Xichang UniversityXichang615000China

In recent years,the issue of aircraft icing has gained widespread *** breaking and detachment of dynamic ice can pose a threat to flight ***,the shedding and fracture mechanisms of dynamic ice are unclear and cannot meet the engineering needs of ice-shedding hazard ***,studying the fracture toughness of ice bodies has extremely important practical *** address this issue,this article uses a centrally cracked Brazilian disk(CCBD)specimen to measure the pure modeⅠtoughness and pure modeⅡfracture toughness of freshwater ice at different loading *** mixed-mode(Ⅰ–Ⅱ)fracture characteristics of ice are discussed,and the experimental results are compared and analyzed with the theoretical values of the generalized maximum tangential stress(GMTS)criterion considering the influence of *** results indicated that as the loading rate increases,the pure modeⅠtoughness and pure modeⅡfracture toughness of freshwater ice decrease,and the fracture toughness of freshwater ice is more sensitive to the loading rate.Ⅰn terms of fracture criteria,the theoretical value of the ratio of pure modeⅡfracture toughness to pure modeⅠfracture toughness based on the GMTS criterion is in good agreement with the experimental value,while the theoretical value based on the maximum tangential stress(MTS)criterion deviates significantly from the experimental value,indicating that the GMTS criterion considering the influence of T-stress can better predict the experimental results.

关键词： Freshwater ice Fracture criteria Centrally cracked Brazilian disk(CCBD) Mixed-mode(Ⅰ-Ⅱ) Loading rate

TSC prediction and dynamic control of BOF steelmaking with state-of-the-art machine learning and deep learning methods

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Journal of Iron and Steel Research(International) 2024年第1期31卷 174-194页

作者： Tian-yi Xie Cai-dong Zhang Quan-lin zhou Zhi-qiang Tian Shuai Liu Han-jie Guo Material Technology Research Institute Hesteel GroupShijiazhuang050023HebeiChina Tangsteel Company Hesteel GroupTangshan063611HebeiChina School of Artificial Intelligence Beijing Technology and Business UniversityBeijing100048China School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing100083China

Mathematical(data-driven)models based on state-of-the-art(SOTA)machine learning and deep learning models and data collected from 12,786 heats were established to predict the values of temperature,sample,and carbon(TSC)test,including temperature of molten steel(TSC-Temp),carbon content(TSC-C)and phosphorus content(TSC-P),which made prepa-ration for eliminating the TSC *** maximize the prediction accuracy of the proposed approach,various models with different inputs were implemented and compared,and the best models were applied to the production process of a Hesteel Group steelmaking plant in China in the *** number of tabular features(hot metal information,scrap,additives,blowing practices,and preset values)was expanded,and time series(off-gas profiles and blowing practice curves)that could reflect the entire steelmaking process were introduced as ***,the latest machine learning models(LightGBM,CatBoost,TabNet,and NODE)were used to make predictions with tabular features,and the best coefficient of determination R^(2)values obtained for TSC-P,TSC-C and TSC-Temp predictions were 0.435(LightGBM),0.857(Cat-Boost)and 0.678(LightGBM),respectively,which were higher than those of classic models(backpropagation and support vector machine).Then,making predictions was performed by using SOTA time series regression models(SCINet,DLinear,Informer,and MLSTM-FCN)with original time series,SOTA image regression models(NesT,CaiT,ResNeXt,and GoogLeNet)with resized time series,and the proposed Concatenate-Model and Parallel-Model with both tabular features and time *** optimization and comparisons,it was finally determined that the Concatenate-Model with MLSTM-FCN,SCINet and Informer as feature extractors performed the best,and its R^(2)values for predicting TSC-P,TSC-C and TSC-Temp reached 0.470,0.858 and 0.710,*** field test accuracies for TSC-P,TSC-C and TSC-Temp were 0.459,0.850 and 0.685,respectively.A related importance analysis was carri

关键词： BOF steelmaking In-blow prediction TSC test Machine learning Deep learning Field application

Research on the novel asymmetric frequency division duplex technique

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The Journal of China Universities of Posts and Telecommunications 2006年第4期13卷 13-18页

作者： ZHANG Ying-hai WANG Wei-dong dong Yu zhou Kai-Jie Information and Electronics Technology Laboratory Beijing University of Posts and Telecommunications Beijing 100876 China

This article introduces a novel duplex transmission technique-asymmetric frequency division duplex （AFDD）. One of the characteristics in future mobile systems is asymmetric characteristic caused by service requirement and electromagnetic radiation, AFDD is designed to adapt to the new asymmetric characteristics. The AFDD puts forward a novel adaptive frequency-allocation scheme in downlink and uplink. Combining AFDD with code division multiple access （CDMA） communication system, it is proven that AFDD improves the capacity and coverage of the system compare with FDD CDMA system.

关键词： asymmetric characteristics AFDD Duplex Mobile communications

Experimental study on wax deposition of highly paraffinic oil in intermittent gas-oil flow in pipelines

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Petroleum Science 2024年第3期21卷 2080-2088页

作者： Chuan-Shuo Wang Qian-Li Ma Xiao-Fang Lv Jie Zhang Yang Liu Shi-dong zhou Jiangsu Key Laboratory of Oil and Gas Storage and Transportation Technology Changzhou University Hade Oil and Gas Development Department Tarim Oilfield Branch

Oil-gas two phase wax deposition is a fairly common and open-ended question in flow assurance of multiphase transportation pipelines. This paper investigated the two main aspects of oil-gas two phase wax deposition layer: apparent thickness and crystal structure characteristics. A typical highly paraffinic oil in Bohai Sea, China, was used as the experimental material to investigate the wax deposition thickness in oil-gas two phase under the influence of different oil temperatures, superficial gas/liquid phase velocities and gas-oil ratios by using multiphase flow loop experimental device. Just as in the classical theory of wax molecular diffusion, it showed that wax deposition thickness of oil-gas two phase increased with increasing oil temperature. Analysis of the impact of different superficial phase velocities found that the actual liquid flow heat transfer and shear stripping was the gas phase dominant mechanisms determining wax deposit thickness. In addition, the crystal structure of the wax deposition layer was characterized with the help of small-angle X-ray scattering(SAXS) for different circumferential positions, flow rates and gas-oil ratios. The bottom deposition layer had a complex crystal structure and high hardness, which were subject to change over flow rate variations. Furthermore, the SAXS results provided evidence that the indirect effect of the actual liquid velocity modified by the gas phase was the main mechanism. Our study of the effect of gas phase on the wax deposition of oil-gas two phase will help shed light onto the mechanism by which this important process occurs. Our findings address a very urgent need in the field of wax deposition of highly paraffinic oil to understand the flow security of oilgas two phase that occurs easily in multiphase field pipelines.

关键词： Oil-gas two phase Highly paraffinic oil Wax deposition SAXS

Developing a fluorescence substrate for HRP-based diagnostic assays with superiorities over the commercial ADHP

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Chinese Chemical Letters 2024年第6期35卷 439-444页

作者： Zhichao zhou Fuqian Chen Xiaotong Xia dong Ye Rong zhou Lei Li Tao Deng Zhenhua Ding Fang Liu Department of Radiation Medicine Guangdong Provincial Key Laboratory of Tropical Disease ResearchSchool of Public HealthSouthern Medical UniversityGuangzhou 510515China School of Pharmaceutical Sciences Guangzhou University of Chinese MedicineGuangzhou 510006China Artemisinin Research Center Guangzhou University of Chinese MedicineGuangzhou 510006China State Key Laboratory of Respiratory Disease the First Affiliated Hospital of Guangzhou Medical UniversityGuangzhou Medical UniversityGuangzhou 510120China Guangzhou Laboratory Bio-IslandGuangzhou 510030China Nanshan Pharmaceutical Innovation Research Institute of Guangdong Province Foshan 528225China

The combination of horseradish peroxidase(HRP)and a fluorescence substrate has been attracting great interests in developing sensitive biochemical analysis and immunoassays.10-Acetyl-3,7-dihydroxyphenoxazine(ADHP or Amplex red)is the most sensitive fluorogenic substrate known for HRP in current market,however,it suffers from some drawbacks,such as non-specific reactivity to carboxylesterase and limited fluorescence *** the present study,a novel HRP substrate10-cyclopropylcarbonyl-dichloro-dihydroxyphenoxazine(AR-2),has been prepared,which exhibited improved sensitivity than ADHP in sensing ***,the fluorescence of AR-2/HRP demonstrated improved tolerance to physiological relevant p H fluctuation as compared to ADHP/*** detection of uric acid/urate oxidase reaction indicated excellent application prospect of AR-2/HRP for monitoring H_(2)O_(2)-generating biochemical *** interestingly,an enzyme-linked immunosorbent assay(ELISA)using AR-2 as the fluorescence reporter has been successfully used in detecting IgG against severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)from human serum ***,AR-2 exhibits improved performances over the commercial ADHP,which will be an ideal alternative to ADHP in HRP-based fluorescence biochemical analysis and immunoassays.

关键词： Fluorescence immunoassay HRP fluorescence substrate Hydroresorufin Amplex red/ADHP SARS-CoV-2

Surface engineering of Li-and Mn-rich layered oxides for superior Li-ion battery

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Tungsten 2024年第1期6卷 259-268页

作者： Lu-Xiang Ma Tian-dong Chen Chun-Xi Hai Sheng-De dong Xin He Qi Xu Hang Feng AXin Ji-Tao Chen Yuan zhou College of Materials and Chemistry and Chemical Engineering Chengdu University of TechnologyChendu 610000China Qinghai Building and Materials Research Co. LtdXining 810000China Beijing National Laboratory for Molecular Sciences College of Chemistry and Molecular EngineeringPeking UniversityBeijing 100871China

The Li-and Mn-rich layered oxides(R-LNCM)are considered as promising cathode materials for high-energy density lithium-ion batteries(LIBs).However,the interface side reaction aggravates the voltage and capacity fading between cathode material and electrolyte at high voltage,which severely hinders the practical application of LIB ***,lithium polyacrylate(LiPAA)as the binder and coating agent is applied to suppress the voltage and capacity fading of R-LNCM *** flexible LiPAA layers with high elasticity are capable of impeding cathode cracks on the particle surface via mechanical stress ***,superior voltage and capacity fading suppression on R-LNCM electrode is finally *** a result,LiPAA-R-LNCM cathode exhibits a remarkable specific capacity of 186 mA·h·g^(-1)with~73%retention at 1℃after ***,the corresponding average discharge potential is maintained to~3.1 V with only~0.4 V falling.

关键词： LiPAA interphase layer Interface side reaction Cathode cracks Capacity and voltage fading suppression Liand Mn-rich cathode