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International Journal of Minerals,Metallurgy and Materials 2011年第6期18卷 683-685页

作者： Fang Xu Yang bai Kai Jiang Li-jie Qiao College of Chemistry and Environmental Science Henan Normal University Xinxiang 453007 China Corrosion and Protection Center Key Laboratory of Environmental Fracture （Ministry of Education） University of Science and Technology Beijing Beijing 100083 China

The electromagnetic properties of Ba2Co1.8Cu0.2Fe12O22 （Co2Y） and Ba3Co2Fe23.4Zn0.6O41 （Co2Z） were studied by measuring microwave scattering *** the transmission spectra of Ba2Co1.8Cu0.2Fe12O22,a forbidden band emerges due to ferromagnetic resonance,and the permeability will turn to negative in the vicinity of the ferromagnetic resonance *** the complex permittivity spectra of Ba3Co2Fe23.4Zn0.6O41,the negative permittivity can be obtained due to dielectric ***,Co2Y and Co2Z can be used to construct left-handed materials possessing negative permeability and negative permittivity simultaneously.

关键词： left-handed materials hexagonal ferrite ferromagnetic materials permeability permittivity resonance

Synthesis of hierarchical porous carbon with high surface area by chemical activation of(NH_(4))_(2)C_(2)O_(4) modified hydrochar for chlorobenzene adsorption

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Journal of Environmental Sciences 2023年第4期126卷 123-137页

作者： jie wen Zewei Liu Hongxia Xi Bichun Huang School of Environment and Energy South China University of TechnologyGuangzhou Higher Education Mega CentreGuangzhou 510006China School of Chemistry and Chemical Engineering South China University of TechnologyGuangzhou 510640China The Key Lab of Pollution Control and Ecosystem Restoration in Industry Clusters Ministry of EducationSouth China University of TechnologyGuangzhou Higher Education Mega CentreGuangzhou 510006China

In this work,hydrothermal technique combined with KOH activation were employed to develop a series of porous carbons (NPCK-x) using tobacco stem as a low-cost carbon source and (NH_(4))_(2)C_(2)O_(4)as a novel nitrogen-doping *** properties of NPCK-x were characterized by Brunauer-Emmett-Teller,field emission scanning electron microscopy,X-ray diffraction,Raman microscope,elemental analysis,and X-ray photoelectron *** showed that the NPCK-x samples possessed large surface areas (maximum:2875 m^(2)/g),hierarchical porous structures,and high degree of disorder.N-containing functional groups decomposed during activation process,which could be the dominant reason for appearance of abundant mesopores and well-developed pore *** chlorobenzene adsorption experiments demonstrated that carbon materials with(NH_(4))_(2)C_(2)O_(4)modification exhibited higher adsorption capacity (maximum:1053 mg/g) than those without modification (maximum:723 mg/g).The reusability studies of chlorobenzene indicated that the desorption efficiency of (NH_(4))_(2)C_(2)O_(4)modified porous carbon reached90.40%after thermal desorption at 100℃ under *** model fitting results exhibited that the existence of mesopores accelerated the diffusion rate of chlorobenzene in porous ***,Grand Canonical Monte Carlo simulation was conducted to verify that micropores with pore sizes of 1.2–2 nm of the optimized porous carbon were the best adsorption sites for chlorobenzene and mesopores with pore sizes of 2–5 nm were also highly active sites for chlorobenzene adsorption.

关键词： Tobacco stem Hierarchical porous carbon N-containing groups Dynamic adsorption Chlorobenzene

Modified ADM1 for modeling free ammonia inhibition in anaerobic acidogenic fermentation with high-solid sludge

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Journal of Environmental Sciences 2017年第2期29卷 58-65页

作者： jie bai He Liu Bo Yin Huijun Ma Xinchun Chen School of Environmental and Civil Engineering Jiangnan UniversityWuxi 214122China

Anaerobic acidogenic fermentation with high-solid sludge is a promising method for volatile fatty acid（VFA） production to realize resource recovery. In this study, to model inhibition by free ammonia in high-solid sludge fermentation, the anaerobic digestion model No. 1（ADM1） was modified to simulate the VFA generation in batch, semicontinuous and full scale sludge. The ADM1 was operated on the platform AQUASIM *** kinds of inhibition forms, e.g., simple inhibition, Monod and non-inhibition forms,were integrated into the ADM1 and tested with the real experimental data for batch and semi-continuous fermentation, respectively. The improved particle swarm optimization technique was used for kinetic parameter estimation using the software MATLAB 7.0. In the modified ADM1, the Ksof acetate is 0.025, the km,acis 12.51, and the KI_NH3is 0.02,respectively. The results showed that the simple inhibition model could simulate the VFA generation accurately while the Monod model was the better inhibition kinetics form in semi-continuous fermentation at pH 10.0. Finally, the modified ADM1 could successfully describe the VFA generation and ammonia accumulation in a 30 m^3full-scale sludge fermentation reactor, indicating that the developed model can be applicable in high-solid sludge anaerobic fermentation.

关键词： High-solid sludge ADM1 Semi-continuous Full scale Free ammonia inhibition

Characterization of a Y-type hexagonal ferrite-based frequency tunable microwave absorber

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International Journal of Minerals,Metallurgy and Materials 2012年第5期19卷 453-456页

作者： Fang Xu Yang bai Kai Jiang Li-jie Qiao College of Chemistry and Environmental Science Henan Normal University Xinxiang 453007 China Engineering Technology Research Center of Motive Power and Key Materials of Henan Province Xinxiang 453007 China Corrosion and Protection Center The Key Laboratory of the Ministry of Education of China for Environmental Fracture University of Science and Technology BeijingBeijing 100083 China

A Y-type hexaferrite rod with the composition of Ba2COl.8Cuo.2Fe12022 was presented as an absorbing material with high absorb- anee. Its high absorbance and wide absorption band result from ferromagnetic resonance （FMR） that is self-biased by strong shape and mag- netocrystaUine anisotropy fields. Around the FMR frequency the specimen of the ferrite rods exhibits very high absorbance and the FMR frequency can be tuned by the rod dimension. In addition to the high absorbance and the wide tunable absorption band, the microwave ab- sorber has another advantage of light weight due to the use of the ferrite rods instead of ferrite slabs.

关键词： hexagonal ferfite microwave materials microwave absorbers cobalt compounds ferromagnetic resonance

Highly Porous Amidoximed Carbon Nanofibers Supported Palladium（0） Nanoparticle Catalyzed Heck Reaction

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Chemical Research in Chinese Universities 2015年第6期31卷 1072-1077页

作者： MENG Qingrun bai jie GUO Shoujun LI Chunping Chemical Engineering College Inner Mongolia University of Technology Hohhot 010051 P. R. China

Highly porous amidoximed carbon nanofibers（AOCNFs）, which were fabricated via a conventional elec- trospinning technique followed by chemically modification, impregnation-reduction and carbonization process, had been used for the immobilization of palladium nanoparticles（Pd NPs） catalyst. During the carbonization process, po- lystyrene（PS） was selectively decomposed from bicomponent fibers, generating porous fibers. Fourier transform infrared spectroscopy（FTIR） result revealed the functional groups on PAN-PS fibers（PAN=polyacrylonitrile）, AOPAN-PS fibers and AOCNFs; scanning electron microscopy（SEM） was used to observe the morphology of all stages of nanofibers; transmission electron microscopy（TEM） result gave the structure of through-hole morphology clearly visible and the dispersion ofPd NPs on the surface of nanofibers; and X-ray photoelectron spectra（XPS） con- firmed that Pd nanoparticles on the surface of AOCNFs was of the metallic state. Moreover, the as-prepared catalyst exhibited high catalytic activity and efficient recycle for Heck coupling reactions between iodobenzene and acrylates.

关键词： Pd nanoparticle Carbon nanofiber Heck reaction

Evidence of temperature-controlled dissolved inorganic nitrogen distribution in a shallow lake

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Journal of Environmental Sciences 2022年第12期34卷 105-114页

作者： Yan wen wenqiang Zhang Baoqing Shan jie Qu Research Center for Eco-Environmental Sciences Chinese Academy of SciencesBeijing 100085China University of Chinese Academy of Sciences Beijing 100049China

Dissolved inorganic nitrogen(DIN) plays an important role in aquatic ecosystems as an available source of nitrogen(N). Despite recent advances in our understanding of the effects of climate change on DIN in coastal waters, shallow high-latitude lakes exposed to large seasonal temperature differences have received limited research attention. Therefore,in the present study, baiyangdian Lake(BYDL) was selected as the study area, as a typical high latitude shallow lake in North China. Based on water and sediment samples collected in spring, summer and winter seasons, DIN accumulation in sedimentary pore water and DIN diffusion fluxes at the sediment-water interface were quantified under different temperature conditions. Correlation analysis was used to establish the effects of temperature on DIN concentration and diffusion in different media. Results show that the diffusion of DIN at the lake sediment-water interface exhibited a strongly positive relationship with temperature, suggesting that high temperature conditions lead to greater DIN release from sediments. Cold temperatures cause DIN accumulation in sedimentary pore water, providing sufficient substrate for N-related bacteria in the sediment under cold temperature conditions. Temperature controls the vertical distribution of DIN by affecting its migratory diffusion and transformation at the sediment-water interface. These findings are valuable for understanding the impact of climate change on the distribution of N in inland shallow lakes,especially in high latitude shallow lakes subjected to large seasonal temperature differences throughout the year.

关键词： Shallow lake Temperature Dissolved inorganic nitrogen Vertical distribution Diffusion flux

Dominant changes in the breast muscle lipid profiles of broiler chickens with wooden breast syndrome revealed by lipidomics analyses

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Journal of Animal Science and Biotechnology 2022年第6期13卷 1703-1713页

作者： Ranran Liu Fuli Kong Siyuan Xing Zhengxiao He Lu bai Jiahong Sun Xiaodong Tan Di Zhao Guiping Zhao jie wen Institute of Animal Sciences Chinese Academy of Agricultural SciencesState Key Laboratory of Animal NutritionKey Laboratory of Animal(Poultry)Genetics Breeding and ReproductionMinistry of AgricultureBeijingChina

Background: Chicken is the most consumed meat worldwide and the industry has been facing challenging myopathies. Wooden breast(WB), which is often accompanied by white striping(WS), is a serious myopathy adversely affecting meat quality of breast muscles. The underlying lipid metabolic mechanism of WB affected broilers is not fully ***: A total of 150 chickens of a white-feathered, fast-growing pure line were raised and used for the selection of WB, WB + WS and control chickens. The lipids of the breast muscle, liver, and serum from different chickens were extracted and measured using ultra performance liquid chromatography(UPLC) plus Q-Exactive Orbitrap tandem mass spectrometry. In the breast, 560 lipid molecules were identified. Compared to controls, 225/225 of 560 lipid molecules(40.2%) were identified with differential abundance(DA), including 92/100 significantly increased neutral lipids and 107/98 decreased phospholipids in the WB/WB + WS groups, respectively. The content of monounsaturated fatty acids(MUFA) was significantly higher, and the polyunsaturated fatty acids(PUFA) and saturated fatty acids(SFA) were significantly lower in the affected breasts. In the liver, 434 lipid molecules were identified, and 39/61 DA lipid molecules(6.7%/14.1%) were detected in the WB and WB + WS groups, respectively. In the serum, a total of 529 lipid molecules were identified and 4/44 DA lipid molecules(0.8%/8.3%) were detected in WB and WB + WS group, respectively. Compared to controls, the content of MUFAs in the serum and breast of the WB + WS group were both significantly increased, and the content of SFAs in two tissues were both significantly decreased. Only five lipid molecules were consistently increased in both liver and serum in WB + WS ***: We have found for the first time that the dominant lipid profile alterations occurred in the affected breast muscle. The relative abundance of 40.2% of lipid molecules were changed and is characteri

关键词： Broiler chicken Lipid profle Liver Serum Wooden breast

Evolution and Development Trend Prospect of Metal Milling Equipment

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Chinese Journal of Mechanical Engineering 2023年第2期36卷 1-15页

作者： jie wen Fugui Xie Xinjun Liu Yi Yue Department of Mechanical Engineering(DME) Tsinghua UniversityBeijing 100084China Beijing Key Lab of Precision/Ultra‑Precision Manufacturing Equipments and Control Tsinghua UniversityBeijing 100084China Beijing Spacecrafts Beijing 100094China

The world is currently undergoing profound changes which have never happened within the past *** competition in the technology and industry fields is becoming increasingly *** strategic competition of the major powers further focuses on the manufacturing *** countries such as the United States,Germany,and Japan have successively put forward strategic plans such as“re-industrialization”and“return of manufacturing industry”,aiming to seize the commanding heights of a new round of global high-end technology competition and expand international market *** at the historic intersection of a new round of scientific and technological revolution and China's accelerated high-quality development,the“14th Five-Year Plan”clearly pointed out that intelligent manufacturing is the main development trend to promote China's manufacturing to the medium-high end of the global value *** reflects the importance of advanced manufacturing for national strategic *** better grasp the development direction of advanced manufacturing equipment,the development process and current application status of manufacturing equipment are summarized,and thereafter the characteristics of manufacturing equipment in different development stages of the manufacturing industry are ***,the development trend of advanced milling equipment is prospected.

关键词： Intelligent manufacturing High-quality development Milling equipment Evolution and development trend

Effects of surface morphology on tribological properties of Arapaima gigas scales

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Friction 2024年第7期12卷 1469-1482页

作者： Shuaijun ZHANG Pengpeng bai Xiangli wen Chengwei wen Hui CAO Wanyou YANG Yu TIAN State Key Laboratory of Tribology in Advanced Equipment Department of Mechanical EngineeringTsinghua UniversityBeijing 100084China Key Laboratory of Bionic Engineering(Ministry of Education China)Jilin UniversityChangchun 130022China

The remarkable mechanical adaptability of arapaima(Arapaima gigas)scales has made them an important subject of ***,no research has been conducted into their tribological properties,which are crucial for the protectability and flexibility of *** this study,by combining morphological characterizations,friction experiments,and theoretical analyses,the relationship between the surface morphology and tribological properties of arapaima scales is *** results indicate that arapaima scales exhibit varying surface morphologies in different *** specifically,the exposed regions of scales feature grooves and a circulus,whereas the covered regions exhibit *** specific surface morphology of arapaima scales produces varying tribological properties across different regions and sliding *** unique tribological properties of arapaima scales influence the forces received from predator attacks and neighboring scales,directly influencing the arapaima’s protective *** study provides new insights into the mechanisms of natural flexible dermal armors,and it has potential applications in personal protective systems.

关键词： arapaima scales surface morphology tribological properties protectability

Numerical simulation on the seismic performance of retrofitted masonry walls based on the combined finite-discrete element method

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Earthquake Engineering and Engineering Vibration 2023年第3期22卷 777-805页

作者： Wu Biye Dai Junwu Jin Huan bai wen Chen Bowen Key Laboratory of Earthquake Engineering and Engineering Vibration Institute of Engineering MechanicsChina Earthquake AdministrationHarbin 150080China Key Laboratory of Earthquake Disaster Mitigation Ministry of Emergency ManagementHarbin 150080China Guangdong University of Petrochemical Technology Maoming 525000China

Due to the long construction life,improper design methods,brittle material properties and poor construction techniques,most existing masonry structures do not perform well during *** retrofitting method using an external steel-meshed mortar layer is widely used to retrofit existing masonry *** the seismic performance of masonry walls reinforced by an external steel-meshed mortar layer reasonably and effectively is a difficult subject in the research field of masonry *** on the combined finite-discrete elements method,the numerical models of retrofitted brick walls with four different masonry mortar strengths by an external mortar layer are *** shear strength of mortar and the contact between the retrofitted mortar layer and the brick blocks are discussed in *** failure patterns and load-displacement curves of the retrofitted brick walls were obtained by applying low cycle reciprocating loads to the numerical model,and the bearing capacity and the failure mechanism of the retrofitted walls were obtained by comparing the failure patterns,ultimate bearing capacity,deformability and other aspects with the *** study provides a basis for improving the seismic strengthening design method of masonry structures and helps to better assess the seismic performance of masonry structures after retrofitting.

关键词： masonry wall external steel-meshed mortar layer combined finite-discrete element method hysteretic curve ultimate bearing capacity