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A novel high-strength Al-La-Mg-Mn alloy for selective laser melting

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Journal of Materials Science & Technology 2023年第6期137卷 205-214页

作者： Xinkui Zhang Liejun Li zhi wang Hanlin peng Jixiang Gao Zhengwu peng Guangdong Key Laboratory for Advanced Metallic Materials Processing South China University of TechnologyGuangzhou 510640China Guangdong Provincial Key Laboratory of Advanced Welding Technology China-Ukraine Belt and Road Joint Laboratory on Materials Joining and Advanced ManufacturingChina-Ukraine Institute of WeldingGuangdong Academy of SciencesGuangzhou 510650China Guangdong Polytechnic Normal University Guangzhou 510635China

Developing high-strength Al-(La,Ce)alloys for additive manufacturing(AM)would entail considerable economic benefits.In this work,a novel near-eutectic Al-La alloy containing 5.50 wt.%Mg and 0.60 wt.%Mn was designed and fabricated via selective laser melting(SLM).Submicron Al_(11)La_(3)intermetallics with 3D continuous cellular-dendritic and granular morphologies were observed at the interior and boundary of the melt pool,respectively.Interestingly,these intermetallics are hierarchical and contained numerous Al_(6)Mn and Mg_(2)Si secondary nanoprecipitates.The as-fabricated alloy exhibited a tensile yield strength(YS)of 334 MPa and ultimate tensile strength(UTS)of 588 MPa at room temperature,which is the high-est UTS reported for Al-(La,Ce)alloys with an appreciable failure strain of∼6.4%.The 3D continuous cellular dendritic intermetallic and high Mg content afford significant strengthening and work harden-ing ability.In addition,the hierarchical feature of the intermetallics generated additional microcracks to coordinate the deformation.

关键词： Selective laser melting Al-La alloys 3D continuous structure Hierarchical precipitate High strength

Research and application of the angular rolling technology for plate mill

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Advances in Manufacturing 2023年第3期11卷 462-476页

作者： zhi-Jie Jiao Jun-Yi Luo zhi-Qiang wang zhi-peng Xu Chun-Yu He Zhong Zhao State Key Laboratory of Rolling and Automation Northeastern UniversityShenyang 110819People's Republic of China

Angular rolling technology can overcome the size limitation of plate mill equipment and product heavy steel plate with large unit weight or improve the production efficiency of small width spreading ratio product.With the DEFORM software,the numerical simulation study of the angular rolling process was carried out,and the relation laws of the width,rolling force and strain of the rolled piece under different angular rolling process conditions were obtained.The simulation results show that with the rotation angle increasing,the width of the rolled piece increases.Comparing with the conventional rolling process,the rolling force changes gradually during the biting and throwing stage of the angular rolling pass.With the rotation angle increasing,both the equivalent strains in the thickness direction and in the width direction gradually increase.According to the pattern and dimension's changing formula in the double-pass angular rolling process,the prediction model of angle,reduction and width spreading is built.The opening value of side guide is set for the rotation angle controlling.For one 5000 mm heavy plate mill,the automation control system was modified,and the angular rolling technology was applied online.The absolute deviation of target width does not exceed±20 mm and the relative deviation does not exceed 1%.The large unit weight plate that cannot be rolled with traditional process,can be produced now,and the annual output increases by 10000 t.

关键词： Plate mill Angular rolling Numerical simulation Width spreading Prediction model Online application

Research and development of advanced structured packing in a rotating packed bed

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Chinese Journal of Chemical Engineering 2022年第9期35卷 178-186页

作者： zhi-Guo Yuan Yu-Xia wang You-zhi Liu Dan wang Wei-Zhou Jiao peng-Fei Liang Shanxi Province Key Laboratory of Higee-Oriented Chemical Engineering North University of ChinaTaiyuan 030051China

As the core component of the rotating packing bed,packing is a place for efficient gas–liquid mixing and mass transfer.In this paper,a 3D structured packing composed of a mesh structure and a support structure was designed.The mesh structure is a ring-shaped mesh surrounded by triangular meshes,which is stable in structure and can achieve a high degree of dispersion and aggregation of the liquid phase.The support structure is composed of ring-shaped structural units arranged at a certain angle along the axial direction,which can enhance the turbulence of the airflow while constructing regular gas-phase channels.Circumferential steel meshes of different diameters and supporting structures are alternately combined to form 3D packing,which is loaded in a layered cross-flow rotating packing bed.The results show that under the same operating conditions,the mass transfer performance of 3D packing and wire mesh packing are equivalent,and both are better than pall ring packing.Moreover,the pressure drop of 3D packing is significantly lower than that of pall ring packing and wire mesh packing.The design and implementation of packing the development presented in this paper can be used to develop special structured packing for rotating bed,which can further improve the performance of rotating packed bed(RPB).

关键词： Rotating packed bed 3D printed packing 3D modeling Mass transfer Pressure drop Gas–liquid channel

Colorectal cancer screening:The value of early detection and modern challenges

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World Journal of Gastroenterology 2024年第20期30卷 2726-2730页

作者： Jian Li zhi-peng Li Wen-Jie Ruan Wei wang Department of Interventional Oncology Municipal Hospital Affiliated to Taizhou UniversityTaizhou 318000Zhejiang ProvinceChina School of Medicine Taizhou UniversityTaizhou 318000Zhejiang ProvinceChina

The screening of colorectal cancer(CRC)is pivotal for both the prevention and treatment of this disease,significantly improving early-stage tumor detection rates.This advancement not only boosts survival rates and quality of life for patients but also reduces the costs associated with treatment.However,the adoption of CRC screening methods faces numerous challenges,including the technical limitations of both noninvasive and invasive methods in terms of sensitivity and specificity.Moreover,socioeconomic factors such as regional disparities,economic conditions,and varying levels of awareness affect screening uptake.The coronavirus disease 2019 pandemic further intensified these challenges,leading to reduced screening participation and increased waiting periods.Additionally,the growing prevalence of early-onset CRC necessitates innovative screening approaches.In response,research into new methodologies,including artificial intelligence-based systems,aims to improve the precision and accessibility of screening.Proactive measures by governments and health organizations to enhance CRC screening efforts are underway,including increased advocacy,improved service delivery,and international cooperation.The role of technological innovation and global health collaboration in advancing CRC screening is undeniable.Technologies such as artificial intelligence and gene sequencing are set to revolutionize CRC screening,making a significant impact on the fight against this disease.Given the rise in early-onset CRC,it is crucial for screening strategies to continually evolve,ensuring their effectiveness and applicability.

关键词： Colorectal cancer Early detection Economic implications Noninvasive tests Quality of life Survival rates Therapeutic modalities Technical challenges

Difluoroalkylative carbonylation of alkenes to access carbonyl difluoro-containing heterocycles:convenient synthesis of gemigliptin

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Science China Chemistry 2023年第1期66卷 139-146页

作者： zhi-peng Bao Youcan Zhang Le-Cheng wang Xiao-Feng Wu Dalian National Laboratory for Clean Energy Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023China Leibniz-Institut für Katalyse e.V.Albert-Einstein-Straße 29a Rostock 18059Germany

Fluorinated heterocycles play a vital role in pharmaceutical and agrochemical industries.Hence,rapid and efficient construction of fluorinated heterocycles remains highly demanded.Herein,a difluoroalkylative carbonylative cyclization of unactivated alkenes and ethylene gas enabled by palladium catalysis has been developed for the first time toward the synthesis ofα-carbonyl difluoro-modified glutarimides.This procedure can also be applied to the synthesis of Ge Migliptin which is a medicine approved for the treatment of type 2 diabetes mellitus.

关键词： difluoroalkylative carbonylative unactivated alkenes ethylene gas heterocycles

Entropy production by dissipation effects and characteristic vortex evolution in a rocket turbopump

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Journal of Hydrodynamics 2023年第5期35卷 993-1007页

作者： De-you Li Jia-qi Zhu Rui-yi Zhang Yi Zhang zhi-peng Li Hong-jie wang zhi-peng Ren School of Energy Science and Engineering Harbin Institute of TechnologyHarbin150001China School of Astronautics Harbin Institute of TechnologyHarbin150001China

The relationship between entropy production and vortex evolution affects the efficiency and stability of rotating machinery.This study investigated the energy characteristics of a rocket turbopump and revealed the correlated mechanisms of the entropy production rate using the dissipation effects and characteristic vortex evolution.For the first time,direct and turbulent dissipation and rigid and shear vorticity decomposition methods were utilized to analyze the correlation between flow loss and characteristic vorticities in rotating machinery.With an increase in the flow rate,the hydraulic losses of the dissipation effects and wall decreased by 60%and 38.3%,respectively,and the proportions of the input energy decreased(from 13%to 8%)and remained stable(8%),respectively.The local direct dissipative entropy production(DDEP)in the inducer-impeller is strongly related to shear entropy,and the correlated effect of total enstrophy on DDEP is weaker than that of shear vorticity,indicating that rigid enstrophy suppresses direct dissipation.The correlation between turbulent dissipation and rigid enstrophy was significantly weaker in the static flow passage of the turbopump owing to the weak rigid rotational effect.The correlation between the rigid entropy and local turbulent dissipative entropy production(TDEP)gradually increased with increasing flow rate,reaching a medium correlation(the maximal correlated degree in the turbopump)and exhibiting rigid rotation effects on the hydraulic loss.Moreover,the flow rate significantly affected the correlation(except for the diffuser),and the two characteristic vorticities reached a maximum at the designed flow rate owing to optimal efficiency and minimum hydraulic loss.

关键词： Rocket turbopump hydraulic loss dissipation entropy production vorticity decomposition Liutex

Electric field manipulation of magnetic skyrmions

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Rare Metals 2022年第12期41卷 4000-4014页

作者： Ya-Dong wang zhi-Jian Wei Hao-Ran Tu Chen-Hui Zhang zhi-peng Hou Guangdong Provincial Key Laboratory of Optical Information Material and Technology&Institute for Advanced Materials South China Academy of Advanced OptoelectronicsSouth China Normal UniversityGuangzhou 510006China Dongguan University of Technology Dongguan 523808China Physical Science and Engineering Division(PSE) King Abdullah University of Science and Technology(KAUST)Thuwal 23955-6900Saudi Arabia

Magnetic skyrmions are vortex-like swirling spin textures that are promising candidates for carrying information bits in future magnetic memories or logic circuits.To build skyrmionic devices,researchers must electrically manipulate magnetic skyrmions to enable easy integration into modern semiconductor technology.This operation generally uses a spin-polarized current,which unavoidably causes high energy dissipation and Joule heating.Thus,the electric-field strategy is a hopeful alternative for electrically manipulating the skyrmions due to the strategy’s negligible Joule heating and low energy cost.In this review,we systematically summarize the theoretical and experimental development of the electricalfield manipulation of magnetic skyrmions over the past decade.We review the following magnetic systems and physical mechanisms:(ⅰ)ultra-thin multilayer films with accumulation and release of interfacial charge,(ⅱ)singlephase multiferroic material with magneto-electric coupling,(ⅲ)ferromagnetic/ferroelectric(FM/FE)multiferroic heterostructure with magneto-elastic coupling.Finally,we consider future developmental trends in the electric-field manipulation of magnetic skyrmions and other topological magnetic domain structures.

关键词： Magnetic skyrmion Electric field Low energy cost Dzyaloshinskii-Moriya interaction(DMI)

Characterization of the microbial community response to replant diseases in peach orchards

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Journal of Integrative Agriculture 2023年第4期22卷 1082-1092页

作者： LI Wei-hua CHEN peng wang Yu-zhu LIU Qi-zhi Laboratory of Entomology and Nematology College of Plant ProtectionChina Agricultural UniversityBeijing 100193P.R.China State Key Laboratory of Integrated Management of Pest Insects and Rodents Institute of ZoologyChinese Academy of SciencesBeijing 100101P.R.China Key Laboratory of Natural Enemies Insects of Ministry of Agriculture and Rural Affairs Shandong Provincial Engineering Technology Research Center on Biocontrol of Crop Diseases and Insect PestInstitute of Plant ProtectionShandong Academy of Agricultural SciencesJinan 250100P.R.China Institute of Forestry and Pomology Beijing Academy of Agriculture and Forestry SciencesBeijing 100093P.R.China

This study attempted to monitor the development of microbial communities and reveal the correlation between the soil microbial community and soil nutrient factors over different years following the replanting of peach trees.The replanted soil(RS)and nonreplanted soil(NRS)were collected from peach orchards with different growth years(1,3,5,7,9,11,and 13 years)in the same region.The soil bacterial and fungal community diversities were analyzed by high-throughput sequencing technology.Redundancy analysis(RDA)was used to show the correlation between the soil microbial community and environmental variables.The alpha diversities of the bacterial and fungal communities indicated that RS contained a higher abundance of bacterial and fungal operational taxonomic units(OTUs)than NRS.NMDS and ANOSIM analyses showed that the soil bacterial and fungal communities were significantly(P3.0).In addition,the soil nutrient contents were lower in RS than in NRS in the early stage(1–5 years),and the RDA showed that bacterial and fungal phyla are closely associated with environmental variables,including the potential of hydrogen(pH),ammonium nitrogen(AN),available phosphorus(AP)and available potassium(AK).These results lead to a deeper understanding of the microbial responses to replanting in peach orchards.

关键词： replant disease complex syndrome microbial community high-throughput sequencing environmental variables

Identification of candidate piRNAs in the gonads of Paralichthys olivaceus (Japanese flounder)

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Zoological Research 2016年第5期37卷 301-306页

作者： Chun-Lei wang Zhi-Peng Wang Jia-Qi wang Ming-You Li Xiao-Wu CHEN Key Laboratory of Exploration and Utilization of Aquatic Genetic Resources Ministry of EducationShanghai Ocean UniversityShanghai 201306China

Piwi-interacting RNA （piRNA） plays an important role in the gonadal development and maintenance of Teleostei. In this study, piRNA libraries derived from the adult gonads of Japanese flounder （Paralichthys ofivaceus） were generated using next-generation sequencing technology. Using zebrafish piRNAs as a reference, 5 865 unique candidate piRNAs were identified; 289 candidate piRNA clusters （PRCs） were generated from the above piRNAs. Among the isolated candidate PRCs, a total of 38 ovary-specific, 45 ovary-bias, 24 testis-specific, and 131 testis-bias PRCs were found. The relative expression levels of seven PRCs were validated through quantitative reverse transcription-polymerase chain reaction. The results of this study will help facilitate exploration of the development and maintenance of the phenotypic sex mechanism in P. olivaceus.

关键词： Paralichthys olivaceus Ovary Testis piRNA