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A Symmetric-Actuating linear Piezoceramic Ultrasonic Motor Capable of Producing a Scissoring Effect

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Research 2024年第1期2023卷 571-581页

作者： Zhanmiao Li Xingyu yi Rongqi zhu Zhonghui Yu Xiaoting Yuan MohammadJavad PourhosseiniAsl Shuxiang Dong School of Materials Science and Engineering Peking UniversityBeijing 100871China College of Mechatronics and Control Engineering and Institute for Advanced StudyShenzhen UniversityShenzhen 518051China

Conventionally,to produce a linear motion,one motor’s stator is employed to drive one runner moving forward or *** far,there is almost no report of one electromechanical motor or piezoelectric ultrasonic motor that can directly generate two symmetrical linear motions,while this function is desired for precise scissoring and grasping in the minimally invasive surgery ***,we report a brandnew symmetric-actuating linear piezoceramic ultrasonic motor capable of generating symmetrical linear motions of two outputs directly without additional mechanical transmission *** key component of the motor is an(2×3)arrayed piezoceramic bar stator operating in the coupled resonant mode of the first longitudinal(L_(1))and third bending(B_(3))modes,leading to symmetric elliptical vibration trajectories at its two ends.A pair of microsurgical scissors is used as the end-effector,demonstrating a very promising future for high-precision microsurgical operations.

关键词： field symmetric backward

Monascus purpureus M-32 fermented soybean meal improves the growth, immunity parameters, intestinal morphology, disease resistance, intestinal microbiota and metabolome in Pacific white shrimp(Litopenaeus vannamei)

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Animal Nutrition 2024年第2期17卷 283-296页

作者： Pan Wang Shanshan Wang Chuanzhong zhu Yunzhang Sun Qingpi Yan Ganfeng yi Fisheries College Jimei University Key Laboratory of Aquatic Functional Feed and Environmental Regulation of Fujian Province Fujian DBN Aquatic Sci.&Tech. Co. Ltd. Fantastic Victory(Shenzhen)Technological Innovation Group Co. Ltd.

This study was conducted to evaluate the effects of Monascus purpureus M-32 fermented soybean meal（MFSM） on growth, immunity, intestinal morphology, intestinal microbiota, and intestinal metabolome of Pacific white shrimp（Litopenaeus vannamei）. Four groups of diets were formulated, including control group（30% fish meal and 30% soybean meal [SBM] included in the basal diet） and three experimental groups which MFSM replaced 20%（MFSM20）, 40%（MFSM40）, and 60%（MFSM60） of SBM in control group, respectively. Results showed that the soluble proteins larger than 49 k Da in MFSM were almost completely degraded. Meanwhile, the crude protein, acid-soluble protein, and amino acid in MFSM were increased. The results of shrimp culture experiment showed that the replacement of SBM with MFSM decreased FCR（P < 0.001） and content of malondialdehyde（P = 0.007） in the experimental groups, and increased weight gain rate（P = 0.006）, specific growth rate（P = 0.002）, survival rate（P = 0.005）, intestinal villus height（P < 0.001）, myenteric thickness（P = 0.002）, the activities of superoxide dismutase（P = 0.002）, and lysozyme（P = 0.006） in experimental groups, as well as increased content of calcium(Ca2+) and phosphorus（■） in blood and muscle, and enhanced resistance to Vibrio parahaemolyticus infection. The gut microbiota of MFSM groups was significantly different from that of the control group,and the abundance of Actinobacteria and Verrucomicrobia increased significantly in the MFSM60 group,whereas Proteobacteria and Firmicutes decreased. Compared with the control group, there were significant changes in the levels of several intestinal metabolites in the MFSM60 group, including leukotriene C5, prostaglandin A1, taurochenodeoxycholic acid, carnosine, and itaconic acid. The fermentation of SBM by the strain M. purpureus M-32 has the potential to enhance the nutritional quality of SBM,promote the growth of L. vannamei, boost immune response, improve intestinal morphology and microbiota compos

关键词： Monascus purpureus Fermented soybean meal Litopenaeus vannamei Intestinal microbiota Metabolome

Degradation of iopamidol in the permanganate/sulfite process:Evolution of iodine species and effect on the subsequent formation of disinfection by-products

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Journal of Environmental Sciences 2024年第1期135卷 345-352页

作者： yimin lin Hongyu Dong Yating zhu Gongming Zhou Junlian Qiao Xiaohong Guan State Key Laboratory of Pollution Control and Resources Reuse College of Environmental Science and EngineeringTongji UniversityShanghai 200092China Department of Environmental Science School of Ecological and Environmental SciencesEast China Normal UniversityShanghai 200241China

Permanganate/sulfite(Mn(VII)/S(IV))process is a promising pre-oxidation technology for sequestering the emerging organic contaminants in drinking water treatment ***(IPM),a representative of iodinated X-ray contrast media,has been widely detected in water sources and has the risk of forming iodinated disinfection byproducts(I-DBPs)in water treatment *** this study,we investigated the evolution of iodine species during the IPM degradation by the Mn(VII)/S(IV)process and its effect on the subsequent formation of I-DBPs during chlorination at pH 7.0 and *** could be effectively degraded in the Mn(VII)/S(IV)process at environmentally relevant pH(pH 7.0 and 8.0).The results of quenching and competitive oxidation kinetic experiments revealed that SO^(·-)_(4)was the major reactive oxidizing species contributing to the degradation of IPM whereas the contributions of HO·and reactive manganese species were negligible in the Mn(VII)/S(IV)process.I–and IO–3were generated while no HOI was detected during the degradation of IPM in the Mn(VII)/S(IV)*** effects of IPM oxidation by Mn(VII)/S(IV)on the subsequent formation of chlorinated disinfection by-products(Cl-DBPs)during chlorination were related to the category of *** pre-oxidation of IPM by Mn(VII)/S(IV)resulted in the generation of I-DBPs during the disinfection process although no I-DBPs were detected if no pre-oxidation was *** finding of this study suggested that attention should be paid to the toxicity of DBPs when water containing iodinated organic contaminants is treated by Mn(VII)/S(IV)process or other pre-oxidation technologies.

关键词： Permanganate/sulfite Iopamidol Sulfate radical Iodinated disinfection byproducts Pre-oxidation

Designing unimolecular photoinitiator by installing NHPI esters along the TX backbone for acrylate photopolymerization and their applications in coatings and 3D printing

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Chinese Chemical Letters 2024年第7期35卷 417-421页

作者： yi zhu Jingyan Zhang Yuchao Zhang ying Chen Guanghui An Ren Liu Key Laboratory of Synthetic and Biological Colloids Ministry of EducationSchool of Chemical and Material EngineeringJiangnan UniversityWuxi 214122China International Research Center for Photoresponsive Molecules and Materials Jiangnan UniversityWuxi 214122China School of Chemistry and Materials Science Heilongjiang UniversityHarbin 150080China Scientific Experiment Center Hangzhou Institute of Medicine(HIM)Chinese Academy of SciencesHangzhou 310022China

Developing efficient and long wavelength sensitive unimolecular photoinitiators(PIs)is still facing a great *** this work,a series of thioxanthone-based N-hydroxyphthalimide esters(TX-NHPIEs)were synthesized by installing NHPIEs along the TX backbone and *** investigated TX-NHPIEs have a 60 nm redshift and demonstrate sterling initiating efficiency for free radical photopolymerization(FRP)under LED@450 nm light irradiation compared with the commercialized isopropylthioxanthone(ITX).Real-time1Hnuclear magnetic resonance(1H NMR),electron spin resonance(ESR),decarboxylation and gas chromatograph-mass spectrometer(GC–MS)experiments and density functional theory(DFT)reveal that TX-NHPIEs can generate one alkyl radical and one N-centered iminyl radical,which can initiate FRP directly and indirectly,*** other words,TX-NHPIEs absorb one photon and can generate two active radicals,which break through the limitations of common ***-NHPIE-Cpe demonstrates the highest initiating efficiency,and its application in coatings and 3D printing was also studied,indicating TX-NHPIEs have broad potential applications in photopolymerization processes.

关键词： Photopolymerization Photoinitiator Energy transfer Thioxanthone N-Hydroxyphthalimide ester

A Composite Transformer-Based Multi-Stage Defect Detection Architecture for Sewer Pipes

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Computers, Materials & Continua 2024年第1期78卷 435-451页

作者： Zifeng Yu Xianfeng Li Lianpeng Sun Jinjun zhu Jianxin lin School of Computer Science and Engineering Macao University of Science and TechnologyMacao999078China School of Environmental Science and Engineering Sun Yat-sen UniversityGuangzhou510275China Guangdong AIKE Environmental Science and Technology Co. Ltd.Zhongshan528400China

Urban sewer pipes are a vital infrastructure in modern cities,and their defects must be detected in time to prevent potential *** recent years,to relieve the manual efforts by human experts,models based on deep learning have been introduced to automatically identify potential ***,these models are insufficient in terms of dataset complexity,model versatility and *** work addresses these issues with amulti-stage defect detection architecture using a composite backbone Swin *** based on this architecture is trained using a more comprehensive dataset containingmore classes of *** ablation studies on the modules of combined backbone Swin Transformer,multi-stage detector,test-time data augmentation and model fusion,it is revealed that they all contribute to the improvement of detection accuracy from different *** model incorporating all these modules achieves the mean Average Precision(mAP)of 78.6% at an Intersection over Union(IoU)threshold of *** represents an improvement of 14.1% over the ResNet50 Faster Region-based Convolutional Neural Network(R-CNN)model and a 6.7% improvement over You Only Look Once version 6(YOLOv6)-large,the highest in the YOLO *** addition,for other defect detection models for sewer pipes,although direct comparison with themis infeasible due to the unavailability of their private datasets,our results are obtained from a more comprehensive dataset and have superior generalization capabilities.

关键词： Sewer pipe defect detection deep learning model optimization composite transformer

Optical Transient Source AT2021lfa:A Possible“Dirty Fireball”

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Research in Astronomy and Astrophysics 2024年第4期24卷 124-133页

作者： Xue-Mei Ye Da-Ming Wei yi-Ming zhu Zhi-Ping Jin Key Laboratory of Dark Matter and Space Astronomy Purple Mountain ObservatoryChinese Academy of SciencesNanjing 210023China School of Astronomy and Space Science University of Science and Technology of ChinaHefei 230026China National Astronomical Observatories/Nanjing Institute of Astronomical Optics&Technology Chinese Academy of SciencesNanjing 210042China CAS Key Laboratory of Astronomical Optics&Technology Nanjing Institute of Astronomical Optics&TechnologyNanjing 210042China

AT2021lfa,also known as ZTF21aayokph,was detected by the Zwicky Transient Facility on 2021 May 4,a 05:34:48 ***-up observations were conducted using a range of ground-based optical telescopes,as wel as Swift/XRT and VLA ***2021lfa is classified as an“orphan afterglow”candidate due to its rapid flux decline and its reddened color(g-r=0.17±0.14 mag).For an optical transient source without promp gamma-ray detection,one key point is to determine its burst *** we measure the burst time through fitting the initial bump feature of AT2021lfa and obtain its burst time as 2021 May 3,at 22:09:50 *** afterglowpy,we model the multi-band afterglow of AT2021lfa and find that the standard model canno reproduce the late radio observations *** that the microphysical parameters ε_(e),ε_(B)(the energy fraction given to electrons and magnetic field),andξN(the fraction of accelerated electrons)may vary with time we then model the afterglow of AT2021lfa taking into account the temporal evolution of the physical parameters ε_(e),ε^(B),and ξ_(N) and find in this case the multi-wavelength observations can be reproduced *** initial Lorentz factor of AT2021lfa can be estimated from the peak time of the early afterglow,which yields a value of about 18 suggesting that AT2021lfa should be classified as a“dirty fireball.”From the upper limit for the prompt emission energy of AT2021lfa,we obtain that the radiation efficiency is less than 0.02%,which is much smaller than that of ordinary gamma-ray bursts(GRBs).It is also interesting that the fitted values of jet angle and viewing angle are very large,θ_(c)~0.66 rad,θ_(v)~0.53 rad,which may lead to the low Lorentz factor and radiation *** compared with GRB afterglow samples,it is evident that the onset bump timescale of AT2021lfa satisfies the empirical relationships observed in GRB ***,the luminosity of AT2021lfa falls within the range of observations for GRB samples;howeve

关键词： gamma-rays:ISM methods:numerical radiation mechanisms:non-thermal

Astronomical Test with CMOS on the 60 cm Telescope at the Xinglong Observatory,NAOC

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Research in Astronomy and Astrophysics 2024年第5期24卷 85-102页

作者： Hai-Yang Mu Zhou Fan yi-Nan zhu Yu Zhang Hong Wu Key Laboratory of Optical Astronomy National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101People’s Republic of China School of Astronomy and Space Science University of Chinese Academy of SciencesBeijing 100049People’s Republic of China

This work shows details of an evaluation of an observational system comprising a complementary metal-oxidesemiconductor detector, 60 cm telescope and filter complement. The system’s photometric precision and differential photometric precision, and extinction coefficients were assessed through observations of Supersky flat fields, open clusters, standard stars and exoplanets. Photometry was precision achieved at the 0.02 mag level, with differential photometry of 0.004 mag precision. Extinction was found to agree with previous studies conducted at Xinglong Observatory. Ultimately, the results demonstrate this observing system is capable of precision scientific observations with a charge-coupled device across the optical wavelengths.

关键词： atmospheric effects-instrumentation detectors-techniques polarimetric-stars atmospheres-eclipses

Isocyanide-Based One-Pot Cascade Synthesis of 3-Acyl Isoindolinones

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Chinese Journal of Chemistry 2024年第3期42卷 259-263页

作者： Jia Liu yi-Ming zhu Xiao-Ping Xu Shun-Jun Ji Key Laboratory of Organic Synthesis of Jiangsu Province College of ChemistryChemical Engineering and Materials Science & Collaborative Innovation Center of Suzhou Nano Science and TechnologySoochow UniversitySuzhouJiangsu215123 China Suzhou Baolidi Functional Materials Research Institute SuzhouJiangsu215144 China

A series of 3-acyl-substituted isoindolinone derivatives were synthesized in a one-pot manner via the reaction of o-bromobenzaldehydes,isocyanides,and carboxylic acids in the presence of palladium catalyst and base. The reaction employing easily available starting materials features simple operation and high efficiency. The mechanistic study showed that the reaction might undergo 1) Pd-catalyzed [3+2] cyclization of o-bromobenzaldehyde with isocyanide and the re-insertion of another molecule of isocyanide,2) addition of carboxylic acid to in situ formed ketenimine followed by a rearrangement relay to give 3,3-diacyl-substituted isoindolinone derivative. Further transformations of the obtained products through decarbonylation could also be realized.

关键词： One-pot reaction Isocyanide Pd catalysis Rearrangement reaction Isoindolinone

Cooperative enhancement of mechanical and tribological properties through tailoring TiN transition interface in boron nitride nanosheets reinforced copper composites

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Rare Metals 2024年第10期43卷 5202-5215页

作者： Zhong-Hua Li Liang Liu Xin You Jian-Hong yi Rui Bao Ming-yi zhu Song Lu Jun-Jun Pai Faculty of Materials Science and Engineering Kunming University of Science and Technology Key Laboratory of Advanced Materials of Yunnan Province Kunming University of Science and Technology

Strengthening interface bonding between boron nitride nanosheets(BNNS) and copper matrix is an essential prerequisite for exploiting a new generation of copper matrix composites(CMCs) with high strength and wear resistance. Herein, BNNS/Cu composites were fabricated by the powder metallurgy route, matrix-alloying(adding 1.0 wt% Ti) strategy was adopted to improve the interfacial wettability and strengthen interface adhesion. A typical "sandwich"-like multiply interface structure involving TiN transition layers, BNNS and Cu matrix had been well constructed through the rational heat treatment(900℃for 120 min). Additionally, nano-sized TiB whisker was in situ formed in the vicinity of the interface, it had linked the BNNS-Cu-TiN multiply interface, which played a role of "threading the needle" and significantly strengthened the multi-interfaces bonding. This specific interface structure was finely characterized, and the formation mechanism of solid-state interfacial reaction feature was proposed. The results demonstrated that the ultimate tensile strength(UTS) of BNNS/Cu-(Ti)-900℃ increased from 248 to 530 MPa(increased by 114%), and the coefficient of friction(COF) decreased from 0.51 to 0.28 than pure Cu. This work highlights the importance of interface configuration design, which contributes to the development of CMCs with prominent comprehensive properties.

关键词： Boron nitride nanosheets Copper matrix composites Interface structure Mechanical and frictional properties