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journal of Iron and steel Research International 2024年第6期31卷 1502-1513页

作者： bo-lin Yang Chang-liu Kuang Zheng-long liu Chao Yu Cheng-ji Deng jun Ding The state Key Laboratory of Refractories and Metallurgy Wuhan University of Science and TechnologyWuhan 430081HubeiChina

Zrb_(2)-based ceramic composites were prepared by spark plasma sintering using Zrb_(2) powder prepared by molten salt method as raw material and siC and nano-graphite as *** effects of nano-graphite addition on the physical properties and oxidation resistance of Zrb_(2)-based ceramic samples were *** results show that the addition of an appropriate amount of nano-graphite can effectively improve the density of Zrb_(2)-based ceramic composites and improve the physical properties of the *** flexural strength of the ceramic sample with 8 vol.%nano-graphite reached 418.54 MPa,which was 53.14% higher than that of Zrb_(2)-siC ceramic material(273.31 MPa),and its oxidation resistance was also significantly *** demonstrats that the addition of an appropriate amount of nano-graphite can effectively improve the physical properties and oxidation resistance of Zrb_(2)-siC ceramic *** prolonging its service life in application and promoting the development of Zrb_(2)-based ceramic composites,it is of great significance for clean steel smelting.

关键词： Zrb_(2)-siC-graphite electrode ceramic Zrb_(2)-based ceramic composite Nano-graphite Physical property Oxidation resistance

saliency-guided meta-hallucinator for few-shot learning

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science China(Information sciences) 2024年第10期67卷 189-210页

作者： Hongguang ZHANG Chun liu jiandong WANG linru MA Piotr KONIUsZ Philip H.s.TORR lin YANG systems Engineering Institute Academy of Military Sciences Data61 Commonwealth Scientific and Industrial Research Organisation Australian National University Oxford University

Learning novel object concepts from limited samples remains a considerable challenge in deep learning. The main directions for improving the few-shot learning models include(i) designing a stronger backbone,(ii) designing a powerful(dynamic) meta-classifier, and(iii) using a larger pre-training set obtained by generating or hallucinating additional samples from the small scale dataset. In this paper, we focus on item(iii) and present a novel meta-hallucination strategy. Presently, most image generators are based on a generative network(i.e., GAN) that generates new samples from the captured distribution of images. However, such networks require numerous annotated samples for training. In contrast, we propose a novel saliency-based end-to-end meta-hallucinator, where a saliency detector produces foregrounds and backgrounds of support images. such images are fed into a two-stream network to hallucinate feature samples directly in the feature space by mixing foreground and background feature samples. Then, we propose several novel mixing strategies that improve the quality and diversity of hallucinated feature ***, as not all saliency maps are meaningful or high quality, we further introduce a meta-hallucination controller that decides which foreground feature samples should participate in mixing with backgrounds. To our knowledge, we are the first to leverage saliency detection for few-shot learning. Our proposed network achieves state-of-the-art results on publicly available few-shot image classification and anomaly detection benchmarks, and outperforms competing sample mixing strategies such as the so-called Manifold Mixup.

关键词： few-shot learning saliency detection object recognition anomaly detection computer vision

Azobenzene-based ultrathin peptoid nanoribbons for the potential on highly efficient artificial light-harvesting

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science China Chemistry 2024年第5期67卷 1680-1686页

作者： Zichao sun lingrong Zhu jingze liu Fan liu Pengchao Wu Pengliang sui Haibao jin shaoliang lin shanghai Key Laboratory of Advance Polymeric Materials Frontiers Science Center for Materiobiology and Dynamic ChemistrySchool of Materials Science and EngineeringEast China University of Science and TechnologyShanghai 200237China

The development of artificial light-harvesting systems based on long-range ordered ultrathin organic nanomaterials(i.e., below3 nm), which were assembled from stimuli-responsive sequence-controlled biomimetic polymers, remains challenging. Herein,we report the self-assembly of azobenzene-containing amphiphilic ternary alternating peptoids to construct photo-responsive ultrathin peptoids nanoribbons(UTPNRs) with a thickness of ~2.3 nm and the length in several micrometers. The pendants hydrophobic conjugate stacking mechanism explained the formation of one-dimensional ultrathin nanostructures, whose thickness was highly dependent on the length of side groups. The photo-isomerization of azobenzene moiety endowed the aggregates with a reversible morphology transformation from UTPNRs to spherical micelles(46.5 nm), upon the alternative irradiation with ultraviolet and visible light. Donor of 4-(2-hydroxyethylamino)-7-nitro-2,1,3-benzoxadiazole(NbD) and acceptor of rhodamine b(Rb) were introduced onto the hydrophobic and hydrophilic regions, respectively, to generate photocontrollable artificial light-harvesting systems. Compared with the spheres-based systems, the obtained NbD-UTPNRs@Rb composite proved a higher energy transfer efficiency(90.6%) and a lower requirement of Rb acceptors in water. A proof-ofconcept use as fluorescent writable ink demonstrated the potential of UTPNRs on information encryption.

关键词： azobenzene-based peptoid ultrathin nanoribbon photo-responsive light-harvesting information encryption

Extracellular vesicles and angiotensin-converting enzyme 2 in COVID-19 disease

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bIOCELL 2024年第1期48卷 1-8页

作者： YU liu RObERT j.KAsPER NATALIE j.s.CHOI Department of Family and Community Medicine Northwestern University Feinberg School of MedicineChicagoIllinois

Extracellular vesicles(EVs)are membranous vesicular structures released from almost all eukaryotic cell types under different physiological or pathological *** evidence demonstrates that EVs can serve as mediators of intercellular communication between donor and recipient cells or microorganism-infected and noninfected *** disease 2019(COVID-19)disease is caused by infection of the severe acute respiratory syndrome coronavirus 2(sARs-CoV-2)of host cells in the respiratory system and various extra-pulmonary tissue/organs,resulting in complications of multiple organ *** the cell surface receptor,angiotensin-converting enzyme 2(ACE2)mediates cellular entry of sARs-CoV-2 into the host cells in patients with *** studies have found that ACE2 can be released with EVs,which have been shown to interfere with the entry of the virus into host cells and thus may be involved in COVID-19 *** addition,ACE2,neprilysin(NEP),and thimet oligopeptidase(TOP)are the key enzymes that regulate angiotensin metabolism by converting angiotensin II or angiotensin I to angiotensin 1-7,the latter of which has protective effects in counterbalancing the harmful effects of angiotensin II in COVID-19 *** review summarizes the recent research progress regarding EV-associated ACE2,NEP,and TOP and the perspectives of their potential involvement in the pathophysiology of COVID-19 disease.

关键词： Extracellular vesicles COVID-19 Angiotensin converting enzyme 2 Thimet oligopeptidase

Fabrication of bio-inspired superamphiphobic Aluminum Alloy surface with Oil-triggered Wenzel-slippery Transition via Femtosecond Laser

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journal of bionic Engineering 2024年第3期21卷 1375-1387页

作者： Weijian liu Feng Guan Fulin Zhang Chenrui Wang Wei Zheng Lu Zhai Zhaohua lin Chunbao liu AVIC shenyang Aircraft Corporation Shenyang110000China school of Mechanical and Aerospace Engineering Jilin UniversityChangchun130022China

surface-tension-confined microfluidic devices are platforms for manipulating 2D droplets based on patterned surfaces with special *** have great potential for various applications,but are still in the early stages of development and face some challenges that need to be *** study,inspired by the Wenzel and slippery transition of rose petal,develops a Patterned Oil-triggered Wenzel-slippery surface(POWs)to examine the microfluidic devices.A laser-chemical composite method is established to fabricate POWss,which take rose-petal-like microstructures as wettability pattern and a superamphiphobic surface as the *** prepared POWss switched between high adhesion superhydrophobic state and the slippery liquid-infused surface state through adding or removing the lubricant *** the high adhesion superhydrophobic state,the droplets can be sticked on the *** the slippery liquid-infused state,the droplet can slide along the wettability pattern as the designed route.A POWs-based droplet reactor is further constructed,on which,the droplets can be remotely controlled to move,mix and react,as *** a POWs,which manipulates droplets with surface tension controlled by the switchable wettability patterns,would be a promising candidate to construct multiple surface-tension-confined microfluidic *** addition,the fabrication technique and design principle proposed here may aid the development of various field related to the bio-inspired surfaces,such as water collection,desalination and high throughput analysis,etc.

关键词： biomaterials bio-inspired surface Oil-triggered wenzel-slippery transition superhydrophobicity Femtosecondlaser

Constructing high-toughness polyimide binder with robust polarity and ion-conductive mechanisms ensuring long-term operational stability of silicon-based anodes

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journal of Energy Chemistry 2024年第6期93卷 580-591,I0014页

作者： Yongjun Kang Nanxi Dong Fangzhou liu Daolei lin bingxue liu Guofeng Tian shengli Qi Dezhen Wu state Key Laboratory of Chemical Resource Engineering Beijing University of Chemical TechnologyBeijing 100029China ENFI R&D Institute China ENFI Engineering CorporationBeijing 100038China China Automotive battery Research Institute Co. Ltd.Beijing 101407China Changzhou Institute of Advanced Materials Beijing University of Chemical TechnologyChangzhou 213164JiangsuChina

silicon-based materials have demonstrated remarkable potential in high-energy-density batteries owing to their high theoretical ***,the significant volume expansion of silicon seriously hinders its utilization as a lithium-ion ***,a functionalized high-toughness polyimide(PDMI) is synthesized by copolymerizing the 4,4'-Oxydiphthalic anhydride(ODPA) with 4,4'-oxydianiline(ODA),2,3-diaminobenzoic acid(DAbA),and 1,3-bis(3-aminopropyl)-tetramethyl disiloxane(DMs).The combination of rigid benzene rings and flexible oxygen groups(-O-) in the PDMI molecular chain via a rigidness/softness coupling mechanism contributes to high *** plentiful polar carboxyl(-COOH) groups establish robust bonding *** ionic transport is achieved by incorporating the flexible siloxane segment(si-O-si),which imparts high molecular chain motility and augments free volume holes to facilitate lithium-ion transport(9.8 × 10^(-10) cm^(2) s^(-1) vs.16 × 10^(-10) cm^(2) s~(-1)).As expected,the siO_x@PDMI-1.5 electrode delivers brilliant long-term cycle performance with a remarkable capacity retention of 85% over 500 cycles at 1.3 A g^(-1).The well-designed functionalized polyimide also significantly enhances the electrochemical properties of si nanoparticles ***,the assembled siO_x@PDMI-1.5/NCM811 full cell delivers a high retention of 80% after 100 *** perspective of the binder design strategy based on polyimide modification delivers a novel path toward high-capacity electrodes for high-energy-density batteries.

关键词： Polyimide binder High toughness Robust ionic transport silicon-based anodes Lithium-ion batteries

Migration mechanism of atrazine in the simulated lake icing process at different freezing temperatures based on density function theory

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journal of Environmental sciences 2024年第10期144卷 45-54页

作者： Yan Zhang Hao lin Aixin Yu Xiaozhuang Wang Yucan liu Tongshuai liu Chen Zhao Rui Mei school of Civil Engineering Yantai UniversityYantai 264005China

Atrazine causes concern due to its resistant to biodegradation and could be accumulated in aquatic organisms,causing pollution in *** study measured the concentration of atrazine in ice and the water under ice through a simulated icing experiment and calculated the distribution coefficient K to characterize its migration ability in the freezing ***,density functional theory(DFT)calculations were employed to expatiate the migration law of atrazine during icing *** to the results,it could release more energy into the environment when atrazine staying in water phase(-15.077 kcal/mol)than staying in ice phase(-14.388 kcal/mol),therefore it was beneficial for the migration of atrazine from ice to *** explains that during the freezing process,the concentration of atrazine in the ice was lower than that in the *** calculations indicated thatwhen the temperature decreases from268 to 248 K,the internal energy contribution of the compound of atrazine and ice molecule(water cluster)decreases at the same vibrational frequency,resulting in an increase in the free energy difference of the compound from-167.946 to-165.390 kcal/*** demonstrated the diminished migratory capacity of *** study revealed the environmental behavior of atrazine during lake freezing,which was beneficial for the management of atrazine and other pollutants during freezing and environmental protection.

关键词： Density functional theory(DFT) Icing process Atrazine Migration behavior Free energy

Confined Mn^(2+) enables effective aerobic oxidation catalysis

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science China Chemistry 2024年第5期67卷 1545-1553页

作者： Desheng Yuan sicong Ma Xiao Kong Chi Zhang lin Chen Chengsheng Yang Lihua Wang Zhen liu lin Ye Yongmei liu Rui Ma Zhi-Pan liu Yifeng Zhu Yong Cao Xinhe bao Department of Chemical Physics University of Science and Technology of ChinaHefei 230026China Department of Chemistry Shanghai Key Laboratory of Molecular Catalysis and Innovative MaterialsCollaborative Innovation Center of Chemistry for Energy MaterialsFudan UniversityShanghai 200438China Key Laboratory of synthetic and self-Assembly Chemistry for Organic Functional Molecules Shanghai Institute of Organic ChemistryChinese Academy of SciencesShanghai 200032China school of Materials and Chemistry University of Shanghai for Science and TechnologyShanghai 200093China shanghai synchrotron Radiation Facility Shanghai Advanced Research InstituteChinese Academy of SciencesShanghai 201204China Institute of Advanced Fluorine-Containing Materials Zhejiang Normal UniversityJinhua 321004China state Key Laboratory of Catalysis National Laboratory for Clean EnergyCollaborative Innovation Center of Chemistry for Energy MaterialsDalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023China

Effective and mild activation of O_(2) is essential but challenging for aerobic oxidation. In heterogeneous catalysis, high-valence manganese oxide(e.g., +4) is known to be active for the oxidation, whereas divalent MnO is ineffective due to its limited capacity to supply surface oxygen and its thermodynamically unstable structure when binding O_(2) in reaction conditions. Inspired by natural enzymes that rely on divalent Mn^(2+), we discovered that confining Mn^(2+) onto the Mn_(2)O_(3) surface through a dedicated calcination process creates highly active catalysts for the aerobic oxidation of 5-hydroxymethylfurfural, benzyl alcohol, and *** Mn_(2)O_(3)-confined Mn^(2+) is undercoordinated and efficiently mediates O_(2) activation, resulting in 2–3 orders of magnitude higher activity than Mn_(2)O_(3) alone. Through low-temperature infrared spectroscopy, we distinguished low-content Mn^(2+) sites at Mn_(2)O_(3) surface, which are difficult to be differentiated by X-ray photoelectron spectroscopy. The combination of in-situ energydispersive X-ray absorption spectroscopy and X-ray diffraction further provides insights into the formation of the newly identified active Mn^(2+) sites. by optimizing the calcination step, we were able to increase the catalytic activity threefold *** finding offers promising frontiers for exploring active oxidation catalysts by utilizing the confinement of Mn^(2+)and oftenignored calcination skills.

关键词： confinement catalysis manganese oxide aerobic oxidation divalent Mn^(2+) operando spectroscopies

Advances in memristor based artificial neuron fabrication-materials,models,and applications

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International journal of Extreme Manufacturing 2024年第1期6卷 27-50页

作者： jingyao bian Zhiyong liu Ye Tao Zhongqiang Wang Xiaoning Zhao Ya lin Haiyang Xu Yichun liu Key Laboratory for UV Light-Emitting Materials and Technology(Northeast Normal University) Ministry of Education5268 Renmin StreetChangchunPeople’s Republic of China

spiking neural network(sNN),widely known as the third-generation neural network,has been frequently investigated due to its excellent spatiotemporal information processing capability,high biological plausibility,and low energy consumption *** to the working mechanism of human brain,the sNN system transmits information through the spiking action of ***,artificial neurons are critical building blocks for constructing sNN in *** are drawing growing attention due to low consumption,high speed,and nonlinearity characteristics,which are recently introduced to mimic the functions of biological *** have proposed multifarious memristive materials including organic materials,inorganic materials,or even two-dimensional *** advantage of the unique electrical behavior of these materials,several neuron models are successfully implemented,such as Hodgkin–Huxley model,leaky integrate-and-fire model and integrate-and-fire *** this review,the recent reports of artificial neurons based on memristive devices are *** addition,we highlight the models and applications through combining artificial neuronal devices with sensors or other electronic ***,the future challenges and outlooks of memristor-based artificial neurons are discussed,and the development of hardware implementation of brain-like intelligence system based on sNN is also prospected.

关键词： artificial neuron memristor memristive materials neuron model micro-nano manufacturing spiking neural network

Initial Experience of NIR-II Fluorescence Imaging-Guided surgery in Foot and Ankle surgery

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Engineering 2024年第9期40卷 19-27页

作者： Xiaoxiao Fan jie Yang Huwei Ni Qiming Xia Xiaolong liu Tianxiang Wu lin Li Paras N.Prasad Chao liu Hui lin jun Qian Department of General surgery Sir Run Run Shaw HospitalSchool of MedicineZhejiang UniversityHangzhou 310016China Centre for Optical and Electromagnetic Research&International Research Center for Advanced Photonics College of Optical Science and EngineeringZhejiang UniversityHangzhou 310058China Department of Orthopedics Sir Run Run Shaw HospitalSchool of MedicineZhejiang UniversityHangzhou 310016China Institute for Lasers Photonicsand BiophotonicsDepartment of ChemistryState University of New YorkBuffaloNY 14260-3000USA Zhejiang Engineering Research Center of Cognitive Healthcare Sir Run Run Shaw HospitalSchool of MedicineZhejiang UniversityHangzhou 310016China College of biomedical Engineering and Instrument science Zhejiang UniversityHangzhou 310027China

Optical imaging in the second near-infrared(NIR-II;900-1880 nm)window is currently a popular research topic in the field of biomedical *** study aimed to explore the application value of NIR-II fluorescence imaging in foot and ankle surgeries.A lab-established NIR-II fluorescence surgical navigation system was developed and used to navigate foot and ankle surgeries which enabled obtaining more high-spatial-frequency information and a higher signal-to-background ratio(sbR)in NIR-II fluorescence images compared to NIR-I fluorescence images;our result demonstrates that NIR-II imaging could provide higher-contrast and larger-depth images to *** types of clinical application scenarios(diabetic foot,calcaneal fracture,and lower extremity trauma)were included in this *** the NIR-II fluorescence imaging technique,we observed the ischemic region in the diabetic foot before morphological alterations,accurately determined the boundary of the ischemic region in the surgical incision,and fully assessed the blood supply condition of the ***-II fluorescence imaging can help surgeons precisely judge surgical margins,detect ischemic lesions early,and dynamically trace the perfusion *** believe that portable and reliable NIR-II fluorescence imaging equipment and additional functional fluorescent probes can play crucial roles in precision surgery.

关键词： second near-infrared fluorescence imaging Foot and ankle surgery Indocyanine green Imaging-guided surgery