Preparation of PSFO and LPSFO nanofibers by electrospinning and their electronic transport and magnetic properties

Pr_(0.5)Sr_(0.5)FeO_(3)(PSFO)and La_(0.25)Pr_(0.25)Sr_(0.5)FeO_(3)(LPSFO)nanofibers are prepared by electrospinning followed by calcination,and their morphologies,microstructures,electronic transports,and magnetic properties are studied systematically.The temperature-dependent resistance curves of PSFO and LPSFO nanofibers are measured in a temperature range from 300 K to 10 K.With the temperature lowering,the resistance increases gradually and then decreases sharply due to the occurrence of ferromagnetic metal phase.The metal-insulator transition temperatures are about 110 K and 180 K for PSFO and LPSFO nanofibers,respectively.The electronic conduction behavior above the transition temperature can be described by one-dimensional Mott’s variable-range hopping(VRH)model.The hysteresis loops and the field-cooled(FC)and zero-field-cooled(ZFC)curves show that both PSFO nanofiber and LPSFO nanofiber exhibit ferromagnetism.Although the doping of La reduces the overall magnetization intensity of the material,it increases the ferromagnetic ratio of the system,which may improve the performance of LPSFO in solid oxide fuel cell.

NIR‑II‑Triggered Composite Nanofibers to Simultaneously Achieve Intracranial Hemostasis,Killing Superbug and Residual Cancer Cells in Brain Tumor Resection Surgery

Malignant glioblastoma(GBM)is prone to relapse due to the inevitable tumor cells residue by surgery.During the tumor resection surgery in brain,addressing bleeding and superbug infections is also full of challenges.Currently,no method or material in clinical craniotomy can simultaneously solve these three problems.Herein,Chitosan composite nanofibers embed-ded with CuSe nanoparticles were prepared by green electrospinning method,in which the CuSe nanoparticles have strong absorption in the second near-infrared(NIR-II)window.Immediately after removing the tumor in craniotomy,nanofibers were electrospun and deposited directly onto the resection site with high precision(>90%)to achieve rapid hemostasis(<8 s).Moreover,evidenced by the deeper penetration depth of NIR-II light(1064 nm)both in the scalp and skull than NIR-I light(808 nm),photothermal and photodynamic therapy induced by NIR-II exhibits efficient superbug-killing rate(>99%)and effectively induces cell apoptosis of residual tumor thereby to inhibit tumor recurrence.Only using the same material,a tril-ogy of intracranial hemostasis,killing superbug and residual cancer cells is simultaneously achieved.The short operation time reduces the risk of craniotomy.This electrospinning strategy could combine with craniotomy and minimally invasive surgery,which may provide novel perspectives in clinical operation besides craniotomy.

Weak UV‑Stimulated Synaptic Transistors Based on Precise Tuning of Gallium‑Doped Indium Zinc Oxide Nanofibers

In this work,a light-stimulated artificial synaptic transistor based on one-dimensional nanofibers of gallium-doped indium zinc oxides(IGZO)is demonstrated.The introduction of gallium into the nanofiber lattice can effectively alter the morphology and crystallinity,leading to a wider regulatory range of synaptic plasticity.The fabricated IGZO synaptic transistor with the optimal gallium concentration and low surface defects exhibits a superior photoresponsivity of 4300 A・W^(−1)and excellent photosensitivity,which can detect light signals as weak as 0.03 mW・cm^(−2).In particular,the paired-pulse facilitation index reaches up to 252%with over 2 h of enhanced memory retention exhibiting the long-term potentiation.Furthermore,the simulated image contrast and image recognition accuracy based on the newly designed IGZO synaptic transistors are successfully enhanced.These remarkable behaviors of light-stimulated synapses utilizing low-cost electrospun nanofibers have potential for ultraweak light applications in future artificial systems.

A non-surgical suturing strategy for rapid cardiac hemostasis

As the central organ of the human body,once the heart is damaged,it will cause devastating damage to the circulation system of the whole body,often leading to rapid death.Currently,the only treatment option to stop bleeding in penetrating cardiac injuries is surgical suturing,which is extremely complex and risky.In addition,it is difficult to implement this kind of treatment in battlefields with poor medical conditions.Therefore,there is an urgent need to develop an effective cardiac hemostasis strategy.In this work,we propose a two-step hemostasis strategy that can effectively stop bleeding for penetrating heart injuries.That is,cardiac hemostatic plug(CHP)is made from the nanocomposite(polylactic acid/gelatin/absorbable hemostatic particles,PLA/GEL/AHP)with high biosafety,excellent hemostatic performance,and degradability which is used to block cardiac bleeding,and then wound surface is sealed by in-situ electrospun medical glue fibers(N-octyl-2-cyanoacrylate,interfacial toughness:221±23 J·m−2),thus completing cardiac hemostasis(porcine heart with 1 cm diameter penetrating wound).The hemostasis process is simple and quick(<2 min).In addition,it is worth mentioning that we have also proposed a new composite method based on solution blow spinning that is suitable for doping various functional particles,and the PLA/GEL/AHP composite nanofiber membrane prepared by this method is also a promising hemostatic material.

用于低功率神经形态晶体管的金属氧化物半导体纳米纤维中阳离子比例的合理调整

宽带隙金属氧化物半导体(MOS)纳米纤维神经形态晶体管(NFNTs)可以潜在地用于构建低功耗的仿生人工电路.但文献中对于NFNTs所采用MOS的阳离子配比并没有给出详细的原因.在本研究中,我们首次系统地研究了用低成本静电纺丝技术结合纳米纤维转移工艺制备的氧化铟锌(InZnO)基NFNTs的阳离子比例.基于双阳离子InZnO纳米纤维的电驱动NFNTs可以大大简化实验过程.在In_(x)Zn_(1−x)O的阳离子比(x=0.6,0.7,0.8,0.9)中,我们发现基于In_(0.7)Zn_(0.3)O的NFNTs表现出最低的兴奋性突触后电流,可以为低功耗操作和突触功能模拟提供电效益.MOS纳米纤维成分的合理调整可以为高性能低功耗NFNTs提供新的思路.