Charge trapping effect at the interface of ferroelectric/interlayer in the ferroelectric field effect transistor gate stack

We study the charge trapping phenomenon that restricts the endurance of n-type ferroelectric field-effect transistors(FeFETs)with metal/ferroelectric/interlayer/Si(MFIS)gate stack structure.In order to explore the physical mechanism of the endurance failure caused by the charge trapping effect,we first establish a model to simulate the electron trapping behavior in n-type Si FeFET.The model is based on the quantum mechanical electron tunneling theory.And then,we use the pulsed I_d-V_g method to measure the threshold voltage shift between the rising edges and falling edges of the FeFET.Our model fits the experimental data well.By fitting the model with the experimental data,we get the following conclusions.(i)During the positive operation pulse,electrons in the Si substrate are mainly trapped at the interface between the ferroelectric(FE)layer and interlayer(IL)of the FeFET gate stack by inelastic trap-assisted tunneling.(ii)Based on our model,we can get the number of electrons trapped into the gate stack during the positive operation pulse.(iii)The model can be used to evaluate trap parameters,which will help us to further understand the fatigue mechanism of FeFET.

Localized electrodeposition micro additive manufacturing of pure copper microstructures

The fabrication of pure copper microstructures with submicron resolution has found a host of applications,such as 5G communications and highly sensitive detection.The tiny and complex features of these structures can enhance device performance during high-frequency operation.However,manufacturing pure copper microstructures remain challenging.In this paper,we present localized electrochemical deposition micro additive manufacturing(LECD-μAM).This method combines localized electrochemical deposition(LECD)and closed-loop control of atomic force servo technology,which can effectively print helical springs and hollow tubes.We further demonstrate an overall model based on pulsed microfluidics from a hollow cantilever LECD process and closed-loop control of an atomic force servo.The printing state of the micro-helical springs can be assessed by simultaneously detecting the Z-axis displacement and the deflection of the atomic force probe cantilever.The results showed that it took 361 s to print a helical spring with a wire length of 320.11μm at a deposition rate of 0.887μm s^(-1),which can be changed on the fly by simply tuning the extrusion pressure and the applied voltage.Moreover,the in situ nanoindenter was used to measure the compressive mechanical properties of the helical spring.The shear modulus of the helical spring material was about 60.8 GPa,much higher than that of bulk copper(~44.2 GPa).Additionally,the microscopic morphology and chemical composition of the spring were characterized.These results delineate a new way of fabricating terahertz transmitter components and micro-helical antennas with LECD-μAM technology.

Experimental and mechanistic study on chemical looping combustion of caking coal

Under high-temperature batch fluidized bed conditions and by employing juye coal as the raw material,the present study determined the effects of the bed material,temperature,OC/C ratio,steam flow and oxygen carrier cycle on the chemical looping combustion of coal.In addition,the variations taking place in the surface functional groups of coal under different reaction times were investigated,and the variations achieved by the gas released under the pyrolysis and combustion of Juye coal were analyzed.As revealed from the results,the carbon conversion ratio and rate were elevated significantly,and the volume fraction of the outlet CO_(2)remained more than 92%under the oxygen carriers.The optimized reaction conditions to achieve the chemical looping combustion of Juye coal consisted of a temperature of 900℃,an OC/C ratio of 2,as well as a steam flow rate of 0.5 g·min^(-1).When the coal was undergoing the chemical looping combustion,volatiles primarily originated from the pyrolysis of aliphatic-CH_(3)and-CH_(2),and CO and H_(2)were largely generated from the gasification of aromatic carbon.In the CLC process,H_(2)O and CO_(2)began to separate out at 270℃,CH4 and tar began to precipitate at 370℃,and the amount of CO_(2)was continuously elevated with the rise of the temperature.

On the Financial Management Strategy under the Background of Corporate Sustainable Development

Sustainable development is the basis of survival. The SMEs as an important part of our national economy, plays the role of increasing national income, expanding employment, stabilizing social situation. Under the new situation, it needs to change the status quo of financial management, financial management to achieve sustainable development of SMEs. This paper is combined with the financial management of the significance of sustainable development as well as financial management problems in the SME financial management strategy.

烟煤化学链反应特性及机理分析

在固定床反应器中添加铁基载氧体Fe4Al6和铜基载氧体Cu4Al6,进行巨野(JY)烟煤化学链燃烧实验,通过气相色谱(GC)、红外光谱(FT-IR)等分析了JY煤化学链反应特性及表面官能团演变规律。结果表明,相对于Al2O3,Fe4Al6或Cu4Al6为床料时,JY煤中CO2含量分别提高了52.25%和59.16%,最大碳转化速率分别提高了8.93%和30.36%,Cu4Al6反应效果更好。添加Cu4Al6后,JY煤表面官能团演变进程加快,Cu4Al6对脂肪烃结构、芳香碳骨架和芳香族CH的转化均有明显促进作用。煤中脂肪烃-CH3和-CH2稳定性低、反应速率快,是化学链燃烧初期气相产物主要来源;芳香碳骨架和芳香族-CH稳定性高、反应活性低,反应速率较缓慢,是化学链燃烧中后期气相产物主要来源。

Temperature‑Regulating Phase Change Fiber Scaffold Toward Mild Photothermal–Chemotherapy

Photothermal therapy(PTT)is a treatment that increases the temperature of tumors to 42–48℃,or even higher for tumor ablation.PTT has sparked a lot of attention due to its ability to induce apoptosis or increase sensitivity to chemotherapy.Excessive heat not only kills the tumor cells,but also damages the surrounding healthy tissue,reducing therapeutic accuracy and increasing the possible side effects.Herein,a phase change fiber(PCF)scaffold serving as a thermal trigger in mild photothermal–chemo tumor therapy is developed to regulate temperature and control drug release.These prepared PCFs,comprised of hollow carbon fibers(HCFs)loaded with lauric acid as a phase change material(PCM),can effectively store and release any excess heat generated by irradiating with a near-infrared(NIR)laser through the reversible solid–liquid transition process of the PCM.With this feature,the optimal PTT temperature of implanted PCF-based composite scaffolds was identified for tumor therapy with minimal normal tissue damage.In addition,controlled release of chemotherapeutic drugs and heat shock protein(HSP)inhibitors from the PCF-based composite scaffolds have been shown to improve the efficacy of mild PTT.The developed PCF-based scaffold sheds light on the development of a new generation of therapeutic scaffolds for thermal therapy.

Graphene oxide and mineralized collagen-functionalized dental implant abutment with effective soft tissue seal and romotely repeatable photodisinfection

Grasping the boundary of antibacterial function may be better for the sealing of soft tissue around dental implant abutment.Inspired by‘overdone is worse than undone’,we prepared a sandwich-structured dental implant coating on the percutaneous part using graphene oxide(GO)wrapped under mineralized collagen.Our unique coating structure ensured the high photothermal conversion capability and good photothermal stability of GO.The prepared coating not only achieved suitable inhibition on colonizing bacteria growth of Streptococcus sanguinis,Fusobacterium nucleatum and Porphyromonas gingivalis but also disrupted the wall/membrane permeability of free bacteria.Further enhancements on the antibacterial property were generally observed through the additional incorporation of dimethylaminododecyl methacrylate.Additionally,the coating with sandwich structure significantly enhanced the adhesion,cytoskeleton organization and proliferation of human gingival fibroblasts,which was effective to improve soft tissue sealing.Furthermore,cell viability was preserved when cells and bacteria were cultivated in the same environment by a coculture assay.This was attributed to the sandwich structure and mineralized collagen as the outmost layer,which would protect tissue cells from photothermal therapy and GO,as well as accelerate the recovery of cell activity.Overall,the coating design would provide a useful alternative method for dental implant abutment surface modification and functionalization.

肺原发性肌周皮细胞瘤1例

本文报道肺原发性肌周皮细胞瘤1例。患者男,29岁,7年前因体检发现肺部肿物,未接受系统治疗。近期CT复查发现肿物较前增大而来本院就诊。患者无明显临床症状,胸部CT平扫示右肺下叶类圆形结节,密度均匀,边缘清晰。行右肺下叶楔形切除术,术后病理确诊为肌周皮细胞瘤。