annealing

退火
  • 文章类型: Journal Article
    在这项研究中,比较研究干热处理(DHT)和退火(ANN)对多结构的影响,研究了黑青麦(BHB)淀粉的理化性质和体外消化率。结果表明,DHT和ANN均不影响BHB淀粉的“A”型结晶模式和FT-IR光谱,但是改变了形态,提高吸水能力和降低粘度。与天然淀粉相比,DHT和ANN修饰的样品在直链淀粉含量方面具有完全相反的变化趋势,颜色特征,吸油能力,糊化参数和糊化温度。这些变化与DHT改性淀粉的处理温度和时间呈正相关,而这取决于ANN改性淀粉的治疗持续时间。DHT后淀粉中的总体外水解速率和快速消化淀粉含量显着提高,而缓慢消化的淀粉和RS水平下降。然而,随着处理时间的延长,ANN显著提高了水解稳定性,尤其是RS含量增加和RDS水平降低。因此,这项研究确定DHT和ANN是改变BHB淀粉性质的有效方法,更重要的是,它们通过不同的机制产生了不同的影响,这将提醒用户根据不同的应用目的选择合适的方法进行物理淀粉改性。
    In this study, comparative investigation on the effect of dry heating treatment (DHT) and annealing (ANN) on multi-structure, physicochemical properties and in vitro digestibility of black highland barley (BHB) starch was done. Results revealed that both DHT and ANN did not affect the \"A\"-type crystalline pattern and FT-IR spectroscopy of BHB starch, but changed the morphology, raised water absorption capacity and lowered viscosities. Compared to native starch, DHT- and ANN-modified samples had totally opposite alteration trends in amylose content, color characteristics, oil absorption capacity, gelatinization parameters and pasting temperature. These changes were positively related to treatment temperature and time for DHT-modified starches, while which were dependant on treatment duration for ANN-modified starches. Total in vitro hydrolysis rate and rapidly digestive starch content in starch markedly raised after DHT, whereas slowly digestive starch and RS levels decreased. Nevertheless, ANN significantly improved the hydrolyzation stability with treatment time prolonging, especially increased RS content and lowered RDS level. Therefore, this study identified both DHT and ANN were effective methods to alter the properties of BHB starch, and more importantly, they had distinguishing influence by different mechanisms, which would remind user to select appropriate means for physical starch modification based on different application purposes.
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  • 文章类型: Journal Article
    磁控溅射热电薄膜具有再现性和可扩展性的潜力。然而,溅射过程中的晶格失配会导致外延层中缺陷增加,这对提高它们的热电性能提出了重大挑战。在这项工作中,使用高温溅射和后退火制备平均晶粒尺寸为≈110nm的纳米晶体n型Bi2Te3薄膜。在这里,证明高温处理会加剧Te的蒸发,产生Te空位和类似电子的效应.退火提高结晶度,增加晶粒尺寸,并减少缺陷,这显著增加了载流子迁移率。此外,预沉积的Ti添加剂在高温下离子化并部分扩散到Bi2Te3中,导致增加载流子浓度的Ti掺杂效应。总的来说,1µm厚的n型Bi2Te3薄膜的室温电阻率低至3.56×10-6Ω.m。值得注意的是,5μm厚的Bi2Te3薄膜在室温下实现了6.66mWmK-2的创纪录功率因数,这是迄今为止使用磁控溅射的n型Bi2Te3薄膜的最高值。这项工作证明了用于室温TE应用的大规模高质量Bi2Te3基薄膜和器件的潜力。
    Magnetron-sputtered thermoelectric thin films have the potential for reproducibility and scalability. However, lattice mismatch during sputtering can lead to increased defects in the epitaxial layer, which poses a significant challenge to improving their thermoelectric performance. In this work, nanocrystalline n-type Bi2Te3 thin films with an average grain size of ≈110 nm are prepared using high-temperature sputtering and post-annealing. Herein, it is demonstrated that high-temperature treatment exacerbates Te evaporation, creating Te vacancies and electron-like effects. Annealing improves crystallinity, increases grain size, and reduces defects, which significantly increases carrier mobility. Furthermore, the pre-deposited Ti additives are ionized at high temperatures and partially diffused into Bi2Te3, resulting in a Ti doping effect that increases the carrier concentration. Overall, the 1 µm thick n-type Bi2Te3 thin film exhibits a room temperature resistivity as low as 3.56 × 10-6 Ω∙m. Notably, a 5 µm thick Bi2Te3 thin film achieves a record power factor of 6.66 mW mK-2 at room temperature, which is the highest value reported to date for n-type Bi2Te3 thin films using magnetron sputtering. This work demonstrates the potential for large-scale of high-quality Bi2Te3-based thin films and devices for room-temperature TE applications.
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  • 文章类型: Journal Article
    目的:本文研究了冻干微丸中材料厚度对提高封装菌储存稳定性的关键作用。使用扫描电子显微镜(SEM)和X射线显微断层扫描(μCT)对从不同退火持续时间获得的不同厚度的冷冻干燥材料进行定量。然后将材料厚度与封装的细胞的储存稳定性相关联。
    方法:包含蔗糖,麦芽糊精,益生菌细胞在液氮中淬灭形成颗粒。粒料在经历冷冻干燥之前经历不同的退火持续时间。使用SEM和μCT定量材料厚度。通过测量CFU计数来评估富氧和贫氧环境中的储存稳定性,并将其与颗粒结构相关联。
    结果:不同的退火方案产生一系列材料厚度,更广泛的退火导致较厚的材料。储存稳定性与材料厚度呈正相关,表明使用较厚的材料改善了稳定性。未退火的颗粒表现出结构不规则性和不一致的储存稳定性,突出了在冷冻干燥过程中避免退火的不切实际。
    结论:大量退火不仅增强了益生菌产品的储存稳定性,而且对冷冻干燥过程提供了更大的控制,确保均匀和可重复的产品。这项研究强调了冻干颗粒中材料厚度对优化益生菌制剂储存稳定性的重要性。并强调退火作为冷冻干燥淬火颗粒的关键步骤的必要性,以实现所需的结构和稳定性结果。
    OBJECTIVE: This paper investigates the critical role of material thickness in freeze-dried pellets for enhancing the storage stability of encapsulated bacteria. Freeze dried material of varying thicknesses obtained from different annealing durations is quantified using Scanning Electron Microscopy (SEM) and X-ray microtomography (μCT), the material thickness is then correlated to the storage stability of the encapsulated cells.
    METHODS: A formulation comprising of sucrose, maltodextrin, and probiotic cells is quenched in liquid nitrogen to form pellets. The pellets undergo different durations of annealing before undergoing freeze-drying. The material thickness is quantified using SEM and μCT. Storage stability in both oxygen-rich and oxygen-poor environments is evaluated by measuring CFU counts and correlated with the pellet structure.
    RESULTS: The varying annealing protocols produce a range of material thicknesses, with more extensive annealing resulting in thicker materials. Storage stability exhibits a positive correlation with material thickness, indicating improved stability with thicker materials. Non-annealed pellets exhibit structural irregularities and inconsistent storage stability, highlighting the impracticality of avoiding annealing in the freeze-drying process.
    CONCLUSIONS: Extensive annealing not only enhances the storage stability of probiotic products but also provides greater control over the freeze-drying process, ensuring homogeneous and reproducible products. This study underscores the importance of material thickness in freeze-dried pellets for optimizing storage stability for probiotic formulations, and emphasize the necessity of annealing as a critical step in freeze-drying quenched pellets to achieve desired structural and stability outcomes.
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  • 文章类型: Journal Article
    在本文中,在AISI304奥氏体不锈钢上通过感应加热和充填渗铬制备了Cr涂层。然后,引入冷轧变形和退火处理,以细化由包渗铬引起的粗大基体晶粒,提高304奥氏体不锈钢的综合性能。相组成,元素分布,并仔细表征了涂层的微观结构。显微硬度,耐磨性,并对涂层的耐腐蚀性能进行了测试。结果表明,厚度为100μm的Cr涂层主要由一种(Cr,Fe)23C6,(Cr,Fe)7C3和α-Fe-Cr固溶体。经过冷轧变形和随后的退火处理,晶粒显著细化,Cr涂层分为两层,由碳铬化合物组成,如Cr23C6、Cr7C3、Cr2C、表面层中的Cr3C2和亚表面层中的Fe-Cr固溶体。冷轧变形和退火处理显著提高了涂层试样的显微硬度和耐磨性,耐腐蚀性也优于未涂覆样品。
    In this paper, a Cr coating was prepared by induction heating and pack-cementation chromizing on AISI 304 austenitic stainless steel. Then, the cold-rolling deformation and annealing treatment were introduced to refine the coarse matrix grains caused by pack-chromizing and improve the overall performance of 304 austenitic stainless steel. The phase composition, element distribution, and microstructure of the coating were carefully characterized. The microhardness, wear resistance, and corrosion resistance of the coating were tested. The results show that the Cr coating with a thickness of 100 μm is mainly composed of a (Cr,Fe)23C6, (Cr,Fe)7C3, and α-Fe-Cr solid solution. After the cold-rolling deformation and subsequent annealing treatment, the grains are significantly refined and the Cr coating is divided into two layers, consisting of carbon-chromium compounds such as Cr23C6, Cr7C3, Cr2C, and Cr3C2 in the surface layer and a Fe-Cr solid solution in the subsurface layer. The cold-rolling deformation and annealing treatment significantly improved the microhardness and wear resistance of the coated sample, and the corrosion resistance was also better than that of the uncoated sample.
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  • 文章类型: Journal Article
    在700至1000°C的温度范围内研究了铁基316L不锈钢的氧化行为。通过选择性激光熔化生产板状的试样。制作后,将样品喷砂,然后在空气中退火不同的时间(0.5、2、8、32小时)。在温度和时间的影响下,不锈钢倾向于形成氧化层。扫描电子显微镜,能量色散分析,和X射线衍射用于分析该层的组成。值得注意的是,主要由(Fe-Cr)组成的薄氧化物层由于温度的影响而形成在表面上。此外,随着温度的升高(高达1000°C),主要合金元素的氧化物,具体地,Mn2(Fe-Cr)O4与Fe-Cr氧化物一起出现。此外,对样品进行转换X射线(CXMS)和转换电子(CEMS)穆斯堡尔谱。基于表面金属氧化物的厚度,CXMS显示出具有降低的穆斯堡尔效应的单重态。CEMS显示在表面层(0.3μm)中存在Fe3+。此外,在较高的温度水平下发生了一个有趣的现象,这是由于表面金属氧化物层厚度不均匀以及穆斯堡尔辐射朝向电子探测器的切线方向。
    The oxidation behaviour of iron-based 316L stainless steel was investigated in the temperature range of 700 to 1000 °C. The test specimens in the shape of plates were produced by selective laser melting. After fabrication, the samples were sandblasted and then annealed in air for different periods of time (0.5, 2, 8, 32 h). Under the influence of temperature and time, stainless steels tend to form an oxide layer. Scanning electron microscopy, energy dispersive analysis, and X-ray diffraction were employed to analyse the composition of this layer. Notably, a thin oxide layer primarily composed of (Fe-Cr) formed on the surface due to temperature effects. In addition, with increasing temperature (up to 1000 °C), the oxide of the main alloying elements, specifically Mn2(Fe-Cr)O4, appeared alongside the Fe-Cr oxide. Furthermore, the samples were subjected to conversion X-ray (CXMS) and conversion electron (CEMS) Mössbauer spectroscopy. CXMS revealed a singlet with a decreasing Mössbauer effect based on the surface metal oxide thickness. CEMS revealed the presence of Fe3+ in the surface layer (0.3 µm). Moreover, an interesting phenomenon occurred at higher temperature levels due to the inhomogeneously thick surface metal oxide layer and the tangential direction of the Mössbauer radiation towards the electron detector.
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  • 文章类型: Journal Article
    热处理对于优化钛合金的强度性能和提高其韧性具有重要意义。在这项研究中,我们研究了三种热处理方法(β-退火,双重退火,以及固溶和时效处理)对Ti555211钛合金的力学性能和断口形貌的影响。结果表明,经过β-退火处理,合金保持高强度,虽然几乎没有延展性,没有屈服强度。二次退火后的合金具有较高的伸长率(~54%)和较低的强度。固溶和时效热处理后,该合金能够同时保持高强度和一定程度的延展性。最佳热处理工艺为固溶处理820℃/2h,时效处理560℃/12h,这导致1404MPa的最大拉伸强度和11%的伸长率。
    Heat treatment is important for optimizing the strength performance and improving the toughness of titanium alloys. In this study, we investigated the impact of three heat treatment methods (β-annealing, double annealing, and solid-solution and aging treatment) on the mechanical properties and fracture morphology of Ti555211 titanium alloy. The results show that after β-annealing treatment, the alloy retains a high strength, while showing almost no ductility, and no yield strength. The alloy after double annealing has a high elongation rate (~54%) and lower strength. After solid-solution and aging heat treatment, the alloy was able to retain both high strength and a certain degree of ductility. The optimal heat-treatment process is solid-solution treatment at 820 °C/2 h and aging at 560 °C/12 h, which results in a maximum tensile strength of 1404 MPa and an elongation rate of 11%.
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  • 文章类型: Journal Article
    迄今为止,精心开发了无数的神经微电极,但是现有文献的重点主要围绕制造方法,而不是深入研究修复过程或回收电极的策略,这些电极由于材料失效而表现出性能下降。本研究旨在阐明导致神经微电极性能下降的潜在因素。此外,它介绍了一个全面的,成本有效的协议,用于修复和重新利用受材料故障影响的电极,为广泛的电极类型量身定制。通过在单位点钨微电极上的实验验证,证实了所提出的修复方案的有效性。神经信号记录的结果明确地证明了大量电极的成功恢复,强调协议的有效性。
    To date, a myriad of neural microelectrodes has been meticulously developed, but the focus of existing literature predominantly revolves around fabrication methodologies rather than delving into the reconditioning processes or strategies for salvaging electrodes exhibiting diminished performance due to material failure. This study aims to elucidate the underlying factors contributing to the degradation in performance of neural microelectrodes. Additionally, it introduces a comprehensive, cost-effective protocol for the reconditioning and repurposing of electrodes afflicted by material failure, tailored for a broad spectrum of electrode types. The efficacy of the proposed reconditioning protocol is substantiated through experimental validation on single-site tungsten microelectrodes. The results of neural signal recording unequivocally demonstrate the successful restoration of a substantial number of electrodes, underscoring the protocol\'s effectiveness.
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  • 文章类型: Journal Article
    具有快速响应的光电突触,低功耗,和记忆功能在未来的人工智能技术中具有巨大的潜力。在这里,提出了一种在不同温度下在氧气环境中退火的策略,以改善富含受体的ZnO(A-ZnO)微管的光电突触行为。生长和退火的A-ZnO微管的基本突触功能,包括兴奋性突触后电流(EPSC),短期记忆(STM)到长期记忆(LTM)的转换,和配对脉冲促进(PPF),成功模拟。结果表明,与其他退火的A-ZnO微管相比,600°C的退火温度可产生较高的品质因数。在600°C退火的A-ZnO微管中实现了取决于光脉冲持续时间和能量密度的4倍和20倍增强,分别。此外,该设备的PPF指数高达238%,实现了四个“学习遗忘”过程周期,证明了其光学信息存储的能力。自由激子(FX)和供体-受体对(DAP)浓度显着影响A-ZnO微管的持久光电导(PPC)行为。因此,LTM响应可以通过调整数字来控制,权力,和光学刺激的间隔时间。这项工作概述了通过缺陷控制来改善EPSC响应的策略,代表了光电突触装置领域应用的一步。
    Optoelectronic synapses with fast response, low power consumption, and memory function hold great potential in the future of artificial intelligence technologies. Herein, a strategy of annealing in oxygen ambient at different temperatures is presented to improve the optoelectronic synaptic behaviors of acceptor-rich ZnO (A-ZnO) microtubes. The basic synaptic functions of as-grown and annealed A-ZnO microtubes including excitatory postsynaptic current (EPSC), short-term memory (STM) to long-term memory (LTM) conversion, and paired-pulse facilitation (PPF), were successfully emulated. The results show that the annealing temperature of 600 °C yields high figures of merit compared to other annealed A-ZnO microtubes. The 4-fold and 20-fold enhancement dependent on the light pulse duration time and energy density have been achieved in the 600 °C annealed A-ZnO microtube, respectively. Furthermore, the device exhibited a PPF index of up to 238% and achieved four cycles of \"learning-forgetting\" process, proving its capability for optical information storage. The free exciton (FX) and donor-acceptor pair (DAP) concentrations significantly influenced the persistent photoconductivity (PPC) behavior of A-ZnO microtubes. Therefore, the LTM response can be controlled by the adjustment of numbers, powers, and interval time of the optical stimulation. This work outlines a strategy to improve the EPSC response through defect control, representing a step towards applications in the field of optoelectronic synaptic device.
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  • 文章类型: Journal Article
    回收的钠钙玻璃粉是一种可持续的材料,通常也被认为是水泥基复合材料中的填料。通过X射线光电子能谱(XPS)和光谱学分析了由于处理而引起的玻璃颗粒表面性质的变化。我们已经发现,在玻璃颗粒的表面上存在相对较高的碳污染水平(约30at。%),因此,对等离子体技术和热退火进行了表面清洁测试。室温等离子体处理不足以从回收的玻璃颗粒的表面去除碳污染物。相反,回收的钠钙玻璃颗粒的室温等离子体处理通过增加强度和加速光致发光的衰减而导致其室温光致发光(PL)的显着增强。室温等离子体处理后增强的蓝色PL归因于玻璃表面上存在碳污染以及相关的电荷表面和界面缺陷和界面状态。因此,我们提出了在UVLED下的蓝色光致发光作为一种快速且廉价的方法来指示玻璃颗粒表面上的碳污染。
    Recycled soda-lime glass powder is a sustainable material that is also often considered a filler in cement-based composites. The changes in the surface properties of the glass particles due to the treatments were analyzed by X-ray photoelectron spectroscopy (XPS) and optical spectroscopy. We have found that there is a relatively high level of carbon contamination on the surface of the glass particles (around 30 at.%), so plasma technology and thermal annealing were tested for surface cleaning. Room temperature plasma treatment was not sufficient to remove the carbon contamination from the surface of the recycled glass particles. Instead, the room temperature plasma treatment of recycled soda-lime glass particles leads to a significant enhancement in their room temperature photoluminescence (PL) by increasing the intensity and accelerating the decay of the photoluminescence. The enhanced blue PL after room-temperature plasma treatment was attributed to the presence of carbon contamination on the glass surface and associated charge surface and interfacial defects and interfacial states. Therefore, we propose blue photoluminescence under UV LED as a fast and inexpensive method to indicate carbon contamination on the surface of glass particles.
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  • 文章类型: Journal Article
    过渡边缘传感器(TES)微热计是先进的低温探测器,使用超导薄膜进行粒子或光子检测。我们正在为TES探测器建立一条新的生产线,以作为低温反符合(即,否决)设备。这些检测器由在高真空条件下通过电子束蒸发在单晶硅衬底上沉积的钛(Ti)和金(Au)薄膜的超导双层制成。在这项工作中,我们报告了这种传感器的发展,旨在实现稳定的传感性能,尽管老化的影响。为此,使用微加工技术制造具有不同几何形状和厚度的图案化和非图案化Ti/Au双层样品。为了表征探测器,我们介绍并讨论随着时间的推移重复电阻-温度(R-T)测量的初始结果,在不同的样本上进行,从而扩大现有的文献数据。此外,我们提出了一个讨论的传感器的退化随着时间的推移,由于老化效应和测试一个潜在的补救措施的基础上,一个简单的退火程序。在我们看来,这项工作为我们新的TES探测器生产线奠定了基础。
    Transition-edge sensor (TES) microcalorimeters are advanced cryogenic detectors that use a superconducting film for particle or photon detection. We are establishing a new production line for TES detectors to serve as cryogenic anticoincidence (i.e., veto) devices. These detectors are made with a superconducting bilayer of titanium (Ti) and gold (Au) thin films deposited via electron beam evaporation in a high vacuum condition on a monocrystalline silicon substrate. In this work, we report on the development of such sensors, aiming to achieve stable sensing performance despite the effects of aging. For this purpose, patterned and non-patterned Ti/Au bilayer samples with varying geometries and thicknesses were fabricated using microfabrication technology. To characterize the detectors, we present and discuss initial results from repeated resistance-temperature (R-T) measurements over time, conducted on different samples, thereby augmenting existing literature data. Additionally, we present a discussion of the sensor\'s degradation over time due to aging effects and test a potential remedy based on an easy annealing procedure. In our opinion, this work establishes the groundwork for our new TES detector production line.
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