uniformity

均匀度
  • 文章类型: English Abstract
    目的:本研究的目的是评估几种新型防辐射服的防护性能,并阐明质量控制问题。
    方法:使用X射线荧光分析法分析屏蔽元件的组成,并测量了透射X射线的能谱。此外,根据日本工业标准(JIS)从透射X射线剂量测量铅当量和均匀性。除了常规方法之外,通过透射每种辐射防护服的X射线图像来评价均匀性。
    结果:能谱显示铅的K吸收边缘,铋,锡,等。,在成分分析中检测到的。多层保护材料在高管电压下保持较高的屏蔽能力。此外,防辐射服的X射线图像显示密度和斑点不均匀,并且看到了不满足屏蔽能力要求的均匀性测量方法和点的差异。
    结论:当前的JIS不允许对铅当量和均匀性进行准确评估,所以X射线图像的视觉评估很重要。有必要为每个设施执行的质量控制建立标准化标准。
    OBJECTIVE: The purpose of this study was to evaluate the protective performance of several new radiation-protective clothing and to clarify issues of quality control.
    METHODS: The composition of the shielding elements was analyzed using X-ray fluorescence analysis, and the energy spectrum of transmitted X-rays was measured. Furthermore, the lead equivalent and uniformity were measured from the transmitted X-ray doses according to Japanese industrial standards (JIS). Uniformity was evaluated by transmitting X-ray images of each radiation protective clothing in addition to the conventional method.
    RESULTS: The energy spectrum showed K-absorption edges of lead, bismuth, tin, etc., which were detected in the composition analysis. The multi-layered protective material maintained higher shielding ability at high tube voltages. In addition, X-ray images of the radiation-protective clothing showed uneven density and dots, and the differences in uniformity measurement methods and points that didn\'t meet the required shielding capacity were seen.
    CONCLUSIONS: The current JIS does not allow accurate evaluation of the lead equivalent and uniformity, so visual evaluation of X-ray images is important. It is necessary to establish standardized standards for quality control performed by each facility.
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  • 文章类型: Journal Article
    背景:皮肤“黄度”是一个抽象和主观的术语,没有明确的测量协议。目的是分析中国女性对皮肤黄度的自我感知和相关参数,并确定与这些感知相关的客观临床测量。
    方法:在焦点小组讨论之后,定义了皮肤泛黄的标准,并通过志愿者的面部图像排名进行验证。对185名妇女进行了类型学研究。参与者被分组为黄色(颜色均匀性,亮度和透明度(CUBT)黄色刻度等级>3,色度b*值>16)和非黄色(CUBT黄色刻度等级<2,b*值<14)组。参与者自我评估他们的皮肤泛黄,透明度,皮肤均匀性,迟钝,辐射,油性,和纹理。对皮脂腺毛孔进行了专家评估,眼区色素沉着,色素性斑点和CUBT评分。使用角膜测量仪对皮肤进行仪器分析,粘度计,mexameter色度仪,年龄的读者。
    结果:黄色组的女性自我评价她们的皮肤明显暗淡,不那么均匀,且辐射小于非黄色组女性(P≤0.05)。在黄色皮肤的女性中观察到较高水平的眼部区域色素沉着和较低的面部皮肤均匀性和亮度(P<0.001)。CUBT专家分级显示较低的粉红色肤色,但是米色明显更高,黄色,黄皮肤组女性的橄榄色色素沉着(P≤0.05)。黑色素和b*值在皮肤发黄的女性中显著较高,而L值显著较低。
    结论:中国女性自我感知的皮肤发黄与色度测量值相关,以及眼部色素沉着和CUBT参数的专家评估。
    BACKGROUND: Skin \"yellowness\" is an abstract and subjective term, without a definitive measurement protocol. Objectives were to analyze Chinese women\'s self-perception of skin yellowness and associated parameters and identify objective clinical measurements that correlate with these perceptions.
    METHODS: Following focus group discussions, criteria for skin yellowness were defined, and validated by volunteer rankings of facial images. A typology study of 185 women was performed. Participants were grouped into yellow (Color Uniformity, Brightness and Transparency (CUBT) yellow scale grade > 3, chromameter b* value > 16) and non-yellow (CUBT yellow scale grade < 2, b* value < 14) groups. Participants self-evaluated their skin on yellowness, transparency, skin uniformity, dullness, radiance, oiliness, and texture. Expert assessments were performed to grade sebaceous pores, ocular area pigmentation, pigmentary spots and CUBT scores. Instrumental analysis of the skin was employed using corneometer, sebumeter, mexameter chromameter, and AGE reader.
    RESULTS: Women in the yellow group self-evaluated their skin as significantly duller, less uniform, and less radiant than women in the non-yellow group (P ≤ 0.05). Higher levels of ocular area pigmentation and lower facial skin uniformity and brightness (P < 0.001) were observed in women with yellow skin. CUBT expert grading showed lower pink skin color, but significantly higher beige, yellow, and olive pigmentation (P ≤ 0.05) in women in the yellow skin group. Melanin and b* values were significantly higher in women with yellow skin while L value was significantly lower.
    CONCLUSIONS: Self-perceived skin yellowness in Chinese women correlates to chromameter and mexameter measurements, as well as expert evaluation of ocular pigmentation and CUBT parameters.
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  • 文章类型: Journal Article
    风冷质子交换膜燃料电池(AC-PEMFC)在水和热管理方面的当前局限性仍然是其商业化的主要障碍。构建了90cm2全尺寸AC-PEMFC多物理场耦合数值模型;进行了等温和非等温计算,以探索单变量和多变量对电池性能的影响,分别。等温结果表明,较低的温度有利于增加MEA的湿度,在较低的化学计量比和较低的温度下的分布均匀性更好。电流密度分布与温度的相关性,含水量,和浓度分布表明AC-PEMFCs的性能受多种因素的影响。值得注意的是,在大电流运行下,产生的大量热量可能导致局部温度高和性能下降,特别是在较干燥的MEA下通道区域。较高的化学计量比可以增强散热,提高电流密度的均匀性,并增加功率密度。最佳的燃料电池性能是在化学计量比为300的情况下实现的,平衡了多种因素的混合影响。
    The current limitations of air-cooled proton exchange membrane fuel cells (AC-PEMFCs) in water and heat management remain a major obstacle to their commercialization. A 90 cm2 full-size AC-PEMFC multi-physical field-coupled numerical model was constructed; isothermal and non-isothermal calculations were performed to explore the effects of univariate and multivariate variables on cell performance, respectively. The isothermal results indicate that lower temperature is beneficial to increase the humidity of MEA, and distribution uniformity at lower stoichiometric ratios and lower temperatures is better. The correlation between current density distribution and temperature, water content, and concentration distribution shows that the performance of AC-PEMFCs is influenced by multiple factors. Notably, under high current operation, the large heat generation may lead to high local temperature and performance decline, especially in the under-channel region with drier MEA. The higher stoichiometric ratio can enhance heat dissipation, improve the uniformity of current density, and increase power density. Optimal fuel cell performance is achieved with a stoichiometric ratio of 300, balancing the mixed influence of multiple factors.
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  • 文章类型: Journal Article
    真空闪蒸法在钙钛矿薄膜制备中获得了普遍认可,为钙钛矿太阳能电池的产业化奠定基础。然而,二甲基亚砜的低挥发性及其与甲脒基钙钛矿的弱相互作用显著阻碍了电池组件的制备和光伏性能的进一步提高。在这项研究中,我们描述了一种有效且可重复的大规模制备方法,高度均匀的甲脒三碘化铅(FAPbI3)钙钛矿薄膜。这是通过加速真空闪蒸速率和利用复杂的协同作用来实现的。具体来说,我们设计了双泵系统来加速真空系统的减压速度,并比较了在不同减压速度下形成的钙钛矿薄膜的质量。Further,为了克服DMSO带来的限制,我们用N-甲基吡咯烷酮作为配体溶剂,产生稳定的中间复杂相。退火后,它可以转化为均匀且无针孔的FAPbI3膜。由于这些薄膜的质量优越,大面积钙钛矿太阳能组件实现了22.7%的功率转换效率,有效面积为21.4cm2。此外,它获得了22.1%的官方认证效率,孔径面积为22cm2,并表现出长期稳定性。
    The vacuum flash solution method has gained widespread recognition in the preparation of perovskite thin films, laying the foundation for the industrialization of perovskite solar cells. However, the low volatility of dimethyl sulfoxide and its weak interaction with formamidine-based perovskites significantly hinder the preparation of cell modules and the further improvement of photovoltaic performance. In this study, we describe an efficient and reproducible method for preparing large-scale, highly uniform formamidinium lead triiodide (FAPbI3) perovskite films. This is achieved by accelerating the vacuum flash rate and leveraging the complex synergism. Specifically, we designed a dual pump system to accelerate the depressurization rate of the vacuum system and compared the quality of perovskite film formed at different depressurization rates. Further, to overcome the limitations posed by DMSO, we substituted N-methylpyrrolidone as the ligand solvent, creating a stable intermediate complex phase. After annealing, it can be transformed into a uniform and pinhole-free FAPbI3 film. Due to the superior quality of these films, the large area perovskite solar module achieved a power conversion efficiency of 22.7% with an active area of 21.4 cm2. Additionally, it obtained an official certified efficiency of 22.1% with an aperture area of 22 cm2, and it demonstrated long-term stability.
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  • 文章类型: Journal Article
    在这项研究中,我们的目标是量化涂层的均匀性,并将荧光强度与药物负载相关联,该药物涂层的血管成形术球囊(DCB)涂覆有5,10,15或20层的聚(乳酸-羟基乙酸共聚物)纳米颗粒(NP)包裹有槲皮素.均匀性是从用样品特定参数获得的显微荧光图像的直方图和水平线轮廓量化的。并对涂层中的裂纹进行测量和计数。用全局参数获得的图像的荧光与通过重量/HPLC分析测量的槲皮素负载相关。DCB上的更多层可能与较不均匀的涂层相关联,如直方图标准偏差的差异所示。每个样品的线轮廓与平均值的百分比偏差<20%。所有气球上都有裂缝,但它们的长度在样品之间没有显着差异。5层DCB的裂缝最少,而15层DCB的裂缝最多。在荧光强度和载药量之间鉴定出强的正相关(R=0.896)。层数和涂层均匀性之间似乎存在关系,但需要进一步调查才能确认。荧光强度似乎有力地预测了载药量,证明荧光成像可能是药物释放研究的可行替代方法。
    In this study, we aim to quantify coating uniformity and correlate fluorescence intensity to drug loading for drug-coated angioplasty balloons (DCB) coated with 5, 10, 15, or 20 layers of poly(lactic-co-glycolic acid) nanoparticles (NPs) entrapped with quercetin. Uniformity was quantified from histograms and horizontal line profiles of microscopic fluorescent images acquired with sample specific parameters, and cracks in the coating were measured and counted. The fluorescence of images acquired with global parameters was correlated with quercetin loading measured via gravimetric/HPLC analysis. More layers on DCBs may be associated with less uniform coatings, as indicated by differences in histogram standard deviations. The line profile percent deviation from average for each sample was <20%. Cracks were present on all balloons, but their length was not significantly different between samples. The 5-layer DCBs had the fewest cracks, whereas the 15-layer DCBs had the most cracks. A strong positive correlation (R = 0.896) was identified between fluorescence intensity and drug loading. A relationship between the number of layers and coating uniformity seems to exist, but further investigations are required for confirmation. Fluorescence intensity appears to strongly predict drug loading, demonstrating that fluorescent imaging may be a viable alternative to drug release studies.
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  • 文章类型: Journal Article
    在制药冷冻干燥过程中,批次同质性是重要的质量属性。在这种情况下,边缘小瓶效应是一个具有挑战性的现象。不久,这种效应描述了与架子中间的小瓶相比,架子边缘的小瓶干燥更快,温度更高。Ehlers等人的研究。揭示了这种影响主要源于彼此冷却的相邻小瓶的数量,与中间的小瓶相比,角落和边缘的小瓶减少了。由于环烯烃聚合物(COP)小瓶中传热减少,不利的边缘-小瓶-效应应大大降低,从而允许更好的批次均匀性。在这项重点研究中,玻璃和COP小瓶在满载货架上的这种影响进行比较。还介绍了使用特殊设计的框架将小瓶放置在远处的参考实验。
    In pharmaceutical freeze-drying processes, batch homogeneity is an important quality attribute. In this context, the edge-vial-effect is a challenging phenomenon. Shortly, this effect describes that vials at the edges of the shelf dry faster and at a higher temperature compared to vials in the middle of the shelf. Studies by Ehlers et al. revealed that this effect mainly origins from the number of neighbor vials cooling each other, which is reduced for vials in corners and edges compared to vials in the middle. Due to the reduced heat transfer in cyclic olefin polymer (COP) vials, the adverse edge-vial-effect should be greatly reduced allowing a better batch uniformity. In this focused study, glass and COP vials are compared regarding this effect on a fully loaded shelf. A reference experiment with vials placed at distance using a specially designed frame is presented as well.
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  • 文章类型: Journal Article
    聚(3,4-亚乙基二氧噻吩)聚苯乙烯磺酸盐(PEDOT:PSS)的电镀在许多神经电子应用中是重要的,但是使用常规恒电流方法在大规模微电极阵列(MEA)上实现均匀性是具有挑战性的。在这项研究中,我们通过恒电位方法解决了这一挑战,并在MEA上展示了PEDOT:PSS的高度均匀电镀,超过一百个电极,都是细胞大小的。这种方法的验证包括与恒电流沉积方法的比较,展示无与伦比的沉积产量和均匀性。系统的电化学表征揭示了恒电位沉积涂层的结构和稳定性的相似性。这里开发的进展建立了恒电位方法和详细过程,以实现PEDOT:PSS在大规模MEA上的均匀涂层,在神经电子学中具有广泛的实用性。
    Electroplating of poly(3,4-ethylenedioxythiophene) polystyrene sulfonate (PEDOT:PSS) is important in many neuroelectronic applications but is challenging to achieve uniformity on large-scale microelectrode arrays (MEA) using conventional galvanostatic methods. In this study, we address this challenge through a potentiostatic method and demonstrate highly uniform electroplating of PEDOT:PSS on MEA with more than one hundred electrodes, all at cellular sizes. The validation of this approach involves comparisons with galvanostatic deposition methods, showcasing unparalleled deposition yield and uniformity. Systematic electrochemical characterizations reveal similarities in structure and stability from potentiostatic deposited coatings. The advances developed here establish the potentiostatic method and detailed process to achieve a uniform coating of PEDOT:PSS on large-scale MEA, with broad utility in neuroelectronics.
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  • 文章类型: Journal Article
    路基损伤具有隐蔽性强、难以检测的特点。出于这个原因,冲击成像方法已用于道路基层的检测。本文系统地讨论了采集点的设置,励磁方式和数据处理方法。通过在公路路面基层灌浆养护前后检测中的应用,结果表明该方法简便、准确。检测结果可以以二维图像形式显示,并且易于在道路维护中使用。该方法可用于识别和定位路面基层的损伤,判断路面基层结构的均匀性。还可用于评价灌浆修复后内部损伤的有效性。
    The damage of road base course has the characteristics of strong concealment and difficulty in detecting. For this reason, the impact imaging method has been used for detection of road base course. This paper discussed systematically collection points setting, excitation mode and data processing method. Through the application in testing for highway pavement base before and after grouting maintenance, the results show that the method is simple and accurate. The detection results can be displayed in a two-dimensional image form and it is easy to be used in road maintenance. This method can be used to identify and locate the damages of the pavement base, to judge the uniformity of the pavement base structure. It can also be used to evaluate the effectiveness of internal damage after grouting repairing.
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  • 文章类型: Journal Article
    以高质量为标志的贵金属纳米晶体的胶体合成仍然是一个挑战,量大,和批次之间的一致性。在这里,我们报告了一种自我密封的设置,用于实现强大的,可重复,和可扩展的生产具有18-60nm的均匀和受控尺寸的Ag纳米立方体。与传统的露天设置不同,自密闭系统使其切实可行的稳定反应条件,通过减少挥发性试剂的损失。新设置还使我们能够轻松优化系统中捕获的O2(来自空气)的量,确保单晶晶种的突发成核,随后它们缓慢生长成纳米立方体。最重要的是,新的设置允许在不牺牲均匀性的情况下生产克量的Ag纳米立方体,拐角/边缘锐度,控制尺寸,不同批次的纯度高。如此大量的高质量Ag纳米立方体的可用性预计将大大促进它们在与等离子体相关的应用中的使用。催化作用,和生物医学。
    It remains a challenge to accomplish colloidal synthesis of noble-metal nanocrystals marked by high quality, large quantity, and batch-to-batch consistency. Here we report a self-airtight setup for achieving robust, reproducible, and scalable production of Ag nanocubes with uniform and controlled sizes from 18 to 60 nm. Different from the conventional open-to-air setup, the self-airtight system makes it practical to stabilize the reaction condition by minimizing the loss of volatile reagents. The new setup also allows us to easily optimize the amount of O2 (from air) trapped in the system, ensuring burst nucleation of single-crystal seeds, followed by their slow growth into nanocubes. Most significantly, the new setup allows for the production of Ag nanocubes at gram quantities without sacrificing uniformity, corner/edge sharpness, controlled size, and high purity across different batches. The availability of high-quality Ag nanocubes in such a large quantity is anticipated to substantially boost their use in applications related to plasmonics, catalysis, and biomedicine.
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  • 文章类型: Journal Article
    微机械谐振器作为生物和化学传感器引起了越来越多的兴趣,微悬臂梁是主要的研究热点。最近,集成加热器的谐振微悬臂梁已应用于片上热重分析(TGA)。然而,共振微悬臂梁的质量灵敏度与吸附质量的位置之间存在很强的关系。不同的采样位置会导致灵敏度差异,这将导致质量变化的不准确计算。在这里,提出并开发了具有均匀质量灵敏度和温度分布的集成H形谐振梁,以提高生物/化学传感和TGA应用的准确性。实验证明,与谐振微悬臂梁相比,该谐振梁具有更好的灵敏度和温度分布均匀性。还进行了利用集成谐振梁的气体传感和TGA实验,并表现出良好的测量精度。
    Micromechanical resonators have aroused growing interest as biological and chemical sensors, and microcantilever beams are the main research focus. Recently, a resonant microcantilever with an integrated heater has been applied in on-chip thermogravimetric analysis (TGA). However, there is a strong relationship between the mass sensitivity of a resonant microcantilever and the location of adsorbed masses. Different sampling positions will cause sensitivity differences, which will result in an inaccurate calculation of mass change. Herein, an integrated H-shaped resonant beam with uniform mass sensitivity and temperature distribution is proposed and developed to improve the accuracy of bio/chemical sensing and TGA applications. Experiments verified that the presented resonant beam possesses much better uniformity of sensitivity and temperature distribution compared with resonant microcantilevers. Gas-sensing and TGA experiments utilizing the integrated resonant beam were also carried out and exhibited good measurement accuracy.
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