Quartz

石英
  • 文章类型: English Abstract
    Objective: To observe the changes of lung function and inflammatory factors in rat models of coal workers\' pneumoconiosis at different time points. Methods: In June 2021, 96 healthy male SD rats with SPF grade were divided into 1, 3, and 6-month control group and dust staining group (coal dust group, coal silica dust group, quartz group) according to random number table method, with 8 rats in each group. After one week of adaptive feeding, a one-time non-exposed tracheal perfusion method (1 ml/ piece) was used. The dust dyeing group was given 50 g/L coal dust, coal silica mixed dust and quartz dust suspension, respectively, and the control group was given 0.9% normal saline solution. At 1, 3 and 6 months after perfusion, lung function was detected by animal lung function apparatus, then all lung tissues and alveolar lavage fluid were killed, and lung histopathological morphological changes were observed by HE staining, and the contents of interleukin (IL-1β), IL-18, IL-4 and IL-10 in alveolar lavage fluid were detected by ELISA. One-way analysis of variance was used to compare groups. Two factors (inter-group treatment factor (4 levels) and observation time factor (3 levels) ) were used in the analysis of the effects of inter-group treatment and treatment time on related indicators. Results: HE staining results showed that coal spot appeared in the lung tissue of coal dust group, coal spot and coal silicon nodule appeared in the lung tissue of coal dust group, and silicon nodule appeared in the lung tissue of quartz group. Compared with the control group, the forced vital capacity (FVC) and forced expiratory volume at 0.2 second (FEV(0.2)) of rats in the dust staining group had interaction between the treatment and treatment time (P<0.05). With the increase of dust dyeing time, FVC and FEV(0.2) decreased significantly at 3-6 months of dust dyeing, and the maximum gas volume per minute (MVV) decreased significantly at 1-3 months of dust dyeing (P<0.05). The lowest lung function index was in quartz group, followed by coal-silica group and coal-dust group. There were statistically significant differences in the main effect and interaction effect of the pro-inflammatory factor IL-18 among all groups in treatment and treatment time (IL-18: F=70.79, 45.97, 5.90, P<0.001), and interaction existed. The highest content of inflammatory factors in alveolar lavage fluid of all dust groups was quartz group, followed by coal silica group and coal dust group. There were significant differences in the main effect and interaction effect of anti-inflammatory factors between groups and treatment time (IL-4: F=41.55, 33.01, 5.23, P<0.001, <0.001, <0.001; IL-10: F=7.46, 20.80, 2.91, P=0.002, <0.001, 0.024), and there was interaction. The highest content of anti-inflammatory factor was in quartz group, followed by coal silica group and coal dust group. Conclusion: Lung function decreased and levels of inflammatory fators increased in rat models of coal workers\' pneumoconiosis, with the quartz group being the most severely damaged. Lung function is mainly impaired in thrid-six months, and the content of inflammatory factors begins to change in first-thrid months. MVV are the earliest and most obvious in lung function. IL-18 is suitable for monitoring changes in the pro-inflammatory response of coal workers\' pneumoconiosis, and IL-10 is suitable for monitoring changes in anti-inflammatory response.
    目的: 观察不同时间点大鼠煤工尘肺模型肺功能与炎症因子的变化特点。 方法: 于2021年6月,将96只SPF级健康雄性SD大鼠按随机数字表法分为1、3、6个月对照组和染尘组(煤尘组、煤矽尘组、石英组),每组8只。适应性饲养一周后,采用一次性非暴露式气管灌注法(1 ml/只),染尘组分别给予50 g/L煤尘、煤矽混合尘和石英尘悬浮液,对照组给予0.9%生理盐水溶液。灌注后满1、3、6个月时采用动物肺功能仪检测肺功能,随后全部处死大鼠并取肺组织和肺泡灌洗液,HE染色观察肺组织病理学形态变化,ELISA法检测肺泡灌洗液中细胞介素(IL)-1β、IL-18、IL-4和IL-10的含量。多组间比较用单因素方差分析;组间处理和处理时间对相关指标的影响分析采用两因素[组间处理因素(4个水平)、观察时间因素(3个水平)]4×3析因设计方差分析。 结果: HE染色结果显示,煤尘组大鼠肺组织出现煤斑,煤矽尘组大鼠肺组织出现煤斑和煤矽结节,石英组大鼠肺组织出现矽结节。与对照组比较,各染尘组大鼠用力肺活量(FVC)、第0.2秒用力呼气容积(FEV(0.2))在组间处理和处理时间上存在交互作用(P<0.05)。随着染尘时间的增加,FVC、FEV(0.2)在染尘3至6个月时明显下降,每分钟最大通气量(MVV)在染尘1至3个月时明显下降(P<0.05)。各染尘组大鼠肺功能指标最低的是石英组,其次为煤矽尘组、煤尘组。各组大鼠促炎因子IL-18在组间处理和处理时间的主效应及交互效应上差异均有统计学意义(F=70.79、45.97、5.90,P均<0.001),且存在交互作用。各染尘组肺泡灌洗液中炎症因子含量最高的是石英组,其次为煤矽尘组、煤尘组。各组大鼠抗炎因子在组间处理和处理时间的主效应及交互效应上差异均有统计学意义(IL-4:F=41.55、33.01、5.23,P=<0.001、<0.001、<0.001;IL-10:F=7.46、20.80、2.91,P=0.002、<0.001、0.024),且存在交互作用。各染尘组大鼠抗炎因子含量最高为石英组,其次为煤矽尘组、煤尘组。 结论: 大鼠煤工尘肺各类型均出现肺功能下降和炎症因子含量升高,其中石英组损害最为严重。肺功能主要在3至6月出现损害,炎症因子含量在1至3月就开始发生变化。肺功能指标MVV变化最早、最明显,IL-18适合监测煤工尘肺促炎反应变化,IL-10适合监测抗炎反应变化。.
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  • 文章类型: Journal Article
    富含硅的生物炭(sichar)中的硅在固定重金属和为嗜硅植物提供缓慢释放的生物可利用硅方面起着至关重要的作用。然而,加热速率对硅性能和碳硅相互作用的影响仍不清楚。在这项研究中,稻壳用作富含硅的生物质,以不同的加热速率(每分钟10、30和60°C,和超快速热解),然后进行硅浓度测量等实验,进行了拉曼和XRD表征。结果表明,较快的升温速率降低了热解过程中的碳含量,同时促进了无定形二氧化硅的形成,导致在400°C下制备的二氧化硅中溶解的硅增加了三倍。此外,我们观察到在快速加热下稻壳衍生的生物炭中形成亚稳定的SiO2多晶型物(tridymite),与以前观察到的缓慢加热速率下产生的石英不同。关于CSi关系,更快的加热速率有助于去除表面碳层,暴露下面的硅层。这导致更多的可溶性硅物种和较少的封装硅,导致连续释放和累积硅溶解量增加1.2倍和1.6-1.9倍,分别,比那些在缓慢加热速率衍生的Sichars。因此,这增强了水稻幼苗对硅的吸收。我们的发现表明,超过热解温度,加热速率显着影响硅物种,硅溶解行为,和生物炭的碳硅关系,最终决定了sichars的属性和应用。
    Silicon within Si-rich biochars (sichar) plays a crucial role in immobilizing heavy metals and providing slow-releasing bioavailable silicon for silicophilic plants. However, the impact of heating rate on the silicon properties and carbon‑silicon interactions in sichars remains unclear. In this study, rice husk was used as a silicon-rich biomass to prepare sichars at different heating rates (10, 30 and 60 °C per minute, and ultra-fast-pyrolysis), then experiments such as silicon concentration measurement, Raman and XRD characterization were conducted. The results showed that a faster heating rate reduced the carbon content during pyrolysis while promoted the formation of amorphous silica, resulting in a threefold increase in dissolved silicon in sichars prepared at 400 °C. Additionally, we observed the formation of a meta-stable SiO2 polymorph (tridymite) in rice husk-derived biochars under fast heating, differing from the previously observed quartz generated at slow heating rates. Regarding the CSi relationship, a faster heating rate facilitated the removal of the surface carbon layer, exposing the underlying silicon layer. This led to more soluble silicon species and less encapsulated silicon, resulting in a continuous release and cumulative silicon dissolution amount 1.2 times and 1.6-1.9 times higher, respectively, than those in slow heating rate-derived sichars. Consequently, this enhanced silicon uptake in rice seedlings. Our findings indicate that beyond pyrolysis temperature, the heating rate significantly affects the silicon species, silicon dissolution behavior, and carbon‑silicon relationships of biochar, ultimately determines the properties and applications of sichars.
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  • 文章类型: Journal Article
    城市径流中的微塑料快速破碎并在土壤中积累,可能危及浅层地下水。为了提高对地下水中微塑料运输的认识,进行了柱实验,以比较破碎的微塑料(FMPs~1-µm直径)和球形微塑料(SMPs~1-,10-,和20µm直径)在天然砾石(中和细)和石英砂(粗和中)中。用玻璃珠物理研磨聚苯乙烯微球以模拟快速碎裂过程。通过注入两个孔体积的SMP和FMP,以1.50mday-1的恒定流速进行实验。主要研究结果表明,SMPs显示出更高的突破,与天然砾石中的FMPs相比,可能是由于较大的SMP的尺寸排除。有趣的是,FMP在石英砂中表现出更高的突破,可能是由于翻滚和它们与流动路径对齐的趋势,而两种尺寸(相对于FMP更大和更小)的SMP在石英砂中的去除率更高。因此,由于形状和大小的影响被观察到。
    Microplastics in urban runoff undergo rapid fragmentation and accumulate in the soil, potentially endangering shallow groundwater. To improve the understanding of microplastic transport in groundwater, column experiments were performed to compare the transport behavior of fragmented microplastics (FMPs ∼1-µm diameter) and spherical microplastics (SMPs ∼1-, 10-, and 20-µm diameter) in natural gravel (medium and fine) and quartz sand (coarse and medium). Polystyrene microspheres were physically abraded with glass beads to mimic the rapid fragmentation process. The experiments were conducted at a constant flow rate of 1.50 m day-1 by injecting two pore volumes of SMPs and FMPs. Key findings indicate that SMPs showed higher breakthrough, compared to FMPs in natural gravel, possibly due to size exclusion of the larger SMPs. Interestingly, FMPs exhibited higher breakthrough in quartz sand, likely due to tumbling and their tendency to align with flow paths, while both sizes (larger and smaller relative to FMPs) of SMPs exhibited higher removal in quartz sand. Therefore, an effect due to shape and size was observed.
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  • 文章类型: Journal Article
    氟(19F)NMR正在成为化学中一种宝贵的分析技术,生物化学,结构生物学,材料科学,药物发现,和医学,特别是由于天然存在的氟在生物中固有的稀有性,有机,和无机化合物。这里,我们重新审视了从新的和未使用的玻璃NMR管中氟化物浸出的报道不足的问题。我们表征了在几个小时的过程中从各种类型的新的和未使用的玻璃NMR管中浸出游离氟化物,并将这种污染物量化为在多种玻璃类型和品牌的典型NMR样品体积的微摩尔浓度。我们发现,在我们的实验时间范围内,在石英NMR管中制备的样品无法检测到这种假象。我们还观察到,预浸泡新的玻璃NMR管结合冲洗将这种污染物去除到低于微摩尔水平。鉴于19FNMR在广泛领域的日益普及,一次性筛选管的日益普及,松弛研究和低浓度样品所需的长收集时间,以及在所有核磁共振实验中避免污染的重要性,我们预计,我们的简单的解决方案将是有用的生物分子核磁共振波谱学家。
    Fluorine (19F) NMR is emerging as an invaluable analytical technique in chemistry, biochemistry, structural biology, material science, drug discovery, and medicine, especially due to the inherent rarity of naturally occurring fluorine in biological, organic, and inorganic compounds. Here, we revisit the under-reported problem of fluoride leaching from new and unused glass NMR tubes. We characterised the leaching of free fluoride from various types of new and unused glass NMR tubes over the course of several hours and quantify this contaminant to be at micromolar concentrations for typical NMR sample volumes across multiple glass types and brands. We find that this artefact is undetectable for samples prepared in quartz NMR tubes within the timeframes of our experiments. We also observed that pre-soaking new glass NMR tubes combined with rinsing removes this contamination below micromolar levels. Given the increasing popularity of 19F NMR across a wide range of fields, increasing popularity of single-use screening tubes, the long collection times required for relaxation studies and samples of low concentrations, and the importance of avoiding contamination in all NMR experiments, we anticipate that our simple solution will be useful to biomolecular NMR spectroscopists.
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  • 文章类型: Journal Article
    随着优质原材料的日益枯竭,硅质灰岩,砂岩和其他含有结晶SiO2的难烧原料逐渐被用于生产熟料。这项研究调查了硅质石灰石中石英含量和粒径对煅烧过程和水泥熟料质量的影响。将两种不同的硅质石灰岩研磨至不同的细度,并用其他材料煅烧。采用XRD-Rietveld法对熟料的含量进行了分析,采用激光扫描共聚焦显微镜(LSCM)和场发射扫描电子显微镜(FESEM)对熟料的微观结构进行了观察。这项研究的三个关键成果为硅质石灰石在水泥生产中的使用提供了新的见解,即(i)将硅质石灰石的细度值从0.08毫米筛子上的残留物的15%降低到0%,减少了这些较大的石英颗粒的数量,导致C3S含量增加高达8%,28d抗压强度增加高达4.4Mpa,62.30Mpa;(ii)石英的形态-无论是作为石结节还是单晶-都会影响熟料中C2S团簇的微观结构,发现石结节导致具有更多中间阶段的集群,而大的单晶导致更致密的团簇;(iii)硅质石灰石SL1和SL2的足够细度值是0.08毫米筛子上残留物的5%和7%,分别,可以生产28d抗压强度大于60Mpa的熟料,表明对于硅质石灰石中的不同种类的石英,有一个最佳的研磨解决方案,可以实现熟料质量和能耗之间的平衡,而不必研磨硅质石灰石到非常精细的等级。
    With the increasing depletion of high-quality raw materials, siliceous limestone, sandstone and other hard-to-burn raw materials containing crystalline SiO2 are gradually being used to produce clinker. This study investigates the influence of the quartz content and particle size in siliceous limestone on the calcination process and the resultant quality of cement clinker. Two different siliceous limestones were grinded to different fineness, and calcinated with some other materials. The content of the clinkers was analyzed with the XRD-Rietveld method and the microstructure of the clinkers was observed with laser scanning confocal microscopy (LSCM) and field emission scanning electron microscopy (FESEM). Three key outcomes of this study provide new insights on the use of siliceous limestone in cement production, namely that (i) reducing the fineness values of siliceous limestone from 15% to 0% of residue on a 0.08 mm sieve decreases the quantity of these larger quartz particles, resulting in an increase in C3S content by up to 8% and an increase in 28d compressive strength by up to 4.4 Mpa, which is 62.30 Mpa; (ii) the morphology of quartz-either as chert nodules or single crystals-affects the microstructure of C2S clusters in clinker, finding that chert nodules result in clusters with more intermediate phases, whereas large single crystals lead to denser clusters; (iii) the sufficient fineness values of siliceous limestone SL1 and SL2 are 5% and 7% of residue on a 0.08 mm sieve, respectively, which can produce a clinker with a 28d compressive strength greater than 60 Mpa, indicating that for different kinds of quartz in siliceous limestone, there is an optimum grinding solution that can achieve a balance between clinker quality and energy consumption without having to grind siliceous limestone to very fine grades.
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  • 文章类型: Journal Article
    微塑料(MP)是新兴的污染物,吸引了越来越多的研究人员的兴趣,饮用水在过滤过程中的运输极大地影响了饮用水的安全。选择聚苯乙烯(PS)作为代表,和三种过滤介质(石英砂,沸石,和无烟煤)通常在水生植物中发现。借助DLVO理论和胶体过滤理论,系统地研究了各种过滤介质在各种背景水质条件下PS-MPs的保留方式。结果表明,三种过滤介质的不同结构和元素组成导致它们表现出不同的表面粗糙度和表面电势。过滤介质的更大的表面粗糙度可以为PS-MP提供更多的沉积位置。与石英砂相比,沸石和无烟煤更大的表面粗糙度显着增强了其抑制PS-MPs迁移的能力。然而,表面粗糙度不是影响MPs迁移的唯一因素。无烟煤表面电势的绝对值较低,导致其与PS-MPs之间的DLVO能量明显低于沸石与PS-MPs之间的DLVO能量,这导致无烟煤对PS-MPs的更强保留,具有较低的表面粗糙度,比沸石,具有较高的表面粗糙度。PS-MP在介质中的传输受过滤介质的表面粗糙度和DLVO能量的组合影响。在相同的操作条件下,三种过滤材料对PS-MPs的保留效率遵循石英砂<沸石<无烟煤的顺序。此外,溶液的条件显着影响了PS-MPs在模拟过滤柱内的传输能力。模拟过滤柱中的传输PS-MPs随着溶液离子强度和阳离子化合价的增加而降低。自然,溶解的有机物促进了PS-MPs在过滤层中的转移,腐殖酸比富里酸具有更强的促进作用。研究结果可能为提高过滤器单元保留MP的能力提供有用的见解。
    Microplastics (MPs) are emerging contaminants that are attracting increasing interest from researchers, and the safety of drinking water is greatly affected by their transportation during filtration. Polystyrene (PS) was selected as a representative MPs, and three filter media (quartz sand, zeolite, and anthracite) commonly found in water plants were used. The retention patterns of PS-MPs by various filter media under various background water quality conditions were methodically investigated with the aid of DLVO theory and colloidal filtration theory. The results show that the different structures and elemental compositions of the three filter media cause them to exhibit different surface roughnesses and surface potentials. A greater surface roughness of the filter media can provide more deposition sites for PS-MPs, and the greater surface roughness of zeolite and anthracite significantly enhances their ability to inhibit the migration of PS-MPs compared with that of quartz sand. However, surface roughness is not the only factor affecting the migration of MPs. The lower absolute value of the surface potential of anthracite causes the DLVO energy between it and PS-MPs to be significantly lower than that between zeolite and PS-MPs, which results in stronger retention of PS-MPs by anthracite, which has a lower surface roughness, than zeolite, which has a higher surface roughness. The transport of PS-MPs in the medium is affected by the combination of the surface roughness of the filter media and the DLVO energy. Under the same operating conditions, the retention efficiencies of the three filter materials for PS-MPs followed the order of quartz sand < zeolite < anthracite. Additionally, the conditions of the solution markedly influenced the transport ability of PS-MPs within the simulated filter column. The transport PS-MPs in the simulated filter column decreased with increasing solution ionic strength and cation valence. Naturally, dissolved organic matter promoted the transfer of PS-MPs in the filter layer, and humic acid had a much stronger facilitating impact than fulvic acid. The study findings might offer helpful insight for improving the ability of filter units ability to retain MPs.
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  • 文章类型: Journal Article
    进行不同矿物质的剂量测定,以调查发生核事故时人口接受的剂量。回顾性剂量学是一个不断寻找新材料的领域。沙滩矿物,即石英和锆石,暴露于β和γ辐射并分别研究。研究了β和γ的不同石英峰的热释光(TL)输出的比较。进行了石英峰与锆石峰的TL输出的比较。与由于β而接收的TL输出相比,恒定剂量的γ的TL输出总是更高。
    The dosimetry of different minerals is carried out to investigate the dose received by the population in case of a nuclear accident. Retrospective dosimetry is a field where there is a continuous search to find new materials. Beach sand minerals, namely quartz and zircon, were exposed to beta and gamma radiation and studied separately. A comparison of the thermoluminescence (TL) output of different peaks of quartz for beta and gamma was studied. Comparison of quartz peaks with the TL output of zircon peaks was carried out. TL output for a constant dose of gamma is always higher compared to the TL output received due to beta.
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  • 文章类型: Journal Article
    石英音叉(QTF)是生物传感器应用的一种有前途的仪器,由于其先进的性能,如对物理量的高灵敏度,成本效益,频率稳定性,和高质量的因素。然而,叉子的小尺寸和修改叉的表面的困难限制了它在实验研究中的广泛应用。我们的研究提出了由三个活性层组成的QTF免疫传感器的开发:生物相容性天然黑色素纳米颗粒(MNPs),戊二醛(GLU),和抗IgG层,用于检测免疫球蛋白G(IgG)。MNP功能化后QTF的频移,GLU激活,和抗IgG固定用AsensisQTFF-master装置测量。使用已在最佳条件下修改的QTF免疫传感器,评价了QTF免疫传感器检测IgG的性能。因此,使用COMSOLMultiphysics软件程序(COMSOL许可证号。2102058)来模拟沉积层对QTF共振频率的影响。实验结果,证明了QTF表面功能化过程中每一层的频率变化,证实了模拟模型的预测。与实验结果相比,MNP功能化的QTF生物传感器的建模误差为0.05%。本研究验证了一个仿真模型,该模型展示了基于仿真的方法优化QTF生物传感器的优势。从而减少了大量实验室工作的需要。
    The quartz tuning fork (QTF) is a promising instrument for biosensor applications due to its advanced properties such as high sensitivity to physical quantities, cost-effectiveness, frequency stability, and high-quality factor. Nevertheless, the fork\'s small size and difficulty in modifying the prongs\' surfaces limit its wide use in experimental research. Our study presents the development of a QTF immunosensor composed of three active layers: biocompatible natural melanin nanoparticles (MNPs), glutaraldehyde (GLU), and anti-IgG layers, for the detection of immunoglobulin G (IgG). Frequency shifts of QTFs after MNP functionalization, GLU activation, and anti-IgG immobilization were measured with an Asensis QTF F-master device. Using QTF immunosensors that had been modified under optimum conditions, the performance of QTF immunosensors for IgG detection was evaluated. Accordingly, a finite element method (FEM)-based model was produced using the COMSOL Multiphysics software program (COMSOL License No. 2102058) to simulate the effect of deposited layers on the QTF resonance frequency. The experimental results, which demonstrated shifts in frequency with each layer during QTF surface functionalization, corroborated the simulation model predictions. A modelling error of 0.05% was observed for the MNP-functionalized QTF biosensor compared to experimental findings. This study validated a simulation model that demonstrates the advantages of a simulation-based approach to optimize QTF biosensors, thereby reducing the need for extensive laboratory work.
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  • 文章类型: Journal Article
    目标:先前的放射学和组织病理学研究表明,可吸入结晶二氧化硅(RCS)的过度暴露已导致当代美国煤矿工人中尘肺病的死灰复燃,阿巴拉契亚中部的严重疾病患病率较高。我们试图更好地了解美国地下煤矿工人的RCS暴露情况。
    方法:我们分析了RCS水平,用可吸入石英测量,来自1982年至2021年的煤矿粉尘合规数据。
    结果:我们分析了来自5064个美国地下煤矿的322919个可吸入石英样品。阿巴拉契亚中部矿山的平均可吸入石英百分比和质量浓度始终高于美国其他地区。平均矿级可吸入石英质量浓度随时间显著下降,从1982年的0.116毫克/立方米到阿巴拉契亚中部矿山的低至0.017毫克/立方米,美国其他地区从1983年的0.089mg/m3到2020年的0.015mg/m3。较小的地雷大小,位于阿巴拉契亚中部,缺乏矿山安全委员会和较薄的煤层预示着较高的可吸入石英质量浓度。
    结论:这些数据基本上支持RCS过度暴露与美国煤工尘肺复苏之间的关联,特别是在阿巴拉契亚中部的小型矿山。
    OBJECTIVE: Previous radiologic and histopathologic studies suggest respirable crystalline silica (RCS) overexposure has been driving the resurgence of pneumoconiosis among contemporary US coal miners, with a higher prevalence of severe disease in Central Appalachia. We sought to better understand RCS exposure among US underground coal miners.
    METHODS: We analysed RCS levels, as measured by respirable quartz, from coal mine dust compliance data from 1982 to 2021.
    RESULTS: We analysed 322 919 respirable quartz samples from 5064 US underground coal mines. Mean mine-level respirable quartz percentage and mass concentrations were consistently higher for Central Appalachian mines than the rest of the USA. Mean mine-level respirable quartz mass concentrations decreased significantly over time, from 0.116 mg/m3 in 1982 to as low as 0.017 mg/m3 for Central Appalachian mines, and from 0.089 mg/m3 in 1983 to 0.015 mg/m3 in 2020 for the rest of the USA. Smaller mine size, location in Central Appalachia, lack of mine safety committee and thinner coal seams were predictive of higher respirable quartz mass concentrations.
    CONCLUSIONS: These data substantially support the association between RCS overexposure and the resurgence of coal workers\' pneumoconiosis in the USA, particularly in smaller mines in Central Appalachia.
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  • 文章类型: Journal Article
    石英晶体的微加工技术越来越重要,因为石英MEMS器件的小型化对于确保便携式和可穿戴电子产品的发展至关重要。然而,直到现在,没有关于石英器件制造尺寸补偿的报道。因此,本文研究了使用Au/Cr金属硬掩模制作深沟槽图形的Z形切割石英晶体衬底的湿法蚀刻工艺,并提出了第一种石英制造尺寸补偿策略。实验研究了各种尺寸的硬掩模图案对湿法蚀刻中产生的底切的尺寸效应。用宽度从3μm到80μm的初始通孔掩蔽的石英晶片在缓冲氧化物蚀刻溶液中进行蚀刻(BOE,HF:NH4F=3:2)在80°C下进行长时间蚀刻(>95分钟)。发现较大的硬掩模宽度导致较小的底切,硬掩模宽度的30μm差异将导致底切增加17.2%。特别是,底切主要在蚀刻的前5分钟形成,蚀刻速率相对较高,为0.7μm/min(max)。然后,蚀刻率迅速下降到27%。此外,基于蚀刻宽度补偿和蚀刻位置补偿,提出了石英晶体器件制造的新解决方案。并将这两种补偿方案用于制造谐振频率为32.768kHz的超小型石英晶体音叉。有了这些方法,器件关键部分的实际刻蚀尺寸仅偏离设计尺寸0.7%。与未补偿的相比,二次光刻蚀刻工艺的图案位置对称性提高了96.3%。它证明了提高石英晶体器件制造精度的巨大潜力。
    Microfabrication technology with quartz crystals is gaining importance as the miniaturization of quartz MEMS devices is essential to ensure the development of portable and wearable electronics. However, until now, there have been no reports of dimension compensation for quartz device fabrication. Therefore, this paper studied the wet etching process of Z-cut quartz crystal substrates for making deep trench patterns using Au/Cr metal hard masks and proposed the first quartz fabrication dimension compensation strategy. The size effect of various sizes of hard mask patterns on the undercut developed in wet etching was experimentally investigated. Quartz wafers masked with initial vias ranging from 3 μm to 80 μm in width were etched in a buffered oxide etch solution (BOE, HF:NH4F = 3:2) at 80 °C for prolonged etching (>95 min). It was found that a larger hard mask width resulted in a smaller undercut, and a 30 μm difference in hard mask width would result in a 17.2% increase in undercut. In particular, the undercuts were mainly formed in the first 5 min of etching with a relatively high etching rate of 0.7 μm/min (max). Then, the etching rate decreased rapidly to 27%. Furthermore, based on the etching width compensation and etching position compensation, new solutions were proposed for quartz crystal device fabrication. And these two kinds of compensation solutions were used in the fabrication of an ultra-small quartz crystal tuning fork with a resonant frequency of 32.768 kHz. With these approaches, the actual etched size of critical parts of the device only deviated from the designed size by 0.7%. And the pattern position symmetry of the secondary lithography etching process was improved by 96.3% compared to the uncompensated one. It demonstrated significant potential for improving the fabrication accuracy of quartz crystal devices.
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