Tungsten Compounds

钨化合物
  • 文章类型: Journal Article
    最近,抗生素微污染物对环境和人类健康的有害影响已成为一个主要问题。为了应对这一挑战,基于半导体的光催化已成为环境修复的有前途的解决方案。我们的研究开发了Bi2WO6/g-C3N4(BWCN)光催化剂,具有独特的特性,如反应性表面位点,提高电荷转移效率,和加速光生电子-空穴对的分离。BWCN用于在不同水源中氧化四环素抗生素(TCA)。按以下顺序显示出显着的TCA去除效率:地表水(99.8%)>污水(88.2%)>医院用水(80.7%)。Further,可重复使用性测试表明BWCN在三个循环后的持续性能,在地表水中的去除效率分别为87.3、71.2和65.9%,污水,医院的水,分别。提出了一种光催化机理,集中在反应性自由基和TCA分子之间的相互作用。此外,测定了TCA光降解过程中产生的转化产物,以及对抗生素污染物潜在风险评估的讨论。本研究介绍了一种利用BWCN光催化剂的方法,在处理各种废水来源的TCA方面具有广阔的应用前景。
    Recently, the hazardous effects of antibiotic micropollutants on the environment and human health have become a major concern. To address this challenge, semiconductor-based photocatalysis has emerged as a promising solution for environmental remediation. Our study has developed Bi2WO6/g-C3N4 (BWCN) photocatalyst with unique characteristics such as reactive surface sites, enhanced charge transfer efficiency, and accelerated separation of photogenerated electron-hole pairs. BWCN was utilized for the oxidation of tetracycline antibiotic (TCA) in different water sources. It displayed remarkable TCA removal efficiencies in the following order: surface water (99.8%) > sewage water (88.2%) > hospital water (80.7%). Further, reusability tests demonstrated sustained performance of BWCN after three cycles with removal efficiencies of 87.3, 71.2 and 65.9% in surface water, sewage, and hospital water, respectively. A proposed photocatalytic mechanism was delineated, focusing on the interaction between reactive radicals and TCA molecules. Besides, the transformation products generated during the photodegradation of TCA were determined, along with the discussion on the potential risk assessment of antibiotic pollutants. This study introduces an approach for utilizing BWCN photocatalyst, with promising applications in the treatment of TCA from various wastewater sources.
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  • 文章类型: Journal Article
    钨酸锌是一种以其有利的光催化作用而闻名的半导体,光致发光,和闪烁特性,加上其相对较低的成本,降低毒性,在生物和催化环境中的高稳定性。特别是,钨酸锌表现出闪烁特性,即吸收高能辐射如x射线时发出可见光的能力,这不仅导致了辐射探测器的应用,还导致了生物医学应用,包括将光学光传递到深层组织,如光动力疗法和光遗传学。这里,我们报告了通过优化但简便的方法合成钨酸锌纳米棒,这允许通过溶液pH的合理变化对合成后的各向异性基序的纵横比进行综合控制。我们研究了纵横比对其所得光致发光和放射性发光特性的影响。我们进一步证明了这些钨酸锌纳米棒在生物医学应用中的潜力,例如用于癌症治疗的光动力疗法,通过分析它们在细胞系和神经元中的毒理学特征。
    Zinc tungstate is a semiconductor known for its favorable photocatalytic, photoluminescence, and scintillation properties, coupled with its relatively low cost, reduced toxicity, and high stability in biological and catalytic environments. In particular, zinc tungstate evinces scintillation properties, namely the ability to emit visible light upon absorption of energetic radiation such as x rays, which has led to applications not only as radiation detectors but also for biomedical applications involving the delivery of optical light to deep tissue, such as photodynamic therapy and optogenetics. Here, we report on the synthesis of zinc tungstate nanorods generated via an optimized but facile method, which allows for synthetic control over the aspect ratio of the as-synthesized anisotropic motifs via rational variation of the solution pH. We investigate the effect of aspect ratio on their resulting photoluminescent and radioluminescent properties. We further demonstrate the potential of these zinc tungstate nanorods for biomedical applications, such as photodynamic therapy for cancer treatment, by analyzing their toxicological profile within cell lines and neurons.
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  • 文章类型: Journal Article
    在这里,我们报告了基于液滴的摩擦电纳米发电机(TENG)中的液固相互作用,用于估计人类Na/K水平。利用PVDF-HFP封装的WS2作为DTENG中的活性层导致在水滴撞击期间产生电信号。与对照器件的比较表明,PVDF-HFP/WS2复合材料的表面质量和介电性质在很大程度上决定了DTENG的性能。DTENG对水质具有出色的敏感性,表明其在水质测试中的应用前景广阔。此外,已经见证了输出信号的变化,水中离子浓度(Na或K)的变化最小,并通过液-固相互作用期间的电荷转移和离子转移过程来解释。研究表明,离子迁移率在很大程度上影响PVDF-HFP/WS2活性层上的离子吸附过程,从而为Na和K等多种离子产生不同的输出曲线。在此之后,DTENG特性已被用于人工尿液,其中已记录了不同的输出信号以了解尿液中Na离子浓度的变化。因此,在DTENG中部署PVDF-HFP/WS2在分析体液离子特性方面具有广阔的应用前景。
    Here we report the liquid-solid interaction in droplet-based triboelectric nanogenerators (TENG) for estimation of human Na+/K+levels. The exploitation of PVDF-HFP encapsulated WS2as active layer in the droplet-based TENG (DTENG) leads to the generation of electrical signal during the impact of water droplet. Comparison over the control devices indicates that surface quality and dielectric nature of the PVDF-HFP/WS2composite largely dictates the performance of the DTENG. The demonstration of excellent sensitivity of the DTENG towards water quality indicates its promising application towards water testing. In addition, the alteration in output signal with slightest variation in ionic concentration (Na+or K+) in water has been witnessed and is interpreted with charge transfer and ion transfer processes during liquid-solid interaction. The study reveals that the ion mobility largely affects the ion adsorption process on the active layer of PVDF-HFP/WS2and thus generates distinct output profiles for diverse ions like Na+and K+. Following that, the DTENG characteristics have been exploited to artificial urine where the varying output signals have been recorded for variation in urinary Na+ion concentration. Therefore, the deployment of PVDF-HFP/WS2in DTENG holds promising application towards the analyse of ionic characteristics of body fluids.
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  • 文章类型: Journal Article
    多金属氧酸盐(POM)由于其结构可设计性而引起了极大的关注,成分多样性和巨大的潜在应用。作为POM不可或缺的分支,硒钨酸盐(SeTs)已被广泛合成。一些SeT已被用作检测生物标志物的传感材料(例如,代谢物,荷尔蒙,癌症标志物)。为了全面了解基于SeT的传感材料的进步,我们概述了基于SeT的生物传感器的传感性能和机理。基于SeT的生物传感器分为电化学催化生物传感器,电化学亲和生物传感器,“关闭”荧光生物传感器和“打开”荧光生物传感器。我们预计基于SeT的生物传感器在可穿戴和可植入传感技术中的广阔潜力,有望促进基于SeT的生物传感器的重大突破。
    Polyoxometalates (POMs) have drawn significant attention on account of their structural designability, compositional diversity and great potential applications. As an indispensable branch of POMs, selenotungstates (SeTs) have been synthesized extensively. Some SeTs have been applied as sensing materials for detecting biomarkers (e.g., metabolites, hormones, cancer markers). To gain a comprehensive understanding of advancements in SeT-based sensing materials, we present an overview that encapsulates the sensing performances and mechanisms of SeT-based biosensors. SeT-based biosensors are categorized into electrochemical catalytic biosensors, electrochemical affinity biosensors, \"turn-off\" fluorescence biosensors and \"turn-on\" fluorescence biosensors. We anticipate the expansive potential of SeT-based biosensors in wearable and implantable sensing technologies, which promises to catalyze significant breakthroughs in SeT-based biosensors.
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  • 文章类型: Journal Article
    背景:伴有牙龈凹陷的慢性/非龋齿宫颈病变可能需要牙科和牙周重建治疗,其中翼片/移植物可以放置成与牙科填充材料接触。在愈合早期阶段的人牙龈成纤维细胞(HGF-1)响应可根据用于固化牙科复合材料的程序而变化。此外,氧气扩散到牙科复合材料中抑制聚合反应,产生呈现残余未反应单体的氧抑制层(OIL)。这项研究的目的是评估不同的抛光技术和油对HGF-1的影响。
    方法:采用不同技术抛光的复合圆盘(金刚石橡胶,磨料盘和碳化钨毛刺)被使用。使用具有和不具有OIL的另外的未抛光的光滑组作为对照。通过接触角测量和SEM分析其亲水性和表面形貌对样品进行物理表征,分别;然后从细胞毒性和基因表达方面分析了在不同底物上培养时HGF-1的生物反应。
    结果:涂饰系统导致润湿性发生变化,即使与扩散论文的结果没有比例关系,在用一步金刚石橡胶和研磨盘抛光的表面上出现更大的增殖,以及甘油层的直接作用,证实表面粗糙度可以严重影响HGF-1的生物学响应。
    结论:表面润湿性以及细胞行为似乎受到用于最终成形修复体的整理系统的选择的影响。尤其是,油的存在在人牙龈成纤维细胞方面起负面因素的作用。当修复体直接与软组织细胞接触时,本研究可能会提供有关复合材料最佳抛光系统的第一份临床指导。了解HGF-1的行为可以帮助确定抛光治疗以直接恢复与牙龈凹陷相关的龋齿/非龋齿宫颈病变。
    BACKGROUND: Carious/Non-carious cervical lesions with gingival recessions may require both dental and periodontal reconstructive therapy, where flaps/grafts may be placed in contact with a dental filling material. Human Gingival Fibroblasts (HGF-1) response during the early phase of healing could vary according to the procedures employed to cure the dental composite. Moreover, oxygen diffusion into dental composite inhibits the polymerization reaction, creating an oxygen-inhibited layer (OIL) that presents residual unreacted monomers. The aim of this study was to assess the effect of different polishing techniques and OIL on HGF-1.
    METHODS: Composite discs polished with different techniques (diamond rubber, abrasive discs and tungsten carbide burr) were used. An additional not polished smooth group obtained with and without OIL was used as control. Samples were physically characterized through the analysis of their hydrophilicity and surface topography through contact angle measurement and SEM, respectively; afterwards the biologic response of HGF-1 when cultured on the different substrates was analyzed in terms of cytotoxicity and gene expression.
    RESULTS: The finishing systems caused alterations to the wettability, even if without a proportional relation towards the results of the proliferation essay, from which emerges a greater proliferation on surfaces polished with one-step diamond rubber and with abrasive discs as well as a direct effect of the glycerin layer, confirming that surface roughness can heavily influence the biological response of HGF-1.
    CONCLUSIONS: Surfaces wettability as well as cellular behavior seem to be affected by the selection of the finishing system used to lastly shape the restoration. Especially, the presence of OIL act as a negative factor in the regards of human gingival fibroblasts. The present study may provide the first clinical instruction regarding the best polishing system of composite material when the restoration is placed directly in contact with soft tissue cells. Understanding HGF-1 behavior can help identifying the polishing treatment for direct restoration of carious/non-carious cervical lesions associated with gingival recessions.
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  • 文章类型: Journal Article
    方法:一名41岁的男子通过用高速金属毛刺将其切掉,从左手食指上取下了一个碳化钨戒指。两天后,患者出现粉红色和灌注的左食指,环区域周围有干性坏疽,活动屈伸肌腱偏移,远端感觉下降。24小时内,伤口发展为湿性坏疽和弥漫性紫癜,需要截肢。
    结论:在回顾了以前记录的去除碳化钨环的方法之后,作者认为,临床医生应该认识到与使用高速金属毛刺相关的潜在并发症.
    METHODS: A 41-year-old man removed a tungsten carbide ring from his left index finger by cutting it off with a high-speed metal burr. The patient presented two days later with a pink and perfused left index finger with circumferential dry gangrene along the area of the ring, active flexor and extensor tendon excursion, and decreased sensation distally. Within 24 hours, the wound developed into wet gangrene and diffuse cyanosis requiring amputation.
    CONCLUSIONS: After reviewing previously documented methods to remove tungsten carbide rings, the authors conclude clinicians should be cognizant of the potential complications associated with the use of a high-speed metal burr.
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  • 文章类型: Journal Article
    乳清蛋白β-乳球蛋白(βLG)在神经退行性疾病中形成与淀粉样原纤维相似的原纤维,因为它具有较高的β-折叠倾向。这项研究阐明了理解不同的无机Keggin多金属氧酸盐(POM)与蛋白质βLG原纤维的相互作用。POM,如磷钼酸(PMA),硅钼酸(SMA),钨硅酸(TSA),和磷钨酸(PTA)由于其固有的较高阴离子电荷而被使用。通过荧光光谱和硫黄素T测定监测βLG单体和原纤维的相互作用研究,以初步阐明POM的结合能力。POM和βLG的结合也通过分子对接研究得到证实。Zeta电位研究表明,静电介导的POM与蛋白质原纤维的相互作用更高。等温滴定量热法(ITC)研究表明,含钼的POM对蛋白质原纤维的亲和力高于钨。这项研究可以帮助理解食品级蛋白质原纤维的形成,这些原纤维在食品工业中具有深远的意义。
    The whey protein β-lactoglobulin (βLG) forms fibrils similar to the amyloid fibrils in the neurodegenerative diseases due to its higher predisposition of β-sheets. This study shed light on the understanding different inorganic Keggin polyoxometalates (POMs) interaction with the protein βLG fibrils. POMs such as Phosphomolybdic acid (PMA), silicomolybdic acid (SMA), tungstosilicic acid (TSA), and phosphotungstic acid (PTA) were used due to their inherent higher anionic charges. The interaction studies were monitored with fluorescence spectra and Thioflavin T assay for both the βLG monomers and the fibrils initially to elucidate the binding ability of the POMs. The binding of POMs and βLG is also demonstrated by molecular docking studies. Zeta potential studies showed the electrostatic mediated higher interactions of the POMs with the protein fibrils. Isothermal titration calorimetry (ITC) studies showed that the molybdenum containing POMs have higher affinity to the protein fibrils than the tungsten. This study could help understanding formation of food grade protein fibrils which have profound importance in food industries.
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  • 文章类型: Journal Article
    近年来,通过高级氧化工艺去除废水中的有机污染物,尤其是光催化,由于其生态友好性和低成本,已成为一种有意义的方法。在这里,交错II型Bi2WO6/WO3异质结光催化剂是通过简单的水热途径制备的,并通过现代物理化学方法进行了研究(X射线衍射,扫描电子显微镜,低温氮气吸附-脱附,和漫反射光谱)。在最佳反应条件下,优化的BWOW-5光催化剂在180min内表现出H2O2辅助的光催化亚甲基蓝去除效率为94.1%(k=0.01414min-1),由于光生电荷载流子的有效分离,其远高于未改性的Bi2WO6和WO3。捕获实验表明,光生羟基自由基和空穴在光降解反应中起关键作用。此外,优化的BWOW-5异质结光催化剂在H2O2辅助降解其他污染物方面表现出优异的活性,即苯酚,异烟肼,左氧氟沙星,和二苯并噻吩的去除率分别为63.1、73.6、95.0和72.4%,分别。这项研究为基于Bi2WO6的多功能光催化复合材料提供了一种设计策略,该复合材料具有改善的有机污染物降解活性。
    In recent years, the removal organic pollutants from wastewater by advanced oxidation processes, especially photocatalysis, has become a meaningful approach due to its eco-friendliness and low cost. Herein, staggered type-II Bi2WO6/WO3 heterojunction photocatalysts were prepared by a facile hydrothermal route and investigated by modern physicochemical methods (X-ray diffraction, scanning electron microscopy, low-temperature nitrogen adsorption-desorption, and diffuse reflectance spectroscopy). The optimized BWOW-5 photocatalyst exhibited a H2O2-assisted photocatalytic methylene blue removal efficiency of 94.1% (k = 0.01414 min-1) within 180 min under optimal reaction conditions, which is much higher than that of unmodified Bi2WO6 and WO3 due to efficient separation of the photogenerated charge carriers. The trapping experiments demonstrated that photogenerated hydroxyl radicals and holes play a key role in the photodegradation reaction. Moreover, the optimized BWOW-5 heterojunction photocatalyst exhibited excellent activity in the H2O2-assisted degradation of other pollutants, namely phenol, isoniazid, levofloxacin, and dibenzothiophene with the removal rate of 63.1, 73.6, 95.0, and 72.4%, respectively. This investigation offers a design strategy for Bi2WO6-based multifunctional photocatalytic composites with improved activity for organic pollutant degradation.
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  • 文章类型: Journal Article
    通过固态反应法合成了超高热稳定的Ca2MgWO6:xSm3(x=0.5、0.75、1、1.25和1.5mol%)双钙钛矿荧光粉。通过将磷光体的X射线衍射(XRD)图案与标准参考文件进行比较来确认产物形成。结构,形态学,热,用XRD对所制备的荧光粉的光学性能进行了详细的研究,傅里叶变换红外光谱,扫描电子显微镜,漫反射光谱,热重分析(TGA),光致发光发射,和温度相关的PLE(TDPL)。可以看出,对于近紫外激发,磷光体在微红色区域显示出发射,具有中等的显色指数值和高色纯度。发现优化的磷光体(x=1.25mol%)具有3.31eV的直接光学带隙。TGA研究表明优化的磷光体具有惊人的热稳定性。此外,由于声子辅助的辐射跃迁升高,在TDPL中观察到接近零的热猝灭。此外,发现反斯托克斯和斯托克斯发射峰对温度变化敏感,并遵循玻尔兹曼型分布。所有这些显著的性质将使所制备的磷光体成为多场应用的合适候选物和用于进一步开发的令人着迷的材料。
    Ultra-high thermally stable Ca2MgWO6:xSm3+ (x = 0.5, 0.75, 1, 1.25, and 1.5 mol%) double perovskite phosphors were synthesized through solid-state reaction method. Product formation was confirmed by comparing the X-ray diffraction (XRD) patterns of the phosphors with the standard reference file. The structural, morphological, thermal, and optical properties of the prepared phosphor were examined in detail using XRD, Fourier transform infrared spectra, scanning electron microscopy, diffused reflectance spectra, thermogravimetric analysis (TGA), photoluminescence emission, and temperature-dependent PLE (TDPL). It was seen that the phosphor exhibited emission in the reddish region for the near-ultraviolet excitation with moderate Colour Rendering Index values and high colour purity. The optimized phosphor (x = 1.25 mol%) was found to possess a direct optical band gap of 3.31 eV. TGA studies showed the astonishing thermal stability of the optimized phosphor. Additionally, near-zero thermal quenching was seen in TDPL due to elevated phonon-assisted radiative transition. Furthermore, the anti-Stokes and Stokes emission peaks were found to be sensitive toward the temperature change and followed a Boltzmann-type distribution. All these marked properties will make the prepared phosphors a suitable candidate for multifield applications and a fascinating material for further development.
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  • 文章类型: Journal Article
    黑钨矿(FeWO4),一种典型的多金属氧酸盐,作为多相催化剂的吉祥候选者,由于其高化学稳定性和电子特性。然而,FeWO4中的缺电子表面活性Fe物种不足以通过Fe氧化还原介导的类Fenton催化反应裂解H2O2。在这里,我们将硫原子掺杂到FeWO4催化剂中,以改善FeWO4的电子结构,用于H2O2活化和磺胺甲恶唑(SMX)降解。此外,在S掺杂的FeWO4上进行自旋态重构可以有效地改善Fe在d轨道上的电子结构,从而增强H2O2活化。S掺杂还加速了硫物种转化过程中的电子转移,促进Fe(III)向Fe(II)的循环。因此,与FeWO4相比,掺杂S的FeWO4使类Fenton反应增强了近两个数量级。重要的是,在实际水样中,开发的S掺杂FeWO4在40分钟内对SMX的去除效率约为100%。这强调了其广泛的pH适应性,强大的催化稳定性,和耐浸出性。还研究了水成分对S掺杂FeWO4性能的基体效应,结果表明,一定量的Cl-,SO42-,NO3-,HCO3-和PO43-对SMX的降解作用可忽略不计。理论计算证实,S掺杂的FeWO4中Fe中心的独特自旋态重构有利于H2O2的分解。这一发现为Fenton类反应中S掺杂的催化活性增强提供了新的机理见解,并为扩大FeWO4在废水处理中的应用铺平了道路。
    Wolframite (FeWO4), a typical polyoxometalate, serves as an auspicious candidate for heterogeneous catalysts, courtesy of its high chemical stability and electronic properties. However, the electron-deficient surface-active Fe species in FeWO4 are insufficient to cleave H2O2 via Fe redox-mediated Fenton-like catalytic reaction. Herein, we doped Sulfur (S) atom into FeWO4 catalysts to refine the electronic structure of FeWO4 for H2O2 activation and sulfamethoxazole (SMX) degradation. Furthermore, spin-state reconstruction on S-doped FeWO4 was found to effectively refine the electronic structure of Fe in the d orbital, thereby enhancing H2O2 activation. S doping also accelerated electron transfer during the conversion of sulfur species, promoting the cycling of Fe(III) to Fe(II). Consequently, S-doped FeWO4 bolstered the Fenton-like reaction by nearly two orders of magnitude compared to FeWO4. Significantly, the developed S-doped FeWO4 exhibited a remarkable removal efficiency of approximately 100% for SMX within 40 min in real water samples. This underscores its extensive pH adaptability, robust catalytic stability, and leaching resistance. The matrix effects of water constituents on the performance of S-doped FeWO4 were also investigated, and the results showed that a certain amount of Cl-, SO42-, NO3-, HCO3- and PO43- exhibited negligible effects on the degradation of SMX. Theoretical calculations corroborate that the distinctive spin-state reconstruction of Fe center in S-doped FeWO4 is advantageous for H2O2 decomposition. This discovery offers novel mechanistic insight into the enhanced catalytic activity of S doping in Fenton-like reactions and paves the way for expanding the application of FeWO4 in wastewater treatment.
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