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1.
Phys Chem Chem Phys ; 20(8): 5818-5826, 2018 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-29411797

RESUMO

In this article, we report the preparation of a TiO2 nanotube array (TNA) film used as a transparent electrochromic material and a TNA/polyaniline patterned hybrid electrochromic film utilized as an information display material. The TNA film was fabricated by an anodizing process, and a surface patterned TNA with extreme wettability contrast (hydrophilic/hydrophobic) on a TNA surface through self-assembly (SAM) and photocatalytic lithography is fabricated. Then the TNA/polyaniline hybrid film was prepared by electrodeposition of aniline in an aqueous solution. Finally, the electrochromic properties of the TNA film and the TNA/polyaniline hybrid film were investigated. Compared with neat TNA film and polyaniline (PANI) films, the hybrid film shows a much higher optical contrast in the near infrared range. The TNA/polyaniline hybrid film shows higher coloration efficiencies of 24.4 cm2 C-1 at a wavelength of 700 nm and 17.1 cm2 C-1 at a wavelength of 1050 nm compared to the TNA coloration efficiency. The color switching time (20.9 s or 22.9 s) of TNA/polyaniline is faster than TNA.

2.
Phys Chem Chem Phys ; 16(38): 20828-33, 2014 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-25167075

RESUMO

In this paper, we report on the hydrogen photochromism in Nb2O5 powders with different structures. Four different powder phases were prepared by calcining Nb2O5·nH2O powders at various temperatures, and their morphology, structure, and electronic band structure were characterized by scanning electron microscopy, structural analyses, thermogravimetric analysis, differential scanning calorimetry, and optical spectroscopy. Nb2O5 powders with different structures and very different properties were formed after different high-temperature treatments of the polymorphous oxide. A pronounced photochromic effect was observed in the M and H phases of Nb2O5, whereas the other phases exhibited poor photochromic responses. Because photochromism arises due to the detachment of hydrogen atoms under the action of light from hydrogen donor molecules previously adsorbed on the oxide surface, the electronic band structure and the morphology have strong influences on the photochromic properties of Nb2O5 powders. For these reasons, a pronounced photochromic effect was achieved in the H phase.

3.
Radiat Oncol ; 19(1): 93, 2024 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-39049106

RESUMO

BACKGROUND: Conventional single-energy CT can only provide a raw estimation of electron density (ED) for dose calculation by developing a calibration curve that simply maps the HU values to ED values through their correlations. Spectral CT, also known as dual-energy CT (DECT) or multi-energy CT, can generate a series of quantitative maps, such as ED maps. Using spectral CT for radiotherapy simulations can directly acquire ED information without developing specific calibration curves. The purpose of this study is to assess the feasibility of utilizing electron density (ED) maps generated by a novel dual-layer detector spectral CT simulator for dose calculation in radiotherapy treatment plans. METHODS: 30 patients from head&neck, chest, and pelvic treatment sites were selected retrospectively, and all of them underwent spectral CT simulation. Treatment plans based on conventional CT images were transplanted to ED maps with the same structure set, including planning target volume (PTV) and organs at risk (OARs), and the dose distributions were then recalculated. The differences in dose and volume histogram (DVH) parameters of the PTV and OARs between the two types of plans were analyzed and compared. Besides, gamma analysis between these plans was performed by using MEPHYSTO Navigator software. RESULTS: In terms of PTV, the homogeneity index (HI), gradient index (GI), D2%, D98%, and Dmean showed no significant difference between conventional plans and ED plans. For OARs, statistically significant differences were observed in parotids D50%, brainstem in head&neck plans, spinal cord in chest plans and rectum D50% in pelvic plans, whereas the variance remained minor. For the rest, the DVH parameters exhibited no significant difference between conventional plans and ED plans. All of the mean gamma passing rates (GPRs) of gamma analysis were higher than 90%. CONCLUSION: Compared to conventional treatment plans relying on CT images, plans utilizing ED maps demonstrated similar dosimetric quality. However, the latter approach enables direct utilization in dose calculation without the requirements of establishing and selecting a specific Hounsfield unit (HU) to ED calibration curve, providing an advantage in clinical applications.


Assuntos
Elétrons , Estudos de Viabilidade , Órgãos em Risco , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador , Tomografia Computadorizada por Raios X , Humanos , Planejamento da Radioterapia Assistida por Computador/métodos , Tomografia Computadorizada por Raios X/métodos , Estudos Retrospectivos , Elétrons/uso terapêutico , Órgãos em Risco/efeitos da radiação , Radioterapia de Intensidade Modulada/métodos , Neoplasias de Cabeça e Pescoço/radioterapia , Neoplasias de Cabeça e Pescoço/diagnóstico por imagem , Neoplasias/radioterapia , Neoplasias/diagnóstico por imagem , Masculino , Feminino
4.
Heliyon ; 9(8): e18992, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37609400

RESUMO

With the rapid development of industry, the increasing discharge of sewage causes the detection of water quality to be of increasing importance. Potassium dichromate titration is one of the most important testing methods in water quality detection; the ability to accurately identify the titration end-point of potassium dichromate is currently a research challenge. To identify titration end-point quickly and accurately, this study proposes a ResNet14Attention network, which utilizes residual modules that focus on original image information and an attention mechanism that focuses highly on classification targets. The proposed ResNet14Attention network is compared with 12 convolutional neural networks such as ResNet series networks, VGG, and GoogLeNet. The results of comparison experiments reveal that only the proposed ResNet14Attention network has the highest training and testing accuracy of 100% among all convolutional neural networks in the comparison experiment; the proposed ResNet14Attention network has the highest training speed compared to all the networks that over 90% accuracy.

5.
J Colloid Interface Sci ; 636: 351-362, 2023 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-36638574

RESUMO

Dual-band electrochromic materials (DBEMs) are of utmost importance for smart windows to realize independent control of the visible (VIS) and near-infrared (NIR) light. However, very few single-component DBEMs are capable of independently and effectively controlling both VIS and NIR light. Here, we present Prussian blue (PB) with remarkable performance to replace the composite DBEMs that require deliberate design and complicated preparation. Excellent durability and capacity were achieved simultaneously due to the activated low-spin Fe in PB. A dual-band electrochromic device (DBED) by using PB thin films as electrochromic layers was constructed, exhibiting superior dual-band electrochromic performance, energy storage performance and memory effect. We show that the energy-saving DBED can be bleached without applying any external bias potential, and can be colored by using a commercial photovoltaic solar panel under ambient solar irradiation. The stored energy during coloration can be further used to light up the lights. Finally, the coloration mechanism of the DBED was studied by the density functional theory calculations, to shed light on the large optical transmittance modulation in both VIS and NIR regions. The new insights will advance the design of efficient and durable DBEMs and the development of bi-functional smart windows.

6.
Neuroreport ; 31(9): 678-685, 2020 06 07.
Artigo em Inglês | MEDLINE | ID: mdl-32427713

RESUMO

Major depressive disorder (MDD) is a highly prevalent debilitating psychiatric disease and a serious public health problem worldwide. Brain structural MRI and postmortem studies on patients with depression have revealed changes in the anatomy and functionality in various brain regions, including the amygdala, thalamus, hippocampus, and prefrontal cortex (PFC). The alterations in these brain regions could be a result, in part, of the dysregulation of the neurotrophic factors. Neuregulin1 (NRG1) is one of the neurotrophic factors, and our previous study showed that the NRG1-ErbB4 signaling pathway plays a critical role in epilepsy. In this study, we established a chronic social defeat stress (CSDS) model to investigate the role of the NRG1-ErbB4 signaling pathway in depression-like behaviors. In CSDS mice, we found that the NRG1 protein expression levels were significantly decreased both in the medial prefrontal cortex (mPFC) and hippocampus, while phosphorylated ErbB4 only decreased in the mPFC. In addition, lateral ventricle NRG1 administration significantly rescued depression-like behaviors in the susceptible group. The current study suggests that the NRG1-ErbB4 signaling pathway may exert a protective role in MDD.


Assuntos
Depressão/metabolismo , Hipocampo/metabolismo , Neuregulina-1/metabolismo , Córtex Pré-Frontal/metabolismo , Receptor ErbB-4/metabolismo , Derrota Social , Estresse Psicológico/metabolismo , Animais , Depressão/complicações , Masculino , Camundongos Endogâmicos C57BL , Transdução de Sinais , Estresse Psicológico/complicações
7.
J Mater Chem A Mater ; 7(6): 2908-2918, 2019 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-30931123

RESUMO

Electrochromic windows and glass facades are able to impart energy efficiency jointly with indoor comfort and convenience. Long-term durability is essential for practical implementation of this technology and has recently attracted broad interest. Here we show that a simple potentiostatic pretreatment of sputter-deposited thin films of amorphous WO3-the most widely studied electrochromic material-can yield unprecedented durability for charge exchange and optical modulation under harsh electrochemical cycling in a Li-ion-conducting electrolyte and effectively evades harmful trapping of Li. The pretreatment consisted of applying a voltage of 6.0 V vs. Li/Li+ for several hours to a film backed by a transparent conducting In2O3:Sn layer. Associated compositional and structural modifications were probed by several techniques, and improved durability was associated with elemental intermixing at the WO3/ITO and ITO/glass boundaries as well as with carbonaceous solid-electrolyte interfacial layers on the WO3 films. Our work provides important new insights into long-term durability of ion-exchange-based devices.

8.
ACS Appl Mater Interfaces ; 9(49): 42420-42424, 2017 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-29164852

RESUMO

Nickel oxide thin films are of major importance as anodically coloring components in electrochromic smart windows with applications in energy-efficient buildings. However, the optical performance of these films degrades upon extended electrochemical cycling, which has hampered their implementation. Here, we use a potentiostatic treatment to rejuvenate degraded nickel oxide thin films immersed in electrolytes of LiClO4 in propylene carbonate. Time-of-flight elastic recoil detection analysis provided unambiguous evidence that both Li+ ions and chlorine-based ions participate in the rejuvenation process. Our work provides new perspectives for developing ion-exchange-based devices embodying nickel oxide.

9.
Chem Asian J ; 12(22): 2922-2928, 2017 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-28881092

RESUMO

For the first time, a crystalline-amorphous double-layered NiOx film has been prepared by reactive radio frequency magnetron sputtering. This film has exhibited improved electrochemical cycling durability, whereas other electrochromic parameters have been maintained at the required level, namely, a short coloration/bleaching time (0.8 s/1.1 s) and an enhanced transmittance modulation range (62.2 %) at λ=550 nm. Additionally, the double-layered film has shown better reversibility than that of amorphous and crystalline single-layered films.

10.
Chem Asian J ; 11(20): 2882-2888, 2016 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-27459370

RESUMO

In this paper, three-dimensionally ordered macroporous (3DOM) poly(3,4-ethylenedioxythiophene) (PEDOT) films were electropolymerized from an ionic liquid, 1-butyl-3-methylimidazolium hexafluorophosphate ([Bmim]PF6 ). The electrochromic performances of the 3DOM PEDOT films were studied. The 3DOM films exhibited high transmittance modulation (41.2 % at λ=580 nm), high ionic fast switching speeds (0.7 and 0.7 s for coloration and bleaching, respectively), and enhanced cycling stability relative to that exhibited by the dense PEDOT film. The relationship between the declining behavior of the transmittance modulation and the nanostructure of the film was investigated. A three-period decay process was proposed to understand the declining behavior. The 3D interconnected macroporous nanostructure is beneficial for fast ion and electron transportation, high ion accessibility, and maintenance of structure integrity, which result in enhanced cycling stability and fast switching speeds.

11.
Analyst ; 128(5): 462-6, 2003 May.
Artigo em Inglês | MEDLINE | ID: mdl-12790198

RESUMO

Nanometer-sized fluorescent hybrid silica (NFHS) particles were prepared for use as sensitive and photostable fluorescent probes in biological staining and diagnostics. The first step of the synthesis involves the covalent modification of 3-aminopropyltrimethoxysilane with an organic fluorophore, such as fluorescein isothiocyanate, under N2 atmosphere for getting a fluorescent silica precursor. Then the NFHS particles, with a diameter of well below 40 nm, were prepared by controlled hydrolysis of the fluorescent silica precursor with tetramethoxysilane (TMOS) using the reverse micelle technique. The fluorophores are dispersed homogeneously in the silica network of the NFHS particles and well protected from the environmental oxygen. Furthermore, since the fluorophores are covalently bound to the silica network, there is no migration, aggregation and leakage of the fluorophores. In comparison with common single organic fluorophores, these particle probes are brighter, more stable against photobleaching and do not suffer from intermittent on/off light emission (blinking). We have used these newly developed NFHS particles as a fluorescent marker to label antibodies, using silica immobilization method, for the immunoassay of human alpha-fetoprotein (AFP). The detection limit of this method was down to 0.05 ng mL(-1) under our current experimental conditions. We think this material would attract much attention and be applied widely in biotechnology.

12.
Anal Biochem ; 308(1): 71-6, 2002 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-12234465

RESUMO

Sol-gel-derived mesoporous biomaterials were used for the first time in the flow-injection fluorescence immunoassay system. Anti-gentamicin antibody was immobilized in a mesoporous sol-gel material using tetramethoxysilane as a precursor and poly(ethylene glycol) as a template. The sol-gel glass was used to develop an immunoaffinity column for the flow-injection immunoassay of gentamicin. Little unspecific adsorption of gentamicin on the sol-gel and no antibody leaching under harsh elution conditions were found. The immunoassay is based on the competition between gentamicin and fluorescein isothiocyanate-labeled gentamicin for a limited number of encapsulated antibody binding sites. NaOH solution of 5 x 10(-3)mol/L is used for the regeneration of encapsulated antibody binding sites after each measurement, which allows the immunoreactor to be used for up to 20 times without any loss of reactivity. Sample preconcentration is not needed and a single assay can be performed within 10 min. The calibration for gentamicin has a working range of 250-5000 ng/mL with a detection limit of 200 ng/mL, which is close to that of the fluorescence immunoassay and fluorescence polarization immunoassay using the same reactants. Comparison of the results from this method with that obtained from HPLC showed an excellent correlation.


Assuntos
Materiais Biocompatíveis/química , Análise de Injeção de Fluxo/métodos , Imunoensaio de Fluorescência por Polarização/métodos , Gentamicinas/sangue , Adsorção , Anticorpos Monoclonais/química , Anticorpos Monoclonais/metabolismo , Ligação Competitiva , Calibragem , Cromatografia Líquida de Alta Pressão , Análise de Injeção de Fluxo/instrumentação , Fluoresceína-5-Isotiocianato/química , Imunoensaio de Fluorescência por Polarização/instrumentação , Géis , Gentamicinas/análise , Humanos , Polietilenoglicóis/química , Porosidade , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Estatística como Assunto
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