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Game playing is an accessible leisure activity. Recently, the World Health Organization officially included gaming disorder in the ICD-11, and studies using several bio-signals were conducted to quantitatively determine this. However, most EEG studies regarding internet gaming disorder (IGD) were conducted in the resting state, and the outcomes appeared to be too inconsistent to identify a general trend. Therefore, this study aimed to use a series of statistical processes with all the existing EEG parameters until the most effective ones to identify the difference between IGD subjects IGD and healthy subjects was determined. Thirty subjects were grouped into IGD (n = 15) and healthy (n = 15) subjects by using the Young's internet addition test (IAT) and the compulsive internet use scale (CIUS). EEG data for 16 channels were collected while the subjects played League of Legends. For the exhaustive search of parameters, 240 parameters were tested in terms of t-test, factor analysis, Pearson correlation, and finally logistic regression analysis. After a series of statistical processes, the parameters from Alpha, sensory motor rhythm (SMR), and MidBeta ranging from the Fp1, C3, C4, and O1 channels were found to be best indicators of IGD symptoms. The accuracy of diagnosis was computed as 63.5-73.1% before cross-validation. The most interesting finding of the study was the dynamics of EEG relative power in the 10-20 Hz band. This EEG crossing phenomenon between IGD and healthy subjects may explain why previous research showed inconsistent outcomes. The outcome of this study could be the referential guide for further investigation to quantitatively assess IGD symptoms.
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Comportamento Aditivo , Jogos de Vídeo , Humanos , Transtorno de Adição à Internet , Comportamento Aditivo/diagnóstico , Eletroencefalografia , Análise Fatorial , InternetRESUMO
The purpose of this study is to determine heart rate variability (HRV) parameters that can quantitatively characterize game addiction by using electrocardiograms (ECGs). 23 subjects were classified into two groups prior to the experiment, 11 game-addicted subjects, and 12 non-addicted subjects, using questionnaires (CIUS and IAT). Various HRV parameters were tested to identify the addicted subject. The subjects played the League of Legends game for 30-40 min. The experimenter measured ECG during the game at various window sizes and specific events. Moreover, correlation and factor analyses were used to find the most effective parameters. A logistic regression equation was formed to calculate the accuracy in diagnosing addicted and non-addicted subjects. The most accurate set of parameters was found to be pNNI20, RMSSD, and LF in the 30 s after the "being killed" event. The logistic regression analysis provided an accuracy of 69.3% to 70.3%. AUC values in this study ranged from 0.654 to 0.677. This study can be noted as an exploratory step in the quantification of game addiction based on the stress response that could be used as an objective diagnostic method in the future.
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Comportamento Aditivo , Jogos de Vídeo , Comportamento Aditivo/diagnóstico , Eletrocardiografia , Frequência Cardíaca , Humanos , Inquéritos e QuestionáriosRESUMO
Deoxyribonucleic acid (DNA) and a self-doped conjugated polyelectrolyte, poly(4-(2,3-dihydrothieno[3,4-b]-[1,4]dioxin-2-yl-methoxy)-1-butanesulfonic acid (PEDOT-S), are assembled for organic optoelectronics and bioelectronics. The DNA's helix-coil phase transition in water is studied as a function of composition by thermo-optical analysis. DNA and PEDOT-S are functionalized by using a surfactant, cetyltrimethylammonium chloride (CTMA), and DNA:CTMA, PEDOT-S:CTMA, and DNA:CTMA:PEDOT-S:CTMA complexes were characterized regarding thermal, optical, morphological, and structural properties. Finally, DNA and DNA:PEDOT-S mixtures are processed in water for fabricating organized films through brushing. The electrical properties of these films are characterized using an interdigitated electrode. The films show an electronic conductivity of â¼10-6-10-5 S/cm in a range of semiconductors.
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DNA , Polímeros , Cetrimônio , Condutividade Elétrica , PolieletrólitosRESUMO
Although the introduction of human epidermal growth factor receptor (HER)2-directed therapy including trastuzumab, pertuzumab, lapatinib and trastuzumab emtansine (T-DM1) in the treatment of HER2-positive metastatic breast cancers (mBCs) favorably changed the natural history of this disease, most cases of HER2-positive mBC will eventually progress. Poziotinib is an oral pan-HER kinase inhibitor showing potent activity through irreversible inhibition of these kinases. This open-label, multicenter phase II study was designed to evaluate the efficacy and safety of poziotinib monotherapy in patients with HER2-positive mBC who had progressed from more than two HER2-directed therapies. Patients received 12 mg poziotinib once daily on a 14-day on/7-day off schedule. Progression-free survival (PFS) as the primary endpoint, the objective response rate (ORR), overall survival (OS) and safety were evaluated. From April 2015 to February 2016, 106 patients were enrolled in the trial from seven institutes in South Korea. They had a median age of 51 years (range 30-76) and had received a median of four prior therapies including two HER2-directed therapies for advanced or metastatic cancers. The median follow-up duration was 12 months. The median PFS was 4.04 months (95% confidence interval [CI], 2.94-4.40 months), and median overall survival has not been reached. The most common treatment-related adverse events were (total/grade ≥3) diarrhea (96.23%/14.15%), stomatitis (92.45%/12.26%) and rashes (63.21%/3.77%). Poziotinib showed meaningful activity in these heavily treated HER2-positive mBCs. Diarrhea and stomatitis were the major toxicities. Biomarker studies analyzed are warranted to support further evaluation of this treatment in such cases.
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Antineoplásicos/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Inibidores de Proteínas Quinases/uso terapêutico , Quinazolinas/uso terapêutico , Receptor ErbB-2/metabolismo , Adulto , Idoso , Antineoplásicos/efeitos adversos , Neoplasias da Mama/metabolismo , Intervalo Livre de Doença , Feminino , Humanos , Pessoa de Meia-Idade , Metástase Neoplásica , Inibidores de Proteínas Quinases/efeitos adversos , Quinazolinas/efeitos adversos , Receptor ErbB-2/antagonistas & inibidores , Recidiva , República da Coreia , Análise de SobrevidaRESUMO
IMPORTANCE: Corneal refractive surgery may impact meibomian gland and tear film in post-refractive surgery patients. BACKGROUND: To compare ocular surface parameters between post-refractive surgery patients and normal controls. DESIGN: Cross-sectional single centre study. PARTICIPANTS: A total of 120 eyes of 120 subjects were divided into three groups: (i) 60 controls and 60 patients underwent corneal refractive surgery at least 12 months ago; (ii) 30 post-laser in-situ keratomileusis (LASIK) patients and (iii) 30 post-laser epithelial keratomileusis (LASEK)/photo-refractive keratectomy (PRK) patients. METHODS: Tear meniscus height, non-invasive keratographic tear film break-up time and meibography were measured using the Keratograph® 5M. Fluorescein break-up time, ocular surface staining, examination of lid margins and meibomian glands, Schirmer's test and Ocular Surface Disease Index questionnaire were performed. MAIN OUTCOME MEASURES: Ordinary logistic regression was performed to evaluate the impact of clinical variables including refractive surgery on the meiboscores. RESULTS: In post-LASIK patients, ocular surface parameters including Ocular Surface Disease Index scores, fluorescein break-up time and staining scores, except Schirmer's scores, were significantly worse than those in controls (P < 0.050). Ocular surface staining scores in post-LASEK/PRK patients was higher than that in the controls (P = 0.001). In post-refractive surgery patients, grade of meibomian gland parameters and meiboscores were worse than those of controls (all P < 0.050). Histories of refractive surgery were associated with high meiboscore (ß = 1.100, P = 0.043 for LASIK and ß = 1.039, P = 0.042 for LASEK/PRK). CONCLUSIONS AND RELEVANCE: Corneal refractive surgery may adversely affect the ocular surface, and a reduction of functional meibomian glands can contribute to chronic tear film dysfunction after corneal refractive surgery.
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Glândulas Tarsais/metabolismo , Procedimentos Cirúrgicos Refrativos , Lágrimas/química , Adulto , Feminino , Humanos , Masculino , Glândulas Tarsais/diagnóstico por imagem , Período Pós-Operatório , Estudos Retrospectivos , Adulto JovemRESUMO
Considering the many emerging markets in East Asia, access to contemporary anthropometric data for this region is important for designers and manufacturers seeking to produce the best fitting products and living environments for consumers. The purpose of this paper is to describe Korean anthropometric data collection and survey techniques for those who are interested in ethnic characteristics, conducting surveys, and formulating ergonomic product designs for South Korean and, more broadly, East Asian populations. The Size Korea survey was conducted in 2003-2004 and 2010. A total of 14,200 civilians aged 0-90 years participated in the survey, with 119 body and weight dimensions measured in 2004. Twenty new dimensions from Inbody measurement were added in 2010 and the data were continuously updated. We referred to ISO 7250, 8559 and 15535 to ensure validity and reliability. Fifty major body dimensions, including weight, are summarised in this paper, and 34 of these dimensions can be compared with 11 multinational data already reported in other publications. Practitioner Summary: This paper presents the up-to-date anthropometric database of East Asian physical characteristics and survey methodology. These data satisfy the ISO standards and comprise 50 physical dimensions including weight. Thirty-four dimensions of these can be directly compared with available multinational data.
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Povo Asiático , Pesos e Medidas Corporais , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Antropometria , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , República da Coreia , Adulto JovemRESUMO
This laboratory study evaluated the effect of glare source (halogen, HID and LED) and its illumination levels (0.7, 2 and 5 lx) using a quantitative methodology. Pupil diameter and electroencephalography were measured using FaceLab and Biopac systems, respectively. The discomfort glare was assessed subjectively with Borg's CR-10 scale. Twenty healthy subjects participated. Pupil size was significantly affected by the headlamp type and illumination condition. Pupil size was smaller when exposed to the LED headlamp than other headlamps (Halogen > HID > LED). In addition, when the illumination increased, pupil size decreased (0.7 lx > 2 lx > 5 lx). Also, driver's discomfort increased when pupil size was small, and theta waves were high. This discomfort may cause reduced attention and safety of the driver. These results can be applied to design and development of headlamps. Further investigation is necessary with adopted methodology to evaluate other headlamps in different illumination conditions. Practitioner Summary: This study evaluated pupil size and electroencephalography under different glare source (halogen, HID and LED) and illumination levels (0.7, 2 and 5 lx). Driver's discomfort increased when pupil size was small, and theta waves were high. This discomfort may cause reduced attention and safety of the driver.
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Condução de Veículo , Ofuscação , Luz , Iluminação , Pupila/fisiologia , Adulto , Automóveis , Eletroencefalografia , Humanos , Masculino , Reflexo PupilarRESUMO
The aim of the study was to evaluate the difference in legibility between e-books and paper books by using an eye tracker. Eight male and eight female subjects free of eye disease participated in the experiment. The experiment was conducted using a 2 × 3 within-subject design. The book type (e-book, paper book) and font size (8 pt, 10 pt, 12 pt) were independent variables, and fixation duration time, saccade length, blink rate and subjective discomfort were dependent variables. In the results, all dependent variables showed that reading paper books provided a better experience than reading e-books did. These results indicate that the legibility of e-books needs further improvement, considering fixation duration time, saccade movement, eye fatigue, device and so on. PRACTITIONER SUMMARY: This study evaluated the legibility difference between e-books and paper books from the viewpoint of readability, eye fatigue and subjective discomfort by using an eye tracker. The results showed that paper books provided a better experience than e-books. This indicates that the readability of e-books needs further improvement in relation to paper books.
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Livros , Leitura , Adulto , Equipamentos e Provisões Elétricas , Medições dos Movimentos Oculares/instrumentação , Movimentos Oculares/fisiologia , Feminino , Humanos , Masculino , Adulto JovemRESUMO
The goal of this study was to quantify the effect of experience and handrail presence on trunk muscle activities, rotational spinal stiffness and postural stability of construction workers. We evaluated spinal stability, and objective and subjective postural stability in 4 expert and 4 novice construction workers who were performing a manual task in a standing position on a scaffold, with and without a safety handrail. Center of pressure was computed using measurements taken with insole pressure transducers. Muscle activity was monitored using surface electrodes placed on 8 trunk muscles that predicted active trunk rotational stiffness. Standard deviations of the center of pressure, back muscle activity and spinal stiffness were greater in novices and in the absence of a handrail. We infer that the risk of a fall due to postural and spinal instability may be greater with a lower level of experience and in the absence of a safety handrail.
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Indústria da Construção , Equilíbrio Postural/fisiologia , Equipamentos de Proteção , Coluna Vertebral/fisiologia , Adulto , Fenômenos Biomecânicos , Eletromiografia , Humanos , Masculino , Músculo Esquelético/fisiologia , Saúde Ocupacional , Amplitude de Movimento Articular/fisiologia , Gestão da SegurançaRESUMO
Over more than a decade, lead halide perovskites (LHPs) have been popular as a next-generation semiconductor for optoelectronics. Later, all-inorganic CsPbX3 (X = Cl, Br, and I) nanocrystals (NCs) were synthesized via supersaturated recrystallization (SR) at room temperature (RT). However, compared to the hot injection (HI) method, the formation mechanism of NCs via SR-RT has not been well studied. Hence, this study will contribute to elucidating SR-RT based on the LaMer model and Hansen solubility parameter. Herein, we also demonstrate the entropy-driven mixing between two dissimilar polar-nonpolar (DMF-toluene) solvents. Next, we find that, in a poor solvent (toluene â« DMF in volume), â¼60 nm sized CsPbBr3 NCs were synthesized in one step, whereas in a marginal solvent (toluene ≈ DMF), â¼3.5 nm sized NCs were synthesized in two steps, indicating the importance of solvent polarity, specifically the 'solubility parameter'. In addition, in the presence of a CuBr2 additive, high-quality cubic NCs (with â¼3.8 nm and â¼21.4 nm edge sizes) were synthesized. Hence, through this study, we present a 'solubility parameter-based nanocrystal-size control model' for SR-RT processes.
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Room temperature (RT) synthesis of the ternary cesium lead bromide CsPbBr3 quantum dots with oleic acid and oleylamine ligands was developed by Zeng and coworkers in 2016. In their works, the supersaturated recrystallization (SR) was adopted as a processing method without requiring inert gas and high-temperature injection. However, the oleic acid ligand for haloplumbate is known to be relatively unstable. Hence, in this work, we employed the eco-friendly olive oil to replace the oleic acid portion for the SR process at RT. Resultantly, we found that the cube-shaped nanocrystal has a size of ~40-42 nm and an optical bandgap of ~2.3 eV independent of the surface ligands, but the photoluminescence lifetime (τav) and crystal packing are dependent on the ligand species, e.g., τav = 3.228 ns (olive oil and oleylamine; here less ordered) vs. 1.167 ns (oleic acid and oleylamine). Importantly, we explain the SR mechanism from the viewpoint of the classical LaMer model combined with the solvent engineering technique in details.
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The coronavirus (SARS-CoV-2) disease has affected the globe with 770 437 327 confirmed cases, including about 6 956 900 deaths, according to the World Health Organization (WHO) as of September 2023. Hence, it is imperative to develop diagnostic technologies, such as a rapid cost-effective SARS-CoV-2 detection method. A typical biosensor enables biomolecule detection with an appropriate transducer by generating a measurable signal from the sample. Graphene can be employed as a component for ultrasensitive and selective biosensors based on its physical, optical, and electrochemical properties. Herein, we briefly review graphene-based electrochemical, field-effect transistor (FET), and surface plasmon biosensors for detecting the SARS-CoV-2 target. In addition, details on the surface modification, immobilization, sensitivity and limit of detection (LOD) of all three sensors with regard to SARS-CoV-2 were reported. Finally, the point-of-care (POC) detection of SARS-CoV-2 using a portable smartphone and a wearable watch is a current topic of interest.
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Técnicas Biossensoriais , Grafite , Limite de Detecção , Sistemas Automatizados de Assistência Junto ao Leito , SARS-CoV-2 , SmartphoneRESUMO
In this study, carbon-free and completely soluble hydrogen peroxide (H2O2) was utilized in place of conventional surfactants as a pore-forming agent. Citric acid was also used in low concentration for the hydrolysis reaction. A sol-gel method was used to prepare bioactive glass (BG) specimens of H2O2-untreated BG, 1M, 2M, and 3M H2O2-treated BGs. X-ray diffraction (XRD), scanning electron microscopy (SEM), Fourier-transform infrared spectroscopy (FTIR), energy-dispersive spectroscopy (EDS), and nitrogen adsorption/desorption isotherm with the Brunauer-Emmett-Teller (BET) method were used for analyzing the samples' phase, surface morphology, chemical composition, constituent composition, pore size, and specific surface area respectively. In vitro bioactivity, as well as biodegradability tests, was performed on samples by immersing them in simulated body fluid (SBF) solution. According to the results, BG particles treated with 2 M H2O2 exhibited higher specific surface area (SSA), which is 189.55 cc/g, and better in vitro bioactivity and biodegradability.
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The phase change of all-inorganic cesium lead halide (CsPbI3) thin film from yellow δ-phase to black γ-/α-phase has been a topic of interest in the perovskite optoelectronics field. Here, the main focus is how to secure a black perovskite phase by avoiding a yellow one. In this work, we fabricated a self-doped CsPbI3 thin film by incorporating an excess cesium iodide (CsI) into the perovskite precursor solution. Then, we studied the effect of organic additive such as 1,8-diiodooctane (DIO), 1-chloronaphthalene (CN), and 1,8-octanedithiol (ODT) on the optical, structural, and morphological properties. Specifically, for elucidating the binary additive-solvent solution thermodynamics, we employed the Flory-Huggins theory based on the oligomer level of additives' molar mass. Resultantly, we found that the miscibility of additive-solvent displaying an upper critical solution temperature (UCST) behavior is in the sequence CN:DMF > ODT:DMF > DIO:DMF, the trends of which could be similarly applied to DMSO. Finally, the self-doping strategy with additive engineering should help fabricate a black γ-phase perovskite although the mixed phases of δ-CsPbI3, γ-CsPbI3, and Cs4PbI6 were observed under ambient conditions. However, the results may provide insight for the stability of metastable γ-phase CsPbI3 at room temperature.
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A simple wet chemical ultrasonic-assisted synthesis method was employed to prepare visible light-driven g-C3N4-ZnO-Co3O4 (GZC) heterojunction photocatalysts. X-ray diffraction (XRD), scanning electromicroscopy (SEM), Fourier-transform infrared spectroscopy (FTIR), Brunauer-Emmett-Teller (BET), ultraviolet (UV), and electrochemical impedance spectroscopy (EIS) are used to characterize the prepared catalysts. XRD confirms the homogenous phase formation of g-C3N4, ZnO, and Co3O4, and the heterogeneous phase for the composites. The synthesized ZnO and Co3O4 by using cellulose as a template show a rod-like morphology. The specific surface area of the catalytic samples increases due to the cellulose template. The measurements of the energy band gap of a g-C3N4-ZnO-Co3O4 composite showed red-shifted optical absorption to the visible range. The photoluminescence (PL) intensity decreases due to the formation of heterojunction. The PL quenching and EIS result shows that the reduction of the recombination rate and interfacial resistance result in charge carrier kinetic improvement in the catalyst. The photocatalytic performance in the degradation of MB dye of the GZC-3 composite was about 8.2-, 3.3-, and 2.5-fold more than that of the g-C3N4, g-C3N4-ZnO, and g-C3N4-Co3O4 samples. The Mott-Schottky plots of the flat band edge position of g-C3N4, ZnO, Co3O4, and Z-scheme g-C3N4-ZnO-Co3O4 photocatalysts may be created. Based on the stability experiment, GZC-3 shows greater photocatalytic activity after four recycling cycles. As a result, the GZC composite is environmentally friendly and efficient photocatalyst and has the potential to consider in the treatment of dye-contaminated wastewater.
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This study was performed to investigate the prevalence of musculoskeletal disorders in players of a variety of traditional Korean classical instruments: gayageum, geomungo, ajaeng, and haegeum. A large percentage of these musicians suffer from musculoskeletal pain of various body parts. However, there has been no research regarding the extent of musculoskeletal disorders in players of these instruments. Through a focus group interview, a questionnaire was developed to investigate musculoskeletal disorders. The questionnaire consisted of four parts: demographic factors, performance factors, musculoskeletal disorder symptoms, and musculoskeletal disorder experiences. Eighty-six expert players participated in this survey. The data from the survey were analyzed by correlation analysis and chi-squared analysis. Musculoskeletal disorders symptoms and severe pain were reported in the neck, shoulder, back and knee. These problems were statistically related to height for players of the gayageum and geomungo. In addition, the musculoskeletal disorder experience of geomungo players was correlated with age and career length. The symptoms of playing-related musculoskeletal disorders in traditional Korean music players were reported as being mostly observed in the neck, shoulder, back, and knee. In addition, these symptoms were related to various demographic factors such as age, height, career length, and hobby styles. The results of this study can be used as preliminary data for developing guidelines to prevent traditional Korean musical instrument players from developing musculoskeletal injuries.
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Doenças Musculoesqueléticas/epidemiologia , Música , Doenças Profissionais/epidemiologia , Exposição Ocupacional/estatística & dados numéricos , Postura , Adulto , Feminino , Grupos Focais , Humanos , Joelho/fisiopatologia , Masculino , Pessoa de Meia-Idade , Pescoço/fisiopatologia , Prevalência , República da Coreia/epidemiologia , Fatores de Risco , Extremidade Superior/fisiopatologia , Adulto JovemRESUMO
A fluoropolymer poly(vinylidene fluoride-co-hexafluoropropylene) (PVDF-HFP) has a dielectric constant of â¼11, providing charge screening effects. Hence, this highly polar PVDF-HFP material has been employed as a matrix for solid polymer electrolytes (SPEs). In this study, the phase behavior of binary PVDF-HFP solutions was analyzed using the Flory-Huggins theory, in which ethylene carbonate, propylene carbonate, dimethyl carbonate, γ-butyrolactone, and acetone were employed as model solvents. In particular, for the binary PVDF-HFP/acetone system, the solid-liquid and liquid-liquid phase transitions were qualitatively described. Then, the phase diagram for ternary acetone/PVDF-HFP/polyphenolate systems was constructed, in which the binodal, spinodal, tie-line, and critical point were included. Finally, when a polyelectrolyte lithium polyphenolate was mixed with the PVDF-HFP matrix, it formed a single-ion conductor with a Li+ transference number of 0.8 at 23 °C. In the case of ionic conductivity, it was â¼10-5 S cm-1 in solid state and â¼10-4 S cm-1 in gel state, respectively.
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Trivalent dysprosium/europium-codoped silicate phosphors (Ba1.3Ca0.7x-ySiO4:xDy3+/yEu3+) were prepared as a function of Eu3+concentration (x= 0.03 andy= 0.01-0.05). The phosphors showed the averaged crystallite size of â¼37.2 ± 1.3 nm and displayed nano-/micro-scale grains with some void defects. The energy bandgap is about 4.3 eV for co-doped samples and 3.2 eV for the silicate host. The photoluminescence spectra indicated that the presence of Eu3+ions enhanced the red light emission, and the emission peaks located at the versatile wavelengths of 482, 577, 592, 614, 652, and 703 nm. Then, the internal quantum efficiencies were estimated by using the Judd-Ofelt model. Resultantly, the best quantum efficiency was â¼74% when the doping concentrations were 3 mol% Dy3+and 4 mol% Eu3+ions. Finally, the CIE coordinate data exhibited that the emission color could be tuned from white to reddish-orange by changing the Eu3+contents, proposing the applicability of Ba1.3Ca0.7-x-ySiO4:xDy3+/yEu3+phosphors to the solid-state lighting.
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Phase diagrams of ternary π-bonded polymer (PTB7-Th) solutions were constructed as a function of molecular weight, temperature, and electron acceptor species (ITIC, PC61BM and PC71BM). For this purpose, the Flory-Huggins lattice theory was employed with a constant χ interaction parameter, describing a binodal, spinodal, tie line, and critical point. Then, the morphologies of the blends composed of highly disordered PTB7-Th and crystallizable ITIC were investigated by atomic force microscopy. Subsequently, the surface polarities of the PTB7-Th:ITIC thin films were examined by water contact-angle goniometer, exhibiting a transition at the composition of ~ 60 ± 10 wt.% ITIC. Furthermore, X-ray diffraction indicated the presence of ITIC's crystallites at ≥ 70 wt.% ITIC. Hence, the PTB7-Th:ITIC system was observed to undergo a phase transition at ~ 60-70 wt.% ITIC.
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The nano-biocomposite electrodes composed of carbon nanotube (CNT), polypyrrole (PPy), and E. coli-bacteria were investigated for electrochemical supercapacitors. For this purpose, PPy/CNT-E. coli was successfully synthesized through oxidative polymerization. The PPy/CNT-E. coli electrode exhibited a high specific capacitance of 173 Fâg-1 at the current density of 0.2 Aâg-1, which is much higher than that (37 Fâg-1) of CNT. Furthermore, it displayed sufficient stability after 1000 charge/discharge cycles. The CNT, PPy/CNT, and PPy/CNT-E. coli composites were characterized by x-ray diffraction, scanning electron microscopy, and surface analyzer (Brunauer-Emmett-Teller, BET). In particular, the pyrrole monomers were easily adsorbed and polymerized on the surface of CNT materials, as well as E. coli bacteria enhanced the surface area and porous structure of the PPy/CNT-E. coli composite electrode resulting in high performance of devices.