- 标题
- 摘要
- 关键词
- 实验方案
- 产品
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One-step Aqueous Synthesis of Zn-based Quantum Dots as Potential Generators of Reactive Oxygen Species
摘要： The actual incorporation of dopant species into the ZnS Quantum Dots (QDs) host lattice will induce structural defects evidenced by a red shift in the corresponding exciton. The doping should create new intermediate energetic levels between the valence and conduction bands of the ZnS and affect the electron-hole recombination. These trap states would favour the energy transfer processes involved with the generation of cytotoxic radicals, so-called Reactive Oxygen Species, opening the possibility to apply these nanomaterials in cancer research. Any synthesis approach should consider the direct formation of the QDs in biocompatible medium. Accordingly, the present work addresses the microwave-assisted aqueous synthesis of pure and doped ZnS QDs. As-synthesized quantum dots were fully characterized on a structural, morphological and optical viewpoint. UV-Vis analyzes evidenced the excitonic peaks at approximately 310 nm, 314 nm and 315 nm for ZnS, Cu-ZnS and Mn-ZnS, respectively, Cu/Zn and Mn/Zn molar ratio was 0.05%. This indicates the actual incorporation of the dopant species into the host lattice. In addition, the Photoluminescence spectrum of non-doped ZnS nanoparticles showed a high emission peak that was red shifted when Mn2+ or Cu2+ were added during the synthesis process. The main emission peak of non-doped ZnS, Cu-doped ZnS and Mn-doped ZnS were observed at 438 nm, 487 nm and 521 nm, respectively. Forthcoming work will address the capacity of pure and Cu-, Mn-ZnS quantum dots to generate cytotoxic Reactive Oxygen Species for cancer treatment applications.
关键词： Cancer research,ZnS Quantum Dots,Doping,Microwave-assisted synthesis,Reactive Oxygen Species
更新于2025-11-19 16:46:39
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Métodos para a tomada de decis?o em portfólio de produtos: um levantamento em empresas dos setores eletr?nico, óptico e de informática
摘要： Decision making in product portfolio is a relevant aspect, not only to the good performance of product development, but also to support in the process of business strategy. This article has the objective to present and analyze the main methods for decision making in product portfolio used by large and medium enterprises that operate in Brazil, in electronic, optical and computer sectors. A survey research was conducted in a sample of 40 companies. It was noted, that most of these companies, especially the middle sized companies, followed an informal pattern for decision-making in product portfolio, which is guided, mainly, by the perception of senior management. Among the employed formal methods, financial, market research and mapping methods are the most present in the surveyed sectors.
关键词： Process of Product Development,Survey research,Methods for Decision Making,Product Portfolio Management,Electronic, optical and computing companies
更新于2025-09-23 15:23:52
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Reporting of light irradiation conditions in 300 laboratory studies of resin-composites
摘要： Objective. To evaluate how the light delivered to resin-composites was described in recent articles. Method. PubMed was searched for 300 articles published between January 2017 and May 2018 with keywords relating to photocuring of dental materials. The articles examined a wide range of resin-composite properties and performance. For each article, the information provided about the light curing unit (LCU), the light curing conditions and the characteristics and quantity of the light used in the study were recorded. Specifically, the type of LCU used; the irradiance; how the irradiance was measured; the exposure times; whether the light energy (radiant exposure) received by the specimen was determined, or if only the light output at the LCU tip was measured; whether the distance between the tip of the LCU and the specimen was reported; and whether the emission spectrum from the LCU was reported. Where possible, the resin manufacturer’s minimum energy requirement (MER: the product of the recommended minimum exposure time and irradiance) was compared to the radiant exposure delivered to the specimen. Results. Of the 300 articles examined, 217 were published in 2017 and 83 in 2018. Of these articles, 130 (43%) were found in open access journals, and 170 (57%) were in subscription-based journals. The name of the LCU used was not provided in 31 articles, 14 articles did not provide the exposure time, and 227 articles did not report the distance to the specimen. An irradiance value was reported in 231 articles, but this was the irradiance received by the specimen in only 48 instances. The emission spectrum from the LCU was reported in 15 articles. There was a large range in the radiant exposures from below 10 J/cm2 to greater than 100 J/cm2. Significance. The majority of articles from 2017 and early 2018 did not include sufficient description of the characteristics and quantity of the light received by the resin-composite specimens to allow the study to be replicated. It is recommended that future articles should report: (1) the identity of the LCU used; (2) the radiant exposure received by the specimen (J/cm2); and (3) appropriate reference to the emission spectrum from the LCU.
关键词： Research reproducibility and replicability,Bond strength,Resins,Light curing,Bulk fill,Light measurement
更新于2025-09-23 15:23:52
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[IEEE 2018 International Multi-Conference on Industrial Engineering and Modern Technologies (FarEastCon) - Vladivostok, Russia (2018.10.3-2018.10.4)] 2018 International Multi-Conference on Industrial Engineering and Modern Technologies (FarEastCon) - Quality Control of Sodium High-Pressure Lamps by the Singular Decomposition Method
摘要： We created a mathematical model of a sodium high-pressure lamp. This model is used in production before sending lamps to the consumer. To develop the model, we used a mathematical model. An analytical method was used to describe the operation of a sodium lamp based on differential equations. We also used the singular value decomposition algorithm to find the coefficients of the ARMA model. Also, the transfer function of the ARMA model was obtained. Then we tested the models to control the quality of sodium lamps in production. The obtained results of the simulation coincide with the experimental results. A graphical dependence is obtained in the case when the standard deviation is 1. Using a series of tests based on the singular value decomposition method, we confirmed the adequacy of elaborated model by Kolmogorov-Smirnov criterion.
关键词： experimental research,mathematical model,sodium lamp
更新于2025-09-23 15:23:52
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Technology evolution and long waves: investigating their relation with spectral and cross-spectral analysis
摘要： The present paper is an empirical exercise that contributes to the debate on whether long-lasting cyclical economic development can be viewed as a deterministic phenomenon or a stochastic process. First, we search for longer lasting, periodically reappearing cycles of GDP per capita in four countries: USA, UK, Germany and France. Second, based on theoretical arguments that stress applied knowledge as a significant driving force, we test its dynamic interrelationship with these countries’ economic performance by applying spectral and cross-spectral methodologies. We confirm the existence of periodical long waves both in terms of GDP per capita as well as of applied knowledge. Moreover, we find strong interrelations between them and modest evidence for which is the leading force in the long term.
关键词： applied research,cross-spectral analysis,Long waves
更新于2025-09-23 15:22:29
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[IEEE 2018 IV International Conference on Information Technologies in Engineering Education (Inforino) - Moscow, Russia (2018.10.23-2018.10.26)] 2018 IV International Conference on Information Technologies in Engineering Education (Inforino) - Application of MatLab for Solid Surface Analysis by Means of X-Ray Photoelectron Spectroscopy
摘要： Efficiency of using the MatLab package to solve the problems of analysis of solid by means of X-ray photoelectron spectroscopy. A high-level programming language, fast matrix libraries MatLab, Signal Processing Toolbox and Curve Fitting Toolbox enabled to use more complicated, physically grounded calculation models for chemical and phase depth profiling of solid and calculate thicknesses of sub-surface layers with a sub-monolayer accuracy. The approach is used in educational and scientific students’ research.
关键词： chemical and phase depth profiling,XPS,MatLab,students’ research
更新于2025-09-23 15:22:29
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State-of-the-art: functional fluorescent probes for bioimaging and pharmacological research
摘要： Cardiovascular diseases, neuropsychiatric disorders, and cancers seriously endanger human health. Mechanistic and pharmacological mechanisms of candidate drugs are central to the translational paradigm. Since many signal transduction and molecular events are implicated in these diseases, a novel method to interrogate the key pharmacological mechanisms is required to accelerate innovative drug discovery. Much attention now focuses on the real-time visualization of molecular disease events to yield new insights to the pathogenesis of the diseases. This review focuses on recent advances in the development of chemical probes for imaging pathological events to facilitate the study of the underlying pharmacodynamics and toxicity involved. As reviewed here, optical imaging is now frequently viewed as an indispensable technique in the field of biological research. Promoting interdisciplinary collaboration among chemistry, biology and medicine, is necessary to further refine functional fluorescent probes for diagnostic and therapeutic applications.
关键词： pharmacological research,fluorescent probes,chemical biology,optical imaging,bioimaging
更新于2025-09-23 15:21:21
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[IEEE 2018 VII. Lighting Conference of the Visegrad Countries (Lumen V4) - Trebic, Czech Republic (2018.9.18-2018.9.20)] 2018 VII. Lighting Conference of the Visegrad Countries (Lumen V4) - Directions of Research and Standardization in the Field of Outdoor Lighting
摘要： This paper aims to highlight current trends in research and standardization in light and lighting with focus on the outdoor lighting. Activities of the International Commission on Illumination (CIE) are briefly presented and detailed in selected topics picked up from the list of research priorities. The highlighted topics comprise adaptive lighting, tailored lighting, new lighting metrics, maintenance factor and obtrusive light issues in particular. Outlook for standardization items, priorities and strategy is outlined in the paper.
关键词： obtrusive light,smart lighting,research,outdoor lighting,maintenance factor,standardization,tailored lighting,light and lighting,adaptive lighting
更新于2025-09-23 15:21:21
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[IEEE 2018 International Conference on Information and Telecommunication Technologies and Radio Electronics (UkrMiCo) - Odessa, Ukraine (2018.9.10-2018.9.14)] 2018 International Conference on Information and Telecommunication Technologies and Radio Electronics (UkrMiCo) - Spatial-Energy Characteristics of Focused Modes of Metallic Terahertz Laser Resonator
摘要： Cellular networks are currently experiencing a tremendous growth of data traffic. To cope with this demand, a close cooperation between academic researchers and industry/standardization experts is necessary, which hardly exists in practice. In this paper, we try to bridge this gap between researchers and engineers by providing a review of current standard-related research efforts in wireless communication systems. Furthermore, we give an overview about our attempt in facilitating the exchange of information and results between researchers and engineers, via a common simulation platform for 3GPP long term evolution (LTE) and a corresponding webforum for discussion. Often, especially in signal processing, reproducing results of other researcher is a tedious task, because assumptions and parameters are not clearly specified, which hamper the consideration of the state-of-the-art research in the standardization process. Also, practical constraints, impairments imposed by technological restrictions and well-known physical phenomena, e.g., signaling overhead, synchronization issues, channel fading, are often disregarded by researchers, because of simplicity and mathematical tractability. Hence, evaluating the relevance of research results under practical conditions is often difficult. To circumvent these problems, we developed a standard-compliant open-source simulation platform for LTE that enables reproducible research in a well-defined environment. We demonstrate that innovative research under the confined framework of a real-world standard is possible, sometimes even encouraged. With examples of our research work, we investigate on the potential of several important research areas under typical practical conditions, and highlight consistencies as well as differences between theory and practice.
关键词： MIMO,pilot power allocation,LTE,Heterogeneous networks,distributed antenna systems,reproducible research,frequency synchronization,multiuser gains
更新于2025-09-23 15:21:01
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[IEEE 2019 15th International Conference on Signal-Image Technology & Internet-Based Systems (SITIS) - Sorrento, Italy (2019.11.26-2019.11.29)] 2019 15th International Conference on Signal-Image Technology & Internet-Based Systems (SITIS) - Assessment of OLED Head Mounted Display for Vision Research with Virtual Reality
摘要： Vision researchers often rely on visual display technology to present observers with controlled stimuli, usually by means of a calibrated computer screen. Virtual Reality (VR) may allow a similar level of control, together with higher realism of the stimulation and a visual field larger than what is achievable on a standard computer monitor. To produce the desired the stimuli, accurate characterization of the spectral properties of the display is necessary. However, this process might not be trivial on VR displays, because 1) the Head Mounted Displays (HMD) used in VR are typically designed to be light-weight and low energy consuming, thus they might not meet some of the standard assumptions in display calibration, 2) the VR software might affect the color and luminance signal in a complex way, further complicating the calibration process. Here we show that 1) a common, off-the-shelf display used in our experiments behaves similarly to a standard OLED monitor, 2) the VR gaming engine we tested (Unreal Engine 4) introduces a complex behavior, 3) which can be disabled. This allows to accurately control colors and luminance emitted by the display, thus enabling its use for perceptual experiments.
关键词： Head Mounted Display,Color Calibration,Vision Research,Virtual Reality,OLED
更新于2025-09-23 15:21:01