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Статті в журналах з теми "GQDs"
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Ku, Tien-Hsiung, Wen-Ting Shen, Chien-Te Hsieh, Grace Shiahuy Chen, and Wei-Chung Shia. "Specific Forms of Graphene Quantum Dots Induce Apoptosis and Cell Cycle Arrest in Breast Cancer Cells." International Journal of Molecular Sciences 24, no. 4 (February 17, 2023): 4046. http://dx.doi.org/10.3390/ijms24044046.
Повний текст джерелаАнотація:
Graphene quantum dots (GQDs), nanomaterials derived from graphene and carbon dots, are highly stable, soluble, and have exceptional optical properties. Further, they have low toxicity and are excellent vehicles for carrying drugs or fluorescein dyes. Specific forms of GQDs can induce apoptosis and could be used to treat cancers. In this study, three forms of GQDs (GQD (nitrogen:carbon = 1:3), ortho-GQD, and meta-GQD) were screened and tested for their potential to inhibit breast cancer cell (MCF-7, BT-474, MDA-MB-231, and T-47D) growth. All three GQDs decreased cell viability after 72 h of treatment and specifically affected breast cancer cell proliferation. An assay for the expression of apoptotic proteins revealed that p21 and p27 were up-regulated (1.41-fold and 4.75-fold) after treatment. In particular, ortho-GQD-treated cells showed G2/M phase arrest. The GQDs specifically induced apoptosis in estrogen receptor-positive breast cancer cell lines. These results indicate that these GQDs induce apoptosis and G2/M cell cycle arrest in specific breast cancer subtypes and could potentially be used for treating breast cancers.
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Zhang, Zheng, Yun Lei, Liyang Zhao, Zicong Jiang, and Zhong Ouyang. "Graphene Quantum Dots Decorated Al-doped ZnS for Improved Photoelectric Performance." Materials 11, no. 8 (August 16, 2018): 1452. http://dx.doi.org/10.3390/ma11081452.
Повний текст джерелаАнотація:
Graphene quantum dots (GQDs) decorated Al-doped ZnS composites were prepared using the solvothermal process, and the hydrothermal method was used to prepare GQDs. Various spectroscopic techniques were used to characterize the products, and the results show that Al-ZnS attached GQD composites present lattice fringes that can be assigned to ZnS and GQDs, respectively. The absorption peaks of Al-ZnS/GQDs are red-shifted because of the doping of aluminum and the incorporation of GQDs. The luminescence intensity of Al-ZnS/GQDs shows a downward trend with the addition of GQDs. As the GQD content changes from 0.6 wt % to 1.8 wt %, the photocurrent density achieves a maximum at the addition of 1.2 wt %. The photocurrent of Al-ZnS/GQDs composites are about 700% and 200% of pure ZnS and Al-ZnS, respectively. The results indicate that Al doping can reduce the energy bandgap of ZnS and produce more photogenerated electrons. The photogenerated electrons from Al-ZnS can be extracted and transferred to GQDs, which act as conducting materials to decrease the recombination rate and improve the photogenerated electron-transfer.
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Yim, Sang-Gu, Yong Kim, Ye-Eun Kang, Byung Moon, Eun Jung, and Seung Yang. "Size Fractionation of Fluorescent Graphene Quantum Dots Using a Cross-Flow Membrane Filtration System." Nanomaterials 8, no. 11 (November 21, 2018): 959. http://dx.doi.org/10.3390/nano8110959.
Повний текст джерелаАнотація:
Graphene quantum dots (GQDs) have received great attention as optical agents because of their low toxicity, stable photoluminescence (PL) in moderate pH solutions, and size-dependent optical properties. Although many synthetic routes have been proposed for producing GQD solutions, the broad size distribution in GQD solutions limits its use as an efficient optical agent. Here, we present a straightforward method for size fractionation of GQDs dispersed in water using a cross-flow filtration system and a track-etched membrane with cylindrical uniform nanopores. The GQD aqueous suspension, which primarily contained blue-emitting GQDs (B-GQDs) and green-emitting GQDs (G-GQDs), was introduced to the membrane in tangential flow and was fractionated with a constant permeate flow of about 800 L m−2 h−1 bar−1. After filtration, we observed a clear blue PL spectrum from the permeate side, which can be attributed to selective permeation of relatively small B-GQDs. The process provided a separation factor (B-GQDs/G-GQDs) of 0.74. In the cross-flow filtration system, size-dependent permeation through cylindrical nanochannels was confirmed by simulation. Our results demonstrate a feasible method facilitating size fractionation of two-dimensional nanostructures using a cross-flow membrane filtration system. Since membrane filtration is simple, cost-effective, and scalable, our approach can be applied to prepare a large amount of size-controlled GQDs required for high performance opto-electronics and bio-imaging applications.
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Golubewa, Lena, Tatsiana Kulahava, Aliona Klimovich, Danielis Rutkauskas, Ieva Matulaitiene, Renata Karpicz, Nikita Belko, et al. "Visualizing hypochlorous acid production by human neutrophils with fluorescent graphene quantum dots." Nanotechnology 33, no. 9 (December 9, 2021): 095101. http://dx.doi.org/10.1088/1361-6528/ac3ce4.
Повний текст джерелаАнотація:
Abstract In living organisms, redox reactions play a crucial role in the progression of disorders accompanied by the overproduction of reactive oxygen and reactive chlorine species, such as hydrogen peroxide and hypochlorous acid, respectively. We demonstrate that green fluorescence graphene quantum dots (GQDs) can be employed for revealing the presence of the hypochlorous acid in aqueous solutions and cellular systems. Hypochlorous acid modifies the oxygen-containing groups of the GQD, predominantly opens epoxide ring C–O–C, forms excessive C=O bonds and damages the carbonic core of GQDs. These changes, which depend on the concentration of the hypochlorous acid and exposure time, manifest themselves in the absorbance and fluorescence spectra of the GQD, and in the fluorescence lifetime. We also show that the GQD fluorescence is not affected by hydrogen peroxide. This finding makes GQDs a promising sensing agent for selective detecting reactive chlorine species produced by neutrophils. Neutrophils actively accumulate GQDs allowing to visualize cells and to examine the redox processes via GQDs fluorescence. At high concentrations GQDs induce neutrophil activation and myeloperoxidase release, leading to the disruption of GQD structure by the produced hypochlorous acid. This makes the GQDs a biodegradable material suitable for various biomedical applications.
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George, Deepak, Anirudh Suri, Khushboo Dutta, and Sunita Nayak. "Targeted Drug Delivery Using Graphene Quantum Dots: Approaches, Limitations and Future Perspectives." ECS Transactions 107, no. 1 (April 24, 2022): 16081–98. http://dx.doi.org/10.1149/10701.16081ecst.
Повний текст джерелаАнотація:
This mini-review centers on the framework of GQDs to function as a drug delivery system (DDS), that is both target-specific and efficient. Researchers exploit GQDs for the unique pharmacokinetic properties they possess, that make them an ideal multi-functional drug delivery vehicle. We cannot enhance the therapeutic efficacy of drugs merely by focusing on drug delivery mechanisms. The conjugation of the drug with GQD allows more flexibility in controlling the kinetics and circulation time of drug in the body, the characteristic which is highly regarded in modern therapeutics. GQDs possess properties such as enhanced water solubility, lower cytotoxicity, tunable photoluminescence properties, larger specific surface area, large surface to volume ratio, and ease of surface functionalization, which make them highly effective drug molecular loading cores. Also, the review addresses the various methods of synthesis of GQDs, that include top-down and bottom-up approaches; top-down modes being more feasible and advantageous. The review touches on the various modes of GQD drug-loaded delivery- release systems (DDRS). The review also addresses the limitations associated with drug delivery using GQDs. Insufficient information about the translocation of GQDs limits their application in biomedical field and make it difficult for GQD-based carriers to pass clinical trials. Through this review, we look to summarize the important concepts of drug delivery using GQDs, and their biomedical applications and scope in nanomedicine in foreseeable future
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Saud, Asif, Haleema Saleem, Nazmin Munira, Arqam Azad Shahab, Hammadur Rahman Siddiqui, and Syed Javaid Zaidi. "Sustainable Preparation of Graphene Quantum Dots for Metal Ion Sensing Application." Nanomaterials 13, no. 1 (December 28, 2022): 148. http://dx.doi.org/10.3390/nano13010148.
Повний текст джерелаАнотація:
Over the past several years, graphene quantum dots (GQDs) have been extensively studied in water treatment and sensing applications because of their exceptional structure-related properties, intrinsic inert carbon property, eco-friendly nature, etc. This work reported on the preparation of GQDs from the ethanolic extracts of eucalyptus tree leaves by a hydrothermal treatment technique. Different heat treatment times and temperatures were used during the hydrothermal treatment technique. The optical, morphological, and compositional analyses of the green-synthesized GQDs were carried out. It can be noted that the product yield of GQDs showed the maximum yield at a reaction temperature of 300 °C. Further, it was noted that at a treatment period of 480 min, the greatest product yield of about 44.34% was attained. The quantum yields of prepared GQDs obtained after 480 min of treatment at 300 °C (named as GQD/300) were noted to be 0.069. Moreover, the D/G ratio of GQD/300 was noted to be 0.532 and this suggested that the GQD/300 developed has a nano-crystalline graphite structure. The TEM images demonstrated the development of GQD/300 with sizes between 2.0 to 5.0 nm. Furthermore, it was noted that the GQD/300 can detect Fe3+ in a very selective manner, and hence the developed GQD/300 was successfully used for the metal ion sensing application.
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Liu, Thomas, Claire Tonnelé, Christine Elias, Loïc Rondin, Baptiste Carles, Daniel Medina Lopez, Yannick Chassagneux, et al. "(Invited) Influence of Vibrations on the Emission Properties of Single Graphene Quantum Dots." ECS Meeting Abstracts MA2022-01, no. 9 (July 7, 2022): 741. http://dx.doi.org/10.1149/ma2022-019741mtgabs.
Повний текст джерелаАнотація:
Recent years have shown an increasing number of studies dedicated to new light emitters for diverse applications such as optoelectronics, bio-imaging, and quantum technologies. In this context, graphene quantum dots (GQD) have important assets since bottom-up chemistry allows complete control of the structure, opening the way to wide customization of their electronic, optical, and spin properties [1-3]. The full benefit from these opportunities requires addressing GQD’s intrinsic photophysical properties.To do so, single molecule photoluminescence experiment is a powerfull tool [4]. Here, we highlight the influence of vibrations on GQDs’ optical properties, by comparing optical studies to extensive DFT/TDDFT calculations combined with molecular dynamics simulations. Specifically, we discussed their role in the transitions' oscillator strengths [5]. In order to get deeper in the photophysics of GQD, we investigate the spectroscopy of single GQDs at cryogenic temperatures. In particular, we show a narrowing of the emission lines at low temperature, that allows us to characterize and identify vibrational replicas that are characteristic to GQDs [6]. [1] M. G. Debije, J. Am. Chem. Soc. 2004, 126, 4641 [2] X. Yan, X. Cui, and L.-s. Li, J. Am. Chem. Soc. 2010 132, 5944 [3] A. Konishi et al, J. Am. Chem. Soc. 2010, 132, 11021 [4] S. Zhao et al, Nature Communications, 2018, 9, 3470 [5] T. Liu et al, under review [6] T. Liu et al, in preparation
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Zhang, Jie, Yong-qiang Ma, Na Li, Jing-li Zhu, Ting Zhang, Wei Zhang, and Bin Liu. "Preparation of Graphene Quantum Dots and Their Application in Cell Imaging." Journal of Nanomaterials 2016 (2016): 1–9. http://dx.doi.org/10.1155/2016/9245865.
Повний текст джерелаАнотація:
Objective. This study aims to increase the fluorescence quantum yield by improving the conditions of preparing graphene quantum dots (GQDs) through the solvothermal route and observe the GQDs performance in imaging oral squamous cells.Methodology. The following experimental conditions of GQDs preparation through the solvothermal route were improved: graphene oxide (GO)/N-N dimethyl formamide (DMF) ratio, filling percentage, and reaction time. A fluorescence spectrophotometer was used to measure photoluminescence, and the peak values were compared. Methylthiazolyldiphenyl-tetrazolium (MTT) bromide was used to detect the cytotoxicity of GQDs, which was compared with that of cadmium telluride quantum dots (CdTe QDs). GQDs were cultured with tongue cancer cells. After the coculture, a laser scanning confocal microscope (LSCM) was used to observe cell imaging.Results. The optimal conditions of GQD preparation through the solvothermal route included the following: 10 mg/mL GO/DMF ratio, 80% filling percentage, 12 h reaction time, and 17.4% fluorescence quantum yield. As the cell concentration increased, the GQD and CdTe QD groups exhibited a decreasing cell survival rate, with the decrease in the CdTe QD group being more significant. The LSCM observations showed bright green fluorescence images.Conclusion. The improved experimental conditions increased the fluorescence quantum yield of GQDs. In this study, the prepared GQDs exhibited low cytotoxicity level and satisfactory cell imaging performance.
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Qiu, Zhongzhu, Lin Li, Qunzhi Zhu, Ruitang Guo, Yuan Yao, Congcong Wu, Shengnan Li, and Peng Li. "Physical Stability, Rheology, Thermal Conductivity and Optical and Corrosion Properties of a Graphene Quantum Dot Fluid." Journal of Nanoscience and Nanotechnology 21, no. 10 (October 1, 2021): 5312–18. http://dx.doi.org/10.1166/jnn.2021.19306.
Повний текст джерелаАнотація:
Because of their unique and tunable photoluminescence properties, exceptional physicochemical properties, high photostability, biocompatibility and small size, Graphene quantum dots (GQDs) have received a lot of attention. However, insufficient investigations have been carried out on GQD fluids. In this paper, the properties of a prepared GQD fluid are studied experimentally, involving the physical stability, rheology, thermal conductivity, optical properties and corrosion characteristics. It is found that a highly physically stable GQD fluid could be easily achieved because the selected GQDs are well dispersed. It is also found that the addition of GQDs had a slight effect on the base fluid viscosity, but it could significantly increase the thermal conductivity of the fluid. In addition, the investigation of the optical properties shows that the GQD fluid exhibited high absorption to sunlight. The transmittance of ultraviolet and near-infrared light is close to zero. In contrast, the transmittance of GQDs to visible light is high at low weight concentrations, but significantly decreases with the increase of the proportion of GQDs. The corrosion characteristics of the copper and carbon steel samples in the selected GQD fluid or deionized water were experimentally investigated. It is found that the selected GQD fluid can greatly accelerate the corrosion of copper. However, nearly the same corrosion rate is observed for carbon steel in the GQD fluid as that in deionized water. The high stability, low viscosity, enhanced thermal conductivity and unique optical and corrosion properties allowed the GQD fluid to have excellent potential for applications in the energy sector.
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Walton-Raaby, Max, Riley Woods, and Subha Kalyaanamoorthy. "Investigating the Theranostic Potential of Graphene Quantum Dots in Alzheimer’s Disease." International Journal of Molecular Sciences 24, no. 11 (May 30, 2023): 9476. http://dx.doi.org/10.3390/ijms24119476.
Повний текст джерелаАнотація:
Alzheimer’s disease (AD) is one of the leading causes of death worldwide, with no definitive diagnosis or known cure. The aggregation of Tau protein into neurofibrillary tangles (NFTs), which contain straight filaments (SFs) and paired helical filaments (PHFs), is a major hallmark of AD. Graphene quantum dots (GQDs) are a type of nanomaterial that combat many of the small-molecule therapeutic challenges in AD and have shown promise in similar pathologies. In this study, two sizes of GQDs, GQD7 and GQD28, were docked to various forms of Tau monomers, SFs, and PHFs. From the favorable docked poses, we simulated each system for at least 300 ns and calculated the free energies of binding. We observed a clear preference for GQD28 in the PHF6 (306VQIVYK311) pathological hexapeptide region of monomeric Tau, while GQD7 targeted both the PHF6 and PHF6* (275VQIINK280) pathological hexapeptide regions. In SFs, GQD28 had a high affinity for a binding site that is available in AD but not in other common tauopathies, while GQD7 behaved promiscuously. In PHFs, GQD28 interacted strongly near the protofibril interface at the putative disaggregation site for epigallocatechin-3-gallate, and GQD7 largely interacted with PHF6. Our analyses revealed several key GQD binding sites that may be used for detecting, preventing, and disassembling the Tau aggregates in AD.
Дисертації з теми "GQDs"
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Turchetto, Fabiano. "Um Roadmap para GQS." Pontifícia Universidade Católica do Rio Grande do Sul, 2005. http://hdl.handle.net/10923/1648.
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Previous issue date: 2005Nowadays the organizations need to implement a quality improvement program in order to survive on the competitive market. The Software Quality Assurance (SQA) is directly related to one process area in the SW-CMM and CMMI. This function is responsible by assure that the implanted process is being followed. However, without an adequate and functional SQA structure (activities and roles classified according to maturity levels of this models), the organizations are finding difficulties in achieve a higher maturity level in the SW-CMM and in the CMMI. And the effort expended for some of the SQA activities must be reduced with the time. It because the organizations dominate better your processes along the years. In this context, this research presents a roadmap for GQS. The roadmap aggregates the MEGa model, that objectivities to organize the SQA function, and the “2 Tempos” method to execution of auditorships by sampling. The MEGa is a guide to formulate or reformulate the SQA structure in the organization. The “2 Tempos” method possibility to customizes part of SQA function.
Nos dias atuais as organizações necessitam de um processo de melhoria de qualidade para atuar em um mercado competitivo. A Garantia da Qualidade de Software (GQS), correlata a uma área de processo no SW-CMM e no CMMI, é a função responsável por garantir que o processo implantado está sendo seguido. Entretanto, sem uma estrutura (atividades e papéis relacionados com a maturidade organizacional) de GQS adequada e funcional, as organizações encontram dificuldades em passar para o nível seguinte de maturidade no SW-CMM e no CMMI. Deve-se considerar ainda que o esforço despendido por algumas das atividades de GQS deve ser reduzido com o passar do tempo, uma vez que os processos passam a ser mais bem compreendidos e dominados pela organização. Tendo em vista este quadro, propõe-se um roadmap para GQS. Compõe o roadmap o modelo MEGa, para estruturação da função de GQS, e o método 2 Tempos para execução de auditorias por amostragem. O MEGa funciona como um guia que auxilia a organização na definição ou reformulação da sua estrutura de GQS e o método 2 Tempos torna a customização de parte da função de GQS passível de execução.
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Brogini, Glaucio Giuliano. "GQS-AE - uma abordagem evolucionista para garantia de qualidade de software." Universidade de São Paulo, 2002. http://www.teses.usp.br/teses/disponiveis/55/55134/tde-10012018-150416/.
Повний текст джерелаАнотація:
A exigência por produtos de software com qualidade tem-se mostrado recorrente no mercado dos dias atuais. A fim de que essa qualidade possa se manifestar, vários processos que concorrem para a \"fabricação\" do software necessitam ser muito bem definidos, executados e gerenciados. É, pois, imperativo, que se tenha uma abordagem para Garantia de Qualidade de Software, bem planejada e sistemática, para ser utilizada na avaliação dos produtos e dos processos envolvidos no desenvolvimento de software, e que permita e assegure o uso dos resultados dessa avaliação pelos gerentes e desenvolvedores ao longo de todo o ciclo de desenvolvimento. O que o presente trabalho propõe, então, é a abordagem GQS-AE (uma abordagem evolucionista para garantir a qualidade do software), que descreve a forma como manipular, organizar e gerenciar os recursos - técnicos e humanos - disponíveis em uma empresa de software, sob uma base pré-estabelecida, a fim de que sejam alcançados os objetivos de melhoria da qualidade de tal software. Ressalta-se, porém, que essa abordagem foi concebida de forma simplificada e presa às restrições que normalmente apresenta uma pequena empresa, incapacitada, na grande maioria das vezes, de adaptar modelos já existentes por serem eles mais adequados à realidade de empresas de maior porte.The demand for high-quality software products has shown itself to be recurring nowadays. In order to accomplish such quality, various processes that concur in software \"manufacturing\" have to be very well defined, carried out and managed. It is therefore imperative that there be a systematic Software Quality Assurance approach, catering for the evaluation of ali the products and processes involved in software development and ensuring that evaiuation results are lifecycle-widely available and useful to managers and developers. In response, this work proposes GQS-AE an evolutionary software quality assurance approach describing how to organize and manage the resources - both human and technical - available in a software enterprise, on an aprioristic basis, so as to achieve quality enhancement goals. It is worth noticing that GQS-AE has been designed to be simple and friendly to small businesses, which are seldom at ease to adapt existing models, usually best fit to bigger enterprises.
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Åslund, Carl Fredrik. "Detection of Amphetamine with Graphene Quantum Dots." Thesis, KTH, Tillämpad fysik, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-302566.
Повний текст джерелаАнотація:
Amphetamine abuse is an enduring problem in many developed nations, including Sweden. It causes lasting damage both to its users and in the form of increased strain on healthcare services. It is therefore critical that police be equipped with the tools necessary to rapidly and accurately identify any samples in order to combat this scourge. Current analysis methods rely on large complex machines such as gas-chromatographs. This causes a significant bottleneck as all samples must be sent to lab for analysis. In this report the potential application of graphene quantum dots(GQDs) as a sensor for amphetamine has been studied. These offer a potentially quick and cheap analysis method that could be integrated into an easily portable detector. It was found that GQDs synthesised by a simple method from citric acid shows increased photo-luminescence in the presence of amphetamine. The response is largely linear with increasing concentrations of amphetamine within an interval of 1mM-200mM. This indicates they may very well serve as a sensing element of an amphetamine detector.Amfetaminmissbruk har länge varit ett problem i många industrialiserade länder, inklusive Sverige. Det skapar långvariga skador både på dess användare och i form av ökade kostnader för hälsovården. Det är därför kritiskt att polisen ges de verktyg som behövs för att snabbt och precist kunna analysera prov. Nuvarande analysmetoder använder sig av stora avancerade maskiner so som gas-kromatografer. Detta skapar en flaskhals då alla prov som tas måste skickas till labb för analys. I denna rapport har användningen av grafen kvantprickar (GQD) som en sensor för amfetamin studerats. Dessa har potentialen att ge en snabb och enkel analysmetod som skulle kunna integreras i portabel sensor. GQD:er syntetiserade med en simpel metod från citronsyra visas i dessa experiment ha ökad fotoluminiscens när de är lösta tillsammans med amfetamin. Denna respons är linjär relativt till koncentrationen av amfetamin inom intervallet 1mM-200mM. Detta indikerar att dessa GQD:er mycket väl kan användas som ett sensorelement i en amfetamindetektor.
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Lantz, Linnea. "Evaluation of the Robustness of Different Classifiers under Low- and High-Dimensional Settings." Thesis, Uppsala universitet, Statistiska institutionen, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-385554.
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This thesis compares the performance and robustness of five different varities of discriminant analysis, namely linear (LDA), quadratic (QDA), generalized quadratic (GQDA), diagonal linear (DLDA) and diagonal quadratic (DQDA) discriminant analysis, under elliptical distributions and small sample sizes. By means of simulations, the performance of the classifiers are compared against separation of mean vectors, sample size, number of variables, degree of non-normality and covariance structures. Results show that QDA is competitive under most settings, but can be outperformed by other classifiers with increasing sample size and when the covariance structures across classes are similar. Other noteworthy results include sensitivity of DQDA to non-normality and dependence of the performance of GQDA on whether sample sizes are balanced or not.
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Wang, Shujun. "Synthesis of Graphene Quantum Dots and Their Applications in Sensing and Light Harvesting." Thesis, Griffith University, 2017. http://hdl.handle.net/10072/366102.
Повний текст джерелаАнотація:
Graphene quantum dot (GQD) is a derivative of 2D material graphene. It normally refers to small fragments of graphene having lateral size below 100nm. Not only do GQDs inherit some of the wonder properties of bulk graphene, but they possess properties unique from bulk graphene due to the quantum confinement and edge effects. As an emerging material, GQDs presents a new open field for broad
investigations, from synthesis, explanation of properties to promising applications including sensing, bio-imaging, nanomedicine (e. g. drug delivery), energy conversion (e. g. photovoltaic devices and photocatalyst) optoelectronics, spintronics etc. This PhD project is dedicated to three correlated aspects of GQDs: 1) development of new methods for synthesis of GQDs; 2) mechanistic studies of the
photoluminescence (PL) possessed by GQDs, and; 3) the applications of GQDs in sensing and light harvesting.Thesis (PhD Doctorate)
Doctor of Philosophy (PhD)
Griffith School of Engineering
Science, Environment, Engineering and Technology
Full Text
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Carvalho, Julia Pinto de. "Práticas de qualidade na integração da cadeia de suprimentos e seus impactos sobre o desempenho: uma ótica sobre a practice-based-view (PBV)." reponame:Repositório Institucional do FGV, 2018. http://hdl.handle.net/10438/24320.
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A integração da cadeia de suprimentos (ICS) trata da colaboração estratégica de processos organizacionais internos e entre os membros da cadeia de suprimentos, e as pesquisas desenvolvidas neste novo milênio apontam para a importância de se integrar as práticas internas aos fornecedores e aos clientes externos. O gerenciamento da qualidade da cadeia de suprimentos (GQCS) amplia a adoção das práticas, que antes eram focadas na empresa e no produto, enfatizando a integração dos membros da cadeia de suprimentos com o objetivo de melhorar continuamente a qualidade de produtos, serviços ou processos. Vários estudos da área abordam práticas de qualidade e integração simultaneamente na composição dos seus constructos, mas sem averiguar como estes conceitos se relacionam, e apesar de haver estudos recentes que quantificam a relação entre integração e práticas de qualidade, nenhum deles avalia o efeito da integração enquanto moderadora na relação entre práticas de qualidade e desempenho. Assim, a principal pergunta de pesquisa questiona como os diferentes níveis de integração da cadeia de suprimentos afetam os resultados de desempenho resultantes da adoção das práticas de qualidade, e para responde-la, esta pesquisa, guiada aos olhos da practice-based-view (PBV), possui abordagens qualitativa e quantitativa, nas quais uma meta-análise consolidou quantitativamente a correlação entre práticas de qualidade e desempenho, os resultados decorrentes de uma survey quantificaram como essas práticas, moderadas pelos diferentes níveis de integração, impactam sobre o desempenho, e por fim, averigou-se, por meio de entrevistas semi-estruturadas, como a eficácia da adoção das diferentes práticas de qualidade interferem nos diferentes níveis de integração. A meta-análise, que mapeou 562 correlações em 38 artigos abrangendo 16.333 unidades amostrais, mostrou que a correlação entre a adoção de práticas de qualidade e o desempenho organizacional foi de 0,182 e de 0,242 para os desempenhos organizacional e operacional, respectivamente. Os resultados decorrentes da survey aplicada à 92 gerentes e líderes de qualidade e de supply chain apontam para o fato de que a integração exerce um efeito moderador significativo sobre a relação entre a adoção de práticas de qualidade e o desempenho operacional. De maneira geral, níveis maiores de integração apresentam melhores resultados de desempenho, ou seja, quando a empresa integra-se apenas internamente, os resultados de desempenho podem culminar em prejuízo, e este efeito tende a se diluir conforme o nível de integração aumenta. Também identificou-se efeito significante da experiência do líder. Por fim, um total de 22 entrevistas semi-estruturadas apontam para o fato de que muitas vezes a integração das práticas de qualidade desenvolve-se por necessidade, como quando uma empresa precisa acessar o ambiente da cadeia para solucionar algum problema de qualidade específico de um produto ou matéria-prima, ou quando necessitam apresentar certos níveis de qualidade, via certificações, por exemplo, para fechar contratos com clientes importantes que trarão ganhos significantes para o desempenho. Com a evolução da integração, parte dela pode tornar-se até mesmo parte da cultura da empresa estabelecendo-se uma rotina integrativa na qual os parceiros aprendem por meio da troca diária de informações que direcionam à novas oportunidades de melhoria pontual e contínua. Por fim, a pesquisa aponta para a inovação como fator mediador desta relação de moderação da integração entre práticas de qualidade e do desempenho, direcionando assim pesquisas futuras.
The supply chain integration (SCI) deals with the strategic collaboration between internal organizational processes and between members of a supply chain. Several studies conducted since the beginning of the new millennium shows the importance of integrating internal practices with suppliers and external customers. Supply Chain Quality Management (SCQM) increases the adoption of practices previously directed towards company and product, highlighting the importance of integrating supply chain members, with the goal of continuous quality improvement of products, services or processes. Although there are numerous studies that emphasize practices of quality and integration simultaneously in the elaboration of their constructs, they do not investigate how these concepts relate to each other. And while there have been recent studies that quantify the relationship between integration and quality practices, none of them have evaluated the effect of integration with regard to mediating the relationship between quality and performance practices. Therefore, this research’s main research question deals with how the different levels of supply chain integration affect the performance results originated from the adoption of quality practices. In other to answer this question, this research will be based on practice-based-view (PBV) and adopt qualitative and quantitative methods. It will use a meta-analysis, a quantitative method to combine data from quality and performance practices. Survey results measured how these practices, moderated by different levels of integration, impact performance. Finally, it was identified via semistructured interviews how the adoption of different quality practices interferes at different levels of integration. The meta-analysis mapped 562 correlations in 38 articles covering 16.333 sample units. It shows the correlation between the adoption of quality practices and organizational performance to be 0.182 and 0.242 for organizational and operational performance, respectively. The results of a survey applied to quality and supply chain managers and leaders revel that integration has a significant moderating effect on the relationship between the adoption of quality practices and operational performance. In general, higher levels of integration present better performance results. In other words, when the company integrates only internally, performance results can lead to loss. The effect tends to decrease as the level of integration rises. A significant effect from the leader's experience was also identified. Finally, a total of 22 semi-structured interviews reveal that more often than expected, the integration of quality practices is developed by necessity, such as when a company needs to access its supply chain to solve a specific quality problem related to a product or a raw material, or when a company is required to disclose quality levels through certifications in order to be able to close contracts with key customers which will bring significant gains to the company’s performance. As integration advances, it has the potential to be assimilated into the company’s culture, thereby establishing an integrative routine from which partners are able to learn through daily exchange of information, in turn leading to new opportunities for continuous improvement. Finally, the research shows innovation to be a mediator factor in the relation and integration between quality practices and performance, which will be crucial to direct future research.
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GANGWAR, ANSHU. "INVESTIGATING EFFICIENCY OF GLUCOSE-DERIVED GRAPHENE QUANTUM DOTS IN PHOTOCATALYSIS." Thesis, 2023. http://dspace.dtu.ac.in:8080/jspui/handle/repository/19805.
Повний текст джерелаАнотація:
Graphene is unique in that it has a zero bandgap, unlike graphene quantum dots. However,
the functionalization of graphene allows a significant alteration in its properties. Here,
graphene quantum dots (GQDs) were fabricated in an aqueous medium via carbonization,
using glucose as a carbon precursor at ambient temperature. The process is
environmentally benign and cost-effective with de-ionized water as a solvent and
ammonia as a catalyst. The chemical compositional and morphological analysis of GQDs
was examined by FTIR and HRTEM, respectively. The as-synthesized GQDs were
spherical and showed an absorption peak at 280 nm. Additionally, they exhibit strong
emission in the blue region at 350 nm and display excitation wavelength-dependent
features. The resulting GQDs have a bandgap of 3.81 eV. The study evaluated the catalytic
activity of GQDs under NaBH4 mediated photoreduction and compared their efficiency
in degrading the organic rhodamine B dye under visible and UV light for 16 minutes. The
outcome of the study revealed that GQDs possess exceptional photocatalytic activity.
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Liu, Jing-Yuan, and 劉靖圓. "High Performance Asymmetric Capacitive Deionization Induced by Fe-MOF/rGO and GQDs@PANI/rGO Ion-selective Electrodes." Thesis, 2019. http://ndltd.ncl.edu.tw/handle/6cy2xv.
Повний текст джерелаАнотація:
碩士國立交通大學
環境工程系所
107
Electrode materials for asymmetric capacitive deionization (ACDI), by combining capacitive carbon material and metal oxide electrode, have emerged as a promising method for water desalination, which enable higher ion removal capacity in comparison with devices containing only carbon materials. In this work, nanocomposites of Fe-MOF (iron metal-organic frameworks) synthesized by solvothermal method and one dimensional GQDs@PANI synthesized by chemical polymerization were combined with two dimensional reduced graphene oxide using hydrothermal method at various weight ratios to serve as an electrode material for CDI. The synthesized Fe-MOF/rGO and GQDs@PANI/rGO were systematically characterized by SEM, TEM, EDX, XPS, TGA, XRD, Raman, BET and their electrochemical properties were evaluated by using cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). rGO prepared by hydrothermal exhibited a high specific capacitance of 208.4 F g-1 at 5 mV s-1 and retained 142.3 F g-1 at a high scan rate of 100 mV s-1, and Fe-MOF showed an excellent specific capacitance of 310.8 F g-1 at 5 mV s-1, which is attributed to the high specific surface area of 444.5 m2 g-1 and 2889.7 m2 g-1, respectively. Moreover, the synthesized Fe-MOF/rGO and GQDs@PANI/rGO exhibited high specific capacitance of 473.8 F g-1 and 267.2 F g-1 at 5 mV s-1 in 1 M Na2SO4 solution, showed the superior specific surface area of 896.9 m2 g-1 and 208.6 m2 g-1 based on N2 adsorption-desorption isotherms. The prepared nanocomposite materials have been used as cathode and anode electrodes for asymmetric CDI. The results showed that the asymmetric GPr‖FeMr electrode exhibits an excellent electrosorption capacity for sodium ion in a 4.3 mM NaCl solution. The removal efficiency for sodium ions is 55.5%, the regeneration performance is 97.4%, and the SEC is 44.6 mg g−1 at an applied voltage of 1.2 V in the batch and continuous flowing model, which is about 1.7-3.2 and 1.1-1.4 times higher than the other symmetric (rGO‖rGO, GPr‖GPr and FeMr‖FeMr) and asymmetric electrodes (rGO‖GPr and rGO‖FeMr), respectively. In addition, the asymmetric GPr‖FeMr electrodes show excellent electrosorption capacity and high stability toward high concentration of sodium ion which is 5000 mg L−1, and the SEC is 358.5 mg g−1. For the ion competition environment of sodium ion (500 mg L−1) and calcium ion, the SECs of sodium ion are 52.3, 48.6 and 42.6 mg g−1 when the calcium ion are 100, 250 and 500 mg L−1, respectively. Overall, this study provides a promising novel material for water treatment technology and significantly improves the CDI performance.
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Yom, Tiana. "Looking At The Whole Child Through Student Health Profiles: A Latent Class Analysis of CDC 2019 National Youth Risk Behavior Survey Data." Thesis, 2021. https://doi.org/10.7916/d8-gqbs-4v30.
Повний текст джерелаАнотація:
The purpose of this research is to discover the extent to which there is a typology of students’ health risk behaviors and to what extent are those typologies associated with academic achievement using the 2019 national Youth Risk Behavior Survey (YRBS) dataset. This is a secondary data analysis study using a national representative sample (n=11,410) of high school students, grades 9 to 12, in the United States. YRBS is a national school-based, paper-based 99-item survey used to assess 121 health-related behaviors among all high school students in the United States and is biennially conducted by the Centers for Disease Control and Prevention (CDC, 2020). While research efforts on health and academic achievement is vastly growing, there is a limited number of studies that are analyzing multiple health-risk behaviors concurrently as well as exploring their potential impacts on educational outcomes.
Furthermore, previous studies have utilized cluster and/ or factor analyses. However, this statistical approach will show how students are clustered into groups and does not provide information such as the probability that a given student is bullied or suicidal. A 3-step Latent Class Analysis (LCA) was conducted to identify and understand the various profiles of students who experienced and/ or were exposed to certain health-risk behaviors. The health-risk behaviors of interest, the latent variables, were school-related violence, physical activity, screen time, and sleep. Using LCA, results show that there are four significantly different typologies, or profiles, of student health-risk behaviors: Level 1 The Most Support Needed (TMSN), Level 2 Suicide Prevention Needed (SPN), Level 3 Coping Mechanism for Bullying Needed (CMBN), Level 4 Least Support Needed (LSN). In tandem, contextual factors such as age, sex, grade level, race and ethnicity were significantly associated with the odds of belonging to some of the groups. This study is connected to longer-term work. Implications of these groupings on school policies, student health outcomes, and building a school-based coordinated health system will be discussed.
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Su, Pai-Han, and 蘇柏翰. "Preparation and Properties of polyaniline/GQD nanocomposites and their applications on gel type supercapacitor." Thesis, 2015. http://ndltd.ncl.edu.tw/handle/27642089003731753918.
Повний текст джерелаАнотація:
碩士國立臺灣大學
材料科學與工程學研究所
103
The main idea of this thesis was to fabricate a flexible electrode with facile process for gel type supercapacitor. In-situ chemical polymerization of aniline was employed for the growth of PANI nanowire array on graphite foil with high surface area. We used SEM, TGA and electrochemical measurement including Galvanostatic charge discharge, cyclic voltammetry and EIS to characterize the PANI electrode that synthesized in different concentrations of aniline. The correlation between the capacitance and surface morphology of PANI polymerized in different aniline concentrations were investigated. When the concentration of aniline for reaction was 0.01 M, nanowire array was fabricated with the optimized specific capacitance reaching 737.29 F/g at 1 A/g and still remaining 474.60 F/g at 11 A/g. To further improve the specific capacitance, PANI electrode was physisorbed with GQDs which were prominent in their oxygen-related chemical functionalities on the edge site. Accordingly, negative-charged GQDs could adsorb on positive-charged PANI easily as evidenced by FTIR-ATR. In addition, from TEM images, the surface of PANI/GQDs would not be reduced because of the small particle size and great dispersity of GQDs. Electrochemical measurements were also conducted to support the observed enhancement of capacitive performance. For PANI/GQD nanocomposites prepared by immersing PANI in 1.5 mg/ml GQDs suspension, the best specific capacitance obtained was 965.38 F/g at 1 A/g, ~30% higher than that without GQDs. EIS measurements also confirmed that both interface and electron charge transfer resistances were decreased significantly. It is believed that the GQDs on the PANI surface could serve as an electron funnel facilitating the charge transfer between the interfaces and enhancing faradaic redox reaction. To overcome the leakage problem of liquid type electrolyte, we fabricated the gel type supercapapcitor with PANI/GQDs composite electrode and GO-doped EMITFSI ionic liquid. Doping with GO, the ion conductivity of EMITFSI would increase significantly because strong Coulombic force between GO and EMITFSI hindered the motion of molecule and GO as a 3D network acted like an ion “highway” throughout the gel electrolyte. When 4 wt% of GO was added to the EMITFSI, the gel point was reached. The best specific capacitance of 151.06 F/g at 1 A/g was also obtained. Cycle number test of charge-discharge indicated that the supercapacitor with Go-doped gel electrolyte had better durability than that with aqueous electrolyte.
Книги з теми "GQDs"
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Chambers, Gawayne. GQ's Quotes. Independently Published, 2021.
Знайти повний текст джерелаЧастини книг з теми "GQDs"
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Kharangarh, Poonam R. "Synthesis and Characterization of MnCo2O4-GQDs Nano-composites for Supercapacitor Electrodes." In The Minerals, Metals & Materials Series, 129–37. Cham: Springer International Publishing, 2022. http://dx.doi.org/10.1007/978-3-030-92381-5_13.
Повний текст джерела
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Barin, Gabriela Borin, Paulo T. Araujo, Iara de Fatima Gimenez, and Antonio G. Souza Filho. "Characterization of Nanocarbons: From Graphene to Graphene Nanoribbons (GNRs) and Quantum Dots (GQDs)." In Recent Advances in Complex Functional Materials, 315–38. Cham: Springer International Publishing, 2017. http://dx.doi.org/10.1007/978-3-319-53898-3_13.
Повний текст джерела
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Kováčová, Mária, Eva Špitalská, and Zdenko Špitálský. "Light-Activated Polymer Nanocomposites Doped with a New Type of Carbon Quantum Dots for Antibacterial Applications." In Urinary Stents, 315–24. Cham: Springer International Publishing, 2022. http://dx.doi.org/10.1007/978-3-031-04484-7_25.
Повний текст джерелаАнотація:
AbstractCarbon quantum dots (CQDs) are relatively new carbon allotrope. It triggered an investigation of new CQD research of synthesis, properties CQDs, and applications. CQDs are quasispherical carbon particles with a size less than 10 nm with crystalline sp2 cores of graphite and quantum effects. A subclass of CQDs are graphene quantum dots (GQDs), and they have a structure of one or several graphene layers with diameter < 10 nm with higher crystallinity than CQDs. CQDs also play an important role in medicine. CQDs are used in intracellular ion detection, toxin detection, pathogen, vitamin, enzyme, protein, nucleic acid, and biological pH value determination. Despite the broad range of biomedical applications, we would like to focus on antibacterial properties of pure CQDs and their polymer composites. The antibacterial effect of CQDs is based on noninvasive photodynamic therapy (PDT). PDT can cause a specific biological response on the cellular or subcellular level, such as apoptosis, programmed death, or necrosis, a nonprogrammed pathway. CQDs are a very promising new antibacterial nanoparticles.
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Gulati, Shikha, Sanjay Kumar, and Suvidha Sehrawat. "Green and Environment-Friendly Graphene Quantum Dots (GQDs) with State-of-the-Art Performance for Sustainable Energy Conversion and Storage." In Innovations in Green Nanoscience and Nanotechnology, 147–66. Boca Raton: CRC Press, 2022. http://dx.doi.org/10.1201/9781003319153-10.
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Badia, Antonio. "Implementation and Optimization of Standard GQs." In Advances in Database Systems, 55–72. Boston, MA: Springer US, 2009. http://dx.doi.org/10.1007/978-0-387-09564-6_5.
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Bae, Ihn-Han, and Sun-Jin Oh. "A GQS-Based Adaptive Mobility Management Scheme Considering the Gravity of Locality in Ad-Hoc Networks." In Computational Science and Its Applications – ICCSA 2005, 169–76. Berlin, Heidelberg: Springer Berlin Heidelberg, 2005. http://dx.doi.org/10.1007/11424826_18.
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Pablo González-Castillo, Juan, Esdras Alfredo Zamora-Morán, and Lourdes Rodriguez-Fragoso. "Advances in Graphene Platforms for Drug Delivery in Cancer and Its Biocompatibility." In Drug Carriers [Working Title]. IntechOpen, 2022. http://dx.doi.org/10.5772/intechopen.103688.
Повний текст джерелаАнотація:
In the past decade, studies on the biomedical applications of graphene quantum dots (GQDs) have increased substantially, especially those related to cancer therapy. Experimental evidence has shown that GQD platforms do not merely serve for drug delivery but have multifunctional properties: their surface also allows several types of molecules to be joined and has photothermal properties that, when combined, make therapies more effective. Most studies have shown evidence of this specificity and therapeutic efficacy at the in vitro level. There is also evidence for potential use in the monitoring of cellular events given the high-quality bioimages that can be obtained with this type of nanomaterial. However, the application of this nanotechnology has stalled due to the lack of available biosafety and biocompatibility studies. This chapter addresses the advances in the use of GQD platforms for drug delivery and the biocompatibility studies reported so far.
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Bandara, T. M. W. J., T. M. A. A. B. Thennakoon, and G. B. M. M. M. Nishshanke. "Preparation, characterization, and applications of graphene-based quantum dots (GQDs)." In Functional Materials from Carbon, Inorganic, and Organic Sources, 21–69. Elsevier, 2023. http://dx.doi.org/10.1016/b978-0-323-85788-8.00007-0.
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Sakaguti, Luiz Gustavo, Leonardo Zavilenski Fogaça, Camila Fabiano de Freitas, Wilker Caetano, Vagner Roberto Batistela, and Mara Heloisa Neves Olsen Scaliante. "GQD purification study obtained by bottom-up route aiming at the production of photocatalysts." In METHODOLOGY FOCUSED ON THE AREA OF INTERDISCIPLINARITY- V1. Seven Editora, 2023. http://dx.doi.org/10.56238/methofocusinterv1-070.
Повний текст джерелаАнотація:
Recent studies have shown that heterostructures composed of metal semiconductors (SC) and graphene quantum dots (QDs) have a photocatalytic performance considerably higher than that of intrinsic metallic semiconductors, this is because the GQDs reduce the electronic recombination on the surface of the CS, being still associated with the displacement of the absorption band to larger wavelengths. In the present work, graphene quantum dots were synthesized through commercial lignin (LcGQD), using nitric acid for depolymerization followed by a hydrothermal process. Analyses of the material demonstrated an average particulate size of 10.9 nm, UV-Vis absorption similar to that of other structures described in the literature, but without the presence of nitrogen peaks in the carbon structure, besides a remarkable specificity in fluorescence. The LcGQD then has great potential for use in photocatalysis, sensors, and optoelectronics.
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Kalkal, Ashish, and Gopinath Packirisamy. "Recent Advances on Carbon Nanostructure-Based Biosensors." In Current and Future Developments in Nanomaterials and Carbon Nanotubes, 19–38. BENTHAM SCIENCE PUBLISHERS, 2022. http://dx.doi.org/10.2174/9789815050714122030005.
Повний текст джерелаАнотація:
Carbon-based nanostructured materials have derived substantial attention as novel functional materials towards the fabrication of various biosensing platforms owing to their interesting physicochemical and optoelectronic properties, as well as desired surface functionalities. These nanomaterials provide increased and oriented immobilization of biomolecules along with maintaining their biological activity in view of their lower cytotoxicity and higher biocompatibility. The integration of carbon nanomaterials with biosensing platforms has provided new opportunities and paved the way for the efficient detection of various biomolecules and analytes. These nanostructured materials-based biosensors have improved biosensing characteristics, including broader linear detection range, lower detection limit, better selectivity, and higher sensitivity. This chapter summarizes the results of different electrochemical and fluorescent biosensors related to various nanostructured carbon materials, namely carbon nanotubes (CNTs), graphene and its derivatives (reduced graphene oxide (rGO), graphene oxide (GO), graphene quantum dots (GQDs) and carbon dots (CDs).
Тези доповідей конференцій з теми "GQDs"
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Wei, Junhua, and Jenny Qiu. "Tunable Optical Properties of Graphene Quantum Dots by Centrifugation." In ASME 2013 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2013. http://dx.doi.org/10.1115/imece2013-64756.
Повний текст джерелаАнотація:
In this work, tunable optical properties of graphene quantum dots (GQDs) were achieved by centrifugation method. GQDs prepared through intercalating and exfoliating commercially available stacked graphene nanofibers were separated into two samples with different mean sizes by centrifugation. The separated GQD samples were characterized by transmission electron microscope (TEM). The optical properties of the GQD samples were measured by UV-visible and photoluminescence spectroscopy. The characterization results demonstrated that the UV and photoluminescence of GQDs were highly correlated with their sizes and surface chemistry. As the diameters of GQDs reduced, the UV peaks of the GQD blue shift, and the photoluminescence of PL red shift, indicating that the centrifugation method can be used to efficiently achieve tunable optical properties from as-synthesized GQD.
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Su, Siheng, Carla B. Shelton, and Jingjing Qiu. "Size-Dependent Antibacterial Behavior of Graphene Quantum Dots." In ASME 2013 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2013. http://dx.doi.org/10.1115/imece2013-64872.
Повний текст джерелаАнотація:
In this study, the antibacterial behavior of differing sized graphene quantum dots (GQDs) was studied. The gram negative bacteria, Escherichia coli (E. coli), were used as the bacteria mode. Different sized GQDs with tunable fluorescent colors were acquired by a gel-filtration method. The size, surface chemistry, and photoluminescence properties of GQDs were characterized, respectively. The viability of GQDs treated bacteria was determined by the standard plate counting method. Moreover, the reactive oxidative species (ROS) level was detected by the 3-(4,5-Dimethylthiazol-2-yl)-2,5-Diphenyltetrazolium Bromide (MTT) method. The integrality of the bacteria membrane was observed under the scanning electron microscopy (SEM). The experimental results indicated that GQDs demonstrated size-dependent and surface chemistry-dependent antibacterial behaviors. This research provided insightful guidelines in the selection of suitable GQDs for their potential bioapplications.
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Kulah, Jonathan, and Ahmet Aykaç. "Synthesis and Characterization of Graphene Quantum Dots Functionalized Silver Nanoparticle from Moringa Oleifera Extracts." In 6th International Students Science Congress. Izmir International Guest Student Association, 2022. http://dx.doi.org/10.52460/issc.2022.050.
Повний текст джерелаАнотація:
Graphene quantum dots (GQDs) are famously known for large surface area, good dispersibility, good conductivity, and high transparency with good photochemical, electrochemical, and optical properties that are utilized in many biomedical and biotechnological applications. Interestingly, GQDs were reported to serve as an excellent reducing reagent in the synthesis of noble metal nanoparticles such as silver nanoparticles (AgNPs). Moreover, GQDs eradicate the limitation of impurities of AgNPs synthesized using plant extracts as a stabilizer and reducing agents. Therefore, we experimented GQDs synthesis from moringa oleifera (MO) plant extracts compared to citric and urea synthesized GQDs. And used the synthesized GQDs to synthesize, reduce and functionalize AgNPs. MO contains about 110 compounds, high nutrients, vitamins, oleic oil, and phytoconstituents such as alkaloids, flavonoids, glucosinolates, saponins, tannins, terpenes, steroids, phenolic acids, which suggested to us that, MO extracts can serve as a capping agent in the synthesis of nanoparticles. Initially, MO leaves and seeds water phase extracts were obtained by overnight distillation and lyophilized to create a stock solution of 1mg/ml. Next, following Das, R. et al and slightly modifying the followed method by varying the MO extract concentration from 20µL to 60 µL, AgNPs were synthesized by hydrothermal method. GQDs were separately synthesized adopting Tran, H.V. et al method and later added to the AgNPs forming a more stable hybrid structure that was characterized using the UV-vis spectroscopy (UV-Vis), Nano zeta sizer, Raman spectroscopy, and the Fourier Infrared transmission resonance (FTIR). As the concentration of MO extract increased, the color change intensity increased symbolizing the formation of AgNPs while the luminous bright solutions under the UV light symbolized the formation of GQDs. This study lay the foundation for further research and analysis to be done on the nanozyme or biosensor application of enhanced functionalized and stable hybrid AgNPs with GQDs.
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Mohan, Sunil, and Sunil K. Khijwania. "Graphene oxide Quantum dots (GQDs) based optical fiber humidity sensor." In Optical Fiber Sensors. Washington, D.C.: Optica Publishing Group, 2022. http://dx.doi.org/10.1364/ofs.2022.th4.37.
Повний текст джерелаАнотація:
A novel optical fiber humidity sensor employing GQDs diffused microstructure sensing cladding is reported. Sensor exhibits linear sensitivity (0.0679dB/%RH) which is 7 times higher in comparison to the sensor based on pure silica nanostructured cladding.
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Gorav, Gorav, Vrushali Khedekar, Geetha K. Varier, and P. Nandakumar. "Enhanced Uptake and Retention of Graphene Quantum Dots in HeLa Cell Nuclei." In Bio-Optics: Design and Application. Washington, D.C.: Optica Publishing Group, 2023. http://dx.doi.org/10.1364/boda.2023.jtu4a.6.
Повний текст джерелаАнотація:
The nuclear pore complex (NPC) is an intricate protein structure located on the nuclear envelope that functions as the sole gateway for nuclear cytoplasm transport. Our experimental studies show the dual uptake rates of GQDs in HeLa nuclei indicate two phenomena occurring simultaneously. Export studies confirm bidirectionality and retention.
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Peter, I. John, N. Rajamanickam, K. Ramachandran, and P. Nithiananthi. "On the ZnO/graphene quantum dots (GQDs) based dye sensitized solar cells." In INTERNATIONAL CONFERENCE ON RENEWABLE ENERGY RESEARCH AND EDUCATION (RERE-2018). Author(s), 2018. http://dx.doi.org/10.1063/1.5047991.
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Ricchezza, Victor J., Heather R. Houlton, Jeffrey R. Raker, Jennifer M. Wenner, and Jeffrey G. Ryan. "DEVELOPMENT AND VALIDATION OF THE GEOSCIENCE QUANTITATIVE PREPARATION SURVEY (GQPS)." In GSA Annual Meeting in Indianapolis, Indiana, USA - 2018. Geological Society of America, 2018. http://dx.doi.org/10.1130/abs/2018am-319303.
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Padmavathi, B., and V. Vijayakumar. "A Robust and Efficient GQD based biosensor for wearable applications." In 2022 International Conference on Innovative Computing, Intelligent Communication and Smart Electrical Systems (ICSES). IEEE, 2022. http://dx.doi.org/10.1109/icses55317.2022.9914068.
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Aguiar, Yuska P. C., Juliana Saraiva, Jorge Dias, and Yuri Malheiros. "O Ensino Integrado de Gestão de Qualidade de Software e Engenharia de Software Aplicada como Modelo de Educação Interdisciplinar: Um Relato de Experiência no Ensino de Graduação." In XIV Simpósio Brasileiro de Qualidade de Software. Sociedade Brasileira de Computação - SBC, 2015. http://dx.doi.org/10.5753/sbqs.2015.15230.
Повний текст джерелаАнотація:
O processo ensino-aprendizagem de disciplinas relacionadas à Qualidade de Software pode ser dificultado pela natureza abstrata dos conceitos ensinados. Este artigo apresenta o relato de experiência da aplicação de uma abordagem interdisciplinar entre as disciplinas de Gestão de Qualidade de Software (GQS) e Engenharia de Software Aplicada (ESA), onde os processos, projetos e produtos desenvolvidos na disciplina de ESA foram avaliados pelos alunos de GQS. Foram envolvidos 38 alunos avaliando 5 projetos reais. Com adoção desse modelo, foi possível observar uma melhor compreensão do conteúdo pelos alunos, a aprovação do método de ensino e o melhor preparo dos alunos para o mercado da indústria de software.
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Yeoh, Wei-Lun, Yi-Jhen Jhang, Shu-Yu Kuo, and Yao-Hsin Chou. "Automatic Stock Trading System Combined with Short Selling Using Moving Average and GQTS Algorithm." In 2018 IEEE International Conference on Systems, Man, and Cybernetics (SMC). IEEE, 2018. http://dx.doi.org/10.1109/smc.2018.00272.
Повний текст джерела