scholarly journals Features of the MBE growth of nanowires with quantum dots on the silicon surface

2021 ◽  
Vol 2086 (1) ◽  
pp. 012032
Author(s):  
R R Reznik ◽  
K P Kotlyar ◽  
A I Khrebtov ◽  
G E Cirlin
Keyword(s):  
Quantum Dots ◽  
The Body ◽  
Hybrid Nanostructures ◽  
Silicon Substrates ◽  
Mbe Growth ◽  
Wide Range ◽  
Material Systems ◽  
Hybrid Iii ◽  
New Generation ◽  
Element Base

Abstract The development of a new semiconductor element base is necessary to create a new generation of applications. At present time, the synthesis of high-quality hybrid nanostructures based on III-V quantum dots in the body of nanowires of a wide range of material systems is an urgent and important task. In work hybrid III-V nanostructures based on QDs in the body of NWs in GaP/GaAs and AlGaP/InGaP material systems were synthesized in on silicon substrates and their physical properties were investigated.

scholarly journals III-V nanowires with quantum dots: MBE growth and properties

2021 ◽  
Vol 2015 (1) ◽  
pp. 012124
Author(s):  
R R Reznik ◽  
K P Kotlyar ◽  
V O Gridchin ◽  
I V Ilkiv ◽  
A I Khrebtov ◽  
...  
Keyword(s):  
Quantum Dots ◽  
Optical Properties ◽  
Optoelectronic Devices ◽  
Optical Quality ◽  
Silicon Substrates ◽  
Single Photons ◽  
Mbe Growth ◽  
Pl Spectrum ◽  
Good Optical Quality

Abstract We demonstrate growth of AlGaAs NWs with GaAs QDs and InP NWs with InAsP QDs on silicon substrates. Results of GaAs QDs optical properties study have shown that these objects are sources of single photons. In case of InP NWs with InAsP QDs, the results showed that ~ 100% of homogeneously oriented NWs were formed with good optical quality of this system on a Si(111). PL spectrum peak near 1.3 μm indicates that such system is promising for optoelectronic devices.

MBE growth of InAs/GaAs quantum dots on sintered porous silicon substrates with high optical quality in the 1.3 μm band

2020 ◽  
Vol 31 (6) ◽  
pp. 4605-4610 ◽  
Author(s):  
Mansour Aouassa ◽  
Giorgia Franzò ◽  
Elie Assaf ◽  
Larbi Sfaxi ◽  
Ridha M’Ghaieth ◽  
...  
Keyword(s):  
Quantum Dots ◽  
Porous Silicon ◽  
Optical Quality ◽  
Silicon Substrates ◽  
High Optical Quality ◽  
Mbe Growth

Role of porous silicon/hydrogel composites on drug delivery

2016 ◽  
Vol 3 (1) ◽  
Author(s):  
Denisse Rocha-García ◽  
Antonio Guerra-Contreras ◽  
Sergio Rosales-Mendoza ◽  
Gabriela Palestino
Keyword(s):  
Porous Silicon ◽  
The Body ◽  
In Vivo Studies ◽  
Great Success ◽  
Nanoscale Systems ◽  
Wide Range ◽  
Spatial Presentation ◽  
New Generation

AbstractNanomaterials are applied with great success in biomedical applications as templates for the development of new generation devices, which can be used to solve current health problems. These new nanoscale systems are designed with multifunctions to perform specific and selective tasks. One of the most important applications of this new nanotechnology; focuses on developing new systems for the controlled release of drugs, mainly due to their capability to improve the temporal and spatial presentation of drugs in the body and their ability to protect them from physiological degradation or elimination. Hydrogels, porous silicon (PSi), and PSi-composites have been widely adopted in this field due to their biological, morphological, and physicochemical properties; which can be tuned to obtain sensitive responses to physiological stimuli. Despite the fact that some recent academic papers have shown the benefits of these nanomaterials in a wide range of biological applications, more in vivo studies are needed to take these hybrid systems towards clinical trials. In this mini-review some of the hydrogels, PSi, and PSi-composites latest applications and prospects in this field of science are presented.

Complementary Microscopy Platform for Investigations of Hybrid Nanostructures Comprising Quantum Dots and Plasmonic Particles

2015 ◽  
Vol 1748 ◽  
Author(s):  
Katja Dopf ◽  
Patrick M. Schwab ◽  
Carola Moosmann ◽  
Anne Habermehl ◽  
Uli Lemmer ◽  
...  
Keyword(s):  
Quantum Dots ◽  
Optical Characterization ◽  
Hybrid Nanostructures ◽  
Raman Signal ◽  
Nanoscale Systems ◽  
Characterization Methods ◽  
Atomic Force ◽  
Wide Range ◽  
Nanoparticle Sizes ◽  
Plasmonic Particles

ABSTRACTNanoscale systems combining colloidal quantum dots with plasmonic antennas will pioneer the development of novel nanodevices with tailored optical features for a wide range of applications. The interactions between such nanoparticles strongly depend on the particular distance. We propose the use of an atomic force microscope (AFM) to image and to position quantum dots with respect to plasmonic particles. Additionally, we analyze the arrangements with several optical characterization methods, such as confocal microscopy, fluorescence microscopy and superresolution optical fluctuation imaging (SOFI). These methods support each other and improve the AFM manipulation technique. The AFM tip is perfectly aligned to a focused laser by detecting the Raman signal of the silicon tip. Thus ultimately, we can simultaneously use the topography information with a spatial resolution in the range of the nanoparticle sizes and cross-correlate it with the optical characterization methods.

COMBINATORIAL POLYNOMIALLY COMPUTABLE CHARACTERISTICS OF SUBSTITUTIONS AND THEIR PROPERTIES

2020 ◽  
Vol 7 (2) ◽  
pp. 34-41
Author(s):  
VLADIMIR NIKONOV ◽  
◽  
ANTON ZOBOV ◽  
Keyword(s):  
Mathematical Expectation ◽  
Point Of View ◽  
Small Range ◽  
Computational Point ◽  
Wide Range ◽  
Bijective Function ◽  
The Difference ◽  
Element Base ◽  
Selection Of

The construction and selection of a suitable bijective function, that is, substitution, is now becoming an important applied task, particularly for building block encryption systems. Many articles have suggested using different approaches to determining the quality of substitution, but most of them are highly computationally complex. The solution of this problem will significantly expand the range of methods for constructing and analyzing scheme in information protection systems. The purpose of research is to find easily measurable characteristics of substitutions, allowing to evaluate their quality, and also measures of the proximity of a particular substitutions to a random one, or its distance from it. For this purpose, several characteristics were proposed in this work: difference and polynomial, and their mathematical expectation was found, as well as variance for the difference characteristic. This allows us to make a conclusion about its quality by comparing the result of calculating the characteristic for a particular substitution with the calculated mathematical expectation. From a computational point of view, the thesises of the article are of exceptional interest due to the simplicity of the algorithm for quantifying the quality of bijective function substitutions. By its nature, the operation of calculating the difference characteristic carries out a simple summation of integer terms in a fixed and small range. Such an operation, both in the modern and in the prospective element base, is embedded in the logic of a wide range of functional elements, especially when implementing computational actions in the optical range, or on other carriers related to the field of nanotechnology.

Creating the Wind

2020 ◽  
Vol 2 (4) ◽  
pp. 14-31
Author(s):  
Élodie Dupey García
Keyword(s):  
Indigenous Communities ◽  
The Body ◽  
Historical Sources ◽  
Natural Behavior ◽  
Sensory Experiences ◽  
Identity And Agency ◽  
Wide Range ◽  
Late Postclassic ◽  
Comparative Examination ◽  
Meteorological Phenomenon

This article explores how the Nahua of late Postclassic Mesoamerica (1200–1521 CE) created living and material embodiments of their wind god constructed on the basis of sensory experiences that shaped their conception of this divinized meteorological phenomenon. In this process, they employed chromatic and design devices, based on a wide range of natural elements, to add several layers of meaning to the human, painted, and sculpted supports dressed in the god’s insignia. Through a comparative examination of pre-Columbian visual production—especially codices and sculptures—historical sources mainly written in Nahuatl during the viceregal period, and ethnographic data on indigenous communities in modern Mexico, my analysis targets the body paint and shell jewelry of the anthropomorphic “images” of the wind god, along with the Feathered Serpent and the monkey-inspired embodiments of the deity. This study identifies the centrality of other human senses beyond sight in the conception of the wind god and the making of its earthly manifestations. Constructing these deity “images” was tantamount to creating the wind because they were intended to be visual replicas of the wind’s natural behavior. At the same time, they referred to the identity and agency of the wind god in myths and rituals.

ТЕХНОЛОГИЯ И ПРИМЕНЕНИЕ ЭЛЕКТРОХИМИЧЕСКИХ ПРЕОБРАЗОВАТЕЛЕЙ

2020 ◽  
Vol 96 (3s) ◽  
pp. 450-455
Author(s):  
В.Г. Криштоп ◽  
Д.А. Жевненко ◽  
П.В. Дудкин ◽  
Е.С. Горнев ◽  
В.Г. Попов ◽  
...  
Keyword(s):  
Pressure Sensors ◽  
Engineering Applications ◽  
Electrochemical Systems ◽  
Seismic Sensors ◽  
Microelectronic Technology ◽  
Wide Range ◽  
Electrochemical Transducers ◽  
Element Base ◽  
New Devices

Электрохимические системы очень перспективны для разработки новой элементной базы для микроэлектроники и для использования в широком спектре инженерных задач. Мы разработали новую микроэлектронную технологию для изготовления электрохимических преобразователей (ЭХП) и новые приборы на основе новых электрохимических микроэлектронных чипов. Планарные электрохимические преобразователи могут использоваться в акселерометрах, сейсмических датчиках, датчиках вращения, гидрофонах и датчиках давления. Electrochemical systems are very promising for the development of a new element base for microelectronics, and for use in a wide range of engineering applications. We have developed a new microelectronic technology for manufacturing electrochemical transducers (ECP) and new devices based on new electrochemical microelectronic chips. Planar electrochemical transducers are used in accelerometers, seismic sensors, rotation sensors, hydrophones and pressure sensors.

scholarly journals Transcriptome Profile Alterations with Carbon Nanotubes, Quantum Dots, and Silver Nanoparticles: A Review

Genes ◽  
2021 ◽  
Vol 12 (6) ◽  
pp. 794
Author(s):  
Cullen Horstmann ◽  
Victoria Davenport ◽  
Min Zhang ◽  
Alyse Peters ◽  
Kyoungtae Kim
Keyword(s):  
Carbon Nanotubes ◽  
Quantum Dots ◽  
High Throughput Sequencing ◽  
The Body ◽  
Rna Seq ◽  
Mechanisms Of Toxicity ◽  
Promising Tool ◽  
Engineered Nanomaterial ◽  
Next Generation Sequencing Ngs ◽  
Transcriptomic Changes

Next-generation sequencing (NGS) technology has revolutionized sequence-based research. In recent years, high-throughput sequencing has become the method of choice in studying the toxicity of chemical agents through observing and measuring changes in transcript levels. Engineered nanomaterial (ENM)-toxicity has become a major field of research and has adopted microarray and newer RNA-Seq methods. Recently, nanotechnology has become a promising tool in the diagnosis and treatment of several diseases in humans. However, due to their high stability, they are likely capable of remaining in the body and environment for long periods of time. Their mechanisms of toxicity and long-lasting effects on our health is still poorly understood. This review explores the effects of three ENMs including carbon nanotubes (CNTs), quantum dots (QDs), and Ag nanoparticles (AgNPs) by cross examining publications on transcriptomic changes induced by these nanomaterials.

Development and Validation of a New Scoring Tool to Evaluate the Clinical Evolution of Adult Patients with Nonsegmental Vitiligo

Dermatology ◽  
2021 ◽  
pp. 1-9
Author(s):  
María Luisa Peralta-Pedrero ◽  
Denisse Herrera-Bringas ◽  
Karla Samantha Torres-González ◽  
Martha Alejandra Morales-Sánchez ◽  
Fermín Jurado Santa-Cruz ◽  
...  
Keyword(s):  
Body Surface ◽  
Task Force ◽  
Intraclass Correlation ◽  
The Body ◽  
Response To Treatment ◽  
Similar Response ◽  
Clinical Evolution ◽  
Wide Range ◽  
Patient Reported ◽  
Extreme Groups

<b><i>Background:</i></b> Vitiligo has an unpredictable course and a variable response to treatment. Furthermore, the improvement of some vitiligo lesions cannot be considered a guarantee of a similar response to the other lesions. Instruments for patient-reported outcome measures (PROM) can be an alternative to measure complex constructions such as clinical evolution. <b><i>Objective:</i></b> The aim of this study was to validate a PROM that allows to measure the clinical evolution of patients with nonsegmental vitiligo in a simple but standardized way that serves to gather information for a better understanding of the disease. <b><i>Methods:</i></b> The instrument was created through expert consensus and patient participation. For the validation study, a prospective cohort design was performed. The body surface area affected was measured with the Vitiligo Extension Score (VES), the extension, the stage, and the spread by the evaluation of the Vitiligo European Task Force assessment (VETFa). Reliability was determined with test-retest, construct validity through hypothesis testing, discriminative capacity with extreme groups, and response capacity by comparing initial and final measurements. <b><i>Results:</i></b> Eighteen semi-structured interviews and 7 cognitive interviews were conducted, and 4 dermatologists were consulted. The instrument Clinical Evolution-Vitiligo (CV-6) was answered by 119 patients with a minimum of primary schooling. A wide range was observed in the affected body surface; incident and prevalent cases were included. The average time to answer the CV-6 was 3.08 ± 0.58 min. In the test-retest (<i>n</i> = 53), an intraclass correlation coefficient was obtained: 0.896 (95% CI 0.82–0.94; <i>p</i> &#x3c; 0.001). In extreme groups, the mean score was 2 (2–3) and 5 (4–6); <i>p</i> &#x3c; 0.001. The initial CV-6 score was different from the final one and the change was verified with VES and VETFa (<i>p</i> &#x3c; 0.05, <i>n</i> = 92). <b><i>Conclusions:</i></b> The CV-6 instrument allows patient collaboration, it is simple and brief, and it makes it easier for the doctor to focus attention on injuries that present changes at the time of medical consultation.

scholarly journals Hydromechanics of low-Reynolds-number flow. Part 2. Singularity method for Stokes flows

1975 ◽  
Vol 67 (4) ◽  
pp. 787-815 ◽  
Author(s):  
Allen T. Chwang ◽  
T. Yao-Tsu Wu
Keyword(s):  
Exact Solutions ◽  
Stokes Flow ◽  
Fundamental Solutions ◽  
The Body ◽  
Circular Cylinders ◽  
Geometrical Parameters ◽  
Flow Problems ◽  
Singularity Method ◽  
Wide Range ◽  
Body Shapes

The present study further explores the fundamental singular solutions for Stokes flow that can be useful for constructing solutions over a wide range of free-stream profiles and body shapes. The primary singularity is the Stokeslet, which is associated with a singular point force embedded in a Stokes flow. From its derivatives other fundamental singularities can be obtained, including rotlets, stresslets, potential doublets and higher-order poles derived from them. For treating interior Stokes-flow problems new fundamental solutions are introduced; they include the Stokeson and its derivatives, called the roton and stresson.These fundamental singularities are employed here to construct exact solutions to a number of exterior and interior Stokes-flow problems for several specific body shapes translating and rotating in a viscous fluid which may itself be providing a primary flow. The different primary flows considered here include the uniform stream, shear flows, parabolic profiles and extensional flows (hyper-bolic profiles), while the body shapes cover prolate spheroids, spheres and circular cylinders. The salient features of these exact solutions (all obtained in closed form) regarding the types of singularities required for the construction of a solution in each specific case, their distribution densities and the range of validity of the solution, which may depend on the characteristic Reynolds numbers and governing geometrical parameters, are discussed.

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