scholarly journals Direct and selective synthesis of a wide range of carbon nanomaterials by CVD at CMOS compatible temperatures

2014 ◽  
Author(s):  
Irene Taurino ◽  
Arnaud Magrez ◽  
Laszlo Forro ◽  
Giovanni De Micheli ◽  
Sandro Carrara
Keyword(s):  
Carbon Nanomaterials ◽  
Selective Synthesis ◽  
Wide Range ◽  
Cmos Compatible

scholarly journals Photonic Microwave and RF Channelizers using CMOS Compatible Kerr Micro-combs

2021 ◽  
Author(s):  
Mengxi Tan ◽  
xingyuan xu ◽  
David Moss
Keyword(s):  
Signal Detection ◽  
Ring Resonator ◽  
Microwave Signal ◽  
Optical Frequency ◽  
Potential Cost ◽  
Wide Range ◽  
Integrated Optical ◽  
Cmos Compatible ◽  
Reduced Complexity ◽  
Resonator Filters

Abstract We report broadband RF channelizers based on integrated optical frequency Kerr micro-combs combined with passive micro-ring resonator filters, with microcombs having channel spacings of 200GHz and 49GHz. This approach to realizing RF channelizers offers reduced complexity, size, and potential cost for a wide range of applications to microwave signal detection.

scholarly journals Carbon Nanomaterials as Versatile Platforms for Biosensing Applications

Micromachines ◽  
2020 ◽  
Vol 11 (9) ◽  
pp. 814
Author(s):  
Hye Suk Hwang ◽  
Jae Won Jeong ◽  
Yoong Ahm Kim ◽  
Mincheol Chang
Keyword(s):  
Metallic Nanoparticles ◽  
Carbon Nanomaterials ◽  
Measuring System ◽  
Mechanical And Electrical Properties ◽  
Target Analytes ◽  
Wide Range ◽  
Biological Recognition ◽  
Simple Molecules ◽  
Living Organisms ◽  
Biological Analytes

A biosensor is defined as a measuring system that includes a biological receptor unit with distinctive specificities toward target analytes. Such analytes include a wide range of biological origins such as DNAs of bacteria or viruses, or proteins generated from an immune system of infected or contaminated living organisms. They further include simple molecules such as glucose, ions, and vitamins. One of the major challenges in biosensor development is achieving efficient signal capture of biological recognition-transduction events. Carbon nanomaterials (CNs) are promising candidates to improve the sensitivity of biosensors while attaining low detection limits owing to their capability of immobilizing large quantities of bioreceptor units at a reduced volume, and they can also act as a transduction element. In addition, CNs can be adapted to functionalization and conjugation with organic compounds or metallic nanoparticles; the creation of surface functional groups offers new properties (e.g., physical, chemical, mechanical, electrical, and optical properties) to the nanomaterials. Because of these intriguing features, CNs have been extensively employed in biosensor applications. In particular, carbon nanotubes (CNTs), nanodiamonds, graphene, and fullerenes serve as scaffolds for the immobilization of biomolecules at their surface and are also used as transducers for the conversion of signals associated with the recognition of biological analytes. Herein, we provide a comprehensive review on the synthesis of CNs and their potential application to biosensors. In addition, we discuss the efforts to improve the mechanical and electrical properties of biosensors by combining different CNs.

scholarly journals A CMOS Compatible Pyroelectric Mid-Infrared Detector Based on Aluminium Nitride

Sensors ◽  
2019 ◽  
Vol 19 (11) ◽  
pp. 2513 ◽  
Author(s):  
Christian Ranacher ◽  
Cristina Consani ◽  
Andreas Tortschanoff ◽  
Lukas Rauter ◽  
Dominik Holzmann ◽  
...  
Keyword(s):  
Infrared Detector ◽  
Aluminium Nitride ◽  
Co2 Absorption ◽  
Absorption Region ◽  
Mid Infrared ◽  
Infrared Spectral Range ◽  
Wide Range ◽  
Infrared Spectral ◽  
Pyroelectric Material ◽  
Cmos Compatible

The detection of infrared radiation is of great interest for a wide range of applications, such as absorption sensing in the infrared spectral range. In this work, we present a CMOS compatible pyroelectric detector which was devised as a mid-infrared detector, comprising aluminium nitride (AlN) as the pyroelectric material and fabricated using semiconductor mass fabrication processes. To ensure thermal decoupling of the detector, the detectors are realized on a Si3N4/SiO2 membrane. The detectors have been tested at a wavelength close to the CO2 absorption region in the mid-infrared. Devices with various detector and membrane sizes were fabricated and the influence of these dimensions on the performance was investigated. The noise equivalent power of the first demonstrator devices connected to a readout circuit was measured to be as low as 5.3 × 10 − 9 W / Hz .

Neuronal dynamics in HfOx/AlOy-based homeothermic synaptic memristors with low-power and homogeneous resistive switching

Nanoscale ◽  
2019 ◽  
Vol 11 (1) ◽  
pp. 237-245 ◽  
Author(s):  
Sungjun Kim ◽  
Jia Chen ◽  
Ying-Chen Chen ◽  
Min-Hwi Kim ◽  
Hyungjin Kim ◽  
...  
Keyword(s):  
Low Power ◽  
Resistive Switching ◽  
Neuronal Dynamics ◽  
Wide Range ◽  
Cmos Compatible

Homeothermic synaptic behaviors with a wide range of temperature were demonstrated in CMOS-compatible HfOx/AlOy memristors.

Principles for assessing the genotoxicity of carbon nanomaterials in vitro (on the example of carbon nanotubes) (literature review)

2021 ◽  
Vol 29 (6) ◽  
pp. 16-23
Author(s):  
Gulnaz Faezovna Gabidinova ◽  
Gyuzel Abdulkhalimovna Timerbulatova ◽  
Liliya Minvagizovna Fatkhutdinova
Keyword(s):  
Carbon Nanomaterials ◽  
Physicochemical Characterization ◽  
Gene Mutations ◽  
Micronucleus Assay ◽  
Bibliographic Databases ◽  
Chromosomal Damage ◽  
Colorimetric Test ◽  
Wide Range ◽  
Dna Strand

Introduction. Genotoxicity of nanomaterials (NM) is becoming a major concern when investigating new NM for their safety. Each mutagen is considered to be potentially carcinogenic, therefore a genotoxicity assessment is necessary. However, a clear strategy for assessing the genotoxic effect of NM has not yet been developed. Material and methods. The material for the analysis have included literature sources from the bibliographic databases PubMed, Scopus, RSCI. Results. Physicochemical characterization of NM is carried out using high-resolution microscopic and light scattering methods. Before testing for genotoxicity, it is necessary to know the cytotoxicity of the tested NM in order to select the appropriate concentration range. The most important and significant tests are based on the cell viability. MTT assay is a colorimetric test that evaluates the metabolic activity of cells. In addition, viability can be determined using microscopy, flow cytometry, determination of lactate dehydrogenase. Genotoxicity evaluation can be carried out only after the preliminary steps. The strategy should include genotoxicity endpoints: DNA damage, gene mutations, chromosomal damage. The in vitro mammalian gene mutation test, usually performed using mouse lymphoma cells, detects a wide range of genetic damage, including gene deletions. The most common test for detecting chromosomal damage is an in vitro micronucleus assay. DNA strand breaks are most often assessed using the comet DNA assay. Conclusion. Compulsory stages in the study of the genotoxicity of nanomaterials should be preliminary studies, including physicochemical characterization and assessment of cytotoxicity, as well as the study of the endpoints of genotoxicity and potential mechanisms.

scholarly journals Selective Synthesis of Ortho-substituted 3-Cyclohexyl-2-phenyl-1,3-thiazolidin-4-one Sulfoxides and Sulfones by S-Oxidation with Oxone

2015 ◽  
Vol 7 (2) ◽  
pp. 73 ◽  
Author(s):  
Kevin Cannon ◽  
Deepa Gandla ◽  
Samantha Lauro ◽  
Lee Silverberg ◽  
John Tierney ◽  
...  
Keyword(s):  
Biological Activity ◽  
High Temperature ◽  
Aromatic Ring ◽  
Selective Oxidation ◽  
1H Nmr ◽  
Room Temperature ◽  
Selective Synthesis ◽  
Wide Range ◽  
Synthetic Routes ◽  
S Oxidation

1,3-thiazolidin-4-ones, also known as thiazolidin-4-ones, are known to have a very wide range of biological activity. The corresponding S-oxides may show enhanced activity, and therefore viable synthetic routes to these S-oxides are required. S-oxidation of 3-cyclohexyl-2-phenyl-1,3-thiazolidin-4-ones with Oxone® was investigated. For all compounds evaluated, selective oxidation to the sulfoxide was realized using 3 equivalents of Oxone® at room temperature. Alternatively, the sulfone was prepared selectively at high temperature by increasing the equivalents of Oxone® used; the extent of this selectivity was affected by the substituent of the aromatic ring. In those cases in which the reaction produced a mixture of the sulfoxide and sulfone, the ratio of the products was quantified by 1H NMR.

scholarly journals Aqueous dispersions of oligomer-grafted carbon nanomaterials with controlled surface charge and minimal framework damage

2014 ◽  
Vol 173 ◽  
pp. 273-285 ◽  
Author(s):  
Sheng Hu ◽  
Shu Chen ◽  
Robert Menzel ◽  
Angela D. Goode ◽  
Mary P. Ryan ◽  
...  
Keyword(s):  
Surface Charge ◽  
Carbon Nanomaterials ◽  
Water Solubility ◽  
Thermochemical Treatment ◽  
High Water ◽  
Ionic Character ◽  
Gravimetric Analysis ◽  
Physiochemical Properties ◽  
Toxicological Effects ◽  
Wide Range

Functionalised carbon nanomaterials (CNMs), with an undamaged carbon framework and controlled physiochemical properties, are desirable for a wide range of scientific studies and commercial applications. The use of a thermochemical grafting approach provides a versatile means to functionalise both multi-walled carbon nanotubes (MWCNTs) and carbon black (CB) nanoparticles without altering their inherent structures. The functionalisation process was investigated by employing various types of grafting monomers; to improve water solubility, reagents were chosen that introduced an ionic character either intrinsically or after further chemical reactions. The degree of grafting for both MWCNTs and CB ranged from 3–27 wt%, as established by thermal gravimetric analysis (TGA). Raman spectroscopy confirmed that the structural framework of the MWCNTs was unaffected by the thermochemical treatment. The effectiveness of the surface modification was demonstrated by significantly improved dispersibility and stability in water, and further quantified by zeta-potential analysis. The concentration of stable, individualised and grafted MWCNTs in water ranged from ∼30 to 80 μg mL−1after centrifugation at 10 000 g for 15 min, whereas functionalised CB in water showed improved dispersibility up to ∼460 μg mL−1. The successful preparation of structurally identical but differently functionalised nanoparticle panels, with high water compatibility and minimal framework damage, is useful for controlled experiments. For example, they can be used to explore the relationship between toxicological effects and specific physiochemical properties, such as surface charge and geometry.

A Selective and Versatile Synthesis of Substituted Chromones via Addition of Phenols to Dimethyl Acetylenedicarboxylate

1995 ◽  
Vol 48 (3) ◽  
pp. 677 ◽  
Author(s):  
MJ Stoermer ◽  
DP Fairlie
Keyword(s):  
Functional Groups ◽  
Addition Reaction ◽  
Initial Step ◽  
High Yield ◽  
Selective Synthesis ◽  
Dimethyl Acetylenedicarboxylate ◽  
Substituted Phenols ◽  
Valuable Component ◽  
Mild Conditions ◽  
Wide Range

Despite many published syntheses of chromones, none has been reported to be both selective for chromones and tolerant of ring substitution. The addition of substituted phenols to dimethyl acetylenedicarboxylate is now reported as a versatile high yield initial step in a simple three-step synthesis of chromone 2-carboxylic acids. Triethylamine being used to deprotonate the substituted phenol, the addition to dimethyl acetylenedicarboxylate proceeds under mild conditions and tolerates a wide range of functional groups on the phenol. Although not stereoselective, both fumarate and maleate aryloxy products of this addition can then be cyclized, according to a known method, to chromones without contamination by isomeric coumarins. Thus the addition reaction is a valuable component of a versatile and selective synthesis of substituted chromones.

scholarly journals Silicone Rubber Composites Reinforced by Carbon Nanofillers and Their Hybrids for Various Applications: A Review

Polymers ◽  
2021 ◽  
Vol 13 (14) ◽  
pp. 2322
Author(s):  
Vineet Kumar ◽  
Md Najib Alam ◽  
Amutheesan Manikkavel ◽  
Minseok Song ◽  
Dong-Joo Lee ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Electrical Properties ◽  
Silicone Rubber ◽  
Carbon Nanomaterials ◽  
Research Area ◽  
Rubber Matrix ◽  
Strain Sensing ◽  
Rubber Composites ◽  
Wide Range ◽  
Carbon Nanofillers

Without fillers, rubber types such as silicone rubber exhibit poor mechanical, thermal, and electrical properties. Carbon black (CB) is traditionally used as a filler in the rubber matrix to improve its properties, but a high content (nearly 60 per hundred parts of rubber (phr)) is required. However, this high content of CB often alters the viscoelastic properties of the rubber composite. Thus, nowadays, nanofillers such as graphene (GE) and carbon nanotubes (CNTs) are used, which provide significant improvements to the properties of composites at as low as 2–3 phr. Nanofillers are classified as those fillers consisting of at least one dimension below 100 nanometers (nm). In the present review paper, nanofillers based on carbon nanomaterials such as GE, CNT, and CB are explored in terms of how they improve the properties of rubber composites. These nanofillers can significantly improve the properties of silicone rubber (SR) nanocomposites and have been useful for a wide range of applications, such as strain sensing. Therefore, carbon-nanofiller-reinforced SRs are reviewed here, along with advancements in this research area. The microstructures, defect densities, and crystal structures of different carbon nanofillers for SR nanocomposites are characterized, and their processing and dispersion are described. The dispersion of the rubber composites was reported through atomic force microscopy (AFM), transmission electron microscopy (TEM), and scanning electron microscopy (SEM). The effect of these nanofillers on the mechanical (compressive modulus, tensile strength, fracture strain, Young’s modulus, glass transition), thermal (thermal conductivity), and electrical properties (electrical conductivity) of SR nanocomposites is also discussed. Finally, the application of the improved SR nanocomposites as strain sensors according to their filler structure and concentration is discussed. This detailed review clearly shows the dependency of SR nanocomposite properties on the characteristics of the carbon nanofillers.

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