scholarly journals Determination of the Aspect-ratio Distribution of Gold Nanorods in a Colloidal Solution using UV-visible absorption spectroscopy

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Rahul Kumar ◽  
Leonardo Binetti ◽  
T. Hien Nguyen ◽  
Lourdes S. M. Alwis ◽  
Arti Agrawal ◽  
...  
Keyword(s):  
Colloidal Solution ◽  
Cost Effective ◽  
Colloidal Solutions ◽  
Electron Microscopic ◽  
Ratio Distribution ◽  
Visible Absorption ◽  
Aspect Ratios ◽  
Uv Visible ◽  
Bellman Principle

AbstractKnowledge of the distribution of the aspect ratios (ARs) in a chemically-synthesized colloidal solution of Gold Nano Rods (GNRs) is an important measure in determining the quality of synthesis, and consequently the performance of the GNRs generated for various applications. In this work, an algorithm has been developed based on the Bellman Principle of Optimality to readily determine the AR distribution of synthesized GNRs in colloidal solutions. This is achieved by theoretically fitting the longitudinal plasmon resonance of GNRs obtained by UV-visible spectroscopy. The AR distribution obtained from the use of the algorithm developed have shown good agreement with those theoretically generated one as well as with the previously reported results. After bench-marking, the algorithm has been applied to determine the mean and standard deviation of the AR distribution of two GNRs solutions synthesized and examined in this work. The comparison with experimentally derived results from the use of expensive Transmission Electron Microscopic images and Dynamic Light Scattering technique shows that the algorithm developed offers a fast and thus potentially cost-effective solution to determine the quality of the synthesized GNRs specifically needed for many potential applications for the advanced sensor systems.

scholarly journals Green Synthesis of Silver Nanoparticles from the Extracts of Fruit Peel of Citrus tangerina, Citrus sinensis, and Citrus limon for Antibacterial Activities

2021 ◽  
Vol 2021 ◽  
pp. 1-8
Author(s):  
Moira Carmalita Dharsika Niluxsshun ◽  
Koneswaran Masilamani ◽  
Umaramani Mathiventhan
Keyword(s):  
Silver Nanoparticles ◽  
Antibacterial Activity ◽  
Citrus Sinensis ◽  
Orange Peel ◽  
Cost Effective ◽  
Diffusion Method ◽  
Citrus Limon ◽  
Fruit Peel ◽  
Visible Absorption ◽  
Uv Visible

Wide application of nanoparticles motivates the need for synthesising them. Here, a nontoxic, eco-friendly, and cost-effective method has been established for the synthesis of silver nanoparticles using extracts of lemon peel (Citrus limon), green orange peel (Citrus sinensis), and orange peel (Citrus tangerina). The synthesised nanoparticles have been characterised using UV-visible absorptionspectroscopy, Fourier transform infrared spectroscopy, and transmission electron microscopy (TEM). The UV-visible absorption spectrum of these synthesised silver nanoparticles shows an absorption peak at around 440 nm. TEM images show different shaped particles with various sizes. Furthermore, the antibacterial activity of silver nanoparticles was appraised by a well-diffusion method and it was observed that the green synthesised silver nanoparticles have an effective antibacterial activity against Escherichia coli and Staphylococcus aureus. The outcome of this study could be beneficial for nanotechnology-based biomedical applications.

scholarly journals Presence of Yellow 6, an Artificial Colour Additive in Orange Juice

2012 ◽  
Vol 25 (1) ◽  
pp. 80-86 ◽  
Author(s):  
Abida Sultana ◽  
Mohammad S Haque ◽  
Mohammad Shoeb ◽  
M Saiful Islam ◽  
M Iqbal R Mamun ◽  
...  
Keyword(s):  
Adverse Effects ◽  
Orange Juice ◽  
Cost Effective ◽  
Chemical Society ◽  
Soft Drinks ◽  
Visible Absorption ◽  
Cost Effective Method ◽  
The World ◽  
Uv Visible ◽  
Color Additive

Soft drinks and orange juices are very popular all over the world including Bangladesh. Yellow 6 (Disodium 6-hydroxy-5-(4-sulfophenyl) azo-2-naphthalenesulfonate) was used in food and drinks as color additives earlier but due to its adverse effects on human health, yellow 6 has been banned in many countries. However, this harmful color additive yellow 6 is being used in commercial orange drinks in Bangladesh. Ten commercial brand yellow colored soft drinks and juices were analyzed to find out the presence of yellow 6. Juice prepared from fresh fruits was used as control. The UV-visible absorption maxima of yellow 6 is 429 nm. The amount of yellow 6 in commercial brands and fresh orange juices was determined by UV-visible spectrophotometer. Out of ten samples, seven juice samples were found to contain yellow 6 in the range of 0.83-1.66 mg/mL.   Fresh juice did not show any absorption at 429 nm. This is an easy and cost effective   method to assess the presence of yellow 6 in orange juice and the method can be used for other food stuffs. DOI: http://dx.doi.org/10.3329/jbcs.v25i1.11778 Journal of Bangladesh Chemical Society, Vol. 25(1), 80-86, 2012

Optimization of the processes of introducing nanosilver into the structure of chipboard as an absorbent of formaldehyde

2020 ◽  
Author(s):  
A.M. Yabbarova ◽  
◽  
E.I. Stenina ◽  
Keyword(s):  
Systematic Approach ◽  
Mechanical Characteristics ◽  
Colloidal Solution ◽  
Layer By Layer ◽  
Nanosized Particles ◽  
Particle Board ◽  
Colloidal Solutions ◽  
Properties Of Materials ◽  
Physical And Mechanical Characteristics

A promising direction in producing the special-purpose plates is to increase their physical and mechanical characteristics, reduce toxicity, and use highperformance equipment. The article analyzes the results of experiments to determine the physicomechanical parameters of particle board. Using a colloidal solution of nanosilver, the optimal models of layer-by-layer introduction of nanosilver into the structure of particle board (as a formaldehyde absorber) are determined. The use of colloidal solutions of nanosized particles of various metals significantly improves a number of operational and technological properties of materials that would raise the quality of life of people to a new health-saving level. The article is an overview based on the principles of a systematic approach to using the sound methods and techniques of scientific research and contevporary means of scientific investigation.

Synthesis of Cadmium and its Oxide Nanomaterials by Pulsed Laser Ablation in Aqueous Media

2008 ◽  
Vol 1074 ◽  
Author(s):  
Subhash Chandra Singh ◽  
Rajkumar Swarnkar ◽  
Ram Gopal
Keyword(s):  
Laser Ablation ◽  
Colloidal Solution ◽  
Aqueous Media ◽  
Pulsed Laser ◽  
Pulsed Laser Ablation ◽  
Distilled Water ◽  
Visible Absorption ◽  
Cadmium Metal ◽  
Uv Visible

ABSTRACTCadmium based oxide and hydroxide nanocomposites material is synthesized by pulsed laser ablation of cadmium metal in the double distilled water. A piece of cadmium metal, placed on the bottom of glass vessel containing double distilled water, was irradiated with 1064 nm of pulsed Nd:YAG laser operating at 35 mJ/pulse energy and 10 ns pulse width for 30 minutes. Colloidal solution of produced Nanoparticles is found stable for two days. Fine white colored powder is obtained after drying centrifuged solution. UV-visible absorption of colloidal solution, XRD, TGA, DTA and FTIR of the powder is used for the characterization of material. Possible mechanism of synthesis and hydroxide to oxide transition is discussed.

scholarly journals Structural, Phase Transition, Morphological, Optical and Dielectric Properties of Lead Free(1-x)(Na0.99K0.01)(Nb0.95Sb0.05)O3-xBaTiO3 Solid Solutions

2019 ◽  
Vol 8 (4S2) ◽  
pp. 879-882
Keyword(s):  
Solid Solutions ◽  
Structural Phase ◽  
Lead Free ◽  
X Ray Diffraction ◽  
Electron Microscopic ◽  
Visible Absorption ◽  
Maximum Dielectric Constant ◽  
Uv Visible ◽  
Sintering Method ◽  
Ceramic Solid Solution

In this work, lead free (1-x)(Na0.99K0.01)(Nb0.95Sb0.05)O3-xBaTiO3, where x=0.1, 0.2 ceramic solid solution systems were prepared via solid state sintering method. X-ray diffraction (XRD) reveals that the influence of Ba2+ on crystal structure of the NKNS-xBT (x=0.1, 0.2) solid solutions. PXRD analysis showed that Ba2+ addition into NKNS ceramics caused significant change in crystal symmetry from tetragonal to cubic. The surface morphology of the prepared ceramics were determined by scanning electron microscopic (SEM) measurements and revealed that the uniform distribution of grains. Energy band gap were determined by UV-visible absorption spectrophotometer. Dielectric measurements show the maximum dielectric constant (ε~3044) and temperature (Tm~120°C) at 1 kHz.

Low Temperature Synthesis of Elongated Triangular Bipyramidal ZnO Nanostructures for Photocatalytic Activity

2018 ◽  
Vol 52 ◽  
pp. 1-14
Author(s):  
Gurjinder Singh ◽  
Sudhakar Panday ◽  
Mohit Rawat ◽  
Deepak Kukkar ◽  
Sanjeev Kumar ◽  
...  
Keyword(s):  
Electron Microscope ◽  
Low Temperature ◽  
Photocatalytic Degradation ◽  
Low Temperature Synthesis ◽  
Temperature Synthesis ◽  
Visible Absorption ◽  
X Ray ◽  
Aspect Ratios ◽  
Potential Applicability ◽  
Uv Visible

The manuscript reports wet chemical assisted low temperature synthesis of CTAB stabilized elongated triangular bipyramidal shape nanostructures of ZnO for photocatalytic degradation of methyle blue (MB) and congo red (CR) dyes. Physiochemical characterization has been carried out by X-ray diffraction, scanning electron microscope, transmission electron microscope and UV-visible spectroscope. Pure wurtzite structure of ZnO with crystallite size ~56 nm has been confirmed from X-ray study. Well dispersed particles with elongated triangular bipyramidal morphology have been observed through SEM. Fine resolved particles with varied aspect ratios ~80 X 200 ± 10 nm have been depicted by TEM images. UV-visible absorption analysis confirms the energy band gap of 3.43 eV for synthesized ZnO particles. Molecular composition and functional groups of CTAB were confirmed by FTIR spectroscopy. The potential applicability of the particles for photocatalytic degradation of MB and CR as standard analytical dyes was studied. Time bound study under UV irradiated source depicted more than 95% degradation of both dyes in separate experiments.

A Preliminary Study on the Effect of Pandanus amaryllifolius Extract as Green Stabilizer to the Growth of Nanostructured ZnO

2020 ◽  
Vol 990 ◽  
pp. 277-282
Author(s):  
Rabiatuladawiyah Md Akhir ◽  
Siti Zulaikha Umbaidilah ◽  
Nurul Afaah Abdullah ◽  
Mohamad Rusop Mahmood ◽  
Zuraida Khusaimi
Keyword(s):  
Cost Effective ◽  
Hexagonal Wurtzite Structure ◽  
Zno Nanoparticle ◽  
X Ray Diffraction ◽  
Green Method ◽  
Visible Absorption ◽  
X Ray ◽  
Preliminary Study ◽  
Uv Visible ◽  
Average Size

Nanostructured zinc oxide (ZnO) were successfully prepared by using phyto assisted solution immersion process. ZnO were grown on a glass substrate coated with ZnO nanoparticle thin-film as seed layer at annealing temperature of 450°C. The fabricated nanostructured ZnO exhibit absorption at ∼375 nm as revealed from the UV-visible absorption spectrum, and it is comparable with ZnO nanostructured synthesized from hexamethylenetetramine (HMTA). X-ray diffraction (XRD) measurement revealed a sharp peak corresponding to the hexagonal wurtzite structure of nanostructured ZnO. Field emission scanning electron microscopy (FESEM) showed average size of ZnO at 24.15 nm slightly smaller compared to synthesized from HMTA; 30.54 nm. It should also be highlighted that the needs of using this alternative green method are due to the advantages of low working temperature and cost-effective, and with the least possible damage to the environment.

scholarly journals Biodegradation of Methyl Parathion Using Pseudomonas stutzeri (MTCC 2643)

2020 ◽  
Vol 2 (2) ◽  
pp. 19-33
Author(s):  
Archana S ◽  
Surendran A ◽  
Thatheyus AJ
Keyword(s):  
Bacterial Strain ◽  
Hplc Analysis ◽  
Methyl Parathion ◽  
Crop Protection ◽  
Pseudomonas Stutzeri ◽  
Cost Effective ◽  
Agricultural Fields ◽  
Microbial Remediation ◽  
Uv Visible

Pesticides applied in agricultural fields for crop protection result in the contamination of the environment. They also affect the flora and fauna as well as the quality of air, water and soil. Hence their remediation is of concern. Among different strategies available, microbial remediation is cost effective and ecofriendly. The present work is designed to test the efficiency of Pseudomonas stutzeri, a bacterial strain obtained from MTCC, IMTECH, Chandigarh, India. After treating with 50, 100, 150 and 200 ppm of methyl parathion, parameters like, orthophosphate released, pH and turbidity changes were monitored upto thirty hours. Degradation of 200 ppm concentration was confirmed by UV-Visible spectrophotometry and HPLC analysis. This strain effectively degraded methyl parathion and it can be used in the remediation of contaminated agricultural fields.

Convergent Beam Electron Diffraction

1978 ◽  
Vol 36 (3) ◽  
pp. 304-315
Author(s):  
G. Lehmpfuhl
Keyword(s):  
Electron Diffraction ◽  
Diffraction Pattern ◽  
Crystal Surface ◽  
Diffraction Spot ◽  
Crystal Thickness ◽  
Large Area ◽  
Electron Microscopic ◽  
Additional Information ◽  
Microscopic Investigations

Introduction In electron microscopic investigations of crystalline specimens the direct observation of the electron diffraction pattern gives additional information about the specimen. The quality of this information depends on the quality of the crystals or the crystal area contributing to the diffraction pattern. By selected area diffraction in a conventional electron microscope, specimen areas as small as 1 µ in diameter can be investigated. It is well known that crystal areas of that size which must be thin enough (in the order of 1000 Å) for electron microscopic investigations are normally somewhat distorted by bending, or they are not homogeneous. Furthermore, the crystal surface is not well defined over such a large area. These are facts which cause reduction of information in the diffraction pattern. The intensity of a diffraction spot, for example, depends on the crystal thickness. If the thickness is not uniform over the investigated area, one observes an averaged intensity, so that the intensity distribution in the diffraction pattern cannot be used for an analysis unless additional information is available.

Sign in / Sign up

Export Citation Format

Share Document