Double Distilled Deionized Water Research Articles

Wavelength Role in Synthesis and Study of the Structure of Silver Nanoparticles Prepared by Pulsing Laser Ablation in Liquid

Silver nanoparticles (NPs) were made using double-distilled deionized water (DDDW) and pulsing laser ablation in liquid (PLAL) with Q-switched technology (Nd:YAG) laser (energy: 80[Formula: see text]mJ, number of pulses: 500) at various wavelengths (1064[Formula: see text]nm and 532[Formula: see text]nm). The surface plasmon extinction (SPE) peaks were used to measure the PLAL process’s formation quality. The SPE spectra showed a single sharp peak at about 400[Formula: see text]nm, suggesting that pure and spherical silver was produced. The formation of silver particles was verified by UV–vis spectrophotometer absorption results. According to the AFM findings, as the wavelength of the laser beam used for preparation increased, the average grain size of the particles decreased. Finally, SEM images pointing to the produced silver nanoparticles spherical in their shape, were shown. The elemental analysis and chemical characterization with energy-dispersive X-ray spectroscopy (EDX) were performed on the produced samples. This confirmed the high purity of the obtained samples and the existence of Ag NPs.

Synthesis Conditions Of Au Core@ Ag Shell System by Laser Ablation in Distilled Water By Using Different Wavelengths “(1064, 532, 355)”nm

In this study, an easy and a rapid method has been used to prepare nanoparticles employing the laser ablation technique in Double Distilled Deionized Water (DDDW). Lasers with three different have been used. The laser ablation of a (Au core @ Ag shell) system shows the best ablation at wavelengths of 1064 and 355 nm in DDDW solution with resulting Grain size less than (20 nm).This is the best result for obtaining the size near Quantum Dot (Q.D.) of the Ag @ Au NPS system. The TEM, AFM and statistical distribution of Grain size have been used to analysis morphological properties. The absorption peak shows IR shift for Au @ Ag system, that leads to growth large grains. This indicates that Ag-shell more effective than Au-core at (532,355) nm wavelengths. Some of the optical parameters, such as refractive index (n) and extinction coefficient (k), have been calculated for the prepared nanoparticles collide. TEM shows the formation (Core -Shell) clearly, and the form of NPs can almost have a spherical shape with size < 20 nm. The gold (Au-shell) is more effective than Ag-core.The colloidal nanoparticles have been used as in biological applications to kill or inhibit E. coli and Staph bacteria.

Preparation and characterization of colloidal CdTe nanoparticles by laser ablation in liquids

Nanoparticles generation by laser ablation of a solid target in a liquid environment is an easy method. Cadmium Telluride (CdTe) colloidal nanoparticles have been synthesized by laser ablation Nd:YAG with wavelengths of 1064nm and double frequency at 532 nm, number of pulses 50 pulses, with pulse energy= 620mJ, 700mJ of a solid target CdTe is immersed in double distilled deionized water (DDIW) and in methanol liquid. Influences of the laser energy and different solutions on the formation and optical characterization of the CdTe nanoparticles have been studied using atomic force microscope (AFM) and the UV-Vis absorption. As a results, it leads to the absorbance in UV-Vis spectra of samples prepared in water at laser wavelength of 532nm is lower than the absorbance of 1064nm at same laser energy. AFM images show that CdTe NPs have spherical shape in nanometer size.

Effect of laser energy and pulses on size and concentration of gold nanoparticles in DDDW by LALP method

The size and the concentration of the gold nanoparticles (GNPs)synthesized in double distilled deionized water (DDDW) have beenfound to be affected by the laser energy and the number of pulses.The absorption spectra of the nanoparticles DDDW, and thesurface plasmon resonance (SPR) peaks were measured, and found tobe located between (509 and 524)nm using the UV- Visspectrophotometer. SPR calculations, images of transmissionelectron microscope, and dynamic light scattering (DLS) methodwere used to determine the size of GNPs, which found to be rangedbetween (3.5 and 27) nm. The concentrations of GNPs in colloidalsolutions found to be ranged between (37 and 142) ppm, andmeasured by atomic absorption spectroscopy (AAS).

Organic vapor sensor using photoluminescence of laser ablated gold nanoparticles on porous silicon

Gold nanoparticles (AuNPs) were prepared by laser ablation technique of gold target submerged in double distilled deionized water (DDDW) at room temperature. AuNPs are incorporated into porous silicon (PS) that was prepared using the electrochemical etching technique. In this study, the influence of gold colloids on PS characteristics has been investigated. The variation of the surface roughness and morphology after noble metal modification was revealed by Atomic Force Microscopy (AFM), while, Fourier Transform Infrared (FTIR) characterization techniques proved the oxidation of porous silicon substrate leading to the passivation of the surface states. It was also observed that the reflectivity was decreased due to the deposition process depending on the size and the quantity of gold colloid solution. These are attributed to metal nanoparticles (MNPs) with narrow particle-size distribution uniformly coated on the surface, thus, the substrate efficiency is strictly related to their dispersion, which could yield to local surface Plasmon (LSP).The photoluminescence (PL) spectroscopy revealed that the intensity is strongly depend on AuNPs deposition and effected by organic vapor after deposition on PS.

Surface Modification of Red Brass Alloy by Using Laser Technique

Laser shock processing technique was performed on red brass alloy type C83300 specimens for the purpose ofstudy its effect on the mechanical properties such as micro-hardness and surface roughness. LSP experimental setup system involved Q-switched Nd:YaG laser of wavelength of 1064nm and 10 ns laser pulse . Double distilled deionized water (DDDW) is used as the transparent confining layer. The effects of the LSP parameters as laser pulse energy, number of laser pulses and thickness of confinement layer on the surface micro-hardness, and surface roughness were investigated. The experimental results show that, the surface roughness and micro-hardness values increased when the laser parameters (mentioned above) have been increased and the maximum value of micro-hardness generated near the surface due to LSP. The optimum thickness of DDDW layer was 4mm. After this thickness (4mm) ,the results of microhardness and surface roughness are reduced due to the absorption of laser pulse energy by the confinement layer .

Wet Chemically Synthesized CuO Bipods and their Optical Properties.

Metal oxide nanostructures are being investigated widely due to their strong optical absorption, efficient photoluminescence, abundant of availability and structural stability which lead them as a possible substitute of Si based solar cells and many optoelectronic and sensor devices. Due to their non-toxic nature they are supposed to be promising materials for drug delivery and medical research. Among several metal oxides, cupric oxide (CuO) is being investigated nowadays due to their high transparency and visible luminescence. It is a p-type semiconductor of band gap varying from 1.3 eV to 2.1 eV depending of the structure and process of fabrication. This low band gap of CuO nanostructures leads its application in photoconductive and photothermal applications. This leads rigorous investigations on CuO nanostructures. A simple wet chemical methods has been used to synthesize CuO bipods. Predetermined amount of Copper sulphate penta-hydrate (CuSO4, 5H2O) was dissolved in double distilled de-ionized water to prepare 0.5 M solution. Predetermined amount of Lithium hydroxide (LiOH) was dissolved in de-ionized water to prepare 1 M solution. Under rigorous magnetic stirring of the LiOH solution CuSO4 solution was added drop by drop for five minutes and the stirring was maintained for 2 hours at room temperature (30°C). After the reaction a white precipitate was observed at the bottom of the flask. This solution was then aged for 24 hours. The color of the precipitate solution was turned into grey. The precipitate was filtered and subsequently washed with distilled de-ionized water thrice for the removal of unreacted salts if any. The precipitate was then dried in an ordinary furnace at 150°C for further characterization. X-ray diffraction data confirmed the formation of well crystalline CuO having monoclinic unit cell structure. The crystallite size was ~ 12 nm as calculated from the XRD pattern. Transmission electron microscope images revealed that the bipod-like structure is composed of several crystallites. The lengths of the bipods are ~ 300 nm with a waist size ~ 100 nm. The UV-visible spectroscopic data revealed a strong absorption at ~ 376 nm and the band gap was calculated to be 2.51 eV. FTIR spectrum revealed the existence of only Cu=O bonds. In the Raman shift data two strong peaks were found at 273 cm-1, and 608 cm-1 that owe to the Ag mode and Bg mode respectively. Room temperature photoluminescence spectroscopy revealed that the CuO nanoparticles exhibit broad strong emission at ~ 472 nm. After decomposing we observed three peaks at 436, 469 and 495 nm. The emission peak at 469 nm arises due to near band edge transition. The emission peak at 495 nm arises due to shallow level defect states related transitions. In conclusion, we have fabricated CuO nano-bipods using a simple wet chemical method. XRD pattern indicates the formation of well crystalline and pure CuO without any impurity. The nano-bipods exhibit sharp absorption peak at ~ 376 nm with optical band gap energy of 2.51 eV. FTIR spectrum and Raman shift data confirms the formation of CuO with the presence of Ag mode (273 cm-1) and Bg mode (608 cm-1). The fabricated CuO nano-bipods exhibit strong PL emission at 469 nm owing to the recombination of free excitons at the absorption band edge in the UV region associated with other low intense deep level emission. Few relevant patents to the topic have been reviewed and cited.

Adsorption Studies with Arsenic onto Ferric Hydroxide Gel in a Non-oxidizing Environment: the Effect of Co-occurring Solutes and Speciation

Abstract Groundwater arsenic contamination has emerged as a major health threat to millions of people around the world. Studying the sorption process of As(III) and As(V) onto ferric hydroxide gel is important to understand the mobilization of arsenic under nonoxidizing conditions. Most of the previous adsorption studies were limited to single element or multi-element equilibrium in synthetic water. To investigate the effect of matrix and speciation in real groundwater systems, adsorption tests with added As(III) and As(V) separately and in mixture were conducted in both double-distilled deionized water (DDDW) and As-safe (&amp;lt;3 µg L-1) tubewell water. In DDDW, the As(III)/As(V) ratio in the mixture strongly influenced the sorption behaviour by shifting the adsorption edge and also the efficiency. For As(III) and As(V) mixture in 1:1 proportions in tubewell water, the adsorption of both the species decreased up to pH 8; in the alkaline ranges the adsorption extent was marginally increased in comparison to that in DDDW. When As(III):As(V) was added in 3:1 proportions in tubewell water, the adsorption of both was enhanced in alkaline ranges compared to that in DDDW. When As(V) was predominant [As(V):As(III) = 3:1] in tubewell water, no significant changes were observed for As(V), though adsorption of As(III) was notably retarded. The statistical analysis of the results indicates the concentration ratio of As species in the system has a definite impact on adsorption behaviour onto ferric hydroxide gel.

Effects of blanching and soaking on some physical characteristics of grass pea (&lt;i&gt;Lathyrus sativus&lt;/i&gt;)

Lathyrus sativus , containing a lathyritic principle, called β-ODAP (β-N-Oxalyl-L- α, β-diaminopropionic acid), is widely grown and consumed in Ethiopia. It is a hardy crop grown under various agro-ecological situations. The major drawback in the use of the legume is the fact that the seeds, in common with other legumes, are not easily rehydrated, are difficult to cook, the seed coat is difficult to remove and long cooking time is required by traditional processing methods for tenderization. In this study, the effect of processing methods like blanching, soaking and cooking on water absorption, leached solids, swelling power, cooking time and sensory qualities of grass pea seeds were investigated. The soaking solutions used were mixed with salt solution, wood ash solution and double distilled de-ionized water. Blanching significantly (p Keywords : blanching, cooking, Lathyrus sativus , soaking African Journal of Food, Agriculture, Nutrition and Development Vol. 6(1) 2006

Dissolution behavior of plasma-sprayed hydroxyapatite coatings.

The long-term stability of plasma-sprayed hydroxyapatite coatings is influenced by the dissolution behavior of the coating in in vivo conditions. Plasma-spraying generates a mixture of phases and this study has focused on how the balance of phases affects the in vitro dissolution behavior of the coatings in double distilled-deionized water and in tris-buffer solutions. The pH changes in double distilled-deionized water were monitored, whilst the pH value was maintained at 7.25 for the tris-buffer solution at 37 degrees C with 5% CO2 atmosphere. The phosphate and calcium ions released were measured using UV-Visible Spectrophotometer and Atomic Absorption Spectroscopy respectively. Changes in crystal and surface topology were also studied. The results indicate that the dissolution behavior of the coatings depends on several factors. The rate of release of phosphate ions was found to increase significantly for the tris-buffer solution compared to the deionized water, indicating that the presence of electrolyte constituents affects the dissolution behavior of the coatings. The Ca/P ratio in the tris-buffer solution is approximately three. Increases in the level of crystallinity of the coatings significantly decreased the dissolution rate and hence, the amount of phosphate ions released. The higher the percentage of crystallinity, the higher the stability of the coating under in vitro conditions.

Storm simulation experiments on soil monoliths from a small moorland catchment in south west Scotland—soil leachate composition and implications for streamwater chemistry

Abstract Intact and partial soil cores from a small catchment (Dargall Lane) of the Galloway Hills of southwest Scotland were treated in the laboratory with simulated precipitation using double‐distilled, deionized water (DDDW) as a “control rain”, and artificial rain of composition similar to local bulk atmospheric deposition. The leachate chemistry shows that periods of drying and re‐wetting of the acidic, organic‐rich soils of this typical moorland catchment, may produce large flushes of cations (including Al) and anions. This means that increased element mobility can be caused by processes other than external hydrogen loadings.