1: Magnetic Particles: Preparation, Properties and Applications: M. Ozaki. 2: Maghemite (gamma-Fe2O3): A Versatile Magnetic Colloidal Material C.J. Serna, M.P. Morales. 3: Dynamics of Adsorption and Oxidation of Organic Molecules on Illuminated Titanium Dioxide Particles Immersed in Water M.A. Blesa, R.J. Candal, S.A. Bilmes. 4: Colloidal Aggregation in Two-Dimensions A. Moncho-Jorda, F. Martinez-Lopez, M.A. Cabrerizo-Vilchez, R. Hidalgo Alvarez, M. Quesada-PMerez. 5: Kinetics of Particle and Protein Adsorption Z. Adamczyk.

Surface and Colloid Science

(1976). Nuclear Tracks in Solids (Principles and Applications) Nuclear Technology: Vol. 30, No. 1, pp. 91-92.

Nuclear Tracks in Solids (Principles and Applications)

Author(s): Chen, Fanqing; Gerion, Daniele | Abstract: One of the biggest challenges in cell biology is the imaging of living cells. For this purpose, the most commonly used visualization tool is fluorescent markers. However, conventional labels, such as organic fluorescent dyes or green fluorescent proteins (GFP), lack the photostability to allow the tracking of cellular events that happen over minutes to days. In addition, they are either toxic to cells (dyes), or difficult to construct and manipulate (GFP). We report here the use of a new class of fluorescent labels, silanized CdSe/ZnS nanocrystal-peptide conjugates, for imaging the nuclei of living cells. CdSe/ZnS nanocrystals, or so called quantum dots (qdots), are extremely photostable, and have been used extensively in cellular imaging of fixed cells. However, most of the studies about living cells so far have been concerned only with particle entry into the cytoplasm or the localization of receptors on the cell membrane. Specific targeting of qdots to the nucleus of living cells has not been reported in previous studies, due to the lack of a targeting mechanism and proper particle size. Here we demonstrate for the first time the construction of a CdSe/ZnS nanocrystal-peptide conjugate that carries the SV40 large T antigen nuclear localization signal (NLS), and the transfection of the complex into living cells. By a novel adaptation of commonly used cell transfection techniques for qdots, we were able to introduce and retain the NLS-qdots conjugate in living cells for up to a week without detectable negative cellular effects. Moreover, we can visualize the movement of the CdSe/ZnS nanocrystal-peptide conjugates from cytoplasm to the nucleus, and the accumulation of the complex in the cell nucleus, over a long observation time period. This report opens the door for using qdots to visualize long-term biological events that happen in the cell nucleus, and provides a new nontoxic, long-term imaging platform for cell nuclear processes.

/pdf/fluorescent-cdse-zns-nanocrystal-peptide-conjugates-for-long-i96546wo0h.pdf

Fluorescent CdSe/ZnS nanocrystal-peptide conjugates for long-term, nontoxic imaging and

2D Black Phosphorus–Based Biomedical Applications

Ammonia gas sensors: A comprehensive review.

Zinc oxide (ZnO) nanoparticles have been synthesized by co-precipitation method. The structural properties like average crystallite size, lattice parameters, volume of unit cell, and X-ray density were studied by XRD. The crystallite size was measured by using Scherrer formula. It was observed that the average crystallite size increased with the increase of annealing temperature. Morphology of the synthesized oxides was investigated by SEM. The harmful constituents like organic compounds have been removed from waste water that is toxicant. Metal oxide semiconductors had shown good photocatalytic activity to degrade harmful organics into less harmful molecules under light-illumination. In this regard the dye (Rhodamine B) was degraded with increasing exposure time of UV radiations. Almost 60% dye degradation was observed in 150 min. The ZnO was also employed as an active anti-microbial nanomaterial on the growth of C. coli. A 15 μg of ZnO nanoparticles liquefied in 1 mL of dimethyl sulfoxide revealed outstanding 95.04 ± 1.37 % inhibition activities against growth of C. coli.

Effect of ZnO on Photocatalytic Degradation of Rh B and Its Inhibition Activity for C. coli Bacteria

In the biological environment, the fate of nanomaterials characterizes as critical matter, which regulates environmental effects and associated hazards for humans. Understanding of the nanoparticle’s degradation, transformations and persistence may predict these risks. Safely designed inorganic nanomaterials are being focused for therapy; yet, fundamental processing in the biological environment and physical properties have not been assessed thoroughly. In this research work, bare, polyethylene glycol and citrate-coated cobalt ferrite nanoparticles (NPs) are prepared through modified chemical coprecipitation method. Structural, elemental, magnetic and morphological analysis of synthesized samples are performed through XRD, EDX, FTIR, VSM, SEM and TEM. XRD confirms the cubic structure of CoFe2O4 with crystallite size 25.75 nm. SEM and TEM confirm the formation of faceted cube-like morphology. For in vivo toxicity studies, a single dose of bare and coated cobalt ferrite NPs are intraperitoneally administrated in healthy albino rats. The degradation effects are studied through optical follow-up, by introducing bare and coated NPs in lysosomal-like media where changes in behavior are linked with transformations in vivo. Transfer of degraded ions of cobalt ferrite NPs into apoferritin are also evaluated. Apoferritin studies reveal partial filling of protein with cobalt ions from cobalt ferrite NPs.

Functionalized cobalt ferrite cubes: toxicity, interactions and mineralization into ferritin proteins

Laser ablation propulsion is a form of beam-powered propulsion in which a pulsed laser ablates a target material thus producing thrust. We report in this work the measurements of various parameters related to laser-induced micropropulsion in toluene diisocyanate-based polyurethane polymer, aluminum and Co–Ni ferrite. The targets were irradiated by a Q-switched pulsed Nd–YAG laser at 1064 nm (pulse duration 5 ns) under atmospheric conditions. A contact-free optical triangulation method was used to measure the laser ablation induced thrust in the samples. The measurements and calculations depict that Co–Ni ferrite is better in terms of critical propulsion parameters C
 m and I
 sp. It has been observed that the propulsion parameters depend on the energy per pulse of the incident laser beam.

Measurement of ablative laser propulsion parameters for aluminum, Co―Ni ferrite and polyurethane polymer

We report the spectroscopic studies of the Kohl plasma produced in air at atmospheric pressure by Laser Induced Breakdown Spectroscopy (LIBS) and Atomic Absorption Spectroscopy (AAS) techniques. The plasma has been produce using Q-switched Nd:YAG laser at Second Harmonic Generation SHG (532 nm), with laser irradiance of 4 × 1010 W/cm2, 10 Hz repetition rate and 5ns pulse duration. From the spectroscopic analysis of the registered spectrum, we have detected the presence of Pb, C, Ca, Cr, Fe, Ba, Zn, Hg, Na and H. The electron temperature has been determined from the intensity ratio of the two transition lines of Pb– I, 368.34 nm and 373.99 nm, whereas the electron number density has been estimated from the Stark broadening profile of the H α line at 656.28 nm. It has been noticed that the maximum value of the electron temperature and electron number density at the initial stage of the plasma. The electron temperature varies as (15500–11600) K and the number density varies as (2.06 × 1017–3.62 × 1016) cm−3 with the delay time of (1-6) μs.

Elemental Analysis of Kohl Using Laser Ablation and Atomic Absorption Spectroscopy (AAS) techniques

Polluted water is causing serious health problems especially in the rural areas of Pakistan. People have limited access to safe water supply and many diseases like diarrhea and gastrointestinal diseases are transmitted by consumption of polluted water. We have investigated the potential of using solar energy to pasteurize water. Low cost indigenously available materials have been utilized to design and fabricate a solar box type pasteurizer having a capacity of three liters. The performance study of the pasteurizer was performed during the month of May 2008. The designed pasteurizer maintained water temperature in the range of 60 o C to 70 o C continuously for more than an hour which is enough for deactivation of coliform bacteria. The maximum water temperature on a clear sunny day was found to be 67 o C, corresponding to an ambient temperature of 40 o C. With the pasteurizer facing south, a very little repositioning was required. The low cost and operational simplicity of the pasteurizer make it affordable and usable. It is more useful in rural areas where other sources of energy like electricity and gas are not easily available.

/pdf/use-of-solar-energy-for-disinfection-of-polluted-water-zv20ggain9.pdf

Yasir Jamil

Papers

Effect of ZnO on Photocatalytic Degradation of Rh B and Its Inhibition Activity for C. coli Bacteria

Functionalized cobalt ferrite cubes: toxicity, interactions and mineralization into ferritin proteins

Measurement of ablative laser propulsion parameters for aluminum, Co―Ni ferrite and polyurethane polymer

Elemental Analysis of Kohl Using Laser Ablation and Atomic Absorption Spectroscopy (AAS) techniques

Use of solar energy for disinfection of polluted water