Detection of Pb in Whitening Creams via Laser Induced Breakdown Spectroscopy

Recently whitening creams have been widely used to protect UV light exposure due to the depletion of ozone layer. The demand attracts the rapid growth of various whitening creams in the market. The detection is required in order to determine the constituent of the whitening cream, whether it contains dangerous element like heavy metal (Pb, Hg or Cr). In this attempt, laser induced breakdown spectroscopy (LIBS) technique was deployed to analyse the existence of heavy metal. Several whitening creams available in retail shop and open market were investigated. Cryogenically frozen technique was utilized to convert the emulsion into solid form. Lead Pb was detected in all the tested samples in the range of 2 - 5 ppm.  The LIBS results were validated by Inductive Couple Plasma Mass Spectroscopy (ICP-MS) technique.  The high sensitivity, portable and in-situ LIBS system allow simple, faster and easy heavy metal detection.  This enhances the procedure of inspection in cosmetic industrie

Weighing the galactic disc using the Jeans equation: lessons from simulations

Using three-dimensional stellar kinematic data from simulated galaxies, we examine the efficacy of a Jeans equation analysis in reconstructing the total disk surface density, including the dark matter, at the ‘Solar’ radius. Our simulation data set includes galaxies formed in a cosmological context using state-of-the-art high-resolution cosmological zoom simulations, and other idealized models. The cosmologically formed galaxies have been demonstrated to lie on many of the observed scaling relations for late-type spirals, and thus offer an interesting surrogate for real galaxies with the obvious advantage that all the kinematical data are known perfectly. We show that the vertical velocity dispersion is typically the dominant kinematic quantity in the analysis, and that the traditional method of using only the vertical force is reasonably effective at low heights above the disk plane. At higher heights the inclusion of the radial force becomes increasingly important. We also show that the method is sensitive to uncertainties in the measured disk parameters, particularly the scalelengths of the assumed double exponential density distribution, and the scalelength of the radial velocity dispersion. In addition, we show that disk structure and low number statistics can lead to significant errors in the calculated surface densities. Finally, we examine the implications of our results for previous studies of this sort, suggesting that more accurate measurements of the scalelengths may help reconcile conflicting estimates of the local dark matter density in the literature

Simulation Of Sinusoidal Commutation Of Brushless Motor For Starting Of Linear Engine - Generator

To start a free-piston linear engine-generator (LG), it requires favorable amplitude and speed for combustion to occur. The LG is able to do reciprocating motion for starting. Indeed, to do the reciprocating motion, there are some mechanical factors to be taken into consideration such as compression pressure of the engine cylinders and their air spring character. For this project, it only focuses on the electrical subsystem required to provide for the motoring force for starting

Chemical analysis of NGC 6528: one of the most metal-rich bulge globular cluster

The Bulge Globular Clusters (GCs) are key tracers of this central ancient component of our Galaxy. It is essential to understand their formation and evolution to study that of the bulge, as well as their relationship with the other Galactic GC systems (halo and disk GCs). Our main goals are to obtain detailed abundances for a sample of seven red giant members of NGC 6528 in order to characterize its chemical composition and study the relationship of this GC with the bulge, and with other bulge, halo and disk GCs. Moreover, we analyze this cluster$'$s behavior associated with the Multiple Populations (MPs) phenomenon. We obtained the stellar parameters and chemical abundances of light elements (Na, Al), iron-peak elements (V, Cr, Mn, Fe, Co, Ni, Cu), {\alpha}-elements (O, Mg, Si, Ca, Ti) and heavy elements (Zr, Ba, Eu) in seven red giant members of NGC 6528 using high resolution spectroscopy from FLAMES-UVES. We obtained in six stars of our sample a mean iron content of [Fe/H]=-0.14+/-0.03 dex, in good agreement with other studies. We found no significant internal iron spread. We detected one candidate variable star, which was excluded from the mean in iron content, we derived a metallicity in this star of [Fe/H]=-0.55+/-0.04 dex. Moreover, we found no extended O-Na anticorrelation but instead only an intrinsic Na spread. In addition, NGC 6528 does not exhibit a Mg-Al anticorrelation, and no significant spread in either Mg or Al. The {\alpha} and iron-peak elements show good agreement with the bulge field star trend. The heavy elements are slightly dominated by the r-process. The chemical analysis suggests an origin and evolution similar to that of typical old Bulge field stars. Finally, we find remarkable agreement in the chemical patterns of NGC 6528 and another bulge GC, NGC 6553, suggesting a similar origin and evolution.Comment: Accepted for publication in A&A. 12 pages, 13 figures, 4 table

Corporate Identity Management (CIM) Model in Malaysian Higher Education Sector: Literature Review and Hypothesis Development

Corporate Identity Management (CIM) in universities has been acknowledged in marketing literature as an important area of research. Research within the current spectrum of CIM indicates some ambiguities surrounding corporate identity in higher education. However, very few studies are available in the field of corporate identity within universities. Accordingly, the objective of this study is to examine the relationships between university’s CIM and organizational performance, and also identify the relevant underlying mechanisms in Malaysian higher-education sector. Based on a review of the existing literature in a range of areas, this study proposes a conceptual model of the positive relationships between CIM activities in universities with internal brand, transformational leadership and organisational culture. The proposed conceptual model is developed based on three main theories--social identification theory, transformational leadership theory and social learning theory

Development on collation of tuna fishery statistics for the Southeast Asian region

SEAFDEC has been responsible since June 1996 for the collation of tuna fishery statistics in the Southeast Asian region. The Marine Fishery Resource Development and Management Department (MFRDMD) of SEAFDEC has requested countries fishing for tuna in the region to provide statistical data for collation. MFRMDM will maintain appropriate databases and publish the data or disseminate it upon request. It has also developed a computer programme known as the Fishery Resources Information and Management System to facilitate information transfer to and from Member Countries. A list is given of species covered, which include 3 major groups of tunas and tuna-like species (tunas and bonitos, seerfish and billfish). A brief account is given of development and progress made in this sector, outlining also the various problems encountered in the collation of tuna fishery statistics provided by Member Countries

Ultra-deep GEMINI near-infrared observations of the bulge globular cluster NGC 6624

We used ultra-deep $J$ and $K_s$ images secured with the near-infrared GSAOI camera assisted by the multi-conjugate adaptive optics system GeMS at the GEMINI South Telescope in Chile, to obtain a ($K_s$, $J-K_s$) color-magnitude diagram (CMD) for the bulge globular cluster NGC 6624. We obtained the deepest and most accurate near-infrared CMD from the ground for this cluster, by reaching $K_s$ $\sim$ 21.5, approximately 8 magnitudes below the horizontal branch level. The entire extension of the Main Sequence (MS) is nicely sampled and at $K_s$ $\sim$ 20 we detected the so-called MS "knee" in a purely near-infrared CMD. By taking advantage of the exquisite quality of the data, we estimated the absolute age of NGC 6624 ($t_{age}$ = 12.0 $\pm$ 0.5 Gyr), which turns out to be in good agreement with previous studies in the literature. We also analyzed the luminosity and mass functions of MS stars down to M $\sim$ 0.45 M$_{\odot}$ finding evidence of a significant increase of low-mass stars at increasing distances from the cluster center. This is a clear signature of mass segregation, confirming that NGC 6624 is in an advanced stage of dynamical evolution.Comment: Accepted for publication by ApJ. 39 pages, 19 figures, 1 tabl

A panchromatic view of the bulge globular cluster NGC 6569

We used high-resolution optical HST/WFC3 and multi-conjugate adaptive optics assisted GEMINI GeMS/GSAOI observations in the near-infrared to investigate the physical properties of the globular cluster NGC 6569 in the Galactic bulge. We have obtained the deepest purely NIR color-magnitude diagram published so far for this cluster using ground-based observations, reaching $K_{s}$ $\approx$ 21.0 mag (two magnitudes below the main-sequence turn-off point). By combining the two datasets secured at two different epochs, we determined relative proper motions for a large sample of individual stars in the center of NGC 6569, allowing a robust selection of cluster member stars. Our proper motion analysis solidly demonstrates that, despite its relatively high metal content, NGC 6569 hosts some blue horizontal branch stars. A differential reddening map has been derived in the direction of the system, revealing a maximum color excess variation of about $\delta E(B-V)$ $\sim$ 0.12 mag in the available field of view. The absolute age of NGC 6569 has been determined for the first time. In agreement with the other few bulge globular clusters with available age estimates, NGC 6569 turns out to be old, with an age of about 12.8 Gyr, and a typical uncertainty of 0.8-1.0 Gyr.Comment: 25 pages, 16 Figures, 1 Table. Accepted for publication in Ap