3,926 research outputs found
Spectral studies of some hydroxy-derivatives of anthraquinones
The u.v., visible, and i.r. spectra of several hydroxy-anthraquinones are discussed and the bands are assigned. These bands are compared with those of anthracene and anthraquinone. The band at 207 nm. is assigned to a n-sigma* transition; the bands at 252, 272, and 326 nm. are assigned by measuring spectra in solvents of various polarities. The stability constant for the 12-dihydroxyanthraquinone-ethanol complex is obtained
Ultraviolet and Infrared Spectra of Some p-Nitrobenzyl Phenyl Ethers
The UV-spectra of substituted p-nitrobenzyl phenyl ethers in
ethanol and carbon tetrachloride were recorded. The effect of
substitution on band position and intensity is correlated with the
electronic nature of the group. The IR-spectra are analysed and the
position of certain bands ii;; dis.cussed in terms of molecular structure
Criminal Protection from Misleading Advertisements on Social Media Under the Bahraini Consumer Protection Law
Providing effective criminal protection for the consumer from the danger of misleading advertisements spread through social media has become an imperative necessity. It contains many legal problems, especially in light of the increasing spread of such advertisements simultaneously with the significant increase of e-commerce. In this paper, we demonstrate the adequacy of criminal protection for the consumer provided by the Bahraini Consumer Protection Law in the face of misleading and deceptive acts through commercial advertisements using social media, and the extent of consumer awareness of it
Use of Infrared Light to Improve Breast Sonographic images
It is well known that sonography is not the first choice in detecting early breast tumors. Improving the resolution of breast sonographic image is the goal of many workers to make sonography a first choice examination as it is safe and easy procedure as well as cost effective. In this study, infrared light exposure of breast prior to ultrasound examination was implemented to see its effect on resolution of sonographic image. Results showed that significant improvement was obtained in 60% of cases
Impedance interaction between islanded parallel voltage source inverters and the distribution network
In an islanded microgrid consisting of parallel-connected inverters, the interaction between an inverter’s output impedance (dominated by the inverter’s filter and voltage controller) and the impedance of the distribution network (dominated by the other paralleled inverters’ output
impedances and the interconnecting power cables) might lead to instability. This paper studies this phenomenon using root locus analysis. A controller based on the second derivative of the output capacitor voltage is proposed to enhance the stability of the system. Matlab simulation results are presented to confirm the validity of the theoretical analysis and the robustness of the proposed controlle
The effect of N-acetylcysteine on the sensory retina of male albino rats exposed prenatally to cypermethrin
Background: Cypermethrin (CYP), a pyrethroid that is globally used in the field and house to fight the pests. CYP can induce cellular toxicity and cross the placental barrier. N-acetylcysteine (NAC) can fight the prenatal exposure to the inflammation. This work aimed to study, for the first time, the effects of NAC on the sensory retina of male albino rats exposed prenatally to cypermethrin.
Materials and methods: Twenty-four sexually mature female albino rats and 12 male albino rats were allowed for mating and divided equally into the following groups: group I (control group): kept without treatment; group II (NAC group): received 1 g/kg/day NAC diluted in distilled water orally by gastric tube from the 7th day of gestation till delivery; group III (CYP group): received 12 mg/kg/day of cypermethrin orally by gastric tube from the 7th day of gestation till delivery; group IV (CYP and NAC group): received 12 mg/kg/day of cypermethrin and 1 g/kg/day of NAC. The ten male offspring of each group were divided into subgroups a and b that were sacrificed at the age of 7th and 14th days postnatal, respectively. At the end of the experiment, the eye samples were subjected to histological, immunohistochemical and morphometric studies.
Results: Concerning the different previous studies, the sensory retina of CYP subgroups showed vacuolation of the inner and outer plexiform layers, dilated congested blood vessels, hyalinisation and disorganisation of the photoreceptor layer. Also, the expression of collagen IV and caspase 3 (a marker of apoptosis) was up-regulated in the CYP subgroups.
Conclusions: N-acetylcysteine significantly protected the sensory retina from the damaging effects of CYP. NAC could be considered as a good protective agent against the damaging effect of CYP on the sensory retina
Metallicities of 0.3<z<1.0 Galaxies in the GOODS-North Field
We measure nebular oxygen abundances for 204 emission-line galaxies with
redshifts 0.3<z<1.0 in the Great Observatories Origins Deep Survey North
(GOODS-N) field using spectra from the Team Keck Redshift Survey (TKRS). We
also provide an updated analytic prescription for estimating oxygen abundances
using the traditional strong emission line ratio, R_{23}, based on the
photoionization models of Kewley & Dopita (2003). We include an analytic
formula for very crude metallicity estimates using the [NII]6584/Halpha ratio.
Oxygen abundances for GOODS-N galaxies range from 8.2< 12+log(O/H)< 9.1
corresponding to metallicities between 0.3 and 2.5 times the solar value. This
sample of galaxies exhibits a correlation between rest-frame blue luminosity
and gas-phase metallicity (i.e., an L-Z relation), consistent with L-Z
correlations of previously-studied intermediate-redshift samples. The zero
point of the L-Z relation evolves with redshift in the sense that galaxies of a
given luminosity become more metal poor at higher redshift. Galaxies in
luminosity bins -18.5<M_B<-21.5 exhibit a decrease in average oxygen abundance
by 0.14\pm0.05 dex from z=0 to z=1. This rate of metal enrichment means that
28\pm0.07% of metals in local galaxies have been synthesized since z=1, in
reasonable agreement with the predictions based on published star formation
rate densities which show that ~38% of stars in the universe have formed during
the same interval. (Abridged)Comment: AASTeX, 49 pages, 16 figures, accepted for publication in The
Astrophysical Journa
- …