A theoretical quantum study of the electronic properties of mentoxy dichloro phosphorous (C10H19OPCl2)

Indexación: Scopus.A theoretical quantum study of the organophosphorus compound with formula C10H19OPCl2 (MEPCL2) was carried out. The results of the calculations show excellent agreement between experimental and computed frequencies evaluated at the B3LYP/6-311++G(d,p) level of theory. A study of the electronic properties, such as excitation energies and wavelengths were performed employing the time-dependent DFT (TD-DFT) method. Global a chemical reactivity of MEPCL2 was analyzed through global reactivity descriptors, while its local reactivity was analyzed by mean maps of the electrostatic potential. Also, the orbital energies values suggest that a charge transfer is occurring within the molecule. © 2018 American Physical Society.https://scielo.conicyt.cl/scielo.php?script=sci_arttext&pid=S0717-97072018000103887&lng=en&nrm=iso&tlng=e

Preparation and Characterization of Cerium (III) Doped Captopril Nanoparticles and Study of their Photoluminescence Properties

Indexación: Web of Science. DOAJ.In this research Ce3+ doped Captopril nanoparticles (Ce3+ doped CAP-NP) were prepared by a cold welding process and have been studied. Captopril may be applied in the treatment of hypertension and some types of congestive heart failure and for preventing kidney failure due to high blood pressure and diabetes. CAP-NP was synthesized by a cold welding process. The cerium nitrate was added at a ratio of 10% and the optical properties have been studied by photoluminescence (PL). The synthesized compounds were characterized by Fourier transform infrared spectroscopy. The size of CAP-NP was calculated by X-ray diffraction (XRD). The size of CAP-NP was in the range of 50 nm. Morphology of surface of synthesized nanoparticles was studied by scanning electron microscopy (SEM). Finally the luminescence properties of undoped and doped CAP-NP were compared. PL spectra from undoped CAP-NP show a strong pack in the range of 546 nm after doped cerium ion into the captopril appeared two bands at 680 and 357 nm, which is ascribed to the well-known 5d–4f emission band of the cerium.http://www.degruyter.com/view/j/chem.2016.14.issue-1/chem-2016-0008/chem-2016-0008.xm

PREPARATION, IDENTIFICATION AND BIOLOGICAL PROPERTIES OF NEW FLUORIDE NANOCOMPOUNDS

Indexación: Web of Science; Scopus.Nanoparticles (NPs) of new fluoride (SrF2 and MgF2) nanocompounds were synthesized by the simple chemical method of precipitation in ethanol. Synthesis of the strontium fluoride (SrF2)-magnesium oxide (MgO) nanocomposite was achieved through the ultrasonic method. These prepared nanopowders were characterized through Fourier transform infrared (FT-IR) spectroscopy, ultraviolet-visible (UV-Vis) spectroscopy, Powder X-ray Diffraction (PXRD) and Scanning Electron Microscopy (SEM). FT-IR confirmed the purity of the synthesized fluoride NPs by evaluation of the vibrations, and UV-Visible showed the intense absorption peaks of NPs. PXRD analysis indicated the average of particle size, and SEM demonstrated a nearly spherical morphology of the NPs. The antibacterical properties of the nanopowders on Staphylococcus Aureus, Bacillus Subtilis and E. Aklay bacteria were studied, with the strongest effect by the magnesium fluoride (MgF2) NPs and the SrF2-MgO nanocomposite.http://ref.scielo.org/yfr3f

Study of genetic diversity of wild Caspian trout Salmo trutta caspius in the Sardabrud and Astara Rivers, using D-Loop region sequencing

In this study the genetic diversity of wild Caspian trout (Salmo trutta caspius) in the Sardabroud and Astara Rivers was evaluated using D-Loop region sequencing. For this purpose, 35 specimens of adult Caspian brown trout were collected from these rivers in the Mazandarn and Gilan Provinces in fall and winter 2011. Approximately 3-5 g of soft and fresh fin tissue was isolated and fixed in ethanol 96% and then transferred to the Caspian Sea Ecology Research Center Genetics Laboratory in Sari, Iran. Genomic DNA from the samples was extracted using Ammonium Acetate Method. The quality and quantity of the extracted DNA were assessed by spectrophotometer and agarose gel (1%) electrophoresis. Polymerase Chain Reaction (PCR) was performed on the target DNA using a primers sequence D-Loop region of mtDNA molecule. Then the product was purified and DNA sequencing was carried out using chain termination method. The D-Loop region of Caspian trout contained 654 bp. Data were analyzed using Bio-Edit, DnaSP, Arlequin and Mega software. 20 and 15 haplotypes was observed in Sardabrud and Astara River. The DNA sequence of one of them was recorded in Gene Bank with numbers KC991027 and KF015727. 223 and 240 polymorphic loci were detected in Sardabrud and Astara River that all of them were out of Hardy-Weinberg equilibrium (p<0.05). Average nucleotide and haplotype diversity were 0.127±0.067, 1.000±0.005 in Sardabrud River and 0.118±0.063 and 1.000±0.005 in Astara River

Shape memory nanocomposite of poly(L-lactic acid)/graphene nanoplatelets triggered by infrared light and thermal heating

In this study, the effect of graphene nanoplatelets (GNPs) on the shape memory properties of poly(L-lactic acid) (PLLA) was studied. In addition to thermal activation, the possibility of infrared actuating of thermo-responsive shape memory PLLA/GNPs nanocomposite was investigated. The incorporated GNPs were expected to absorb infrared wave’s energy and activate shape memory PLLA/GNPs. Different techniques such as differential scanning calorimetry (DSC), wide-angle X-ray diffraction (WAXD), field emission gun scanning electron microscope (FEG-SEM) and dynamic mechanical thermal analysis (DMTA) were used to characterize samples. DSC and WAXD results indicated that GNPs augmented crystallinity due to nucleating effect of graphene particles. GNPs improved both thermal and infrared activating shape memory properties along with faster response. Pure shape memory PLLA was slightly responsive to infrared light and its infrared actuated shape recovery ratio was 86% which increased to more than 95% with loading of GNPs. Drastic improvement in the crystallinity was obtained in nanocomposites with lower GNPs contents (0.5 and 1 wt%) due to finer dispersion of graphene which resulted in more prominent mechanical and shape memory properties enhancement. Infrared activated shape memory PLLA/GNPs nanocomposites can be developed for wireless remote shape control of smart medical and bio-systems

The impact of the COVID-19 pandemic on retail in city centres

Over the past few decades, city centres and their retail spaces have undergone significant changes and have struggled to remain economically viable. The COVID-19 pandemic and the public health response to the crisis have exacerbated this situation and posed a serious challenge to the already economically struggling city centres. Recommendations for how city centres should respond to the current crisis are urgently needed, but despite this, few studies have focused on the impact of COVID-19 on retailing in city centres. This paper conducts a systematic review to provide a better understanding of how retail in city centres has been affected by the pandemic. It also offers insights to support better decision making about the future of retailing in city centres and provides recommendations for ensuring a sustainable future for city centres. The review, conducted between the 20th of November 2021 and the 20th of January 2022, shows that the COVID-19 pandemic and subsequent public health response have intensified some considerable changes in customer preferences and the role of city centres. As a result of these changes, more retailers have adopted multichannel retailing and repositioning strategies. This paper concludes that in order to create vibrant and sustainable city centres post-pandemic, decision makers should support the repurposing of vacant and underperforming retail spaces, promote an experience economy, and create episodic retail spaces

Pre-stimulus alpha activity modulates face and object processing in the intra-parietal sulcus, a MEG study

Face perception is crucial in all social animals. Recent studies have shown that pre-stimulus oscillations of brain activity modulate the perceptual performance of face vs. non-face stimuli, specifically under challenging conditions. However, it is unclear if this effect also occurs during simple tasks, and if so in which brain regions. Here we used magnetoencephalography (MEG) and a 1-back task in which participants decided if the two sequentially presented stimuli were the same or not in each trial. The aim of the study was to explore the effect of pre-stimulus alpha oscillation on the perception of face (human and monkey) and non-face stimuli. Our results showed that pre-stimulus activity in the left occipital face area (OFA) modulated responses in the intra-parietal sulcus (IPS) at around 170 ms after the presentation of human face stimuli. This effect was also found after participants were shown images of motorcycles. In this case, the IPS was modulated by pre-stimulus activity in the right OFA and the right fusiform face area (FFA). We conclude that pre-stimulus modulation of post-stimulus response also occurs during simple tasks and is therefore independent of behavioral responses