Investigation of mesomorphic properties of new 1,3,4-thiadiazolines (which are synthesised via many steps in Scheme 1) was carried out in this study. These compounds are designed to have a heterocyclic unit, a carboxylate linkage group and a polar ether chain at the end of the molecule adjacent to the benzene ring, which enhance the dipolar interactions forces (varied from one to eight carbons) to investigate the association properties of their phases. The structure of the target compounds and the intermediates were confirmed by 1H NMR, 13C NMR, mass and FTIR spectral techniques. Polarised microscopic studies revealed that all the compounds in the series exhibited enantiotropic liquid crystalline properties. This was further confirmed using differential scanning calorimetric experiments. The synthesised compounds type [V]n in this study displayed different liquid crystalline mesophases and the homologous [V] having an alkoxy terminal group (n = 1–3) exhibited nematic phase, whilst the last derivatives of the series (4–8), displayed smectic A phase.
Background: White spot lesions (WSLs) are subsurface enamel demineralization manifested as white opacities which had an esthetic problem. The purpose of this in-vitro study was to evaluate the lesion depth improvement of WSLs following application of fluoride varnish, tooth mousse and resin infiltration (ICON). Materials and methods: Artificial WSLs were created on 120 premolar teeth using demineralization solution with pH (4-4.5). Samples randomly allocated into four groups; fluoride varnish, tooth mousse, ICON and untreated group. Groups were discolored in Cola and orange juice for 24 hours. Teeth were ground sectioned by longitudinal cutting then these sections examined and photographed under stereomicroscope at 12X magnification then an
... Show MoreThe topic of urban transformations has attracted the attention of researchers as it is one of the basic issues through which cities can be transformed towards sustainability. A specific level of transformation levels according to a philosophical concept known as a crossing. This article has relied on a specific methodology that aims to find a new approach for urban transformation based on the crossing concept. This concept derives from philosophical entrances based on the concepts of (being, process, becoming, and integration). Four levels have been for the crossing are (normal, ascending, leap, and descending). Each of these levels includes specific characteristics that distinguish it. The results showed that there is no descending
... Show MoreNano gamma alumina was prepared by double hydrolysis process using aluminum nitrate nano hydrate and sodium aluminate as an aluminum source, hydroxyle poly acid and CTAB (cetyltrimethylammonium bromide) as templates. Different crystallization temperatures (120, 140, 160, and 180) 0C and calcinations temperatures (500, 550, 600, and 650) 0C were applied. All the batches were prepared at PH equals to 9. XRD diffraction technique and infrared Fourier transform spectroscopy were used to investigate the phase formation and the optical properties of the nano gamma alumina. N2 adsorption-desorption (BET) was used to measure the surface area and pore volume of the prepared nano alumina, the particle size and the
... Show MoreГоды, принадлежащие концу XIX – началу XX столетия, вошли в русскую литературу под красивым названием Серебряный век. В это время в стране появился целый ряд выдающихся поэтов, имена которых навсегда останутся в русской и мировой литературе. Это Ахматова, Гумилев, Блок, Маяковский и многие другие. Все эти люди творили в нелегкое для России время. Началом Серебряного века условно считают 189
... Show MoreThe internet, unlike other traditional means of communication, has a flexibility to stimulate the user and allows him to develop it. Perhaps, the reason for the superiority of the internet over other traditional means of communication is the possibility of change and transmission from one stage to another in a short period. This means that the internet is able to move from the use to the development of the use and then the development of means and innovation as the innovation of the internet is a logical product of the interaction of the user with the network. The internet invests all the proposals and ideas and does not ignore any even if it is simple. This is represented in social networking sites which in fact reflects personal emotio
... Show Morefashion designers who have benefited greatly from the mobilization of ancient aesthetic ideas in the heritage of the people and guaranteed in their productions so that there is no change In the aesthetic value created by the designers of the research in the ancient heritage to find new signs that reflect the connection of man to the present as the aesthetic value of all the man created by the designs of fabrics and fashion through the ages The problem of research was determined in the absence of a precise understanding of the nature of classical thought in fashion and the absence of a clear perception of the sustainability of this thought in contemporary fashion. He
... Show MoreThis research focuses on the synthesis of carbon nanotube (CNT) and Poly(3-hexylthiophene) (P3HT) (pristine polymer) with Ag doped (CNT/ P3HT@Ag) nanocomposite thin films to be utilised in various practical applications. First, four samples of CNT solution and different ratios of the polymer (P3HT) [0.1, 0.3, 0.5, and 0.7 wt.%] are prepared to form thin layer of P3HT@CNT nanocomposites by dip-coating method of Ag. To investigate the absorption and conductivity properties for use in various practical applications, structure, morphology, optical, and photoluminescence properties of CNT/P3HT @Ag nanocomposite are systematically evaluated in this study. In this regard, the UV/Vis/NIR spectrophotometer in the wavelength range of 350 to 7
... Show MoreIn this work, Kinetic Phosphorescence Analyzer (KPA) has been used to measure the concentrations of uranium (UC) and Amorphous crystals (AMO) in urine samples of breast cancer patients in Baghdad. Additionally, a relation between UC and AMO with respect to patient's age has been deduced and studied.
Forty one urine samples of patients and five for healthy were taken from females lived in different residential area of Baghdad. The measured maximum UC value for urine samples of patients was 2.35 ± 0.053, the minimum value was 0.86 ± 0.034 μg/L, and an overall average was 1.6 ± 0.027 μg/L while the average UC for healthy females was 1.03 ± 0.020 μg/L.
From these results, AMO concentrations were found for all breast cancer patie
Simplification of new fashion design methods