This research aims to study the optical characteristics of semiconductor quantum dots (QDs) composed of CdTe and CdTe/CdSe core-shell structures. It utilizes the refluxed method to synthesize these nanoscale particles and aims to comprehend the growth process by monitoring their optical properties over varied periods of time and pH 12. Specifically, the optical evolution of these QDs is evaluated using photoluminescence (PL) and ultraviolet (UV) spectroscopy. For CdTe QDs, a consistent absorbance and peak intensity increase were observed across the spectrum over time. Conversely, CdTe/CdSe QDs displayed distinctive absorbance and peak intensity variations. These disparities might stem from irregularities in forming selenium (Se) layers around CdTe QDs during growth stages, which could potentially induce quenching in the emission spectrum. The optical examinations unveiled a discernible redshift towards higher wavelength values as the reaction progressed. This spectral shift was coupled with an enlargement in QDs size and a decrease in the energy gap. Using PL and UV analysis techniques enabled a comprehensive study of the optical attributes of the CdTe and CdTe/CdSe QD systems. Our findings underscored the influence of growth conditions and shell materials on the optical properties of QDs. The observed changes in absorbance, peak intensity, wavelength values, QDs size, and energy gap with increasing reaction time provided valuable insights into the growth dynamics of these QD structures.
In this article, a continuous terminal sliding mode control algorithm is proposed for servo motor systems. A novel full-order terminal sliding mode surface is proposed based on the bilimit homogeneous property, such that the sliding motion is finite-time stable independent of the system’s initial condition. A new continuous terminal sliding mode control algorithm is proposed to guarantee that the system states reach the sliding surface in finitetime. Not only the robustness is guaranteed by the proposed controller but also the continuity makes the control algorithm more suitable for the servo mechanical systems. Finally, a numerical example is presented to depict the advantages of the proposed control algorithm. An application in the rota
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The aim of this research is to identify the effectiveness of thinking skills in developing the life skills of the students of the first Academic year, particularly the differences in life skills according to the variable of study specialization (human-scientific). To achieve the research objectives, the life skills scale was constructed on the classification of (WHO). The psychometric properties of the scale were examined. The validity of the scale, which is the final form of (60) items, was valid for measuring the life skills. The scale was then applied to the research sample of (112) students of the first year of the University of Bisha. The SPSS program processed
... Show MoreA program in Visual Basic language was designed to predict the type of radio storm that emitted from Jupiter at specific Local Time (LT) from two different Iraqi locations (Baghdad and Basra), such storms result from the Central Meridian Longitude (CML) of system ??? for Jupiter and phase of Io’s satellite (?Io). Some of these storms are related to position of Io (Io- A,B,C,D) and others are unrelated (non-Io-A,B,C,D) to its position. The input parameters for this program were user specified by determining the observer’s location (longitude), year, month and day. The output program results in form of tables provides the observer with information about the date and the LT of beginning and end of each type of emitted storm. Two Io-storm r
... Show MoreThe study aimed to assess the level of ANG‑2 in MM patients at diagnosis and in remission state and elaborate on its correlation with interleukin‑6 (IL‑6) and beta‑2 microglobulin (B2M) levels. Sixty MM patients; 20 newly diagnosed (ND), and 40 patients in remission were included. Twenty healthy individuals were included as a control group. Plasma levels of ANG‑2, B2M, and IL‑6 were tested by enzyme‑lin ked immunosorbent assay. There are significant statistical differences between ND patients and those in remission in hemoglobin, neutrophil count, blood urea, serum creatinine, glomerular filtration rate, B2M, IL6, and ANG‑2 (P = 0.001, 0.033, 0.005, 0.001, 0.001, 0.001, 0.004, and 0.001, respectively). ANG‑2 showed signifi
... Show MoreThis study was conducted to evaluate the efficacy of different techniques for extraction and purification of Tomato yellow leaf curl virus (TYLCV). An isolate of the virus free of possible contamination with other viruses infecting the same host and transmitted by the same vector Bemisia tabaci Genn. was obtained. This was realized by indicator plants and incubation period in the vector. Results obtained revealed that the virus infect Nicotiana glutinosa without visible symptoms, while Nicotiana tabaccum var. White Burley was not susceptible to the virus. The incubation period of the virus in the vector was found to be 21 hrs. These results indicate that the virus is TYLCV. Results showed that Butanol was more effective in clarification the
... Show MoreBackground: Limited data are available on the dimensional stability and surface roughness of ThermoSens, which is a material used in denture processing. This study aimed to measure the vertical teeth changes and surface roughness of ThermoSens dentures prepared using three different investment materials. Materials and methods: For the dimensional changes test, 30 complete maxillary dentures were prepared using different investment methods: group I, dental stone; group II, silicone putty; and group III, a mixture of dental stone and plaster (ratio, 1:1; n = 10 for each group). Four screws were attached to the dentures: two were attached to the buccal surface of the canine and first molar, and the other two were attached in the flange areas o
... Show MoreHypertension is one of the main causes of heart disease; beta- blockers play a crucial role in the management of patients with essential hypertension. Bisoprolol is one of the widely used drugs for the treatment of hypertension. Bisoprolol tablets were prepared by two methods (direct and wet) using different proportion and types of diluents, different binder types and forms, then evaluated for, weight variation, hardness, friability, disintegration time and dissolution rate. The results were compared with a reference Bisoprolol tablet.
Both methods of preparation wet and direct compression method gave good results, which are consistent with the requirements of British Pharmacopeia and United States Pharmacopeia. It was found that
... Show MoreInternet of Things (IoT) technology could be an effective solution to accomplish real-time retrieval of historical electronic health records (EHRs) to present better service of healthcare. In a pilgrimage environment such as the Hajj, IoT can be applied by identifying the non-local patients as electronic tags, and the tag data can be read by wireless sensors. The data that is collected using Radio-Frequency Identification (RFID) can be acquired from a Wireless Sensor Network (WSN) in order to accomplish many decisions, such as sending an ambulance to a patient’s location, sending an emergency alert to his immediate family circle, and retrieving his EHR from a database. The main contribution of this research is to propose a conceptual IoT
... Show MoreAlloys of InxSe1-x were prepared by quenching technique with
different In content (x=10, 20, 30, and 40). Thin films of these alloys
were prepared using thermal evaporation technique under vacuum of
10-5 mbar on glass, at room temperature R.T with different
thicknesses (t=300, 500 and 700 nm). The X–ray diffraction
measurement for bulk InxSe1-x showed that all alloys have
polycrystalline structures and the peaks for x=10 identical with Se,
while for x=20, 30 and 40 were identical with the Se and InSe
standard peaks. The diffraction patterns of InxSe1-x thin film show
that with low In content (x=10, and 20) samples have semi
crystalline structure, The increase of indium content to x=30
decreases degree o