In this paper, we investigate prime near – rings with two sided α-n-derivations
satisfying certain differential identities. Consequently, some well-known results
have been generalized. Moreover, an example proving the necessity of the primness
hypothesis is given.
Background: This in vitro study evaluated the effect of canal dryness and flaring on the accuracy of two electronic apex locators for working length (WL) determination. Materials and methods: Sixty extracted teeth were used, after access opening was done, the occlusal surface was flattened to create stable reference point. The teeth were randomly divided into two equal main groups of flared and unflared group each one of 30 teeth. The flaring was done with Gates Glidden drills. The two main groups were further subdivided into two subgroups: dry canal and wet canal using 5.25% sodium hypochlorite groups, Electronic WL of each sample was determined using both Root ZX and i-Root apex locator. Consequently, histologic WL was determined by shav
... Show MoreWheat (Triticum aestivum L.) is one of the Poaceae family (Gramineae). Is momentous for human nutrition, and the stresses can affect strongly on the phenotype characteristics of the plant. The aim of this study was to determine how electric shock on germinated grain (for 2.5, 5, and 7.5 mins.) and heat shock at ( 35 oC, 40 oC and 45 oC) applied after phase out the radical length of 2-5 mm, from the grain of two wheat Varieties: “Baghdad 1” and “Babylon 113”. The electric shock for 2.5 mins., lead to delay of flowering, from day to 50 % flowering was 93 day, as well as, gave lowest value of plant height 64.5cm and lowest spike length was 10.7 cm. While The highest flag leaf area was obtained by electric shock for 5 mins. was 56.6
... Show MoreThis study was aimed to reduce the amount of the sprayed solution lost during trees spraying. At the same time, the concentration of the sprayed solution on the target (tree or bush) must be ensured and to find the best combination of treatments. Two factors controls the spraying process: (i) spraying speed (1.2 km/h, 2.4 km/h, 3.6 km/h), and (ii) the type of sensor. The test results showed a significant loss reduction percentage. It reached (6.05%, 5.39% and 2.05%) at the speed (1.2 km/h, 2.4 km/h, 3.6 km/h), respectively. It was noticed that when the speed becomes higher the loss becomes less accordingly. The interaction between the 3.6 km/h speed and the type of Ultrasonic sensor led to a decrease in the percentage of the spray
... Show MoreObjective: To evaluate the effect of mouth rinses (Biofresh and ZAK) on the surface micro hardness
of two light cure restorative material (Tetric ceram ivoclar-vivadent) and (3M Z 250) dental
composite.
Methodology: The microhardness values of (sixty) composite specimens were measured at the top
surfaces after 24 hours of immersion in different solutions (Biofresh, Zak mouth wash and distilled
water as control). Comparison done using descriptive statistics (mean, SD, SEM, minimum and
maximum values) and inferential statistics (ANOVA and LSD) test.
Results: The biofresh mouth rinse which has high alcohol containing has less effect on
microhardness of tetric ceram than the zak &distiled water , while the effect
Finding a path solution in a dynamic environment represents a challenge for the robotics researchers, furthermore, it is the main issue for autonomous robots and manipulators since nowadays the world is looking forward to this challenge. The collision free path for robot in an environment with moving obstacles such as different objects, humans, animals or other robots is considered as an actual problem that needs to be solved. In addition, the local minima and sharp edges are the most common problems in all path planning algorithms. The main objective of this work is to overcome these problems by demonstrating the robot path planning and obstacle avoidance using D star (D*) algorithm based on Particle Swarm Optimization (PSO)
... Show MoreThis study was carried out on two species of the Hygromiidae family Monacha
cantiana and Candidula gigaxii collected from six sites in three central Iraq
provinces (Baghdad , Babylon and Karbala) . A total of 1318 individuals of Monacha
cantiana and 173 of Candidula gigaxii have been examined during the study period
from October 2013 to July 2014.The study included estimation of species relative
abundance, population density and relationship with some physico- chemical
properties of the soil; temperature, moisture and pH.
The Monacha cantiana was present at all sites but with varying numbers, while
Candidula gigaxii was confined to only three sites: Aljadiriyah and Zafaraniya at
Baghdad, and Hindiya dam at Baby
Five N-substituted acrylamides were prepared by reaction of substituted aromatic primary amines with acryloyl chloride in the presence of triethyl amine. The synthesized acrylamides were allowed to introduce copolymerization reaction with three vinylic monomers including acrylonitrile, methyl acrylate and methyl methacrylate respectively to obtain eleven new copolymers having different physical properties which may used in different applications.
In this work, porous Silicon structures are formed with photochemical etching process of n-type Silicon(111) wafers of resistivity (0.02.cm) in hydrofluoric acid (HF) of concentration (39%wt) under light source of tungeston halogen lamp of (100 Watt) power. Samples were anodized in a solution of 39%HF and ethanol at 1:1 for 15 minutes. The samples were realized on n-type Si substrates Porous Silicon layers of 100m thickness and 30% of porousity. Frequency dependence of conductivity for Al/PSi/Si/Al sandwich form was studied. A frequency range of 102-106Hz was used allowing an accurate determination of the impedance components. Their electronic transport parameters were determined using complex impedance measurements. These measu
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