The pure ZnS and ZnS-Gr nanocomposite have been prepared
successfully by a novel method using chemical co-precipitation. Also
conductive polymer PPy nanotubes and ZnS-PPy nanocomposite
have been synthesized successfully by chemical route. The effect of
graphene on the characterization of ZnS has been investigated. X-ray
diffraction (XRD) study confirmed the formation of cubic and
hexagonal structure of ZnS-Gr. Dc-conductivity proves that ZnS and
ZnS-Gr have semiconductor behavior. The SEM proved that
formation of PPy nanotubes and the Gr nanosheet. The sensing
properties of ZnS-PPy/ZnS-Gr for NO2 gas was investigated as a
function of operating temperature and time under optimal condition.
The sensitivity, response time and recovery time were calculated
with different operating temperatures.
The encoding of long low density parity check (LDPC) codes presents a challenge compared to its decoding. The Quasi Cyclic (QC) LDPC codes offer the advantage for reducing the complexity for both encoding and decoding due to its QC structure. Most QC-LDPC codes have rank deficient parity matrix and this introduces extra complexity over the codes with full rank parity matrix. In this paper an encoding scheme of QC-LDPC codes is presented that is suitable for codes with full rank parity matrix and rank deficient parity matrx. The extra effort required by the codes with rank deficient parity matrix over the codes of full rank parity matrix is investigated.
الحمدُ للهِ رب العالمين ، والصلاة والسلام على نبيه الأمين محمد r وعلى آله الطيبين الطاهرين ، وأصحابه الغر الميامين:
تعد الصورة السمعية مفهوما بيانيا نجده في البلاغة العربية واضحاً مؤثرا، مؤديا دورا جوهريا في إيصال الفكرة التي يروم الأديب إيصالها إلى المتلقي ولا تبدو السمعية واضحة إلاّ إذا نظر إليها في حالة أدبيه تهز كيان الشاعر  
... Show MoreThe petroleum system of Halfaya oil field shows that the hydrocarbon generation of these Formations such as Sha′uiba and Nahr Umr are immature and have generated few oil TR ≤ 50% which are neglected as compared to Formations below them which are very rich source rock. The Formations of Yamama, Ratawi and Sulaiy are mature with TR ≤ 100%. Other Formations such as Sargelu ,Najma,Zubair and Gotnia are with very high maturity with TR ≥ 100% and completely generated hydrocarbon and depleted after hydrocarbon are expelled and migrate to reservoir rock of structure traps and this study indicates that the major seals of Upper Jurassic are Gotnia and Allan Formations and of Middle Miocene is LowerFars fatha Formation.
The present study evaluates the insecticidal activity of (Acetone, 80% Methanol and water) crude leaf extract of AdhatodavasicaagainstBemisiatabaci. The extracts of (Acetone, Methanol 80%) showed 100, 86.6% mortality of nymphsBemisiatabaci at 5% concentration. Then the extracts of (Acetone, Methanol 80%) showed 100, 90% mortality of pupaBemisiatabaci at 5% concentration. Phytochemical screening revealed the presence of (Flavones, Volatiles oils, Tannins, Saponines, Glycosides, Alkaloids,Resins and Terpenoids)in methanol80% crude extract. It can be concluded that the acetone and methanol crude leaf extract of A. vasicaNees can cause mortality in (nymphs, pupa) Bemisiatabaci, so it can be used asinsecticides.
Based on the density functional theory (DFT) , the stability of molecular complexes has been predicted according to hard-soft acid base (HSAB) theory. Relative stability of products and reactivity of soft base sulfide derivatives with halogens (Iodine , Bromine , Chlorine) as soft acid was studied to determine the relative ability of these reactants causing the reaction to be more spontaneous.
DFT at the levels of B3LYP/3-21G and B3LYP/3-21G (d) was used to study HOMO LUMO energy gaps , bonds length and total energy to calculate the softness sequence of each type of acid or base mentioned in this work. All cases studied prove that iodine can be considered as the most softness acid and ethyl methyl sulfide≈ dimethyl sulfide the most
Porous silicon (P-Si) has been produced in this work by photoelectrochemical (PEC) etching process. The irradiation has been achieved using diode laser of (2 W) power and 810 nm wavelength. The influence of various irradiation times on the properties of P-Si material such as P-Si layer thickness, surface aspect, pore diameter and the thickness of walls between pores as well as porosity and etching rate was investigated by depending on the scanning electron micrograph (SEM) technique and gravimetric measurements.
The following question was raised by L.Fuchs: "what are the subgroups of an abelian group G that can be represented as intersections of pure subgroups of G ? . Fuchs also added that “One of my main aims is to give the answers to the above question". In this paper, we shall define new subgroups which are a family of the pure subgroups. Then we shall answer problem 2 of L.Fuchs by these semi-pure subgroups which can be represented as the intersections of pure subgroups.
The ulma is one of the most spread social phenomenon.It occupies people in their different tendencies,the ulma imposes itself strongly in their social ,economic and politic sidies.
The problem of freedom quarrel is the older problem in creation .The groups as well as the individuals look for their liberty and it is restricted, they isolate themselves from others for a achieving it. Isolation phenomenon is one of common humanity phenomenon among individuals for looking of individuals psychological and social compatibility with other and society so they feel anxiety and tension and restriction of will and freedom. IT is known that college student from the major never in development and ren
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