The photostabilization? of poly vinyl chloride (PVC) ? films has been investigated by using diamine derivatives. The? (PVC) films were? contained 0.5% weight? of diamine derivatives which prepared by the method of casting. The photostabilizations? ?of these compounds were determined by monitoring the carbonyl index value with irradiation time. Also, the effect ?of concentrations of additives (range 0.1-0.5wt) on the rate of photostabilization? process was studied. Therefore we found? that a increased photostabilization rates was increase with increasing? concentrations of compound. Besides, the influence? on film thickness? of photostabilization process was also studied; ?and the results? showed that? the increasing of film thickness increase the rate of photostabilization. Also, the changes in the viscosity? of the averagee molecular weight, the degree? of deterioration (?) and the average number of chain scission (s) were tracked, it was concluded? that the random chain scission is always occurs in PVC film, also Quantum yield? of the chain? scission of? these compounds? was calculated. Several mechanisms? have been? suggested and according to experimental results obtained, these mechanisms are dependent on the structure? of? the additive, Among UV absorper? and radical? scavenger.
in this paper the collocation method will be solve ordinary differential equations of retarted arguments also some examples are presented in order to illustrate this approach
In this paper, an Integral Backstepping Controller (IBC) is designed and optimized for full control, of rotational and translational dynamics, of an unmanned Quadcopter (QC). Before designing the controller, a mathematical model for the QC is developed in a form appropriate for the IBC design. Due to the underactuated property of the QC, it is possible to control the QC Cartesian positions (X, Y, and Z) and the yaw angle through ordering the desired values for them. As for the pitch and roll angles, they are generated by the position controllers. Backstepping Controller (BC) is a practical nonlinear control scheme based on Lyapunov design approach, which can, therefore, guarantee the convergence of the position tracking
... Show MoreDifferent additives are used in drilling fluids when the demanded properties cannot be gotten with clays. Drilling muds needs several additives and materials to give good characteristics. There are local alternatives more suitable for enhancing the rheology and filtration of drilling fluids. An experimental work had been conducted to assess the suitability of using potato starch to enhance rheological properties and filtration in drilling mud. This study investigated the potato starch as a viscosifier and fluid losses agent in drilling fluid. Results from this study proved that rheological properties of potato starch mud increased when pH of drilling fluid is increased. Potato starch could be used to enhance gel strength at low pH
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An optoelectronic system for fog detection and visibility technique is presented .The idea of this research is based on the measurement of the atmospheric visibility by using an infrared beam emitter from LED diode. The optical scattering is used as a method to calculate the visibility. This method is applied at forward scattering within a foggy atmosphere, which is modern and has great importance for measuring visibility in seaports, airports, public roads and highways. In this paper we focus on the description of the system, principles of its operation and some results of field tests.
Keywords: fog sensor, visibility sensor, backscattering, forward scattering.
Abstract: Israel formulated its security theory, which it established on the "pretext of war", meaning converting any Arab action that Israel deems a threat to its security, into a pretext to ignite the fuse of war, considering this a violation of an existing situation, and then it initiates preventive and pre-emptive attacks, then immediately turns into transfer the war to the enemy's land, to achieve a quick solution by (destroying the enemy), occupying its lands, and benefiting of the advantage of working on (internal lines against an enemy) working on external lines, and ending the war quickly, before the major powers intervene to impose a ceasefire
This study was designed to show the advantages of using the combination of metformin and rosiglitazone over using each drug alone in treatment of women with polycystic ovary syndrome (PCOS).Forty four women with PCOS were classified into 3 groups , group 1 received rosiglitazone (4mg/day) for 3 months , group ΙΙ received metformin ( 1500 mg/day)for three months and groupΙΙΙ received the combination ( rosiglitazone 4mg/day + metformin 1500 mg/day) for the same period of treatment . The blood samples were drawn before treatment and after 3 months of treatment . The fasting serum glucose , insulin , progesterone , testosterone , leutinizing hormone were measure
... Show MoreLet/. It :0 ---0 G be any two self maps of a compact connected oriented Lie group G. In this paper, for each positive integer k , we associate an integer with fk,hi . We relate this number with Lefschetz coincidence number. We deduce that for any two differentiable maps f, there exists a positive integer k such that k 5.2+1 , and there is a point x C G such that ft (x) = (x) , where A is the rank of G . Introduction Let G be an n-dimensional com -pact connected Lie group with multip-lication p ( .e 44:0 xG--+G such that p ( x , y) = x.y ) and unit e . Let [G, G] be the set of homotopy classes of maps G G . Given two maps f , f G ---• Jollowing [3], we write f. f 'to denote the map G-.Gdefined by 01.11® =A/WO= fiat® ,sea Given a point g
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