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This study aimed to clarify the legal implications of the check when it is empty of all or some of the mandatory formal conditions, and to indicate the optional conditions that may be included in the check . The optional conditions that may not be included in the check because they are inconsistent with its nature . The researcher concluded that the Jordanian legislator and the Iraqi legislator referred to the mandatory data in the check as an exclusive and not an example, by stipulating it in Article (137) of the Iraqi Trade Law and Article (228) of the Jordanian Trade Law. In particular, where the legislator arranged the invalidity of the check that is empty from the date of its creation. However, the check may include optional data that does not contradict with its nature and does not violate any of the peremptory rules or public order and public morals, and finally the researcher recommends the necessity to organize the optional data and indicate its importance, which does not conflict with the nature and essence of the check as is the case with the mandatory data, and not only referring to other articles provisions.

Infrared (IR) guided missile is known to cause 90% of aircraft damage. Magnesium/Teflon/Viton (MTV) decoy flares are customized materials, which are capable of yielding thermal signature to interfere with IR guided missile seekers. In this study, the IR-signature of an MTV flare is measured in a jet engine nozzle. The jet engine IR-signature is characterized with two characteristic peaks over the α-band (2–3 µm) and β-band (3–5 µm); this is correlated to black body emission at 690° C. The MTV decoy flare with 65% Mg offers an increase in the average intensity of the α- and β-bands by 21 and 4 times, respectively, to that of the jet engine. Quantification of emitting species in the combustion flame is conducted by using the ICT thermodynamic code. The developed MTV formulation offers the relative intensity ratio of the α- and β-bands equal to 0.96, which is comparable to that of an aircraft (0.7).

Modified DB propellants, based on energetic nitramine (RDX) were manufactured by solventless extrusion process. Thermal stability and shelf life assessment of modified DB propellant were investigated. Shelf life assessment was evaluated using Van't Hoff's formula and artificial aging at 70 °C up to 120 days. Quantification of total heat released and heat flow with aging time was conducted using differential scanning calorimetry (DSC) and thermal activity monitoring (TAMIII) respectively. Modified DB formulation based on 20 wt % RDX demonstrated enhanced thermal stability in terms of controlled heat flow, and slow decomposition reactions at elevated temperature. This formulation demonstrated extended service life up to 56 years compared with reference formulation. These novel finding was ascribed to the high thermal stability of RDX and its compatibility with DB constituents. This manuscript shaded the light on novel and effective approach for thermal stability via monitoring thermal activity with aging. Keywords: Double-base propellant, Thermal stability, Artificial aging, Shelf-life assessment

Colored flame compositions have distinctive variety of applications ranging from military signaling, rocket tracking, and illuminating devices. Certain elements and compounds when heated to high temperature are able to emit unique wavelengths in the visible region. This study, reports on the development of novel colored flames that cannot be generated by emitting atomic/molecular species. This was achieved by using chromaticity of basic colored flames. Mixing of high quality primary colored flames including Blue, Yellow, and Red in proper ratio was conducted; any interfering incandescent emission resulted from MgO was eliminated using Al metal fuel. The spectral characteristics in terms of luminous intensity, and color quality were evaluated using digital luxmeter and UV-Vis. spectrometer respectively. High quality mixed colored flames include violet, sweet pink, and marigold were developed. This study shaded the light on the state of the art for the real development of novel colored flame compositions and chromaticity of basic colored flames. Keywords: Pyrotechnics, Colored flame, Atomic spectroscopy, Molecular spectroscopy, Luminous intensity, Color quality, Chromaticity

Aluminum metal fuel, with combustion heat of 32,000 J/g, is of interest as high energy density material. Aluminum is able to react not only with free oxygen but also with inert combustion gaseous products. This study reports on the impact of ultrafine aluminum particles on combustion characteristics of double-base propellant. Metalized double-base propellant formulations were developed by solventless extrusion process. Combustion characteristics were evaluated using small-scale ballistic evaluation test motor. There was an increase in average operating pressure, burning rate, and characteristic exhaust velocity C∗ with aluminum content. Even though there was no oxidizer available for aluminum oxidation; aluminum alone offered 7.6% increase in average operating pressure, 24.6% increase in burning rate, 7.8% increase in C∗. The main outcome of this study is that this superior performance was achieved at 4 wt% solid loading level. Aluminum particles could alter the combustion wave by increasing the combustion flame temperature, average operating pressure inside the combustion chamber, thermal conductivity of DB propellant. All these combustion criteria could decrease the thickness of the dark zone, allowing the luminous flame to be more adjacent to the burning surface; therefore the reaction could proceed faster. Even though the developed metalized DB formulations were found to be more energetic with an increase in calorific value by 4.6%; they demonstrated good thermal behavior to reference formulation using DSC. These findings confirmed that aluminum is an outstanding energetic ingredient for solid rocket propulsion. It has unique ability to react with inert gases generating substantial heat output.

Double-base (DB) propellant is vulnerable to auto-catalytic decomposition reactions during storing with the evolution of nitrogen oxides. Modified DB propellant based on energetic nitramines (RDX) can offer enhanced thrust and action time. This study is devoted to evaluate the impact of RDX on chemical stability and shelf life of DB propellant. Extruded modified DB propellant based on RDX was manufactured by solventless extrusion process. Shelf life assessment was performed using an artificial aging at 70 °C up to 120 days and employing Van't Hoff's formula. Quantification of evolved NOx gases and stabilizer depletion with aging time was conducted using Bergmann-Junk test and HPLC respectively. Modified DB formulation based on RDX 20 wt % demonstrated enhanced chemical stability and extended service life up to 46 years compared with reference formulation. This finding was ascribed to the high chemical and thermal stability of RDX as well as its compatibility with DB constituents; no side chemical reactions could take place during storing. This manuscript shaded the light on RDX as effective energetic constituent that offered DB propellants with enhanced performance, good chemical stability, and extended service life. Keywords: Double-base propellant, Chemical stability, Artificial aging, Shelf life assessment

The burning rate-pressure relation of solid propellant is an exponential relation; this is means catastrophic combustion process in case of sudden increase in operating pressure. This study reports on novel approach to minimize the dependence of burning rate on combustion pressure using highly energetic nitramines (RDX). Nitramine-based double base propellants with RDX content up to 20 wt% were manufactured by solventless extrusion technology. The impact of RDX content on burning rate, specific impulse, exhaust velocity, and thrust were evaluated using small-scale ballistic evaluation rocket motor. Specific impulse (Is) was enhanced by 20%. The action burning time (tb) was increased by 14%. The total thrust impulse (IFT) was significantly improved by 22%. One of the main outcomes of this study is that burning rate pressure exponent (n) was decreased significantly from 0.35 to 0.05. This novel ballistic performance finding means minimal change in burning rate with pressure variation. These findings confirmed that RDX has a dual function as energetic filler and platonizing agent. RDX blowing effect could alter the combustion mechanism by pushing the luminous flame from the burning surface. Furthermore, RDX decomposition can strengthen the platonization action. This is the first time ever to report on burning rate platonization using RDX. It can be concluded that many advantages have been achieved with one shot.

Super-thermites can offer large amount of energy up to 16736 J/g. Flares based on super-thermites can offer superior thermal signature to countermeasure infrared (IR) guided missile seekers. This study reports on the sustainable fabrication of mono-dispersed Fe2O3 nanoparticles of 3 nm average particle size. Colloidal Fe2O3 nanoparticles were harvested from their synthesis medium and re-dispersed in acetone. Fluorocarbon polymers (teflon and viton) as well as aluminum metal fuel were integrated into Fe2O3/acetone colloid. The colloid mixture was granulated and mold pressed to develop the desired grain. The impact of Fe2O3 nanoparticles on thermal signature was assessed using (FT-MIR 1–6 µm) spectrometer. Flame propagation was investigated by video imaging of combustion wave. Combustion zones were quantified using image analysis. Quantification of flame temperature and main IR emitting species was performed using ICT thermodynamic code (virgin 2008). Nanocomposite flare with 12 wt% Fe2O3 offered an increase in the intensity of β band by 230% to that of reference formulation. The primary reaction zone was extended by 164%. Super-thermite particles not only offered superior spectral performance but also altered the combustion mechanism.

The burning rate-pressure relation of solid propellant is an exponential relation; this is means catastrophic combustion process in case of sudden increase in operating pressure. This study reports on novel approach to minimize the dependence of burning rate on the operating pressure using highly energetic nitramines (RDX). Nitramine-based double base propellants with RDX content up to 20 wt % were manufactured by solventless extrusion technology. The impact of RDX content on burning rate, specific impulse, exhaust velocity, and thrust were evaluated using small-scale ballistic evaluation rocket motor. Specific impulse (Is) was enhanced by 20 %. The action burning time (tb) was increased by 14 %. The total thrust impulse (IFT) was significantly improved by 22%. One of the main outcomes of this study is that burning rate pressure exponent (n) which was decreased significantly from 0.35 to 0.05. This novel ballistic performance means minimal change in burning rate with pressure variation. These novel findings confirmed that RDX has a dual function as energetic filler and as a platonizing agent. This is the first time ever RDX has been reported to act as a platonizing agent. It can be concluded that many advantages have been achieved with one shot.

Nanothermites are considered promising energetic materials and a key to develop new technologies in the field of energetics and propulsion. However, relatively low peak pressure, smaller thrust output, and incomplete combustion represent some of the potential problems associated with nanothermites. In this study to improve the combustion performance of nanothermites, varying quantities of nitrocellulose (NC) were introduced to produce the quaternary NC/GO/Al/KClO4 nanothermite using facile electrospinning. The morphology of nanothermites was characterized by SEM-EDX which confirmed that the nanoparticles were homogeneously dispersed without agglomeration. The combustion behavior of the composites was evaluated by igniting the samples at different packing densities (%TMD) in open acrylic tubes within a reaction chamber and using a 3.5 W continuous wave laser. High speed imaging captured the flame propagation and differential scanning calorimetry (DSC) was used to assess thermal behavior and energy output. Finally, for propulsion characterization, a small-scale test motor (STM) with a converging/diverging nozzle was used to evaluate the combustion performance of the prepared samples. In general, thrust output, specific and volumetric impulses (ISP and ISV), and total heat released exhibit remarkable enhancement with the addition of NC. Specifically, the total impulse (IFT) and ISP peaked at 5% NC/GO/Al/KClO4 at ~ 50% TMD, with IFT of 19.9 mN.s and ISP of 203.2 s. These are improvements of over 50% compared to the sample without NC (13.4 mN.s and 137.4 s). The ignition delay time and the power required to ignite the NC-enriched mixture is increased, but a sufficiently fast response is maintained for practical applications. Thermal analysis implies that addition of NC introduced another step to the GO/Al/KClO4 reaction: a gas− solid phase and liquid−liquid phase diffusion reaction, with the liquid−liquid phase reaction increasing with NC percentage. These results suggest that electrospinning is a simple technique for preparation of quaternary nanothermites that results in enhanced combustion performance and an improved suitability for small-scale propulsion applications.

Metal-based thermites, especially those based on aluminum, have been recently included in materials for energetic applications such as pyrotechnics, propellants, and explosives. In parallel, several advances in the field of Metal-Organic Frameworks (MOFs) and Coordination Polymers (CPs) have as well paved the road for their use in developing novel energetic materials. In this context, we are introducing new thermites compositions with low ignition temperature, stable propulsive force, and high reactivity. These thermites are based on the [Cu4Na(Mtta)5(CH3CN)]n (Mtta = 5-Methyl-1H-tetrazole) energetic metal-organic framework (EMOF-1) as a fuel instead of pure metals. We first report the synthesis of an energetic MOF via the microwave-assisted technique as a more rapid and greener method. The efficiency of composites based on EMOF-1 and Al together with various oxygenated salts were investigated. Multiple instruments are involved to characterize the morphology and the structure of EMOF-1 and the developed systems, such as SEM-EDX, FTIR, and XRD. The combustion behavior of the novel composites was evaluated by TGA/DSC, bomb calorimetry and laser ignition. Additionally, the apparent kinetic parameters (activation energy & frequency factor) were calculated by the Kissinger and Ozawa approaches. The results revealed that the new thermite mixtures exhibit superior combustion characteristics of one and half to two-folds the average heat of combustion compared to aluminum-based ones, at almost half the ignition temperature. In this sense, the combustion reaction proceeds faster, easier (reduced activation energy), the ignition temperatures are noticeably lowered, and the heat released has considerably improved. In addition, they exhibited stable force with longer burning time. Among them, EMOF-1/KIO4 thermite exhibits the highest heat release (4.7 kJ/g), while EMOF-1/NH4NO3 thermite shows the lowest onset reaction temperature (224 ᵒC). EMOF-1/KClO4 yields the highest average force (8.4 N), calculated pressure (1365 kPa), pressurization rate (0.32 kPa/μs) and the longest burning time assigned to EMOF-1/K2S2O8 (40 ms).

Much attention has been directed toward the development of modified double base (MDB) propellant as it can offer high specific impulse as well as wide range of burning rate. One of the main approaches for the development of MDB propellant is the integration of potential oxidizers and metal fuels. This study reports on, the impact of potential oxidizers including potassium perchlorate (KP) and ammonium perchlorate (AP) on combustion characteristics of double base (DB) propellant. The impact of these energetic additives on burning rate and the characteristic exhaust velocity of gaseous product (C∗) were evaluated using small-scale ballistic evaluation test motor. The two potential oxidizers KP and AP exhibited controversy effects; whereas KP positively impact the burning rate, AP positively impact C∗. The partial replacement of AP with aluminum metal fuel demonstrated a positive impact on both the burning rate and C∗. Aluminum metal fuel offered an increase the combustion temperature, and propellant thermal conductivity. Consequently, it could alter the combustion mechanism, by thinning the induction zone, allowing the luminous flame zone to be more adjacent to the burning surface. Accordingly, the combustion reaction could proceed faster. While, MDB based on AP/Al were found to be more energetic with an increase in calorific value to reference formulation using bomb calorimetery; they exhibited good thermal stability in terms of ignition temperature using cook off test, and accepted thermal behavior using DSC.

Composite modified double-base propellants (CMDB) are characterized with high energy output, wide range of burning rates, as well as enhanced ballistic performance. Recently, much attention has been directed toward the development CMDB. One of the main approaches for the achievement of CMDB includes the integration of an effective oxidizers and fuels, in an attempt to maximize the output heat. This study reports on the effects of potential oxidizers including potassium perchlorate and ammonium perchlorate on the ballistic performance, particularly burning rate, of double base propellant. The ballistic parameters of several CMDB formulations were investigated using a chemical equilibrium computer program named ICT Thermodynamic Code (Institute of Chemical Technology in Germany, virgin 2008). Theoretically, there was an increase in specific impulse with the increase of potassium perchlorate (KP) and ammonium perchlorate (AP) content up to 20 wt.%. CMDB formulations based on different wt. % of KP and AP up to 10 wt. % were manufactured by extrusion process. The practical ballistic performance was evaluated using static test (small scale one inch rocket motor). The two oxidizers exhibited controversy effect. The burning rate was increased by 22 % with the addition of 10 wt. % KP; whereas the characteristic exhaust velocity (C*) was increased by 5.3 % with the addition of 10 wt. % AP. This paper might open the route for the manufacture of CMDB with tailored enhanced performance in terms of specific impulse and burning rate.

This thesis tries to propose a list of Critical Success Factors (CSFs) in the form of CSFs framework for Enterprise Resource Planning (ERP) system implementation at Small and Medium sized Enterprises (SMEs).The research describe in this thesis tries to test them by going through the experience of ERP system implementation in SME called Hazelwood Sound & Vision Ltd (HSV). In a first instance, the author compared implementation models and suggested most appropriate model for HSV. Furthermore, literature search for critical success factors of ERP implementation has taken place. This led to a general CSFs framework for ERP system implementation. At later stage, CSFs were classified into the phases of selected implementation model. This resulted in integrated framework which later used for ERP system implementation called Smart Office in HSV. Through this experience of implementing Smart Office in HSV, the author determined factors which were critical for the success of the ERP implementation in HSV and compared them with CSFs found in literature. The study also examines, through the critical success factors, the impacts and issues in implementation related to these factors. Findings include: an increased emphasis upon the determination of clear goals and objectives at the project outset, and, importantly, vendor support added value in terms of specialist software knowledge and enhanced project team capability. Results show that most of the success factors, found in the literature apply to HSV, although change management, and communication among departments, don‟t seems to be regarded as top CSFs for HSV. Implementation is an expensive investment, and difficult to implement, due to its complexity. It is hoped that knowledge and understanding of these factors will assist SMEs in successfully implementing ERP and enable them to further improve their systems in order to maximize returns. Furthermore, by identifying relevant CSFs for SMEs, managers can better prioritize implementation efforts and resources to maximize success of ERP implementations. One of the outcomes of this research is implementation of Smart Office which fulfils the business needs of the HSV.