The catalytic activity of faujasite type NaY catalysts prepared from local clay (kaolin) with different Si/Al ratio was studied using cumene cracking as a model for catalytic cracking process in the temperature range of 450-525° C, weight hourly space velocity (WHSV) of 5-20 h1, particle size ≤75μm and atmospheric pressure. The catalytic activity was investigated using experimental laboratory plant scale of fluidized bed reactor.
It was found that the cumene conversion increases with increasing temperature and decreasing WHSV. At 525° C and WHSV 5 h-1, the conversion was 42.36 and 35.43 mol% for catalyst with 3.54 Si/Al ratio and Catalyst with 5.75 Si/Al ratio, respectively, while at 450° C and at the same WHSV, the conversion was decreased to 29.15 and 21.86 mol% respectively, and the catalyst of 5.75 Si/Al ratio gave the higher cumene activity than the catalyst with 3.54 Si/Al ratio.
When optimizing the performance of neural network-based chatbots, determining the optimizer is one of the most important aspects. Optimizers primarily control the adjustment of model parameters such as weight and bias to minimize a loss function during training. Adaptive optimizers such as ADAM have become a standard choice and are widely used for their invariant parameter updates' magnitudes concerning gradient scale variations, but often pose generalization problems. Alternatively, Stochastic Gradient Descent (SGD) with Momentum and the extension of ADAM, the ADAMW, offers several advantages. This study aims to compare and examine the effects of these optimizers on the chatbot CST dataset. The effectiveness of each optimizer is evaluat
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The charge species plays a vital role in changing the field in direct current discharge (DC). This article introduces a numerical modeling in one dimension of the inner electrode diameter of oxygen-fed negative corona discharge in coaxial electrodes geometry. The properties of negative corona plasma in a concentric cylindrical electrodes (wire-cylinder) were simulated by COMSOL Multiphysics software. Various diameters of negative corona electrode, namely 0.01, 0.025, 0.05, 0.075, and 0.125 mm, were applied, where the diameter of the outer cylindrical electrode was taken as 15 mm. The model was run at atmospheric pressure and the applied negative voltage was
-10 KV. Moreover, oxygen gas was used to fill the inter-electrodes dist
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The vision and philosophy of the economic system in Iraq after 2003 were not clear-cut because of overlapping internal factors was the novelty of the political system and the lack of political and economic decision makers to understanding and conviction full need shaping a new administration for the Iraqi economy is able to succeed economic development programs, and external factors was determinedly organizations international application of shock reforming style and contrary to the social reality and the security which reflected negatively on the work and consistency Lisseeash financial balance between stability and growth and raise the level of consumer spending and the importance of r
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Background: proteins, glycoproteins and fructose as parameters used to assess infertility in men.
Objective: To determine and correlate serum and seminal plasma of total proteins, glycoproteins and fructose with infertility in men.
Patients and Methods: The study was performed on 154 subjects; 109 infertile men (oligospermic and azoospermic) and 45 normal volunteers (normospermic men). All sera and seminal plasma were submitted for total proteins, glycoproteins and fructose levels measurment.
Results: No significant difference was noted in serum and seminal plasma of total proteins in oligospermic and azoospermic and that of normospermic men (P>0.05) compared to normospermic men. Statistical sign
In this paper, Nordhaus-Gaddum type relations on open support independence number of some derived graphs of path related graphs under addition and multiplication are studied.
Abstract
The research problem focuses on studying the interest of the Medical City Department of the Ministry of Health in improving the creative thinking skills of the administrative leadership through parallel & comprehensive thinking according to the of six thinking hats strategy. The research sample consisted of (170) administrative leaders in the upper & middle organizational levels, The questionnaire was used as a main tool for data collection, In addition to the observation & Interview, The research sought to answer the following questions: What is the extent to which the administrative leadership (Tpp & middle) in the organization investigated the concept of the six thinkin
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Th r:ats for the photo induced eleytr-on tra;nsfer reactions in the
Methylen-e blue 'l'vffi+ ·dye· with benzo_phenone (ABP) ketone in variety
solvc;:nts al n:loin tempemtme ha;ve qn calculated . Electron trans_ fer
-rates are large in• }stt:on;gly--'{:'lolaf- solvent and week in-l s.s :polar solvent.
the high values o:E t±te r.tes a_f electro-n tr;ans-fer indicate that tite dye
triplet i$ mqre, r activ.e toWard ABP ket-one.
Ninety nine swabs were collected from patients with diabetic foot ulcers (DFU), all swabs were cultured on different selective media for screening, 46 isolates confirmed as S. aureus by API staph. The results of antibiotic susceptibility test revealed that all isolates were resistant to metronidazole, 34 isolates were resistant to cefoxitin, ceftriaxone, and meropenim, 23 isolates were resistant to ciprofloxacin and norfloxacin, 17 and 16 isolates were resistant to tetracycline and trimethoprim, respectively; while all isolates were sensitive to tigecycline. The results of minimum inhibitory concentration (MIC) that carried out by using vancomycin, tigecycline and linezolid for 8 isolates, MIC results were1-2 µg /ml
... Show MoreThis study deals with free convection heat transfer for the outer surface of two
cylinders of the shape of (Triangular & Rectangular fined cylinders with 8-fins),
putted into two different spaces; small one with dimension of (Length=1.2m,
height=1m, width=0.9m) and large one with dimension of (Length=3.6m, height =3m,
width=2.7m). The experimental work was conducted with air as a heat transport
medium. These cylinders were fixed at different slope angles (0o, 30o, 60o and 90o)
.The heat fluxes were (279, 1012, 1958, 3005, 4419) W/m2, where heat transferred by
convection and radiation. In large space, the results show that the heat transfer from
the triangular finned cylinder is maximum at a slope angle equals
Background: The longevity of any prosthesis depends on the materials from which it was fabricated, that is why, defects in the material properties may reduce the service life of prosthesis and necessitate its replacement. The aim of this study was to evaluate the effect of adding different concentrations of Polyamide-6 (Nylon-6) on the tear and tensile strength of A-2186 RTV silicone elastomer. Materials and Methods: 80 samples were fabricated by the addition of 0%, 1%, 3% and 5% by weight PA-6 micro-particles powder to A-2186 platinum RTV silicone elastomer. The study samples were divided into four (4) groups, each group containing 20 samples. One control group was prepared without PA-6 micro particles and three experimental groups were pr
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