در این تحقیق بهینه‌سازی فرآیند استخراج عصاره چای سبز با هدف بیشینه کردن بازده استخراج مواد جامد و کمینه نمودن کدورت نمونه توسط روش سطح پاسخ انجام گرفت. اثرات دو فاکتور دمای فرآیند استخراج در سه سطح دمایی 40، 70 و 100 درجه سانتی‌گراد و مدت زمان استخراج عصاره در سطوح 5، 62/5 و 120 دقیقه با کمک طرح مرکب مرکزی بر روی پارامترهای بازده استخراج مواد جامد و کدورت بررسی گردید. بررسی نتایج نشان داد شرایط...

Investigation shows that the some complex and expanded parameters are effective on the burning rate. In this paper we evaluate the effect of particles dispersion, size of AP particle, the size of Al particles, Fe2O3, viscosity, shape factor, the size of mixer and the mechanical parameters such as tensile and stress on the burning rate. These studies show that the decrease of AP particles, size ...

In this paper, diffusion and migration of Dioctyl sebacate (DOS) and Dioctyl phetalate (DOP) plasticizers at the interface of propellant and insulation as well as different distances from the interface in composite solid propellant based on HTPB / AP using both experimental and modeling have been investigated. Solid composite propellant and Nitrile Butadiene Rubber (NBR) insulation containing D...

Hydroxyl terminated polybutadiene (HTPB) is the most commonly used binder in composite solid propellants. However, due to its non-energetic character, in practice it is just a dead weight; Therefore, replacing HTPB with an energetic polymer is essential. In this research, nitrated hydroxyl terminated polybutadiene resin (NHTPB) with 12.2% nitration rate, in combination with HTPB resin was used ...

The success of the composite solid propellant motor depends on the proper stress-strain behavior of the propellant grain against tensile, compression and shear stresses and intensive changes in gravity during launch. In this paper, the effect of formulation components and other parameters affecting mechanical properties (tensile strength, elongation and elastic modulus), and their effects AP/Al...

هدف از این تحقیق، بهینه سازی استخراج کلروفیل از برگ درخت شاتوت با استفاده از روش فراصوت بود. برای بهینه سازی اثر شدت توان فراصوت (10-100%) نسبت حلال به ماده جامد (5-10 میلی گرم بر لیتر)، دما (30-70 درجه سانتیگراد) و زمان (2-10 دقیقه) بر بازده کلروفیل کل و شاخص سبزی از طرح مرکب مرکزی با شش تکرار در نقطه مرکزی استفاده شد. نتایج بهینه سازی نشان داد که مدل درجه دوم برای بازده کلروفیل کل معنی دار بو...

In this paper, the factors effecting the shock wave and impact Sensitivity such as oxygen balance, porosity, components particle size in composite solid propellants have been investigated. The energetic components of propellants such as oxidizer and fuel usually effect shock wave sensitivity and changing in composition, particle size and manufacturing process, determine the sensitivity property...

GAP propellants has good performance due to high energy of this polymer. Unfortunately, due to poor flexibility of GAP polymer and presence of rigid and conjugated azide side groups in its structure, they have poor mechanical properties especially under low temperatures. This article deals with methods of improving mechanical properties of solid composite propellants based on GAP through changi...

Abstract In this study, the effect of additives such as ammonium oxalate (AO), mixture of ammonium oxalate and strontium carbonate (SC) on AP/HTPB based composite propellants was investigated by burning rate, DTA, density and autoignition temperature measurements. The results show that the burning rates of these propellants are decreased significantly. DTA and autoignition temperature experime...