نتایج جستجو برای: gel time
تعداد نتایج: 1982027 فیلتر نتایج به سال:
Currently available polymers as a component of in-situ gels are unsuitable for treating high-temperature/high-salinity reservoirs due to their chemical and thermal degradation. In this study, a new copolymer-based gel system including high molecular weight nanostructured polymers (NSPs) was developed to address the excessive water production problem in reservoirs under harsh conditions. The sta...
Background: There are various methods to read out responses of a polymer-gel dosimeter, among which the Magnetic Resonance Imaging (MRI) technique is the most common one. Optimizing imaging protocols can have significant effect on the sensitivity and the dose resolution of polymer gel dosimeters. This study has investigated the effects of the number of echoes (NOE) and the echo time spacing (ES...
sol-gel and polymeric membrane electrodes, based on thiacalix[4]arene as a neutral carrier, weresuccessfully developed for the detection of vo2+ in aqueous solutions. the sol-gel and pvcmembrane electrodes exhibited linear response with nernstian slopes of 29.3 and 28.4 mv perdecade, respectively, within the vanadyl ion concentration ranges from 1.0 × 10-6 to 1.0 × 10-1mol dm-3 and from 1.0 × 1...
چکیده مقدمه: استفاده از زیرکونیوم به عنوان کور در ساخت روکش های دندانی با توجه به استحکام بالا، تطابق بافتی و در عین حال زیبایی آن موجب ارتقای پروتز های ثابت شده است. با این حال یکی از مشکلات اساسی در استفاده از روکش های بر پایه زیرکونیوم، تمایل کم زیرکونیا برای واکنش شیمیایی با پرسلن و سمان و در نتیجه باند ضعیف آن می باشد که موجب مشکلاتی از قبیل پریدگی و جداشدگی پرسلن می شود. هدف از مطالعه ح...
Epoxy – Polysulfide copolymers without or with low amounts of epoxy in their structure have poor mechanical properties in oxidative curing system.To strengthen the mechanical properties of polysulfide elastomer inclusion of epoxy resin (Epon828) as hard segment was studied. FT-IR spectroscopy and rheometry were used to verify the formation of epoxy-polysulfide copolymer. Results obtained f...
gelled propellants are improved propellants that can be considered as the final extension of liquid propellants. high specific impulse, good density and safety better than that of both solid and liquid propellants are advantages of the gel propellants. they are made by addition a suitable gellant to liquid propellants. in this research, nano al particles have been used in udmh gel fuel. the gel...
Agar extraction for Gracilaria corticata by investigating the effects of various extraction variables such as soaking time, soaking temperature, seaweed to water ratio, extraction temperatures and extraction time and also Alkali treatment method. The results showed that agar yield was significantly affected by all the tested variables. The agar yield was maximized when extraction process was ca...
OBJECTIVE This study aimed to compare intubation performance between blind intubation through supraglottic airway devices and direct laryngoscopy by novices under manikin simulation. We hypothesized that the intubation time by novices using supraglottic airway devices was superior to that with the Macintosh laryngoscope (MCL). METHODS A prospective, randomized crossover study was conducted wi...
abstract in aggregate, active forms of reactive silica with mineral names are sometimes associated with sand and gravel in concrete mixture. alkali hydroxides originated from alkalis in the cement or other resources form an alkaline silica gel with this reactive silica which becomes swallowed and expanded during time causing damage to concrete. there have been growing researches on alkaline r...
نمودار تعداد نتایج جستجو در هر سال
با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید