In this study, NaOH dissolution method was applied to dissolve cellulose fibers which extracted from date palm fronds (type Al-Zahdi) taken from Iraqi gardens. In this process, (NaOH)-solution is brought into contact with the cellulose fibers at low temperature. Experiments were conducted with different concentrations of NaOH (4%, 6%, 8% and12%) weight percent at two cooling bath temperatures (-15 oC) and (-20oC). Maximum cellulose dissolution was 23 wt% which obtained at 8 wt% concentration of NaOH and at cooling bath temperature of -20oC. In order to enhance the cellulose fibers dissolution, the sample was pretreated with Fenton's reagent which consists of hydrogen peroxide (H2O2), oxalic acid (C2H2O4) and ferrous sulfate (FeSO4). This reagent reacts with cellulose fibers and produces free radicals which increase cellulose dissolution. In this work three variables were studied: cooling bath temperature (-15oCand-20oC), NaOH concentration (4%, 6%, 8% and12%) and time of Fenton's reagent treatment (1-48) hrs. The results showed that the best percent of cellulose dissolution was (42 wt %) which occurred at treatment time (24 hours), temperature (-20oC) and NaOH concentration 8%. In another set of experiments urea was added to NaOH solution as a catalyst with proportion (6%NaOH+4% urea) at two temperatures -15 and -20 oC. The results show that the solubility of cellulose increase to 62% for the sample which treated with Fenton's reagent and to 35% for the untreated sample, both values were obtained at -15oC.
Background: The access cavity is a critical stage in root canal therapy and it may influence the subsequent steps of the treatment. The new minimally invasive endodontic access cavity preparation concept aims to preserve sound tooth structure by conserving as much intact dentine as possible including the pulp chamber's roof, to keep the teeth from fracturing during and after endodontic treatment. While there is great interest in such access opening designs in numerous publications, still there is a lack of scientific evidence to support the application of such modern access cavity designs in clinical practice. This review aims to critically examine the literature on minimal access cavity preparations, explain the effect of minimally inva
... Show MoreRegulations of changes in Sharia policy
Variables include jurisprudential rulings that may be subject to change, alteration and interpretation, depending on the mujtahid’s view of the ruling, or changing it and switching to another view, and the variables are the crucial issues that befell the nation of Islam. It was not neglected by Islamic legislation, but rather the setting of controls that took into account in every incident the norms, interests and purposes.
The art of pantomime mime is one of the arts that has taken a wide space in theater performances, and because it is one of the spectacle shows that relies on an acting performance that is unique from the traditional acting performance, because of the peculiarity of pantomime art in that it is a silent performance that assumes the clarity of meaning, and for the purpose of clarifying the actor’s work in such kind of performances, the art of pantomime must be We have to know the skills that the actor can possess in order to produce a silent show that has the elements of a successful presentation, so there was a need to study the skills of the actor in this type of acting performance. The researchers divided this study into an introductio
... Show MoreCognitive radio is observed as a new approach, which could be cope with the spectral limitations. This approach is designed to detect whether a particular segment of the radio spectrum is currently in use and to jump into the temporarily unused spectrum rapidly without interfering with the transmissions of other users. CR is the promising radio technology which aims to detect and utilize the temporally unused spectrum bands by sensing its radio environment in order to improve spectrum utilization. To enhance the sensing performance, cooperative spectrum sensing has been proposed. However, when the number of cognitive user tends to be very large, the bandwidth for reporting sensing results to the common receiver will be very huge. In this pa
... Show MoreBackground: Ameloblastoma is the most common clinically significant odontogenic tumor, known for its locally invasive potential and frequent recurrences unless treated radically. Endocan is a soluble proteoglycan which is reported to have prognostic implications in multiple human diseases and tumors. This study aims to describe the expression of endocan in ameloblastoma. Materials and methods: With immunoperoxidase method; tissue sections of formalin fixed- paraffin embedded blocks for ameloblastomas were stained with monoclonal antibodies to endocan, the localization of the endocan expression was examined and the resulting scores of the tissue sections were analyzed according to age, sex, site and tumor subtype. Results: endocan was found
... Show MorePresupposition in Fitzgerald the Rough Crossing
This study Arabic dialect prevailing in the province of Khuzestan [southwest Islamic Republic of Iran] as one of the Arabic dialects abundant qualities and characteristics of linguistic entrenched in the foot, which includes among Tithe thousands composed of vocabulary and structures and phrases classical that live up to the pre-Islamic era, if what Tasha researcher and reflect accurately the find of a large number of phrases and vocabulary and acoustic properties by nature accent, and formal, and nature of the synthetic, and characteristics semantic and contextual in this dialect studied without being something of them heavy on the tongue and without displays her tune or Tasha or distortion and so on all of which constitute a catalyst i
... Show MoreMelatonin, a hormone synthesized mainly by the pineal gland, has been found in extra-pineal organs as well. It’s known as an organizer of circadian rhythms and more recently as an anti-oxidant. In addition to its role in maintaining immunity, pathophysiology of cardiovascular and neurological diseases, and as an anti-cancer agent, evidence has demonstrated that melatonin exerts a positive impact on male and female fertility primarily through oxygen scavenging effects. In In Vitro Fertilization (IVF) programs, supplementation of melatonin may be associated with better outcomes in terms of sperm quality, oocyte quality, embryo quality and pregnancy rates. This review summarizes various actions of melatonin on the body focusing on male an
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