Phosphate ester compounds display good flame retardancy effect in epoxy resin systems. In this paper, several novel phosphate esters, used as curing agents for epoxy resins, were synthesized based on P2O5, phosphoric acid, and different types of alcohol. The structures of phosphate esters were characterized by 31P nuclear magnetic resonance (31P NMR). Then, a series of flame retardant epoxy composites were prepared by curing the epoxy resins (E-44) with the phosphate esters. The flame retardancy and thermal degradation behaviors of flame retardant epoxy composites were investigated by cone calorimeter test (CCT) and thermogravimetric analysis (TGA), respectively. The results of CCT indicated that phosphate esters can significantly decrease heat release rate, total heat release (THR), and smoke production rate. The sample cured by butyl phosphate ester from phosphorus pentoxide, phosphoric acid and butanol showed the best flame retardant performance among all samples. The TGA results showed that phosphate esters could enhance char residues of flame retardant epoxy composites when compared with those of a composite using T31 as a curing agent at high temperature. It may be concluded that good flame retardant properties of flame retardant epoxy composites are related to the formation of a protective phosphorus-rich char layer. These phosphate esters have a good future on flame retardant epoxy composites.

Deprotection of phosphate, phosphite, and sulfite esters by silica chloride is described. Silica chloride is a mild, selective, and effective reagent for cleavage of benzyl and t-butyl esters of the above compounds.

In this study, various amounts of clay nanoparticles and titan nanoparticles (1, 3 and 5% wt.) were introduced into a vinyl ester resin matrix by high shear mixer. The influence of these nanoparticles on the mechanical properties (tensile strength, tensile modulus, flexural strength, flexural strength and fracture toughness) is investigated. To investigate the structure of nanocomposites, X-ray diffraction (XRD) and transmission electron microscopy (TEM) tests are done. The XRD test shows that the structure of clay-vinyl ester nanocomposites is exfoliated. The results of tensile, flexural and fracture toughness experiments show that clay is better than titan in the improvement of the mechanical properties. Clay- vinyl ester nanocomposite with 1% wt. of clay has the better mechanical properties than others samples.

In This Paper, LM Pectin Production from Commercial apple Pectin By Using Acid, Alkali And Ammonia Methods In The Presence Of Ethanol Was Studied. Also, The Effect Of Different Parameters Such As, Temperature, Time, Acid, Alkali And Ammonia Treatment In LM Pectin Production Were Evaluated. In All The Experiments, Low Temperature Showed A Better Influence From A Recovery, Purity And Low De-Polymerization Viewpoint. Optimum Conditions In The Acid Method Reached At Ph = 2, T = 17 Hrs And T = 30°C, In The Alkaline Method Reached At Ph = 11, T = 3 Hrs And T = 5°C And In The Ammonia Method Reached At 2 N Ammonia And T = 5°C, Were determined.

Objective Compared to other primary photosynthetic products (such as sucrose and starch), little is known about sugar metabolism and how it is integrated with others. Mannose-6-phosphate reductase (M6PR) is a key enzyme involved in mannitol biosynthesis in celery. This study aimed to clone the gene, express and purify the M6PR enzyme and investigate its function on mutated genes in a laboratory environment. Materials and methods First, the mRNA was extracted from the celery plant, then the cDNA was synthesized, and the product was used as a template to amplify the M6PR gene. The PCR product was purified in a DNA gel extraction kit. The purified PCR product was cloned into the pTZ57R vector according to the T/A Cloning recipe (Fermentase Company). Susceptible cells of E.coli strain Top10 were prepared using the biochemical method of calcium chloride, and the recombinant vector inside it was transformed and cultured on a plate containing ampicillin. The cloning accuracy was done using M6PR gene PCR and enzymatic digestion of the recombinant plasmid by BamHI and SacI enzymes (Fermentase Company). The M6PR gene was homogenized in the expression plasmid pET32a and transferred into E.coli strain BL2I. The promoter was induced with IPTG and analyzed by western blotting. The protein was purified by affinity chromatography column (His. Tag/S.Tag). Results The results showed that the enzyme could identify the heteroduplex regions of the gene. The recombinant M6PR purified from Escherichia coli had specific molecular activity. The results of double digestion of the plasmid with SacI and BamHI enzymes were 2870 bp and 186 bp fragments. According to the blast test result, the current fragment had 100% similarity with the M6PR gene of the celery plant. M6PR recombinant gene transcription results showed that the M6PR recombinant gene transcription rate was 2.3 in the transgenic strains and 0.32 in control, which showed a statistically significant difference at the P<0.01 level. After induction of the promoter and sampling at different times, the samples on the SDS-PAGE gel showed a protein band in the region of 42 kDa, indicating the protein's successful expression. Conclusions Homology of M6PR enzyme gene obtained from celery plant and then recombinant production of this enzyme in the laboratory can lead to its high expression in the prokaryotic system so that the enzyme has activity. Also, the present study showed that plant enzymes are active when expressed in bacteria and can be used as a suitable source to accelerate catabolic activity.

Background and objective: Air pollution by dust of the main problems in the country's West Frontier that is effective role on general health of residents. The presence of bacteria in the air and dust and their harmful effects on human health have been reported in various studies. This study is done to identify the bacteria natural air (free from dust) to dust polluted and compare both the number and diversity of their environment by FAME technique.Materials and methods: samples of natural air and dust contaminated with Particle deposition method on the plate or gravity and using sterile petri plates containing nutrient medium BHI Agar from 5 points in the city in 15 and 30 minutes was conducted in the summer. Plate transported to the laboratory and was incubated at 37oC for 24 to 48 hours. After the growth of bacterial colonies using biochemical tests and techniques FAME Bacterial colonies grown on the medium was studied and identified.Results: A total of 1114 bacterial colonies were counted on 30 plates collected from 5 locations. With Gram staining methods, MacConkey agar medium and Biochemical tests of 13 different bacteria were identified. In the dust air of the city of Ilam at 15 and 30 minutes most of the genus Rhodococcus (15 minutes) and Bacillus (30 minutes). From1114 colonies were counted; the number of 170 colonies of natural air and 944 colonies was dust in the air. The results showed that the highest number of bacteria has been gram-positive cocci in natural air and gram-positive bacilli in the dust air and was not observed pathogenic bacteria in natural air and dust.Conclusion: The results showed that due to the high number of bacilli and spores bacteria in the air of dust are more resistant to adverse environmental conditions and that thereby the survival of most of them.

Calcium phosphate cements (CPCs), using B-tricalcium phosphate (ß-TCP, Ca3 (P04)2), dicalcium phosphate (DCP, CaHP04), calcium carbonate (Ca CO3), and hydroxylapatite (HAp, Ca10(P04)6(OH)2) as powder cement and disodium hydrogen phosphate (Na2HP04) solution as liquid component were prepared. After mixing the powder and liquid constituents, injectable and self-setting calcium phosphate cements (CPCs) were prepared with different liquid to powder ratios (UP) that formed hydroxylapatite and ß-tricalcium phosphate as the only end products, which were characterized by FTIR, XRD and SEM techniques. The results showed that, at certain concentration of Na2HP04 (6 wt%), the initial and final setting times decreased by decreasing the UP ratio.