نشریه شیمی کاربردی روز
پیاپی 14 (بهار 1389)

Conducting polyaniline (PANI) nano particles were synthesized by a sonochemical method and doped with HCl. The series of composites based on Polyaniline-Poly(styrene-alt-maleic acid) blended with Polystyrene sulfonic acid with different component content ratios were prepared by solution-dispersion blending method. The influence of Poly(styrene-alt-maleic acid)(PSMAC) and polystyrene sulfonic acid (PSS) on composite properties were investigated. The composite dispersed solution in tetrahydrofurane (THF) cast to fabricate conductive films. With only a mixing procedure and without any dispersant added, the PANI nanoparticles were well dispersed in the matrix polymer as indicated by scanning electron microscopy (SEM) images. The conductivity of obtained composites was measured with four probe technique. All of obtained composites have conductivity and between them, the maximum electrical conductivity was 2.86 S/cm. The obtained composites characterized by FT-IR and UV-Vis spectroscopy.

In order to study the heat effect of mixing of fresh waters (winter rains in the form of floods) with urmia lake water, the heats of mixing of urmia lake water with distilled water at 25ºC have been measured. On the basis of these experimental data, the Heats of dilution of fresh water in urmia lake water and urmia lake water in fresh water have been calculated. By considering the isothermal cycle of the dilution of urmia lake water, the partial heat of evaporation of water from urmia lake water was found to be ca. 2443.58 at 25ºC.

Dewatering of concentrates, tailings, etc. is an important process in most mineral processing operations. Flocculation is usually a necessary pretreatment step in many dewatering streams containing significant quantity of very fine particles. A large volume of research has gone in to optimising the use of various high molecular weight polymers as flocculants for fine particle suspensions.In this research, the effect of anionic polyacrylamide concentration as flocculant on velocity of settling is investigated. Flocculation experiments were conducted using the The kaolin suspension containing 5% solid (w/w) was first stirred thoroughly in a beaker. Then the requisite amount of flocculant was then added drop wise under continued stirring condition. The flocculation experiments were followed by sedimentation tests. The entire suspension after flocculation was transferred to a graduated cylinder and allowed to settle. A clear liquid– slurry interface could be seen descending. The height of this interface was noted at a regular interval of time. Settling rates at concentration of 2,4,6 and 8 ppm from flocculant were measured from the slope of the straight-line portion of the plot of interface height vs. settling time. By use of results, the optimum concentration of flocculant determined.

This paper describes the complexation of cobalt(II) with thiazolyl blue formazan in a micellar medium at the pH range 3 to10, using Spectrophotometric techniques. The influences of pH and surfactant amount have been also tested. The composition of the complex was determined by the continuous variation (Jobmethod) and mole-ratio methods. It was concluded that Co2+ forms a mononuclear 2:1 complex with thiazolyl blue formazan of the type CoL2- at pH = 6. Finally, the formation constants of the complex were evaluated at 25 ºC under ionic strengths ranging from 0.1 to 1 mol dm-3 of potassium nitrate.

Human can live without food and water for many days but they can not live without breathing Air more than a few minutes. Then, Air Pollution is a Problem that additional must attended. Many countries have developed search work and Programs to Control air pollution. There are a lot of industrial activities that lead to the trace element and particles in the air in Yazd city. This study was descriptive and Cross- Sectional. The amount of dust fall in the Air of Yazd was determined and also the amount of arsenic in dust fall was determined. In this study, The Sampling was done from 30 August 2009 to 10 March 2010 at four 1 month's Periods in Jomhuri bulvard, Homafar Square, Shahid Behesti Square, Seyd GoleSorkh Ave, and Aiatollah kashani Street by Jar method. The amount of Arsenic was determined by graphite furnace atomic absorption. The Maximum mean of Arsenic in dust fall was in the second Period equal to 10.677±3.133 μg/kg and the minimum mean of Arsenic was in the Fourth Period equal to 3.066 ±1.205 μg/kg. The maximum value was related to Jumhori Eslamic Bolvard equal to 15. 086 μg/kg and the minimum value was related to shahid Beheshti square equal to 1.134μg/kg. Comparison of means the P-value=.062 for different periods and the P-value=.389 for different station was obtained. These was shown that there is no meaningful difference between the Arsenic value in different periods and station. The maximum value of arsenic was observed in the second period of sampling, which is related to enhancement of traffic in city and decrease of air humidity. In addition, the maximum value was in Jumhori Eslamic Bolvard station that is due to existence of industrial factories of in these areas.

In this study, we report the synthesis and characterization of two new polypyridile Ruthenium Complexes, [Ru(Tttp)(opda-H2)Cl]PF6 and [Ru(Tttp)(en)(H2O)](PF6)2.3/2CH3CN. Complexes were characherized by 1HNMR, 13CNMR, IR and UV-Vis spectroscopies, Mass spectroscopy and elemental analysis. 1HNMR studies show that in [Ru(Tttp)(opda-H2)Cl]PF6, orthophenylenediamine is coordinated as (bqdi) or (s-bqdi) by loosing two hydrogen atoms, one from each amino groups. Electrochemiccal studies also show a redox potential at 1.55 V Vs. NHE which is duo to either RuII(bqdi)/RuIII(bqdi) or RuIII(s-bqdi)/RuIV(sbqdi) Reactions. Besides, another peak at -0.924 V is observed which due to either RuII(bqdi)/RuII(s-bqdi) or RuIII(s-bqdi)/RuII(s-bqdi). In the case of [Ru(Tttp)(en)(H2O)](PF6)2.3/2CH3CN, despite the usual coordination of chloro atom, a water molecule is coordinated. Electrochemical studies also reveal a redox peak at 1.66 Vs. NHE which is due to RuII/RuIV(O) redox reaction.

In today world water and water resources are considered as one of the most important properties. The main challenges for societies are to prepare food, water and energy. Among these it is somehow easier to provide food, because there are many ways to prepare it, also energy because of finding new resources, and it is only water that can make troubles for societies if there is no resource left. So planning for economizing the use of it and protection of available resources are of primary priorities. On the other hand occurrence of several droughts and increasing population growth, make the need for healthful drinking water. The water purification, better use of it in industry, water need in agricultural, the technological advances to use industrial, such as analytical methods in water purification and reducing the costs is inevitable. Some examples are chromatographic columns, resins, ion exchangers for softening, and reducing the hardness of water, and other processes such as chlorination, fluoridation, filtering and precipitation via advanced methods by using effective disinfection, advanced industrial methods and use of microprocessors to control the purification. In this connection purification processes in advanced countries are investigated such as United States. The advantages and disadvantages of mentioned methods are reported from different aspects. The result of such studies can provide us to use the new experiences in the world to use water Treatment technologies in Iran in order to prepare healthful drinking water and at the same time to reduce waste of time and expenses.