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This paper studied the use of bifunctional ionic liquid, [Trialkylmethylammonium][Di-(2-ethylhexyl) Phosphate] as an extractant to extract and separate samarium-europium-gadolinium mixed solutions. The extractant combined the conventional extractant di-(2-ethyl hexyl) phosphate (DEHPA) with ionic liquid Aliquat 336 (A336) through acid/base neutralization method. This study focused on optimizing the extraction process via common one-factor-at-a-time (OFAT) method and response surface methodology (RSM) using statistical design. The parameters involved were the effect of acid (hydrochloric acid, sulfuric acid and nitric acid), acid concentration (1.5-5.0 M) and percentage of organic to aqueous phase (50%, 60%, 70%, 80%, 90%) to determine the separation factor of each metals. Using OFAT the best condition was 3.0M HNO3 in 80% organic for separation of samarium with βSm/Eu+Gd =2.91. For separation of europium/gadolinium the highest separation factor achieved was βEu/Gd=3.44. In comparison, the optimum condition based on RSM able to elevate the separation factor of βSm/Eu+Gd to 3.17 and βEu/Gd to 3.75. [ABSTRACT FROM AUTHOR] more...

The paper presents the microbiological data to assess the efficacy of enhanced removal of phosphates from domestic wastewater. Steel wire reinforced feed material has a growth-promoting effect on the flora of activated sludge and biofilm, a significant effect on the number and diversity of the protozoa species in the activated sludge and also stimulates intensive growth of Chlorella sp. and removal of phosphates. The high effect of phosphate removal is achieved due to the young activated sludge, which is in the stage of active growth. Taking into account the reinforcing effect on the rapid growth of the biocenosis of activated sludge of the loading material reinforced with steel wire, the return of activated sludge was completely excluded from the system. Studies have shown that if there is a sufficient amount of biomass attached to the reinforced loading material, we have obtained the optimal scheme for the most complete removal of phosphates with the necessary purification effect to the required standards. [ABSTRACT FROM AUTHOR] more...

Tetracalcium phosphate knows as a derivative of apatite based materials that are used in medical and pharmacy applications such as for bone and dental cement and also for drugs. The synthesis of tetracalcium phosphate requires several hours of calcining on a high-temperature furnace. In this paper, the novel fast-firing method was introduced to the synthesis process of tetracalcium phosphate to modify the solid-state reaction by the Sargin, Agris, and Moseke process to reduce energy and time for producing tetracalcium materials. One base precursor for tetracalcium phosphate was prepared by reacting calcium hydroxide and phosphoric acid with molar ratio Ca/P 2:1. The base precursors are treated with different calcination temperatures, time variation, and different quenching methods to verify which treatment will have high yield tetracalcium phosphate material. The calcination temperature range is 1200°C to 1600°C, while the calcination time varied from 3 hours to under 1 hour, also quenched by air and water. The samples were characterized by XRD to show different mineralogy yield and semi quantity measurement of tetracalcium content. Synthesized tetracalcium phosphate characterized with XRD content several apatite minerals: montetite, brushite, tricalcium, and hilgenstokite with different ratio percentages content. The semi-quantity method form XRD analysis is used to calculate the ratio. Tetracalcium phosphate yield range from 7,62% to 56,7%. The best result that yields 56,7% was treated with calcination temperature 1400°C under 1 hour and quenched with air. The results show that the fast-firing method can optimize the current solid-state reaction synthesis process, and it looks promising to develop this method to the production process. [ABSTRACT FROM AUTHOR] more...

The paper studies 5d→4f transitions in Sr9RE(PO4)7 (RE = Sc, Lu) doped with Pr3+ under X-ray and ultraviolet (UV) excitation at various temperatures and with different Pr3+ ions content. In objects with Sc, 5d → 4f emission is negligible compared to 4f → 4f emission. When Sc is substituted with Lu, 5d → 4f transition emission yield is immense under excitation in both energy ranges, while emission related to 4f → 4f transitions is weak, especially under UV excitation. X-ray luminescence yield strongly depends on temperature; the effect is stronger for objects with Lu. Luminescence decay kinetics measured for Sr9Sc(PO4)7:Pr3+ have a fast (τ∼15 ns) component. Novel Pr3+-doped phosphors may be used as a promising material for fast efficient converters of ionizing radiation. [ABSTRACT FROM AUTHOR] more...

In this paper, we present a study of the phototransference thermoluminescence (PTTL) of charges from deep traps in natural phosphate, using 254nm UV radiation. The natural material glow curve has one peak at 260°C, while the phototransferred glow curves has an additional peak at 150°C. The optimal conditions were illumination time of 180 min, and a preheating temperature of 500°C. The PTTL signal was found to be linear over the gamma (γ) dose range 0.1Gy-1000Gy. The efficiency of low dose reassessment reaches about 100 percent of the first readout. After two weeks of storage the PTTL signal was found to be 98 % of the original value. The results show the convenience of this method for the purpose of dose re-estimation over the dose range 0.1- 5Gy. Such method is useful in radiation retrospective dosimetry and dating. [ABSTRACT FROM AUTHOR] more...

Lithium cobalt oxide is commonly used as secondary battery. One of the disadvantages of lithium cobalt oxide is highly toxicity waste. One of the promising cathode is lithium iron phosphate (LiFePO4). But it has poor conductivity (10-9 S/cm), so conductive material must be added to improve its conductivity. The present paper aims to study the effect of Polyaniline (PANI) and PVDF to enhance lithium iron phosphate conductivity. PANI was prepared through interfacial polymerization. Hydrochloric acid, ammonium persulfate, and toluene were used as dopant, oxidant, and organic solvent respectively. Their morphology was confirmed by scanning electron microscopy (SEM), molecular structure was investigated by Infrared Spectroscopy, and conductivity was confirmed by four point probes method. The composite products have conductivities in the range 9.14 x 10-3 - 6.2x10-1 S/cm. This result is expected to provide an alternative conductive material that can improve the conductivity of lithium iron phosphate, as well as the alternative cathode which is environmental friendly, and no harmful waste. [ABSTRACT FROM AUTHOR] more...

The knowledge of nutrients at global or regional scales in lake is fundamental for the study of freshwater biogeochemical process. In particular, the trend for nitrate and phosphate are essential for investigating the characteristic of the lake. In this paper, the Mann-Kendall trend test is initially used to determine the evidence of monotonic trend in nutrients at two different sites of Loch Lomond, a freshwater lake in Central Scotland. Time series models which consist of parametric and nonparametric regression approaches, are then used to determine the trend. The results for nitrate show a significant smooth trend in the north basin but no evident of trend in the south basin. However, no significant trends in phosphate are exhibited at both basins. [ABSTRACT FROM AUTHOR] more...

This paper reports the development of dihydrogen phosphate ion (H2PO4-) sensor in free solution and immobilized aluminium-morin (Al-Mo) complex on poly(glycidyl methacrylate) (pGMA) microspheres. The immobilization was carried out by suspension photopolymerization technique. Based on Al-Mo solution work, phosphate can be detected from 0.1 - 15.0 ppm of dihydrogen phosphate at pH 5. Phosphate detection only takes about 5 minutes. Morphology analyses showed that the immobilization of Aluminium-Morin complex maintained the size of the microspheres and proved that entrapment involves in the formation of the microspheres. This result is further explained by Attenuated Total Reflectance (ATR) spectrum which does not show any formation of new bands. The microspheres were then used for further applications. [ABSTRACT FROM AUTHOR] more...

Single layer OLEDs by using poly(9,9-di-n-hexylfluorenyl-2,7-diyl) (PHF) as the electroluminescent (EL) layer were fabricated. This paper reports the effect of doping ratios of organic salt, tetrabutylammonium hexafluorophosphate (TBAPF6) on the turn-on voltage, brightness and the EL spectra of the OLEDs. The PHF:TBAPF6 EL layers with weight ratios of 100:x (x = 5, x = 10 and x =20) were prepared by spin coating technique using chloroform as solvent. The reduction of turn-on voltage and increment of EL intensity were achieved by increasing the TBAPF6 doping ratio. The ITO/PHF:TBAPF6(100:20)/Al device showed the best performance with turn-on voltage as low as 7 V and the highest brightness at 0.36 cd/m2. [ABSTRACT FROM AUTHOR] more...

Hydroxyapatite (HAP-Ca10(PO4)6 (OH)2), which exhibits excellent biocompatibility in the body, is one of the most widely used bioactive ceramics for biomedical applications. Along with the ability to carry the load, one of the most important properties of materials used for bone replacement is biocompatibility. In fact, HAP is a bioactive material and it can incorporate into bone structures, supporting bone in-growth without breaking down or dissolving, and it interacts with the living tissue due to the presence of free calcium and phosphate compounds. Generally, Al2O3 powder is added to HAP powder in order to obtain high fracture toughness. Al2O3 has good mechanical properties as compared with HAP, and exhibits extremely high stability with human tissues [1-6]. In this paper, the effect of microwave sintering temperature on the relative density, hardness, and phase purity of compacted bovine Hydroxyapatite (BHA) powder was reported. This research is a comprehensive attempt to develop Hydroxyapatite bio composite ceramics reinforced with alumina-Al2O3, pure titanium and pure pulverised boron powder. A Finite Element (FEM) analysis is also used for modelling to simulate the macroscopic behaviour of this material, taking into account the relevant microscopic scales. [ABSTRACT FROM AUTHOR] more...