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The increasing demand for high-performance computing necessitates efficient cooling of central processing units (CPUs) to ensure optimal functionality and prevent overheating. Nanofluids, colloidal suspensions comprising scattered nanoparticles in a base fluid, have emerged as a promising solution due to their distinct thermal properties and potential for enhanced heat transfer. Thus, the main objective of the current study is to evaluate the thermal performance and efficacy of nanofluids as coolants for desktop PC CPU cooling system. To achieve this, an extensive experimental setup was devised to analyze the heat transfer characteristics of nanofluids under diverse operating conditions. Different types of deionized water based-nanofluids, which are Al2O3, CuO and Fe2NiO4 with nanoparticle mass concentration of 0.3% were blended for 3 hours using magnetic stirrer and followed by 6 hours of ultrasonic bath at a constant temperature of 50⁰C. The stability of the prepared nanofluid will be monitored and enhanced through this method of preparation. The thermal performance of desktop PC CPU is evaluated based on the highest operating temperature of the processors under the maximum load of computer usage. For performance comparison, a conventional coolant deionized water was utilized as a reference. Among all the nanofluids used, Fe2NiO4−H2O demonstrates the most efficient cooling performance. Its temperature gradually decreases from the peak value to 45°C under the same operating conditions with other type of nanofluids used. This significant temperature reduction can be linked to the superior thermal conductivity of Fe2NiO4 nanoparticle. This finding underscores the potential of nanofluids as an advanced cooling solution for desktop PC CPU system. [ABSTRACT FROM AUTHOR]

Thanks to the unique architectural construction, nano-sized activated carbon materials demonstrate superior performance as supercapacitor electrode materials compared to conventional carbon-based materials. In this work, we demonstrated biowaste-derived tubular-like porous architecture synthesis through the KOH activation with different mass ratios (precursor/KOH) viz. 1:0.20, 1:0.25, and 1:0.30 by using a one-step pyrolysis strategy. The young coconut husk (YCH) waste was used as a carbon resource. All the synthesized samples were characterized using several techniques, including a scanning electron microscope combined with energy-dispersive X-ray, X-ray diffraction, and X-ray diffraction, to evaluate the surface topography, elemental composition, and crystalline nature of the samples. A cyclic voltammetry and galvanostatic charge/discharge technique was employed to assess their capacitive behavior. The surface morphology of YCH-0.25 shows a tubular-like porous architecture with a diameter in the range of 26-144 nm. According to CV and GCD, curves The YCH-0.25 sample attains the optimum capacitive performance as high as 231 F g−1 and 297 F g−1, respectively. This work provides a new perspective on the future management of young coconut husk waste in terms of promising clean energy technologies. [ABSTRACT FROM AUTHOR]

Silica extracted from clay of Kendari Bay has been studied. The clay was first rinsed with deionized water and dry under daily sunlight. The dried clay was then crushed and sieved of 60 meshes. Silica was obtained by leaching method using hydrochloric acid (HCl) with concentration varied from 4M to 10M with increment of 2M. During leaching process, the mixture was left for stirring at 100°C for 5 h, rinsed until neutral pH and filtered. The samples were characterized using X-ray Fluorescence (XRF) to know chemical composition of clay, X-ray Diffraction (XRD) for structural properties and Fourier Transform Infra-Red (FTIR) for functional groups. The results showed that the optimal condition for silica extraction is 6 M of 64.588%. XRD result revealed that the Bragg peak with high intensity situated at 2 = 26,6° is identified as SiO2 with Miller index of 101 of quartz type. FTIR result shown that the peak situated on 1.050 cm−1 was identified as Si-O-Si functional groups. The, we concluded that the clay of Kendari Bay was became the source of silica. [ABSTRACT FROM AUTHOR]

For the past five years, application of magnetic adsorbent for the remediation of textile effluent is receiving significant attention due to its low cost, simple preparation, and easy recovery. In this study, a magnetic bentonite composite (MBC) was synthesized through co-precipitation technique and then used for removing Methylene Blue (MB) dye. The raw bentonite and MBC were characterized using vibrating-sample magnetometry (VSM), X-ray powder diffraction (XRD), and Fourier transform infrared (FTIR) spectroscopy. The FTIR analysis indicated the possible involvement of hydrogen bonding between the iron oxide and bentonite particles to form the MBC. The magnetic composite exhibited a saturation magnetization of 9.2 emu/g with high degree of crystallinity as displayed in the XRD pattern. During a preliminary adsorption study, the MBC successfully removed 100% MB from aqueous solution with a maximum adsorption capacity of 100 mg/g. Immersion of spent MBC in various desorption eluent (1 M of NaOH, NaCl, HNO3, EDTA, and deionized water) showed a negligible MB desorption. This composite exhibits great potential as a green and efficient adsorbent for future works involving dye remediation. [ABSTRACT FROM AUTHOR]

Electrical discharge coating (EDC) is a well-known technique among researchers for modification of metallic surfaces. This process is capable of producing a hard coating layer, biocompatible and high corrosion resistance at low operating cost. Unfortunately, the process develops unfavourable microcracks and porosity on the substrate surface attributed by heat generation. Thus, in this study, the effect of several parameters to the microdefects' formation was investigated through an experimental work based on fractional factorial design. This work was conducted on a nickel-titanium (NiTi) shape memory alloy by varying the EDC parameters, namely; polarity, discharge duration, peak current, pulse interval, gap voltage and additive Ti nano powder concentration in deionized water (DI water). ANOVA results exhibited that the discharge duration has dominated the microcracks and porosity fraction on the substrate surface due to the impact of high intensity of discharge energy. Although, the Ti nano powder mixed in the DI water had capability to reduce the microcracks formation, the porosity fraction during at high gap voltage setting was elevated with the Ti nano powder mixed. [ABSTRACT FROM AUTHOR]

In the present study Si2N2O is prepared from stoichiometric mixture of Si3N4 and SiO2 through slip casting and reaction sintering method. Si3N4 and SiO2 powders were characterized for crystallographic phase and particle size distribution. The dispersion behavior of Si3N4 in deionized water (DIW) was estimated through zeta potential measurement. High zeta potential values of >45 mV at pH 10 and above indicate good dispersion. The slips of Si3N4 and SiO2 having solid loading of 69 to 72 Wt.% when slip cast into plaster molds give green density of 53±1%. On reaction sintering in the temperature range of 1550°C to 1650 ⁰C in nitrogen atmosphere the products have density of 63 to 80% and apparent porosity 12 to 33%. The samples sintered at 1650 ⁰C for 1 h and 2 h show 3-point flexural strength of about 80-100 MPa and porous microstructure. [ABSTRACT FROM AUTHOR]

The operation of pilot conversion plant in Serpong Nuclear Area to produce nuclear grade uranium dioxide from yellow cake generated liquid waste containing uranium. This uranium liquid waste remains problematic because the existing treatment processes for radioactive waste in the radioactive waste processing installation is yet to accommodate liquid waste which contained uranium. Therefore, the study for treatment of this kind of waste is necessary to support the radioactive waste management and to maintain the sustainability of the operation of the pilot conversion plant. The objective of this work is to recover uranium in the liquid waste by precipitation, thus decreasing the concentration of uranium in the liquid waste. The study was carried out by simulation using PHREEQC code and direct precipitation experiment with NaH2PO4 and NaOH as precipitating agents. The aqueous uranium in the liquid waste was precipitated with the addition of each of precipitating agent in a beaker glass to produce uranium precipitates. After the precipitation, the precipitates and the supernatant were separated by centrifugation. The uranium precipitates obtained from the experiment were washed with deionized water and ethanol. Then, a small portion of the precipitates was taken and coated with sputtered gold prior to analysis using SEM-EDS. The supernatant, meanwhile, was filtered and the concentration of uranium in the filtrate was determined using ICP-OES. The results shows that uranium precipitates with NaH2PO4 were crystalline, whereas with NaOH were amorphous. The initial concentration of uranium in the liquid waste was 2878 mg/l, whereas after the precipitation the concentration became approximately 1 mg/l. These values correspond to 99.9% aqueous removal by precipitation with those precipitating agents which indicates that this method is promising to be further developed for uranium liquid waste treatment. [ABSTRACT FROM AUTHOR]

In this paper, Aactivation of 3D printed PLA/Carbon with through electroplating at various voltages is investigated. The activated electrode was employed with water electrolysis to determine the reactivity for the hydrogen production. The objectives are to activate 3D printed PLA with nickel promoter, investigate the effect of voltage on the electrode morphology and evaluate the electrocatalytic reactivity. The electrodes were designed by using Solidwork and printed by using Fused Deposition Modelling 3D printer. Electrodeposition was conducted by using different voltages to decorate the electrodes with metallic promoters in order to activate them for the Hydrogen Evolution Reaction at the cathode. The morphology of the plated electrode electrodeposition was observed by using optical microscopy (OM) and Scanning Electron Microscope (SEM). The activated electrode reactivity was then evaluated by employing electrocatalysis, i.e., hydrogen evolution reaction. The electrode plated with Ni at 15V for 60 minutes produced the highest amount of hydrogen gas compared to other. However, further investigation by prolonging the time for 5V electroplating process showed higher hydrogen gas production compared to 15V 60 minutes electroplated electrode. Low voltage resulted in good more uniform nickel coating, while high voltage caused the coating to be peeled off as observed by scanning electron microscope & optical microscope. [ABSTRACT FROM AUTHOR]

The rapid development of motorbikes lately is marked by the many variants (types). Motorcycles are the most widely used means of transportation by Indonesian people in general. The completeness system of the machine includes the ignition system, filling system, lubrication system, cooling system, starter system and fuel system. Good engine performance is supported by several factors including fuel consumption in accordance with the working conditions of the engine, proper ignition timing, high engine compression and a strong spark to burn the entire mixture of gasoline and air at the end of the compression stroke to produce the desired combustion. to find out how the AC CDI ignition system works for the Honda Astrea Grand motorcycle and the 110 cc CDI DC Shogun ignition on CAMEL IBATE vehicles. To get a more efficient/efficient fuel flow discharge. The data analysis method to determine the fuel flow rate is by testing the Camel Ibate vehicle using the Honda Grand Standard AC CDI and the 110 cc Shogun CDI-DC at 3500 Rpm, 4000 Rpm, 4500 Rpm, 5000 Rpm, 5500 Rpm, to get the time difference required in testing the fuel flow discharge with. At 3500 rpm engine speed, the time difference between AC CDI and DC CDI is 16.22 seconds. At 4000 rpm engine speed, the time difference between AC CDI and DC CDI is 17.9 seconds. At 4500 rpm engine speed, the resulting time difference between CDI AC and CDI DC is 15.64 seconds. At 5000 rpm engine speed, the time difference between AC CDI and DC CDI is 20.97 seconds. At 5500 rpm engine speed, the time difference between AC CDI and DC CDI is 13.09 seconds. [ABSTRACT FROM AUTHOR]

The major aim of this study is to compare the power generation of carbon felt electrode and carbon paper electrode operated Microbial fuel cells (MFC) using restaurant wastewater. Restaurant wastewater samples were collected from MFC with carbon felt electrode (N=13) and carbon paper electrode (N=13) operated for 10 days (G power 80%). Voltage was measured using a multimeter and current, power, power density was calculated from it for both groups. The Power generation was found to be high in MFC operated with carbon felt electrode (410 mW/m2) due to its active surface area, strong conductivity, and good biocompatibility compared to carbon paper electrode (121 mW/m2). The independent sample T-test was done which showed that the power generation of MFC operated with carbon felt electrode (p<0.001) found to be significantly higher compared with MFC operated with carbon paper electrode. The study shows that carbon felt electrode operated MFC is able to achieve higher power generation compared to carbon paper electrode. [ABSTRACT FROM AUTHOR]

In this work, palladium metal nanoparticles (PdNPs) were prepared by pulsed ablation technique in deionized water (DIW) and a pulsed Nd-YAG laser with two wavelengths (532 nm - 1064 nm) was used and three energies were used for each wavelength (800 mJ - 900mJ -1000mJ) with a number of pulses (500 pulse) and pulse width (10 ns) and a frequency interval (6 Hz). The optical, structural and morphological properties of palladium nanoparticles (PdNPs) were studied by means of several (uv-Visible -XRD-SEM) assays. Comparison between the results based on the difference in wavelength and laser energy and the effect of the change in wavelength and energy on the properties of palladium nanoparticles (PdNPs), The resulting particles appeared in a spherical shape and tended to agglomerate and form what looked like clusters, and their size ranged between several nanometers and 30 nanometers. The particle grain size of palladium nanoparticles ranged between (17nm) at (1000mJ) at a wavelength (1064nm) and (25nm) at (800mJ) at a wavelength (532nm). [ABSTRACT FROM AUTHOR]

In this paper, Gold nanoparticles were prepared by chemical reduction method using materials Gold chloride (HAuCl4/H2O) and deionized water, This method has proven its effectiveness by obtaining gold nanoparticles with sizes (9-11) nanometers. Moreover, the resultant nanoparticles have no inclination to clump together and are distributed at the nanoscale. The process's cheap cost of execution is also encouraging. The major benefit of chemical reduction is that it is characterized by great efficiency in synthesis. [ABSTRACT FROM AUTHOR]

The article considers the electrochemical aspects of the adhesion of Micrococcus luteus 1-I on platinum, glassy carbon and carbon-paste electrodes with different surface properties. With the help of electrochemical impedance spectroscopy, equivalent circuits havebeen compiled that characterize the capacitive characteristics of the phase interfaces. A direct relationship between the capacitanceof the electric double layer and the specific surface area of the electrodes is shown. It has been shown that, on the whole, the capacitance of the electrical double layer Cdl decreases in the presence of M. luteus 1-I. Based on the data obtained, an assumption was made about the effect of cell sorption on the electrode surface area S and the thickness of the electrical double layer. The results agree well with theoretical data and are statistically significant. All of these factors may indicate the adhesion of M. luteus 1-I on the selected electrodes. [ABSTRACT FROM AUTHOR]

Indonesia is the largest nickel producers in the world in form of nickel laterite ore, its reservation about 23.67% and production about 33% of world supply chain. It is smelted as ferro nickel and nickel matte. Nickel matte, with around 77% Ni, 1% Co and 0.3% Fe, could be used as nickel source in cathode active material synthesing, NMC by using nickel sulphate route. This study dealing with synthesizes cathode active material from nickel matte. The nickel matte was converted into nickel sulfate in certain condition and catalyst and then reacting with commercials Mangan Sulphate (MnSO4) and Cobalt Sulphate (CoSO4) (technical grade) resulting NMC. The type of active material was focused on NMC 111. Then, it was dopant using lithium carbonate in varied composition, 1.35% weights to 0.4 % weights. The product of Li - NMC 111 was characterized by using AAS for ratio composition and XRD for crystallography. Based on the diffractogram, as low as LiCO3 composition will give more purity crystal and better performance in the lithium ion battery. Based on its performance, initial charging test, the lithium ion battery has working voltage in the range of 3.0 VDC and 4.2 VDC, with capacity of 0.4 mAH with stability for 30 hours of charge – discharge cycle. [ABSTRACT FROM AUTHOR]

The flexible piezoresistive sensing membrane has the tremendous opportunity in wearable and foldable devices for healthcare detection, artificial skin, human body motion, and robotics applications. The aim of this paper was to develop the polymer based piezoresistive membrane using cast solution. Poly (4-styrenesulfonic) (PSSA) were mixed with Polyvinyl alcohol (PVA) polymer by using Deionized water(DW) as a solvent, to make a series of flexible piezoresistive membranes out of PVA/PSSA and investigate their electrical characteristics across a frequency range of 20 Hz to 10 MHz. The results show that raising the concentration of PSSA from 0.2gm to 0.8gm increases the dielectric constant, conductivity, and gauge factor from 105 to 107, 10-3 s/cm to 0.1 s/cm and 2.794 to 5.092 respectively, in the proposed PVA/PSSA piezoresistive ionic membrane. The electrical properties of piezoresistive ionic membranes were analyzed using the impedance analyzer for the varying wt% of PSSA. When the wt% of PSSA was varied, it was discovered that the composition containing 0.8 gm of PSSA in PVA/PSSA based ionic membrane produces the greatest results in terms of high sensitivity and gauge factor for piezoresistive sensing applications. [ABSTRACT FROM AUTHOR]

Tea plants were discovered thousands of years ago in South-East Asia, and humankind has been drinking tea for thousands of years due to its medical benefits to prevent and treat a lot of diseases. Tea leaves are specific for their antioxidant capacities due to the presence of a wide range of flavonoid and other phenolic compounds. In this study, spectrophotometric methods were evaluated for determining the total flavonoid contents (TFCs) and ferric reducing antioxidant power (FRAP) in various green and oolong tea products collected in two specific tea-tree plantation regions in the mountainous area (Yen Bai Province-YB, the North) and Central Highland (Da Lat-DL and Lam Ha-LH, Lam Dong Province, the South) of Vietnam. The ultrasound-assisted solid-liquid extraction at 70 °C was employed to prepare the tea extracts with 70% v/v methanol in deionized water as the extraction solvent. Quercetin and trolox were used to build up the calibration curves for TFCs and FRAP, respectively. The results indicated that oolong tea products performed lower TFCs (expressed as milligrams of quercetin equivalents per gram dried weight or mg QE g−1 DW) than green tea (68.06±0.76 to 79.89±0.48 mg QE g−1 DW vs.117.4±1.7 to 244.1±3.9 mg QE g−1 DW) due to the differences in tea plant species and the oxidation levels during the fermentation period. Among the collected dried tea products, the FRAP values (expressed as micromoles of trolox equivalents per gram or µmol TE g−1 DW) were high and followed the decreasing order of YB-Green (2138±23 to 2688±40 µmol TE g−1 DW)>DL-Green (2232±60 to 2349±63 µmol TE g−1 DW)>LH-Oolong (1745.2±5.0 to 1947±45 µmol TE g−1 DW)>DL-Oolong tea products (1551±23 to 1679±25 µmol TE g−1 DW). It could be concluded that green and oolong tea products are rich sources of flavonoids and antioxidants, and the total flavonoid contents could remarkably contribute to the antioxidant capacities (r=0.841). [ABSTRACT FROM AUTHOR]

In this paper, metal oxide nanoparticles (Titanium dioxide) were prepared by using laser ablation of titanium target immersed in deionized water, where we used the technique of laser ablation in the liquid (PLAL) because of its many advantages, including being a rapid and direct way to prepare NPs and do not require long and high reaction times, Temperature and high-pressure environment and its eco-friendly method. 0ptical and structural properties of the prepared TiO2NPs studied using Q-switched Nd: YAG laser with a wavelength of 1064nm with different energies (80, 100, 120, 140, & 160) mJ /100 pulses. In addition, the prepared TiO2NPs were characterized by UV-VIS and FTIR spectroscopies. The results showed that increasing the laser energy increases an absorbance of the prepared TiO2NPs, the energy bandgap (Eg) of the prepared TiO2NPs decreased with increased Laser energy. And from the FTIR results, the formation of TiO2NPs was confirmed and it has a bond at wavenumber ranging from (400-700 cm−1) [ABSTRACT FROM AUTHOR]

Highly branched polymers such as dendrimers have the potential to be a perfect drug delivery system. Curcumin is a hydrophobic polyphenolic therapeutic drug with anti-inflammatory and antitumor effects. Due to its hydrophobic nature, its application in pharmaceuticals is hindered. Curcumin was encapsulated within the 3rd generation polyamidoamine (PAMAM) dendrimer with its NH3+ functional groups. The complex obtained had a curcumin load of 16 µg per 1 mg of dry complex and remained stable in both deionized water and methanol, showing minimal release even after 8 hours. Interactions within the complex were studied using UV-spectrophotometry and was found that the positively charged amino group of PAMAM dendrimer forms a complex with curcumin due to their ionic interactions, which was further confirmed by FTIR and NMR spectroscopy. This interaction between them enhanced curcumin's solubility in water there by improving its bioavailability. Therefore, the strategy used in this work is a suitable drug delivery system for improving many bioactive substances. [ABSTRACT FROM AUTHOR]

The objective of this research is to find out whether the method of ionization by separating water electrolysis can be used for the preparation of alkaline water production to produce hydroxyl ions which is widely talked will be useful effect for our body. This research is also useful for finding the best type of metal that is not corroded and become harmful to human health and to study the chemical reaction involved in the system. The study also included observation of the effects of the addition 100 and 200 ppm salt into system. Method used in this experiment is by separating electrolysis chamber to produce ionized water using two electrodes chamber connected by a cotton as membrane and DC adaptor as power source. Material needed for this process are separated electrolysis equipment, water, and adaptor. The result show that alkaline water will be produce by ionization of separated water electrolysis in cathode chamber while acid water will be produced in anode chamber. Research was done with variations in electrodes and composition of salt vs. contact time. Result show that most of the electrodes were corroded by salt except of aluminum. Conclusion from the experiment show that pure titanium and aluminum is suitable to prepare alkaline water using water separating water electrolysis ionization method. Key Words: oxidation, reduction, electrolysis oxidation water, electrolysis reduction water [ABSTRACT FROM AUTHOR]

One way to treat oil waste is a seawater desalination system that uses exoelectorgenic bacteria as an agent for the degradation of organic compounds contained in oil waste. Microbial Desalination Cell (MDC) is a development of Microbial Fuel Cell (MFC), a method that can eliminate salt content in seawater using electricity generated by bacteria from wastewater. Stacked Microbial Desalination Cell (SMDC) is an MDC development where SMDC uses many pairs of ion Exchange Membranes (IEMs) where IEMs are placed between the Anion Exchange Membrane (AEM) and the Cation Exchange Membrane (CEM). This is intended to increase the efficiency of electron transfer. SMDC can also return more energy than other types of MDC so that the cost is more effectively. In this research, using a 2-SMDC reactor configuration with graphite rods as anode, CFC coated with activated carbon as a cathode, potassium permanganate as catholyte, and adding ion exchange resin to salt chamber. Independent variables used in this research were activated carbon mass variations of 0, 2, and 4 g. Parameters that will be obtained are COD, electrical productivity, and pH. The results obtained in this study indicate that the optimum mass variation of activated carbon is 4 g by adding Ion Exchange resin (ratio Resin Na and Cl 1 : 1) with a COD reduction of 57.808% and produces electrical productivity of 0.000561 W/m3 , and the change in pH by 0.24. [ABSTRACT FROM AUTHOR]

Research on wastewater treatment using carbon electrode electrodegradation method has been done. This research aimed to find the optimum conditions i.e. electrolyte concentration, current, and pH in order to degrade pigment yellow 83 dyes contained in screen printing industries wastewater and to determine the quality of post-treatment water after electrolysis. Here we used the electrolysis method with a metal electrode. The research results showed that the treatment of synthetic wastewater and the screen printing wastewater was respectively 99.78 and 98.97% effective under the obtained optimum conditions i.e. at 0.5M NaCl, pH 1, and 5 Volt. Furthermore, the quality of the post-treatment water was pH 1 from 8.6 initially, COD 170.4 mg/L from 284.8 mg/L (40% declined) and TSS 2060 mg/L from 6694 mg/L (69.22%). [ABSTRACT FROM AUTHOR]

2 D materials show fascinating properties for their applications in advanced technology. Tungsten Diselenide (WSe2), a family of transition-metal dichalcogenides, has greatly inspired researchers to take up challenges in energy storage, optoelectronic and electronic applications. We have synthesized WSe2 using hydrothermal technique via the reaction of sodium tungstate and selenium power with the assistance of sodium borohydride, a reducing agent and N, N- dimethylformamide (DMF) and deionized water have been utilized as double solvent. The structural and the surface morphological properties of WSe2 have been studied using X-ray diffraction and Field Emission Scanning Electron Microscope (FESEM) which approve the high crystallinity and reveal the most thermodynamically stable Hexagonal phase of WSe2. The successful synthesis of this new class of 2D material motivated us to perform ion beam bombardment experiments for modifying its properties especially for energy applications. [ABSTRACT FROM AUTHOR]

The modern electronic devices consist of a large number of components within a reserved space. Need to enhance the data handling capacity of computational devices is continuously rising. This makes thermal management of such electronic systems more important. They require an efficient cooling system for dissipation of heat generated. Conventionally air and deionized water is used as a cooling fluid. Water based cooling systems for gaming station and high-performance computing systems is commonly available. As liquid has its own limitation in thermal transport, addition of nanosized particles in liquid enhances its capacity. Good amount of work has been reported in literature which shows that the high thermal conductivity of solid particles gives rise to enhancement in heat transfer capacity of colloidal mixture of nanoparticles and fluid. They are classified as nanofluids. In this work, experimental investigation on cooling of electronic system with heat sink mini-channel has been carried out. The working fluid used is deionized water (DI) mixed with carbon nanotube (CNT) nanoparticles. CNT is known to poses high thermal conductivity. The volume fraction of CNT in DI is varied. Constant heat flux is supplied to mini-channel from bottom using a peltier heater. Effect of various coolant's flow rates on its thermal performance is observed. Influence of various volume fraction of nanoparticles, heat fluxes has been also reported. The temperatures at inlet, outlet and four passes of mini-channel are calculated at different flow rates and power supply for both CNT-DI water nanofluid and distilled water. On increasing the Reynolds number, expected heat dissipation augmentation occurs. Furthermore, it is observed that for nanofluid the temperature difference is increased between outlet and inlet. The improvement in thermal performance utilizing nanofluid as coolant instead of distilled water was noticed. High Nusselt number is obtained as compared to distilled water. Experimental results show enhancement in heat transfer coefficient. [ABSTRACT FROM AUTHOR]

In the present work, a novel investigation on the effect of different type of polymers used as membrane substrates for application in pressure retarded osmosis was systematically conducted. Three asymmetric membranes with similar pore size but different polymers; polyethersulfone (PES), polysulfone (PSf), and polyphenylsulfone (PPSU) were used. The synthesized thin film composite (TFC) membranes were able to withstand with the applied pressure of 10 bar in pressure retarded osmosis mode when 1.0 M sodium chloride was used as draw solution and deionized water as a feed solution. Results showed that the PSf-TFC membrane gives a power density of 2.15 Wm-2, which is higher than that of the PPSU-TFC and PES-TFC membranes. It was found that the PSf-TFC is the most suitable substrate in this study with ideal porosity, good water and salt permeability, and low structural parameter which enhanced the power density. [ABSTRACT FROM AUTHOR]

Graphene oxide (GO) dispersion in different solvents has been investigated by Fourier-transform infrared spectrometer (FTIR), UV-Vis spectrometer, densimeter and Semiconductor Parameter Analyzer (SPA). GO was prepared by modified Hummers method and dispersed in different solvents, namely acetone (A-GO), ethanol (E-GO) and deionized water (DIW-GO) Full exfoliation of each dispersion was achieved by sonication. The prepared GO dispersions has been compared with raw graphite during characterization and conductivity analysis. From FTIR analysis, peak characteristics of GO can be observed at 3595 cm−1 (E-GO), 3740 cm-1 (A-GO) and 3733 cm−1 (DIW-GO) which correspond to hydroxyl group. In UV-Vis spectra analysis, two major absorbance peaks around 230 nm which correspond to л-л* transitions can be observed in all GO dispersions except for graphite. It is found that E-GO had the highest density value (2.26 g/cm3). Result obtained by SPA analysis shows that the highest resistance value (Ω) is denoted by DIW-GO (5.81x107 Ω) followed by graphite (4.86x106Ω), A-GO (4.59x106 Ω) and E-GO (3.69 x106 Ω) respectively. The results reported in this study could serve as a basis to facilitate the fabrication of GO material in various applications. [ABSTRACT FROM AUTHOR]

A dielectric barrier discharge operated at 7-9 kV (peak-to-peak value) and 28 kHz was used to produce plasma jets with helium as feed gases. For the plasma activation treatment, 20 ml of deionized (DI) water was placed in direct contact with the extruded plasma jet for the duration of 2 to 15 min. The conductivity and the acidity of DI water were found to increase with treatment time. Reactive species generated in the gaseous phase at the plasma-liquid interface were identified from the optical emission spectra and were correlated qualitatively to the changes in conductivity and acidity of the plasma-activated water. [ABSTRACT FROM AUTHOR]

In fast and accurate reserved, the method of phase HPLC was employed in the determination of the phenolic antioxidants of rosemary, for instance carnosic acids,ferulic acid,carnosol,caeffic acid, naringin,cirsimaritin and rosmarinic acid. The method reveals base line separation for Qualitative and quantitative determination for these compounds in rosemary leaves extract. The analysis can be done through the use of 0.10% phosphoric acid in deionized water in 10 min under isocratic conditions-the mobile phase was 60% acetonitrile at a flow rate of 1.5 ml/min using UV detection set at 280 nm. It is done through the use of fast liquid of chromatographic column type Hypersil 5H,C-18 (50x 4.6mmI.D),3µm particle size column. The analysis is done through the use of fresh Rosmarinus officinalis leaves methanolic extractions.Excelent linearity was taken for all standard studies to quantify the amount of antioxidant using a reproducible UV-VIS absorption method. The correlation coefficient of R value was 0.9641 and standard deviation was (SD=0.55), and the limits of the detection were less than 0.1µg/1. The results of the study confirmed that carnosic acid and rosemarinic acid were the main constituents of the rosemary, with low concentration of caeffic acid, cirsimaritin naringin, ciringin and carnosol. The UV-vis methodology can be included in the determination of other compounds and herbs parts of phenolic antioxidants. The study was also conducted to investigate the antibacterial activity of Rosmary extract on invitro growth inhibition of Eschericha coli and staphylococcus aurens by disc iffusion method, the results was showed that the extract have antibacterial activity in the growth inhibition of the tested bacteria. The HPLC analysis and UV detection were a good methods for determination and detection of active ingredients in Rosmary leaves and can be used for other plants for the same purposes and the extract have broad antibacterial activity against Gram positive and Gram negative bacteria. [ABSTRACT FROM AUTHOR]

NiS, CuS and dual phase NiS@CuS composite nanostructures were successfully synthesized via hydrothermal method. The synthesized material was subjected to structural and morphological studies using XRD and SEM. The rhombohedral and hexagonal phase of NiS and CuS was confirmed from XRD. The combination of rhombohedral NiS and hexagonal CuS together formed to produce NiS@CuS was revealed. The nanorod, agglomerated nanosheet like structures and its combination were also confirmed for NiS, CuS and NiS@CuS respectively from SEM images. FTIR spectral analysis of the prepared samples confirmed its metal sulfur vibration and also the functional groups on its surface. Predominant S(3p) with Ni(3d) emission and interstitial defects were confirmed from PL study. Further, CV measurement shows the perfect redox activity of the prepared electrodes at 10mV/s scan rate. Comparatively NiS@CuS showed very good specific area from CV curve and also the excellent water oxidation behavior from LSV as 240 mA/g at 10 mV/s. The very small Rct along with 71% retention after 12h was observed for the same nanocomposite electrode. Thus, the experimental results evidenced that NiS@CuS electrode is revealed as the excellent catalyst for electrochemical water oxidation for producing clean energy with zero CO2 emission. [ABSTRACT FROM AUTHOR]

New Inorganic-Organic hybrid crystalline material, bis (4-methyl benzyl ammonium) tetraiodo Cadmate (II) was synthesized by a slow evaporation solution growth method using deionized water as a solvent. From the single XRD characterization, the crystal structure and cell parameters were identified. EDS analysis has been carried out to confirm the elements present in the compound. The FT-IR spectrum showed that the different symmetry of vibrations of molecules in the crystal. The UV-Vis absorption measurement was carried out in the range between 200-800 nm for the grown crystal. Thermal analysis was performed to find out thermal stability of the compound and it is found to be thermally stable up to 129 °C. [ABSTRACT FROM AUTHOR]

We prepared monodispersed 3wt% photoresponsive liquid crystal 4,4'-Azoxydianisole doped in the nematic liquid crystal E7 droplets in an aqueous solution of 3wt% PVA in Deionized water by using flow focussing glass capillary microfluidic device. We studied the UV irradiation-induced Nematic to Isotropic phase transitions in hexagonally closed packed (hcp) array of droplets and in the flat geometry by measuring the transmitted intensity of a He-Ne laser from a Photodetector. The time required to go from the nematic phase to the photostimulated isotropic phase for the nematic droplets was much faster compared to the flat geometry. [ABSTRACT FROM AUTHOR]

Hydrogen is an alternative energy source that can replace fossil fuels. The latest breakthrough idea for producing hydrogen fuel is by utilizing biomass in bioelectrochemical systems, which is Microbial Electrolysis Cell (MEC). MEC is a method for producing hydrogen gas that is managed from organic materials, including from wastewater. In addition to very low energy consumption, the MEC system is able to use sludge waste as a substrate for the bacterial community to be implemented. The rate of hydrogen production with MEC is relatively lower when compared to air fermentation and electrolysis methods. Efforts that can be made to increase hydrogen production are by operating the MEC system at optimal distance between electrodes. One of the major problems that arises from the use of the MEC system is methanogens, the methane-producing bacteria. This methanogen consumes biohydrogen produced at the cathode which cause the loses of biohydrogen production in MEC system. In this research, biological control methods is utilized in bioelectrode by enriching it with denitrifier bacteria to inhibit the growth of methanogens. The MEC reactor is carried out in configuring a single-chamber MEC. Variation in denitrifier bacteria used and distance between electrodes aim to find the optimal conditions. The composition of the reactor chamber gas head is supported by using Gas Chromatography to analyze hydrogen and methane reserves. The addition of Pseudomonas stutzeri as biological control of methanogenesis could reduce the methane up to 76.28% compared to the control reactor at the first cycle. The presence of Pseudomonas stutzeri was also able to increase the H2 produced 128% higher compared to the control reactor. With the electrode spacing 0.5 cm, the H2 produced 65% was higher than the MEC reactor with 1 cm-electrode spacing. The 0.5 cm space was the optimum space for this experiment since it still supported the growth of the exoelectrogen bacteria and reduced the internal resistance within the MEC system. [ABSTRACT FROM AUTHOR]

The salt water could be desalinated by microbial desalination cell (MDC) without energy supply and simultaneously produce bioenergy. One of the factors for support their sustainability perform is a modification of electrode. Anode modifications have been proposed for salinity reduction in saline water. Immobilization of yeast cells has been applied in MDC. Yeast as biocatalyst was used as electrogenic microorganism oxidized glucose then transfer electrons generated from yeast cells to carbon electrode mediated by neutral red as redox mediator. The results were characterized by chronoamperometry and confirmed that all the anodes modified could be a promising method for long-term performance of MDC based yeast cells. [ABSTRACT FROM AUTHOR]

The Potassium Dihydrogen Orthophosphate (KDP, KH2PO4) pure single crystals and doped with Basic Violet (Crystal Violet, C25H30ClN3) dye, were successfully grown by slow evaporation method at room temperature with deionized water as a solvent to the vision of improve properties of KDP crystal. Two different concentration of Basic Violet dye 0.1mol% and 0.2mol% were considered while synthesis of KDP crystal. The Energy Dispersive X-ray Analysis (EDAX) confirms the presence of Basic Violet dye in grown crystals. A tetragonal structure of all three crystals was confirmed and the value of lattice parameter was calculated by X–Ray diffraction (XRD) analysis. UV-VIS Spectroscopy studies transparency of crystal and optical band gap is slight differ of pure and Basic Violet doped crystal. Raman Spectroscopy also studies structural mode of bond in all crystal. [ABSTRACT FROM AUTHOR]

It is reported the synthesis of CaCO3 particle by a simple and rapid procedure with different drying methods. FTIR, XRD, SEM, and PSA techniques have been used to characterize the precipitated products. Precursor for the synthesis is natrium carbonate and calcium nitrate tetrahydrate in deionized water. Reactions were conducted at a temperature of 27° C for reaction times at 60 minutes and stirring speed at 800 rpm. CaCO3 synthesized with drying using desiccator obtained a spherical and porous surface CaCO3 particle and an average diameter size of 1589.4 nm. CaCO3 synthesized with drying using freeze-drying obtained an irregular shape and average diameter size of 2669.7 nm. Different drying methods can produce different morphology dan sizes of CaCO3 on micro-scale. [ABSTRACT FROM AUTHOR]

The development of nanotechnology increased since the discovery of C60 in 1985. Due to its great potential the methods of synthesis nanomaterials are growing significantly compared with other methods i.e., laser ablation, arc discharge, etc. Arc discharge in fliud which is simple and cheap method produced high purity carbon nanoparticles with a few defect and high flexiblity. This study presents electrical properties measurement of arc discharge process using the high purity graphite (99,9% carbon) submerged in deionized water. Monitoring of current and voltage is required to understand electrodes gap and power consumption of arc discharge process. The current monitoring sensor device was made using Hall-based current sensor, while voltage value was measured directly between two electrodes in the real time. The current and voltage values were measured and analized by varying the current from the arc source i.e., 10, 20, 40, 70 and 100 A. As a results, increasing the current level and electrode gap affect in increasing power consumption of the arc discharge. [ABSTRACT FROM AUTHOR]