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In this study, the removal of dyes, sulfide, and some other components in batik wastewater using a nanofiltration (NF) membrane was investigated. Remazol red (RR dye), indigosol brown (IB dye), and sodium sulfide (Na2S) were used as models of synthetic batik wastewater. Furthermore, NF performance for treating real batik wastewater was also examined. The effects of operating conditions on flux and rejection were investigated. The results showed that all filtration had similar permeate flux behavior, where rapid flux decline was observed at the initial filtration, followed by gradual flux decrease and then reaching a stable flux. The rejections of the pollutant model during NF of synthetic wastewater were 61–76%, 90–95%, and 90–99% for sulfide, IB, and RR, respectively. The color rejection in real batik wastewater was 99.84%. Further, the removal of chemical oxygen demand (COD) reached 87.6%.&nbsp

Water is the most important thing for all aspects of life. Today, many water problems arise as a result of the decreasing amount of clean water. This is the obligation of the Central and Regional Governments to provide clean water services to the community. However, considering the wide coverage area of Indonesia and the limited government funds, it requires the support of the private sector to overcome these problems. One of them is Islamic philanthropy, especially waqf management. This study aims to determine the mechanism for utilizing cash waqf funds and the factors supporting and inhibiting the utilization of waqf funds in the clean water supply program at the Minhajus Sunnah Foundation Surabaya. This research uses a descriptive qualitative method, namely by describing the actual information that occurs in the field (field research). Data was collected by doing interview, observation, and documentation. The result of this research is the mechanism for utilizing waqf funds at the Minhajus Sunnah Surabaya Foundation, the cash waqf funds themselves obtained from their permanent donors (wakif), namely the Dar Al Ber Society Foundation which is based in Dubai, United Arab Emirates. The fund that is given according to the wishes of the Dar Al Ber Society Foundation with the terms and specifications of the project that had been determined by them. This form of utilization of waqf funds is a form of distribution by providing services directly to the community in the form of building wells.Keywords: waqf, cash waqf, utilization of waqf, water crisis

Industrial development can increase heavy metal pollution in water. Cu metal is an essential heavy metal that is needed in a certain amount by organisms, while in excess the amount is capable of causing toxic properties and environmental pollution. The presence of Cu metal in nature is considered as a pollutant in the concentration range of 0.001 ppm to 0.015 ppm. The electrochemical method can be used for detection of heavy metal. In this work, CPE was modified by electroreduction of 4-carboxyphenyl diazonium by cyclic voltammetry method by contaminating CPE into a 4-CPD solution at potential range -1.5 V to 1,0 V with 100 mV/s scan rate for 3 cycles. The modified of CPE with 4-CPD were characterized using FTIR and SEM-EDX instruments. Analysis of Cu metal using 4-CPD/CPE electrodes showed a good linearity value of 0.9909 with a low detection limit of 0.1635 ppm with the high sensitivity of 21.506 mA ppm cm-2. From these results it can be seen that 4-CPD/CPE can be used as a good Cu metal detector.

Sawdust of Oil Palm Empty Fruit Bunches (OPEFB/TKKS (Tandan Kosong Kelapa Sawit)) as a waste product from oil palm plants could be used as mesoporous carbon which was used as an adsorbent for Cu2+ and Cd2+ metal ions because it was a lignocellulose compound which had a hydroxyl (OH) functional group that could bind metals. This adsorption ability could be increased by delignification and sulfonated treatment of OPEFB (TKKS) sawdust. The treatment shown that activated OPEFB carbon can achieve maximum adsorption that is close to activated carbon.

This paper presents the design and implementation of a reduced size meander line-based 433 MHz printed dipole antenna for unmanned aerial vehicle (UAV) telemetry application. The size of the antenna is miniaturized as compact as possible to be fit and installable in the winglet of a fixed-wing UAV. To achieve a compact size, the proposed antenna is designed by involving a meander line structure. The antenna is deployed on a 1.6 mm thick flame retardant (FR) 4 epoxy dielectric substrate with the length of 232.5 mm and the width of 16.4 mm. Prior realization and measurement, the design is performed through a simulation software to obtain optimum antenna parameters including reflection coefficient (S 11 ), voltage standing wave ratio (VSWR), gain, and radiation pattern. The simulation result shows that the proposed antenna has the minimum S 11 value of -16.78 dB which corresponds to the VSWR value of 1.33, the gain of 1.79 dBi, and the operational frequency range of 414 MHz to 444 MHz. Meanwhile from the measurement result, the realized antenna has the minimum S 11 value of -9.53 dB which corresponds to the VSWR value of 2.002, the gain of 0.795 dBi, and the operational frequency range of 400 MHz to 432 MHz. Moreover, in comparison to the basic printed dipole antenna, the proposed antenna could achieve a reduction in size by 18.71%.

Up to now the Haber-Bosch process is a main choice for industry to produce ammonia from nitrogen gas. The process requires very high temperatures and pressures, and hydrogen source from fossil fuels, which produce very large CO2 gas emissions. Therefore we need other alternative process to synthesize ammonia, that can be operated at relatively low temperature and utilize environmentally friendly hydrogen source. In this study a tandem system between dyes sensitized solar cells (DSSC) and photoelectrochemical cell (PEC) has been developed. The DSSC cells were prepared using N719 dyes sensitized TiO2 photoanode. The PEC zone employed a composite of TiO2 nanotube-Bismuth Oxide Bromide (BiOBr), where the conversion of nitrogen into ammonia taken place, and its counter electrode was Ti3+-TiO2 where photocatalytic oxidation of water taken place to provide a source of protons. The DSSC zone of the developed DSSC-PEC tandem system showed solar cell efficiency up to 7.22%, while as a whole, the system provide photon to ammonia generation approximately 0.005%. The best ammonia amount that can be produced by proposed DSSC-PEC tandem system, by solely visible light energy source and water as proton, under current conditions is 4 × 10−2 µmol/hr.

The increasing circulation of unhealthy foods in various places threatens the community of malnutrition. One of which is the intake of cholesterol nutrition. When the normal limit is exceeded, it can trigger the spread of various diseases such as coronary heart disease. To anticipate the outbreak of the disease, a practical, stable, simple, and relatively inexpensive, non-enzymatic sensor device for monitoring blood cholesterol levels in some food samples such as milk and meat was developed. In this research, nickel modified catalyst on carbon paste electrodes, NiO/CPE by hydrothermal method and Ni/CPE by electrochemical method were developed. A flower-like morphology for NiO was obtained from hydrothermal method and rock-like morphology was obtained from nickel deposit. Results showed that Ni/CPE worked optimally at pH 14 with sensitivity of 0.8148 μA μM−1 cm−2 and limit of detection (LoD) of 0.1645 μM, while NiO/CPE worked optimally at pH 12 with a sensitivity of 0.1238 μA μM−1 cm−2 and LoD of 0.7804 μM. Cholesterol level measurement from the packaged milk sample showed differences of 20.42 % and 47.18 % from the nutrition table information for Ni/CPE and NiO/CPE, respectively.

Measurement of urea concentration in urine is a very important parameter for determining the state of kidney health. With this aim, a non-enzymatic urea sensor comprising Ni metal deposited on an Au electrode has been developed. Ni was first deposited on an Au electrode by varying the potential and time, and then the deposited Ni was activated in KOH to generate NiOOH, which can oxidize urea to CO2, N2 and H2 to allow it to be detected electrochemically. The results show that the Ni/Au electrode can be used to detect urea with a limit of detection (LOD) value of 3.35 × 10−2 mM, a sensitivity of 52.20 mMμA−1cm−2 and a linearity of r2 = 0.997 at a deposition potential of −0.45 V vs. Ag/AgCl after a deposition time of 180 seconds. The Ni/Au electrode has good repeatability and reproducibility (%RSD value) of 0.12% (n = 12) and shows good stability with a %RSD value of 1.60% after 9 days. The Ni/Au electrode performance is not disturbed by the presence of any interfering compounds, such as ascorbic acid, glucose, NaCl, and KCl. The Ni/Au electrode can be used to measure urea levels in urine samples, detecting concentrations of as high as 9.615 mM.

Nitric oxide (NO) plays an important role in physiological processes. NO measurement accuracy is important to understand the essential functions of NO but attaining these levels of accuracy is difficult due to NO’s short half-life. NO concentrations can be determined using an analytical method that has fast response and high sensitivity and is simple and practical. In this study, gold and platinum metals are deposited onto a screen-printed electrode (SPE) surface in a solution mixture of HAuCl4 in 0.05 M H2SO4 and K2PtCl6, in 0.05 M H2SO4, which has been modified with graphene to detect NO. Experiments that varied the deposition concentrations of the Au/Pt onto the G/SPE are conducted to obtain an optimal deposit concentration ratio between AuPt and G/SPE. NO detection tests are conducted at +0.878 V against Ag/AgCl. Deposits of AuPt/G/SPE that have 1:1 concentrations form high-performance sensors due to its high sensitivity at 23029.92 μA mM−1 cm−2, a low detection limit of 2.2 × 10−3 mM, and the best linearity, R2 = 0.9943. No is detected using the Griess Saltzman method. Based on the linearity results from the NO detection measurements, we observe that the electrochemical method provides significant improvements over the Griess Saltzman method.

Cyclic voltammetric experiments were carried out on Li+, Na +, K+, Rb+ and Cs+ in ionic liquids (ILs). Alloy formation was noted at Pt microelectrodes, but not at Ni. A range of ILs was investigated to identify the best IL to study the M/M+ redox couples, and bulk electrodeposition of all metals was observed in at least one IL, N-butyl-N-methylpyrrolidinium bis(trifluoromethylsulfonyl)imide ([C4mpyrr] [NTf2]). Mathematical simulation of the CVs in this IL was conducted as a function of temperature. The diffusion coefficients, D, of the five metal ions were determined. The formal potential, E f0 (vs. Fc/Fc+) of the five M/M+ couples was quantified, as well as the electrochemical rate constants, k 0, and transfer coefficients, α. The activation energies of diffusion, Ea,dif, of Li+ and Na+ ions, and electron transfer, Ea, of Li/Li+ and Na/Na+ were determined, and ΔS0 (vs. Fc/Fc+) estimated for the Na/Na+ couple. The trends within the group are discussed. ©The Electrochemical Society.

The electrodeposition of rubidium from an ionic liquid (IL) N-butyl-N-methylpyrrolidium bis(trifluoromethylsulfonyl)imide ([C 4mpyrr][NTf2]) has been performed and monitored at a Nickel mesh electrode by using in situ electrochemical-X-ray Photoelectron Spectroscopy (XPS) measurements. At extremely high current values during the deposition of the metal, the solvent breakdown was also observed. By choosing suitable low current values, electrodeposition of Rb can be promoted over the IL degradation. IL degradation was characterised by carbonisation of the electrode-IL-vacuum interface, with the loss of fluorine being relatively pronounced, consistent with reduction of the [NTf2]- anion. © 2011 Elsevier B.V. All rights reserved.

The real time electrodeposition of potassium has been monitored for the first time in an ionic liquid using in situ electrodeposition-X-ray photoelectron spectroscopy (XPS). The ionic liquid used was N-butyl-N- methylpyrrolidinium bis(trifluoromethylsulfonyl)imide ([C4mpyrr] [NTf2]), and electrodeposition occurred at a nickel mesh electrode. Potassium electrochemistry was monitored at the ionic liquid-vacuum-electrode interface using a novel cell design. © 2011 Elsevier B.V. All rights reserved.

Electroreduction of CO2 was studied at copper-modified boron-doped diamond (Cu-BDD) electrodes as the working electrode. The Cu-BDD electrodes were prepared by electrochemical reduction with various concentrations of CuSO4 solutions. FE-SEM was utilized to characterize the electrodes. At Cu-BDD electrodes, a reduction peak at around -1.2 V (vs Ag/AgCl) attributtable to CO2 reductions could be observed by cyclic voltammetry technique of CO2 bubbled in water containing 0.1M NaCl. Accordingly, electroreduction of CO2 was conducted at -1.2 V (vs Ag/AgCl) using amperometry technique. The chemical products of the electroreduction analyzed by using HPLC showed the formation of formaldehyde, formic acid, and acetic acid at Cu-BDD electrodes.

The development of non-enzymatic glucose sensor has much attention due to their applications in glucose monitoring. In this research, copper oxide is used as a non-enzymatic glucose sensor by oxidizing glucose to gluconolactone. Copper was electrodeposited on Carbon paste electrode (CPE) at constant potential. The experimental condition was varied in electrodeposition of Cu with the following parameters: Electrodeposition time 60 s, 120 s and 180 s and potential reduction -0.166 V, -0.266 V and -0.366 V. The effective performance of these working electrodes in sensing glucose was investigated. The Cu/CPE which used -0.366 V potential reduction and 120 s electrodeposition time shows the best performance. The amperometric response current in concentration range 1.6-62.5 mM of glucose gives the good linearity R2 = 0.9988, low detection limit 0.6728 mM and high sensitivity 1183.59 µA mM−1cm−2. Furthermore this sensor exhibited a good repeatability with %RSD = 1.31% (n=10) and high stability with %RSD = 1.51% ...

In this era decentralization, there has been an increasing transfer authority from central government to local government. As a result, some aspects of tourism management have been transferred to local level. This study uses the authority of the Berau local government to illustrate this. Using a descriptive case study with focuses on 7 sub-districts in the Berau Regency, the data were taken by personal observations made through visits and in depth interviews with the regent, head of culture and tourism office and 7 chiefs as the key informants. It was found that the Berau local government give limited authority to the sub-district offices to manage tourism in local areas, however, they do not provide adequate funding for tourism development. They are required to coordinate with the Culture and Tourism Office (CTO) in the Berau Regency. This leads to delays in the development of tourism. This can be seen in public facilities which are not properly maintained, and potential tourist attractions which are not recognized as such, and have not been taken over and maintained by the government. It is suggested that the Berau Local government should transfer authority to the sub-district offices for the sake of efficiency since they posses greater understanding of their areas of responsibility.

Cyclic voltammetry experiments were conducted using solutions of Na + ions in 12 different ionic liquids (RTILs) on a nickel microelectrode in order to observe the deposition and stripping of metallic sodium. In most of the liquids the potential window was insufficient to observe the formation and removal of bulk sodium, despite the enlargement of some potential windows in the presence of sodium. However, in the ionic liquids N-butyl-N-methylpyrrolidinium bis(trifluoromethylsulfonyl)imide ([C 4mpyrr][NTf2]), N-ethyldimethylpropylammonium bis(trifluoromethylsulfonyl)imide ([N2,1,1,3][NTf2]) and N-hexyltriethylammonium bis(trifluoromethylsulfonyl) imide ([N 6,2,2,2][NTf2]) the deposition and stripping peaks for the bulk sodium were observed, allowing simulation of the current-voltage curves and extraction of kinetic and thermodynamic data, notably the electrochemical rate constant, k0, and the formal potential, Ef0, for the Na/Na+ couple. Variable temperature measurements also gave quantitative information on the temperature dependence of Ef0, dEf0/dT. Diffusion coefficients for Na+ ions in the three RTILs are also reported. All parameters are compared and contrasted with that of the Li/Li+ couple, demonstrating that sodium possesses a more positive Ef0 than lithium in the investigated RTILs, although the difference is markedly less than that in solvents such as water or ammonia. © 2010 American Chemical Society.

Azelaic acid is one of the substances that has anti-acne and skin lightening effects which is often added to cosmetics. In the acne treatment, the azelaic acid is generally used with a concentration of 20% in cream formulation and 15% in gel. The use at concentrations below 10% is not recommended because it does not work effectively. While the use of above 10% is categorized as a medical treatment. In Indonesia, the Head of the National Agency of Drug and Food Control (BPOM) has issued Regulation No. 18 of 2015 on the Technical Requirements of Cosmetics Ingredients Annex V stating that the azelaic acid is banned in cosmetics. However, until this research began the BPOM has not had a valid method to identify it in cosmetics. Consequently, surveillance of such ingredient in products is hard to do. In this research, the fatty acid standard analysis method of AOAC International was modified and validated to be used in the laboratory. The method of analysis involves heating the cream preparations dissolved with methanol and then added BF3-methanol catalyst, followed by extraction and analysis using GCMS. The validation of method shows that the calibration curve is linear with correlative value of 0.9997. The method is fairly sensitive with 0.02% detection limit, and fairly precision with relative standard deviation (RSD) of between 0.626-0.961% and fairly accurate which the recovery percentage is 99.85% at range 98.27-100.72%. In sum the results demonstrate that the method can be used as a routine analysis method for laboratory testing.

The Li/Li+ couple is investigated in the room temperature ionic liquid N-butyl-N-methylpyrrolidinium bis(trifluoromethylsulfonyl)imide, [C4mpyrr][NTf2], at a range of temperatures varying from 298 to 318 K. Experiments are conducted using both nickel and platinum microelectrodes. On nickel, a single stripping peak is observed for the stripping of bulk lithium that allowed thermodynamic and kinetic parameters to be extracted via computational simulation. At 298 K, the electrochemical rate constant (k0) = 1.2 × 10−5 cm s−1, the diffusion coefficient (D) = 4.5 × 10−8 cm2 s−1, the formal potential (Ef0) = −3.26 V versus the Fc/Fc+ reference couple, and the transfer coefficient (α) = 0.63. On platinum, multiple stripping peaks are observed due to the stripping of Li−Pt alloys in addition to the stripping of bulk lithium. The ratio of the different stripping peaks is found to change with temperature, indicating that Li−Pt alloys are more thermodynamically stable than pure bulk lithium and platinum.

Interaction between TiO2 and dyes sensitizer have been studied. The chlorophyll presents in the crude leave extract (CLE-dye) from cassava (Manihot utilissima) was immobilized on to the photo-anode, consists of TiO2 supported by fluor doped Tin oxide (SnO2-F) Glass. The TiO2 was prepared by Rapid Breakdown Anodization (RBA) method then immobilized on to glass coated by SnO2-F using doctor blade technique, to give CLE-dye/TiO2/SnO2-F/Glass photo-anode. The prepared photo-anode was characterized by UV-Vis-DRS, FTIR, XRD, SEM, electrochemical and spectro-electrochemical systems. In this study, the HOMO (highest occupied molecular orbital) and LUMO (lowest unoccupied molecular orbital) energy level of the CLE-dye were empirically determined by cyclic voltammetry method, while spectro-electro-chemistry method was used to determine the coefficient of degradation and formation of the dyes, and diffusion coefficient of the hole recombination as well. Good anchoring between TiO2 with dye extracts (CLE-dye) can be seen from value of dye LUMO energy level (-4.26 eV), which is approaching the conduction band of TiO2 (-4.3 eV). The coefficient of degradation and formation of the CLE-dye showed a quasi reversible and diffusion coefficient hole recombination values were small, indicated that it is quite suitable as a sensitizer in a dyes sensitized solar cell.

Lembar Pengesahan tidak disertai tanda tangan dosen pembimbing “The Elements of Nature” merupakan sebuah komposisi musik programatik untuk orkestra yang menggambarkan keempat elemen alam, yaitu: air, udara (angin), api, dan tanah. Berdasarkan latar belakang masalah yaitu langkanya komposisi programatik yang menggambarkan keempat elemen alam serta rendahnya kesadaran manusia terhadap tugas dan tanggung-jawabnya untuk memelihara kelestarian alam, maka penelitian ini bertujuan untuk menghasilkan sebuah komposisi programatik yang dapat menggambarkan karakteristik keempat elemen alam serta mengingatkan akan tugas dan tanggungjawab setiap umat manusia. Hasil akhir dari penelitian ini adalah dalam bentuk sebuah komposisi programatik untuk orkestra berjudul: “The Elements of nature” yang terdiri dari empat movement, yaitu: 1) First Movement: Water, 2) Second Movement: Air, 3) Third Movement: Fire, 4) Fourth Movement: Earth.

Cyclic voltammetry experiments are carried out using a 0.1 M Li+ solution in 12 different room temperature ionic liquids (RTILs), [C 4mpyrr][NTf2], [C4dmim][NTf2], [N2,1,1,3][NTf2], [N6,2,2,2][NTf2], [C4mim][OTf], [C4mpyrr][N(CN)2], [C 2mim][NTf2], [P14,6,6,6][FAP], [C 4py][NTf2], [C4mim][PF6], [C 4mim][NTf2], and [N1,8,8,8][OTf], on a Ni microelectrode to investigate the deposition and stripping of lithium from the electrode surface. [C4mpyrr][N(CN)2], [C 2mim][NTf2], [P14,6,6,6][FAP], [C 4py][NTf2], [C4mim][PF6], [C 4mim][NTf2], and [N1,8,8,8][OTf] did not have a wide enough potential window to observe the deposition and stripping of bulk lithium. In the experimental data recorded for [C4mpyrr][NTf 2], [C4dmim][NTf2], [N2,1,1,3] [NTf2], [N6,2,2,2][NTf2], and [C 4mim][OTf], a single stripping peak for bulk lithium is seen, and kinetic data for the Li/Li+ couple are extracted by comparison with computational simulations. The electrochemical rate constant, k0, is found to have values ranging from (1.3 · 10-6 to 1.2 · 10-5) cm· s-1. Diffusion coefficients for the Li+ ion in these five RTILs are also reported. © 2010 American Chemical Society.

The Li/Li+ couple is investigated in the room temperature ionic liquid N-butyl-N-methylpyrrolidinium bis(trifluoromethylsulfonyl)imide, [C4mpyrr][NTf2], at a range of temperatures varying from 298 to 318 K.Experiments are conducted using both nickel and platinum microelectrodes. On nickel, a single stripping peak is observed for the stripping of bulk lithium that allowed thermodynamic and kinetic parameters to be extracted via computational simulation. At 298 K, the electrochemical rate constant (k0) ) 1.2 X 10-5 cms-1, the diffusion coefficient (D) ) 4.5 X 10-8 cm2 s-1, the formal potential (E(f)0 ) -3.26 V versus the Fc/Fc+ reference couple, and the transfer coefficient (alpha) = 0.63. On platinum, multiple stripping peaks are observed due to the stripping of Li-Pt alloys in addition to the stripping of bulk lithium. The ratio of the different stripping peaks is found to change with temperature, indicating that Li-Pt alloys are more thermodynamically stable than pure bulk lithium and platinum.

The remarkable electrocatalytic properties and small size of carbon nanotubes make them ideal for achieving direct electron transfer to proteins, important in understanding their redox properties and in the development of biosensors. Here, we report shortened SWNTs can be aligned normal to an electrode by self-assembly and act as molecular wires to allow electrical communication between the underlying electrode and redox proteins covalently attached to the ends of the SWNTs, in this case, microperoxidase MP-11. The efficiency of the electron transfer through the SWNTs is demonstrated by electrodes modified with tubes cut to different lengths having the same electron-transfer rate constant.