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This study aimed to synthesize nanosized Mg0.2Fe2.8O4/AC/TiO2 composite for removal Pb(II) from water. The crystal structure and functional group of the sample were evaluated using XRD and FTIR spectroscopy. The morphology and band gap energy of the sample were characterized by means of SEM and UV-Vis spectroscopy. Meanwhile, the absorbance performance of the composite for removal Pb(II) was evaluated using AAS characterization. The results of the data analysis in this study showed that the Mg0.2Fe2.8O4/AC/TiO2 composite was successfully synthesized using coprecipitation method. The result of the XRD characterization presented the two phases for Mg0.2Fe2.8O4 and TiO2. The FTIR characterization results showed that the composite had a Fe-O bond at the tetrahedral and octahedral positions that were detected in the wavenumber range of 800–500 cm−1. The SEM image showed that the morphology of composite tended to agglomerate with a particle size distribution of 44.3 nm. The band gap energy resulting from the UV-Vis data analysis was 3.492 eV. Interestingly, the absorption efficiency for removal Pb(II) of the Mg0.2Fe2.8O4/AC/TiO2 composite reached 99.08%–99.90%. [ABSTRACT FROM AUTHOR]

The aim of this study was to fabricate an HAp/Zn-ferrite nanocomposite for drug delivery application. The HAp/Zn-ferrite nanocomposite was synthesized using the coprecipitation method. The nanocomposite obtained was then characterized using XRD, SEM, and FTIR. Meanwhile, the drug delivery performance of the synthesized nanocomposite was characterized with UV-Vis to determine the loading and releasing capabilities. The result of XRD data analysis showed that the HAp phase had a crystallite size of 10.0 nm with a hexagonal crystal system. The presence of a Zn-ferrite was detected with a cubic spinel system with a crystallite size of 13.4 nm. The results of the FTIR analysis showed that the presence of the HAp phase was indicated by the presence of PO43-, CO32- and O-H groups. Meanwhile, the Zn-ferrite phase was indicated by Fe-O and Zn-O vibrations. The surfactant element was detected by the vibrations of CH2, COO−, C-C, and O-H groups. Based on the SEM image, it was known that the aggregated particle size was 60 nm with spherical morphology in the form of granular. The result of the UV-Vis data analysis showed that the nanocomposite had the ability to load doxorubicin with a capacity of 27.61 mg/g and the ability to release doxorubicin, which was relatively stable, reaching 79.15% in 300 minutes. [ABSTRACT FROM AUTHOR]

TiO2/SWCNT nanocomposite has been successfully synthesized by the sol-gel method. Single-walled carbon nanotubes (SWCNT) functionalized with acid. TiO2/SWCNT composite was coated on the cork with a dip-coating technique. The crystal structure, morphology, and physicochemical properties of the composites were characterized by FTIR, XRD, SEM-EDX, SEM mapping, and UV-Vis spectra. FTIR data obtained functional groups of TiO2 and carbon. XRD test shows the crystal structure and shape of the nanoparticle material. SEM test was found that TiO2 was firmly attached to the sidewall of the SWCNT. The performance test of TiO2/SWCNT composite was evaluated by monitoring the degradation rate of methylene blue (MB) under a solar simulator. There was a significant decrease in the concentration of methylene blue (MB) when TiO2/SWCNT composite coated on the cork was added. After degradation for 2 hours, the results of the effectiveness of TiO2/SWCNT composite are approximately 99%. The photocatalytic activity of the TiO2/SWCNT nanocomposite in this experiment was influenced by the different compositions of TiO2 and SWCNT, the method used, the success of coating on the cork and light from the solar simulator. [ABSTRACT FROM AUTHOR]

Nowadays there's a high demand for Electrochemical Energy Storage which has the high specific capacitance, power density, and energy density. To address this need, supercappteries are being developed that can combine the merits of batteries and supercapacitor into one device as innovative hybrid EES devices. Herein, Mn2O3/GO/AC composite has been synthesized by using a simple procedure for blending and subsequent annealing procedure. This composite was applied as anode material in supercapatteries. With the mass variation Mn2O3 and the scan rate variation, it shown that 20 wt% Mn2O3 at 10 mV/s has the highest spesific capacitance among them, 18.93 F/g, and 2.63 Wh/kg for energy density. [ABSTRACT FROM AUTHOR]

In this research, we produced Co0.6Fe2.4O4 nanoparticles covered by natural surfactants from Syzygium polyanthum extract. The results of XRD analysis showed that the Co0.6Fe2.4O4 nanoparticles were successfully synthesized, which was indicated by the presence of the spinel phase without other phases. The Co0.6Fe2.4O4 nanoparticles had a particle size of 12.1 nm. SEM image indicated that the morphology of the nanoparticles was spherical and agglomerated with an average particle size value of 34.2 nm. Furthermore, the FTIR spectrum showed the vibrational peaks of C=C and C-H at the wavenumbers of 1633 cm−1 and 2881 cm−1, indicating the presence of the surfactant Syzygium polyanthum. At the wavenumbers of 500₋600 cm−1, the vibrational peaks of Fe-O and Co-O were overlapped, which indicated that the Co2+ ion has succeeded in replacing the position of the Fe3+ ion. Our data analysis results also captured that the Co0.6Fe2.4O4 nanoparticles using natural surfactants from Syzygium polyanthum are potential candidates as high-performance antifungal agents. [ABSTRACT FROM AUTHOR]

The development of a new generation of SWCNT/Si heterojunction solar cells has attracted great interest in research due to the extraordinary optoelectronic properties of single-walled carbon nanotube (SWCNT) materials. On the other hand, SWCNT has a weakness; namely, it is hydrophobic, so it is necessary to add hydrophilic functional groups to its surface so that it can be dispersed in organic solvents. In this study, we investigated the effect of functionalization treatment on SWCNT surfaces on solar cells performance. SWCNT is functioned by wet method using H2SO4 and HNO3 to form carboxylate groups along the SWCNT sidewalls. Characterization of samples using XRD to determine the F-SWCNT crystal phase and structure, SEM to characterized the morphology of the sample, FTIR to determine the functional group of the sample, and solar simulators to determine the efficiency of solar cells. Based on the solar simulator testing results, the power conversion efficiency increased significantly from 2.59% to 6.29% after functionalization treatment. [ABSTRACT FROM AUTHOR]

The evolution of energy storage devices that have specific capacitance, high power density, and high energy density is an important for human life. Supercapacitor is a complimentary of replacement a battery that has been extensively developed. The supercapacitor shows the high capacity and power density. The disadvantage of energy density of supercapacitor may be overcome by combining with the advantage of battery in supercapattery. Supercapattery is an ideal type of energy storage because it has a good energy density of batteries and a greater power density of supercapacitors. Cobalt and Zinc are transition metal electrodes that have been widely studied as supercapacitor electrode materials because they have high conductivity and electrochemical activity. Here, Mn2O3 material has high redox and is non-toxic, so it has the potential to be used as electrode material in supercapattery. Initially, the two materials were synthesized into a composite paste which was then deposited on the substrate using the doctor blade method. Furthermore, the electrode M/Mn2O3 (M=Zn, Co) was arranged with a separator and the 1 M Na2SO4 electrolyte to forms a supercapattery. In this work, we have the specific capacitance of 46.95 F·g−1 for supercapattery (Zn/AC/Mn2O3//AC) and 21.83 F·g-1 for (Co/AC/Mn2O3//AC). [ABSTRACT FROM AUTHOR]

Photo-anodes based on TiO2 have been widely used in DSSC devices. However, TiO2 has a high rate of electron recombination, thus limiting the energy conversion of the DSSC. One of the strategies to increase TiO2 capability is to perform surface functionalization with other materials such as carbon. Carbon has a large specific surface area, high electron mobility, excellent optoelectronic and electrocatalytic properties. Activated Carbon (AC) is an allotrope of carbon with the highest surface area, while Black Carbon (BC) has better electrical conductivity. Surface area and electrical conductivity are important parameters to produce high-efficiency DSSC. In this research, the effect of TiO2/C (C=AC and BC) nanocomposites as a photo-anode for DSSC have been investigated. The TiO2/C photo-anode was fabricated by a doctor blade method. It is found that TiO2/C nanocomposite improves efficiency DSSC based on TiO2. The optimum performance was obtained on TiO2/AC photo-anode with an efficiency of 0.475%. [ABSTRACT FROM AUTHOR]

Although the application of thermoelectric in the various field has been implemented, the effort to search new materials remain actively conducted. Thermoelectric devices may help human life not only in harvesting renewable energy, but also reduce heat pollution. As a tropical country, Indonesia produces a lot of unused heats energy from various machines, households, or natural phenomena. The research to produce new materials, as well as their thermoelectric devices, are essential. Following our previous work, the CuS based materials may need to be improved the phase fraction, crystallite size, and crystallinity. The role of modifying ion fraction in the Cu site is expected to modify its local structure. A small different in ionic radii as well its valence may enrich the local distortion as well as their anisotropic heats and electrical conductivities. Shortly, the CuSNi was syntheized using modification of polyol method. The first step was dissolving raw materials using Tetraethylene glycol (TEG). All the process were kept in oxygene free condition. For the reason, we used a system which allowing a flowing nitrogen gas at a temperature of 150 °C and followed by centrifugation of the solution. The black powder was obtained after drying process using a vacuum desiccator. The black powder of CuSNi nanomaterials were characterized XRD, electrical conductivity and FTIR. [ABSTRACT FROM AUTHOR]

One of the hot materials in thermoelectric is the skutterudite CoSb3 compound, which shows excellent potential as a thermoelectric material because Sb-based skutterudite thermoelectric materials have high mobility, large atomic mass, and high electrical conductivity. The effort of substituting transition metal (Fe) or (Ni) ions at Co site is an attempt to modify the local distortion and increasing electrical conductivity. In this work, we report the synthesis of the skutterudite CoSb3 compound using a modified polyol method. We used CoCl2.6H2O, FeCl3.6H2O, NiCl2, and SbCl3 raw materials as precursors. During the process, we used polyvinylpyrrolidone (PVP) as a stabilizer. The precursors were reduced by NaBH4 in tetraethylene glycol (TEG) at 513 K in a nitrogen atmosphere with 30 minutes for holding times. The yielded products were characterized by XRD, SEM-EDX, FTIR, and electrical conductivity. From the analysis of XRD data, we found that the nanoparticles show grain size between 15 to 32 nm. The nanoparticles were mostly identified as the CoSb3 phase, and the other phase of CoSb2 was also detected. And then, from the analysis of SEM-EDX data, there was agglomeration in the samples so that the particles size become larger and unstable. The chemical bonds of samples actually in the wavenumber range below 500 cm-1. The electrical conductivity increased with increasing stoichiometry fractions of Co1-xFexSb3 (x = 0, 0.05, and 0.1) or Co1-xNixSb3 (x = 0, 0.15, and 0.2) indicating that the samples can be used as a raw material for the thermoelectric device. The values of electrical conductivity for samples lay between 103 to 104 Ω-1cm-1, which also indicates the samples were semiconductors. [ABSTRACT FROM AUTHOR]

Green energy production for environmental protection and its sustainability has been a hot topic for the last decade. The solar source is one of the candidates for green energy to be developed in Indonesia. It is because of the tropical climate that makes Indonesia receives a lot of sun exposure. Besides, the development of green energy needs to be balanced with the development of better energy storage. The high-power density, long lifetime, and environmentally friendly are exciting and unique points of a supercapacitor. Research of photo-supercapacitor, which integrating solar cells with a supercapacitor, has been developed widely. This Integrated structure will capture and convert light energy into electrical energy then store it. Investigation on improving DSSC performance was carried out in many ways, such as a variation on dye materials, variation on the photoanode material, and other component variation, observations on the effects of temperature variations in the growth of photoanode materials, and investigation on the role of blocking layers and any others. To obtain a good start for the next investigation, we need a complete map of the recent progress on the integrated photo-supercapacitors, mainly the device constructed from EDLC and DSSC. This review article is focused on summarizes current trends in the structure and performance of integrated EDLC Supercapacitor with DSSC. The optimized additional blocking layer in the DSSC section for integrated photo-supercapacitors devices is also proposed. [ABSTRACT FROM AUTHOR]

Supercapacitor is able to provide fast charging rate, environmentally friendly and relatively abundant material availability. Manganese dioxide (MnO2) has a high potential to use as a supercapacitor electrode material because of its significant advantages compared to other metal oxides such as high specific capacitance due to the reversible redox reaction and affordable prices. Briefly, the experiment begins with the preparation of a composite solution with a variety of compositions that was deposited on the aluminum foil substrate as electrodes using the doctor blade method. The supercapacitor was packed in a coin cell with 1 M Et4NBF4. The symmetric supercapacitor cycled in the cell potential window of 0-2 V, exhibited excellent specific capacitance of 52.87 F g−1, with power density of 344.94 Wh kg−1 and maximum energy density of 21.84 Wh kg−1 with 82.23 % capacity retention for 100 cycles. [ABSTRACT FROM AUTHOR]

Supercapacitor has received considerable attention as a promising energy storage device due to its fast charging, excellent cyclic stability, and high-power density. Activated carbon is the main material used to make supercapacitor electrodes because it has a high theory-specific surface area reach of 2,685 m2g−1 and low cost. However, structure micropore activated carbon had poor ionic diffusion and transportability that make inefficient surface area utilization, long charge-discharge performance, and low cycle life. Therefore, continuous research is needed to improve supercapacitor performance by adding and modifying structure micropores to increase the performance of electrochemically active sites so that ionic diffusion is better. This research is focused on the influence of concentration PVP immersion 0 M and 0.06 M with the dehydrogenation method. The higher concentration PVP strongly influenced the microstructure, morphology, and electrochemical process. The activated carbon mesoporous was characterized by XRD, SEM – EDX, FTIR, BET, and Charge Discharge. Further, the supercapacitor with the best performance is shown by the highest concentration of PVP 0.06 M exhibited the highest specific capacitance, energy density, and power density of 83.83 F.g−1, 60.06 Wh kg−1, 454.24 Wkg−1. ACM-0.06 had highest cycle stability in the cell voltage of 0-2.4 V at a current density of 0.1 Ag−1, and maximum energy density is 58.96 Wh kg−1 with 95.82 % capacity retention after 25 cycles. [ABSTRACT FROM AUTHOR]

The development of thermoelectric device engineering has begun with the exploration and innovation of the use of new materials, defect engineering, doping engineering, and material mixing experiments. In previous studies, modifications have been made to the GO/rGO thermoelectric by doping with atom S but in previous studies have not conducted research on other atomic doping and the influence of doping concentrations. In this study, graphene oxide-based thermoelectric devices were doped by phosphorus and nitrogen atoms and modifications to the width of rxGO in the xGO /rxGO pair to get different areas. xGO materials were synthesized with added ultrasonic wave technique from graphene oxide material, then deposition to polyimide substrates. The fabrication process was done to form PGO/rPGO line modification of 0.5/0.25, 0.5/0.5, 0.5/0.75 mm and NGO/rNGO line modification of 0.75/0.75, 0.75/1.00 mm for using irradiation laser technique with length wave 405 nm and power 1.5 W. The characterizations used are X-Ray Diffraction, SEM, Temperature sensor and I-V. The voltage comparisons result of modification rPGO width line dT=10K were rPGO line width 0.25 mm>0.5 mm>0.75 mm (0.201, 0.165, and 0.126 Volts) Volt, as well as the seebeck coefficients comparison result were rPGO line width 0.25 mm>0.5 mm >0.75 mm (3.33, 2.95, 2.18) x 10−4 V/K. The voltage comparisons result of modification rPGO width line dT=10K were rNGO line width 0.75 mm>1.0 mm (0.47 and 0.4) Volt, as well as the seebeck coefficients comparison result were rNGO line width 0.75 mm>1.0 mm (2.52, 2.47)×10−2 V/K. [ABSTRACT FROM AUTHOR]

Energy storage continues to be a growing research topic. Supercapacitors are a good new choice of energy storage devices because they have good performance with high-density values, relatively fast charging, long-lasting lifetime, and are included in environmentally friendly technologies. The development of materials and structures in an extensive manner continues to be studied. Materials that can support energy storage devices have high capacitance, such as Activated Carbon (AC) and Bismuth Phosphate (BiPO4) as electrode materials. However, the energy density of carbon-based supercapacitors is still low. On the other hand, BiPO4 has good crystallinity and stability, high thermal and chemical properties, and has an ideal redox-active specificity as a supercapacitor electrode material. There is a lot of research on supercapacitor materials that have been released. The article summarizes current trends in the development of supercapacitor material synthesis and supercapacitor performance, particularly AC-BiPO4−based electrodes. The use of BiPO4 phosphate metal materials optimized to improve the performance of the supercapacitor electrode material is also proposed. Several supercapacitor material applications and new developments of supercapacitors and prospect analysis are also presented in this report. [ABSTRACT FROM AUTHOR]

A fuel cell is well known as clean energy that can be categorized as a renewable energy source. Proton Exchange Membrane Fuel Cell (PEMFC) is one kind of fuel cell, which works in low temperatures using a simple structure. Regarding this advantage, PEMFC can be a chance for introducing fuel cell process to students in vocational high school with renewable energy majors. Reaching the goal requires a learning media that can show the structure and process using interactive educational kits. The educational kits are built as trainers, which could be more effective when integrated with smartphone applications. The application can work with multi-platform interactive media, such as augmented reality. Then, the educational kits named Robo-PEM were developed to introduce PEMFC implementation by using Science, Technology, Engineering, and Mathematics (STEM) model. The Robo-PEM consists of a trainer, job sheets, and material course, which are combined in the Robo-PEM application. The Robo-PEM educational kits were evaluated by learning media experts. The result shows that the Robo-PEM educational kits were valid and could be implemented for learning media in vocational high school. [ABSTRACT FROM AUTHOR]

Dye Sensitized, Solar Cell (DSSC) is the most attractive technology in third-generation solar cells due to its simple operation, easy fabrication, great use of raw materials, and ability to be flexible panels. One of the materials that are often used in DSSC is titanium dioxide. Titanium dioxide is a semiconductor material formed from Ti4+ ions and O2- ions. Titania has a stable chemical structure under ultraviolet light. The anatase phase of titania has high photocatalytic activity compared to other phases, so it is widely used for DSSC applications. One of the important components in DSSC is the stability and morphology of the photoanode, so that in this study additional treatment will be carried out on the TiO2 photoanode. The addition of this treatment aims to improve the interconnection of TiO2. One of the materials used as a treatment is TTIP. This treatment is carried out by dip coating. From the experiments, the data shows that the efficiency increased up to 30% after treatment, from 3.78% to 5.45%. This study can explain through the morphology of the SEM characterization results where it is seen that there is a TiO2 layer with a decrease in porosity from 64% to 60% after treatment. In addition, this treatment also shows an increase in the effectiveness of TiO2 charge transfer as indicated by the results of impedance analysis where the RCT of the sample without treatment is 15 ohms and the sample with treatment is 8 ohms. [ABSTRACT FROM AUTHOR]

One-dimensional (1D) nanostructures are known to contribute a straight pathway for electron transfer to achieve good device performance. Besides that, Titanium dioxide (TiO2) is a metal oxide semiconductor, investigated as a material with upstanding physical and chemical properties with excellent light sensitivity, good relialibility in the environment, and low synthesis costs. In this research, the composite of ZnO nanorod/TiO2 designed to become a semiconductor coating material for photoanodes to support the process of electron transport. In this research, hexagonal structures of ZnO nanorods were synthesized by various growth time of hydrothermal synthesis method. The growth time affects to ZnO nanorods was systematically investigated on ZnO nanorods/TiO2 composites by scanning electron microscopy. From the XRD analysis showed that the ZnO nanorods in a crystalline phase in ZnO nanorods/TiO2 composites. Its crystallinity increases with increasing hydrothermal duration. In addition, the hydrothermal duration of 5 hours resulted the largest diameter and thickness of ZnO nanorod. [ABSTRACT FROM AUTHOR]

The design innovation and composition of TiO2 as a photoanode have been continuously studied in recent years to improve the photoconversion performance of Dye-sensitized Solar Cells (DSSC). The important components in the formation of TiO2 paste are solid content, solvents, and organic compounds as binders. In terms of solvents, water or simple alcohol are not suitable for screen printing methods, because cracking will occur after the annealing process by rapid evaporation. In this report, we investigated the addition of nitric acid (HNO3) and ethyl cellulose (CH2CH3) as a binder for optimize the overall DSSC performance. TiO2 photoanode was synthesized by screen printing method through the initial stage of making blocking layer with spin coating method. The effect of nitric acid and ethyl cellulose on, TiO2 powder was studied intensively to determine the best photoconversion performance. TiO2 films were prepared by varying the process without and with post-treatment. The XRD pattern confirmed the presence of a pure anatase phase of TiO2. The morphology of the photoanodes surface area were studied through SEM characterization. The characteristics of J-V shows an increasing in photocurrent and efficiency through the post-treatment process. DSSCs based on TiO2-HNO3 photoanode with post-treatment exhibited a highest efficiency of 3.59%. We found that the sample with post-treatment process have a smaller impedance than sample without post-treatment with charge transfer resistance (RCT) of 10 Ω and 23 Ω, respectively. It may indicate that the TiO2 film with post-treatment have a better interconnection then charge transfer and charge extraction process are more effective and resulting higher efficiency. [ABSTRACT FROM AUTHOR]

Rheumatic heart disease (RHD) is recognized as a heart disease resulting from sequelae in acute rheumatic fever (ARF), mostly manifested in mitral regurgitation. PINP and PIIINP play an important role in triggering the remodeling process. This is a cross-sectional study. Forty RHD patients underwent echocardiographic examinations to be classified into ARF without valve abnormalities, mild, moderate, and severe mitral regurgitation. PINP and PIIINP through venous blood and ELISA were examined. The result shows a significant PIIINP level and ratio PIIINP/PINP difference between the mild and severe MR groups (p = 0.020 and p = 0.026) with insignificant PINP levels. According to the correlation test, there is a correlation between the level of PIIINP and the degree of mitral regurgitation severity (p = 0.018) with (r = 0.372) while PINP dan PIIINP/PINP ratio is insignificant. According to the study, the PINP level is indicated insignificant, but PIIINP levels and PIIINP/PINP ratio show that in RHD, children with the severe form of mitral regurgitation are significantly higher than mild regurgitation group. Thus, there is a correlation between the PIIINP level and the degree of mitral regurgitation severity in children in RHD. [ABSTRACT FROM AUTHOR]

Preterm infants need adequate nutritional intake for the faster growth process. Lack of zinc functioning in cellular metabolic processes causes growth and development disorders. One of the hormones playing a role in the growth and found to be reduced in preterm infants is insulin-like growth factor-1 (IGF-1). This study aimed to determine whether zinc supplementation had an impact to increase zinc serum, IGF-1 levels, and growth parameters in preterm infants. This study was a pure experimental study with a double-blind randomized clinical trial (RCT). This study also conducted pre and post-tests in control group. There was a significant difference in zinc serum level, IGF-1 level, and growth parameters at 3-month corrected age between the zinc and the placebo groups. [ABSTRACT FROM AUTHOR]

Kelor leaves are local food that can be used as food products because of the fairly complete nutritional content. This study aimed to determine the effect of moringa leaf puree on Moringa jelly candies' organoleptic properties and get the best formulation based on the result. This research employed an experimental study using CRD with three formulas and two repetitions. Data were tested using Analysis of Variance (ANOVA) and continued with Duncan's test. The determination of the best formulation was then calculated using the effectiveness index method. The results showed that the highest average organoleptic properties which is sensory evaluation and consumer acceptability were obtained by Moringa jelly candy with 20% moringa leaves puree. The best formulation was obtained by Moringa jelly candy with 20% moringa leaf puree with a product value of 0.84. Hence, the fortification of jelly candy ingredients by adding Moringa leaves powder (MOLP) offers an alternative model for the future development of nutritional candy and healthy food. [ABSTRACT FROM AUTHOR]

The SA-Fe2.75Mn0.25O4/Ag ferrogel has been successfully synthesized using the encapsulsion method. The crystal structure characterization of the Fe2.75Mn0.25O4/Ag material was carried out using the XRD instrument. The XRD data analysis showed the appearance of peaks of the Fe3O4 phase and the Ag phase in the sample diffraction pattern. Furthermore, the characterization of the functional group SA-Fe2.75Mn0.25O4/Ag was conducted using the FTIR instrument which the results showed that the resulting functional group bonds correspond to the wavelength range of the constituent atoms. The magnetic properties of the SA-Fe2.75Mn0.25O4/Ag ferrogel were characterized using a YSM instrument. This characterization resulted in a hysteresis curve indicating that the magnetic properties of the SA-Fe2.75Mn0.25O4/Ag ferrogel behavior as superparamagnetic. Its potential application as a material in hyperthermia therapy is characterized by using a series of magnetic induction devices that produce optimal SAR (Specific Absorption Rate) values. The SAR values of ferrogel SA-Fe2.75Mn0.25O4/Ag at a frequency of 483 and 553 Hz were 0.12 and 0.24 W/g, respectively. [ABSTRACT FROM AUTHOR]

Environmental pollution is a complex problem because waste is generated in all areas of life. If not handled properly, laboratory waste can pollute and endanger the environment. Laboratory waste containing heavy metals such as Cadmium, Chromium, Nickel, and Zinc is hazardous if it pollutes the environment. An easy and inexpensive method of treating heavy metal waste is adsorption. This research applies silica-cellulose material as heavy metal adsorbent in laboratory waste. Variations in contact time were used to measure the adsorbent capacity and adsorbent effectiveness on heavy metals Cadmium, Chromium, Nickel, and Zinc. The results showed that the contact time affected the adsorption capacity and the adsorption effectiveness of silica-cellulose on heavy metal content in laboratory waste. For Cd and Zn metals, the highest adsorption capacity at the contact time of 1 h with adsorption effectiveness values above 90%. Whereas for Cr and Ni metals, the highest adsorption capacity was at the contact time of 3 h with different values of adsorption effectiveness. For Cr metal, almost entirely can be absorbed well, while Ni metal is only half of the total metal can be absorbed. [ABSTRACT FROM AUTHOR]

The magnetic nanomaterials have attracted significant attention as effective and potential adsorbents. We synthesized the Fe3O4/MnO2/HA nanocomposite as an adsorbent for strontium adsorption. The nanocomposite was synthesized by the coprecipitation method. Humic acid (HA) is used to coat nanocomposites were obtained from the compost of TPST Supit Urang Malang City, East Java, Indonesia. HA, Fe3O4 nanoparticle, and Fe3O4/MnO2/HA nanocomposites characterized by XRD, FT-IR, VSM, SEM-EDX, and BET methods. The Fe3O4/MnO2/HA has been successfully synthesized. Coating Fe3O4 nanoparticles with MnO2/HA caused the composite size to be smaller when compared to Fe3O4 nanoparticles. The ideal situation for the adsorption of Sr2+ by the nanocomposites was 0.4 g mass of adsorbent, pH 10, and contact time of 24 hours. The pseudo-second-order model is suitable for the adsorption of Sr2+ by the nanocomposite. [ABSTRACT FROM AUTHOR]

High salt-tolerant extracellular protease is an enzyme that plays a crucial role in industries and requires high salt conditions. Some protease enzymes are not resistant to high salt conditions because they may denature under high salt concentrations. Halophilic microbes produce extracellular enzymes that are stable at high salts. This research has succeeded isolating several halophilic microbes capable of producing extracellular proteases from Bledug Kuwu, Grobogan, Central Java, Indonesia. Extracellular proteases producing bacteria screened with skim milk selective medium and purified with the quadrant streak method. Then, the pure isolate and the resulting extracellular protease were characterized BK1B isolate was a Gram-positive bacterium, while BK1D was a Gram-negative bacterium. BK1B isolate is a halotolerant bacterium and BK1D is a moderate halophilic bacterium. BK1B and BK1D had the largest proteolytic index values, capable of producing extracellular proteases with an optimal production time of three days and pH 6. Extracellular proteases from BK1B and BK1D worked optimally at pH 6 and temperatures of 45 and 42 °C with 2.541 and 3.505 U/mL activity and resistance to NaCl concentrations ranging from 3 - 13% NaCl. This suggests that extracellular proteases from BK1B and BK1D strains can be stable at high salt concentrations. [ABSTRACT FROM AUTHOR]

This study aims to analyze Brantas River's quality through the Biotilik method by utilizing macrozoobenthos as a bioindicator. The study was conducted in January 2020. Determination of the sample location was done by purposive sampling. There were three sampling stations, namely in Coban Talun, Vinolia area, and Jodipan Tourism Village (KWJ) area. Data analysis of determining the Water Pollution Index (WPI) was done by calculating the macrozoobenthos tolerance index found at each station. The Water Pollution Index in Coban Talun is three so that it is clean and mildly polluted. The identified families are Tipulidae and Baetidae. The Water Pollution Index in the Vinolia Region and the KWJ Region is 2, indicating it as dirty and rather heavily polluted waters. The discovered families are Lymnaeidae, Thiaridae, Buccinidae, Parathelpusidae, Corbiculidae, and Chironomus. Vinolia Region and KWJ Region are close to the settlement. The closer to the settlement of the water quality tends to be polluted because the water contaminated by the waste from the human activities near the river. [ABSTRACT FROM AUTHOR]

Cipadessa baccifera (C. baccifera) is a plant belonging to the Meliaceae family growing in tropical areas and containing terpenoids and flavonoids. Flavonoids have antioxidant properties so they can inhibit oxidoreductase enzyme activities, such as xanthine oxidase playing a significant role in uric acid biosynthesis. This study aimed to determine the antioxidant activity, xanthine oxidase inhibition activity, and the bioactive compounds in methanol extract and the most active fraction of C. baccifera leaves using LC-MS/MS. The research was carried out in the following steps: 1) extraction of C. baccifera leaves by maceration method using methanol solvent then phytochemical test, 2) fractions separation using solvents of n-hexane, ethyl acetate, butanol and water, 3) antioxidant and xanthine oxidase inhibition test of initial methanol extract and each fraction, 4) Identification of compounds using LC-MS/MS. The results showed that the methanol extract of C. baccifera contained alkaloids, flavonoids, tannins, saponins, and steroids. The ethyl acetate fraction had the highest levels of flavonoids, antioxidant activity, and xanthine oxidase inhibitory activity, and the LC-MS/MS analysis indicated that this fraction contained quercimeritrin, kaempferol 3-0-β-D-glucopyranoside, oxofangchirine, and glehlinoside B. [ABSTRACT FROM AUTHOR]

Vulvovaginal candidiasis occurs in 70 - 75% of women. About 40 - 45% of them experience vulvovaginal candidiasis for the second time. Approximately 70 - 89% of these infections are caused by Candida albicans. Candida albicans forming biofilm are reported to have a higher resistance to most anti-fungal drugs, including fluconazole. Objective: To determine the effects of propolis ethanolic extract (PEE) on biofilm formation and genes expression level of EFG1 on C. albicans biofilm. Methods: C. albicans biofilm formation was grown on SDB + 2% glucose and added with PEE with a concentration of 0% (control group) and 2.5, 5, 7.5, 10 and 12.5% (treatment group). Then, C. albicans biofilm formation was incubated at 37 °C for 48 hours. Biofilm inhibition was tested by the crystal violet assay. Analysis of genes expression level of EFG1 was performed using Real Time-PCR and calculated by absolute quantification method. Results: The results of the PEE effect on biofilm inhibition percentage showed a decrease in biofilm formation with the increase in PEE concentration given (p = 0.001), and gene expression level analysis showed that EFG1 (p = 0.000) expression level decreased with the increase in PEE concentration given. Conclusion: Propolis ethanolic extract could reduce biofilm formation and down-regulate the expression of EFG1 in C. albicans biofilm formation. [ABSTRACT FROM AUTHOR]