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Green synthesis of nanoparticles has many advantages over conventional physico-chemical methods and has extensive applications in the field of medicine and biology. In this study, zinc oxide (ZnO-NP) nanoparticles were synthesized from aloe vera leaf extract. 0.25M zinc sulfate was used as the zinc precursor. The presence of white precipitation from the reaction indicated the formation of ZnO-NP. The characterizations of ZnO-NP were determined using a variety of analytical methods such as X-ray diffraction (XRD), field-discharge scanning electron microscope (FESEM), ultraviolet-visible spectrophotometer (UV-Vis) and transmission electron microscope (TEM). The UV peak was formed at 380 nm while the XRD diffractogram corresponded to the JCPDS card for crystalline ZnO, confirming the presence of pure ZnO-NP. FESEM analysis revealed agglomerated ZnO-NP in irregular shapes whereas TEM showed nanoparticles with sizes ranging from 20 to 90 nm. The results of this study indicated that plant-based ZnO-NP synthesis is feasible and can be an excellent strategy for developing versatile and environmentally friendly products. [ABSTRACT FROM AUTHOR]

The main purpose of our project is to analyse the mechanical properties of friction stir welded dissimilar aluminium alloys which is Aluminium-2014 and Aluminium-7075. Welding and rotational speed are decided using trial and error method in order to get non defective welds and without any damage like crack and entirely broken. Materials which are difficult to weld by normal welding process can be welded using friction stir welding process. Material Al-2014 and Al-7075 alloy were selected for welding. These welded aluminium compounds are of a thickness of 6.0 mm using a traditional processing machine. The length and breadth of the aluminium work pieces are 100mm and 50mm. First the the two different plates are joined using friction stir welding process after that the welded parts are cut down for tensile and impact testing, and further taken for SEM analysis. After the cutting process the the separated pieces are tested against their ability to withstand how much load before breaking and their ability to acquire how much energy during their fracture,and analysed by scanning electron microscope(SEM). [ABSTRACT FROM AUTHOR]

Extrusion-based additive manufacturing (AM) suitable for printing ceramic parts is having a good practical value because of its cost-effectiveness and easy adaptability. The rheological property and printability are the essential characteristic requirement for the extrusion-based 3D printable ink. These properties will influence the quality of the printed parts fabricated using the direct ink writing (DIW) method. It is very essential to understand the above two characteristics of the ink. This work focused to understand the rheological and printability of the tricalcium phosphate (TCP) ceramic ink. In this work, TCP ceramic ink was prepared by mixing tricalcium phosphate powder and pluronic F-127 hydro-gel. The powder size was measured using a laser particle analyzer and the morphology of the powder was examined using a scanning electron microscope (SEM). Three different concentrations of solid loading such as 50 Vol. %, 55 Vol. %, and 60 Vol. % TCP inks were prepared. The rheological properties of the prepared inks were measured using a rheometer. The line study was performed using the printing parameters like pressure 3-6 bars, nozzle diameter 0.6-1.2 mm, and printing speed 5-10 mm/s. It was observed that the three different inks prepared exhibited shear-thinning behavior which is one of the essential characteristics required for extrusion-based 3D printable ink. The effects of the printing parameters like extrusion pressure, nozzle diameter, the concentration of solid loading, and print speed on the line width of a linear single line were investigated. It was observed that the increase in extrusion pressure or nozzle diameter causes an increase in the line width of the printed line. Further, the line width decreased with an increase in the printing speed at which the platform moves. [ABSTRACT FROM AUTHOR]

Composites are widely used in engineering applications because of their light weight and high strength. Studied the mechanical properties of hybrid composites has different stacking sequences of banana and hemp fiber. Composite material made with chemically treated fiber was compared with its counterpart made of untreated fiber. It was noted that the hybrid composite materials having treated fibers of BHHHB composite developed up to 1.5 times greater than tensile, flexural and impact strengths compared to its counterparts. Scanning Electron Microscope images are interpreted with the fractured surfaces of the hybrid composite materials. [ABSTRACT FROM AUTHOR]

This study aims to determine the effect of two-fabric surface positive corona plasma radiation on the characteristics of organdy silk fabrics. The plasma generator uses a plasma reactor with a point-to-plane configuration. One hundred points stainless steel needles were used as the point electrodes and served as the anode electrodes. The cathode electrode, where the organdy silk samples were placed, was made of a copper board. The sample's characteristics were analyzed using the Scanning Electron Microscope (SEM) method, the Fourier Transform Infra-Red (FTIR) method, the X-ray Fluorescence (XRF), the Mechanical strength test, and the water absorption time test. Sample irradiation by positive corona plasma discharge reduces the water absorption time and optimally after 20 minutes of irradiation. Mechanical strength testing of the organdy silk properties showed an increase in the tear resistance value of the irradiated fabrics increased compared to without irradiation at the optimum time of 20 minutes irradiation. The SEM examination showed that the surface structure changes of the fabric affect the wettability and the tear resistance of the fabric. The FTIR test showed changes in the fabric functional group structure, dominantly on O-H, C-H, C-O, and C-N compounds due to 30 minutes of plasma irradiation. Elemental composition changes of Al2O3, P2O5, and K2O were observed after 30 minutes of plasma irradiation. In conclusion, positive corona plasma radiation improves the microscopic characteristics of the organdy silk fabric. [ABSTRACT FROM AUTHOR]

Pure and Strontium doped copper oxide nanoparticles (Nps) were synthesized via chemical precipitation method. The synthesized samples were characterized using X-ray diffractometer, UV –Vis Spectrometer, Scanning Electron Microscope, Energy Dispersive Analysis of X-ray and Raman Spectral Analysis. The crystalline size and structural properties were determined using XRD. The optical properties of the samples were investigated using UV – Visible spectroscopy and Raman Spectroscopy. The SEM micrographs revealed the surface morphology. The presence of dopant samples was confirmed using EDAX measurements. [ABSTRACT FROM AUTHOR]

The conversion of glycerol into solketal becomes an interesting strategy for the valorization of glycerol as biodiesel byproduct. Acid-catalyzed reaction of glycerol with acetone is a simple mechanism for the production, and refer to this, the exploration for solid acid catalysts were attempted. In this research, a low-cost catalyst of acid-activated natural montmorillonite was prepared. The activation was performed by refluxing montmorillonite with nitric acid followed by neutralization and drying. Physicochemical characterization of the material using x-ray diffraction, scanning electron microscope, and gas sorption analyzer revealed the increasing specific surface area of montmorillonite due to the pores opening caused by acid leaching to the impurities. The change on chemical composition and pore distribution leads to the increasing surface acidity which proportionally enhance the catalytic activity. A complete glycerol conversion with the yield of 96.7 % was achieved by the reaction for 1 h at the glycerol/acetone molar ratio of 1/5 and catalyst dose of 2.5 % wt. The catalyst represents the potency of acid-activated montmorillonite for solketal production. [ABSTRACT FROM AUTHOR]

Aluminium Metal Matrix Composites with silicon carbide (SiC) particle reinforcements finding have the potential to offer desirable properties suitable for applications in engineering sectors especially transportation sectors. In this review studies, the effects of the addition SiC particle on the mechanical properties and microstructure of AC4B (Al-Si-Cu) composites produced by stir casting are discussed. The mechanical properties studies such as tensile strength, hardness, and wear behavior of composites depends on the volume fraction and distribution of the silicon carbide particle reinforcement as well as the interface between reinforcement and Al matrix. Microstructural studies will carry out by optical microscope and scanning electron microscopy. Many investigative works have been done on the mechanical properties and microstructure of Al-SiCp composites, but only a few such studies linked reinforcement parameters with mechanical properties and microstructure of AC4B(Al-Si-Cu)/SiCp composites. [ABSTRACT FROM AUTHOR]

It is a great challenge to produce a battery with electrochemical properties. Efforts have been conducted by researchers to produce batteries with good capacity and long-life cycle. In this work, a series of batteries consisted of LiFe0.5Mn0.5PO4/V/C composite cathode have been successfully synthesized via hydrothermal method with and without ultrasonic pretreatment. Lithium hydroxide, ammonium phosphate, manganese sulfate monohydrate, and iron phosphate heptahydrate were used as starting materials. Citric acid was added as both carbon source and reducing agent, and vanadium salts was added as dopant to improve the retention time for longer life cycle. Characterization was performed by scanning electron microscope equipped with energy dispersive X-ray spectroscopy for morphology and elemental composition, X-ray diffraction for crystal structure, and cyclic voltammetry for electrochemical properties. The results showed agglomerated structure for sample without ultrasonic pretreatment and fine octahedral structure for sample with ultrasonic pretreatment, a distinctive x-ray diffraction pattern and high voltage up to 4.4 V for the potential difference. More works are yet to be further done for the improvement of the capacity. [ABSTRACT FROM AUTHOR]

This study aimed to determine the effect of kerosene, sodium dodecyl sulfate salt (SDS), and sodium dodecylbenzene sulfonate (SDBS) as surfactants on zircon particle distribution in acetone solvent. The amount of each surfactant was 0.015 and 0.030 ml for kerosene and 0.015 and 0.030 gr of SDS and 0.015 gr of SDBS in 20 ml of solvent. The zircon powder was obtained from zircon natural sand from South Kalimantan, Indonesia. The phase identification, morphology, and particle distribution of the treated zircon powders were observed using x-ray diffractometer (XRD), scanning electron microscope (SEM), and particle size analyzer (PSA) respectively. The estimated crystallite size of the original zircon powder was approximately 184 nm. PSA data showed that kerosene performed a greater improvement in avoiding crystallite agglomeration as compared to the other surfactants. Zircon particles with kerosene surfactant exhibited approximately 1 crystallites while the others had 4-16 crystallites. [ABSTRACT FROM AUTHOR]

Research has been carried out to study the effect of calcination temperature in the range of 825-875 °C on the phase formation and crystallite size of tetragonal zirconia (t−ZrO2) to know when the phase transformation occurs. The raw material was zircon (ZrSiO4) powder, synthesized from the basic material of zircon sand (ZrSiO4) originating from Kereng Pangi, Central Kalimantan. Amorphous zirconia was produced from the zircon powder, which was subjected to reaction with NaOH, annealing at 700 °C for 3 hours, reaction with HCl, annealing for 1 hour at 100 °C, and titration using 10% NH4OH base. The precursors used to obtain t-ZrO2 powders were amorphous zirconia (ZR-A) and 700 °C zirconia (TZR_700). The TZR_700 precursor was obtained by heating the ZR-A precursor for 3 hours at 700 °C. Then, the ZR-A and TZR_700 powders were calcined at 825, 850, and 875 °C to produce the t-ZrO2 nanocrystals. Size and morphology characterization of the nanocrystals included XRD (X-Ray Diffraction), SEM (Scanning Electron Microscopy), and PSA (Particle Size Analysis). XRD data for all precursors and calcination temperatures showed the presence of pure tetragonal zirconia. Further analysis of XRD data showed that the crystal size increased with increasing calcination temperature, i.e., 9, 10, and 13 nm for precursor ZR-A and 10, 11, and 14 nm for precursor TZR_700 at the designated calcination temperatures. Meanwhile, PSA data showed that the average particle size of each precursor also increased with increasing calcination temperature. The scanning electron microscope (SEM) observation was in line with the results of XRD and PSA analyses. [ABSTRACT FROM AUTHOR]

The effect of milling duration and compaction method on the pore, microstructure, and hardness of sintered Ti- Cu alloy were studied. Titanium with 5wt% copper (Ti-5Cu) powder is used with milling duration 1, 3, 5, and 8 hours. Then, the powder was compacted, using hot (500°C) and cold compaction method with compaction pressure 100 bar, followed by 2 hours of sintering at 950°C. Powder Size Analyzer (PSA) was used to observe milled powder morphology. Optical Microscope (OM), Scanning Electron Microscope (SEM), Energy Dispersive Spectrometer (EDS), and X-Ray Mapping techniques were used to characterize the microstructure of the samples. The hardness of the samples was tested using the micro Vickers Hardness Test. The microstructure observation showed that all of the sintered specimens, except three samples produced by cold compaction with milling duration 8 hours, hot compaction with milling duration 5 and 8 hours, exhibit α-Ti phase and Ti2Cu which form a lamellar structure. Meanwhile, the other three samples, as mentioned earlier, revealed the appearance of intermetallic phase Ti2Cu in a scattered-separated form, rather than in a lamellar structure. In general, increasing milling duration and using the hot compaction method decreased the porosity area, pore size, and grain size, thereby increasing the alloy hardness, compared to the cold compaction method. The smallest porosity area and pore size, the finest grain size, and the highest hardness were found in sintered alloy produced by hot compaction with 8 hours milling, respectively are 1.19%, 11.02 µm, 17.39 µm, and 555.87 HV. [ABSTRACT FROM AUTHOR]

This experimental research was carried out to determine the ability of Al-doped lithium titanate (Li4Ti5O12, LTO) to function as an anode material synthesized by the facile sol-gel using lithium acetate (C2H3O2Li), titanium butoxide (C16H36O4Ti), and aluminum acetate (C4H7AlO5). All raw materials with Al contents of 1, 2, and 3 wt% were stoichiometrically dissolved in ethanol solutions using hydrochloric acid as a catalyst. After aging for 72 h, the precursors were sintered at 900°C for 2 h in air atmosphere. Furthermore, the effect of Al-doped on the crystal structure of LTO was studied using X-ray diffraction, while the morphology, size, and element of the sample were measured using scanning electron microscope (SEM). The cyclic voltammetry and capacity of the samples were investigated using the galvanostatic techniques in a half cell. The result of phase analysis showed the presence of LTO and rutile structures as impurities. In addition, the SEM images showed that the particle was in irregular form without porous observations. The average particle size of 6 mm was measured using image-J software, while the increase in dopant on the LTO structure led to the enhancement of the diffusion coefficient of Li-ion. Based on these characteristics, the spinel LTO provided an initial capacity of more than 100 mAhg−1 after charge-discharge at the rate of 0.1 C in range potential 0 – 3 V. [ABSTRACT FROM AUTHOR]

Carbon Nanotube (CNT) is a material known to have a high thermal conductivity. Therefore, CNT is widely used for heat transfer applications. One of the CNT applications in heat transfer is to make nanofluids. CNT is a cylindrical molecule consisting layers of single layer carbon atom sheets (graphene). CNTs can be single walled (SWCNT) or multi-walled (MWCNT). In this study, MWCNT was used and characterized by using Scanning Electron Microscope (SEM). CNT-based nanofluids were synthesized by adding 0.01%, 0.03%, and 0.05% of CNT particles as well as 10%, 20%, and 30% Polyethylene Glycol (PEG) surfactants into distilled water. The objective of surfactants addition was to maintain the stability of nanofluids. The addition of PEG surfactant concentrations by 20% and 30% decreases the thermal conductivity of nanofluids. On the other hand, the stability of CNT-based nanofluids increases after the addition of PEG surfactants. [ABSTRACT FROM AUTHOR]

Aluminum dross has a low aluminum metal content, so it may be served in making concrete. The addition of aluminum dross is expected to improve the concrete passive layer, contributing to corrosion control. This research investigates corrosion behavior of reinforced bar embedded in concrete with aluminum-added in the immerse condition by seawater. The impact of chloride ion exposure on the reinforced bar will be characterized by electrochemical impedance spectroscopy and potentiodynamic polarization. The microstructure evolution due to time exposure and chloride ion content could be explored by scanning electron microscope. Corrosion resistance on the reinforced bar tends to increase with aluminum dross presence. The consequences demonstrate the significant influence of aluminum dross on the passivation area and corrosion behavior of concrete. [ABSTRACT FROM AUTHOR]

Cellulose produced from bacteria is a biopolymer that having high strength, purity and permeability so that it can be applied in various fields. The study aims to observe the morphology and structure of BC after being treated by a chemical reagent. The study was conducted using a BC pellicle that was produced from an extract of pineapple peel waste after being fermented for 10 days by Acetobacter xylinum. BC pellicle was treated by a chemical reagent solution (BmimCl, H2O2, and NaOH) by a concentration of 5%. BC pellicle was immersed in chemical reagent at 80 °C for 2 hours then dried in an oven for 6 hours at 70°C. The morphology observation was conducted under the Scanning Electron Microscope, and the structure was analysed using XRD apparatus. The results indicate that diffractogram of BC film after chemical pretreatment, the crystal size of BC film reduce from 10.01 nm (without treatment) to 3.67 nm, 3.62 nm, and 3.68 nm for pretreatment fo NaOH, H2O2, and BmimCl, respectively. The highest crystallinity of BC film was obtained by pretreatment using H2O2 with a crystallinity of 76.83%. The morphology of BC film indicated that pretreatment using NaOH, H2O2, and BmimCl cause peel of BC nanofiber so that the surface of BC film looks rougher and more porous. [ABSTRACT FROM AUTHOR]

Nanofluid is of great attention because of the physical properties and the effective thermal conductivity. Many applications of nanofluids are in improving the performance of heat exchangers. This study aims to measure and analyze the thermophysical properties of SWCNTs. Concentrations used in nanofluids are 0.1%, 0.3%, and 0.5% with distilled water as the base fluid. The process of nanoparticle characterization SWCNTs is done by testing the thermal conductivity and specific heat using C-Them TCI (thermal conductivity analyzer), viscosity test using a viscometer NDJ-8S, density test using a density meter, METTLER toledo, test FTIR (Fourier Transform Infra Red), XRD (X-Ray Diffraction) test, and SEM (Scanning Electron Microscope) test. SWCNTs have high mechanical strength, thermal conductivity and good electrical conductors, structure and strength of high appeal. SWCNTs nanofluids showed an increase compared to distilled water in various variations. [ABSTRACT FROM AUTHOR]

A novel bio-composite of bacterial cellulose (BC) and galactomannan Arenga pinnata Merr (GA) has been synthesis using Acetobacter Xylinium in coconut water media containing fertilizer. A foamed hydrogel bio-composite occurred after 7 days which was then soaked in different concentrations of ethanol solution (70, 96 and 100%) followed by drying in a desiccator under vacuum condition to produce white thin paper with the thickness varying from 0.325 to 0.700 mm. The surface morphology of the bio-composite was studied using scanning microscope electron which showed that GA molecule could cover BC holes rendering decreasing holes size. The swelling property of bio-composite was determined in water, simulated intestinal fluid and simulated gastric fluid. The result indicated that increasing GA could increase swelling properties. The functional group of bio-composite BC/GA did not change based on infra-red spectroscopy. Therefore it can be concluded that bio-composite BC/GA presented suitable properties to be used as a drug carrier. [ABSTRACT FROM AUTHOR]

Polyaniline is a conductive polymer that possesses a high attenuation level, making it suitable for electromagnetic interference shielding applications. In this work, a film of emeraldine phase polyaniline was synthesized, and its microwave absorbing properties were studied. The polyaniline was prepared using the oxidative polymerization method. A Fourier transform infrared spectrometer and an X-ray diffractometer were employed to confirm the formation of the emeraldine salt polyaniline. A scanning electron microscope showed flaky particles of the as-prepared polyaniline. The microwave absorption test carried out on a vector network analyzer showed a remarkable response in the frequency range from 9.5 GHz to 11.4 GHz, with the highest reflection loss value of -15.6 dB reached at 10.1 GHz. This result shows the potential for polyaniline applications to be developed for X-band absorber materials. [ABSTRACT FROM AUTHOR]

The development of successful green chemistry techniques for the synthesis of metal nanoparticles has become a major focus of researchers in recent years in order to find an eco-friendly technique for the processing of well-characterized nanoparticles. Metal nanoparticles are gradually becoming attractive in their synthesis and application. In this study, the green synthesis of silver nanoparticles (AgNPs) from silver nitrate (AgNO3) using the extract of Polygonum minus leaves as a reducing agent differed in pH and temperature. The biosynthesized Polygonum minus silver nanoparticles (Pm-AgNPs) were characterized using different techniques, such as UV−visible spectroscopy, Scanning electron microscope (TEM) and energy-dispersive X-ray analysis (EDX). The results showed an increase in the rate of formation of silver nanoparticles with increasing temperature, and the absorbance increases monotonically indicate that the alkaline pH is more favorable for the synthesis of AgNPs at pH equal to 8. The observation of TEM showed a well-dispersed silver nanoparticle with roughly spherical shape and size ranging particle size 6 – 21 nm. The EDX analysis provided a strong signal in the synthesized nanoparticles at 3 keV from the silver atoms, which verified that the AgNP synthesis was successful. The synthesized silver nanoparticles have antimicrobial properties which showed, an inhibition zone for two Gram-positive and two Gram-negative bacteria and it is proven by low of MIC value ranging 31.25 – 100 µg/ml while MBC in range 62.5 – 100 µg/ml. The Klebsiella pneumoniae has better result compared Staphylococcus aureus, Escherichia coli and Bacillus subtilis. [ABSTRACT FROM AUTHOR]

The structure and phase of magnetite nanoparticle of iron sand from Bayuran beach was determined by X-ray diffraction and Fourier Transform Infrared (FTIR) spectroscopy. Surface morphology of the obtained magnetite nanoparticle was observed by Scanning Electron Microscope (SEM) and the compositional elements was determined by Energy dispersive X-ray diffraction (EDX). Last for the effectiveness of adsorbent materials based on magnetite nanoparticle obtained was analyzed using atomic absorption spectroscopy. Based on the result of XRD characterization, the magnetite nanoparticle was obtained has polycrystal structure with magnetite, Fe3O4 phase is dominant with crystallite size is around 30.08 nm. This result also supported by FTIR spectroscopy which is the absorption peaks of Fe-O bond had highest intensity at 2370.7; 3405.27; 3783.26 cm−1. It's also supported by EDX analysis, which is the mass percentage of Fe, O and FeO element was 54.55%, 25.00%, and 70.17%, respectfully. From the SEM analysis shows arough round and agglomerated morphology of magnetite nanoparticle was obtained with average particle size of ∼30 nm. This result is similar to XRD analysis of crystallite size. The order of effectiveness in reducing of PB level on the water pollution in Tegalrejo river, it done by using 3 form of magnetite nanoparticle i.e. powder, electrolyzed caplets and caplet. The result of AAS analysis, the powder form of magnetite nanoparticle is more effective to reduce the Pb metal in water pollution, the as followed by electrolyzed caplet and caplet of 88.59%, 82.47% and 78.52%, respectfully. Based on the result, can be concluded the coprecipitation method has been proven to produce magnetite nanoparticle that are effective as Pb metal adsorbent in water pollution. [ABSTRACT FROM AUTHOR]

The aim of this study was to analyze the microstructure of cheeses before and after drying using preliminary coloring. The objects of research were cheeses of the following brands: "Pokrovskiy", "Russian" and "Gollandskiy". Drying of cheeses was carried out in a vacuum drying unit at a residual pressure of 7-8 kPa, a heat flux density of 5±0.5 kW/m2, and a heating temperature of 50±1 °C. Photographs of the microstructure were obtained on a scanning electron microscope JEOL JSM-6390 LA. Two methods were used to stain the fat of cheeses before microstructural analysis: Sudan according to Gersheimer; Sudan III and methylene blue. In colored cheeses in any of the ways, in comparison with uncolored cheeses, their structure becomes more clearly visible during electron microscopy. In the structure of cheeses, fatty elements are present in the form of irregular droplets, ranging in size from 30 to 100 microns. It was found that the structure of cheeses stained with Sudan III and methylene blue is clearer and more pronounced in comparison with the structure stained with Sudan III according to Gersheimer. Since fat melting occurs when dyeing dry cheese with Sudan III according to Gersheimer, this technique cannot be used for dyeing fat in dry cheeses. It is recommended to stain the fat in dry cheeses with Sudan III and methylene blue. In stained cheeses, the size of calcium phosphate before drying was determined from 5 to 10 microns, in cheeses after drying from 30 to 100 microns. [ABSTRACT FROM AUTHOR]

Low-temperature hybrid gas diffusion heat treatment process on austenitic stainless steel will result in the S phase layer formation. This work focuses on the influence of temperature towards the S phase layer development on ASTM F138 stainless steel using a hybrid gas diffusion process. The hybrid process performed at different temperature of 400°C, 425°C, 450°C, 475°C and 500°C for 6 hours of treatment time. Meanwhile, the gas composition of NH3, CH4 and N2 is maintained at 80%, 10% and 10%, respectively. Based on the XRD and micrograph analysis from the scanning electron microscope, as the treatment temperature increase, the S phase layer thickness increases. The maximum layer thickness obtained is 10.1µm at a treatment temperature of 500°C however, the XRD analysis confirms the attendance of chromium nitride precipitation, which will deteriorate the corrosion resistivity of the heat-treated material. At 400°C, no visible S phase layer is found, and the uniform S phase layer can be obtained at a temperature above 425°C. In conclusion, the suggested treatment temperature for the low-temperature hybrid gas diffusion heat treatment process for industrial application should starts at 425°C to 475°C to maintain the S phase layer uniformity and avoid the traces of chromium precipitation. [ABSTRACT FROM AUTHOR]

Nannofossil analyses of this study was carried out of Kalibeng river section, Plandaan, Jombang, east Java. This study included of the Kendeng Zone, East Jawa Basin. This research method through 2 section of the Measurement Section, and sampling a number of 32 samples. Analysis used of smear slide and Scanning Electron Microscope analysis. The result of the analysis of there are twelve genera and forty-three species. The stratigraphy of this area consists of 3 lithostratigraphic units, namely from old to young: Marl Unit of Kalibeng Foramtion (CNM20-CNPL6/Late Miocene to Early Pliocene), Calcareous Sandstone Unit of Sonde Formation (CNPL6-CNPL8/Late Pliocene to Pleistocene), and Calcareous claystone unit of Sonde Formation (CNPL9-CNPL10/CNPL11?/Pleistocene. The nanoplankton biostratigraphic zone are arranged into 11 zones consisting of 2 Partial Zones, 10 Interval Zones. Development of sedimentation rate (RoS) of this study, there are 11 periods. The periods are (1) CNM20 Zone/Late Miocene to Early Pliocene /1.4 cm/ky), (2) CNPL1 Zone /Early Pliocene (8.44 cm/ky), (3) CNPL2 Zone/Early Pliocene (9.7 cm/ky), (4) CNPL3 Zone/Late Miocene-Early Pliocene (90.91 cm/ky), (5) CNPL4 Zone / Late Miocene-Early Pliocene (4,26 cm/ky), (6) CNPL5 Zone/Middle-Late Pliocene (8.57 cm/ky), (7) CNPL6Zone /Late Pliocene (13,26 cm/ky), (8) CNPL7 Zone/ Late Pliocene to Early Pleistocene (14.95 cm/ky), (9) CNPL8 zone /Early Pleistocene (26.42 cm/ky), (10) CNPL9 Zone/Early Pleistocene (3.11 cm/ky) (11) CNPL10 Zone/Early-Middle Pleistocene (1.34 cm/ky). In this study there is a fast sedimentation process, namely in the CNPL3 Zone which has a sedimentation rate of (90.91cm/ky), very thick thickness sedimentasion (200 m) and with a short time duration of (0.22 my). There are 2 unconformities, namely Top of the CNPL2 Zone (Late Miocene) and Top of CNPL7 Zone (Early Pleistocene) [ABSTRACT FROM AUTHOR]

The butterfly pea flower (Clitoria ternatea L.) is a plant that is easy to grow and useful in the culinary and health fields. It offers various benefits for the human body due to its bioactive components, such as flavonoids, anthocyanins, and flavonol glycosides. Processing butterfly pea flower into tea is one of the convenient ways to consume and extend the shelf life of the flower. This study investigates the effect of different drying methods, namely greenhouse effect drying, cabinet drying, and freeze-drying, on changes in dried butterfly pea flower's physical and chemical properties. The material used in this study was fresh flowers obtained from local farmers in Kepuh Kulon, Wirokerten, Banguntapan, Bantul, Yogyakarta with an average moisture content of 88.82% w.b. The experimental design uses a variation of seven drying methods, that is, greenhouse effect drying, cabinet drying at 50 °C, cabinet drying at 60 °C, cabinet drying at 70 °C, freeze-drying at 40 °C, freeze-drying at 50 °C, and freeze-drying at 60 °C. Parameters investigated were temperature profile, dimensional shrinkage, moisture content, color, total phenolic compounds, and photo microstructure analysis using Scanning Electron Microscope (SEM). The experimental results showed that the freeze-drying treatment at 40 °C was the optimal treatment with a total phenolic compound of 23.195 mg.GAE/g, a color change in the Euclidean distance (ΔE) 29.11%, moisture content of 6.09% w.b., a length shrinkage of 22.12%, 36.47% width shrinkage, 29.59% thickness shrinkage, and the lowest cell wall shrinkage appearance on microstructural photo analysis using Scanning Electron Microscope (SEM). [ABSTRACT FROM AUTHOR]

The widespread spread of skin cancer all over the world was impulse to researchers for trying the discovery of effective drugs including detection of the nanomaterial that contribute to its elimination. Zinc Oxide Nanoparticles (ZnO-NPs) were prepared by chemical lysis and sol-gel method and then examined by X-ray diffraction and using scanning electron microscope (SEM). Cytotoxicity assays were also examined ex vivo to determine the toxic effect of ZnO-NPs at different concentrations (6.25-100 µg/ml) on melanoma cells using the cancer line A-375, and compared it with the normal line Human foreskin fibroblast cells (HFF). The obtained results were within the nanoscale, spherical shape, and size ranged between (37-62 nm). In addition, the cytotoxicity results showed the presence of an inhibitory activity affecting the growth of cancer cells, and there were no significant differences when exposed to ZnO-NPs on the normal line HFF. From the above, we conclude that there are promising results for a successful treatment to eliminate skin cancer using ZnO-NPs as an unconventional material used in cancer treatment. [ABSTRACT FROM AUTHOR]

WO3 nanorods with loose inter-grain density have been successfully fabricated by the low-cost hydrothermal method. In addition, the capping agent significantly affects the morphology and the sensing mechanism of the WO3 sensor. The as-synthesized WO3 powder was tested for its morphology, structure, and phase using a scanning electron microscope (SEM) and X-ray diffraction (XRD). The sample WO3 has polycrystalline properties with a monoclinic crystal structure. The ethyl glycol monomethyl ether (EGME) acts as a structure-directing agent in the nanorod formation with the loose density of the WO3 sample. The nanorod form of WO3 produces a high gas response value of 68.4 to 2 ppm of NO2 gas at a quite low operation temperature of 150 °C. The morphology of WO3 modified by EGME supports the gas response characteristics of the WO3 sensor to NO2 gas. The sensor test results show that WO3 with nanorod morphology with a loose density can be a good base for NO2 gas sensors to be applied. [ABSTRACT FROM AUTHOR]

Sound absorption characteristics of Oil Palm Empty Fruit Bunch (OPEFB) bound together by chitosan are investigated by an experimental approach. The usage of OPEFB for the sound absorber application is useful for obtaining natural fiber-based absorbers while the issue of oil palm plantation waste in Indonesia to the environment can be alleviated. Moreover, with the chitosan bio-binder, targeted porosity structures in form of kinematic and non-kinematic porosities are expected to be present to deal with the performance at low frequency. Here, we investigate the presence of both porosity types using the Scanning Electron Microscope (SEM) technique while associated sound absorption characteristics are obtained by the impedance tube measurement under normal sound incidence. The relations of the structure and resulting sound absorptions are discussed. [ABSTRACT FROM AUTHOR]

Bran oil, commonly called Rice bran oil (RBO), is extracted from rice bran using a volatile solvent. RBO extract is reported to have poor stability against the heating process. Therefore it is necessary to increase the stability to protect its benefit. Many environmentally friendly methods are being developed in storing food, including the application of microencapsulation. Microencapsulation is a process in which a thin coating polymer envelopes small solid particles or liquid droplets, and the particle size ranges from 1-5000 µm. This research aims to study the effect of the addition of emulsifier Tween 20 on rice bran oil microencapsulation using natural polymers kappa-carrageenan and chitosan as encapsulants coacervation method. Microencapsulations were analyzed by Fourier Transform Infra-Red Spectrophotometer (FTIR), Scanning Electron Microscope (SEM), encapsulation efficiency, and yield. In this study, two Tween 20 emulsifier volume variations were used, namely 0.5 mL and 1 mL. Results show that obtained particles have an appearance that is not different. The surface is uneven, structured, and aggregated. RBO was successfully loaded on the matrix chitosan/carrageenan, as can be seen on FTIR spectra. However, for the addition of 0.5 mL, Tween 20 particles had a wider, structured, and finer morphology and had a higher encapsulation efficiency of 66.4959%. The higher the Tween 20 concentration, the more microencapsulations formed, which may break, resulting in lower efficiency. The yield of microencapsulations obtained was 91.9563 for 0.5 mL Tween 20 and 92.2781 for 1 mL Tween 20. [ABSTRACT FROM AUTHOR]

The most commonly used part of the fish body is meat, while the bone is more often not utilized despite the fact that it contains hydroxyapatite (HAp). HAp minerals as the main constituent of inorganic parts in fish bones have been widely studied for their use as material for bone tissue engineering and for pollutant adsorbent. Moreover, modification of this HAp containing material has also been studied to obtain materials with superior properties such as photocatalytic material. In this research, fish bone was converted into photocatalytic material which is able to degrade methylene blue (MB) dyes. The starting materials were bones of red snapper and skipjack tuna. The bones were dried, calcined at 600 °C and 1000 °C, and ground. The products were then treated in a silver nitrate solution, rinsed, and dried. The materials obtained were analyzed by using the X-ray diffraction (XRD) technique for phase composition determination and Scanning Electron Microscope (SEM) to explore the morphology. Photocatalytic activity of the materials obtained from the red snapper was then confirmed by applying them to MB photodegradation under visible light. The XRD diffraction patterns showed typical characteristics for the bones of each species. Phase identification of the patterns showed that not all the material has metallic silver incorporated. On the other hand, all the materials produced by this new procedure contained silver phosphate (Ag3PO4) which is known as visible light photocatalyst. The photodegradation experiment confirmed that most MB was degraded under visible light by materials produced by calcination of bone at 600 °C. [ABSTRACT FROM AUTHOR]

Ti-6Al-4V is the most common titanium alloy for implant application. However, Ti-6Al-4V has disadvantages that this alloy's vanadium element. Vanadium is a toxic element and may cause potentially serious health problems. In this study, Vanadium was substituted with Niobium to obtain an alpha/beta titanium alloy which is safe for use in the human body as an orthopedic material. The Hot Rolling process carried out Ti-6Al-6Nb to improve its mechanical properties. Hot rolling is carried out at 900, 1000, and 1100 °C temperatures. Microstructural observations with optical microscopy (OM), scanning electron microscope (SEM), and hard tests were carried out to observe changes in microstructure and hardness after melting, homogenization, and hot rolling processes. The study revealed that hot rolling at 1000 °C has the lowest hardness, and rolling at 900 °C has the highest hardness value. The finer grain size most influenced to the increasing hardness value of hot rolled Ti-6Al-6Nb. [ABSTRACT FROM AUTHOR]

A study on photocatalytic degradation of nata de coco wastewater have been carried out using a TiO2 nanotube (TNT) catalyst modified with Pt metal and immobilized on fluorine-doped tin oxide conductive glass (FTO) using a drop of TiO2 sol containing Ti(OBu)4 and polyethylene glycol, followed by calcinations at 450 °C. The synthesis result was characterized by FTIR and scanning electron microscope. The catalyst was put in a batch reactor containing liquid waste and irradiated by visible light. The occurrence of degradation was indicated by decrease in the value of COD (chemical oxygen demand), ammonia, and acetic acid of liquid waste. The decrease of COD value reached 58% at a concentration of Pt 65 mM. The shift in absorption from UV to visible light was indicated by the activity of the Pt-modified catalyst being greater than that of the unmodified catalyst. Measurement variations of irradiation time on waste degradation were also carried out to determine the optimum time of photocatalytic degradation [ABSTRACT FROM AUTHOR]

Polymer based hybrid composites offer balanced strength/stiffness, improved fatigue/impact resistance, fracture toughness, reduced weight and/cost. These composites can be used to meet the specific design requirements in a more cost-effective way than that of mono-composites. This research article mainly focuses on preparation, mechanical properties and erosion behaviour of silicone rubber (SR) modified polyoxymethylene (SR/POM) blend with reinforcements namely polytetrafluoroethylene (PTFE), aramid fibers, and molybdenum disulphide. Mechanical test results indicated that there is marginal increase in hardness with the addition of hybrid reinforcements in SR/POM blend. The maximum values of tensile, flexural strength and impact strength was measured for SR/POM blend with PTFE/SAFs reinforcing agents. Addition of hybrid reinforcements enhanced all mechanical properties except % elongation of break. The SR/POM blend sample with 5 wt. % PTFE, 15 wt. % aramid fibers and 2 wt. % MoS2 exhibit the greatest tensile modulus (2990 MPa) and excellent flexural modulus (3385 MPa). Erosion test results revealed that these hybrid SR/POM based composites showed semi ductile erosion behaviour, with maximum erosion rate at 45° impingement angle. Finally, eroded surfaces of SR/POM and their hybrid composites were characterized using scanning electron microscope. [ABSTRACT FROM AUTHOR]

Aluminum alloys are used primarily to produce rings, structural components, automotive systems, and aerospace components. Fusion welds are difficult to perform on these alloys due to their poor joint efficiency, solidification cracking, and alloy segregation in aluminum joints. Thus, solid-state welding techniques are preferred for their higher performance with fewer defects, as well as their eco-friendliness. In the present study, solid-state friction stir welding (FSW) process is used for joining dissimilar aluminum alloys AA5083/AA6061. Weld specimens were fabricated for dimensions of 150 x 150 x 6 mm. The rotational speed, the transverse speed, and the tilt angle were set to 1000 rpm, 25 mm/min, and 2°, respectively. The welded specimens were evaluated for their microstructural and mechanical properties. The mode of failure was observed by scanning electron microscope (SEM). As a result, the dissimilar joints showed a maximum tensile strength of 194.3 MPa and a maximum hardness of 86 Hv in the nugget zone. The maximum hardness was caused by recrystallizing grains in the nugget zone, and the rupture occurred at the heat-affected zone (HAZ) on the retreating side. [ABSTRACT FROM AUTHOR]

Cemented carbide is a hard substance that is commonly used in industry. Brazing is used to bond cemented carbide to steel. Several factors, such as the filler metal, influence the joining of cemented carbide to steel. The interfacial microstructure and mechanical behavior of cemented carbide and steel materials connected by brazing are investigated in this work. Silver-based filler metals are used in the joining process, which is done using an oxyacetylene flame. A scanning electron microscope is used to examine the microstructure of the brazed region (SEM). Energy dispersive spectroscopy is used to identify the element component (EDS). A universal testing equipment is used to perform the shear test. A MicroVickers hardness machine is used to determine microhardness. Cu-Phase solid solution, Ag-Phase solid solution, and AgCuZn eutectic phase make up the microstructure. The mechanical behavior of the joint shows significant results. The shear strength reaches 120.9 Mpa, and the hardness in the brazed area is 112.73 VHN. [ABSTRACT FROM AUTHOR]

Synthesis of graphene electrodes modified TiO2−Calix[4]Arene (G@TC) has been successfully carried out using a mechanical homogenization method. Electrodes were characterized using Scanning Electron Microscope (SEM) and detection of Cu2+ ion using cyclic voltammetry. Based on SEM analysis, results show that the G@TC electrodes are composed of rough surfaces with different grain sizes and have a dense structure with small pores. G@TC electrodes showed good voltammetric performance in the measurement of Cd2+ ions. In this case it occurs at optimum conditions, including the use of Calix[4]Arene of 0.015 g and citrate buffer with pH=5. During the measurement, a reversible reaction occurs with both an oxidation potential (Epa) and a reduction potential (Epc) for the Cd2+ ion are 0.19 V and 0.25 V, respectively. [ABSTRACT FROM AUTHOR]

Corn husk waste possesses a relatively high silica content which can be utilized as the raw material to produce useful silica compounds. In this study, natural silica aerogel was synthesized from corn husk using a combination of sol-gel and cationic exchange methods under ambient pressure drying conditions with the help of MTCS as a surface modification agent. This study aims to determine the feasibility of the synthesis method and the physical properties of the as-synthesized silica aerogel. The purity and crystallinity of silica aerogels were analyzed using Fourier Transform Infrared (FTIR) and X-ray Diffraction (XRD), while its morphology was examined using Scanning Electron Microscope (SEM). The optimum synthesizes parameters of silica aerogel were observed at cation resin to sodium silicate filtrate ratio of 2:1, with the addition of 0.4 ml MTCS and drying under ambient pressure at 60°C for 4 hours, continued by 120°C for 2 hours. The as-synthesized silica aerogel possesses high purity, with an amorphous crystal structure and yield of 46.44 wt.%. Silica aerogel also has a porous morphology with pore diameters ranging from 1 to 3 μm. [ABSTRACT FROM AUTHOR]

Natural gelcoat was prepared from carrot waste powder as a coloring and strengthening material to epoxy by mixing it with different weight ratios (1, 2, 3, 4, 5, 6, 7 and 8%). The effect of the particle size of the micro Carrot powder was studied, using two different sizes (0.5 and 0.25 microns) on the mechanical properties (impact, flexural and hardness) and thermal conductivity. The impact strength increased from (10.09 KJ/ m2) for neat epoxy to (13.44 KJ/ m2) for epoxy with 2% of 0.5 MCF and to (18.86 KJ/ m2) for epoxy with 1% 0.25 MCF, flexural strength increased from (41.94 MPa) for neat epoxy to (∼ 64 MPa) for epoxy with 2% of 0.5 MCF and to (82.38 MPa) for epoxy with 1% of 0.25 MCF, hardness of neat epoxy was (∼ 76) and almost maintains its value for epoxy with 2% of 0.5 MCF and for epoxy with 1% of 0.25 MCF. The internal structure of these composites was also studied using a scanning electron microscope, to explain the superiority of the (EP/ 0.25MCF) over the other composite (EP/ 0.5MCF) in all mechanical properties in addition to thermal conductivity, using EDX technique the ratios of elements composition are determined of the epoxy composites this ratios was linked with the color of the composites. Finally the diffusion of water in epoxy/ sub microns carrot fibers (EP/ 0.5MCF) and (EP/ 0.25MCF) composites have been determined for six weeks of immersion. [ABSTRACT FROM AUTHOR]

This study involves the preparation of polymer matrix composite by the hand lay-up process, using unsaturated polyester resin (UPR) as a matrix and waste aluminum flakes as reinforcement material in different weight fractions (0, 10, 30, 40 and 50%) wt. of aluminum. All samples were subjected to bending, tensile, hardness tests and the scanning electron microscope (SEM) of fractured samples surface was also conducted. It was found that 10% wt. is the best reinforcement ratio in tensile, hardness and Young's modulus tests, and (SEM) shows there is a good distribution at 10 % of Al flakes inside the matrix, and the polyester covers the fillers completely which denotes a good interstitial adhesion between them. [ABSTRACT FROM AUTHOR]

This study investigate the Epoxy performance after reinforcing with Jute fibers. Before reinforcement process, the natural jute fibers were immersed in three different concentrations of acetic acid (1%, 5%,10%) for one hour, then epoxy composites were made from these treated fibers in a way that the weight fraction of jute fibers is 30% also other samples of composite were made from epoxy but with untreated jute fibers. Upon making the reinforced composites, different mechanical properties were tested, namely shore-D hardness, roughness, shock resistance and a Scanning Electron Microscope (SEM) examination for the samples that had been subjected to the impact test in order to examine the fracture surface of those samples. This study proved that when epoxy reinforced with 30% of natural untreated jute fibers to a bout 30% increase in the impact strength of the composite. [ABSTRACT FROM AUTHOR]