bluuebunny/crossref_metadata_2025_split huggingface dataset:
Characterization of activated charcoal from sugar palm bunches (Arengga pinnata (Wurmb) Merr) and the application as adsorbent lead (Pb), copper (Cu) and chrome (Cr) in solution
Authors: Adrianto N , Mongkito V H R , Fayanto S , Anas M , Eso R 
Published: November 2019

Abstract
This study proposes to determine the ability of activated charcoal from sugar palm bunches (Arengga Pinnata MERR) as lead adsorbent (Pb), copper (Cu) and chromium (Cr). The sample was carbonated with a temperature of 200-400°C, then mashed by using mortal and sieved using a size of 100 mesh. Samples were activated with activation temperature variations of 600°C, 700°C, and 800°C and characterized using Scanning Electron Microscope (SEM) with 2500x magnification and Atomic Absorption Spectroscopy (AAS). The SEM results indicate surface morphology of the best-activated charcoal of at a temperature of 700°C with uniformly distributed pore size. In the AAS analysis results obtained for Pb absorption capacity of 0.0082 mg/g and absorption efficiency of 86.86%, the Cu absorption capacity of 0.0203 mg/g and absorption efficiency of 94.37% and Cr adsorption capacity of 0.0243 mg/g and efficiency absorption 96.39%. The value of absorption capacity obtained the result of AAS characterization, and the best adsorption efficiency was at 700°C.
Modeling response Time Lapse Microgravity Vertical Gradient (TLMVG) anomaly due to fluid volume changes of sub surface and its implementation in Kota Lama Semarang
Authors: Supriyadi  , Khumaedi  , Sugiyanto  , Ikhsan M , Sarkowi  
Published: November 2019

Abstract
Modeling of time lapse microgravity anomaly have done. The modelling was done with two ways are first gravimetri position on the earth’s surface, and second position at a height of 25 cm from it. The first model shows for 30 % rock porosity than any change in groundwater within depth 1 meter causes gravity change 12,579 μGal. The second model show that reduction of groundwater wil reduce time lapse microgravity vertical gradient (TLMVG) anomaly. Reduction of groundwater will provide TLMVG negative value (-) and reverse groundwater give positive value (+). It was concluded that in the Kota Lama during the range of March to September there was no subsidence, but there was a decrease in groundwater level of 1.449 m
Fabrication and characterization of Polymer Optical Fiber (POF) based on Mach-Zehnder interferometer for temperature sensor
Authors: Rumiana H , Maimanah S , Kurniansyah K E , Yulianti I , Putra N M D 
Published: November 2019

Abstract
A polymer optical fiber based on Mach-Zehnder Interferometer (MZI) was proposed and experimentally demostrated for temperature sensor. The MZI comprises two couplers with length of 2 cm and two POF branches with different length which are 5 cm and 3 cm. The jacket of the 5 cm branch was removed to increase the temperature effect on the MZI. Characterization of the sensor was done by putting the sensor in temperature chamber while the two ends of the MZI were connected to light emitting diode (LED) and spectrometer, respectively. The temperature was varied from 40°C to 80°C with an increment of of 5°C. The results showed that the sensitivity is 0.0822 nm/° C with correlation of 97,66%. The MZI sensor has the highest accuracy at temperature of 55°C and the lowest accuracy at temperature of 70°C.
Photoluminescence study of ZnO:Al thin films with different power plasma
Authors: Astuti B , Sugianto  , Maftuchah I , Firmahaya N A , Marwoto P , Ratnasari F D , Muttaqin R , Setyaningsih N E , Aryanto D , Isnaeni  
Published: November 2019

Abstract
ZnO doped Al (ZnO:Al ) thin film was deposited on corning glass substrate using DC magnetron sputtering method. Depositon process of the ZnO:Al thin films was kept constant at Argon pressure, deposition temperature and deposition time are 500 mTorr, 400°C and 2 hours, respectivelly. Furthermore, for deposition process has been done on the variation of power plasma are 33, 43, and 50 watt. For the optical properties of the ZnO:Al thin films using Photoluminescence spectroscopy. Different plasma power will affecting on ion energy and momentum pounder. It’s effect on the quality of thin films that influence to photoluminescence intensity was obtained.
The adsorption of dye waste using black carbon from polyethylene terephthalate (PET) plastic bottle waste
Authors: Rahmawati I , Priyanto A , Darsono T , Sulhadi  , Aji M P 
Published: November 2019

Abstract
Black carbon from PET plastic bottles has been successfully synthesized by heating methods. Six gram sample of PET plastic bottle were heated by furnace for 2 hours with various heating temperature as 300°C, 350°C, 400°C, and 450°C. Black carbon then mixed with methylene blue in aqueous solution with various masses as 20 mg, 40 mg, 60 mg, 80 mg, and 100 mg. This study shows that the black carbon which synthesized at temperature of 450°C performs as the most effective absorbent. The solution of methylene blue changed its color significantly and became clearer after the adsorption process. The absorbance spectra of methylene blue lies at the wavelength of 550-700 nm and decreasing the absorbance intensity. It indicates that the concentration of methylene blue is decreased during adsorption proccess which predicted due to the oxygen molecul and the porosity. The analysis of carbon morphology showed that black carbon which synthesized at temperature of 450°C has more pores, while the black carbon which heated at temperature of 400°C has few pores. The EDX analysis shows that black carbon that heated at temperature of 450°C contains 32,4% oxygen, whereas black carbon that heated at temperature of 400°C contains 24,3% oxygen.
Chi-Squared test for constraining free parameters of modified Gravity on Brown Dwarfs
Authors: Rosyadi A S , Sulaksono A 
Published: November 2019

Abstract
Constraining free parameters of two modified gravity theories such as beyond Horndeski and Eddington Inspired Born-Infeld Theories of Gravity have been done precisely with LHS6343C data. However, it remains insufficient to explain the radius and mass relation of Brown Dwarf globally. We still need to identify how well beyond Horndeski and Eddington Inspired Born-Infeld Theories of Gravity being compared by the completed observation mass-radius data of Bayliss et. al. The provided data gives error-bar that can be used to study more systematically through the standard deviation analysis. We do Chi-Squared test to obtain minimum value on the free parameters of both Modified Gravity theories. We compare the two results and constrain the free parameters of both theories on confidence level 1 σ. We can obtain the more accurate results for determining the limits of free parameters of both theories.
Absorber performation of CdTe/CdTe:Cu thins films based from crystal phase and microstructures
Authors: Putra N M D , Sugianto  , Astuti B , Marwoto P 
Published: November 2019

Abstract
It has been successfully grown thin film CdTe, CdTe:Cu (2%) and CdTe:Cu (15%) using DC Magnetron Sputtering method. Sample preparation was performed with different temperature and plasma power parameters above the ITO (Indium Tin Oxide) substrates. Then sample a thin film on annealing for 20 minutes. The addition of Cu doping causes the film polycrystalline structure to change from zincblende (cubic) to wurtzite (hexagonal) crystal phase. The optical transformation of CdTe as absorber is indicated parameter by the Eg = 1.48 eV or α = 7,348×104 cm−1 corresponding to the CdTe:Cu (2%) thin film sample with optimum crystal size and high lattice parameters.
Preliminary study of great earthquakes relocation in the last decade (2008-2018) in north and central region of Sulawesi Island
Authors: Huda A M M , Ridlo N K E L 
Published: November 2019

Abstract
Research has been conducted to determine the position of earthquakes that occurred in Sulawesi Island in the last decade (2008-2018). The study area included 2.64 N; 126 E; 118.57 W; and -7.36 S with a maximum depth of 1000 km. A total of 13 data of seismicity were recorded on 26 BMKG stations with a magnitude more than equal to 6 Richter scale. Relocation was done based on the travel time data of P wave and S wave obtained from the Seismic Analysis Code. The data were processed using Geiger method to determine earthquake position. The earth model used in this study was diverse. The relocation result depends on the model of the earth used. Local earth models were required to perform routine data analysis of activities in the region of Sulawesi earthquake.
Influence of annealing time on the morphology and oxygen content of ZnO:Ga thin films
Authors: Marwoto P , Khanifah L , Sulhadi  , Sugianto  , Astuti B , Wibowo E 
Published: November 2019

Abstract
The effect of annealing time on the morphology and oxygen content of ZnO:Ga films has been deeply studied. ZnO:Ga films were grown with the use of the dc Magnetron Sputtering on the corning glass substrate. The films are grown with a plasma power of 30 watt, Argon gas pressure of 500 mtorr, and a substrate temperature of 300 °C for an hour deposition. The effect of annealing time on the morphology of ZnO:Ga films was observed by using Scanning Electron Microscope (SEM), whereas the oxygen content of the film was determined by Energy Dispersive X-ray (EDX) spectrometers. The SEM images showed that the ZnO:Ga film grown with an annealing time of 40 minutes possess relatively more homogeneous and compact morphology with smoother grain size than the ZnO:Ga films that deposited with annealing times of 30 and 50 minutes. The EDX results confirmed that this film possess lowest oxygen content (24.5 % of mass) but highest Ga content (1.7 % of mass) comparated to the ZnO:Ga thin films grown with another annealing times.
Characterization of mahogany leaf litter (Swietenia macrophylla King) as a raw material of decay resistance biocomposite
Authors: Aryani N P , Fibriana F , Anwar A F , Ummayah F F D , Alighiri D , Harjono  , Masturi  
Published: November 2019

Abstract
Leaf litter is an organic waste that can be degraded biologically in nature. Based on the previous research, mahogany trees in Universitas Negeri Semarang (UNNES) campus produce about 10 ton ha−1 leaf litter in campus forest area and 2.5 ton ha−1 along campus street within three-month-period. By this abundant amount of leaf litter, it is quite difficult to overcome the problem of litter management. Therefore, the idea of leaf litter utilization as a raw material of biocomposite is promising to reduce the use of wood as an important commodity of human needs. However, the characterization of leaf litter feasibility for biocomposite production has not been done. This research aims to characterize the physicochemical properties of mahogany leaf litter. Leaf litter was oven-dried for 5 h at 50 °C and then was ground using a mechanical blender to obtain leaf litter powder. Then, the proximate (moisture, proteins, fat and carbohydrate content) and Fourier transform infrared spectroscopy (FTIR) analysis were performed. The results show that the content of crude ash is 9.90 ± 0.65%; crude protein content 24.83 ± 0.79%; crude fat content 11.37 ± 1.05%; volatile compound 65.14 ± 4.77%; charcoal content 7.66 ± 0.71%; and moisture content 6.61 ± 0.69%. The FTIR spectrum shows that leaf litter has low water content and indicates the content of phenolic compounds such as flavonoid. The physic-chemical properties of mahogany leaf litter indicate that mahogany leaf litter is suitable to be used as the decay resistance of biocomposite material.
Processing of recycled waste PET (polyethylene terephthalate) plastics bottle into for the lightweight and reinforcement bricks
Authors: Alighiri D , Yasin M N , Rohmawati B , Drastisianti A 
Published: November 2019

Abstract
PET (polyethylene terephthalate) waste is a plastic bottle waste that difficult to recycle in large scale, so it was causing environmental pollution. In this research, PET waste used as a main material of bricks by using the mix design method. The mix design method used includes cutting of PET waste, melting of PET waste, mixing with other materials, and molding the materials. This research used four variations of PET waste added by cement and sand to find the ideal composition that mentioned by SNI (Indonesia National Standard). The ideal composition of brick is solid plastic: cement: sand volume ratio is 66:22:12. The result of this research showed that brick quality is ideal, which was characterized by FT-IR and SEM. This composition has 0% of water absorbency, the compressive strength is 75 Kg/cm2, water absorbency of SNI brick is under 20%, and the compressive strength is between 60-100 Kg/cm2.
Exploration of confidence in research skill for pre-service physics teacher
Authors: Yanti F A , Kuswanto H , Mundilarto  , Nasir  , Habibi  
Published: November 2019

AbstractTeacher is the main actor who has important role in problem solving in every learning process. The problem solving can be done through research studies. Uniquely, teachers’ research reports in Indonesia are more done by the male teachers than the female teachers. Teacher comes from a trained pre-service teacher. Research skills are obtained when they become pre-service teachers. This research exploring belief in the research skill of pre-service teacher and showing the difference of research skills based on gender. The method used was through some surveys on a Likert scale. This research skills questionnaire was measuring as follows: planning, choosing problems, studying literatures, choosing instruments, collecting data, choosing method and analyzing data, interpreting data and concluding research result. Samples were chosen from random sampling consists of 22 males and 140 female’s pre-service physics teachers of university in Lampung. The results showed that the average value of different test for each aspect of research skills obtained p-value ≥0.05. The conclusion that pre-service physics teachers have good research skills of average value = 4.03, there is no significant difference by gender. The result of this survey can be used in developing research skills of pre-service teachers, especially in publication of article.
Developing an instrument of scientific literacy assessment to measure natural science teacher candidates in force subject
Authors: Rusilowati A , Yulianto A , Ikhsannudin  , Astuti B , Huda N 
Published: November 2019

Abstract
The aim of this study to develop an instrument of scientific literacy assessment that tested its validity, reliability, characteristics, and described the skills of natural science teacher candidates, consist of three aspects based on PISA 2015 as follow: cognitive, competence, and affective aspect. The subjects are 2nd semester natural science teacher candidates at Universitas Negeri Semarang. Test validity has been done by the content, construct, and concurrent validity. Test reliability has been done by calculating a reliability coefficient “r”. Characteristics tested by determining the level of difficulty and distinguishing features. Profile of scientific literacy skills is determined by measuring natural science teacher candidates’ mastery of scientific literacy. The result of a reliability test is the value of “r” is 0.71 in high category. Validity test results showed that the instrument fulfils the content, construct and the concurrent validity with very valid category and strong validity. The characteristics of developing an instrument assessment showed that the instrument has a level of difficulty that the proportion is 26.7%. The result of distinguish analysis obtained 56.7% of the items with the good quality. Profile of scientific literacy skills showed that the cognitive and competency aspect of natural science teacher candidates is very low and the affective aspect is good.
Science, technology, engineering, and mathematics (STEM) based learning of physics to develop senior high school student’s critical thinking
Authors: Yulianti D , Wiyanto  , Rusilowati A , Nugroho S E , Pangesti K I 
Published: November 2019

AbstractThe purpose of this research is to know the development of senior high school student’s critical thinking skills through Science, Engineering, Technology and Mathematics (STEM) based learning physics. The critical thinking indicators developed in this study include hypothesizing, interpreting, analysing, summarizing and evaluating. Design of this research uses One Group Pretest-Posttest Design. Subjects in this study were 2nd grade of Senior High School Students, from three Senior High School in Semarang City. The results showed that discussion, experiment, project making and presentation activities that were packaged in STEM based physics learning could develop critical thinking skills in aspects of hypothesizing, interpreting, analysing, summarizing and evaluating. The result of the gain test shows the development of hypothesis, analysing, and evaluating ability included in high category, while the ability to interpreting and summarizing is included in the medium category.
Using pine and cocoa waste with pyrolysis technology by liquid smoke, charcoal and bio char
Authors: Wijaya M , Wiharto M , Danial M 
Published: November 2019

AbstractIn this research, the pyrolysis proceeded at five destilate temperature, ie. 115 until 515°C.Targeted results of this study was to use liquid smoke, charcoal, oil, and gas produced from Biomass (Pine wood and Cacao shell) waste through fast pyrolysis technology, so the charcoal can be used potentially as bio fuelleather raw material analysis showed that leather raw material for wood pine analysis showed that the lignin content 26,06%, and so, 49,23% alpha cellulose and hemicelluloses content of 23,62%. and lignin content cacao waste 46,82%, so 26,73% alpha cellulose and hemicelluloses content of 4,86%.GC-MS results showed that liquid smoke each source contains different compounds. Different types of compounds found in liquid smoke from pine waste condensate such as acid (4 types), keton (10), alcohol(1), phenol(1), esters(3), quaiacol(1), aldehyde (1).furfural (1) and so on. And Cacao waste such acid (3 types), keton (7), alcohol (3), Alkana (1), Levoglucosan (1), resorcin (1), and so on. Identification of liquid smoke from the hazelnut shell by GC-MS yield potential chemical components including products levoglucosan and hydroxy methyl furfural as Biofuel and chemical raw material.FTIR analysis results for charcoal pine shell can be seen in Table 1shows. Changes in aromatic peak at 1579 cm− 1shows that it contains lignin. 1159,1cm−1indicated dehydration and depolymerization of cellulose and hemicelluloses content. Wave number3423 cm-1 shows hydroxyl group. FTIR analysis results for charcoal cacao l can be seen Changes in aromatic peak at 1585 cm−shows that it contains lignin. 1111 cm−1indicated dehydration and depolymerization of cellulose and hemicelluloses content The wave number 3406 cm-1 shows hydroxyl group. Pyrolysis technology may reduce carbon emission.Each of the ten challenges was presented with a review of relevant literature followed by future directions which can ultimately lead to technological eco friendly that would facilitate commercialization of pyrolytic biochar.
Titania nanoparticles coated on polycarbonate car headlights for self-cleaning purpose
Authors: Chandren S , Zulfemi N H 
Published: November 2019

Abstract
Due to the quick advancement of automotive headlights from glass to polycarbonate (PC) plastic, ultraviolet (UV) hard coating that offers excellent properties are ideal in meeting the requirements of modern designs. However, PC is known to deteriorate upon exposure to sunlight, moisture, dirt and other environmental conditions. In this work, TiO2 in the form of suspensions were attached on the PC sheet’s surface that had been modified by sodium hydroxide (NaOH) and 3-aminopropyltrimethoxysilane (APTMS). FESEM results showed that the TiO2 are almost spherical in shape and agglomerated. Analysis using GI-XRD showed that the coated samples were of anatase phase with low crystallinity. Based on the results, it was found that TiO2 prepared via method 3 coated on PC sheets managed to produce a more uniform coating, with the strongest adhesion, although with some reduction in transparency. The photocatalytic activity testing was carried out through the photodegradation of methyl orange (MO) under UV light irradiation and it was found that the prepared samples were able to decompose MO, although not at a lower percentage. It can also be observed that PC sheet coated with TiO2 prepared by method 3 showed a higher photocatalytic activity as compared to the other method.
Topical anti-inflammatory activity of n-hexane extract of santalum album linn leaves on rat ear oedema induced by croton oil
Authors: Puspawati N M , Rita W S 
Published: November 2019

Abstract

Santalum album Linn (S.album) has been traditionally used to treat inflammation. This research aimed to evaluate topical anti-inflammatory activity of nhexane extract of S.album leaves on croton-oil induced rat ear oedema. The anti-inflammatory activity test was done using 25 Wistar rats which divided randomly into five groups. Group 1 (negative control, croton oil 35% in acetone only), group 2 (positive control, hydrocortisone drug 2.5% and croton oil), and groups 3, 4, and 5 treated with 10, 20, and 40 mg/ear of n-hexane extracts respectively along with the croton oil. The rat ear-oedema thickness was measured manually using micrometre after 6 hours of observation. The topical application of n-hexane extract of S.album leaf at doses 10 and 20 mg/ear, and hydrocortisone significantly reduced croton-oil induced rat ear oedemawith percentage inhibition of 36, 52, and 73 % respectively. However, at a higher dose of 40 mg/ear, it did not significantly inhibit inflammation as compare to negative control. Histology analysis result also revealed that n hexane extract at doses 10 and 20 mg/ear, and hydrocortisone decreased significantly infiltration of leukocytes. Based on this result, it can be concluded that n-hexane extract of Santalun album Linn leaf showed topical anti-inflammatory activity in a dose dependent manner.
Removal of Cu(II) ions from aqueous solution by fatty hydroxamic acids immobilized onto bentonite
Authors: Suhendra D , Gunawan E R , Asnawati D , Triyatnoko W 
Published: November 2019

Abstract
The mining business in Indonesia has a large contribution to economic growth and the supplies of domestic minerals. However, if the mining businessis conducted illegally and does not use the good mining practice, it will not only harm the country but also risk endangering human safety due to environmental damage caused. In gold mining process, only the main metal, that is gold, is taken while the other metal is discharged into the sewer as waste.One of the metal ions to be waste is copper ion, Cu(II) ion. In this study, removal of Cu(II) ions from illegal gold mining waste was carried out using fatty hydroxamic acids (FHA) immobilized onto bentonite.The FHA used is enzymatically synthesized from Jatropha curcas L. kernel oil. The effects of Cu(II) ion pH and FHA concentration on copper removal have been investigated.The presented results indicated that the extraction of Cu(II) ion was very sensitive to the copper ion pH and extractant concentration. The optimum pH of Cu(II) ion adsorption by FHA-Bentonite (FHA-Bent) is pH 5.A quantitative recovery of Cu(II) ion from FHA-Bent was obtained using 10% HNO3 solutions as eluent with a pre-concentration factorupto 60.