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“Analisis Kadar Besi (Fe) dan Mangan (Mn) Pada Air Baku dan Air Reservoir Menggunakan Metode Kolorimetri di Instalasi Pengolahan Air Minum PDAM Tirtanadi Cabang Delitua
No full textAn analysis of the levels of Iron (Fe) and Manganese (Mn) in raw water and reservoir water has been carried out using the colorimetric method. Determination of levels of iron (fe) and manganese (Mn) aims to determine the quality of raw water and reservoir water at the Drinking Water Treatment Plant of PDAM Tirtanadi Delitua Branch and its feasibility according to the Minister of Health Regulation Number: 492/MENKES/PER/IV/2010. The results of the analysis of the levels of iron (Fe) and manganese (Mn) in raw water and reservoir water are 0.72 mg/L and 0.08 mg/L, respectively, while the manganese (Mn) content is 0.261 mg on average. /L and 0.00575 mg/L. Based on this data, the quality of raw water and reservoir water meets the standards of the Minister of Health Number: 492/MENKES/PER/IV/2019.48 HalamanKertas Karya Diplom
“Analisis Kadar Besi (Fe) dan Mangan (Mn) Pada Air Baku dan Air Reservoir Menggunakan Metode Kolorimetri di Instalasi Pengolahan Air Minum PDAM Tirtanadi Cabang Delitua
No full textAn analysis of the levels of Iron (Fe) and Manganese (Mn) in raw water and reservoir water has been carried out using the colorimetric method. Determination of levels of iron (fe) and manganese (Mn) aims to determine the quality of raw water and reservoir water at the Drinking Water Treatment Plant of PDAM Tirtanadi Delitua Branch and its feasibility according to the Minister of Health Regulation Number: 492/MENKES/PER/IV/2010. The results of the analysis of the levels of iron (Fe) and manganese (Mn) in raw water and reservoir water are 0.72 mg/L and 0.08 mg/L, respectively, while the manganese (Mn) content is 0.261 mg on average. /L and 0.00575 mg/L. Based on this data, the quality of raw water and reservoir water meets the standards of the Minister of Health Number: 492/MENKES/PER/IV/2019.48 HalamanKertas Karya Diplom
Efektifitasnanokomposit Zink Oksida Carbon Dots Sebagaifotokatalis Padafotodegradasi Metilen Biru Dibawahradiasi Sinar UV
No full textIn this study, several stages of work have been carried out, that is the synthesis
of nitrogen doped carbon dots (CDs), nitrogen doped zink oksida (N-ZnO) and N-ZnO
/CDs as photocatalysts in photodegradation of organic pollutants methylene blue
(MB). In the first stage, the synthesis of CDs was carried out using soybean as a
precursor and ethylenediamine as nitrogen doping using the hydrothermal method at a
temperature of 180oC for 8 hours. In the second stage, N-ZnO synthesis was carried
out using urea as a nitrogen dopant with a calcination method at a temperature of 500oC
for 2 hours in air (N2) condition and heating rate of 5
oC/min. The calcination
temperature is determined from the results of the TGA analysis. In the third stage, the
synthesis process of N-ZnO/CDs nanocomposites was carried out using a simple one
method with concentration ratio of 2: 1. The results of this study show that CDs have
been successfully synthesized which is confirmed from the results of HR-TEM, which
shows that CDs are spherical with a particle size of 4,249 nm. Based on the
caharacterization results of XRD and HR-TEM, N-ZnO and N-ZnO/CDs
nanocomposites have a hexagonal wurtzite structure. The materials N-ZnO and N ZnO/CDs nanocomposites also experienced an increase in photocatalyst
characteristics such as adsorption in the visible beam region, having a mikroporous
structure, with a small Eg value of N-ZnO (2.78eV), N-ZnO/CDs (2.45 eV) and
surface area (SBET) N-ZnO (3.827 m2
/g), N-ZnO/CDs (3.757 m2
/g). In the fourth stage
photocatalyst CDs, N-ZnO and N-ZnO/CDs were used in methylene blue
photodegradation under UV B light radiation for 60 min. Photocatalysts of
nanocomposites N-ZnO/CDs showed the highest photodegrading effectivity of 83.4%
with a degradation rate k= 0.0202 min-1
. This is evidenced from UV-Vis and PL data
which explains that N dopant in ZnO forms p-type semiconductors, as well as the
addition of CDs which act as energy transfer and photosensitizers so as to reduce and
prevent electron-hole recombination. From this study, it was concluded that N ZnO/CDs nanocomposites can be an ideal photocatalyst material for the degradation
of methylene blue organic liquid waste.136 HalamanTesis Magiste
Green Synthesis of Barium Doped Titanium Dioxide Using Palm Leaf Extract (Elaeis guineensis Jacq.)
Get PDFConventional synthesis of titanium dioxide (TiO₂) nanoparticles often involves the use of toxic chemicals, high costs, and extreme operating conditions. This research aims to develop a cost-effective and environmentally friendly green synthesis method for TiO₂ by utilizing oil palm leaf (Elaeis guineensis Jacq.) extract as a reducing and stabilizing agent. Subsequently, doping with barium (Ba) was carried out to enhance the photocatalytic, optical, and electrical properties of the resulting TiO₂. Phytochemical analysis revealed that oil palm leaf extract contains alkaloids, flavonoids, terpenoids, saponins, and tannins, which play a role in the reduction and stabilization processes of TiO₂ nanoparticles. Characterization using Fourier Transform Infrared Spectroscopy (FTIR) identified Ti-O bonds in pure TiO₂ at a wavenumber of 588 cm⁻¹, and a shift in absorption peaks in the range of 548-595 cm⁻¹ in Ba-doped TiO₂ indicated the formation of the barium titanate phase. X-ray Diffraction (XRD) analysis showed that Ba doping increased the crystallite size of TiO₂ from 1.17 nm to 1.65 nm, which may have implications for photocatalytic applications
Functionalization Mesoporous Silica using Aminopropyltriethoxysilane (APTES) as Adsorbent for Removal Ni (II) from Aqueous Solution
Get PDFThis study successfully synthesized mesoporous silica using the template methyl ester ricinoleate (MS-TMR) and further functionalized the MS-TMR surface with 3-aminopropyltriethoxysilane (APTES). The functionalization of MS-TMR with APTES was achieved through a 48-hour grafting method. For the adsorption experiments, 20 mg of both MS-TMR and MS-TMR-APTES adsorbents were employed to remove Ni(II) from aqueous solutions at a concentration of 30 mg/L and pH 6. The objective was to assess the adsorption capacity and to characterize the synthesized adsorbents. Characterization was conducted using Fourier Transform Infrared Spectroscopy (FTIR) and X-ray Diffraction (XRD). FTIR analysis revealed that the MS-TMR adsorbent possessed silanol (Si-OH) and siloxane (Si-O-Si) groups. Conversely, the MS-TMR-APTES adsorbent exhibited additional amine (N-H) and C-H groups after the APTES grafting. XRD results indicated that both samples were amorphous. The concentration of Ni(II) ions was determined using Atomic Absorption Spectroscopy (AAS), which facilitated the calculation of removal percentages and adsorption capacities. MS-TMR achieved a mere 3.54% removal of Ni(II) ions, corresponding to an adsorption capacity of 3.21 mg/g. In contrast, MS-TMR-APTES demonstrated significantly enhanced performance, removing 54.23% of Ni(II) ions with an adsorption capacity of 48.81 mg/g. The findings suggest that APTES-functionalized MS-TMR has considerable potential for removing Ni(II) ions and could be explored further for the adsorption of other heavy metal ions
Validation Method of 3,4-Methylenedioxymethamphetamine (MDMA) Analysis Using Gas Chromatography Mass Spectroscopy
Get PDFMDMA is known as a narcotic and stimulant is a drug that is often abused, both in pill and powder form. Therefore, it is important to have an accurate and sensitive analysis method to detect the presence of MDMA especially in urine samples of drug users. In this work, optimization of the GC-MS method was carried out to obtain the best separation conditions and the highest sensitivity using the GCMS instrument. This study aims to develop a validation method for the analysis of 3,4-methylenedioxymethamphetamine (MDMA) using the Gas Chromatography-Mass Spectrometry (GCMS) technique. The results of the analysis showed that the accuracy, precision, linearity, limit of detection, limit of quantification and selectivity were respectively: 97.53%, 3.66%, R² ≥ 0.99, LOD 0.7 ppm, LOQ 2.35 ppm, and Rs 19.83. The results of the study showed that this method has good accuracy with acceptable precision values and low enough LOD and LOQ to detect MDMA at appropriate concentrations. Thus, this validated GC-MS method can be effectively applied for the analysis of MDMA in various urine sample matrices, especially in the development of the field of analytical chemistry
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
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