65 research outputs found
Compound-specific isotope analysis of diesel fuels in a forensic investigation
Compound-specific isotope analysis (CSIA) offers great potential as a tool to provide chemical evidence in a forensic investigation. Many attempts to trace environmental oil spills were successful where isotopic values were particularly distinct. However, difficulties arise when a large data set is analyzed and the isotopic differences between samples are subtle. In the present study, discrimination of diesel oils involved in a diesel theft case was carried out to infer the relatedness of the samples to potential source samples. This discriminatory analysis used a suite of hydrocarbon diagnostic indices, alkanes, to generate carbon and hydrogen isotopic data of the compositions of the compounds which were then processed using multivariate statistical analyses to infer the relatedness of the data set. The results from this analysis were put into context by comparing the data with the Ī“13C and Ī“2H of alkanes in commercial diesel samples obtained from various locations in the South Island of New Zealand. Based on the isotopic character of the alkanes, it is suggested that diesel fuels involved in the diesel theft case were distinguishable. This manuscript shows that CSIA when used in tandem with multivariate statistical analysis provide a defensible means to differentiate and source-apportion qualitatively similar oils at the molecular level. This approach was able to overcome confounding challenges posed by the near single-point source of origin, i.e., the very subtle differences in isotopic values between the samples
The Untruth Friendship and Starvation in Milneās Winnie-the-Pooh
This research aims to explore (1) the untruth friendship of Winnie-the-Pooh and (2) its advice for solving starvation of human being in Milneās Winnie-the-Pooh. The research is a descriptive qualitative method with the support of semiotic approach. It uses smoke-fire concept in Pierceās Index to look after Aristotleās 8 characteristics of friendship. Those are explored through Winnie-the-Pooh novel as a primary data and Nicomachean Ethics, book of sociology, and dictionaries as a secondary data. The research discover the untruth is over 4 acts of characters. It keeps some friendship characteristics within. Therefore, those 4 acts directs a man to get a help of a friend
Forensic differentiation of diesel fuels using hydrocarbon isotope fingerprints
Abstract
Compound-specific isotope analysis (CSIA) is fast becoming an important tool to provide chemical evidence in a forensic investigation. Attempts to trace environmental oil spills were successful where isotopic values were particularly distinct. However, difficulties arise when a large dataset is analyzed and the isotopic differences between samples are subtle. Thus, this study intends to demonstrate any linkages between diesel fuels in a large number of datasets where subtlety in the isotopic values is accentuated by the near single-point source of origin. Diesel fuels were obtained from various locations in the South Island of New Zealand. Aliquots of these samples were diluted with n-pentane and subsequently analyzed with gas chromatography-isotope ratio mass spectrometry (GC-IRMS) for carbon and hydrogen isotope values. The data obtained were subjected to principal component analysis (PCA) and hierarchical clustering. A wide range of Ī“13C and Ī“2H values were determined for the ubiquitous alkane compounds (the greatest values being ā4.5ā° and ā40ā°, respectively). Based on the isotopic character of the alkanes it is suggested that diesel fuels from different locations were distinguishable and that the key components in the differentiation are the Ī“2H values of the shorter chain-length alkanes. However, while the stable isotope measurements may provide information to classify a sample at a broad scale, much more detailed information is required on the temporal and spatial variability of diesel compositions. The subtle differences of the stable isotope values within the alkanes of different diesel fuels highlighted the power of CSIA as a means of differentiating petroleum products of different origins, even more so when two or more stable isotopes data are combined. This paper shows that CSIA when used in tandem with multivariate statistical methods can provide suitable tools for source apportionment of hydrocarbons by demonstrating a straightforward approach, thus eliminating lengthy analytical processes
Evaluasi Kebijakan Penggabungan Sekolah Dasar Negeri Kota Pekalongan Tahun 2013
Based on the data about Elementary School in Pekalongan City was discovered some problems up until now been homework for the Goverment of Pekalongan City especially the problems of infrastructure and facilities, teachers, and equitable access to quality education. Because of those problems, the Goverment of Pekalongan City in 2013 made policies that aim to create Elementary school that is effective and efficient based on the decision of Pekalongan Mayor number 421.2 / 151/2013 aboutpoliciesin combining elementary schools in Pekalongan city environment which is done in two ways: CombiningElementary school based on a pure region conducted in 40 schools that produced 16 State Elementary School and 16 principals and combining elementary school by one management conducted in 46 of state elementary schools and produced 23 principals and 46 elementary schools.The approach used in this research is descriptive qualitative with data collection methods such as observation , documentation and interview. The research subjects were Office of Education, Youth and Sports (Dinas Pendidikan Pemuda dan Olahraga)Pekalongan and all of the State Elementary School as the policies result combining a State Elementary School policies in Pekalongan with the unit of analysis of four elementary schools as a result of the combinationby pure region and four elementary schools based on the result of combining the management of four different sub-districts.The evaluation result of policies shows the difference between input that was given by a combination school based on management with combination school based on pure region. This difference makes a combination schoolby pure region is more effective and efficient, whereas the effectiveness combination school by management hasn't yet been reached maximum. Moreover, this policy is not participatory but top down that means there's no involvement of implementing policy in the policy formulation process.This research recommend that the need of the re-assesment about combination school based on management because this policy has not been proved able to answer the the problems of education in Pekalongan City, meanwhile for the policy about combination school based on pure region was already good enough in realizing an effective and efficient education in Pekalongan City
Work Ethic of Muslim Traders in Palakka Central Market, Bone Regency and its Effect on Increasing Economic Welfare
A high work ethic is needed in completing a job. The problem is studied in this study to see the work ethic of Muslim traders in running their business and its effect on improving their welfare. There are approximately 450 traders in the Central Market. The research method used in this research is to use a quantitative approach. The data collection techniques used in this study were using a questionnaire, interview, and documentation. The data analysis used is descriptive statistical analysis and inferential statistical analysis. The ability of the independent variable to explain the variance of the dependent variable is 56 percent. This means that there is 44 percent (100 percent - 56 percent) of the variance of the dependent variable which is explained by other factors. This means that the work ethic variable has an effect of 56.0% on the improvement of the economic welfare of Muslim traders in Palakka Market, Bone Distric
KANDUNGAN KIMIA DAN DIMENSI SERAT AKAR, CABANG DAN BATANG BAGIAN ATAS KAYU GMELINA DAN KAYU JATI DI HUTAN RAKYAT SULAWESI SELATAN
The wood species used in this research was gmelina wood from community forest, Maros Regency and jati wood from community forest, Barru Regency. For objective of the research, parts of the tree were taken a short cut (5 cm) from root, branch and top of the tree. All samples were tested their chemical component (cellulose, hemicellulose, lignin and extractives) and fiber dimensions with itās derivates fiber. The results showed that root, branch and top of the tree of gmelina wood and jati wood from community forest can be used as a raw material for pulp and papers.
Key words: Chemical content, Fiber Dimension, Gmelina Wood, Jati Wood, Community Fores
MFCS 2 IN 1 : MICROBIAL FUEL CELLS PENGOLAH AIR LIMBAH DAN PENGHASIL LISTRIK (ALTERNATIF : LIMBAH ISI RUMEN SAPI DENGAN PENGARUH VARIASI COD DAN PH)
Seiring dengan meningkatnya pertumbuhan populasi penduduk, konsumsi masyarakat akan pangan pun meningkat. Salah satu kebutuhan akan protein hewani dari daging sapi. Di kota Semarang frekuensi pemotongan hewan sekitar 40-50 ekor sapi dan meningkat hingga 100 ekor sapi perhari menjelang lebaran (Suaramerdeka, 2012). Frekuensi pemotongan yang tinggi ini berpotensi untuk menimbulkan limbah. Limbah yang berasal dari rumen sapi fasa cair mengandung konsentrasi COD sebesar 5.500-7000 mg/L (Padmono, 2005). Oleh karena itu perlu dilakukan pengolahan sebelum dibuang ke badan air penerima. Reaktor terbaru dari proses pengolahan anerobik yang sering digunakan dalam pengolahan air limbah yang saat ini telah banyak dikembangkan yaitu microbial fuel cells. Menurut (Aeltermn et al. 2006 dalam Zhang, 2012) microbial fuel cells (MFCs) adalah reaktor bioelektrochemical yang dapat mengkonversi energi kimia dari zat organik pada air limbah menjadi listrik dengan katalis dari mikroorganisme. Penelitian dengan MFCs dual chamber dengan substrat limbah rumen sapi fasa cair dengan variasi pH 7 (netral), pH 5 (asam), pH 9 (basa) ini menunjukan bahwa variasi pH berpengaruh terhadap penurunan konsentrasi COD dan produksi listrik pada pengolahan air limbah rumen sapi menggunakan reaktor Microbial fuel cells. Rreaktor dengan varioasi pH netral produksi listrik terbesar adalah 219,0916 mW/m2, sedangkan variasi pH asam dan pH basa power density terbesar 108,5341 mW/m2 dan 174,5589mW/m2 . Penurunan COD optimum pada hari ke 10 untuk pH netral COD 167,5 mg/L pada reaktor N1 (memenuhi baku mutu), pH asam COD 185,2 mg/L pada reaktor A2 (memenuhi baku mutu), dan pH basa 292,1 mg/L (belum memenuhi baku mutu). Efisensi penyisihan optimum pada pH netral 94,8%, pH asam 94,4% dan pH basa 88,1 %. Pada reaktor dengan variasi substrat pH netral power density, penurunan COD dan efisiensi penurunan lebih baik dibanding dengan pH asam dan basa, meskipun demikian mikroorganisme dalam limbah rumen sapi tetap dapat berkembang biak dalam kondisi substrat pH ekstrim.
Kata Kunci : MFCs, limbah rumen sapi, pH, power density, CO
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