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"Karakterisasi Bentonit-Cr dan Zeolit komersial HZSM-5 sebagai katalis padaproses konversi ethanol menjadi biogasolin. Bentonit-Cr memiliki sifat keasamanyang tinggi serta tahan terhadap kandungan air yang banyak, sehingga selainmampu memproses umpan yang mengandung kadar air yang cukup besar daricampuran ethanol-air, juga mempunyai umur katalis yang panjang. Bentonit-Cryang kemudian digunakan sebagai material katalis yang hasilnya akandibandingkan dengan Zeolit HZSM-5, serta dilakukan karakterisasi kedua katalistersebut dengan XRD, SEM, BET, TGA, Catalytic Muffler, dan GC-MS. Darihasil analisa tingkat keasaman dengan menggunakan metode gravimetri dapatdiketahui bahwa tingkat keasaman dari Bentonit-Cr yang paling tinggi dan jugadari hasil XRD dapat diketahui adanya pergeseran sudut 2theta pada Bentonit-Cr,hal tersebut mengindikasikan bahwa proses pilarisasi berhasil dilakukan, sertadidukung dengan data BET yang menunjukkan bahwa adanya penambahan luaspermukaan spesifik pada Bentonit-Cr dibandingkan dengan bentonit yang belumdipilarisasi. Selanjutnya dilakukan uji aktivitas katalis dan hasil yang didapatkandiuji dengan GC-MS. Dari Hasil GC-MS dapat diketahui ethanol telah berubahmenjadi Butanol dan kemungkinan terbentuk Hexanol, Decane, Undecane, sertaDodecane. Kesemua senyawa tersebut dalam range gasolin yaitu C4 sampaidengan C12.

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Abstract Characterization of Bentonit-Cr and commercial Zeolit HZSM-5 as catalysts forethanol conversion to biogasoline. Bentonit-Cr has high acidity and resistant to alot of moisture, so in addition to being able processing feedback which a lot ofmoisture from the concentration of ethanol-water mixture, also it?s not easydeactivated. Bentonit-Cr which is used as catalyst material for ethanol conversionto biogasoline and the result will be compared using Zeolit catalyst HZSM-5 andperformed characterization of both catalyst with XRD, BET, TGA, CatalyticMuffler, and GC-MS. The result of this acidity test using gravimetric method areshown in acidity level of Bentonit-Cr is the highest and also the result of XRDtesting are known that shift angle 2theta on Bentonit-Cr, it?s indication that Crelement on the Bentonit can interaction, and those supported by BET data areshown that the addition of specific surface area in Bentonit-Cr compared withBentonit which not pillared yet. As for the ETG testing results analyzed by GCMS,there has been conversion of ethanol into biogasoline, in which butanol andpossibly also hexanol, decane, dodecane, undecane were form. Those compoundsare included in the gasoline range C4 until C12."

"Background: Esophagitis implies an organic damage of the esophagus due to several pathophysiologic factors, predominantly: (1) degree of gastric acid secretion (gastric pH), whereabouts are rapidly or slowly to be mucosal breaks onto esophagus were under the influe nced by: (a) gastric pH 54 and (b) the contact of gastric acid into esophageal mucosal. (2) Lower esophageal sphincter (LES) as a important lactor lor antifetlux mechanisms, which antireflux mechanism cannot senre as a barrier system whenever tone of LES comes down until 510 mml-lg that causes feeble resting LES pressure. Esophageal injuries are recognized endoscopicaliy by the presence of the Savary-Millers classification (1985), but there are not definitely which ones principally to pathophysiologic factor. Methods: This was a consecutive non-random sampling cross sectional study Thirty subject from 127 patients with dyspepsia undergoing elective upper-endoscopic examination with collecting of the gastric juice and biopsies of tower esophageal mucosal, also esophageal manometric examination. Before that, clinical inclusive and exclusive criterias until laboratory examination were performed. Significant interval was 95%. Analyzing data with Fisher?s Exact Test One-Tail to correlate between gastric pH and hypotonic LES into esophagitis. Results: Esophagilis prevalence was 22. 8%. Fisher's Exact Test One-Tail to correlate esophagitis with gastric pH E 4 was significant (p=0.013798), but with hypotonic LES (tones of LES S 10 mmHg) was not (p=0.60269). The combined roles or' gastric pH and tones of LES into esophagitis are included: (1) Frequency of roles of pH E 4 and hypotonic LES are 48.2% (2) Frequency of role of pH < 4 without hypotonic of LES are 33.3%. (3) Frequency of role of hypotonic LES without pH S4 are 11. 1% and (4) Frequency of esophagitis without roles of pH $4 and hypotonic ol LES are 7.4%. Conclusions: The sum of gastric pH 5 4 and hypotonic of LES together are more than each separate factor. Onto statistically was significant between esophagitis and gastric pH, but there is no correlation with tones ol LES. So, gastric pH plays a more important role than LES."

"Tesis ini membahas kadar antioksidan dan tingkat keasaman pada kopi arabika, kopi luwak dan kopi hasil iradiasi BATAN. Penelitian menggunakan sampel kopi yang belum diiradiasi (0 kGy) dan sudah diiradiasi dengan dosis 2,5 kGy; 5 kGy dan 10 kGy. Penentuan kadar antioksidan menggunakan metode DPPH (2,2- diphenyl-1-picrylhydrazil) dengan perangkat spektrofotometer UV-Vis dan penentuan tingkat keasaman menggunakan pH meter. Penentuan gugus fungsi menggunakan FTIR dan penentuan jumlah partikel menggunakan ESR Spectrometer. Hasil kadar antioksidan pada kopi sebelum dan sesudah iradiasi ditentukan dengan nilai persen penghambatan (IC50). Nilai IC50 kopi arabika (Toraja) dengan dosis 0 kGy; 2,5 kGy; 5 kGy dan 10 kGy adalah 54,150 μg/ml (tinggi); 50,326 μg/ml (tinggi); 49,026 μg/ml (sangat tinggi) dan 46,546 (sangat tinggi) dan nilai IC50 kopi luwak dengan dengan dosis 0 kGy; 2,5 kGy; 5 kGy dan 10 kGy adalah 64,226 μg/ml (tinggi); 55,090 μg/ml (tinggi); 58,885 μg/ml (tinggi) dan 56,739 μg/ml (tinggi). Dari pengukuran didapatkan bahwa kopi hasil iradiasi menghasilkan kadar antioksidan meningkat setelah di iradiasi tetapi untuk tingkat keasaman tidak signifikan.

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This thesis discusses the antioxidant and the acidity levels on coffee arabica, civet coffee, and irradiation coffee by National Nuclear Energy Agency (BATAN). This research utilized the sample of coffee before and after irradiation with the varieties of doses (2,5 kGy; 5 kGy and 10 kGy). In the experiment determining the levels of antioxidants using DPPH method (2,2-diphenyl-1-picrylhydrazil) with spectrophotometer UV-Vis and the acidity using pH meter. Determining the cluster functional using FTIR and the number of particles using ESR Spectrometer. Results antioxidant levels on arabica coffee and civet coffee before and after irradiation are shown with IC50 values. IC50 values on arabica coffee (Toraja) with the varieties of dose (0 kGy; 2,5 kGy; 5 kGy and 10 kGy) are 54.150 μg/ml (high); 50.326 μg/ml (high); 49.026 μg/ml (very high) dan 46.546 (very high) as well as IC50 values on civet coffee (Gayo) are 64.226 μg/ml (high); 55.090 μg/ml (high); 58.885 μg/ml (high) dan 56.739 μg/ml (high). From the measurement results showed that the antioxidant levels increased after irradiation but for the level of acidity is not significance."

"ABSTRAKDengan semakin berkembangnya metode soil improvement, khususnya denganmenggunakan Prefabricated Vertical Drain (PVD), maka diperlukan perhatiankhusus dalam menganalisa PVD. Pada umumnya kecepatan waktu konsolidasidipengaruhi oleh jarak dan panjang PVD. Analisa yang digunakan biasanyamenggunakan model konsolidasi 1 dimensi. Seiring perkembangan teknologikomputansi, perhitungan PVD dapat dilakukan dengan metode elemen hingga 3dimensi. Model 3 dimensi memiliki keakuratan yang baik namun tingkatkompleksitas yang lebih tinggi. Perhitungan PVD pada umumnya menggunakanmodel 2 dimensi / plane strain model. Agar model 2 dimensi memiliki keakuratanyang baik diperlukan ekivalensi permeabilitas tanah asli dan jarak PVD. Penulismenitikberatkan kedua hal tersebut dengan harapan diperoleh model yang tepatdalam perhitungan PVD sesuai dengan kenyataan di lapangan

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ABSTRACTWith the development of the soil improvement method, especially usingprefabricated vertical drain (PVD) it is necessary to analyize accurately. Generallythe rate of consolidation time depends on two factor, spacing and the length ofPVD. One dimension consolidation calculation is often used to analyze PVD.With development in computation technology, PVD calculation can be done byfinite element method three dimension which has good accuration but morecomplex. In fact, two dimension model used to calculate PVD in order to havegood accuration the permeability of soil and the spacing of PVD must beequivalent with three dimension model. Thw writer will focus in these factors inhopes to obtain the right PVD calculation model accordance with the fact in field;"