1,428 research outputs found

    Purifikasi Biogas Dengan Variasi Ukuran Dan Massa Zeolit Terhadap Kandungan CH4 Dan CO2

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    Nowadays, the development of the renewable energy very rapidly. It is driven by the nature of the renewable energy that has been proven to be cleaner than conventional energy, so an increase in the use of renewable energy continues to rise. Biogas is produced from biological processes (anaerobic digester) is capable of producing gas such as CH 4 , CO 2 , H 2 S, and other gases. Therefore it is very important to make the process of refining the biogas. In this research, using the biogas purification process purification method stratified, with a solution of sodium hydroxide with zeolite is purified again and again purified with activated charcoal, hence the storied purification. In this study focused on the observation of zeolite as an adsorbent, the size of the fine and coarse zeolite, and zeolite are varied mass of 50 grams, 100 grams and 150 grams. In 60 minutes, the best result obtained on zeolites fine size with a mass of 150 grams of CO 2 obtained down to 4.07%, but the pressure dropped to 0.65 kPa. With the size of the coarse zeolite at 4.26% CO 2 , with a pressure drop of 0.84 kPa. After the purification process, zeolite proved to be hidrofill with the content of the zeolite fine biggest water with 5.4%

    Finiteness in N=1 SYM Theories

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    I present a criterion for all-order finiteness in N=1 SYM theories. Three applications are given; they yield all-order finite N=1 SYM models with global symmetries of the superpotential.Comment: 3 pages, plain LaTex, no figure

    Geometrical Effects in Determination of Fickian Mass Diffusivity of Polymers

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    Hydrophilicity of polymers makes them prone to moisture absorption that leads to degradation of mechanical properties. Kinetics of moisture ingress needs to be fully characterized to perform reliable designs with polymeric materials. The rate of diffusion is the essential parameter in determining the time scale of the moisture uptake in polymeric materials. The model from which the diffusion coefficient is to be determined can be mathematically complex when the viscoelastic relaxation and diffusion time scales are comparable (i.e. Deborah Number ~ l). However, Fickian type of diffusion is shown to be adequate in modeling the moisture absorption into a broad range of polymers. Most methods for determining the diffusion coefficient are based on the solution of Fick's second law in semi-infinite and slab domains from which, a closed form solution has been adapted by the American Society of Testing and Materials (ASTM). However, those techniques either do not consider the errors due to finite sample dimension or the correction factors provided are not precise enough. In addition, fabrication of samples conforming ASTM standard (i.e. length or width to thickness ratio of 100 or greater) may not be practical due to difficulties in producing and testing very thin coupons. In this study, the solution of the Fickian diffusion equation for a three-dimensional rectangular domain is utilized to generate mass gain data for geometries with length to thickness ratios ranging from l to I 00. These data are then used to demonstrate the errors introduced by the two conventional methods used to determine the diffusion coefficient for sample dimensions deviating from an infinitely wide slab. After applying the correction factor suggested by ASTM, up to 13% error is observed in the diffusion coefficient. In order to improve the prediction of diffusion coefficient, a least square curve fit method, which yields accurate predictions regardless of the sample geometry, is proposed.YesPeer reviewed and presented at the 23rd Oklahoma AIAA/ASME Symposium

    New N=2 Superconformal Field Theories in Four Dimensions

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    New examples of N=2 supersymmetric conformal field theories are found as fixed points of SU(2) N=2 supersymmetric QCD. Relations among the scaling dimensions of their relevant chiral operators, global symmetries, and Higgs branches are understood in terms of the general structure of relevant deformations of non-trivial N=2 conformal field theories. The spectrum of scaling dimensions found are all those compatible with relevant deformations of a y^2 = x^3 singular curve.Comment: 17 pages, harvma

    Faktor- Faktor Yang Mempengaruhi Pertumbuhan Kendaraan Bermotor Roda Dua Di Kota Pekanbaru

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    This study aims to determine the factors that influence the growth of two-wheel motor vehicles in the city of Pekanbaru. Data used in this study was a secondary character time series from 2005 to 2014, taking quarterly data. This research uses quantitative study using multiple linear regression analysis with significance level of 5% (0.05), which was applied to the computer program SPSS version 18.0. in this study performed statistical tests (t-test and test-f), the partial correlation coefficient and multiple determination coefficient test. The results showed that together simultaneously (Test F) population, income per capita, and the number of motor vehicle tax on the growth of two wheel motor vehicles amounted to 4.788 with a significance level of 0.049 and partially (t test) each also affect the growth of two-wheel motor vehicles with the results of the equation Y = -2,882,382.778 + 1.926 X1 + 0.259 X2 - X3 7.8054 affect a population of 2,763 with a significance of 0.047, per capita income effect on the growth of two-wheel motor vehicles amounted to 2,573 with significance 0.016 and the number of motor vehicle tax effect on the growth of two-wheel motor vehicles amounted to 0,260 -1.244 with significance. Predictive ability of the two variables are the number of two-wheeled motor vehicle growth was 70.5% (R2 = 0.705), as shown to us by the magnitude of adjusted R2, while the remaining 29.5% is influenced byother variables not included in this study

    Splenic artery angiography: clinical classification of origin and branching variations of splenic artery by multi-detector computed tomography angiography method

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    Background: The splenic artery (SA) variations are rarely reported in the literature. Knowledge of the range of the SA and other arterial anomalies and their specific frequencies is very important ever for every visceral surgeon as well as for treatment of gastrointestinal bleeding, organ transplantation, transarterial chemoembolisation of neoplasm, infusion therapy, therapeutic arterial ligation, iatrogenic injuries. At the literature, there are more studies on the coeliac trunk, superior mesenteric artery and hepatic artery variations, but studies on the SA variations are uncommon. The studies on the SA variations are mostly in the form of case reports, but there are not many studies with large population on this issue. The purpose of this study was to evaluate the SA alone and to determine the variations determined separately from the other arteries. Accurate awareness of all the possible anatomic variations is crucial in the upper abdomen surgery. Materials and methods: Seven hundred fifty patients undergoing multi-detector computed tomography angiography between 2015 and 2017 were retrospectively evaluated for the SA variations. We created a new classification system to determine anatomic variations of the SA. Results: Twenty-three different types were identified related to anatomic variations in the origin and branching pattern of the SA. While 596 (79.47%) patients had standard SA anatomy, 154 (20.53%) patients had variant SA anatomy. Conclusions: The SA has quite different variation types and the practical context of the issue is of primary importance in surgery, gastroenterology, oncology and radiology. Liver and pancreas transplantation, splenectomy, embolisation of tumours of the abdominal organs, as well as other numerous diagnostic and therapeutic procedures, require detailed anatomical knowledg

    The cell biologist's guide to super-resolution microscopy

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    Fluorescence microscopy has become a ubiquitous method to observe the location of specific molecular components within cells. However, the resolution of light microscopy is limited by the laws of diffraction to a few hundred nanometers, blurring most cellular details. Over the last two decades, several techniques – grouped under the ‘super-resolution microscopy’ moniker – have been designed to bypass this limitation, revealing the cellular organization down to the nanoscale. The number and variety of these techniques have steadily increased, to the point that it has become difficult for cell biologists and seasoned microscopists alike to identify the specific technique best suited to their needs. Available techniques include image processing strategies that generate super-resolved images, optical imaging schemes that overcome the diffraction limit and sample manipulations that expand the size of the biological sample. In this Cell Science at a Glance article and the accompanying poster, we provide key pointers to help users navigate through the various super-resolution methods by briefly summarizing the principles behind each technique, highlighting both critical strengths and weaknesses, as well as providing example images

    Nehari manifold and existence of positive solutions to a class of quasilinear problema,

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    Abstract In this paper, existence and multiplicity results to the following nonlinear elliptic equatio

    Trio a novel bovine high-fecundity allele: II. Hormonal profile and follicular dynamics underlying the high ovulation rate

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    The newly discovered Trio high-fecundity allele produces multiple ovulations in cattle. This study evaluated (1) size and growth rates of follicles in Trio carriers during a synchronized follicular wave, induced by follicle aspiration; (2) follicle-stimulating hormone (FSH) patterns associated with the follicular wave; (3) size of corpora lutea (CL) and circulating progesterone; and (4) intrafollicular estradiol concentrations prior to normal deviation. Trio carriers had mean dominant follicles that were significantly smaller in diameter and volume than noncarriers. Onset of diameter deviation occurred at ∼3 days after the last follicle aspiration in both genotypes despite Trio carriers having much smaller individual follicles. Follicles of Trio carriers grew at a slower rate than noncarrier follicles (∼65% in mm/day or ∼30% in mm3/day) resulting in much smaller individual dominant follicles (∼25% volume). However, total dominant follicle volume, calculated as the sum of all dominant follicles in each animal, was similar in carriers and noncarriers of Trio throughout the entire follicular wave. Circulating FSH was greater in Trio carriers during the 24 h encompassing deviation. Trio carriers had significantly more ovulations than noncarriers, and individual CL volume was smaller, although total luteal tissue volume and circulating P4 were not different. Thus, increased ovulation rate in Trio carriers relates to smaller individual follicles (one-third the volume) near the time of deviation due to slower follicle growth rate, although time of deviation is similar, with increased circulating FSH near deviation leading to selection of multiple dominant follicles in Trio carriers with similar total follicle volume

    Proteomic analysis of follicular fluid in carriers and non-carriers of the Trio allele for high ovulation rate in cattle

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    This study was conducted to characterise differences in follicular fluid proteins between carriers and non-carriers of a bovine allele for high ovulation rate. A total of four non-carrier and five carrier females were used in an initial study with four and six additional non-carriers and carriers respectively used in a validation study. Emergence of the follicular wave was synchronised and the ovaries containing the dominant follicle(s) were extracted by ovariectomy for follicular fluid collection. A hexapeptide ligand library was used to overcome the masking effect of high-abundance proteins and to increase detection of low-abundance proteins in tandem mass spectrometry. After correcting for multiple comparisons, only two proteins, glia-derived nexin precursor (SERPINE2) and inhibin β B chain precursor (INHBB), were significantly differentially expressed (false-discovery rate <0.05). In a replicate study of analogous design differential expression was confirmed (P<0.05). Joint analysis of results from the two studies indicated that three additional proteins were consistently differentially expressed between genotypes. For three of these five, previous studies have indicated that expression is increased by transforming growth factor-β-bone morphogenetic protein signalling; their reduction in follicular fluid from carrier animals is consistent with the ~9-fold overexpression of SMAD family member 6 (SMAD6) in carriers that is inhibitory to this pathway
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