Kondisi Optimum Pemisahan Aseton Dari Campuran Aseton-Etanol-Air-n–Butanol Dengan Kolom Distilasi Vacuum

Fermenting molasses using clostridium acetobutilycum can produce a mixture of acetone (1)/ethanol (2)/water (3)/n-butanol (4). The fermentation products are then separated and purified in a series of distillation column. In this work the products are 99.5-wt % of acetone and 99 % recovery.This work is primarily concerned with the effect of operating pressure on the distillation column performance. Distillation columns were designed using computer programs written in VISUAL FORTRAN 5.0. A rigorous equilibrium based computation method due to Wang-Henke that taking into account the effects of non-equal molar overflow and non-ideal vapor-liquid equilibrium was used in study. UNIQUAC, a method of estimating activity coefficient in non-ideal liquid mixtures, was used to model the vapor–liquid equilibrium. The column performance was studied by varying the operating pressure that is constrained by the cooling water temperature in the condenser. The numbers of plates are 50 and feed plate location at 12th plate below the condenser for acetone column. Variation of pressure 0.7 to 0.6 atm for acetone column will decrease 6.03 % reflux ratios, 4.3% condenser and 4.78% reboiler duty. Optimum condition for acetone column was 0.6 atm

Biokonversi Serat Kelapa Sawit Menjadi Glukosa Dengan Diluted-acid Hydrothermal Treatment

Fiber cake (FC) is a one of effluent of Crude Palm Oil (CPO) industry. This effluent can be decreased by using FC for bioethanol production. FC is actually Palm Kernel Press Cake (PKC) a residue of palm oil extraction, which containing 57.9% cellulose and 18% klason lignin, and containing 14.94% hemicellulose. This study aimed to determined the effect of fiber concentrations and reaction time for glucose production to investigate the structure of morphology and crystalinity of the fiber cake before and after hydrothermal treatment. Fiber cake was treated by hydrothermal reactor using catalysts 2% H2SO4 (v/v) and 150 oC for 2 hour. Variations concentration of fiber cake which is 2.5%; 5%; 7.5%; and 10% w/v and time variations for 1, 2, 3, 4 hours. The highest glucose concentration was found at 2.5% FC for 3 hour about 2.336 ± 0.015 mg/mL. Scanning electron microscope (SEM analysis results and X-Ray Diffraction (XRD) is known the smooth surface structure to be broken an rough after the hydrolysis process and also improvement of the crystal structure of fiber cake from 27.57% to 31.15%

Pengaruh Konsentrasi Hcl Dan Ph Pada Ekstraksi Pektin Dari Albedo Durian Dan Aplikasinya Pada Proses Pengentalan Karet

: Pectin is a complex polysaccharides compound which contained in plant cell walls. It is used in food manufacturing processes, adsorbent for waste water treatment and coagulant for rubber industry. Albedo durian was one of the potential sources of pectin, because albedo durian is consist of pectin compound. Acid extraction process was used to decompose pectin compound which contained in albedo durian. In this research, twenty grams of albedo durian was reacted with hydrochloric acid using stirred tank reactor. This process was conducted at temperature 90 0C for 1 hour in various solvent concentration and PH. The purpose of this research was to study the effect of solvent concentration and PH in pectin extraction process and the effect of adding pectin in process of latex coagulation. The result showed that the higher PH and solvent concentration, the higher yield of pectin. The maximum yield of pectin which was obtained in this research is 89.55%. The methoxyl contain and galacturonic which was obtained in this research between 2.430-3.13% and 67.65-82.02%, rescpectively. The Minimum time for latex coagulation about 5 minute using ratio pectin and latex 5:5

Chiral drag force

We provide a holographic evaluation of novel contributions to the drag force acting on a heavy quark moving through strongly interacting plasma. The new contributions are chiral in that they act in opposite directions in plasmas containing an excess of left- or right-handed quarks and in that they are proportional to the coefficient of the axial anomaly. These new contributions to the drag force act either parallel to or antiparallel to an external magnetic field or to the vorticity of the fluid plasma. In all these respects, these contributions to the drag force felt by a heavy quark are analogous to the chiral magnetic effect on light quarks. However, the new contribution to the drag force is independent of the electric charge of the heavy quark and is the same for heavy quarks and antiquarks. We show that although the chiral drag force can be non-vanishing for heavy quarks that are at rest in the local fluid rest frame, it does vanish for heavy quarks that are at rest in a suitably chosen frame. In this frame, the heavy quark at rest sees counterpropagating momentum and charge currents, both proportional to the axial anomaly coefficient, but feels no drag force. This provides strong concrete evidence for the absence of dissipation in chiral transport, something that has been predicted previously via consideration of symmetries. Along the way to our principal results, we provide a general calculation of the corrections to the drag force due to the presence of gradients in the flowing fluid in the presence of a nonzero chemical potential. We close with a consequence of our result that is at least in principle observable in heavy ion collisions, namely an anticorrelation between the direction of the CME current for light quarks in a given event and the direction of the kick given to the momentum of all the heavy quarks and antiquarks in that event.Comment: 28 pages, small improvement to the discussion of gravitational anomaly, references adde

Oxytocin and cholecystokinin secretion in women with colectomy

BACKGROUND: Cholecystokinin (CCK) concentrations in plasma have been shown to be significantly higher in colectomised subjects compared to healthy controls. This has been ascribed to reduced inhibition of CCK release from colon. In an earlier study CCK in all but one woman who was colectomised, induced release of oxytocin, a peptide present throughout the gastrointestinal (GI) tract. The aim of this study was thus to examine if colectomised women had a different oxytocin response to CCK compared to healthy controls. METHODS: Eleven women, mean age 34.4 ± 2.3 years, who had undergone colectomy because of ulcerative colitis or constipation were studied. Eleven age-matched healthy women served as controls. All subjects were fasted overnight and given 0.2 μg/kg body weight of CCK-8 i.v. in the morning. Samples were taken ten minutes and immediately before the injection, and 10, 20, 30, 45, 60, 90 and 120 min afterwards. Plasma was collected for measurement of CCK and oxytocin concentrations. RESULTS: The basal oxytocin and CCK concentrations in plasma were similar in the two groups. Intravenous injection of CCK increased the release of oxytocin from 1.31 ± 0.12 and 1.64 ± 0.19 pmol/l to 2.82 ± 0.35 and 3.26 ± 0.50 pmol/l in controls and colectomised women, respectively (p < 0.001). Given the short half-life of CCK-8 in plasma, the increased concentration following injection could not be demonstrated in the controls. On the other hand, in colectomised women, an increase of CCK in plasma was observed for up to 20 minutes after the injection, concentrations increasing from 1.00 ± 0.21 to a maximum of 1.81 ± 0.26 pmol/l (p < 0.002). CONCLUSION: CCK stimulates the release of oxytocin in women. There is no difference in plasma concentrations between colectomised and controls. However, colectomy seems to reduce the metabolic clearance of CCK. The hyperCCKemia in patients who had undergone colectomy is consequently not only dependent on CCK release, but may also depend on reduced clearance

Thermodynamics and Instabilities of a Strongly Coupled Anisotropic Plasma

We extend our analysis of a IIB supergravity solution dual to a spatially anisotropic finite-temperature N=4 super Yang-Mills plasma. The solution is static, possesses an anisotropic horizon, and is completely regular. The full geometry can be viewed as a renormalization group flow from an AdS geometry in the ultraviolet to a Lifshitz-like geometry in the infrared. The anisotropy can be equivalently understood as resulting from a position-dependent theta-term or from a non-zero number density of dissolved D7-branes. The holographic stress tensor is conserved and anisotropic. The presence of a conformal anomaly plays an important role in the thermodynamics. The phase diagram exhibits homogeneous and inhomogeneous (i.e. mixed) phases. In some regions the homogeneous phase displays instabilities reminiscent of those of weakly coupled plasmas. We comment on similarities with QCD at finite baryon density and with the phenomenon of cavitation.Comment: 62 pages, 13 figures; v2: typos fixed, added reference

The Eurasian Modern Pollen Database (EMPD), version 2

The Eurasian (née European) Modern Pollen Database (EMPD) was established in 2013 to provide a public database of high-quality modern pollen surface samples to help support studies of past climate, land cover, and land use using fossil pollen. The EMPD is part of, and complementary to, the European Pollen Database (EPD) which contains data on fossil pollen found in Late Quaternary sedimentary archives throughout the Eurasian region. The EPD is in turn part of the rapidly growing Neotoma database, which is now the primary home for global palaeoecological data. This paper describes version 2 of the EMPD in which the number of samples held in the database has been increased by 60 % from 4826 to 8134. Much of the improvement in data coverage has come from northern Asia, and the database has consequently been renamed the Eurasian Modern Pollen Database to reflect this geographical enlargement. The EMPD can be viewed online using a dedicated map-based viewer at https://empd2.github.io and downloaded in a variety of file formats at https://doi.pangaea.de/10.1594/PANGAEA.909130 (Chevalier et al., 2019)Swiss National Science Foundation | Ref. 200021_16959