Evaluation of First-Order, Second-Order, and Surface-Limiting Reactions in Anaerobic Hydrolysis of Cattle Manure

2006 ◽  
Vol 23 (6) ◽  
pp. 970-980 ◽  
Author(s):  
M. Myint ◽  
N. Nirmalakhandan
2020 ◽  
Vol 4 (1) ◽  
pp. 120-131
Author(s):  
Sitti Rahmawati ◽  
Asnila Asnila ◽  
Suherman Suherman ◽  
Paulus Hengky Abram

One of the plants that can be used as raw material for making sugar is plants that contain starch content such as avocado seeds. This study aims to determine the reaction order, the reaction rate constant from the hydrolysis of avocado seed starch using HCl. The method of this research is to determine the optimum concentration of HCl hydrolysis reaction from avocado seed starch using various concentrations of HCl (0.5 M; 1 M; 1.5 M; 2 M; 2.5 M) at the optimum temperature and stirring time (90oC for 70 minute). The hydrolysis process was followed by neutralization using 5 M NaOH solution and evaporated to obtain concentrated glucose, glucose was analyzed qualitatively and quantitatively by the Benedict method and the phenol sulfuric acid method. Based on the results of the maximum glucose levels obtained from the hydrolysis of variations in the concentration of HCl avocado seed starch, HCl 1.5 M. Furthermore, determine the kinetics of the starch hydrolysis reaction using time variations (30, 40, 50, 60 and 70) minutes at 90oC and concentrations The HCl 1.5 M. reaction order is determined by the intral method and the graph method. Determination of the first order graph method is done by plotting the value of ln [A] versus time, while the second order by plotting the value of 1 / [A] versus time. The first order with a 93% confidence level was obtained from the value of R2 = 0.9312, while the second order was 85% obtained from the value of R2 = 0.8581. Determination of the order of the integral method k value tends to remain in the first order formula with an average of k = 0.01962 minutes-1. Based on the two methods, it can be determined that the kinetics of the avocado seed starch hydrolysis reaction follows a first-order reaction.


1973 ◽  
Vol 28 (1-2) ◽  
pp. 12-22 ◽  
Author(s):  
W. Roebke ◽  
M. Schöneshöfer ◽  
A. Henglein

A polymer (CHS2)n and sulfate are formed in the γ-irradiation of deaerated aqueous carbon disulfide solutions. The G-values are 3.6 and 0.41, respectively. In the presence of N,O, G (polymer) is decreased while G(SO4-) is increased. G(SO4-) can be decreased by isopropanol. G(polymer) is increased by H+ ions and reaches a value of 5 below pH = 2. Formic acid, hydrogen sulfide and carbonate are formed in the hydrolysis of the polymer. Pyrolysis at first leads to a red oil consisting of oligomer (HCS2)n and finally to H2S, CS2 plus a residue containing much carbon. The structure of the polymer is discussed.Pulse radiolytic experiments show that CS2 reacts with eaq (3.1 × 1010M-1s-1) and OH(7.4 × 109M-1s-1) in a diffusion controlled manner. The first product of the reaction with OH is SC(OH)S. The pK of the electrolytic dissociationSC(OH)Ṣ ⇄ SC(O-)S + H+is 4.4. The absorption spectra of SC(OH)S and SC(O-)S were measured. SC(OH)S disappears by second order with 2k = 1.6 × 109M-1s-1 at pH = 6. The product is a bivalent acid, the spectrum of which was measured. The second pK of this acid is 5.7, its first pK is lower than 4.Both eāq and H react with CS2 to form SCS-. The absorption spectrum of this radical anion was measured. The pK of the equilibriumSCSH ⇄SCS- + H+is about 1.6. In solutions of low H+-concentration, SCS- disappears by second order with 2k = 6.4 × 109M-1s-1. The structure of dithioformic acid is attributed to the resulting product. In solutions of high H+-concentration, SCS- (or SCSH) disappears by a fast first order process, the rate constant of which increases with H+-concentration. The carbeniat neutralizationis believed to be responsible for this process. The rate constant is 5.1 × 107M-1S-1. The spectrum of SC(H)S was measured. This radical disappears by second order with 2k = 7.4 × 109M-1s-1. The spectrum of the resulting product was also determined.It is concluded that the formation of the polymer and of SO4- occurs in processes in which the first products from the attack of eāq, H and OH on CS2 as well as molecules which were built up from these products are involved.


1997 ◽  
Vol 36 (04/05) ◽  
pp. 315-318 ◽  
Author(s):  
K. Momose ◽  
K. Komiya ◽  
A. Uchiyama

Abstract:The relationship between chromatically modulated stimuli and visual evoked potentials (VEPs) was considered. VEPs of normal subjects elicited by chromatically modulated stimuli were measured under several color adaptations, and their binary kernels were estimated. Up to the second-order, binary kernels obtained from VEPs were so characteristic that the VEP-chromatic modulation system showed second-order nonlinearity. First-order binary kernels depended on the color of the stimulus and adaptation, whereas second-order kernels showed almost no difference. This result indicates that the waveforms of first-order binary kernels reflect perceived color (hue). This supports the suggestion that kernels of VEPs include color responses, and could be used as a probe with which to examine the color visual system.


2017 ◽  
Vol 9 (3) ◽  
pp. 17-30
Author(s):  
Kelly James Clark

In Branden Thornhill-Miller and Peter Millican’s challenging and provocative essay, we hear a considerably longer, more scholarly and less melodic rendition of John Lennon’s catchy tune—without religion, or at least without first-order supernaturalisms (the kinds of religion we find in the world), there’d be significantly less intra-group violence. First-order supernaturalist beliefs, as defined by Thornhill-Miller and Peter Millican (hereafter M&M), are “beliefs that claim unique authority for some particular religious tradition in preference to all others” (3). According to M&M, first-order supernaturalist beliefs are exclusivist, dogmatic, empirically unsupported, and irrational. Moreover, again according to M&M, we have perfectly natural explanations of the causes that underlie such beliefs (they seem to conceive of such natural explanations as debunking explanations). They then make a case for second-order supernaturalism, “which maintains that the universe in general, and the religious sensitivities of humanity in particular, have been formed by supernatural powers working through natural processes” (3). Second-order supernaturalism is a kind of theism, more closely akin to deism than, say, Christianity or Buddhism. It is, as such, universal (according to contemporary psychology of religion), empirically supported (according to philosophy in the form of the Fine-Tuning Argument), and beneficial (and so justified pragmatically). With respect to its pragmatic value, second-order supernaturalism, according to M&M, gets the good(s) of religion (cooperation, trust, etc) without its bad(s) (conflict and violence). Second-order supernaturalism is thus rational (and possibly true) and inconducive to violence. In this paper, I will examine just one small but important part of M&M’s argument: the claim that (first-order) religion is a primary motivator of violence and that its elimination would eliminate or curtail a great deal of violence in the world. Imagine, they say, no religion, too.Janusz Salamon offers a friendly extension or clarification of M&M’s second-order theism, one that I think, with emendations, has promise. He argues that the core of first-order religions, the belief that Ultimate Reality is the Ultimate Good (agatheism), is rational (agreeing that their particular claims are not) and, if widely conceded and endorsed by adherents of first-order religions, would reduce conflict in the world.While I favor the virtue of intellectual humility endorsed in both papers, I will argue contra M&M that (a) belief in first-order religion is not a primary motivator of conflict and violence (and so eliminating first-order religion won’t reduce violence). Second, partly contra Salamon, who I think is half right (but not half wrong), I will argue that (b) the religious resources for compassion can and should come from within both the particular (often exclusivist) and the universal (agatheistic) aspects of religious beliefs. Finally, I will argue that (c) both are guilty, as I am, of the philosopher’s obsession with belief. 


1985 ◽  
Vol 50 (4) ◽  
pp. 845-853 ◽  
Author(s):  
Miloslav Šorm ◽  
Miloslav Procházka ◽  
Jaroslav Kálal

The course of hydrolysis of an ester, 4-acetoxy-3-nitrobenzoic acid catalyzed with poly(1-methyl-3-allylimidazolium bromide) (IIa), poly[l-methyl-3-(2-propinyl)imidazolium chloride] (IIb) and poly[l-methyl-3-(2-methacryloyloxyethyl)imidazolium bromide] (IIc) in a 28.5% aqueous ethanol was investigated as a function of pH and compared with low-molecular weight models, viz., l-methyl-3-alkylimidazolium bromides (the alkyl group being methyl, propyl, and hexyl, resp). Polymers IIb, IIc possessed a higher activity at pH above 9, while the models were more active at a lower pH with a maximum at pH 7.67. The catalytic activity at the higher pH is attributed to an attack by the OH- group, while at the lower pH it is assigned to a direct attack of water on the substrate. The rate of hydrolysis of 4-acetoxy-3-nitrobenzoic acid is proportional to the catalyst concentration [IIc] and proceeds as a first-order reaction. The hydrolysis depends on the composition of the solvent and was highest at 28.5% (vol.) of ethanol in water. The hydrolysis of a neutral ester, 4-nitrophenyl acetate, was not accelerated by IIc.


2009 ◽  
Vol 74 (1) ◽  
pp. 43-55 ◽  
Author(s):  
Dennis N. Kevill ◽  
Byoung-Chun Park ◽  
Jin Burm Kyong

The kinetics of nucleophilic substitution reactions of 1-(phenoxycarbonyl)pyridinium ions, prepared with the essentially non-nucleophilic/non-basic fluoroborate as the counterion, have been studied using up to 1.60 M methanol in acetonitrile as solvent and under solvolytic conditions in 2,2,2-trifluoroethan-1-ol (TFE) and its mixtures with water. Under the non- solvolytic conditions, the parent and three pyridine-ring-substituted derivatives were studied. Both second-order (first-order in methanol) and third-order (second-order in methanol) kinetic contributions were observed. In the solvolysis studies, since solvent ionizing power values were almost constant over the range of aqueous TFE studied, a Grunwald–Winstein equation treatment of the specific rates of solvolysis for the parent and the 4-methoxy derivative could be carried out in terms of variations in solvent nucleophilicity, and an appreciable sensitivity to changes in solvent nucleophilicity was found.


Author(s):  
Uriah Kriegel

Brentano’s theory of judgment serves as a springboard for his conception of reality, indeed for his ontology. It does so, indirectly, by inspiring a very specific metaontology. To a first approximation, ontology is concerned with what exists, metaontology with what it means to say that something exists. So understood, metaontology has been dominated by three views: (i) existence as a substantive first-order property that some things have and some do not, (ii) existence as a formal first-order property that everything has, and (iii) existence as a second-order property of existents’ distinctive properties. Brentano offers a fourth and completely different approach to existence talk, however, one which falls naturally out of his theory of judgment. The purpose of this chapter is to present and motivate Brentano’s approach.


Author(s):  
Tim Button ◽  
Sean Walsh

In this chapter, the focus shifts from numbers to sets. Again, no first-order set theory can hope to get anywhere near categoricity, but Zermelo famously proved the quasi-categoricity of second-order set theory. As in the previous chapter, we must ask who is entitled to invoke full second-order logic. That question is as subtle as before, and raises the same problem for moderate modelists. However, the quasi-categorical nature of Zermelo's Theorem gives rise to some specific questions concerning the aims of axiomatic set theories. Given the status of Zermelo's Theorem in the philosophy of set theory, we include a stand-alone proof of this theorem. We also prove a similar quasi-categoricity for Scott-Potter set theory, a theory which axiomatises the idea of an arbitrary stage of the iterative hierarchy.


2019 ◽  
Vol 17 (1) ◽  
pp. 544-556
Author(s):  
Yoke-Leng Sim ◽  
Beljit Kaur

AbstractPhosphate ester hydrolysis is essential in signal transduction, energy storage and production, information storage and DNA repair. In this investigation, hydrolysis of adenosine monophosphate disodium salt (AMPNa2) was carried out in acidic, neutral and alkaline conditions of pH ranging between 0.30-12.71 at 60°C. The reaction was monitored spectrophotometrically. The rate ranged between (1.20 ± 0.10) × 10-7 s-1 to (4.44 ± 0.05) × 10-6 s-1 at [NaOH] from 0.0008 M to 1.00M recorded a second-order base-catalyzed rate constant, kOH as 4.32 × 10-6 M-1 s-1. In acidic conditions, the rate ranged between (1.32 ± 0.06) × 10-7 s-1 to (1.67 ± 0.10) × 10-6 s-1 at [HCl] from 0.01 M to 1.00 M. Second-order acid-catalyzed rate constant, kH obtained was 1.62 × 10-6 M-1 s-1. Rate of reaction for neutral region, k0 was obtained from graphical method to be 10-7 s-1. Mechanisms were proposed to involve P-O bond cleavage in basic medium while competition between P-O bond and N-glycosidic cleavage was observed in acidic medium. In conclusion, this study has provided comprehensive information on the kinetic parameters and mechanism of cleavage of AMPNa2 which mimicked natural AMP cleavage and the action of enzymes that facilitate its cleavage.


2020 ◽  
Vol 10 (1) ◽  
pp. 001-010 ◽  
Author(s):  
Nikoletta Harsági ◽  
Betti Szőllősi ◽  
Nóra Zsuzsa Kiss ◽  
György Keglevich

Abstract The optimized HCl-catalyzed hydrolysis of alkyl diphenylphosphinates is described. The reaction times and pseudo-first-order rate constants suggested the iPr > Me > Et ∼ Pr ∼ Bu order of reactivity in respect of the alkyl group of the phosphinates. The MW-assisted p-toluenesulfonic acid (PTSA)-catalyzed variation means a better alternative possibility due to the shorter reaction times, and the alkaline hydrolysis is another option. The transesterification of alkyl diphenylphosphinates took place only in the presence of suitable ionic liquids, such as butyl-methylimidazolium hexafluorophosphorate ([bmim][PF6]) and butyl-methylimidazolium tetrafluoroborate ([bmim][BF4]). The application of ethyl-methylimidazolium hydrosulfate ([emim][HSO4]) and butyl-methylimidazolium chloride ([bmim][Cl]) was not too efficient, as the formation of the ester was accompanied by the fission of the O–C bond resulting in the formation of Ph2P(O)OH. This surprising transformation may be utilized in the phosphinate → phosphinic acid conversion.


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