An approach to mixed systems co-synthesis

Author(s):  
T. Benner ◽  
R. Ernst
Keyword(s):  
1985 ◽  
Vol 17 (11-12) ◽  
pp. 325-326 ◽  
Author(s):  
H J. G. W. Donker ◽  
P. Opic ◽  
H. P. de Vries

Ca. 60 % of the Dutch activated sludge plants consist of completely mixed systems, experiments have been carried out in completely mixed pilot plants to study the biological P-removal. The research was carried out in two pilot plants. The pilot plants consisted of: anaerobic reactor, anoxic reactor, aerobic reactor and a clarifier. All the reactors were completely mixed. Both plants were fed with settled domestic waste water at a sludge loading of 400 and 250 g COD/kg sludge.day respectively. The results are given below:sludge loading (g COD/kg sludge.day)400400250ratio Anaerobic : Anoxic : Aerobic1: 1:2,71:1:4,11:1:2,7P-removal (%)802875N-removal (%)505065COD-removal (%)858585 It has been shown that there is no significant difference between the results at the two different sludge loadings. Remarkable is the difference between the ratio 1:1:2,7 in combination with the internal recirculation flow anoxic-anaerobic of 160 % and the ratio 1:1:4,1 with a recirculation flow of 30 %. During the start-up at a sludge loading of 250 g COD/kg sludge.day and an internal recirculation flow of 30 %, bulking sludge developed almost immediately. The Premoval was completely disturbed. Increasing the internal recirculation flow to 160% had a positive effect on settling properties and P-removal. This investigation has pointed out that a completely mixed system is suitable for biological P-removal, without negatively affecting the nitrification. Important factors in the process are the ratio anaerobic:anoxic:aerobic and the recirculation flows.


1994 ◽  
Vol 59 (8) ◽  
pp. 1738-1744
Author(s):  
Vladislav Holba

The solubilities of tetraalkylammonium dianilinetetraisothiocyanatochromates(III) (alkyl = methyl, ethyl, 1-propyl, and 1-butyl) in water, water - methanol, water - tert-butyl alcohol and water - acetonitrile solutions were measured at 25 °C. The results were used to evaluate the activity coefficients and Gibbs energies of transfer of the saturating salts from water to the mixed systems. The Gibbs energies of transfer of the [Cr(C6H5NH2)2(NCS)4]- ion were obtained by means of known ionic transfer functions for the tetraalkylammonium ions based on the TATB assumption.


Probus ◽  
2021 ◽  
Vol 33 (1) ◽  
pp. 57-93
Author(s):  
Ana Lívia Agostinho ◽  
Larry M. Hyman

Abstract Creole languages have generally not figured prominently in cross-linguistic studies of word-prosodic typology. In this paper, we present a phonological analysis of the prosodic system of Lung’Ie or Principense (ISO 639-3 code: pre), a Portuguese-lexifier creole language spoken in São Tomé and Príncipe. Lung’Ie has produced a unique result of the contact between the two different prosodic systems common in creolization: a stress-accent lexifier and tone language substrates. The language has a restrictive privative H/Ø tone system, in which the /H/ is culminative, but non-obligatory. Since rising and falling tones are contrastive on long vowels, the tone must be marked underlyingly. While it is clear that tonal indications are needed, Lung’Ie reveals two properties more expected of an accentual system: (i) there can only be one heavy syllable per word; (ii) this syllable must bear a H tone. This raises the question of whether syllables with a culminative H also have metrical prominence, i.e. stress. However, the problem with equating stress with H tone is that Lung’Ie has two kinds of nouns: those with a culminative H and those which are toneless. The nouns with culminative H are 87% of Portuguese origin, incorporated through stress-to-tone alignment, while the toneless ones are 92% of African origin. Although other creole languages have been reported with split systems of “accented” vs. fully specified tonal lexemes, and others with mixed systems of tone and stress, Lung’Ie differs from these cases in treating African origin words as toneless, a quite surprising result. We consider different analyses and conclude that Lung’Ie has a privative /H/ tone system with the single unusual stress-like property of weight-to-tone.


2004 ◽  
Vol 20 (1) ◽  
pp. 227-253 ◽  
Author(s):  
Ram Mudambi ◽  
Pietro Navarra

2005 ◽  
Vol 38 (2) ◽  
pp. 171-188 ◽  
Author(s):  
Terry D. Clark ◽  
Jill N. Wittrock

Efforts to test Duverger’s law in the new democracies of postcommunist Europe have had mixed results. Research argues that mixed systems have an effect on the number of effective parties that is distinct from that of single-mandate district and proportional representation systems. Less attention has been given to the effect of other institutions on the party system, particularly strong presidents. Analyzing election results in postcommunist Europe, the authors find support for Duverger’s law after controlling for the strength of the executive. They argue that strong presidents substantially reduce the incentive for parties to seize control of the legislative agenda. Hence, the restraint that electoral systems exercise on the proliferation of parties and independent candidates is weakened. The authors find that a further consequence of strong presidents is that the incentive for majority control of committees and the legislative agenda is weakened.


Probus ◽  
2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Ana Lívia Agostinho ◽  
Larry M. Hyman

Abstract Creole languages have generally not figured prominently in cross-linguistic studies of word-prosodic typology. In this paper, we present a phonological analysis of the prosodic system of Lung’Ie or Principense (ISO 639-3 code: pre), a Portuguese-based creole language spoken in São Tomé and Príncipe. Lung’Ie has produced a unique result of the contact between the two different prosodic systems common in creolization: a stress-accent lexifier and tone language substrates. The language has a restrictive privative H/Ø tone system, in which the /H/ is culminative, but non-obligatory. Since rising and falling tones are contrastive on long vowels, the tone must be marked underlyingly. While it is clear that tonal indications are needed, Lung’Ie reveals two properties more expected of an accentual system: (i) there can only be one heavy syllable per word; (ii) this syllable must bear a H tone. This raises the question of whether syllables with a culminative H also have metrical prominence, i.e. stress. However, the problem with equating stress with H tone is that Lung’Ie has two kinds of nouns: those with a culminative H and those which are toneless. The nouns with culminative H are 87% of Portuguese origin, incorporated through stress-to-tone alignment, while the toneless ones are 92% of African origin. Although other creole languages have been reported with split systems of “accented” vs. fully specified tonal lexemes, and others with mixed systems of tone and stress, Lung’Ie differs from these cases in treating African origin words as toneless, a quite surprising result. We consider different analyses and conclude that Lung’Ie has a privative /H/ tone system with the single unusual stress-like property of weight-to-tone.


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