Maximum-entropy data analysis

The reconstruction of physical quantities from (computer-) experimental data is very often hampered by the presence of noise, insufficient information and above all by the ill-posed nature of the underlying inversion problem. It will be demonstrated that the maximum entropy concepts is particularly suited for this type of data-analysis problems. It is based on Bayesian statistics and provides a consistent probabilistic theory to obtain unbiased results, independent of any model assumptions. This is particularly desirable if there is no additional information to justify these hypotheses. If, on the other hand, additional prior knowledge is available, it can be effectively incorporated into the computation, leading to more stringent confidence intervals.     

Plant processing by simultaneous lactic acid fermentation and enzyme hydrolysis

Traditional ensiling of plant material by anaerobic lactic acid fermentation was combined with enzymatic hydrolysis (ENLAC for short) with cell wall degrading enzymes (hemicellulases, cellulases, and pectinases) to increase fiber digestibility or to increase the recovery of cell content from plants. Such findings were made using 0.015% (w/w, wet basis) Phylacell® enzyme preparation by ENLAC of corn and corn-sorghum mixtures, but not of forage grasses. Addition to alfalfa of a mixture of cell wall degrading enzymes, such as NOVO Viscozyme® together with NOVO Celluclast® each at 0.2–1.0% (w/w, wet basis), resulted in more rapid ensiling and improvement of rumen digestibility of silage by 20%. After 20 d of ensiling at 25 °C when the same enzymes were added to alfalfa at the 1.0% level, protein recovery by pressing increased by 35%, β-carotene recovery by 80%, and chlorophyll/xanthophyll recovery by 30%. ENLAC with the same enzymes also increased the recovery of sclareol from muscatel sage by 400%.

     

On the differentiability of maps into Lie transformation groups

Let G be a Lie transformation group on a manifold M. Then a map f: NG is differentiable, iff for every point pM the map q f(q)·p is differentiable.     

4,4-Disubstituierte Imidazol-Derivate aus der Umsetzung von 3-Amino-2H-azirinen mit Salicylamid

4,4-Disubstituted Imidazole Derivatives from the Reaction of 3-Amino-2H-azirines with Salicylamide Reaction of 3-amino-2H-azirines 1a–c with salicylamide ( 7 ) in MeCN leads to imidazoles 10 and 11 in different rates, depending on the conditions. In the case of 1a and 1b, 11a and 11b , respectively, have been obtained as the main product at 50°; in reactions at 80°, 10a and 10b are the favored products (Tables 1 and 2). 2,2-Dimethyl-3-(N-methyl-N-phenylamino)-2H-azirine ( 1c ) reacts with 7 in MeCN mainly to 2-(2-hydroxyphenyl)-5,5-dimethyl-3,5-dihydroimidazol-4-one ( 10a ); in boiling toluene, 11c is formed with low preference (Table 3). The structure of the products has been established by spectroscopic means, and in the case of 10b and 11c , by X-ray crystallography. Two different reaction mechanisms for the formation of the products are discussed (Scheme 2).     

Type I and type II sensitizers based on Rose Bengal onium salts

Abstract— New Rose Bengal oniurn salts containing one or two iodonium, sulfonium, phosphonium, and pyrylium ions have been prepared as part of a program to develop sensitizers which can function as Type I radical photoinitiators and Type II energy transfer donors depending on experimental conditions. The absorption spectra of the onium salts in different solvents indicate an equilibrium between tight and loose ion pairs which depends on the solvent polarity, the cation and concentration. Typical Rose Bengal photochemistry requires the structure be that of the loose ion pair in the solvent of choice. Similar factors also influence bleaching behavior, and bleaching is the result of electron transfer processes. The quantum yields of singlet oxygen production from the onium salts in polar solvents are similar to that of the parent, Rose Bengal disodium salt.