The alluaudite-type of structure is of huge research interest as an open matrix ensuring fast alkali-metal ion mobility, a property that could contribute to the development of novel electrode materials for rechargeable alkali-metal ion batteries. In this contribution, we provide new data on the formation of well-crystallized sodium manganese sulfates Na 2+d Mn 2Àd/2 (SO 4 ) 3 with an alluaudite-type of structure by simple dehydratation of the corresponding dihydrate Na 2 Mn(SO 4 ) 3 $2H 2 O with a kröhnkite-type of structure. The structure of Na 2+d Mn 2Àd/2 (SO 4 ) 3 is determined on the basis of Rietveld refinement of powder XRD patterns, infrared (IR) and Raman spectroscopy and electron paramagnetic resonance at X-and Q-band frequencies (EPR). From a structural point of view, the release of two H 2 O molecule from the kröhnkite phase takes place by a transformation of the infinite [Mn(SO 4 ) 2 (H 2 O) 2 ] chains into Mn 2 O 10 dimers bounded by distorted Na(1)O-polyhedra. The anhydrous sulfates are able to participate in the electrochemical reaction delivering a reversible capacity of 135 mA h g À1 , when they are used as cathode materials in lithium ion cells. The stability of the alluaudite phase Na 2+d Mn 2Àd/2 (SO 4 ) 3 in the lithium electrolyte solution and the mechanism of the electrochemical reaction are discussed on the basis of ex situ EPR, IR and Raman spectroscopy. This is a first report on electrochemical activity of manganese-based sulfate with an alluaudite-type of structure.

SumninryThe feasibility to avoid the distillation in the case of refractometric determination of the ethanol concentration in fermentation samples is examined. The results obtained show that the ethanol concentration in the range 0 to 100 g .1-1 can be easily determined by means of benzyl alcohol extraction and refractometry. Despite the availability of several different methods for ethanol concentration determination (gas chromatography [l], enzyme [2--41 and chemical [5, 61, methods, the refractometry finds wide application to the control of alcohol production [7-91. This method is used after the sample is distilled and the ethanol concentration is determined by measuring the distillate refraction. Distillation is an obligatory step of treatment by most of the ethanol assaying methods and it is considerably time-consuming. VARMA et al. propose the use of a n alternative ethanol separation method -solvent extraction, followed by gas chromatography analysis [lo].The objective of our investigation was by using solvent extraction in combination with refractometry to devise a rapid and easily applicable method for determination of ethanol concentration in fermentation broths. Materials and Methods Organic SolventsThe following solvents were used for the extraction: n-butanol, toluol, and benzyl alcohol, pfa. For the preparation of standard solutions absolute ethyl alcohol, pfs, was used. Fermentable SugarsIn order to investigate the influence of the presented sugars on the results for the ethanol concentration in the samples, standard solutions of the following sugars were examined: glucose, lactose, sucrose, pfa. Solutions of substrates used in the industrial alcohol production (molasses with 46.7% fermentable sugar content and dried whey ultrafiltrate with 99% lactose content) were studied as well.

This is the first experimental evidence for the operation of sodium cobalt-manganese sulfate, Na2+2δ(Co0.63Mn0.37)2−δ(SO4)3, at potentials higher than 4.0 V vs. Li/Li+.

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Studies of the biomass production during a continuous cultivation of yeasts on a nutrient medium, prepared from a hydrolysate from the production of microcrystalline cellulose, have been carried out. A new strain of yeasts has been used. Its cultivation has been achieved without addition of biostimulntors to the nutrient medium in spite of their absence in the initial hydrolysate. Practicslly EL complete assimilation of sugars has been .achieved at high dilution rates ( D = 0.25 to 0.50 h-1). The yield of biomass achieved is above 50% compared to the initial sugars and it contains 48.89% true protein. The results obtained offer the possibility of a complex utilization of the products of cellulose hydrolysis in the production of microcrystalline cellulose with a realization of a waste free technology.