Pretreatment research

The effective pretreatments for enzymatic hydrolysis of cellulose in hardwoods and agricultural residues have been developed over the past 90 years and new or improved ones are still being developed. The initial impetus for pretreatment research was the expansion of a feed base for ruminants (i.e., cattle and sheep). The concentration of pretreatment research on animal feed preparation placed an additional burden on researchers, because the product must be not only fully convertible to animal live-weight, but also nontoxic and palatable. Early feeding trials of pretreated fine sawdust to cattle produced very dismal results (55). This may be the reason, besides the... 

Dale BE, Ong RG. (2012). Energy, wealth, and human development why and how biomass pretreatment research must improve. Biotechnol Prog, 28(4), 893-898. 

The major water desalination processes that ate currendy in use or in advanced research stages are described herein. Information on detailed modeling can be found in the Hterature cited. The major texts on water desalination written since the 1980s are those by Spiegler and Laird (47), Khan (48), which contains many practical design aspects, Lior (49) on the measurements and control aspects, Heitman (40) on pretreatment and chemistry aspects, and Spiegler and El-Sayed (50), an overview primer. Extensive data sources are provided in References 39 and 51. 

Methods for recycling used plastic materials are reviewed. Emphasis is placed on the research projects into chemical recycling methods for used plastics at the Leuna location. These include development of a process for the thermaL thermooxidative pretreatment of used plastic materials, utilisation of pretreated used plastic materials in the visbreaker by gasification and by hydrogenation and the production of wax oxidates from pretreated used plastics. The results are discussed. 

Figure 3. Relationship between levels of protein kinase C and inhibition of EGF binding to Swiss 3T3 cells by PDBu and palytoxin. Confluent quiescent Swiss 3T3 cells were pretreated for 72 hr with 0.1% FCS plus solvent ( ), 20 nM PDBu (o), 200 nM PDBu (A), or 2000 nM ( ). Cells were then washed and treated with either 200 nM PDBu (A) or 11 pM palytoxin (B) for the times shown and assayed as in Figure 1. Other conditions were as described in the legend to Figure 2. The data for 200 nM PDBu are composites of two independent experiments. (Reproduced with permission from Ref. 33. Copyright 1987 Cancer Research, Inc.)...

Using these rhelogical methods laboratories for quality control and research and development have good tools to characterize pectins in gels and solutions. The most important points are the reproducable handling, pretreatment, and measurement of the samples and the knowledge which information can be derived from the measured data regarding the texture, the production parameters, and the sensory evaluation of the product. 

For the spectrophotometric method, the evolved carbon disulfide is reacted with copper acetate and diethylamine to form a yellow copper complex which can be measured at 435 nm." The recoveries range between 70 and 90%. Reproducibility of this method was improved by reducing the time and the mode of sample pretreatment. Since all alkylenebis(dithiocarbamates) decompose to carbon disulfide by acid degradation, the above analytical methods are not selective. The result is the measured total residues of all alkylenebis(dithiocarbamates) related products. However, this method is recommended as standard method S15 for alkylenebis(dithiocarbamates) by the German Research Association. ... 

Givens, S. and Cable, J., Case study—a tale of two industries, pretreatment of confectionary and bakery wastewaters. 1988 Food Processing Waste Conference, presented by the Georgia Tech Research Institute, Atlanta, Georgia, October 31-November 2, 1988. 

One of the earliest fibre pretreatments for improving the dyeability of cotton is of course mercerisation (section 10.5.4). However, more recent research interest in this area has been generated by environmental concerns about reactive dyeing, aiming to enhance substantivity for the modified fibre so that higher absorption and fixation are obtained. This results in less dye (hydrolysed or still active) in the effluent. A further objective is to minimise the usage of electrolyte in the application process. This area has been thoroughly reviewed [392,393]. 

Surface-water samples are usually collected manually in precleaned polyethylene bottles (from a rubber or plastic boat) from the sea, lakes, and rivers. Sample collection is performed in the front of the bow of boats, against the wind. In the sea, or in larger inland lakes, sufficient distance (about 500 m) in an appropriate wind direction has to be kept between the boat and the research vessel to avoid contamination. The collection of surface water samples from the vessel itself is impossible, considering the heavy metal contamination plume surrounding each ship. Surface water samples are usually taken at 0.3-1 m depth, in order to be representive and to avoid interference by the air/water interfacial layer in which organics and consequently bound heavy metals accumulate. Usually, sample volumes between 0.5 and 21 are collected. Substantially larger volumes could not be handled in a sufficiently contamination-free manner in subsequent sample pretreatment steps. 

Chromium has proved effective in counteracting the deleterious effects of cadmium in rats and of vanadium in chickens. High mortality rates and testicular atrophy occurred in rats subjected to an intraperitoneal injection of cadmium salts however, pretreatment with chromium ameliorated these effects (Stacey et al. 1983). The Cr-Cd relationship is not simple. In some cases, cadmium is known to suppress adverse effects induced in Chinese hamster (Cricetus spp.) ovary cells by Cr (Shimada et al. 1998). In southwestern Sweden, there was an 80% decline in chromium burdens in liver of the moose (Alces alces) between 1982 and 1992 from 0.21 to 0.07 mg Cr/kg FW (Frank et al. 1994). During this same period in this locale, moose experienced an unknown disease caused by a secondary copper deficiency due to elevated molybdenum levels as well as chromium deficiency and trace element imbalance (Frank et al. 1994). In chickens (Gallus sp.), 10 mg/kg of dietary chromium counteracted adverse effects on albumin metabolism and egg shell quality induced by 10 mg/kg of vanadium salts (Jensen and Maurice 1980). Additional research on the beneficial aspects of chromium in living resources appears warranted, especially where the organism is subjected to complex mixtures containing chromium and other potentially toxic heavy metals. 

Chlordane interachons with other agricultural chemicals are significant and merit additional research. In one study, male Japanese quail (Coturnix japonica) pretreated for 8 weeks with 10 mg chlordane/kg diet had increased resistance to parathion, but not to paraoxon, as judged by cholinesterase activity (Ludke 1977). In another study, northern bobwhites (Colinus virginianus) treated with 10 mg chlordane/kg diet for 10 weeks, followed by endrin stress, had greater accumulations of chlordane in the brain than did birds treated only with chlordane (Ludke 1976). 

Among the main goals of electrochemical research are the design, characterization and understanding of electrocatalytic systems, (1-2) both in solution and on electrode surfaces. (3.) Of particular importance are the nature and structure of reactive intermediates involved in the electrocatalytic reactions.(A) The nature of an electrocatalytic system can be quite varied and can include activation of the electrode surface by specific pretreatments (5-9) to generate active sites, deposition or adsorption of metallic adlayers (10-111 or transition metal complexes. (12-161 In addition the electrode can act as a simple electron shuttle to an active species in solution such as a metallo-porphyrin or phthalocyanine. 

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