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PubMed2001

The biotechnological control of pitch in paper pulp manufacturing.

At present, microbial and enzymatic preparations for the control of triglyceride-containing pitch deposits during the manufacture of mechanical and sulfite paper is commercially available. However, biotechnological products for pitch control in other pulping processes, such as alkaline pulping, are under development. These products include new fungi for the removal of steroids involved in pitch deposit formation in chlorine-free pulps, to be used as a biological pretreatment of wood before pulping. Simultaneously, tailor-made enzymes are being produced using protein-engineering techniques, enabling the specific removal of pitch contaminant compounds from paper pulp.

Biotechnology↗
PubMed2002

A carbon balance method for paper and wood products.

The approach used to track the flow of carbon sequestered in the forest through harvest, processing into products, and final disposition of products is described. The methodology is broadly flexible and applicable to forest-based carbon balance assessments. A carbon balance is computed across all forestland ownerships for the production facility of interest. The balance considers forest uptake, harvest, combustion of fuels, emissions from process steps and losses from product use, disposition and recycling. The method also allows for sensitivity and marginal assessments of a variety of real and hypothetical situations using variable assumptions. Example results for a vertically integrated pulp and paper mill are presented. Results suggest that integrated forest products facilities drawing their raw material from sustainably managed forests can achieve a net positive carbon balance over the product cycle. The amount of net carbon sequestration attributable to such facilities depends upon a number of factors. The most critical of these include net forest growth, the method for allocating the growth in forest carbon among all of those harvesting from the drain area of a given facility, and the use and disposal patterns for the paper or wood products manufactured.

Carbon↗
PubMed2000

Synthesis and characterization of catalysts produced from paper mill sludge. I. Determination Of NOx removal capability.

Characteristics and catalytic properties of a series of carbon-based catalysts (CBCs) produced from paper mill sludge were evaluated. The major processes involved in the production of the catalysts were chemical activation, impregnation, pyrolysis, and post pyrolysis rinsing. The porous structure, catalytic activity and thermostability of the catalysts were tailored during the production stage by introducing hetero-atoms (zinc chloride, and ferric nitrate) in the carbon structure. Characterization of the produced CBCs included determination of the surface area, pore size, and pore size distribution (PSD) from standard N2-adsorption isotherm data. The extent of graphitization and the presence of metal crystals were identified from X-ray diffraction (XRD). The limit of the catalyst gasification was estimated from thermogravimetric analysis (TGA) conducted in an oxidized environment. The NOx reduction capability of the produced catalysts was evaluated in the presence of carbon monoxide using a fixed bed reactor. The reaction temperature ranged from 300 to 500 degrees C. It was shown that paper mill sludge is an excellent precursor for the production of CBCs with NOx removal capability of 66-94%. The catalytic capability of the produced CBCs varied according to the method of production, catalyst surface properties (surface area, pore structure, PSD), metal composition and reaction temperature. The highest NOx removal capacity was observed for the catalytic reactions carried out at 400 degrees C. The mesoporous catalyst produced with a Zn:Fe molar ratio of 1:0.5 exhibited the maximum NOx removal catalytic activity of 94%.

Carbon↗
PubMed2001

Waste-to-energy plant for paper industry sludges disposal: technical-economic study.

In this work, a detailed technical-economic analysis of a fluidized bed based waste-to-energy system for disposal of paper manufacturing sludges has been carried out. Specific reference is made to a case study represented by the largest plant in Italy producing recycled paper, with a daily sludge output of about 52t. The adopted plant has been sized for a nominal capacity of 140t per day also allowing the progressive elimination of sludges accumulated in a previously utilized landfill, giving a nominal electrical power output of 3.5MW. The main plant sections have been described and the adopted technical solutions have been outlined. A detailed process and equipment characterization has been carried out leading to a thorough evaluation of capital investment, operating costs and revenues. A differential analysis has been performed with respect to the alternative solution represented by the disposal of untreated sludges in an external landfill in order to highlight the savings obtainable. The economic profitability of the investment has been evaluated regarding several performance indices. The economic evaluation has been completed by a sensitivity and risk analysis in order to assess the effects of uncertainties in the economically significant parameters. Adopting most probable values, the savings obtained with the considered waste-to-energy system are evaluated in the 15--20 million Euro range during the estimated plant life of 15 years with a foreseen pay back time of 4 years. Moreover, many environmental benefits result such as the remediation of existing landfill, the avoidance of new landfills opening and very low air pollutants emissions.

Capital Financing↗
PubMed2001

Gas chromatographic-mass spectrometric screening for organic acidemias using dried urine filter paper: determination of alpha-ketoacids.

There are several organic acid disorders that require information on alpha-ketoacids, such as maple syrup urine disease or alpha-ketoadipic acidemia. The recovery, stability and diagnostic availability of alpha-ketoacids in dried urine filter paper analyzed by GC-MS with oxime-trimethylsilyl derivatization was studied for organic acidemia screening. The recovery of all nine types of alpha-ketoacids tested, but for phenylpyruvate, 2-ketoadipate, and p-OH-phenylpyruvate, from filter paper samples was acceptable. The stability of pyruvate, branched-chain alpha-ketoacids, alpha-ketoadipate and alpha-ketoglutarate was stable for at least 28 days, although some alpha-ketoacids such as succinylacetone were unstable. It indicated it was difficult to diagnose only tyrosinemia type 1 among nine specimens from organic acidemia patients tested. The method could be applied to global organic acidemia screening.

Acids↗
PubMed2001

Diagnosis of inborn errors of metabolism using filter paper urine, urease treatment, isotope dilution and gas chromatography-mass spectrometry.

This review will be concerned primarily with a practical yet comprehensive diagnostic procedure for the diagnosis or even mass screening of a variety of metabolic disorders. This rapid, highly sensitive procedure offers possibilities for clinical chemistry laboratories to extend their diagnostic capacity to new areas of metabolic disorders. The diagnostic procedure consists of the use of urine or filter paper urine, preincubation of urine with urease, stable isotope dilution, and gas chromatography-mass spectrometry. Sample preparation from urine or filter paper urine, creatinine determination, stable isotope-labeled compounds used, and GC-MS measurement conditions are described. Not only organic acids or polar ones but also amino acids, sugars, polyols, purines, pyrimidines and other compounds are simultaneously analyzed and quantified. In this review, a pilot study for screening of 22 target diseases in newborns we are conducting in Japan is described. A neonate with presymptomatic propionic acidemia was detected among 10,000 neonates in the pilot study. The metabolic profiles of patients with ornithine carbamoyl transferase deficiency, fructose-1,6-bisphosphatase deficiency or succinic semialdehyde dehydrogenase deficiency obtained by this method are presented as examples. They were compared to those obtained by the conventional solvent extraction methods or by the tandem mass spectrometric method currently done with dried filter blood spots. The highly sensitive, specific and comprehensive features of our procedure are also demonstrated by its use in establishing the chemical diagnosis of pyrimidine degradation defects in order to prevent side effects of pyrimidine analogs such as 5-flurouracil, and the differential diagnosis of three types of homocystinuria, orotic aciduria, uraciluria and other urea cycle disorders. Evaluation of the effects of liver transplantation or nutritional conditions such as folate deficiency in patients with inborn errors of metabolism is also described.

Gas Chromatography-Mass Spectrometry↗
PubMed2001

Drug contamination of US paper currency.

It is known that US paper currency in the general circulation is contaminated with cocaine. Several mechanisms have been offered to explain this finding, including contamination due to handling during drug deals and the use of rolled up bills for snorting. Drug is then transferred from one contaminated bill to others during counting in financial institutions. The possibility of contamination of currency with other drugs has not been reported. In this study, the author reports the analysis of 10 randomly collected US$ 1 bills from five cities, for cocaine, heroin, 6-acetylmorphine (6-AM), morphine, codeine, methamphetamine, amphetamine and phencyclidine (PCP). Bills were immersed in acetonitrile for 2h prior to extraction and GC-MS analysis. Results showed that 92% of the bills were positive for cocaine with a mean amount of 28.75+/-139.07 microg per bill, a median of 1.37 microg per bill, and a range of 0.01-922.72 microg per bill. Heroin was detected in seven bills in amounts ranging from 0.03 to 168.50 microg per bill: 6-AM and morphine were detected in three bills; methamphetamine and amphetamine in three and one bills, respectively, and PCP was detected in two bills in amounts of 0.78 and 1.87 microg per bill. Codeine was not detected in any of the US$ 1 bills analyzed. This study demonstrated that although paper currency was most often contaminated with cocaine, other drugs of abuse may be detected in bills.

Chromatography, High Pressure Liquid↗
PubMed1999

Heat trapped under paper and plastic ophthalmic drapes during eye surgery using local anesthesia.

PURPOSE: To assess whether heat trapped under ophthalmic drapes is responsible for patient reports of being hot during cataract surgery using local anesthesia. SETTING: Departments of Anaesthesia and Intensive Care Medicine and of Ophthalmology and Optometry, Innsbruck University Hospital, Innsbruck, Austria. METHODS: In a prospective, randomized, single-blind study, the temperature in the ambient air under 2 types of paper drapes (Group A: Barrier Ophthalmology Drape, Johnson & Johnson; Group B: Steri Drape 1062, 3M) and a plastic drape (Group C: cotton drape + Steri Drape 1024, 3M) was measured for 25 minutes in 60 patients having cataract surgery under local anesthesia. RESULTS: Three minutes after the patient's head was draped, the mean temperature under the drape began to increase significantly: Group A, 25.7 degrees C +/- 0.3 degree C (SD) to 29.17 degrees C +/- 0.9 degree C (P < or = .001); Group B, 25.87 degrees C +/- 0.4 degree C to 29.41 degrees C +/- 0.9 degree C (P < or = .001); Group C, 25.8 degrees C +/- 0.35 degree C to 29.4 degrees C +/- 0.6 degree C (P < or = .001). It continued to increase in all groups as the operation continued. No significant differences in temperature were observed among the 3 drape types studied. Subjective thermal discomfort was reported by 35% to 40% of patients. CONCLUSION: Paper drapes did not cause less heat from being trapped than the plastic drape. Trapped heat may impair the comfort of patients having eye surgery under local anesthesia.

Anesthesia, Local↗
PubMed2002

Removal of polychlorinated biphenyls from capacitors and pressure-sensitive paper by vacuum thermal recycling.

This paper describes a new vacuum thermal recycling (VTR) method for treating discarded polychlorinated biphenyls (PCB)-contaminated capacitors and pressure-sensitive paper. Based on results demonstrating an exceptionally high PCB separation efficiency and recovery ratio from capacitors containing high-concentration PCBs, i.e. > 99.9%, respectively, the presented VTR method is verified to effectively remove PCBs. In addition, associated safety aspects of the employed procedure were confirmed.

Conservation of Natural Resources↗
PubMed2003

Waste paper and clinoptilolite as a bulking material with dewatered anaerobically stabilized primary sewage sludge (DASPSS) for compost production.

Environmental problems associated with sewage sludge disposal have prompted strict legislative actions over the past few years. At the same time, the upgrading and expansion of wastewater treatment plants have greatly increased the volume of sludge generated. The major limitation of land application of sewage sludge compost is the potential for high heavy metal content in relation to the metal content of the original sludge. Composting of sewage sludge with natural zeolite (clinoptilolite) can enhance its quality and suitability for agricultural use. However, the dewatered anaerobically stabilized primary sewage sludge (DASPSS) contained a low concentration of humic substances (almost 2%), and the addition of the waste paper was necessary in order to produce a good soil conditioner with high concentrations of humics. The final results showed that the compost produced from DASPSS and 40-50% w/w of waste paper was a good soil fertilizer. Finally, in order to estimate the metal leachability of the final compost product, the generalized acid neutralization Capacity (GANC) procedure was used, and it was found that by increasing the leachate pH, the heavy metal concentration decreased. The application of the sequential chemical extraction indicated that metals were bound to the residual fraction characterized as a stabilize fractions.

Bacteria, Anaerobic↗
PubMed2002

Ethanol-acetone pulping of wheat straw. Influence of the cooking and the beating of the pulps on the properties of the resulting paper sheets.

The influence of independent variables in the pulping of wheat straw by use of an ethanol-acetone-water mixture [processing temperature and time, ethanol/(ethanol + acetone) value and (ethanol + acetone)/(ethanol + acetone + water) value] and of the number of PFI beating revolutions to which the pulp was subjected, on the properties of the resulting pulp (yield and Shopper-Riegler index) and of the paper sheets obtained from it (breaking length, stretch, burst index and tear index) was examined. By using a central composite factor design and the BMDP software suite, equations that relate each dependent variable to the different independent variables were obtained that reproduced the experimental results for the dependent variables with errors less than 30% at temperatures, times, ethanol/(ethanol + acetone) value, (ethanol + acetone)/(ethanol + acetone + water) value and numbers of PFI beating revolutions in the ranges 140-180 degrees C, 60-120 min, 25-75%, 35-75% and 0-1750, respectively. Using values of the independent variables over the variation ranges considered provided the following optimum values of the dependent variables: 78.17% (yield), 15.21 degrees SR (Shopper-Riegler index), 5265 m (breaking length), 1.94% (stretch), 2.53 kN/g (burst index) and 4.26 mN m2/g (tear index). Obtaining reasonably good paper sheets (with properties that differed by less than 15% from their optimum values except for the burst index, which was 28% lower) entailed using a temperature of 180 degrees C, an ethanol/(ethanol + acetone) value of 50%, an (ethanol + acetone)/(ethanol + acetone + water) value of 75%, a processing time of 60 min and a number of PFI beating revolutions of 1750. The yield was 32% lower under these conditions, however. A comparison of the results provided by ethanol, acetone and ethanol-acetone pulping revealed that the second and third process-which provided an increased yield were the best choices. On the other hand, if the pulp is to be refined, ethanol pulping is the process of choice.

Acetone↗
PubMed2002

Effectiveness of algae in the treatment of a wood-based pulp and paper industry wastewater.

In this study, the ability of algae to treat a wood-based pulp and paper industry wastewater was investigated. Tests were performed in batch reactors seeded with a mixed culture of algae. Under different lighting and initial wastewater strength conditions, changes in COD, AOX and color contents of reactors were followed with time. Algae were found to remove up to 58% of COD, 84% of color and 80% of AOX from pulp and paper industry wastewaters. No remarkable differences were observed in COD and color when light intensity and wastewater strength were changed, while AOX removals were strongly affected. Algal species identification studies revealed that some green algae (Chlorella) and diatom species were dominant in the treatment. The study also showed that algae grew mixotrophically, while the main mechanism of color and organics removal from pulping effluents was partly metabolism and partly metabolic conversion of colored and chlorinated molecules to non-colored and non-chlorinated molecules. Adsorption onto algal biomass was not so effective.

Biodegradation, Environmental↗
PubMed2003

TCF bleaching of wheat straw pulp using ozone and xylanase. Part A: paper quality assessment.

The XOAZRP TCF sequence was applied to bleach wheat straw pulp. Following each bleaching stage, the properties of the pulp (viz. kappa number, standard viscosity, borohydride viscosity and brightness) and of the resulting effluents were determined. The performance of the reagents was analyzed through the studies of xylanase treatment and crystallinity and scanning electron microscopy of the pulps. Finally, the pulp was refined at 1000 revolutions in a PFI mill and the mechanical properties of the resulting paper were determined and compared with those of paper from a eucalyptus pulp. Despite its shortcomings, wheat straw pulp can be effectively bleached with the proposed TCF sequence.

Conservation of Natural Resources↗
PubMed2004

Mixed acid fermentation of paper fines and industrial biosludge.

This paper uses countercurrent fermentation to anaerobically convert paper fines and industrial biosludge to carboxylate salts using a mixed culture of acid-forming microorganisms. Using the MixAlco process, the carboxylate salts can be thermally converted to ketones and hydrogenated into mixed alcohol fuels. Continuum particle distribution modeling (CPDM) correlated batch fermentation data to countercurrent fermentation data, allowing the prediction of product concentrations and conversions over a wide range of solid loading rates and liquid residence times. For 80% paper/20% biosludge, the predicted product concentrations agreed with the data within 7.7%. The predicted conversion agreed with the actual conversion within 27.8%. By correcting for varying selectivity, the predicted conversion agreed with the actual conversions within 15.2%. For 40% paper/60% biosludge, the predicted product concentrations agreed with the data within 9.6%. The predicted conversion agreed with the actual conversion within 28.3%. By correcting for varying selectivity, the predicted conversion agreed with the actual conversions within 15.4%. For both the 80/20 and 40/60 cases, CPDM predicts that 90% conversion is possible with a 20 g/l product concentration, 300 g/l substrate concentration, 16 day liquid residence time, and 2.5 g/(ld) solids loading rate. Before proceeding to an industrial plant, these predictions must be verified in a pilot plant.

Acids↗
PubMed2002

Transport of 125I and 36Cl across an anion-exchange paper membrane.

The membrane characteristics controlling 125I and 36Cl transport across anion-exchange paper membranes are examined using three different paper membranes treated with different anion exchange groups: a trimethylhydroxypropylamino group, a diethylaminoethyl group, and a 50% quaternary diethylaminoethyl group. The membrane permeability for 125I is higher than that for 36Cl in all cases. Treatment with trimethylhydroxypropylamino group improves the 125I diffusion process, and the use of 50% quaternary diethylaminoethyl group improves the 125I solution/membrane distribution process.

Chlorine↗
PubMed1999

A paper chromatographic technique for quantitative evaluation of hydrolysed and ionic components in 201Tl radiopharmaceuticals.

A reported paper chromatographic technique has been extended to delineate the hydrolysed components in 201Tl radiopharmaceuticals for the determination of radiochemical purity. Detailed radiochemical purity analysis of 201TlCl has been demonstrated using mini paper chromatographic systems. The technique is also useful in evaluation of the radiochemical purity of 67Ga and 111In radiopharmaceuticals.

Chromatography, Paper↗
PubMed2006

[Conservation of Malassezia strains in blotting paper].

Reference strains belonging to the genus Malassezia were analyzed to evaluate, by comparison, different preservation systems such us subculture, freezing at -80 degrees C in glycerol, and blotting paper-disc conservation. The viability, phenotypic and genotypic characteristics of the strains used in this study was evaluated. The blotting paper method was found to be advantageous to preserve Malassezia spp strains due to both, its simple implementation in the laboratory and its efficiency.

Cryopreservation↗
PubMedDate not supplied

The use of acid phosphatase test papers for DNA profiling.

The acid phosphatase (AP) test is a routine assay used to screen casework items for the possible presence of semen. This colour test is carried out on filter paper which is retained after testing. Two-year-old AP test papers were found to contain sufficient DNA for short tandem repeat (STR) profiling. Prior to polymerase chain reaction (PCR) amplification, the DNA was preferentially separated into sperm depleted and sperm enriched cell fractions. The implication of these findings for past and present cases is discussed.

Acid Phosphatase↗