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1. TIMING OF EXPOSURE TO A PULP AND PAPER EFFLUENT INFLUENCES THE MANIFESTATION OF REPRODUCTIVE EFFECTS IN RAINBOW TROUT.

Author

Van den Heuvel, Michael R. and Ellis, Rosanne J.

Subjects
*RAINBOW trout, *ESTRADIOL, *STEROIDS, *TESTOSTERONE, *BIOCHEMISTRY
Abstract

Rainbow trout were exposed to a secondary treated, thermomechanical/bleached kraft pulp and paper effluent in 12,000-L, flow-through exposure tanks at an environmental research facility located at a pulp and paper mill in Kawerau, New Zealand. Trout (age, 21 years) were obtained from a local hatchery and exposed either to upstream river water or a nominal concentration of 12% (v/v) effluent diluted in upstream river water. Three treatment groups were used: Effluent exposure that started approximately three months before gonadal growth (eight-month total exposure), effluent exposure that started approximately halfway through gonadal development (two-month total exposure), and trout exposed to reference water alone for the total duration of the experiment. Trout were sacrificed just before spawning; exposure, growth, and reproductive endpoints were assessed during and at the termination of the experiment. Reduction in growth was observed in both sexes in the eight-month treatment group relative to the river water reference treatment group. No differences were observed in condition factor or liver size in either treatment. Females in the eight-month exposure group also had significantly lower ovary weight. The two-month exposure group showed no differences from the reference group in growth or somatic indices. Estradiol and testosterone were reduced in blood samples taken from the eight-month exposure group by four months into the experiment as compared to the reference treatment. Steroid and vitellogenin levels in individual female trout from this treatment were significantly correlated with gonadosomatic indices (GSI) measured at the termination of the experiment. The GSI was not correlated strongly or consistently with pregnenolone, nor were any treatment-related preg-nenolone differences observed, indicating that the steroid hormone reductions likely were not related to cholesterol side-chain cleavage. Male trout showed significant induction of vitellogenin and... [ABSTRACT FROM AUTHOR]

Published
2002
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2. Humidity Sensors Printed on Recycled Paper and Cardboard

Author

Matej Pivar, Tadeja Muck, Janez Trontelj, Matija Mraović, and Anton Pleteršek

Subjects
Paper, Engineering, Silver, Capacitive sensing, lcsh:Chemical technology, Electric Capacitance, Biochemistry, Capacitance, Article, Analytical Chemistry, smart labels, pulp, Conductive ink, lcsh:TP1-1185, Relative humidity, ComputerSystemsOrganization_SPECIAL-PURPOSEANDAPPLICATION-BASEDSYSTEMS, Recycling, Electrical and Electronic Engineering, Instrumentation, passive tag, business.industry, UHF data logger SL900A, Electrical engineering, Humidity, cardboard, Equipment Design, Atomic and Molecular Physics, and Optics, screen-printed sensors, printed electronics, radio frequency identification (RFID), Radio Frequency Identification Device, Printed electronics, visual_art, Screen printing, visual_art.visual_art_medium, Optoelectronics, Printing, business
Abstract

Research, design, fabrication and results of various screen printed capacitive humidity sensors is presented in this paper. Two types of capacitive humidity sensors have been designed and fabricated via screen printing on recycled paper and cardboard, obtained from the regional paper and cardboard industry. As printing ink, commercially available silver nanoparticle-based conductive ink was used. A considerable amount of work has been devoted to the humidity measurement methods using paper as a dielectric material. Performances of different structures have been tested in a humidity chamber. Relative humidity in the chamber was varied in the range of 35%–80% relative humidity (RH) at a constant temperature of 23 °C. Parameters of interest were capacitance and conductance of each sensor material, as well as long term behaviour. Process reversibility has also been considered. The results obtained show a mainly logarithmic response of the paper sensors, with the only exception being cardboard-based sensors. Recycled paper-based sensors exhibit a change in value of three orders of magnitude, whereas cardboard-based sensors have a change in value of few 10s over the entire scope of relative humidity range (RH 35%–90%). Two different types of capacitor sensors have been investigated: lateral (comb) type sensors and modified, perforated flat plate type sensors. The objective of the present work was to identify the most important factors affecting the material performances with humidity, and to contribute to the development of a sensor system supported with a Radio Frequency Identification (RFID) chip directly on the material, for use in smart packaging applications. Therefore, the authors built a passive and a battery-supported wireless module based on SL900A smart sensory tag’s IC to achieve UHF-RFID functionality with data logging capability.

Published
2014

3. Enzymatic upgrade of old paperboard containers

Author

Helena Pala, Manuel Mota, Francisco M. Gama, M.A.N.D.A. Lemos, and Universidade do Minho

Subjects
0106 biological sciences, Paper, Enzyme action, business.product_category, Bioengineering, 02 engineering and technology, Cellulase, Pulp, engineering.material, 01 natural sciences, Applied Microbiology and Biotechnology, Biochemistry, chemistry.chemical_compound, 010608 biotechnology, Pulp and paper, Cellulose, chemistry.chemical_classification, Paperboard, Physical properties, Science & Technology, biology, Chemistry, Pulp (paper), 021001 nanoscience & nanotechnology, Pulp and paper industry, Carton, Enzyme, visual_art, engineering, biology.protein, visual_art.visual_art_medium, Drainage, Valorisation, 0210 nano-technology, business, Cellulose binding-domains, Biotechnology
Abstract

The use of enzymes in secondary fiber (old paperboard containers) upgrading was investigated. The following aspects were analyzed: (i) the effect of several enzymes and (non-hydrolytic) cellulose-binding domains on the pulp and paper properties; (ii) factors influencing enzymatic treatment of secondary fiber: enzyme dosage and reaction time; and (iii) enzyme action on fractions with different fiber-length. In general, all the tested enzymatic preparations were able to improve the pulp drainability. In most cases this improvement was obtained at the expense of paper strength. The use of cellulose-binding domains allowed for the simultaneous increase in drainability and strength properties.

Published
2001