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Significance: Optical fluorescence spectroscopy technique has been explored extensively to quantify both glucose uptake and mitochondrial metabolism with proper fluorescent probes in small tumor models in vivo. However, it remains a great challenge to rapidly quantify the intrinsic metabolic fluorophores from the optically measured fluorescence spectra that contain significant distortions due to tissue absorption and scattering. Aim: To enable rapid spectral data processing and quantify the in vivo metabolic parameters in real-time, we present an empirical ratio-metric method for rapid fluorescence spectra attenuation correction with high accuracy. Approach: A first-order approximation of intrinsic fluorescence spectra can be obtained by dividing the fluorescence spectra by diffuse reflectance spectra with some variable powers. We further developed this approximation for rapid extraction of intrinsic key metabolic probes (2-NBDG for glucose uptake and TMRE for mitochondrial function) by dividing the distorted fluorescence spectra by diffuse reflectance intensities recorded at excitation and emission peak with a pair of system-dependent powers. Tissue-mimicking phantom studies were conducted to evaluate the method. Results: The tissue-mimicking phantom studies demonstrated that our empirical method could quantify the key intrinsic metabolic probes in near real-time with an average percent error of ∼5%. Conclusions: An empirical method was demonstrated for rapid quantification of key metabolic probes from fluorescence spectra measured on a tissue-mimicking turbid medium. The proposed method will potentially facilitate real-time monitoring of key metabolic parameters of tumor models in vivo using optical spectroscopy, which will significantly advance translational cancer research.

Significance: Recent generation of bioengineered human skin allowed the efficient treatment of patients with severe skin defects. However, the optical and biomechanical properties of these models are not known. Aim: Three models of bioengineered human skin based on fibrin-agarose biomaterials (acellular, dermal skin substitutes, and complete dermoepidermal skin substitutes) were generated and analyzed. Approach: Optical and biomechanical properties of these artificial human skin substitutes were investigated using the inverse adding-doubling method and tensile tests, respectively. Results: The analysis of the optical properties revealed that the model that most resembled the optical behavior of the native human skin in terms of absorption and scattering properties was the dermoepidermal human skin substitutes after 7 to 14 days in culture. The time-course evaluation of the biomechanical parameters showed that the dermoepidermal substitutes displayed significant higher values than acellular and dermal skin substitutes for all parameters analyzed and did not differ from the control skin for traction deformation, stress, and strain at fracture break. Conclusions: We demonstrate the crucial role of the cells from a physical point of view, confirming that a bioengineered dermoepidermal human skin substitute based on fibrin-agarose biomaterials is able to fulfill the minimal requirements for skin transplants for future clinical use at early stages of in vitro development., Ministry of Science, Innovation and Universities of Spain PGC2018-101904-A-I0, Instituto de Salud Carlos III (ISCIII), Ministry of Science, Innovation and Universities, through AES 2017 AC17/00013, Instituto de Salud Carlos III (ISCIII), Ministry of Science, Innovation and Universities within EuroNanoMed framework, EU AC17/00013, University of Granada A.TEP.280.UGR18, Junta de Andalucía PE-0395-2019, Fundación Benéfica Anticancer San Francisco Javier y Santa Cándida, Granada, Spain, OTRI.35A-07

Baigiamajame magistro projekte nagrinėjama nekreidinio popieriaus savybės, reakcija į išorinius dirgiklius. Nagrinėjama skirtingos gramatūros ir skirtingų purumų popieriai. Apskaičiuota technologinė įmonės gamybos apimčių dalis. Analizuojamas žaliavų kiekis, reikalingas produkcijai pagaminti., The master's thesis examines the properties of non-linear paper, its reaction to external stimuli. Different grammar and different types of paper‘s bulk are analyzed. Technological part of the company's production volume is calculated. The amount of raw materials needed to produce the product is analyzed.

Introduction: Printing inks oil selection is related to the desired nature of the varnish in the ink production. Petroleum-derived mineral oils and vegetable oils can be used in offset inks. Methods: In this study, the behaviors of vegetable- and mineral oil-based inks on uncoated and coated paper surfaces were investigated in terms of printability. Solid tone test prints were done with offset printing of these inks. Print gloss of the printed samples was measured and a light fastness test was implemented on these samples in order to determine the resistance to fading. Absorption behavior and contact angles of the ink-printed films on the test papers were measured with the sessile water drop method depending on time, and surface energies were calculated. Results: On both paper types, linseed–soybean oil-based vegetable ink gave the highest brightness value. The lowest print gloss results on the paper were obtained from soybean oil-based inks. The lowest color change was recorded with mineral oil-based inks on gloss-coated papers. According to the ink-film–surface relation, when the contact angle is high, surface energy decreases and the absorbency of the ink-film is lower. Conclusions: In this study, the behaviors of vegetable- and mineral oil-based inks on different paper surfaces, and the effect on the quality of printability as well as differences, have been evaluated, taking environmental and health factors into consideration.

Dental root canal treatment is required when dental caries progress to infection of the dental pulp. A major goal of this treatment is to provide complete decontamination of the dental root canal system. However, the morphology of dental root canal systems is complex, and many human dental roots have inaccessible areas. In addition, dental reinfection is fairly common. In conventional treatment, a cotton pellet and paper point made from plant cellulose is used to dry and sterilize the dental root canal. Such sterilization requires a treatment material with high absorbency to remove any residue, the ability to improve the efficacy of intracanal medication and high biocompatibility. Bacterial cellulose (BC) is produced by certain strains of bacteria. In this study, we developed BC in a pointed form and evaluated its applicability as a novel material for dental canal treatment with regard to solution absorption, expansion, tensile strength, drug release and biocompatibility. We found that BC has excellent material and biological characteristics compared with conventional materials, such as paper points (plant cellulose). BC showed noticeably higher absorption and expansion than paper points, and maintained a high tensile strength even when wet. The cumulative release of a model drug was significantly greater from BC than from paper points, and BC showed greater compatibility than paper points. Taken together, BC has great potential for use in dental root canal treatment.

Papermill sludge (PMS) is generated during the wastewater treatment process of paper production. Its handling and disposal techniques are of great concern for the environment. It can be landfilled as a waste, or it can be recycled and converted into useful products of high value. It has a very promising application as an absorbing agent for the cleaning of water surfaces polluted with hydrophobic substances (vegetable, synthetic and mineral oils, animal fats, fuels, organic chemicals and even coal dust). Here, we present the pretreatment procedure (hydrophobation, mechanical and thermal treatments) of PMS that produces a lightweight absorbent material (HAWSC - high efficiency absorbent for water surface cleaning), which floats on the water surface and binds hydrophobic pollutants with considerably higher efficiency than commercially available mineral and synthetic absorbents. After its application, it can be incinerated, due to its high caloric value, to produce energy. The incineration residues can then be formed into granules that can be used as an efficient absorbent for fluids spilled onto solid surfaces.

At present, there are many methods for Cr(VI) concentration determination in diluted samples, however, these methods have their own inherent drawbacks, such as long response time, complicated pretreatment, expensive equipment etc. In this paper, a paper-based test strip method specific for determination of diluted Cr(VI) samples was developed. In this method, Aliquat 336, as an anion exchanger was loaded into filter paper to form a test strip. This test strip was used to pre-concentrate Cr(VI) when contacting with the diluted Cr(VI)-containing solution. The Cr(VI)-containing test strip was then immersed into a diphenylcarbazide (DPC) solution (a color forming solution), and the color intensity was correlated to the Cr(VI) concentration. The detection range of the present method was found to be 0.02–1.50 mg/L. The results also showed that the method gave a high selectivity for Cr(VI) in the diluted samples to be tested. The method was applied to synthesized samples and the results, which were compared to those from a reference method, showed that the developed method is an effective, reliable way for Cr(VI) determination in diluted samples.

The optical properties and degradation of fir wood treated by different inorganic salts, which are components of waterborne wood preservatives, were studied before and after wet-thermal accelerated ageing (T=85 degrees C, RH=65%, for 30 days) using UV-Vis diffuse reflectance spectroscopy. The colour of all impregnated samples was due to the same chromophoric structures, thus revealing that the primary reactions leading to colour changes are essentially very similar. These chemically treated as well as standard (non-treated, unaged) and reference (treated only with distilled water, unaged/aged) samples have a significant absorption band at 358 nm, along with a shoulder near 265 nm of various intensity. The broad band at higher wavelength is attributed to the chromophoric structures derived especially from lignin, i.e. quinones, stilbenes, charge transfer complexes causing a bathochromic shift and other conjugated carbonyl structures. Coniferaldehyde is also a major contributor to this absorption. The band at 265 nm belongs to chromophores arising predominantly from carbohydrate degradation products, i.e. furan derivatives, quinone-type derivatives, catechol structures. Catechol structures (colourless) form coloured complexes with transition metal cations (Cu2+, Fe3+) or are oxidized to form highly coloured benzoquinone structures. Alkaline solutions of borax cause the reduction of conjugated and non-conjugated carbonyls and the degradation of coniferaldehyde. Generally, after ageing, the samples show higher absorptions in the visible region of the spectra in comparison. with the unaged ones, which explains their yellowing and loss of brightness after the action of elevated temperature and moisture.

The technical properties of three layered cement-bonded boards (CBBs) made from wastepaper and sawdust were investigated. The CBBs were produced at three density levels of 1000, 1200 and 1300 kg/m3 and at four cement/particle ratios of 2.0:1, 2.5:1, 3.0:1 and 3.5:1 on a weight to weight basis. The technical properties evaluated were modulus of rupture (MOR), modulus of elasticity (MOE), water absorption (WA) and thickness swelling (TS). The MOR values ranged from 4.85 to 11.69 MPa and MOE values ranged from 2.80 to 5.57 GPa. The mean values of WA and TS after 24 h of water soaking of the CBBs ranged from 18.18% to 40.49% and 3.55% to 12.13%, respectively. MOR and MOE of the CBBs increased with increase in board density, but MOR decreased with the increase in cement/particle ratio. On the other hand, WA and TS decreased with increase in board density and cement/particle ratio. CBBs produced from wastepaper and sawdust at cement/particle ratios of 3.0:1 and 3.5:1 are suitable for building construction such as paneling, ceiling and partitioning.

Dairy cattle barns are a major source of NH3 emissions to the atmosphere. Previous studies have shown that the bedding material used in the barn can influence the magnitude of NH3 emissions, but little is known about which bedding characteristics are important in this respect. The aims of this study were to assess, at a laboratory scale, the relative importance of the chemical [pH, cation exchange capacity (CEC), C:N] and physical (urine absorbance capacity, bulk density) characteristics of 5 bedding materials (chopped wheat straw, sand, pine shavings, chopped newspaper, chopped corn stalks, and recycled manure solids) on NH3 emissions from dairy cattle urine. Recycled manure solids were the most absorbent of the bedding types (4.2 g of urine/g of bedding), and sand was the least (0.3 g of urine/g of bedding). When beddings were soaked in urine to their absorbance capacities, NH3 emissions over 48 h (expressed as a proportion of the urine N absorbed) were not significantly different among bedding types, despite differences in initial bedding pH, CEC, and C:N. When equal volumes of urine were applied to equal depths of dry bedding, NH3 emissions over 48 h were significantly less from sand and pine shavings (23 and 42% of applied urine N, respectively) than from chopped newspaper, chopped corn stalks, and recycled manure solids (62, 68, and 65% of applied urine N, respectively), whereas emissions from chopped wheat straw (55% applied urine N) only differed significantly from that from sand. Differences in the chemical characteristics of the beddings did not explain differences in emission; NH3 emissions increased linearly with CEC contrary to expectations, and there was no significant relationship with initial bedding pH. The physical characteristics of bedding materials were of more importance, as NH3 emissions increased linearly with absorbance capacity and decreased as the bulk density of the packed beddings increased.

Photodegradation of lignin is one of the major postprocessing problems in paper production, as this renders yellowing of the paper and reduced paper quality. In this study, we have explored the photochemical properties of substituted stilbene derivatives believed to be key chromophores in the photodegradation of lignin derived from cinnamyl alcohol. In particular, the present work focuses on the computation of UV/vis electronic absorption spectra for different methoxylated stilbenes and their proposed photodegradation products. All calculations were performed using the time-dependent formalism of density functional theory (TD-DFT) and the B3LYP hybrid functional. It is concluded that the methodology employed is capable of reproducing not only the overall spectra, but also subtle features owing to the effects of different substitution patterns. For the strongly absorbing first excited singlet state (HOMO --LUMO excitation) of the methoxylated stilbenes, the calculated transition energies are, albeit somewhat fortuitously, in excellent agreement with experimental data. The light-induced yellowing indirectly caused by the presence of stilbenes can be rationalized in terms of the absorption spectra of the resulting photodegraded o-quinones, for which distinct transitions in the 420-500 nm region of the visible spectrum lacking prior to degradation are observed.

The migration of five surrogate contaminants, anthracene, benzophenone, dimethyl phthalate, methyl stearate and pentachlorophenol, from paper and paperboard into water through a polyethylene (PE) coating layer was investigated. Virgin paper and paperboard coated with PE films of 0.012 and 0.030 mm thickness were spiked evenly with standard 1-ml solutions containing 5mg of each surrogate. The spiked papers were placed in contact with the PE coating layer at 10 and 24 degrees C for 21 days. The resulting surrogate migration through the PE layer into 100ml water was measured by an analytical method developed here that used gas chromatography equipped with a flame ionization detector. Non-polar surrogates of anthracene and methyl stearate did not show any significant migration. In the case of the thin layer coating of 0.012 mm, polar water-soluble contaminants of benzophenone, dimethyl phthalate and pentachlorophenol showed an equilibrated or maximized migration after 1 day, even at a refrigerated temperature of 10 degrees C. A thick PE coating of 0.030 mm thickness delayed the progress of contaminant migration, which was also slower at lower temperature. Our results indicate that polyethylene coatings should not be seen as a complete barrier against possible contaminants in paper packaging materials under chilled or ambient conditions. Several variables such as coating thickness, temperature and suspected contaminants need to be considered to control the possible contamination risk from recycled or printed paper.

Xylan from oat spelt and wheat was used as an additive to enhance the dry strength of paper. The absorption of xylan by the cellulose fibers was increased by cationization to different degrees of substitution. Paper hand sheets with different doses of xylan and industrial cationic starch were produced, and the mechanical properties were determined. Absorption measurements of cationic oat spelt xylan on pulp fibers explained the differing influences of low and high cationized xylan addition on paper strength. The addition of cationic oat spelt xylan with a degree of substitution of 0.1 at a 4% dose provided the largest improvement in the tensile-index (67%), burst-index (105%) and tear-index (77%). Compared to cationic starch, cationic oat spelt xylan additives led to similar paper strength values, excepting the tear strength. The structural differences and protein impurities made the wheat xylan unsuitable as a strength additive for paper pulp.

BACKGROUND Carcinoembryonic antigen (CEA) is used as a serum marker to detect and monitor the status of various kinds of malignant tumors. To determine whether CEA might be detected in secretions collected topically from around the nipple area, and whether its secretion might differ in a cancerous versus a noncancerous breast, we developed a simple method for collecting and measuring CEA, using a small cellulose membrane disk and an enzyme immunoassay. METHODS We measured the amount of CEA excreted from the nipple area of 22 healthy control women and 32 women with unilateral breast carcinoma confirmed histologically. Secretions were collected from the nipple area by affixing a small (20 mm diameter) absorbent disk made of nitrocellulose membrane backed with filter paper to that area for 24 hours. Substances absorbed by the membrane were then subjected to an immunoassay for CEA using anti-CEA antibodies. RESULTS In the 22 healthy subjects, a small amount of CEA (0.6 +/- 0.9 units) was secreted from each nipple, which was equally low regardless of the phase of the menstrual cycle. In contrast, 30 of the 32 women with breast carcinoma secreted significantly greater amounts of CEA from the cancerous (16.1 +/- 8.2) than the noncancerous (2.0 +/- 2.2) breast. Such a difference (14.1 +/- 8.0) in CEA excretion was not observed in the healthy controls (0 +/- 0). CONCLUSIONS These findings suggest that such disks may provide a simple and noninvasive method of collecting trace molecules, including CEA, in skin secretions around the nipple to evaluate functional disorders of the mammary glands, particularly breast carcinoma. Additional studies are indicated in larger groups of women with various stages of breast carcinoma as well as with benign breast diseases.

This paper presents the results of an investigation into the use of wastepaper sludge in geopolymer mortar systems for manufacturing construction products. The investigation was driven by the increasing demand for reuse options in paper-recycling industry. Both fresh and hardened geopolymer mortar properties are evaluated for samples incorporating dry wastepaper sludge, and the results indicate potential end-use benefits in building product manufacture. Addition of wastepaper sludge to geopolymer mortar reduces flow properties, primarily due to dry sludge absorbing water from the binder mix. The average 91-day compressive strength of mortar samples incorporating 2.5 wt% and 10 wt% wastepaper sludge respectively retained 92% and 52% of the reference mortar strength. However, contrary to the normal trend of increasing drying shrinkage with increasing paper sludge addition to Portland cement matrices, the corresponding geopolymer drying shrinkage decreased by 34% and 64%. Equally important, the water absorption of hardened geopolymer mortar decreased with increasing paper sludge content at ambient temperatures, providing good prospects of overall potential for wastepaper sludge incorporation in the production of building and masonry elements. The results indicate that, despite its high moisture absorbance due to the organic matter and residual cellulose fibre content, wastepaper sludge appears compatible with geopolymer chemistry, and hence serves as a potential supplementary additive to geopolymer cementitious masonry products.

We describe a latex wet coalescence method for gas-phase immobilization of microorganisms on paper which does not require drying for adhesion. This method reduces drying stresses to the microbes. It is applicable for microorganisms that do not tolerate desiccation stress during latex drying even in the presence of carbohydrates. Small surface area, 10–65 μm thick coatings were generated on chromatography paper strips and placed in the head-space of vertical sealed tubes containing liquid to hydrate the paper. These gas-phase microbial coatings hydrated by liquid in the paper pore space demonstrated absorption or evolution of H2, CO, CO2 or O2. The microbial products produced, ethanol and acetate, diffuse into the hydrated paper pores and accumulate in the liquid at the bottom of the tube. The paper provides hydration to the back side of the coating and also separates the biocatalyst from the products. Coating reactivity was demonstrated for Chlamydomonas reinhardtii CC124, which consumed CO2 and produced 10.2 ± 0.2 mmol O2 m−2 h−1, Rhodopseudomonas palustris CGA009, which consumed acetate and produced 0.47 ± 0.04 mmol H2 m−2 h−1, Clostridium ljungdahlii OTA1, which consumed 6 mmol CO m−2 h−1, and Synechococcus sp. PCC7002, which consumed CO2 and produced 5.00 ± 0.25 mmol O2 m−2 h−1. Coating thickness and microstructure were related to microbe size as determined by digital micrometry, profilometry, and confocal microscopy. The immobilization of different microorganisms in thin adhesive films in the gas phase demonstrates the utility of this method for evaluating genetically optimized microorganisms for gas absorption and gas evolution.

Kubelka i Munk dali su sažeti oblik i pristup s jasnim ciljem ka praktičnim metodama mjerenja. Njihova metoda je bila brzo prihvaćena u papirnoj industriji i danas ima široku primjenu u mjerenju i procjeni obojenja, svjetline i opaciteta pri proizvodnji papira. Unatoč tome navedena metoda posjeduje neke nedostatke i drugi dio članka će pokriti sustave na koje se ne može tako kvalitetno primijeniti (otisnuti i reciklirani papir). Također će biti riječi i o numeričkim modelima (simulacije putanja pojedinačnih fotona) koji se koriste kao nadopuna rezultatima dobivenima K-M metodom. Najčešće korišteni su Monte Carlo simulacijski modeli, GRACE i DORT. Većina informacija u ovom članku preuzeta je iz referenca čiji se popis nalazi na kraju članka i koje je potrebno konzultirati za detaljniju analizu., Kubelka-Munk theory was quickly adapted for use by the papermaking industry and has now been in widespread use for decades in the measurement and prediction of colour, brightness and opacity of paper sheets. Though it remains the most used in practice, it has some disadvantages and the second part of the article will cover a system that is less applicable to the theory itself (an ink-dyed sheet of paper or strongly absorbing media) as well as numerical methods (simulations of individual photon paths) which are used to improve the results obtained by the K-M theory. The most commonly used are Monte Carlo simulation model, GRACE and DORT. Most of the information reported here is taken from the references cited at the end of the article which should be consulted for a more in-depth study.

One of the greatest simplifications of the transfer equation is where all incident and scattered light is assumed to be perfectly diffuse, only two opposite directions of light transport are considered, and the light intensity is assumed to vary along one axis only. Such two-flux approximations have been presented by many authors, starting with a paper by Schuster [1]. One of the most famous two-flux approximations is the approximation presented by Kubelka and Munk[2] in 1931 and further developed by Kubelka[3, 4]. Kubelka and Munk gave a comprehensive formulation and a treatment with a clear aim towards practical methods of measurement. It was quickly adapted for use by the papermaking industry[5-8] and has now been in widespread use for decades in the measurement and prediction of colour, brightness and opacity of paper sheets. Most of the information reported here is taken from the references cited at the end of the article which should be consulted for a more in-depth study.

One of the greatest simplifications of the transfer equation is where all incident and scattered light is assumed to be perfectly diffuse, only two opposite directions of light transport are considered, and the light intensity is assumed to vary along one axis only. Such two-flux approximations have been presented by many authors, starting with a paper by Schuster [1]. One of the most famous two-flux approximations is the approximation presented by Kubelka and Munk [2] in 1931 and further developed by Kubelka [3,4]. Kubelka and Munk gave a comprehensive formulation and a treatment with a clear aim towards practical methods of measurement. It was quickly adapted for use by the papermaking industry [5-8] and has now been in widespread use for decades in the measurement and prediction of colour, brightness and opacity of paper sheets. Most of the information reported here is taken from the references cited at the end of the article which should be consulted for a more in-depth study., Jedno od najvećih pojednostavnjenja jednadžbe transfera pretpostavlja: upadno i raspršeno zračenje je savršeno difuzno, promatraju se samo dva suprotna smjera prijenosa svjetlosti, i intenzitet svjetlosti se mijenja samo duž jedne osi. Takvu aprokimaciju dva smjera prijenosa svjetlosi započeo je Schuster [1], a nastavili su Kubelka i Munk [2] 1931. a model je dalje usavršio Kubelka [3-4]. Kubelka i Munk su dali sažeti oblik i pristup s jasnim ciljem ka praktičnim metodama mjerenja. Ta metoda je bila brzo prihvaćena u papirnoj industriji [5-8] i danas ima široku piimjenu u mjerenju i procjeni obojenja, svjetline i opaciteta pri proizvodnji papira. Većina informacija u ovom članku preuzeta je iz referenca čiji se popis nalazi na kraju članka i koje je potrebno konzultirati za detaljniju analizu.

This paper presents results of an investigation into the use of de-inking sludge from a paper recycling mill as feedstock material in the manufacture of cement mortar products, including masonry blocks and mortar renders. Both physical and mechanical properties of mortar specimens containing various amounts of de-inking sludge were investigated. It was observed that the addition of de-inking sludge to cement mortar at a fixed water-to-cement ratio significantly reduced flow properties and increased setting time. Water absorption and volume of permeable voids of cement mortar increased with increased dosage of de-inking sludge, with a corresponding reduction of bulk density. The 91-day compressive strength of mortar samples with 2.5 wt% and 20 wt% de-inking sludge loadings retained 83% and 62% respectively of the reference mortar strength. The corresponding drying shrinkage increased by up to 160% compared to reference samples. However, a de-inking sludge loading of up to 2.5 wt% did not significantly alter measured physical and mechanical properties. The results demonstrate that despite the high moisture absorbance of de-inking sludge due to its organic matter and residual cellulose fibre content, it serves as a potential supplementary additive and its cellulosic content proving to be an active set retardant to cementitious masonry products.

5 páginas, 3 figuras, Supplementary 2 figuras -- PAGS NRS. 2799-2803. Publicado también en, The aim of this work was to develop an innovative method for the internal sizing of paper by use of laccase and hydrophobic compounds. Nine different products containing hydrophobic moieties were tested in combination with laccase derived from Trametes villosa on Eucalyptus globulus kraft pulp in order to assess their internal sizing capability. The strongest internal sizing effect was obtained with lauryl gallate (LG). Heat treatment of the handsheets was found to increase the resistance to water absorption of internally sized samples significantly. Tests were conducted under variable operating conditions, including enzyme and reactant doses and treatment time. In addition to altering the water absorption rate, internal sizing with the laccase-LG treatments was found to affect the mechanical and optical properties of the handsheets. As shown in this work, treatments based on laccase and a hydrophobic compound (particularly lauryl gallate), can provide a new, effective biotechnological method for the internal sizing of paper., BIORENEW (NMP2-CT-2006-026456) of the EU’s Sixth Framework Programme and the FUNCICEL project (CTQ2009-12904) within the framework of Spain’s MICINN.

Poly(lactide)-coated paperboards were prepared by a solution coating method, and the effect of coating to improve properties of paperboard used for the manufacturing of 1-way paper cups was tested. Surface of PLA-coated paperboards was smooth and shiny like PE-coated paperboard, and the coating weight and thickness increased linearly with increasing PLA concentration of coating solution. Tensile strength (TS) and elongation at break (E) of the paperboard also increased after PLA coating. Water vapor barrier or water-resistant properties tested, such as water vapor permeability (WVP), water absorptiveness (WA), and contact angle (CA) of water drop, indicated that water resistance of the paperboard was improved through surface coating with PLA. The increase in water resistance of PLA-coated paperboards was mainly due to the hydrophobicity of PLA and the improvement of water barrier properties increased depending on the PLA concentration. In addition, PLA-coated paperboard showed strong heat sealing property when coated with more than 1 w/v% of PLA. Wet strength of PLA-coated (3, w/v%) paperboard was comparable to or greater than that of PE-coated paperboard. All the test results indicated that the PLA-coated paperboard can be exploited for the manufacturing of 1-way paper cups as an alternative to the PE-coated paperboard.

Summary A common technique to sample airway mucosal ‘surface’ liquids is with absorbing discs of filter paper. The present study examined the efficacy of this technique by analysing tracheal liquids of control and capsaicin (0.1 nmol)-exposed guinea-pig airways. Mucosal fluids, obtained by topically applied discs or by a specific lavage procedure, and tracheal tissue were sampled. The animals had received FITC-dextran (MW 70 kDa) intravenously and this specific plasma tracer was analysed in the sampled material. Under control conditions significantly more FITC-dextran was found in the discs than in the tracheal lavage fluids (P < 0.001) despite the fact that the lavaged mucosal surface was much larger than that covered by the discs, Capsaicin significantly increased the content of FTTC-dextran in all fluids sampled as well as in the airway tissue. In all cases concentrations of FITC-dextran in the disc fluids did not differ much from that in the tissue samples. These data suggest that absorbing discs severely disturb the epithelial-barrier function and sample subepithelial fluid and solutes including macromolecules. As demonstrated in this study by the elevated content of a plasma tracer molecule an inflammatory process may, nevertheless, be traced in the mixture of surface and tissue fluids that is sampled by the discs.

Objective This study analyzed two methods of measuring the absorbing capacity of paper points (PP), testing the hypothesis that there is a positive correlation between the results from the percentage of increase mass (PIM) and the linear dye penetration (LDP) methods. Methods The initial dry weight (IDW) of each PP was recorded using a digital balance before 1-mm introduction into one of the dye solutions, 1% methylene blue (MB) or 1% rodamine B (RB), for 10 s. The PP's were removed from the solution and weighed (final weight – FW). PIM was calculated from the difference between FW and IDW ( n = 50). The LDP was measured using a stereomicroscope and a ruler ( n = 50). Data was statistically analyzed using the Pearson correlation and Student's t tests. Results Moderate positive correlations between LDP and PIM methods were found using methylene blue ( r = 0.6356) and rodamine B ( r = 0.7743), partially confirming the study hypothesis, and suggesting that results from these two methods should be confronted carefully. Significance The results of this study suggest that the most reliable method of measuring the absorbing capacity of paper points is the PIM and investigators should be aware of differences between the two research protocols when comparing results from these two methods (PIM and LDP).

The aim of the project was to tailor the surface of the paper by chemical treatment in order to control and adjust the absorption properties and surface chemistry of the paper. This would enable low and even absorption of printing ink. It was important to increase the know-how of interactions between paper surface and chemical compounds to reach the goal. The results proved that the paper surface chemistry is in key position in the absorption of most printing inks, and the chemistry of paper can be dramatically influenced with very small amount of proper polymer. (5 refs.)

The aim of the project was to tailor the surface of the paper by chemical treatment in order to control and adjust the absorption properties and surface chemistry of the paper. This would enable low and even absorption of printing ink. It was important to increase the know-how of interactions between paper surface and chemical compounds to reach the goal. The results proved that the paper surface chemistry is in key position in the absorption of most printing inks, and the chemistry of paper can be dramatically influenced with very small amount of proper polymer. (5 refs.)

A comparative study of the absorbency properties of different endodontic paper points has been conducted. Twenty standardized absorbent paper points, size 30, from 13 bands (Dentaline, Zipperer, Kerr, Diadent, Roeko novo, Roeko color, Maillefer, P.D., Schein, Spectrapoint, Proclinic, Euronda, and Alpro) of 12 manufacturers were tested. Each dry paper point was weighted using an electronic laboratory balance. A length of 16 mm from the tip was then lowered in distilled water for 5 s, the paper point was weighted again, and the difference between both measurements was taken as the value of the fluid absorbed. Diadent, Kerr, and Dentalite showed significantly higher absorbencies (p0.05) than standardized paper points of the remaining brands. The study demonstrates a wide variation in the absorbency properties of this dental accessory.

Single-walled carbon nanotube (SWNT) papers were successfully prepared by dispersing SWNTs in Triton X-100 solution, then filtered by PVDF membrane (0.22 μm pore size). The electrochemical behavior and the reversible hydrogen storage capacity of single-walled carbon nanotube (SWNT) papers have been investigated in alkaline electrolytic solutions (6 N KOH) by cyclic voltammetry, linear micropolarization, and constant current charge/discharge measurements. The effect of thickness and the addition of carbon black on hydrogen adsorption/desorption were also investigated. It was found that the electrochemical charge–discharge mechanism occurring in SWNT paper electrodes is somewhere between that of carbon nanotubes (physical process) and that of metal hydride electrodes (chemical process), and consists of a charge-transfer reaction (Reduction/Oxidation) and a diffusion step (Diffusion).

This paper presents the results on a study to use paper mill sludge for particleboard production. Single-layer board and three-layer board, with paper sludge on the surface, were fabricated. Four levels of mixing ratios of paper sludge to wood particles (0:100, 15:85, 30:70, and 45:55) were used. The boards were produced with 3% and 4% methylene diphenyl diisocyanate (MDI), and 10% and 12% urea-formaldehyde (UF) adhesives. The bending and shear strengths, water absorption, and thickness swelling of the boards were investigated. The results indicated that the mechanical properties of the boards were negatively affected by the paper sludge amount. Overall, UF-bonded particleboards gave superior mechanical performance, water resistance, and thickness swell than MDI-bonded particleboards. The strengths of the UF-bonded board decreased much more than those of MDI-bonded board as paper sludge content increased. The three-layer boards made from 15% paper sludge with 12% UF satisfied fully the minimum requirements set by EN, ASTM D 1037-99, and ANSI A208.1 standards for general uses.

[reaction: see text] Ketyl radicals with lignin related structures have been generated by means of radiation chemical and photochemical techniques. In the former studies ketyl radicals are produced by reaction of alpha-carbonyl-beta-aryl ether lignin models with the solvated electron produced by pulse radiolysis of an aqueous solution at pH 6.0. The UV-vis spectra of ketyl radicals are characterized by three main absorption bands. The shape and position of these bands slightly change when the spectra are recorded in alkaline solution (pH 11.0) being now assigned to the ketyl radical anions and a pKa = 9.5 is determined for the 1-(3,4,5-trimethoxyphenyl)-2-phenoxyethanol-1-yl radical. Decay rates of ketyl radicals are found to be dose dependent and, at low doses, lie in the range (1.7-2.7) x 10(3) s(-1). In the presence of oxygen a fast decay of the ketyl radicals is observed (k2 = 1.8-2.7 x 10(9) M(-1) s(-1)) that is accompanied by the formation of stable products, i.e., the starting ketones. In the photochemical studies ketyl radicals have been produced by charge-transfer (CT) photoactivation of the electron donor-acceptor salts of methyl viologen (MV2+) with alpha-hydroxy-alpha-phenoxymethyl-aryl acetates. This process leads to the instantaneous formation of the reduced acceptor (methyl viologen radical cation, MV+*), as is clearly shown in a laser flash photolysis experiment by the two absorption bands centered at 390 and 605 nm, and an acyloxyl radical [ArC(CO2*))(OH)CH2(OC6H5)], which undergoes a very fast decarboxylation with formation of the ketyl radicals. Steady-state photoirradiation of the CT ion pairs indicates that 1-aryl-2-phenoxyethanones are formed as primary photoproducts by oxidation of ketyl radicals by MV2+ (under argon) or by molecular oxygen. Small amounts of acetophenones are formed by further photolysis of 1-aryl-2-phenoxyethanones and not by beta-fragmentation of the ketyl radicals. The high reactivity of ketyl radicals with oxygen coupled with the low rates of beta-fragmentation of the same species have an important bearing in the context of the photoyellowing of lignin containing pulps and papers.