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V magistrski nalogi smo ugotavljali vpliv dekorativnega sloja na emisijo formaldehida iz ivernih plošč. Namen je bil predvsem ugotoviti kakšen je zaviralni učinek oziroma ovira posameznih dekorativnih sistemov, ki se običajno uporabljajo v proizvodnji pohištva. Za analizo emisije formaldehida je bila uporabljena eksikator metoda (ISO 12460-4:2008). Ugotovljeno je bilo, da je večina dekorativnih sistemov imela manjšo emisijo formaldehida od referenčne, kar pomeni, da je večina le teh bila učinkovita pri zaviranju emitiranja formaldehida. Največje emisije formaldehida sta imela impregnirana papirja v primerjavi z referenčnimi ploščami. Še vedno pa so imeli manjšo koncentracijo formaldehida v primerjavi s ploščami, ki so imeli vse površine odprte. HPL 2 in en sloj Belinke imata zelo podobni emisiji formaldehida, in sicer HPL 2 ima 0,0387 mg/L, medtem ko en sloj Belinka ima 0,0383 mg/L. Najmanjšo emisijo formaldehida, kar pomeni najbolj učinkovit zaviralec emitiranja, predstavlja interier Belinka z dvema nanosoma. Lahko rečemo, da so načeloma vsi dekorativni materiali imeli nek zaviralni učinek emitiranja formaldehida. In the master's thesis, we determined the influence of a decorative layer on the emission of formaldehyde from particleboards. The main purpose was to find out what is the inhibitory effect or obstacle of individual decorative systems that are usually used in the production of furniture. The desiccator method (ISO 12460-4:2008) was used to analyze the formaldehyde emission. It was found that most of the decorative systems had a lower formaldehyde emission than the reference boards, which means that most of them were effective in suppressing the emission of formaldehyde. Impregnated papers had the highest formaldehyde emissions compared to the reference panels. However, they still had a lower concentration of formaldehyde compared to panels that had all surfaces open. HPL 2 and one layer of Belinka have very similar formaldehyde emissions, namely HPL 2 has 0,0387 mg/L, while one layer of Belinka has 0,0383 mg/L. The lowest formaldehyde emissions, which means the most effective emission inhibitor, was found for the interior of Belinka with two layers. It can be said that, in principle, all decorative materials had some inhibitory effect on the emissions of formaldehyde.

In order to further improve the performance of impregnated paper decorated blockboard (ecological board), high-density fiberboard (HDF) was selected as the equilibrium layer to replace the commonly used poplar veneer. Results showed that the performance of HDF ecological board can be comparable to that of poplar veneer ecological board. It had good appearance quality, and its surface scratch resistance, surface wear resistance, water resistance and mechanical properties met the requirements of National Standard GB/T 34722-2017. The surface cracking resistance of the ecological board prepared with HDF as the equilibrium layer reached the highest level (grade 5), far better than that of the poplar veneer ecological board. This was because HDF was a relatively homogeneous material, and its dry shrinkage in both the transverse direction and along the grain direction was much lower than that of the poplar veneer. This characteristic of HDF made it possible to improve the dimensional stability and bending resistance of blockboard substrates under dry and hot conditions. The formaldehyde emission of the HDF ecological board was higher than that of the poplar veneer ecological board, but it met the formaldehyde emission requirements of indoor materials according to GB 18580-2001.

The purpose of the present study is to offer an optimal model to predict the tensile index of the paper being consumed to make veneer impregnated with different weight ratios of modified starch (from 3.18 to 36.8%) to urea formaldehyde resin (WR) containing different formaldehyde to urea molar ratios (MR, from 1.16:1 to 2.84:1) enriched by different contents of silicon nano-oxide (NC, from 0 to 4%) using multiple linear regression (MLR) and adaptive neuro-fuzzy inference system (ANFIS) and compare the precision of these two models to estimate the response being examined (tensile index). Fourier-transform infrared spectroscopy (FTIR) and transmittance electron microscopy (TEM) were also used to analyze the results. The results of studying the adhesive structure using FTIR analysis showed that as the WR increased to the maximum level and MR increased to the average level (3%), more ether and methylene linkage forms due to cross-linking. TEM analysis also indicated that if an average level of silicon nano-oxide is applied, there will be more cross-linking due to the more uniform distribution and suitable interactions between the adhesive and nanoparticles. The modeling results showed that the ANFIS model estimates have been closer to the actual values compared to the MLR model. It can be concluded that the model offered by ANFIS has a higher potential to predict the tensile index of the paper impregnated with the combined adhesive of UF resin and modified starch. However, the MLR model could not offer a good estimate to predict the response. According to the preferred approach to predict the most effective property of resin coated paper, modelling would be useful to the research community and the results are beneficial in industrial applications without spending more cost and time.

International audience; This paper is an experimental study of the electrical conduction of mineral-oil/solid interfaces in negative polarity. This study is performed in a point-plane configuration immersed in mineral oil submitted to impulse voltages. The interface is assembled with an inclined solid in contact with the point electrode tip. Charge recordings and conduction currents of different combinations of mineral-oil/solid interfaces are reported. Different polymers and oil-impregnated papers are used as the solid materials. It is found that for voltages lower than the inception voltage, the injection of charge belongs to a weak injection regime. The spatial limitation with solids of similar permittivity as the mineral oil decreases the charge injection. The charge injection at mineral-oil/solid interfaces follow two conduction current type characteristics. Experiments with mineral-oil/PTFE interface shows the existence of a transition between both conduction current types if the applied voltage is increased.

This paper investigates synthesis of impregnating phenol–formaldehyde resins in which up to 30 wt % formulation phenol is replaced by cardanol, a plant product. The resulting resins were used to make impregnated paper for laminating the plywood and particle boards. The synthesis and structure of cardanol-containing water-soluble resols were studied by IR spectroscopy and 1H NMR, and the reactivity of phenol cardanol formaldehyde resins at 80–150°C was studied by differential scanning calorimetry. The optimal amount of cardanol in relation to phenol in the resin structure was determined. It is shown that the introduction of cardanol into the composition of phenol–formaldehyde resins reduces the impregnation time of kraft paper and improves the surface quality and elasticity of the impregnated paper, with the use of such paper making it possible to decrease the water absorption of laminated particle board materials and the emission of formaldehyde. © 2021, Pleiades Publishing, Ltd.

This paper systematically studies the effect of Fe3O4 nanoparticle size on the insulation performance of nanofluid impregnated paper. Three kinds of Fe3O4 nanoparticles with different sizes and their nanofluid impregnated papers were prepared. Environmental scanning electron microscopy (ESEM) and infrared spectroscopy were used to analyze the combination of Fe3O4 nanoparticles and nanofluid impregnated paper. The effect of nanoparticle size on breakdown voltage and several dielectric characteristics, e.g., permittivity, dielectric loss, of the nanofluid impregnated paper were comparatively investigated. Studies show that the Fe3O4 nanoparticles were bound to impregnated paper fibers by O&ndash, H bonds, while the relative permittivity and dielectric loss of the nanofluid impregnated papers were increased. Meanwhile, the increase of trap depth, caused by the nanoparticles, can trap the electric charge and improve the breakdown strength. The test results show that the direct current (DC) and alternating current (AC) breakdown voltages of nanofluid impregnated paper increased by 9.1% and 10.0% compared to FR3 nanofluid impregnated paper, respectively.

This paper systematically studies the effect of Fe3O4 nanoparticle size on the insulation performance of nanofluid impregnated paper. Three kinds of Fe3O4 nanoparticles with different sizes and their nanofluid impregnated papers were prepared. Environmental scanning electron microscopy (ESEM) and infrared spectroscopy were used to analyze the combination of Fe3O4 nanoparticles and nanofluid impregnated paper. The effect of nanoparticle size on breakdown voltage and several dielectric characteristics, e.g., permittivity, dielectric loss, of the nanofluid impregnated paper were comparatively investigated. Studies show that the Fe3O4 nanoparticles were bound to impregnated paper fibers by O–H bonds, while the relative permittivity and dielectric loss of the nanofluid impregnated papers were increased. Meanwhile, the increase of trap depth, caused by the nanoparticles, can trap the electric charge and improve the breakdown strength. The test results show that the direct current (DC) and alternating current (AC) breakdown voltages of nanofluid impregnated paper increased by 9.1% and 10.0% compared to FR3 nanofluid impregnated paper, respectively.

This study was carried out in order to investigate the effects of different types of resins and also their mixtures on the impregnated paper properties. In this regard, pure urea resin (100%), mixture of melamine and urea resins with various combinations (60/40 and 70/30 and 50/50), mixture of nano-fiber cellulose ratios of 1, 2 and 3 percent with urea resin and pure PVA (100%) were used to impregnate of newsprint basic paper of Mazandaran wood and paper industries. Immersion of samples in the impregnation step were done in two time of 5 and 10 seconds. Next, melamine resin was used for surface coating and then absorption of resin in the impregnation and coating process measured. Results showed that in the impregnation step with pure urea (100%), in the respect of absorption rate and surface properties of melamine paper, the best time of impregnation was obtained 10 seconds. In the combined treatment, adding up to 30% melamine to urea resin, as impregnation step resin, offers better properties in terms of stain resistance, cigarette resistance, resistance to cracking and resistance to hot water steam for impregnatedmade paper. By adding nanocellulose up to 1% in impregnation resin, better properties is obtained for melamine paper. Also, PVA as impregnation resin, can be offer similar quality to pure urea in the resulting melamine papers.

International audience; Ethylene glycol and caprolactam were added during the synthesis process of melamine formaldehyde (MF) resins to develop a new MF formulation with high flexibility, storage stability, and low formaldehyde emissions that can be used for the impregnation of papers. It was demonstrated that the MF resins with amounts of ethylene glycol (molar ratio of ethylene glycol to melamine was 1.0) and caprolactam (molar ratio of caprolactam to formaldehyde was 0.12) achieved higher storage stability, flexibility, and lower free formaldehyde content. The impregnated papers made from these MF resins displayed good dry and wet tensile strength and passed the relevant standard specifications for decorative paper on wood-based panels. The size exclusion chromatography (SEC) and Fourier transform-infrared spectrometry (FT-IR) studies showed that the MF resins produced via incorporation of ethylene glycol and caprolactam had a different molecular weight distribution and polymeric structure.

Submitted by hugo lira (hugovictorsb@gmail.com) on 2018-09-03T13:11:08Z No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) 1. Tese de Doutorado - Grafe Pontes.pdf: 3805661 bytes, checksum: dfa0075a7b7b500d45f3604fdd0ab8b0 (MD5) Approved for entry into archive by Divis??o de Documenta????o/BC Biblioteca Central (ddbc@ufam.edu.br) on 2018-09-10T15:39:31Z (GMT) No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) 1. Tese de Doutorado - Grafe Pontes.pdf: 3805661 bytes, checksum: dfa0075a7b7b500d45f3604fdd0ab8b0 (MD5) Approved for entry into archive by Divis??o de Documenta????o/BC Biblioteca Central (ddbc@ufam.edu.br) on 2018-09-10T15:49:55Z (GMT) No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) 1. Tese de Doutorado - Grafe Pontes.pdf: 3805661 bytes, checksum: dfa0075a7b7b500d45f3604fdd0ab8b0 (MD5) Made available in DSpace on 2018-09-10T15:49:55Z (GMT). No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) 1. Tese de Doutorado - Grafe Pontes.pdf: 3805661 bytes, checksum: dfa0075a7b7b500d45f3604fdd0ab8b0 (MD5) Previous issue date: 2018-05-02 FAPEAM - Funda????o de Amparo ?? Pesquisa do Estado do Amazonas The use of chemical insecticides becomes important in Aedes aegypti control programs. Over the years, epidemiological studies have demonstrated the inefficiency of synthetic insecticides due to the resistance acquired with the use in activities related to vector control in tropical diseases, especially dengue. For a better effectiveness of vector control programs, the search for new alternatives is necessary. The interest in entomopathogenic fungi for biological control is in great growth. However, the work on controlling the different stages of life of A. aegypti and the transmission of mycoses between individuals and their offspring are still discrete. In order to contribute with new compounds and integrated control of dengue, the present project aims to evaluate the entomopathogenic activity of fungi isolated from Amazonian soil in larvae and adults of A. aegypti, and their residual effects on the life cycle considering the number of eggs and larvae and adults. The proposed methodology for this work is the use of conidia of fungal isolates previously selected by genera that have relevance in biological control or that demonstrate positive results when used in probe / sorting insects, Tenebrio molitor. For the application of the formulations conidia were used in aqueous suspensions for treatment in larvae, and for adults was used aqueous suspensions impregnated in filter paper placed in Kit of the World Health Organization used to evaluate the susceptibility of chemical insecticide. The present work proposes a practical methodology for sexing and separating adults through the selection of pupae, in order to evaluate the degree of infestation and the entomopathogenic effect on larvae and adults of A. aegypti. avoiding the premature death of the insect by the use of Castro's catcher at the time of adult withdrawal from the colony. The results obtained evidenced the potential of four fungal isolates IPC 2.1 and IPS 3.1 isolated from Amazonian soil, and two other isolates from other insects and from soil samples IBCB 66 and IBCB 425, widely used to control insects in agriculture, and evaluated for the control of larvae and adults of the mosquito vector dengue. The results between the two methodologies showed the best applicability for the fungal isolates and their use in the control of A. aegypti, responsible for a great social impact on the public health of the Amazon due to the transmission of several arboviruses. O uso de inseticidas qu??micos tornou importante nos programas de controle do Aedes aegypti. Com o passar dos anos, os estudos epidemiol??gicos demonstraram a inefici??ncia dos inseticidas sint??ticos devido ?? resist??ncia adquirida com a utiliza????o nas atividades relacionadas ao controle de vetores em doen??as tropicais, especialmente dengue. Para uma melhor efic??cia dos programas de controle de vetores, h?? necessidade da busca de novas alternativas. O interesse em fungos entomopatog??nicos para controle biol??gico encontra-se em amplo crescimento. Entretanto, ainda s??o discretos os trabalhos no controle dos diferentes est??gios de vida do A. aegypti, e a transmiss??o de micoses entre seus indiv??duos e sua prole. Com o intuito de contribuir com novos compostos e no controle integrado da dengue, Febre Chikungunya e Zika v??rus. O presente projeto tem como objetivo avaliar a atividade entomopatog??nica de fungos isolados de solo da Amaz??nia em larvas, adultos de A. aegypti, e seus efeitos residual sobre o ciclo de vida considerando o n??mero de ovos e larvas e adultos. A metodologia proposta para esse trabalho visa ?? utiliza????o de con??dios dos isolados f??ngicos previamente selecionados por g??neros que tenham relev??ncia no controle biol??gico ou que demonstrem resultados positivos quando utilizados em insetos sonda/triagem, Tenebrio molitor. Para a aplica????o das formula????es foram utilizados con??dios em suspens??es aquosas para tratamento em larvas, e para adultos foi utilizado suspens??es aquosas impregnados em papel filtro colocados em Kit da Organiza????o Mundial de Sa??de utilizado para avalia????o de susceptibilidade de inseticida qu??mico. Os bioensaios foram realizados em condi????es de laborat??rio, avaliando-se o grau de infesta????o e o efeito entomopatog??nico sobre as larvas e adultos de A. aegypti, O presente trabalho prop??e uma metodologia pr??tica para sexagem e separa????o de adultos por meio de sele????o de pupas, evitando a morte prematura do inseto pelo uso de capturador de Castro no momento de retirada de adultos da col??nia. Os resultados obtidos evidenciaram o potencial de quatro isolados f??ngicos, IPC 2.1 e IPS 3.1 isolados de solo da Amaz??nia, e outros dois isolados de outros insetos e de amostras de solo, IBCB 66 e IBCB 425, amplamente utilizados para controle de insetos na agricultura, e avaliados para combate de larvas e adultos do mosquito vetor da dengue, Febre Chikungunya e Zika v??rus. Os resultados entre as duas metodologias demonstraram a melhor aplicabilidade para os isolados f??ngicos e sua utiliza????o no controle do A. aegypti, respons??veis por grande impacto social na sa??de p??blica da Amaz??nia devido a transmiss??o de diversas arboviroses.

Liquid nitrogen impregnated PPLP and Kraft lapped papers are compared in terms of space charge distribution measurements for high voltage insulation in high power HVDC superconducting cables. Measurements with the pressure-wave-propagation method have shown that PPLP and Kraft paper samples behave similarly up to 30 kV/mm. No space charge has been observed in the insulation. Partial discharges at the interfaces of the carbon loaded paper electrodes are observed and produce an injection like phenomenon.

A simple field method for determination of fluoride in drinking water using handmade fluoride reagent paper impregnated by aluminium quinalizarin complex was developed. Fluoride reacts with the impregnated reagent paper to release the free ligand with new colour, orange different from that of the complex. The change in the colour, which is proportional to the amount of fluoride, was measured by the Arsenator. The functionality of the Arsenator which is based on a photometric measurement of spot on the reagent paper is expanded to analyse fluoride. The method allows a reliable determination of fluoride in the range 0.0–2.0 mg L−1. Further spectrophotometric determinations of fluoride showed that Beer’s law is obeyed in the range of 0.3–5.0 mg L−1 at 553 nm. Sensitivity, detection limit, quantitation limit, and the percentage recovery of 1.5 mg L−1 fluoride were found to be 0.117 μg mL−1, 0.1 mg L−1, 0.3 mg L−1, and 101.2 respectively.

Balıkesir Üniversitesi, Fen Bilimleri Enstitüsü, Makina Mühendisliği Ana Bilim Dalı, Bu çalışmada, orman endüstrisi artıklarından Üre Formaldehit (UF) ve Melamin Formaldehit (MF) içeren emprenyeli dekor kağıtlarının pirolizinin değerlendirilmesi amaçlanmıştır. Emprenyeli kağıt atıklarının doğaya atılması kirliliğe sebep olduğundan ve tekrar kullanılmaları da kalite sorunlarına yol açabildiğinden, piroliz bu atıkların kullanımı için bir alternatif olarak ele alınmıştır. Bu çalışma kapsamında pirolitik yağın enerji potansiyeli saptanmış FTIR analizine yer verilmiştir. Farklı reaksiyon ve ısıl uygulama şartlarında piroliz prosesinin verimlilik fizibilitesi gerçekleştirilmiştir. Sıcaklık ve alıkonma zamanının ürün (katı – sıvı – gaz) oranlarını etkilediği saptanmıştır. En yüksek sıvı ürün verimi kalorifik değerin çalışılan en yüksek sıcaklıkta elde edildiği görülmüştür. Bu çalışma emprenyeli kâğıtların pirolizinin kapsamlı tahlili için bir ön çalışma olarak tanımlanabilir ve mevcut sonuçlar gelecek çalışmalar için umut vericidir., This study aims evaluation of pyrolysis of the impregnated decorative papers which are forestry industry waste containing urea-formaldehyde (UF) and melamine-formaldehyde (MF) resin. Since casting away the impregnated paper wastes cause pollution, and re-use of them can lead to quality issues, pyrolysis is taken as an alternative to utilize these wastes. Within the scope of this study, energy potentials of the pyrolytic oil is determined and FTIR analysis of the Pyrolysis oil is made. The productivity feasibility of pyrolysis processes with various thermal treatments and reaction conditions is carried out. Calorific value of the pyrolysis oil is analysed. It’s determined that temperature and residence time effects product (Char – Oil – Gas ) percentages. It’s seen that maximum liquid product yield and maximum calorific value is obtained at the higher temperature studied. This study may be described as a prestudy of overall analysis of impregnated paper pyrolysis and the existing results are encouraging for further experiments.

Two organic–inorganic hybrid sol–gel coatings were developed in order to modify the surface energy and moisture behaviour of the commercial impregnated paper. The surface characteristics of the paper samples were studied by scanning electron microscopy (SEM), confocal laser scanning microscopy (CLSM), atomic force microscopy (AFM), attenuated total reflectance Fourier transform infrared spectrometry (ATR-FTIR), X-ray photoelectron spectroscopy (XPS) and time of flight secondary ion mass spectroscopy (ToF-SIMS). It was found that the applied sol–gel coatings as well as the curing process changed the surface structural and chemical properties of the impregnated paper. The chemical bonding between the hydroxyl groups present on paper surface and silanol groups from sol–gel coatings was confirmed by the FTIR spectra. The measured surface energies divided into polar and dispersive components indicated that the coating B resulted in less polar surface than did the coating A which was more polar than the reference (the impregnated paper with water and heat treatment). Coating B brought about the lowest total surface energy. It was obtained that the water repellence of the impregnated paper was improved by both coatings and the curing process.

Two silane-based hybrid coatings were developed to modify the surface energy of phenolic resin impregnated paper. The coated paper samples were further pressed onto surfaces of plywood. The surface properties and water repellence of coated paper were investigated by AFM, XPS and water contact angle measurements. The water absorption of plywood with pressed paper was studied by water uptake tests. It was found that the sol-gel coatings had slightly improved the water repellence of the impregnated paper. The water absorption of plywood was also slightly decreased.

This paper introduces an experimental study on the propagation of negative streamers along mineral oil-solid interfaces. A standard type of impregnated paper and different polymeric films (made of PET, PTFE and PVDF) are selected as solid materials immersed in mineral oil. The effect of the solid material on the streamer propagation along the interface formed with transformer oil is studied. Streamer velocities classified as first mode propagation point cathode are reported. Voltage gradient of the streamer channel and its stopping voltage are calculated for all the cases. Comparison of streamer charge and stopping length propagation are reported. QC 20160212. QC 20160318

Objective To determine the efficacy of WHO impregnated paper and CDC coated bottle based on number of storage days and number of times of consecutive use, in the assessment of insecticide vector susceptibility tests in laboratory and field conditions. Methods Larvae and pupae of Anopheles gambiae s.l. mosquitoes were collected from the breeding sites in Seme-Kpodji and Cotonou districts in Southern Benin in April 2013 during the first rainy season. Anopheles gambiae s.l. mosquitoes were also collected from the breeding sites in Parakou district in Northern Benin in May 2013 at the beginning of the rainy season. Susceptibility tests were done using impregnated paper with bendiocarb (0.1%) following WHO protocol and stock solutions of permethrin (21.5 μg per bottle) and deltamethrin (12.5 μg per bottle) following CDC protocol on unfed female mosquitoes aged 2-5 days old. These bioassays were repeated a certain number of times. The temperature and relative humidity were monitored and recorded during the susceptibility tests. Results This study showed that a WHO impregnated paper with bendiocarb could be used four times during four consecutive days in field conditions. Regarding a Wheaton coated bottle with permethrin or deltamethrin, they could be used at least three times during four consecutive days in laboratory conditions. Conclusions The day storage and the number of times that a WHO impregnated paper and a CDC coated bottle maintained their efficacy are useful in the assessment of insecticide vectors susceptibility tests.