BACKGROUND: Wood science and nanomaterials science interact together in two different aspects; a) fabrication of lignocellulosic nanomaterials derived from wood and plant-based sources and b) surface or bulk wood modification by nanoparticles. In this review, we attempt to visualize the impact of nanoparticles on the wood coating and preservation treatments based on a thorough registration of the patent databases. METHOD: The study was carried out as an overview of the scientifically most followed trends on nanoparticles utilization in wood science and wood protection depicted by recent universal filed patents. This review is exclusively targeted on the solid (timber) wood as a subject material. RESULTS: Utilization of mainly metal nanoparticles as photoprotection, antibacterial, antifungal, antiabrasive and functional component on wood modification treatments was found to be widely patented. Additionally, an apparent minimization in the emission of volatile organic compounds (VOCs) has been succeeded. CONCLUSION: Bulk wood preservation and more importantly, wood coating, splay the range of strengthening wood dimensional stability and biological degradation, against moisture absorption and fungi respectively. Nanoparticle materials have addressed various issues of wood science in a more efficient and environmental way than the traditional methods. Nevertheless, abundant tests and regulations are still needed before industrializing or recycling these products.
The measurements of formaldehyde emission (FE) from solid wood, plywood, flooring and blockboard used for building and furnishing materials were obtained using the European small-scale chamber (EN 717-1) and gas analysis (EN 717-2) methods to identify the major sources of formaldehyde among construction and wood products in the Czech Republic. The differences in the FE values reported for various wood products were a function of their structural differences. These results showed that the wood species, plywood type and thickness significantly affected the FE measured by EN 717-2 (P<0.001). The FE values from solid wood ranged between 0.0068 and 0.0036ppm and 0.084-0.014mg/m(2)h. The initial FE ranged from 0.006mg/m(3) for engineered flooring with polyvinyl acetate (PVAc) to 0.048mg/m(3) for painted birch blockboard. Furthermore, the FE dropped noticeably by the end of the measuring period, ranging between 0.006mg/m(3) for engineered flooring with PVAc and 0.037mg/m(3) for painted beech blockboard. Additionally, the initial FE was higher for the painted blockboard (0.035-0.048mg/m(3)) than for the uncoated boards (0.022-0.032mg/m(3)). In the first week after manufacturing, the FE was high, but the decrease in FE was noticeable at the two-week measurement for all of the materials, especially for the painted blockboards.
- MeSH
- dřevo chemie MeSH
- formaldehyd analýza MeSH
- konstrukční materiály MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Geografické názvy
- Česká republika MeSH
This work concerns the role of formaldehyde in the environment and describes the basic indoor and outdoor detection techniques. One of the laboratory techniques, laser photoacoustic spectroscopy, was used for detection of formaldehyde based on its absorption spectrum in a region around 4350 cm-1. A new type of diode laser (GaInAsSb/AlGaAsSb - MQW (Multi-quantum well)) operating at room temperature in combination with a simple resonance photoacoustic cell provides the minimum detectable signal of formaldehyde, ca. 1250 µg m-3, at 4356 cm-1.
A method for determination of formaldehyde in air using 4-amino-3-hydrazino-5-sulfanyl-1,2,4-triazole as chromogenic reagent has been described. The blue coloration formed on an indicator strip was evaluated using reflectance spectrophotometry. The detection limit is at least 0.07 mg m?3 of HCHO (the WHO limit is 0.1 mg m?3) after taking an air sample for 1 min at the flow rate 1 dm3 min-1.
Cíl práce: Posouzení adsorpčních schopností přírodního aluminosilikátu vůči organickým látkám obsaženým v cigaretovém kouři s důrazem na toxické složky (formaldehyd a další aldehydy a ketony nikotin, aromatické sloučeniny a další škodliviny). Metodika: Cigaretový' kouř z hořící cigarety byl prosáván adsorpční trubicí naplněnou vzorkem testovaného aluminosilikátu a následně další adsorpční trubicí naplněnou speciálním adsorbentem ' n Tenax používaným ke kvantitativní adsorpci organických látek v analytice ovzduší. Organické látky zachycené v obou adsorpčních trubicích byly následně analyzovány na tandemu GC-MS. Porovnáním výsledků obou analýz byly stanoveny adsorpční schopnosti aluminosilikátu vůči jednodivým identifikovaným složkám cigaretového kouře. Adsorpce formaldehydu byla posouzena separátním pokusem. Ke kvantitativnímu záchytu formaldehydu byl místo Tenaxu použit silikagel impregnovaný roztokem 2,4-dinitrofenylhydrazinu. Výsledky: Bylo zjištěno, že aluminosilikát přírodního původu přednostně sorbuje z cigaretového kouře především organické látky polární povahy, nepolární látky se bud nesorbují vůbec, anebo jen částečně. Z technického hlediska je zajímavá především dobrá adsorpce formaldehydu, styrénu (karcinogenní látky) a nikotinu (didežitá součást cigaretového kouře). Závěr: Aluminosilikát přírodního původu může účinně sloužit v místnostech s vysokou koncentrací cigaretového kouře či jiných jedovatých látek (např. formaldehyd) ke snižování koncentrací těchto škodlivin.
Objective: The tests of adsorption properties of a natural alumosilicate lo the compounds contained in cigarette smoke with respect to toxic substances (formaldehyde and other aldehydes and ketones, nicotine, aromatic compounds, etc.). Methods: The cigarette smoke was flowed through an adsorption tube filled with the tested alumosilicate followed by an adsorption tube filled with a special adsorbent Tenax used for quantitative adsorption of organic compounds in analyzed atmosphere. The organic substances adsorbed in both adsorption lubes were consequendy analysed by GC-MS. The adsorption capability of the alumosilicate was estimated on the basis of the comparison of the obtained results. The adsorption of formaldehyde was estimated in the second test carried out separately. For the quantitative adst)rption of formaldehyde silicagel impregnated with 2,4-dinitrohydrazine was used. Results: The investigated natural alumosilicate adsorbs preferentially the polar organic compounds from the cigarette smoke, the nonpolar compounds being adsorbed only partially or not at all. From the technical point of wiew the good adsorption of formaldehyde and styrene (carcinogenic substances) as well as that of nicotine (singnificant component of the cigarette smoke) is interesting. Conclusion: The natural alumosilicate can be used in room with high concentration of cigarette smoke or other poisonous substances (e.g. formaldehyde) to reduce their concentrations.
- MeSH
- audiometrie MeSH
- chromozomální aberace MeSH
- dospělí MeSH
- dřevo MeSH
- formaldehyd analýza normy MeSH
- látky znečišťující vzduch v pracovním prostředí analýza normy MeSH
- lidé středního věku MeSH
- lidé MeSH
- otorinolaryngologické nemoci epidemiologie MeSH
- prach analýza normy toxicita MeSH
- Check Tag
- dospělí MeSH
- lidé středního věku MeSH
- lidé MeSH
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- Publikační typ
- srovnávací studie MeSH
