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The most widely used in construction materials industry are ceramic and lime bricks. Higher energy consumption and several ecological problems make their manufacture to become more and more expensive. The growing market of construction works and constant extension of real estate property increases the demand for cheap and new materials with desired features. As a result of many years intensive scientific researches there is now a practical possibility to offer an alternative and unique sand and water based products technology of manufacture (bricks, wall, floor and roofing tiles, sanitary materials, heat insulating and acid proof materials, decorations etc.) – all of them of desired size, shape and colour. The experience of the structural materials technology development shows that building industry will obtain improved service life and performance from quartz sand suspensions as field installations will continue to move toward adopting and utilizing practices based on technology described herein, rather than on cement technology. This type of manufacture is very profitable for the countries having the deposits of sand everywhere situated and being extracted at very low prices. Relative to conventional construction materials sand and water made products (SWP) with mechano-chemical binders will continue to gain in popularity because of the following advantages: low energy consumption and low prices for the products; ecological safety of the manufacture process and of the ready-made products; good mechanical and design properties; moisture and cold proofness; surface need not be fired; no shrinkage of the products after drying; simple to manufacture a variety of different products; ready availability and flexibility in design; absence of manufacture wastes., У промисловості будівельних матеріалів найбільш широко використовуються керамічна і силікатна цегла. Високе енергоспоживання та деякі екологічні проблеми роблять їх виробництво все дорожчим. Зростаючий ринок будівельних робіт і постійне розширення об’єктів нерухомості збільшує попит на дешеві та нові матеріали з бажаними характеристиками. В результаті багаторічних інтенсивних наукових досліджень з’явилася практична можливість запропонувати альтернативну і унікальну технологію виробництва продуктів на основі піску і води (цегла, стінова, підлогова і покрівельна плитка, сантехнічні матеріали, теплоізоляційні та кислототривкі матеріали, декоративні вироби тощо) – усі вони бажаного розміру, форми та кольору. Досвід розвитку технології конструкційних матеріалів свідчить про те, що у порівнянні з традиційними, у матеріалів з ультрадисперсною структурою у декілька разів збільшується мікротвердість, а питома поверхня на порядок, що сприяє зниженню температури спікання порошків. Запропонована технологія виробництва матеріалів будівельного призначення відкриває один з перспективних напрямків у розвитку нанотехнологій – створення надтвердих і надміцних матеріалів для будівельної індустрії. Цей вид виробництва дуже вигідний для країн, де повсюдно розташовані поклади піску, який видобувається за дуже низькими цінами. Порівняно зі звичайними будівельними матеріалами вироби з піску та води (гідросуспензій кремнезему) на механохімічному в’яжучому продовжуватимуть набирати популярність завдяки таким перевагам: низьке енергоспоживання та низька ціна на вироби; екологічна безпека процесу виробництва і готової продукції; хороші механічні та конструктивні властивості; вологостійкість і морозостійкість; відсутність необхідності випалу виробів; відсутність усадки виробів після сушіння; простота у виготовленні різноманітних виробів; доступність і гнучкість дизайну; відсутність відходів виробництва.

Solar-reflective thermal insulating coating (SRC) has received great attention because of its desired heat reflective properties and water repellency, which may impart high-value to cellulosic paper via industrially well-established surface coating process. However, the feasibility and possibility of surface application of SRC to cellulosic paper have not been explored. Herein, in the present work, SRC was designed/developed and subsequently used in the surface application to cellulosic paper. Effect of feeding level of titanium dioxide nanoparticles (nano-TiO2) on rheological behavior of the coating, as well as heat-reflective properties, water repellency and mechanical properties of the surface-coated paper was studied. Results showed that the as-obtained coating samples exhibited a notable shear-thinning behavior and displayed strong dependence of rheological behavior on nano-TiO2 amount. Furthermore, the increased nano-TiO2 amount appeared to induce the improved hemispherical emittance of coated paper. The coating weight was also found to exert a positive effect on the hemispherical emittance of coated paper. In addition, it was confirmed that the nano-TiO2 addition played an important role in improving the water repellency and mechanical properties of coated paper.

Rapid diagnosis by using small, simple, and portable devices could represent one of the best strategies to limit the damage and contain the spread of viral, bacterial or protozoa diseases, principally when they can be transmitted by air and are highly contagious, as some respiratory viruses are. The presence of antibodies in blood or serum samples is not the best option for deciding when a person must be quarantined to stop transmission of disease, given that cured patients have antibodies, so the best diagnosis methods rely on the use of nucleic acid amplification procedures. Here we present a very simple device and detection principle, based on paper discs coupled to contactless conductivity (C4D) sensors, can provide fast and easy diagnostics that are needed when an epidemic outbreak develops. The paper device presented here solves one of the main drawbacks that nucleic acid amplification tests have when they are performed outside of central laboratories. As the device is sealed before amplification and integrally disposed in this way, amplimers release cannot occur, allowing repetitive testing in the physician’s practice, ambulances, or other places that are not prepared to avoid cross-contamination of new samples. The use of very low volume samples allows efficient reagent use and the development of low cost, simple, and disposable point-of-care diagnostic systems., Author summary In 2005, the World Health Organization (WHO) recognized Chagas Disease as a neglected tropical disease. Meanwhile the serological tests, recommended by WHO, can be performed for chronic disease diagnosis, the nucleic acid amplification tests must be performed for the detection of the acute phase of the disease. Although the existing laboratory diagnosis tests for Chagas Disease are sensitive and highly reproducible, they cannot be performed in rural, low infrastructure environments, where this disease prevails. In this sense, the use of simple and portable analytical devices may be able to offer an affordable solution to this problem, allowing fast sampling, diagnosis and treatment prescription in one simple and fast intervention, as the performed by short term medical missions. In this study we show for the first time a diagnosis test comprising low cost materials and employing a contactless and label-free conductivity detection system that is used to read the result of a nucleic acid amplification reaction. The test showed high sensitivity for Chagas Disease diagnosis showing the potential to be used in rural and low income places.

In this review, we summarize the recent progress in thermal conductivity analysis of nanocellulose materials called cellulose nanopapers, and compare them with polymeric materials, including neat polymers, composites, and traditional paper. It is important to individually measure the in-plane and through-plane heat-conducting properties of two-dimensional planar materials, so steady-state and non-equilibrium methods, in particular the laser spot periodic heating radiation thermometry method, are reviewed. The structural dependency of cellulose nanopaper on thermal conduction is described in terms of the crystallite size effect, fibre orientation, and interfacial thermal resistance between fibres and small pores. The novel applications of cellulose as thermally conductive transparent materials and thermal-guiding materials are also discussed.

Günümüzde mobilya ve ağaçişleri sektörlerinde kullanılan malzemelerin birçoğu ahşap esaslı kompozitlerden üretilmektedir. Bunun en önemli nedeni ahşap esaslı kompozitlerin hafifliği ve kullanım yerinin gerektirdiği yüksek performans özelliklerine sahip olmasıdır. Bu çalışmada iç katmanı atık kâğıt olan 8 farklı panel kaplama kullanılmıştır. Panellerin kompozit hale getirilmesinde üre formaldehit tutkalı tercih edilmiştir. Hazırlanan panellerin rutubet, yoğunluk, eğilme direnci, elastikiyet modülü, ısı iletkenlik, ısı geçirgenlik ve ses geçiş kaybı değerleri araştırılmıştır. Deneyler sırasında yoğunluk için TS EN 323, rutubet için TS EN 322, eğilme direnci için TS EN 310, ısı iletkenlik ve ısı geçirgenlik katsayıları TS EN 12667 ve ses geçiş kaybı için TS EN ISO 10534-2 standartları esas alınmıştır. Sonuç olarak yoğunluk değerleri 0,45-0,6 gr/cm3 arasında, rutubet değerleri % 6 ile % 7 arasında, eğilme direnci ortalama 6 N/mm2 ile 11 N/mm2 arasında ve eğilmede elastikiyet modülü değeri ortalama 1500 N/mm2 ile 4000 N/mm2 arasında bulunmuştur. Isı iletkenlik katsayısı 0,105 W/m.K ile 0,075 W/m.K arasında, ısı geçirgenlik katsayısı 5,851 W/m2.K ile 3,913 W/m2.K arasında bulunmuştur. Ses geçiş kaybı değerleri malzeme dış katman yapısına göre incelendiğinde en yüksek ses geçiş kaybı 49,29 dB, 3 mm kontrplak kaplamalı atık kâğıt esaslı panellerden elde edilmişken en düşük ses geçiş kaybı 31,06 dB, 4 mm MDF kaplamalı atık kâğıt esaslı panellerden elde edilmiştir. Ses geçiş kaybı değerleri frekans bazında incelendiğinde ise en düşük ses geçiş kaybı 18,98 dB değeri 160 Hz frekansta elde edilmişken, en yüksek ses geçiş kaybı 70,08 dB değeri ise 6300 Hz frekansta elde edilmiştir. Nowadays, most of the materials used in furniture and woodworking industries are produced from wood-based composites. The most important reason for this is the light weight of wood-based composites and the high-performance properties required by the place of use. In this study, 8 different panel coatings with inner layer of waste paper were used. Urea formaldehyde glue was preferred for making the panels composite. Moisture, density, flexural strength, modulus of elasticity, thermal conductivity, heat permeability and sound transmission loss of the prepared panels were investigated. During the experiments, TS EN 323 for density, TS EN 322 for moisture, TS EN 310 for bending resistance, TS EN 12667 for thermal conductivity and heat transmission coefficients and TS EN ISO 10534-2 for noise transmission loss were used. Consequently, density values are between 0,45-0,6 gr / cm3, moisture values are between 6% and 7%, bending resistance is between 6 N / mm2 and 11 N / mm2 and bending elastic modulus value is 1500 N / mm2 to 4000 N / mm2. The thermal conductivity coefficient was found to be between 0,105 W / m.K and 0,075 W / m.K, and the thermal conductivity coefficient was found to be 5,851 W / m2.K and 3,913 W / m2.K. When the sound transmission loss values were examined according to the material outer layer structure, the highest sound transmission loss was obtained from 49,29 dB, 3 mm plywood coated waste paper based panels, while the lowest sound transmission loss was obtained from 31,06 dB, 4 mm MDF coated waste paper based panels. When the sound transmission loss values were examined on the frequency basis, the lowest sound transmission loss was obtained at a frequency of 18.98 dB at a frequency of 160 Hz, and the highest sound transmission loss at a frequency of 70.08 dB at a frequency of 6300 Hz. 90

Nanofluids, formed by adding nanoscale particles to insulating oil, are stable and homogeneous suspensions that present advanced performance of electrical insulation and heat dissipation. This study shows a comprehensive literature review based on the related results of nano-modified insulating oils (both mineral and vegetable insulating oils) to analyse the preparation methods, stability, dielectric spectroscopy, thermal conductivity, breakdown characteristics under AC and DC voltage, the thermal aging performance of nanofluids and oil-paper interaction. Then theoretical models have been introduced to explain the electrical mechanism of nanofluids. In addition, future research is proposed for nanofluids which would be low cost, highly stable and practically applicable to the power transformers.

Structural characteristics of benzene-ethanol-extracted lignin (BEL) and acetone-extracted lignin (AL) precipitated from black liquor were identified by elemental analysis, FTIR, (13)C NMR, and (1)H NMR, while the thermal behaviors were examined with thermogravimetric-Fourier transform infrared spectroscopy (TG-FTIR). The frequency of β-O-4 bonds per 100 C9 monomeric units was 28 and 17 for BEL and AL. Two-stage pyrolysis processes were observed for the two lignins. The mass loss rate of the initial solvent evolution stage (110-180 °C) of BEL was greater than that of AL. The two lignins presented slightly different mass loss curves and evolution profiles of gases in the main pyrolysis stage (280-500 °C). A global kinetic model was proposed for lignin pyrolysis and activation energies of 39.5 and 38.8 kJ/mol was obtained for BEL and AL. The results enhance understanding of lignin pyrolysis and facilitate commercial utilization of black-liquor lignin.

The high thermal conductivity of graphene and few-layer graphene undergoes severe degradations through contact with the substrate. Here we show experimentally that the thermal management of a micro heater is substantially improved by introducing alternative heat-escaping channels into a graphene-based film bonded to functionalized graphene oxide through amino-silane molecules. Using a resistance temperature probe for in situ monitoring we demonstrate that the hotspot temperature was lowered by ∼28 °C for a chip operating at 1,300 W cm−2. Thermal resistance probed by pulsed photothermal reflectance measurements demonstrated an improved thermal coupling due to functionalization on the graphene–graphene oxide interface. Three functionalization molecules manifest distinct interfacial thermal transport behaviour, corroborating our atomistic calculations in unveiling the role of molecular chain length and functional groups. Molecular dynamics simulations reveal that the functionalization constrains the cross-plane phonon scattering, which in turn enhances in-plane heat conduction of the bonded graphene film by recovering the long flexural phonon lifetime., The high thermal conductivity of graphene is considerably reduced when the two-dimensional material is in contact with a substrate. Here, the authors show that thermal management of a micro heater is improved using graphene-based films covalently bonded by amino-silane molecules to graphene oxide.

New composite boards with low-thermal conductivity produced from a mixture of solid wastes from tissue paper manufacturing (solid waste TPM) and corn peel have been developed. The effects of solid waste TPM/corn peel ratio on the properties of the boards were investigated and the possibility of using recycled polystyrene packaging foam as a laminating agent to improve the quality of the boards was also evaluated. Our results show that the density of the particleboards decrease with increasing the amount of corn peel added in the mixture, leading to a decrease in thermal conductivity of the final product. In contrary, larger amount of solid waste TPM added in the mixture produced stronger boards. The lamination of recycled polystyrene on the surface of particleboards improves the mechanical properties and reduces the thickness swelling of the boards. The best improvement in mechanical properties and swelling resistance could be achieved when 15% polystyrene (w/v) was coated on the surface of the boards.

While drying of paper and paper coatings is expensive, with significant energy requirements, the rate controlling mechanisms are not currently fully understood. Two two-dimensional models are used as a first approximation to predict the heat transfer during hot air drying and to evaluate the role of various parameters on the drying rates of porous coatings. The models help determine the structural limiting factors during the drying process, while applying for the first time the recently known values of coating thermal diffusivity. The results indicate that the thermal conductivity of the coating structure is not the controlling factor, but the drying rate is rather determined by the thermal transfer process at the structure surface. This underlines the need for ensuring an efficient thermal transfer from hot air to coating surface during drying, before considering further measures to increase the thermal conductivity of porous coatings.

The toxicity of the most efficient fire retardant additives is a major problem for polymeric materials. Cellulose nanofiber (CNF)/clay nanocomposites, with unique brick-and-mortar structure and prepared by simple filtration, are characterized from the morphological point of view by scanning electron microscopy and X-ray diffraction. These nanocomposites have superior fire protection properties to other clay nanocomposites and fiber composites. The corresponding mechanisms are evaluated in terms of flammability (reaction to a flame) and cone calorimetry (exposure to heat flux). These two tests provide a wide spectrum characterization of fire protection properties in CNF/montmorrilonite (MTM) materials. The morphology of the collected residues after flammability testing is investigated. In addition, thermal and thermo-oxidative stability are evaluated by thermogravimetric analyses performed in inert (nitrogen) and oxidative (air) atmospheres. Physical and chemical mechanisms are identified and related to the unique nanostructure and its low thermal conductivity, high gas barrier properties and CNF/MTM interactions for char formation.

To date, heat conduction from heat sources to tissue has been estimated by complex mathematical modeling. In the present study, we developed an intuitive in vitro skin burn model that illustrates heat conduction patterns inside the skin. This was composed of tightly compressed thermal papers with compression frames. Heat flow through the model left a trace by changing the color of thermal papers. These were digitized and three-dimensionally reconstituted to reproduce the heat conduction patterns in the skin. For standardization, we validated K91HG-CE thermal paper using a printout test and bivariate correlation analysis. We measured the papers' physical properties and calculated the estimated depth of heat conduction using Fourier's equation. Through contact burns of 5, 10, 15, 20, and 30 seconds on porcine skin and our burn model using a heated brass comb, and comparing the burn wound and heat conduction trace, we validated our model. The heat conduction pattern correlation analysis (intraclass correlation coefficient: 0.846, p 0.001) and the heat conduction depth correlation analysis (intraclass correlation coefficient: 0.93, p 0.001) showed statistically significant high correlations between the porcine burn wound and our model. Our model showed good correlation with porcine skin burn injury and replicated its heat conduction patterns.

Part 1: This paper presents results of a study with the following objectives: 1. Determine the effects of transport and placement conditions on the inital density of the insulation; 2) Establish a standardized method for producing specimens of blown cellulose fiber insulations; 3) Investigate the factors that cause the material to settle after placement; 4) Establish a standardized method to produce settlement in the specimens comparable with those found in field studies. A method recommended for producing settlement in the specimens consists of two procedures, one simulating settlement by impact produced on the standardized containers, and the other causing settlement under climatic cycling of the material. Part 2: The thermal resistance of a number of commercial blown loose-fill cellulose fiber thermal insulations has been measured using the guarded hot plate and heat flow meter methods. An equation describing the variation of thermal resistance with temperature, temperature difference, density, and thickness has been derived from these measurements and, with lesser precision, from the data provided by other investigators. The equation does not include the effects of chemical content, moisture content, chemical composition, or structure of the paper particles. The thermal resistance of a layer of insulation was found not to be directly proportional to thickness. The equation for thermal resistance fits the National Research Council of Canada (NRC) data with a standard deviation of less than 3.5 percent for thickness of 50 to 305 mm., Thermal Transmission Measurements of Insulation : Symposium: 19 September 1977, Philadelphia, PA., USA