Bonded Joints in Water-Repellent Timber Structures

2016 ◽  
Vol 714 ◽  
pp. 3-9
Author(s):  
Jana Daňková ◽  
Tereza Majstríková ◽  
Pavel Mec
Keyword(s):  
Flame Retardants ◽  
Water Repellent ◽  
Bonded Joints ◽  
Timber Structures ◽  
Degradation Processes ◽  
Knowledge Based ◽  
Treatment Technologies ◽  
Physical And Chemical ◽  
Gaseous Form ◽  
Main Factor

Water in liquid and gaseous form is the main factor which significantly affects degradation processes in the wood. The mechanism and rate of wooden degradation processes can be effectively influenced by appropriate methods and technologies for its protection. However new knowledge, based on the possibilities of application of modern physical and chemical analytical methods, confirms that most well-known and previously commonly used protective equipment damages wooden structure. Many chemical substances, which are included in preservatives such as organic and inorganic biocides, or also flame retardants, are declared to be environmentally unacceptable. Nowadays, environmentally friendly treatment technologies of wood have increased attention to the above reasons. Wooden treatment by silicones ranks among the technologies which repellent, fire resistant and corrosion effectiveness is demonstrated by many authors. This article presents results of the experimental study that deals with the mechanical properties of bonded joints in the wood treated by silicones.

Flammability properties of fire-retardant timber

2021 ◽  
Vol 30 (2) ◽  
pp. 23-34
Author(s):  
O. N. Korolchenko ◽  
S. G. Tsarichenko ◽  
N. I. Konstantinova
Keyword(s):  
Mass Loss ◽  
Flame Propagation ◽  
Flame Retardants ◽  
Fire Retardant ◽  
Combustion Products ◽  
Timber Structures ◽  
Measurement Instruments ◽  
Pine Tree ◽  
Smoke Generation ◽  
Oak Tree

Introduction. At present, the house-building industry, that produces timber structures, is in the process of sufficiently intensive development; however, high flammability of wood is the factor that restrains widespread use of timber in construction. The purpose of this work is to optimize the conditions of application of fire-retardant timber in the construction industry. The co-authors believe that the following problems are to be solved to attain this objective:● a comparative analysis of the fireproofing efficiency of several fire-proofing agents applied to different species of wood;● determination of the character of influence produced by fire proofing agents on fire retardant properties of wood.Methods of research. The fire proofing efficiency of sample compositions designated for wood was measured in compliance with the benchmark testing method specified in GOST R 53292 (p. 6.2). Experiments were launched pursuant to the methodology and with the help of measurement instruments specified in GOST 30244–94 (Method 2) to study the extent of the pine-tree timber flammability suppression. Critical values of thermal loads that may trigger inflammation and flame propagation in timber structures, that can be described using values of the critical surface density of the heat flow, were determined pursuant to GOST 30402–96 and GOST R 51032–97. The toxicity of combustion products and the smoke generation ability of fire-retardant pine-tree samples was assessed using standard methods and measurement instruments pursuant to GOST 12.1.044–89 (paragraphs 4.18 and 4.20).Research results and discussion. Biological flame retardants, integrated biological flame retardants that also ensure moisture protection, intumescent coatings, lacquers and varnishes that are ready for use and labelled as having group I and II fire-retardant efficiency pursuant to GOST R 53292, were studied in the course of this research project. The co-authors have identified that the mass loss by all fire-retardant compositions is below 9 %, if applied to samples of larch and oak-tree timber, same as if it were applied to standard samples of pine-tree timber.The findings of the experiment conducted to assess the flammability, ignitibility, flame propagation, smoke generation ability and toxicity of combustion products have proven the maximal efficiency of the composition designated for full-cell pressure impregnation of timber that ensures the properties of the material labelled as G1, V1, RP1, T2, D2.Conclusions. Hence, the research results have enabled the co-authors to assess the discrepancy between average mass loss values demonstrated by the samples of different species of timber (alder, linden, pine-tree, larch, and oak-tree).The comprehensive study of flammability properties of timber, treated by compositions that vary in their chemical composition and mode of action of the fire proofing agent, enabled the co-authors to identify the impact produced by versatile fire-proofing agents on different flammability properties of pine-tree timber with regard taken of the fire-safe use of construction materials and constructions of buildings and structures.

A Vector Normalized Method-Assisted 3D-QSA2R Model and Its Application in the Molecular Modification of PCBs with Higher Flame Retardancy and Lower Toxicity

2021 ◽  
Vol 13 (1) ◽  
pp. 80-87
Author(s):  
Minghao Li ◽  
Yu Li
Keyword(s):  
Flame Retardancy ◽  
Flame Retardants ◽  
Polychlorinated Biphenyl ◽  
Three Dimensional ◽  
Predictive Ability ◽  
Energy Functional ◽  
Long Distance ◽  
Molecular Modification ◽  
And Control ◽  
Physical And Chemical

Flame retardants are widely used in many materials and products, and there is a pressing need to enhance the performance of flame retardants while lowering their toxicity. In this paper, using polychlorinated biphenyl flame retardants as an example, a three-dimensional quantitative structure-double-activity relationship (3D-QSA2R) model, with the double activities of flame retardancy and toxicity, was constructed by introducing a vector normalized method to achieve the goal of environmental risk management and control the sources of chemicals. The results showed that the 3D-QSA2R model has good robustness and strong predictive ability. PCB-209 was used as a target molecule for the contour map analysis and molecular modification. The comprehensive values (C) of six novel PCB-209 molecules were increased by up to 53.61%. The physical and chemical parameters (frequency and Gibbs free energy), functional properties (stability and insulation) and the other three POP properties of the novel PCB-209 molecules showed that the Cl atom substitution reaction of PCB209 molecules could occur and exist stably in the environment. With improvement in stability, the insulation of six novel PCB-209 molecules was not influenced after modification, and the environmental persistence, bioconcentration and long-distance migration of six novel PCB-209 molecules were increased up to 99.47%, 15.29% and 100.9%, respectively. The flame retardancy and toxicity of the new molecules were verified by Gaussian software and the EPI database, respectively. The single activity verification values of flame retardancy and toxicity followed the trend of C values predicted by the double-activity 3D-QSA2R model established in this paper. The ratio between the two single activities of the new PCB-209 molecule generally conformed to the weight setting, which satisfies the purpose of setting the weight as the main way to improve the efficacy of flame retardants.

scholarly journals Pretreatment of Lignocelollusic Biomass Based on Improving Enzymatic Hydrolysis

2017 ◽  
Vol 5 (1) ◽  
pp. 1-11 ◽  
Author(s):  
Meysam Madadi ◽  
Yuanyuan Tu ◽  
Aqleem Abbas
Keyword(s):  
Alternative Energy ◽  
Treatment Method ◽  
Accessible Surface Area ◽  
Effective Parameters ◽  
Sugar Degradation ◽  
Treatment Technologies ◽  
Pre Treatment ◽  
Accessible Surface ◽  
Alternative Energy Resources ◽  
Physical And Chemical

Lignocellulosic materials among the alternative energy resources are the most desirable resources that can be employed to produce cellulosic ethanol, but this materials due to physical and chemical structure arranges strong native recalcitrance and results in low yield of ethanol. Then, a proper pre-treatment method is required to overcome this challenge. Until now, different pre-treatment technologies have been established to enhance lignocellulosic digestibility. This paper widely describes the structure of lignocellulosic biomass and effective parameters in pre-treatment of lignocelluloses, such as cellulose crystallinity, accessible surface area, and protection by lignin and hemicellulose. In addition, an overview about the most important pre-treatment processes include physical, chemical, and biological are provided. Finally, we described about the inhibitors enzymes which produced from sugar degradation during pre-treatment process and the ways to control this inhibitors.Int. J. Appl. Sci. Biotechnol. Vol 5(1): 1-11

scholarly journals Probability timed automata for investigating communication processes

2015 ◽  
Vol 25 (2) ◽  
pp. 403-414
Author(s):  
Henryk Piech ◽  
Grzegorz Grodzki
Keyword(s):  
Timed Automata ◽  
Security Analysis ◽  
Irreversible Processes ◽  
Protocol Security ◽  
Degradation Processes ◽  
Communication Processes ◽  
Main Factor

Abstract Exploitation characteristics behaves as a decreasing valors factor (DVF) which can be connected with degradation processes. It is a structure that consists of independent attributes which represent situations generally connected with a given exploitation factor. The multi-attribute structure contains attributes directly and indirectly referring to the main factor. Attribute states, by definition, can only maintain or decrease their values. Such situations are met in security, reliability, exploitation, fatigues and many complex one-directed or irreversible processes. The main goal refers to protocol security analysis during the realization of the communication run that specifies the assessment of the level of current and oncoming threats connected with cryptography authentication. In the communication run, the operations of different protocols mutually interleave. Our concept is based on the algorithm of attributes correction during exploitation process realization (Blanchet et al., 2008). The monitoring and correcting procedures make it possible to provide forecast information about possible threats on the basis of the structure of the current attribute values.

Protecting our Great Lakes: assessing the effectiveness of wastewater treatments for the removal of chemicals of emerging concern

2014 ◽  
Vol 49 (1) ◽  
pp. 23-31 ◽  
Author(s):  
Antonette Arvai ◽  
Gary Klecka ◽  
Saad Jasim ◽  
Henryk Melcer ◽  
Michael T. Laitta
Keyword(s):  
Wastewater Treatment ◽  
Great Lakes ◽  
Flame Retardants ◽  
Municipal Wastewater ◽  
Wastewater Treatment Plants ◽  
Water System ◽  
Municipal Wastewater Treatment ◽  
International Joint Commission ◽  
Treatment Technologies ◽  
Municipal Wastewater Treatment Plants

The Great Lakes and their connecting channels form the largest fresh surface water system on earth. Over the past 10 years, focus on environmental monitoring has shifted to an array of recently discovered compounds known as ‘chemicals of emerging concern’ (CEC). These chemicals are found in products used daily in households, businesses, agriculture and industry, such as flame retardants, pharmaceuticals, personal care products, and pesticides. Wastewater treatment plants are among the important pathways by which CEC enter the Great Lakes, with concentrations highest in the vicinity of wastewater discharges. Treated sewage is often discharged into the nearshore waters, which also provide a source of drinking water to the public. In 2009–2011, the International Joint Commission addressed the need to assess the effectiveness of existing wastewater treatment technologies in the basin to remove CEC, as well as to gain insight on potential advanced technologies to improve their removal. This assessment encompassed three major activities, development of an inventory of municipal wastewater treatment plants that discharge in the basin; a survey of detailed operational data for selected wastewater facilities; and a comprehensive literature review and analysis of the effectiveness of various wastewater treatment technologies to remove chemicals of emerging concern.

scholarly journals Establishing patterns of mass transfer under the action of water on the hydrophobic coating of the fire-retardant element of a tent

2021 ◽  
Vol 4 (10(112)) ◽  
pp. 45-51
Author(s):  
Yuriy Tsapko ◽  
Zinovii Sirko ◽  
Roman Vasylyshyn ◽  
Oleksandr Melnyk ◽  
Аleksii Tsapko ◽  
...  
Keyword(s):  
Mass Transfer ◽  
Fire Protection ◽  
Flame Retardants ◽  
Fire Retardant ◽  
Protective Layer ◽  
Water Repellent ◽  
Water Penetration ◽  
Hydrophobic Coating ◽  
Study Results ◽  
Fabric Surface

This paper reports an analysis of the flame retardants for fabrics that has revealed the fact that the meagerness of data to explain and describe the process of fire protection, specifically the neglect of elastic coatings, leads to that the structures made from fabrics are ignited under the influence of a flame. Devising reliable methods to study the fire protection conditions for fabrics results in the design of new types of fireproof materials. Therefore, there is a need to determine the conditions for the formation of a barrier for water mass transport and to establish a mechanism for slowing down water penetration through the material. In this regard, an estimation-experimental method has been constructed for determining mass transfer under the action of water when using a hydrophobic coating, which makes it possible to assess water penetration. Based on the experimental data and theoretical dependences, the intensity of mass flow under the action of water has been determined, which is 0.000177 kg/m2, which ensures fabric resistance. The study results have proven that the process of waterproofing the fabric involves inhibition of the mass transfer process under the action of water by insulating the surface of the fireproof fabric with a hydrophobic coating. It should be noted that the presence of a hydrophobic coating leads to blocking the fabric surface from moisture penetration. Such a mechanism behind the effect of the hydrophobic coating is likely the factor in adjusting the process through which the integrity of an object is preserved. Thus, the sample of fireproof fabric coated with a water repellent demonstrated, after exposure to water, that the amount of water absorbed did not exceed 0.00012 kg, and, for a fabric without a water repellent, was 0.01 kg. Thus, there is reason to assert the possibility of targeted adjustment of the processes related to water penetration of the fabric by using hydrophobic coatings that could form a protective layer on the surface of the material, which inhibits the rate of water penetration.

Effect of Calcined-Bauxite Quality and Secondary Mullitization Reaction on Firing and Properties of Ceramic Plates

2019 ◽  
Vol 960 ◽  
pp. 207-213
Author(s):  
Li Biao Xiao ◽  
Xiao Qing Hua ◽  
Qun Hu Xue
Keyword(s):  
High Temperature ◽  
Water Absorption ◽  
High Water ◽  
Linear Shrinkage ◽  
Modulus Of Rupture ◽  
Ceramic Plate ◽  
High Temperature Reaction ◽  
Low Modulus ◽  
Physical And Chemical ◽  
Main Factor

Addition of different types of calcined bauxites to the ceramic plate formulation was performed to study effects on the firing and properties of the resulting ceramic plates. The physical and chemical characteristics, high-temperature reaction degree, thermochemical behavior, mineral composition, and microstructure of the calcined bauxites were analyzed. The results showed that lightly calcined bauxite could minimize the linear shrinkage rate. However, incomplete high-temperature secondary mullitization reaction could inhibit completion of product sintering and result in a loose microstructure, high water absorption index, and low modulus of rupture. Application of GAL-85 high-temperature calcined bauxite yielded a product with good sintering performance and low water absorption; increased amounts of mullite reinforcement phase also increased the strength of the plate. The degree of secondary mullitization was the main factor affecting the performance of the ceramic plate.

scholarly journals Kualitas dan distribusi spasial karakteristik fisika-kimia Sungai Siak di Kota Pekanbaru

DEPIK ◽  
2020 ◽  
Vol 9 (2) ◽  
pp. 335-343
Author(s):  
Luri Anita Vanri ◽  
Adriman Adriman ◽  
Muhammad Fauzi
Keyword(s):  
Water Quality ◽  
Fecal Coliform ◽  
Principal Component ◽  
Ex Situ ◽  
Chemical Parameters ◽  
Physical And Chemical Parameters ◽  
Physical And Chemical ◽  
Main Factor

Siak River is one of the biggest rivers and the deepest in Riau Province in Indonesia with its 20-30 depth and depth 370 kilometers. The Siak River used for bathing, washing, dumping industrial palm oil, plantation, domestic waste, and port so it has an impact on water quality changing. This study analyzed the water quality and distribution spatial physical and chemical parameters the river around in Pekanbaru city, using Principal Component Analysis (PCA), this study used laboratory in situ and ex situ water quality measurement instruments. Water sampling each station done three times in two weeks during October to November 2019. The results obtained from this study shows the water quality of these 6 stations in the category of bad and the water quality from headwaters to downstream river influenced by organic parameter as a dominant pollutant. The correlation of water quality characteristic was 74.4% main factor 1 (F1) 47.4% and main factor 2 (F2) 26.7% with main characteristics fecal coliform, phosphate, and nitrate. Grouping these characteristics through a dendrogram showed three levels of relationship based on the characteristic parameter. The first group stands for station 1,2, and 4 have higher brightness and Dissolved oxygen (DO) parameters than other stations. The second group stands for stations 3 and 5 that have relatively high in parameter phosphate and nitrate. The third group is station 6 (river estuary) which results in shows high of fecal coliform proportional to pollution. The study can be concluded that three groups heavily contaminated. Each group has different parameters that show influence upland and waters activities.Keywords: Distribution of spatial, The quality of water, Siak River, Physical and Chemical Parameters, PCA ABSTRAKSungai Siak merupakan salah satu sungai terbesar di Provinsi Riau dan terdalam di Indonesia, dengan kedalaman sekitar 20-30 meter dan panjang 300 kilometer. Sungai siak masih dimanfaatkan oleh masyarakat sebagai sarana Mandi Cuci Kakus (MCK), tempat buangan limbah industri kelapa sawit, perkebunan, rumah tangga dan pelabuhan, sehingga berdampak pada perubahan kualitas perairan. Penelitian dilakukan untuk menganalisa kualitas dan distribusi spasial karateristik fisik-kimia perairan Sungai Siak di sekitar Kota Pekanbaru, dengan menggunakan Principal Component Analysis (PCA). Kajian menggunakan instrument pengukuran kualitas air in situ dan ex situ di laboratorium. Pengambilan sampel air pada masing-masing stasiun dilakukan sebanyak tiga kali setiap dua minggu selama bulan Oktober hingga November 2019. Hasil yang diperoleh dari kajian ini adalah kualitas air di keenam stasiun masuk dalam katagori buruk dan mengalami penurunan kualitas dari hulu ke hilir yang disebabkan bahan organik. Korelasi karakteristik kualitas air sebesar 74,3%, faktor utama 1 (F1)  47,4% dan faktor utama 2 (F2) 26,7% dengan penciri utama fecal coliform, fosfat dan nitrat. Pengelompokan stasiun pada dendogram klarifikasi hierarki menunjukkan adanya tiga tingkat hubungan kekerabatan berdasarkan parameter pencirinya. Kelompok satu terdiri dari stasiun 1, 2 dan 4 memiliki hasil relatif tinggi pada parameter kecerahan dan oksigen terlarut (DO) dibandingkan dengan stasiun lainnya. Kelompok dua terdiri dari stasiun 3 dan 5 memiliki hasil relatif tinggi pada paramter nitrat dan fosfat dibandingkan dengan stasiun lainnya. Kelompok tiga adalah stasiun 6 (muara sungai sail) dengan parameter fecal coliform relatif tinggi yang berbanding lurus dengan tingkat pencemarannya. Berdasarkan hasil kajian dapat disimpulkan bahwa tiga kelompok sama-sama tercemar berat, namun masing-masing kelompok memiliki perbedaan parameter pencirinya yang memperlihatkan pengaruh berbagai aktifitas di darat maupun di perairan itu sendiri.Kata kunci: Distribusi spasial, Kualitas air, Sungai Siak, Parameter fisika dan kimia, PCA

scholarly journals Identification of Dextran and Sludge–Producing Bacteria in Sugar Cane Juices Using Polymerase Chain Reaction

2017 ◽  
Vol 14 (4) ◽  
pp. 1337-1341
Author(s):  
Farzam Latifi ◽  
Sirous Chehrazi ◽  
Hossein Ansari
Keyword(s):  
Polymerase Chain Reaction ◽  
Cross Sectional Study ◽  
Cane Sugar ◽  
Chain Reaction ◽  
Cross Sectional ◽  
Chemical Washing ◽  
Polymerase Chain ◽  
Physical And Chemical ◽  
Main Factor

ABSTRACT: The microbial contamination due to cane sugar transition to the mills is one of the most important factors in increasing sugar lesions in the factory. This study was aimed to isolate dextran-producing bacteria and determine their genus and species. It is a descriptive cross-sectional study which was conducted in year 2014. For this purpose, 200 samples were collected from sugarcane syrups, and then cultured as pourplate and surface. The bacteria were counted and the DNA extracted from the purified bacteria according to the kit protocol. Then, determination of the genus and species of dextran-producing bacteria was performed by polymerase chain reaction (PCR) using specific primers. Data obtained from biochemical, microbial and PCR showed that around 80 strains of leuconostoc have been detected in samples. The results of this study indicate that leuconostoc mesenteroides is the main factor in the production of dextran in sugarcane and beet manufactories. The above mentioned contamination sources can be minimized by reducing the transfer time of burned sugarcane to the factory, as well as the regular physical and chemical washing of the mills.

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