Добірка наукової літератури з теми "Protection against moisture"
Оформте джерело за APA, MLA, Chicago, Harvard та іншими стилями
Ознайомтеся зі списками актуальних статей, книг, дисертацій, тез та інших наукових джерел на тему "Protection against moisture".
Біля кожної праці в переліку літератури доступна кнопка «Додати до бібліографії». Скористайтеся нею – і ми автоматично оформимо бібліографічне посилання на обрану працю в потрібному вам стилі цитування: APA, MLA, «Гарвард», «Чикаго», «Ванкувер» тощо.
Також ви можете завантажити повний текст наукової публікації у форматі «.pdf» та прочитати онлайн анотацію до роботи, якщо відповідні параметри наявні в метаданих.
Статті в журналах з теми "Protection against moisture":
1
Delaporte, Nicolas, Michel L. Trudeau, Daniel Bélanger, and Karim Zaghib. "Protection of LiFePO4 against Moisture." Materials 13, no. 4 (February 20, 2020): 942. http://dx.doi.org/10.3390/ma13040942.
Анотація:
In this study, a carbon-coated LiFePO4 (LFP/C) powder was chemically grafted with trifluoromethylphenyl groups in order to increase its hydrophobicity and to protect it from moisture. The modification was carried out by the spontaneous reduction of in situ generated 4-trifluoromethylphenyl ions produced by the diazotization of 4-trifluoromethylaniline. X-ray photoelectron spectroscopy was used to analyze the surface organic species of the modified powder. The hydrophobic properties of the modified powder were investigated by carrying out its water contact angle measurements. The presence of the trifluoromethylphenyl groups on the carbon-coated LiFePO4 powder increased its stability in deionized water and reduced its iron dissolution in the electrolyte used for assembling the battery. The thermogravimetric and inductively coupled plasma atomic emission spectroscopy analyses revealed that 0.2–0.3 wt.% Li was deinserted during grafting and that the loading of the grafted molecules varied from 0.5 to 0.8 wt.% depending on the reaction conditions. Interestingly, the electrochemical performance of the modified LFP/C was not adversely affected by the presence of the trifluoromethylphenyl groups on the carbon surface. The chemical relithiation of the grafted samples was carried out using LiI as the reducing agent and the lithium source in order to obtain fully lithiated grafted powders.
2
Storodubtseva, Tamara, Andrey Milyaev-, and E. Volobuev. "Protection of the wood reinforcing zapolniyel against moisture influence." Актуальные направления научных исследований XXI века: теория и практика 3, no. 9 (December 9, 2015): 90–94. http://dx.doi.org/10.12737/16439.
3
Struhárová, Alena. "Chemical Grouting Method and its Effectiveness for Protection of Autoclaved Aerated Concrete Masonry." Advanced Materials Research 923 (April 2014): 112–16. http://dx.doi.org/10.4028/www.scientific.net/amr.923.112.
Анотація:
Protection of masonry and constructions of buildings against water and moisture is an important part of building industry. Contribution deals with problems of moisture, its classification and moisture level on the constructions. The chemical grouting method for protection of autoclaved aerated concrete masonry against capillary moisture via treatment by using the hydrophobic grouting solution Freezteq DPC System is described in this contribution.
4
Sedlmajer, Martin, Jiri Zach, and Jitka Peterková. "Development of Masonry Components Protected against Moisture." Advanced Materials Research 860-863 (December 2013): 1248–51. http://dx.doi.org/10.4028/www.scientific.net/amr.860-863.1248.
Анотація:
During construction process and life, a number of negative influences can have effect on masonry structures; moisture, which is undesirable in the masonry, can be one of such influences. The lower area of the masonry (plinth walling) is strained the most by the moisture. The paper deals with potential reduction of the effect of moisture in places, where the masonry structure is founded, through hydrophobization of walling units. Such solution of the issue of protection of the building structure against the influence of humidity should not have negative effect on the resulting masonry parameters, particularly not on the potential application of surface treatment materials. The collective influence of the surface treatment materials, consisting usually of plaster, and the actual masonry should be ensured.
5
Chmielewski, Ryszard, and Paweł Muzolf. "Selected problems of protection of historic buildings against the rainwater and the groundwater." MATEC Web of Conferences 174 (2018): 03012. http://dx.doi.org/10.1051/matecconf/201817403012.
Анотація:
The paper presents selected problems in the selection of the state of the art modern civil engineering solutions for drying moisture or wet, in particular parts of the underground structures of the brick historic buildings. The repair works of the immobile cultural heritage civil engineering objects require the appropriate choice of the design solution. These should be achieved by obtaining the assumed effects in the form of the effectiveness of repairs regarding all possible measures of protection of the cultural heritage buildings. Another key issue of the analysis of the causes of moisture formation in underground masonry structures is the necessity of consideration of the historic character of these buildings. Based on authors' extensive experience and expert knowledge, a range of diagnostics process as well as the assessment of the causes of the moisture problems of historic buildings for several selected cases was proposed. Moisture is transferred from the outside of the building to the basement interior by four mechanisms liquid water flow, capillary suction, vapor diffusion and air movement. The variety of the different mechanisms of moisture transfer, especially regarding buildings of cultural heritage implies that the selection of the most suitable system solution for solving moisture problem is the most crucial and a key issue in a specific case.
6
Semko, O. V., N. M. Mahas, A. R. Mishchenko, and R. R. Mishchenko. "MOISTURE EFFECTS ON THE BUILDINGS ENCLOSING STRUCTURES." ACADEMIC JOURNAL Series: Industrial Machine Building, Civil Engineering 1, no. 50 (April 11, 2018): 278–84. http://dx.doi.org/10.26906/znp.2018.50.1086.
Анотація:
Analysis of the most common damages due to moisture effects on brick, reinforced-concrete and wooden buildings enclosing structures has been carried out. Causes of their occurrence and prevention ways have been analyzed. The most dangerous moisture types such as constructional, soil, atmospheric, operational, hygroscopic and condensed have been outlined. Measures to ensure protection against water-saturation of building elements such as eaves size, walls waterproofing, available airways, protective painting, hydrophobic impregnation, sufficient ventilation, heating, water supply systems and draining timely repairs have been recommended.
7
Leskela, Markku, Emma Salmi, and Mikko Ritala. "Atomic Layer Deposited Protective Layers." Materials Science Forum 879 (November 2016): 1086–92. http://dx.doi.org/10.4028/www.scientific.net/msf.879.1086.
Анотація:
This paper reviews the use of Atomic Layer Deposition (ALD) in protective coatings. Because of the growth principle ALD allows the deposition of dense conformal films on substrates of different size and shape. Recently, ALD has received increasingly interest in deposition of protective coatings. In protective coatings oxides are the most common materials and especially Al, Ti, and Ta oxides have been applied. The use of nanolaminates enables improving the protection properties. Since ALD films are pinhole-free and often thin they are used to protect against moisture, radiation, out-gassing but not often against corrosion of metals. Very good moisture barriers are obtained with thin ALD oxide layers on polymers and cardboard. This property is also very attractive in encapsulation of OLEDs. In studies of energy technology materials protection of electrodes in Li-ion batteries, fuel cells and supercapacitors by ALD has been reported and significant improvement in the stability has been achieved. Yet another area is protection of silver jewelry from tarnishing by a thin oxide layer. In traditional corrosion protection of metals ALD films have proven to be useful in tailoring of interfaces and sealing of defects in coatings made by other techniques.
8
Tsapko, Yuriy, Oleksandra Horbachova, Serhii Mazurchuk, Аleksii Tsapko, Kostiantyn Sokolenko, and Andrii Matviichuk. "Establishing regularities of wood protection against water absorption using a polymer shell." Eastern-European Journal of Enterprise Technologies 1, no. 10(115) (February 25, 2022): 48–54. http://dx.doi.org/10.15587/1729-4061.2022.252176.
Анотація:
This paper has analyzed protective materials for timber building structures and established the need to devise reliable methods for studying the process of water absorption by the surface of the construction structure necessary for designing new types of fire-retardant materials. Therefore, it becomes necessary to determine the conditions for the formation of a barrier for water absorption and to elucidate a mechanism for inhibiting the transfer of moisture to the material. In this regard, a mathematical model of the intensity of water mass transfer when using a polymer shell made of organic material as a coating has been built, which makes it possible to assess the effectiveness of the polymer shell by the amount of water absorbed. Based on the experimental data and theoretical dependences, the intensity of absorption of water by wood was calculated; and it has been established that the protective coating reduces the amount of water absorbed by more than 20 times. The results of determining the weight gain by a sample during water exposure indicate an ambiguous impact of the nature of protection on water absorption. In particular, this implies the presence of data sufficient for the qualitative process of inhibition of moisture diffusion; and detecting, on its basis, the point in time when the drop in the coating's efficiency begins. Analysis of the results of experiments reveals that the maximum increase in mass in the case of water absorption by a non-treated sample of wood was 40 % while the increase in the mass of wood samples treated with mixtures of oil and paraffin was less than 28 %. At the same time, the best protection is shown by a mixture of oil with paraffin within 90÷95 %. Thus, there are grounds to assert the possibility of directed regulation of wood protection processes through the use of polymer coatings that can form a protective layer on the surface of the material, which inhibits the rate of absorption of water.
9
Jussila, Kirsi, Sirkka Rissanen, Kai Parkkola, and Hannu Anttonen. "Evaluating Cold, Wind, and Moisture Protection of Different Coverings for Prehospital Maritime Transportation–A Thermal Manikin and Human Study." Prehospital and Disaster Medicine 29, no. 6 (October 31, 2014): 580–88. http://dx.doi.org/10.1017/s1049023x14001125.
Анотація:
AbstractIntroductionPrehospital maritime transportation in northern areas sets high demands on hypothermia prevention. To prevent body cooling and hypothermia of seriously-ill or injured casualties during transportation, casualty coverings must provide adequate thermal insulation and protection against cold, wind, moisture, and water splashes.ObjectiveThe aim of this study was to determine the thermal protective properties of different types of casualty coverings and to evaluate which would be adequate for use under difficult maritime conditions (cold, high wind speed, and water splashes). In addition, the study evaluated the need for thermal protection of a casualty and verified the optimum system for maritime casualty transportation.MethodsThe study consisted of two parts: (1) the definition and comparison of the thermal protective properties of different casualty coverings in a laboratory; and (2) the evaluation of the chosen optimum protective covering for maritime prehospital transportation. The thermal insulations of ten different casualty coverings were measured according to the European standard for sleeping bags (EN 13537) using a thermal manikin in a climate chamber (-5°C) with wind speeds of 0.3 m/s and 4.0 m/s, and during moisture simulations. The second phase consisted of measurements of skin and core temperatures, air temperature, and relative humidity inside the clothing of four male test subjects during authentic maritime prehospital transportation in a partially-covered motor boat.ResultsWind (4 m/s) decreased the total thermal insulation of coverings by 11%-45%. The decrement of thermal insulation due to the added moisture inside the coverings was the lowest (approximately 22%-29%) when a waterproof reflective sheet inside blankets or bubble wrap was used, whereas vapor-tight rescue bags and bubble wrap provide the most protection against external water splashes. During authentic maritime transportation lasting 30 minutes, mean skin temperature decreased on average by 0.5°C when a windproof and water-resistant rescue bag was used over layered winter clothing.ConclusionThe selected optimum rescue bag consisted of insulating and water-resistant layers providing sufficient protection against cold, wind, and water splashes during prehospital transportation lasting 30 minutes in the uncovered portion of a motor boat. The minimum thermal insulation for safe maritime transportation (30 minutes) is 0.46 m2K/W at a temperature of -5°C and a wind speed of 10 m/s.JussilaK, RissanenS, ParkkolaK, AnttonenH. Evaluating cold, wind, and moisture protection of different coverings for prehospital maritime transportation–a thermal manikin and human study. Prehosp Disaster Med. 2014;29(6):1-9.
10
Muhammad, Bening Tirta, Viktor Barát, Teck Ming Koh, Xihu Wu, Abhijith Surendran, Natalia Yantara, Annalisa Bruno, Andrew C. Grimsdale, Mihaiela C. Stuparu, and Wei Lin Leong. "Novel amphiphilic corannulene additive for moisture-resistant perovskite solar cells." Chemical Communications 56, no. 80 (2020): 11997–2000. http://dx.doi.org/10.1039/d0cc04043f.
Анотація:
Novel triethyleneglycol-functionalized corannulene sulfone (Cor-TEG) with by-design functionalities leads to favourable perovskite morphology, enhanced carrier extraction and protection against moisture.
Дисертації з теми "Protection against moisture":
1
Золотов, Микита Юрійович. "Обґрунтування сучасних гідроізоляційних систем для підвищення довговічності та якості будівельної продукції". Магістерська робота, 2021. https://dspace.znu.edu.ua/jspui/handle/12345/6582.
Анотація:
Золотов М. Ю. Обґрунтування сучасних гідроізоляційних систем для підвищення довговічності та якості будівельної продукції : кваліфікаційна робота магістра спеціальності 192 «Будівництво та цивільна інженерія» / наук. керівник Н. О. Данкевич. Запоріжжя : ЗНУ, 2021. 109 с.UA : В роботі проаналізовано і досліджено сучасний стан використання гідроізоляційних матеріалів для захисту будівельних конструкцій, що дає можливість підвищити сфери застосування. Розглянуті види та типи гідроізоляційних систем в залежності від умов експлуатації, технічних і економічних чинників та її конструктивно-технологічне вирішення. Досліджені і приведені існуючі критерії оцінки ефективності застосування гідроізоляційних систем, а також зроблено акцент на використані гідроізоляцій проникаючої дії, із полімерних мембран та СБС модифікованих рулонних матеріалів, які частково усувають недоліки їх аналогів та забезпечують поліпшення якості захисту конструкцій, підвищують якість виконання робіт, знижують трудомісткості процесу та собівартості виконання робіт.
EN : The modern state of the use of hydraulic insulating materials is in-process analysed and investigational for defence of building constructions, that gives an opportunity to promote application domains. Considered kinds and types of the waterproofing systems depending on external, technical and economic factors environments and her structurally-technological decision. Investigational and resulted existent criteria of estimation of efficiency of application of the waterproofing systems, and also an accent is done on used waterproofing of penetrating action, from polymeric membranes and SBS of the modified roll materials, that partly remove the lacks of their analogues and provide the improvement of quality of defence of constructions, promote quality of implementation of works, reduce to labour intensiveness of process and prime price of implementation of works.
Частини книг з теми "Protection against moisture":
1
Salahuddin, B. "Durability Against Fatigue and Moisture of Natural Fibre Composite." In Materials Research Foundations, 128–53. Materials Research Forum LLC, 2022. http://dx.doi.org/10.21741/9781644901854-6.
Анотація:
The development of high-performing engineering materials fabricated using constituents of natural origins is gradually increasing around the globe. In the last few decades, there have been notable research achievements in green materials science through the development of natural fibre reinforced composites (NFCs). The advantages of these materials over synthetic fibre composites support extensive range of potential applications, with added benefits of low environmental impact and inexpensive throughput. Significant effort has gone into improving their performance to extend the capabilities and applications of this materials. Although there is a range of performance limitations which can be seen from NFCs, durability against fatigue and moisture of these materials are amongst the major concerns. This chapter aims to provide an overview of the effects of fatigue and moisture on NFCs by discussing factors, testing technology and protection techniques, and their effect on the durability and performance of the composites.
2
Conway, Gordon, Ousmane Badiane, and Katrin Glatzel. "Sustainable Agriculture." In Food for All in Africa, 107–29. Cornell University Press, 2019. http://dx.doi.org/10.7591/cornell/9781501743887.003.0006.
Анотація:
This chapter proposes that the way forward will be a prosperous and sustainable agriculture sector deeply rooted in the concept of sustainable intensification (SI): producing more with less, using inputs like seeds, fertilizers, and pesticides more prudently, adapting to climate change, reducing GHG emissions, improving natural capital such as soil moisture capacity and the diversity of pests' enemies, and building resilience. One approach to SI is to employ precision agriculture, ensuring that inputs—whether nutrients, pesticides, seeds, or water—are used in a precise, sparing, effective, and strategic way in order to minimize their environmental impact. Thus microdosing permits the prudent, targeted use of inputs such as fertilizers, thereby improving soil quality and moisture while reducing the environmental impact that excessive use can cause. It also reduces costs and helps improve nutrient use efficiency and protection against drought. Precision farming focuses on just one aspect of SI. More generally, it is a concept that includes three mutually reinforcing pillars: ecological intensification, genetic intensification, and socioeconomic intensification.
3
Xu, Kaimeng, Guanben Du, and Siqun Wang. "Wood Plastic Composites: Their Properties and Applications." In Engineered Wood Products for Construction [Working Title]. IntechOpen, 2021. http://dx.doi.org/10.5772/intechopen.98918.
Анотація:
Wood plastic composites (WPCs) is one of crucial and potential engineering wood products that has been extensively employed in the fields of landscape, transportation, municipal engineering and building construction. It has gradually been used to replace the conventional wood-based composites. This chapter aims to introduce the properties and development of WPCs and illustrate how defects in their mechanical properties, biological and aging resistance, and flame retardance affect their global development. Herein, the effects on the biological durability of WPCs against algae, mold, fungi, and termites made with various wood species with different chemical extractive compositions, the natural weathering performance of WPCs and the mechanisms of protection against ultraviolet light and moisture, the effectiveness and mechanism of reinforcement of WPCs by novel alloy modification of linear and aromatic polyamides are reviewed. Additionally, the flame retardance properties, common testing methods as well as the performances of novel flame retardants for WPCs, are comparatively described. Lastly, the limitations and prospects of WPCs in future construction applications are also discussed.
Тези доповідей конференцій з теми "Protection against moisture":
1
Ahmed, Tamseel Murtuza, Zaara Ali, Muhammad Mustafizur Rahman, and Eylem Asmatulu. "Advanced Recycled Materials for Economic Production of Fire Resistant Fabrics." In ASME 2018 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2018. http://dx.doi.org/10.1115/imece2018-88640.
Анотація:
Fire protective clothing is crucial in many applications, in military/government (Navy, Marine Corps, Army, Air Force, Coast Guard, and Law Enforcement) and industry (working with furnaces, casting, machining and welding). Fire resistant clothes provide protection to those who are at risk for exposure to fire hazards (intense heat and flames) and provide inert barrier between the skin and fire and shields the user from direct exposure to fire and irradiation. Flame retardant and chemical protective apparel consumption was 997 million m2 in 2015. This market size expected to grow more due to substantial increase in military and industrial demand. Advanced materials have long history in these areas to protect human life against the hazards. There are two main application techniques for producing fire resistant clothing: 1) Using fire retardant materials directly in the textile, and 2) Spray coating on the garments. Over the time these physically and chemically treated cloths begin to degrade and become less protective due to UV and moisture exposure, abrasion, wear, and laundry effects which will shorten the useful wear life of those cloths. The study compared the improved fire resistance of fabrics when treated with recycled graphene solution.
2
Bordean, Despina-Maria, Aurica Breica Borozan, Gabriel Bujanca, Camelia Cioban, and Delia Gabriela Dumbrava. "EFFECTS OF BOILING AND ROASTING ON CRUDE PROTEINS, TOTAL ANTIOXIDANT CAPACITY AND TOTAL POLYPHENOLS CONTENT OF POTATO TUBERS." In GEOLINKS International Conference. SAIMA Consult Ltd, 2020. http://dx.doi.org/10.32008/geolinks2020/b1/v2/08.
Анотація:
Compared with other sources, potato can bring multiple nutritional benefits because it’s naturally low energy food (0.7 kcal), having high water, fiber and starch content. Even if the consummation of potatoes is in decline, it is still considered a source of valuable nutrition. Depending on the method of preparation, potatoes contain significant level of proteins and antioxidants and can offer considerable protection against cardiovascular diseases and cancer. Natural antioxidants are present under different forms in all plants, being the base source of these compounds for humans. The objective of this study was to determine the moisture content, crude protein, total antioxidant capacity and phenolic content of three assortments of potatoes (Solanum tuberosum) available on the Romanian local market (Timis County). The study was carried out on raw, unpeeled, boiled and roasted potatoes. The moisture content was determinate thermogravimetrically using Sartorius thermo balance, crude protein quantified by using a rapid colorimetric method, total antioxidant capacity determinate using CUPRAC method and total polyphenols content using Folin-Ciocalteu assay. The experimental results show that blue roasted potatoes present the highest content of crude protein, total antioxidant capacity and total polyphenols content and the lowest water content. The obtained data are used to create a graphical fingerprint of raw and processed potatoes in order to identify the best options to mix different potatoes assortments and to create innovative nutritious food products
3
Zimmerman, M. A. "Low Cost Plastic Packaging of the Network Interface Unit." In ASME 1997 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 1997. http://dx.doi.org/10.1115/imece1997-0815.
Анотація:
Abstract The Network Interface Unit is a module of electronics mounted on the side of homes which carries broadband information, including voice, video, and data. The packaging goals are to provide for environmental protection along with EMI shielding for the electronics with inherent reliability’s providing for up to 20 years in life, at extremely low costs. The packaging approach involves providing a double enclosure concept utilizing injection molded plastics. The design provides for snap-fit features which allows for mounting of the printed circuit board and a one-time-only snap-fit of the inside enclosure with no seals, screws, or gaskets to minimize assembly costs. The inside plastic components provide for fire resistance (UL-94-5VA), high heat resistance, and shielding while the outside plastic enclosure provides for chemical resistance, impact resistance, (low temperature) and ultraviolet resistance. The outside enclosure provides for a hinge and skirt which allows for shielding of the internal plastic components against ultraviolet exposure. There is also a tongue and groove seal which provides for moisture resistance.
4
Al-Gunaid, Taghreed Abdulhameed, Anton Popelka, and Igor Krupa. "Enhancement of Adhesion Characteristics of Low-density Polyethylene using Atmospheric Plasma Initiated-Grafting of Polyethylene Glycol." In Qatar University Annual Research Forum & Exhibition. Qatar University Press, 2021. http://dx.doi.org/10.29117/quarfe.2021.0056.
Анотація:
The low-density polyethylene/aluminum (LDPE/Al) joint in Tetra Pak food container provides stability and strength to food packaging, ensures protection against outside moisture, and maintains the nutritional values and flavors of food without the need for additives in the food products. However, it was found that the adhesion strength of LDPE with Al is weak or almost non-existent, due to the non-polar hydrophobic LDPE surface. Therefore, it was necessary to apply surface treatment to LDPE. Plasma-assisted grafting of the LDPE surface with different molecular weight compounds of polyethylene glycol (PEG) was used to improve LDPE/Al adhesion. It was found that this surface modification contributed to significantly improve the wettability of the LDPE surface, as was confirmed by contact angle measurements. The chemical composition changes after plasma treatment and modification process was observed by X-ray photoelectron spectroscopy (XPS) and Fourier transform infrared spectroscopy (FTIR). A surface morphology was analyzed by scanning electron microscopy (SEM) and atomic force microscopy (AFM). Adhesion characteristics of LDPE/Al adhesive joints were analyzed by the peel tests. The most significant adhesion improvement of the PEG modified LDPE surface was achieved using 10.0 wt.% aqueous (6000 M) PEG solution, while the peel resistance increased by approximately 54 times in comparison with untreated LDPE.
5
Purcell, John E. "Preventing Corrosion in Gas Turbine Fuel Systems." In ASME 1997 Turbo Asia Conference. American Society of Mechanical Engineers, 1997. http://dx.doi.org/10.1115/97-aa-014.
Анотація:
Most failures of fuel system components, such as flow dividers and fuel pumps, are caused by the effects of corrosion. Rusting of iron and steel can jam rotating components, while surface pitting of many materials from traces of acids in the fuel can weaken parts. It can be shown that preventing fuel system corrosion can substantially increase the reliability and availability of the gas turbine. Part of the reason that corrosion is such a problem in gas turbine liquid fuel systems is that most land based turbines operate most of the time on natural gas. This means that the liquid fuel system sits idle for most of the time. The liquid fuel almost always contains some water from sources such as condensation in the tank. Water also enters the fuel system from moisture rich combustion gases that can leak past check valves while the turbine is operating on natural gas. When the liquid fuel system is idle, this water separates from the fuel, collecting into a layer inside components. This forms an area of rust in the bottom of any unprotected component. This rust can prevent components from operating or can plug orifices and fuel nozzles downstream when the liquid fuel system is operated. Corrosion in the fuel system can also come from traces of acid in the fuel. This usually comes about when operating on crude or residual oils with a high sulfur content. Water washing and heating of the fuel as part of the fuel treatment process may cause a chemical reaction that produces small amounts of sulfuric acid in the fuel. Over time, this acid may cause surface pitting in fuel system components. These pits can encourage and speed the formation of fatigue cracks in highly stressed parts such as shafts or bearings. These fatigue cracks will eventually cause the failure of these parts. Two methods have been used to protect fuel system components against these corrosion problems. The first is to substitute inherently corrosion resistant materials, such as stainless steels, in place of existing materials. This is effective, but it is relatively expensive and creates lubrication and wear problems. These problems come from the poor wear characteristics of stainless steels and many other corrosion resistant materials when rubbing against other metals. Cathodic protection is the other method of protecting components against corrosion. This consists of introducing sacrificial anodes of a material, such as magnesium or zinc, that is more electrochemically active than frequently used materials such as cast iron or steel. The presence of these anodes reverses the corrosion process and makes the iron and steel parts the cathodic or protected end of the corrosion reaction. These anodes must be changed periodically since they are gradually consumed during use.
6
Asmatulu, R., and G. A. Mahmud. "Prevention of Surface Crack Formations on Polymeric Coatings Using Carbon Nanotubes." In ASME 2010 International Mechanical Engineering Congress and Exposition. ASMEDC, 2010. http://dx.doi.org/10.1115/imece2010-40256.
Анотація:
Polymeric coatings are frequently utilized for the protection of materials surface against UV light and other environmental factors (e.g., oxygen, pollutants and moistures) by many industries. However, the organic films have yet to be perfected and failures due to the degradation caused by the environmental factors are potential hazards. These hazards can cost the US economy billions of dollars and cause serious accidents. In order to minimize UV and other environmental factors on the polymeric coatings, new studies are focused on functional coating systems. In the present study, we have developed a nanocomposite coatings to reduce the crack formations and increase the life-time of the coatings. Different weight percentages (0%, 0.25%, 0.5%, 1% and 2%) of multi-wall carbon nanotubes (MWCNTs) were indvidually dispersed in the coating maetrials, and then sprayed on the surfaces of aircraft Al alloys. UV light and salt chamber tests were applied to the prepared coating samples. Optical microscopy and atomic force microscopy (AFM) studies showed that the micro and nanocrack formations on coatings were significanly lowered at higher MWCNT loadings (e.g., 2%). As a results, it is concluded that CNTs played a vital role in protecting of polymeric coatings against UV degradation and corrosion.
7
Gusarova, M. V., I. S. Malakhova, and O. V. Burmistrova. "FEATURES OF THE HUMANS’ THERMAL STATE WHEN USING A PERSONAL PROTECTIVE EQUIPMENT AGAINST POWER-FREQUENCY ELECTRIC FIELDS." In The 16th «OCCUPATION and HEALTH» Russian National Congress with International Participation (OHRNC-2021). FSBSI “IRIOH”, 2021. http://dx.doi.org/10.31089/978-5-6042929-2-1-2021-1-163-168.
Анотація:
Abstract. Introduction. When using personal protective equipment (PPE) against power-frequency electric fields (PFEF), there is a problem associated with the deterioration of the humans thermal state during a workshift when working in a hot environment. The shielding and shunting elements of the PPE increase the weight of the PPE and has an additional thermal load on a person working in a hot environment and so have a negative impact on his thermal state. The change in the indicators of the persons’ thermal state can be considered as a criteria for the impact of a complex of factors that determine the body heat exchange with the environment. Also, in addition to the impact of the PFEF and the hot environment, workers are exposed to physical exertion associated with moving around the area and lifting weights, which additionally burdens their functional state. Purpose. To study the thermal state of a person using PPE from the PFEF, when performing physical work at different thermal load levels of the environment. Materials and methods. Four practically healthy men were involved as volunteers. Before and after the experiment, the initial skin temperature indicators were recorded in 11 areas of the body surface as well as the tympanic membrane temperature and the heart rate (HR). During physical activity and rest, subjective heat and humidity sensations were also recorded every 5 minutes on the 11 areas of the body surface and the temperature of the inner surface of the clothing was determined. Before and after the experiment, the body weight of the naked volunteer and the weight of all the items included in the PPE kit were recorded. Results and discussion. During physical work at WBGT 28.0°C, ΔQts reached the permissible level (2.6 kJ/kg) after 10 minutes from the start of the work, and when working in WBGT 23.3°C – after 20 minutes, which indicated the highest rate of overheating of the human body at a higher level of the thermal load. The moisture sensitivity score at WBGT of 28.0°C by the end of the working period was 3.3. Stabilization of the HR was observed at a lower level of the thermal load, but at WBGT 28.0°C there was a HR continuous increase, which indicates a greater tension of the thermoregulation mechanisms. Conclusion. The obtained data allowed us to establish the fact of the negative impact of the use of EP-4(0) kits on the humans’ thermal state. When using the EP-4(0), it is necessary to regulate the time of continuous work in the open air: no more than 2 hours with a subsequent rest for at least 30 minutes in order to compensate heat loss as a result of using such PPE, which hinders heat and moisture exchange.
8
Chao, Nien-Hua, John A. Dispenza, and Mario E. DeAngelis. "Encapsulating Protective Layers for Enhancing Survivability of Circuit Board Assemblies in Harsh and Extreme Environments." In ASME 2012 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2012. http://dx.doi.org/10.1115/imece2012-85959.
Анотація:
Potted electronics are becoming more common in precision-guided artillery-launched munitions and also missile systems due to the requirements for miniaturization and structural-robustness. In this paper we have presented a methodology for encapsulating circuit board assemblies (CBA) with a thin polymer layer. The protective polymer layer is both flexible and soft enough to protect the CBA from damage caused by CTE mismatches, and without any appreciable degradation in the structural support during the high-g forces of projectile launch. The application process described here allows for the use of a broad range of polymer materials including those that may not be formed directly against an actual CBA. Proof-of-concept experimental tests and finite-element simulations have been performed and the tests and simulation results are shared in this paper. In addition, the protective polymer layer can also be used to improve in-circuit board crosstalk and RF interference shielding, tin-whisker growth control, moisture barrier properties, and thermal management for un-potted and potted CBAs.
Звіти організацій з теми "Protection against moisture":
1
Su, Yun, Rui Li, Guowen Song, Chunhui Xiang, and Huanjiao Dong. Numerical model of heat and moisture transfer in membrane material used for protective clothing against steam hazard. Ames: Iowa State University, Digital Repository, 2017. http://dx.doi.org/10.31274/itaa_proceedings-180814-1891.
2
Sela, Shlomo, and Michael McClelland. Investigation of a new mechanism of desiccation-stress tolerance in Salmonella. United States Department of Agriculture, January 2013. http://dx.doi.org/10.32747/2013.7598155.bard.
Анотація:
Low-moisture foods (LMF) are increasingly involved in foodborne illness. While bacteria cannot grow in LMF due to the low water content, pathogens such as Salmonella can still survive in dry foods and pose health risks to consumer. We recently found that Salmonella secretes a proteinaceous compound during desiccation, which we identified as OsmY, an osmotic stress response protein of 177 amino acids. To elucidate the role of OsmY in conferring tolerance against desiccation and other stresses in Salmonella entericaserovarTyphimurium (STm), our specific objectives were: (1) Characterize the involvement of OsmY in desiccation tolerance; (2) Perform structure-function analysis of OsmY; (3) Study OsmY expression under various growth- and environmental conditions of relevance to agriculture; (4) Examine the involvement of OsmY in response to other stresses of relevance to agriculture; and (5) Elucidate regulatory pathways involved in controlling osmY expression. We demonstrated that an osmY-mutant strain is impaired in both desiccation tolerance (DT) and in long-term persistence during cold storage (LTP). Genetic complementation and addition of a recombinantOsmY (rOsmY) restored the mutant survival back to that of the wild type (wt). To analyze the function of specific domains we have generated a recombinantOsmY (rOsmY) protein. A dose-response DT study showed that rOsmY has the highest protection at a concentration of 0.5 nM. This effect was protein- specific as a comparable amount of bovine serum albumin, an unrelated protein, had a three-time lower protection level. Further characterization of OsmY revealed that the protein has a surfactant activity and is involved in swarming motility. OsmY was shown to facilitate biofilm formation during dehydration but not during bacterial growth under optimal growth conditions. This finding suggests that expression and secretion of OsmY under stress conditions was potentially associated with facilitating biofilm production. OsmY contains two conserved BON domains. To better understand the role of the BON sites in OsmY-mediated dehydration tolerance, we have generated two additional rOsmY constructs, lacking either BON1 or BON2 sites. BON1-minus (but not BON2) protein has decreased dehydration tolerance compared to intact rOsmY, suggesting that BON1 is required for maximal OsmY-mediated activity. Addition of BON1-peptide at concentration below 0.4 µM did not affect STm survival. Interestingly, a toxic effect of BON1 peptide was observed in concentration as low as 0.4 µM. Higher concentrations resulted in complete abrogation of the rOsmY effect, supporting the notion that BON-mediated interaction is essential for rOsmY activity. We performed extensive analysis of RNA expression of STm undergoing desiccation after exponential and stationary growth, identifying all categories of genes that are differentially expressed during this process. We also performed massively in-parallel screening of all genes in which mutation caused changes in fitness during drying, identifying over 400 such genes, which are now undergoing confirmation. As expected OsmY is one of these genes. In conclusion, this is the first study to identify that OsmY protein secreted during dehydration contributes to desiccation tolerance in Salmonella by facilitating dehydration- mediated biofilm formation. Expression of OsmY also enhances swarming motility, apparently through its surfactant activity. The BON1 domain is required for full OsmY activity, demonstrating a potential intervention to reduce pathogen survival in food processing. Expression and fitness screens have begun to elucidate the processes of desiccation, with the potential to uncover additional specific targets for efforts to mitigate pathogen survival in desiccation.