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    <title>Transport Research International Documentation (TRID)</title>
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    <atom:link href="https://trid.trb.org/Record/RSS?s=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" rel="self" type="application/rss+xml" />
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    <copyright>Copyright © 2026. National Academy of Sciences. All rights reserved.</copyright>
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    <managingEditor>tris-trb@nas.edu (Bill McLeod)</managingEditor>
    <webMaster>tris-trb@nas.edu (Bill McLeod)</webMaster>
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      <title>Transport Research International Documentation (TRID)</title>
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      <link>https://trid.trb.org/</link>
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    <item>
      <title>Synergistic effects of dilute H₂SO₄/KMnO₄ solution soaking pretreatments on storage stability of crumb rubber modified asphalt</title>
      <link>https://trid.trb.org/View/2558745</link>
      <description><![CDATA[Waste tire crumb rubber (CR) has great potential advantages as an asphalt modifier, but its poor compatibility with base asphalt leads to insufficient storage stability of rubberized asphalt (RA). This study primarily employs a method of pretreating CR by soaking it in dilute H₂SO₄/KMnO₄ solutions. The experimental design was optimized using orthogonal testing and grey relational analysis to prepare and validate the optimal design. The study also investigates the synergistic effects of dilute H₂SO₄/KMnO₄ solutions on the CR and their impact on the storage stability of the modified asphalt. The optimal pretreatment scheme for enhancing the storage stability of crumb rubber modified asphalt (CRMA) was determined to be a pH of 1, a temperature of 80 °C, and a mass fraction of KMnO₄ of 10 %. Compared to the untreated RA, the softening point difference (SPD) and segregation index (SI) of the modified asphalt prepared using this scheme were reduced by 83.3 % and 82.2 %, respectively. Additionally, the improvement in storage stability of CRMA by the pretreatment of mixed solution of dilute H₂SO₄ and KMnO₄ was 3.1 times that of H₂SO₄ alone and 1.8 times that of KMnO4 alone. The dilute H₂SO₄ solution was more effective in removing zinc stearate from the surface of the CR compared to KMnO₄ solution. Although the mixed solution had the poorest impurity removal effect, its strong oxidizing properties led to the greatest reduction in methylene concentration, generating a large number of polar groups and resulting in the biggest specific surface area, which greatly improves the compatibility of CR and asphalt.]]></description>
      <pubDate>Fri, 20 Jun 2025 11:58:41 GMT</pubDate>
      <guid>https://trid.trb.org/View/2558745</guid>
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    <item>
      <title>Parameterization of H₂SO₄ and organic contributions to volatile PM in aircraft plumes at ground idle</title>
      <link>https://trid.trb.org/View/2402331</link>
      <description><![CDATA[Volatile Particulate Matter (vPM) emissions are challenging to measure and quantify, since they are not present in the condensed form at the engine exit plane and they evolve to first form in the aircraft plume and then continue to grow and change as they mix and dilute in the ambient atmosphere. To better understand the issues associated with the initial formation and growth of vPM, a modeling study has been undertaken to examine several key parameters that affect the formation and properties of the vPM that is created in the initial cooling and dilution of the aircraft exhaust. A modeling tool (Aerosol Dynamic Simulation Code, ADSC) that was developed and enhanced over a series of past research projects supported by NASA, DoD’s SERDP/ESTCP, and FAA was used to perform a parametric analysis of vPM. The parameters of fuel sulfur content (FSC), emitted condensable hydrocarbon (HC) concentrations, and the species profile of the HCs were used to construct a computational matrix that framed a wide range of expected parameter values. This computational matrix was executed for two representative commercial aircraft engines at ground idle and results were obtained for distances of 250 m and 1000 m downstream. From prior results, the most significant vPM emissions occur at the lowest power settings, so an engine power condition of 7% rated thrust was used. A primary goal of the parametric study is to develop an updated vPM modeling methodology and also to help interpret data collected in experimental campaigns. The parameterization proposed here allows the vPM emission composition and particle numbers to be estimated in greater detail than current methods. The aim is to provide additional understanding on how the vPM properties vary with fuel and engine parameters to increase the utility of vPM predictions.Implications: Volatile Particulate Matter (vPM) is an important contribution to the total PM emitted by aviation engines. While vPM is not currently a part of engine emissions certification regulations, vPM is used in aviation environmental impact assessments and for air quality modeling in and around airports. Current methods in use, such as FOA, were developed before many recent advances in experimental data acquisition and in understanding of vPM processes. The parameterization proposed here allows the vPM emission composition and particle numbers to be estimated in greater detail than current methods. These estimates can be used to develop inventories and provide a better estimate of total emission for most aviation engines. Its use in international regulatory tools can inform possible future regulatory actions regarding vPM.]]></description>
      <pubDate>Fri, 19 Jul 2024 13:57:58 GMT</pubDate>
      <guid>https://trid.trb.org/View/2402331</guid>
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    <item>
      <title>Laboratory investigation on the fracture toughness (Mode I) and durability properties of eco-friendly cement emulsified asphalt mortar (CRTS II) exposed to acid attack</title>
      <link>https://trid.trb.org/View/2299631</link>
      <description><![CDATA[Cement Emulsified Asphalt Mortar (CEAM) has gained prominence as a vital material for its energy and noise damping properties between the concrete roadbed and track slab in a high-speed railway system. Therefore, it is evident that CEAM properties need to be better understood and optimized. Since cracking caused by traffic loading and atmospheric conditions is one of the primary causes of failure in CEAM, addressing this issue is of great importance. Furthermore, there is a growing need for more environmentally friendly and durable CEAM due to the environmental impact of cement production in the form of greenhouse effect. The objective of this study is to assess the impact of partially replacing cement content in CEAM Type II (CRTS II) specimens with pozzolanic materials such as silica fume, metakaolin, and granite sludge to investigate how these pozzolans affect the fracture toughness (Mode I) performance under both normal (water curing) and sulfuric acid exposure conditions with the main focus on evaluating the pozzolans ability to resist acid attack from a fracture toughness perspective as the research novelty. For this purpose, specimens containing pozzolans at 5 %, 10 %, and 15 % substitution level (by weight of cement) were subjected to Semi-Circular Bending (SCB) test both under normal and exposure to 5 % sulfuric acid solution conditions. Moreover, water absorption test was conducted on specimens in normal condition as a durability index. The test results of this study revealed that substitution of these pozzolanic materials enhanced the fracture toughness in normal condition. Specifically, at a 10 % substitution as the optimal level, silica fume and metakaolin resulted in 18 % and 15 % increase in fracture toughness performance compared to the control specimen in normal condition. However, granite sludge exhibited almost the same performance as the control specimen at 5% substitution as its optimal level. In acid exposure condition, the detrimental effect of acid on the fracture toughness performance of specimens was reduced by 61 %, 55 % and 13 % for samples containing silica fume, metakaolin and granite sludge at 15% substitution level, respectively. Furthermore, water absorption test results showed that inclusion of silica fume and metakaolin at a substitution level of 15 % results in 56 % and 47 % reduction in water absorption compared to the control specimen, respectively, while for granite sludge, it was almost the same as control specimen. These results were also confirmed by SEM studies. Since the use of these pozzolans as cement substitution not only improves the fracture toughness in normal condition but also provides protection against acid-induced degradation, this study contributes to the development of a more durable and environmentally friendly CEAM.]]></description>
      <pubDate>Fri, 01 Dec 2023 09:13:19 GMT</pubDate>
      <guid>https://trid.trb.org/View/2299631</guid>
    </item>
    <item>
      <title>Effect of Acid Rain on Mechanical Properties and Aging Mechanism of Asphalt</title>
      <link>https://trid.trb.org/View/2144469</link>
      <description><![CDATA[Through the preparation of nitric acid–type acid rain, mixed acid rain, and sulfuric acid–type acid rain, an experimental method of periodic soaking of asphalt was developed. Then, using a four-component test, the four-component mass fraction of aging asphalt was obtained. The change characteristics of functional groups of aged asphalt were analyzed using infrared spectroscopy, and the aging mechanism of aged asphalt was analyzed using differential scanning calorimetry. Based on molecular dynamics theory, the bulk modulus and shear modulus of aged asphalt were calculated by establishing a molecular model of acid rain and a molecular model of aged asphalt. The diffusion coefficient, cohesive energy density, solubility, and other parameters of the aging asphalt molecular model were calculated. The influence of acid rain on the mechanical properties of asphalt was explored at the molecular level, and the mechanism of acid rain aging asphalt was explored. The results show that sulfuric acid–type acid rain has the greatest impact on the mechanical properties of asphalt and causes the most serious aging of asphalt, followed by mixed acid rain, and nitric acid–type acid rain has a relatively small impact on the mechanical properties of asphalt and the aging of asphalt.]]></description>
      <pubDate>Thu, 18 May 2023 17:08:47 GMT</pubDate>
      <guid>https://trid.trb.org/View/2144469</guid>
    </item>
    <item>
      <title>Enhanced chemical resistance to sulphuric acid attack by reinforcing Graphene Oxide in Ordinary and Portland Pozzolana cement mortars</title>
      <link>https://trid.trb.org/View/2021841</link>
      <description><![CDATA[Concrete when exposed to aggressive environmental conditions cause significant damage to the structures which substantially reduces its durability properties. The addition of nanofillers can improve hydration properties and hence improve fresh, hardened, and durability properties. In this study, two types of cements such as Ordinary Portland Cement (OPC) and Portland Pozzolana fly ash-based cement (PPC) were reinforced with Graphene Oxide (GO) to check the chemical resistance towards 5% Sulphuric acid exposure. Initial investigations such as surface characteristics and pore size measurements were analyzed through Brunauer- Emmett- Teller (BET) analysis. The resistance to Sulphuric acid attack is assessed through the change in dimensions, mass, visual observations, un-effected depth by microscopic observations, and loss in flexural strength of acid-exposed specimens. The further obtained reaction products were characterized through Field Emission Scanning Electron Microscopy (FESEM), X-ray Diffraction Analysis (XRD), Fourier Transform Infrared-ray Spectroscopy (FTIR), and Thermogravimetric Analysis (TGA) investigations. The addition of GO improved hydration and formed dense microstructure which enhanced the resistance to acid attack by measuring the change in length, cross-section, and weight loss after the acid attack. 0.04% GO addition improved 24.5% and 1.7% flexural strength after the acid attack. The formation of flower-like crystals by the addition of GO improved better resistance to acid attack confirmed through FESEM morphology. The results obtained showed GO has the potential in improving porosity characteristics by enhancing hydration characteristics. GO helped in enhancing flexural strength and improved microstructure after 28 days of acid exposure in OPC and PPC composites. The overall results showed improved resistance characteristics to Sulphuric acid attack by reinforcing optimum GO content in enhancing hydration and microstructure in OPC and PPC composites.]]></description>
      <pubDate>Fri, 30 Sep 2022 17:36:01 GMT</pubDate>
      <guid>https://trid.trb.org/View/2021841</guid>
    </item>
    <item>
      <title>Effects of different types of acid rain on water stability of asphalt pavement</title>
      <link>https://trid.trb.org/View/1905863</link>
      <description><![CDATA[As is known to all, China is one of the countries with more acid rain in the world, and acid rain is mainly distributed in the southern humid climate area of China. However, the construction of semi-flexible asphalt pavement exposed to acid rain environment is a very realistic problem. In order to clarify the influence of different types of acid rain on the water stability of semi-flexible pavement, sulfuric acid type acid rain, nitric acid type acid rain and mixed type acid rain were prepared in this paper, and the semi-flexible specimens were soaked periodically. The water stability of semi-flexible pavement under different types of acid rain corrosion was evaluated macroscopically by standard Marshall test, immersion Marshall test, freeze-thaw splitting test and vacuum saturation test. It was concluded that the Marshall stability, immersion Marshall residual stability, freeze-thaw splitting strength ratio and vacuum saturation residual stability of semi-flexible pavement under different types of acid rain showed different degrees of decline. The reasons for the decline of water stability of semi-flexible pavement under different types of acid rain corrosion were analyzed by scanning electron microscopy and infrared spectroscopy. It was concluded that the acidification condition of rainwater was the main reason for the decrease of ductility, viscosity and plasticity of petroleum asphalt, which affected the binding force between petroleum asphalt and limestone aggregate, and ultimately led to the decline of water stability of semi-flexible pavement. Based on the molecular dynamics theory, the molecular dynamics model of acid rain corrosion asphalt mixture is established. According to the sensitivity of acid components to the main components of semi-flexible asphalt mixture, the asphalt, oil, resin and calcium carbonate with the most content in semi-flexible asphalt mixture are selected to simulate and study. The changes of bonding energy and diffusion coefficient of asphalt mixture under different types of acid rain are calculated and analyzed. It is concluded that sulfuric acid acid rain has the greatest influence on the water stability of semi-flexible specimens, followed by mixed acid rain, and the influence of nitric acid rain is relatively small.]]></description>
      <pubDate>Mon, 28 Feb 2022 09:40:56 GMT</pubDate>
      <guid>https://trid.trb.org/View/1905863</guid>
    </item>
    <item>
      <title>Waveform and Frequency Spectrum Property of Ground-Penetrating Radar for Coarse-Grained Weak Sulfuric Acid Saline Soil Subgrade</title>
      <link>https://trid.trb.org/View/1746881</link>
      <description><![CDATA[To accurately obtain the waveform and spectral characteristics of saline soil subgrade, on the basis of the provincial highway widening project of Ruoqiang-Weili county in Sinkiang, the field detection of coarse-grained weak sulfuric acid saline soil subgrade was carried out by using the type LTD—2100 ground-penetrating radar (GPR) to obtain the original measured files under different water content (ω) levels. The IDSP analysis program was used to process the measured file and obtain the initial characteristics of waveform and frequency spectrum. To verify the initial characteristics, a rectangular model box was created in the laboratory with the field packing (the size was 1×0.8×0.8  m), and the water content of the model packing and temperature were manually adjusted. The model property of the waveform and frequency spectrum was obtained by detecting the model. A comparison of the initial property with the model property shows that under a positive temperature, the increase in ω will enhance the electromagnetic reflection, and when 8%<ω<27%, the reflection amplitude reaches the maximum, the maximum normalized amplitude is close to 1.0, the spectrum energy is dispersed, and the main frequency is not critical while it is lower than 200 MHz. When ω>32%, the electromagnetic loss is significantly intensified as the line mapping shows typical snowflakelike characteristics, and the point mapping shows typical linear characteristics, the spectrum energy is concentrated, the main frequency distribution range is 20–65 MHz, and the low frequency characteristics are evident. The results can provide a relevant reference for GPR detection and interpretation of coarse-grained weak sulfuric acid saline soil subgrade.]]></description>
      <pubDate>Tue, 17 Nov 2020 14:28:57 GMT</pubDate>
      <guid>https://trid.trb.org/View/1746881</guid>
    </item>
    <item>
      <title>Effects of Polymer Latex and Expansive Agent on the Resistance of Cement Asphalt Pastes to Sulfuric Acid Attacks</title>
      <link>https://trid.trb.org/View/1697795</link>
      <description><![CDATA[Two types of polymer latexes and one expansive agent were employed to investigate their effects on the resistance of cement asphalt (CA) pastes to sulfuric acid. Mercury intrusion porosimetry, a thermogravimetric analysis, and scanning electron microscopy were performed to analyze the microstructure of the CA pastes. Anticorrosion coefficients were calculated by comparing the compressive strength before and after corrosion. Results show that the chemical attack by sulfuric acid on the CA pastes begins from the neutralization reaction, accompanied by the crystalline expansion of calcium sulfate in pores and the decompositions of C-S-H gel and asphalt. At a mass ratio of asphalt to cement (A/C) of 0.2, Latex I enhances the anticorrosion coefficients of the CA pastes at low dosages but reduces them at high dosages. In contrast, Latex II results in a completely inverted effect on the anticorrosion coefficients. At an A/C of 0.6, the addition of both Latex I and II visibly increases the anticorrosion coefficients, owing to the binding effect of latex on hydrates. Compared to Latex I, Latex II results in a more obvious increase in the anticorrosion coefficients. With the inclusion of the expansive agent, the anticorrosion coefficients of the CA pastes at the A/C of 0.2 sharply decrease, while the ones at the A/C of 0.6 significantly increase. It is concluded that the precipitation of calcium sulfate crystals in a compact structure produces expansion stress and microcracks, thereby decreasing the strength and anticorrosion coefficients of CA pastes at low A/C values. In the case of high A/C values, the paste structure is difficult to be damaged, owing to the binding effects of asphalt membranes. Hence, the anticorrosion coefficients are increased by adding the expansive agent.]]></description>
      <pubDate>Thu, 23 Apr 2020 15:58:16 GMT</pubDate>
      <guid>https://trid.trb.org/View/1697795</guid>
    </item>
    <item>
      <title>Acid Resistance of Mortar Using Ferronickel Slag (FNS) Aggregate and Ground FNS as Supplementary Cementitious Material</title>
      <link>https://trid.trb.org/View/1679903</link>
      <description><![CDATA[This study evaluates the acid resistance of cement mortar using granulated ferronickel slag (FNS) as fine aggregate and fly ash or ground FNS (GFNS) as a supplementary cementitious material (SCM). The deterioration was evaluated by visual inspection, and changes of mass and strength after immersion in 1% sulfuric acid solution for up to 180 days. Acid resistance was marginally reduced when 50% volume of sand was replaced by FNS. While the control specimens suffered significant spalling and strength loss, the use of fly ash or GFNS considerably reduced the deterioration. This is attributed to the formation of a protective zone and densification of microstructure by the pozzolanic reaction, as confirmed by strength activity index, permeable voids, thermogravimetric analysis, scanning electron microscopy, and energy-dispersive X-ray spectroscopy. Overall, the specimens with FNS aggregate and GFNS or fly ash showed less deterioration than the control specimens after prolonged acid exposure.]]></description>
      <pubDate>Fri, 20 Mar 2020 16:27:51 GMT</pubDate>
      <guid>https://trid.trb.org/View/1679903</guid>
    </item>
    <item>
      <title>Experimental Analysis of Cylinder-bore Corrosive Wear by Utilizing a Radioisotope Tracer (First Report)</title>
      <link>https://trid.trb.org/View/1640577</link>
      <description><![CDATA[In order to clarify the influence of fuels containing sulfur and ethanol on cylinder-bore wear, the wear measurements by utilizing a radioisotope technique were performed. The results showed that when fuels containing sulfur were used, bore wear rate increased at a specific water temperature and depended on the base number of the engine oil. For this reason, it is estimated that the corrosive wear is caused by sulfuric acid generated from sulfur in fuels.]]></description>
      <pubDate>Tue, 22 Oct 2019 14:42:36 GMT</pubDate>
      <guid>https://trid.trb.org/View/1640577</guid>
    </item>
    <item>
      <title>Experimental Analysis of Cylinder-bore Corrosive Wear by Utilizing a Radioisotope Tracer (Second Report)</title>
      <link>https://trid.trb.org/View/1640573</link>
      <description><![CDATA[In the previous study, it had been found that bore wear increases with sulfur-containing fuels, which was assumed to be due to the corrosive wear caused by sulfuric acid generation. A hypothesis was also proposed that bore wear increases as increasing volume, acidity and reaction speed of the acid. In this study, the hypothesis was verified by investigating the influence of the bore-wall temperature on bore wear, and a wear measurement with in-cylinder injection of an acidic solution containing sulfuric acid. Furthermore, it was confirmed that those tendencies of corrosive wear does not depend on fuel injection types of engine.]]></description>
      <pubDate>Tue, 22 Oct 2019 14:42:36 GMT</pubDate>
      <guid>https://trid.trb.org/View/1640573</guid>
    </item>
    <item>
      <title>Corrosion failure analysis of a railway tanker containing concentrated sulfuric acid</title>
      <link>https://trid.trb.org/View/1584332</link>
      <description><![CDATA[In this paper, the authors carried out a corrosion failure analysis of a railway tanker containing 92.5% sulfuric acid, in order to investigate the cause of the leakage accident that occurred in 2016 and to provide a theoretical basis for preventing similar accidents. The morphology and chemical composition of the corrosion scale were characterized by SEM and EDS. The theoretical corrosion rate of the railway tanker was calculated using weight loss experiments. The corrosion behavior model was established by electrochemical experiments. In order to investigate the cause of this leakage, a mechanical model was established, and the force of the railway tanker during transportation was analyzed through ANSYS software. The results show that the tanker material (low-alloy high-tensile structural steel, Q295A) meets the quality standard, and the main cause of this leakage accident was the local corrosion failure of the tanker leading to a crack due to stress during the transportation process. The corrosion source is diluted H2SO4 solution. The main component of the corrosion scale was Fe2O3. The theoretical corrosion rate was in the range of 1.413–1.978?mm/a, and the corrosion rate increased with the decrease in the concentration of H2SO4. The corrosion type was pitting corrosion. When the brake is applied when the tanker is in full load, the stress inside the tanker is about 8.94 times higher compared to a tanker with empty load in the static state. Because of this uneven force, a crack may develop leading to leakage from the corroded area of the tanker.]]></description>
      <pubDate>Fri, 22 Feb 2019 17:06:56 GMT</pubDate>
      <guid>https://trid.trb.org/View/1584332</guid>
    </item>
    <item>
      <title>Characterization of building derived materials for partial replacement of pavement subgrade layer</title>
      <link>https://trid.trb.org/View/1565866</link>
      <description><![CDATA[This study investigates the potential of building derived materials (BDM) in its virgin state for enhancing the geotechnical and mechanical properties of soft non-swelling soil with low shear strength. A series of material and geotechnical tests carried out on soil replaced with different percentages of BDM include specific gravity, water absorption, standard Proctor’s test, permeability test, aggregate impact test (AIV), Los Angeles abrasion test, and large shear box test. The results indicated that an optimum of 18–23% of BDM by weight can be added to soil to improve its mechanical and geotechnical properties such as shear strength and compaction. This study also evaluates the compatibility of BDM in soils from sites surrounding chemical plants. For this purpose, the BDMs are exposed to sulfuric, hydrochloric, and nitric acid solutions to identify the effects of these acids on the BDM behavior. It is observed that the strength of BDM decreases after their exposure to these solutions, with maximum effect manifested by nitric acid and least by hydrochloric acid. The results of AIV and LA abrasion test on BDM exposed to chemicals show that the performance of the BDM deteriorates in the presence of chemicals. The results obtained from the proposed study can be used to promote the practical use of BDM in geotechnical applications. However, necessary precautions must be adopted for their practical application in ground improvement based on soil conditions.]]></description>
      <pubDate>Tue, 20 Nov 2018 10:21:21 GMT</pubDate>
      <guid>https://trid.trb.org/View/1565866</guid>
    </item>
    <item>
      <title>Effect of surface treatment on adhesively bonded aluminium-aluminium joints regarding aeronautical structures</title>
      <link>https://trid.trb.org/View/1530015</link>
      <description><![CDATA[The structural integrity of several structures could be determined by their joints' strength. Over the years, adhesively bonded joints have been often chosen to achieve a compromise between mass reduction and higher mechanical strength. Among others, the reduction in stress concentrations, the ability of producing smooth surfaces with no discontinuities and the reduced weight penalties are some of the factors that make this type of joint so attractive. Normally, to increase the bond strength, the materials to be bonded must be subjected to a kind of surface treatment. For metals, and more specifically, for aluminium alloys, phosphoric acid anodizing and chromic acid anodizing have been the most used treatments worldwide. However, recent investigations show that these kinds of anodizing are detrimental to health due to the release of carcinogenic substances. With this in mind, it is of the utmost importance to find alternative surface treatments that can ensure an effective bond. In this paper, a vast experimental study was performed based in the single lap joint ASTM D 1002 standard method, with the objective of determining the best alternative surface treatment (Sulfuric Acid Anodizing and Boric-Sulfuric Acid Anodizing), for aluminium-to-aluminium joints, using two types of adhesives, namely the AF 163 and the EA 9658 AERO. Results show that the optimum surface treatment is different for each type of adhesive and this fact has a huge influence on mechanical behavior of this type of aeronautical adhesive joints.]]></description>
      <pubDate>Sat, 18 Aug 2018 22:05:39 GMT</pubDate>
      <guid>https://trid.trb.org/View/1530015</guid>
    </item>
    <item>
      <title>Modeling the Condensation of Sulfuric Acid and Water on the Cylinder Liner of a Large Two-Stroke Marine Diesel Engine</title>
      <link>https://trid.trb.org/View/1503566</link>
      <description><![CDATA[Corrosive wear of cylinder liners in large two-stroke marine diesel engines that burn heavy fuel oil containing sulfur is coupled to the formation of gaseous sulfur trioxide (SO3) and subsequent combined condensation of sulfuric acid (H2SO4) and water (H2O) vapor. The present work seeks to address how fuel sulfur content, charge air humidity and liner temperature variations affects the deposition of water and sulfuric acid at low load operation. A phenomenological engine model is applied to simulate the formation of cylinder/bulk gas combustion products and dew points comply with H2O–H2SO4 vapor liquid equilibrium. By assuming homogenous cylinder gas mixtures condensation is modeled using a convective heat and mass transfer analogy combined with realistic liner temperature profiles. Condensation of water is significantly altered by the liner temperature and charge air humidity while sulfuric acid condensation (the order is a few mg per cylinder every cycle) is proportional to the fuel sulfur content. Condensation takes place primarily in the upper part of the cylinder liner where a reduction of the surface temperature or saturated charge air provides that the deposited acid can be highly diluted with water.]]></description>
      <pubDate>Wed, 25 Apr 2018 11:15:56 GMT</pubDate>
      <guid>https://trid.trb.org/View/1503566</guid>
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