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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>
    <docs>http://blogs.law.harvard.edu/tech/rss</docs>
    <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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    <item>
      <title>Evaluation of Potential Uses for a Hand Held Portable X-ray Fluorescence Spectrometer</title>
      <link>https://trid.trb.org/View/2636021</link>
      <description><![CDATA[One of the renewal projects under the Second Strategic Highway Research Program (SHRP 2) explored the potential for broad use of portable spectroscopic devices to fingerprint construction materials commonly used in transportation infrastructure. One of the instruments identified as having potential was a portable X-ray Fluorescence (XRF) instrument. In addition to the uses identified by the research project, there are some potential Iowa specific applications that are explored in this report. Testing was done on carbonate aggregates and stainless-steel reinforcement. The conclusions are: 1. The handheld XRF was quick and easy to operate compared to the laboratory XRF. A technician with a few hours of training could perform tests on a wide variety of materials such as soils, rock, paint, plastics, and metals. 2. The handheld XRF with the metals library does very well at identifying the metal type. The flexibility to add additional element limits and metal types to the library is a useful feature for use on specialty alloys. 3. Once the handheld XRF was calibrated for carbonate aggregates, it was fairly accurate and repeatable on prepared samples of rock and powder. Curved or rough surfaces appeared to reduce the accuracy and repeatability. 4. The XRF fingerprint matching algorithm was unable to consistently match pebbles from the same sample. An enhanced algorithm using the full spectrum might produce better results. Some sample preparation might also improve the accuracy.]]></description>
      <pubDate>Mon, 02 Mar 2026 16:12:39 GMT</pubDate>
      <guid>https://trid.trb.org/View/2636021</guid>
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    <item>
      <title>Research on VOCs Composition Emissions in the Oil Transport Link Based on Multi-source Detection Data</title>
      <link>https://trid.trb.org/View/2643391</link>
      <description><![CDATA[Volatile Organic Compounds (VOCs) generated in the oil transportation process are important precursors for secondary organic aerosols (SOA) and photochemical smog. These emissions have become one of the key environmental constraints in China’s 14th Five-Year Plan. Due to the diversity of oil products, VOC composition varies significantly among different types of oil, such as crude oil and refined oil, making it a critical consideration in the development of pollution control policies and treatment processes for the transportation sector. This study employs gas chromatography with a hydrogen flame ionization detector and mass spectrometry to analyze VOCs emitted from 31 types of crude oil and refined oil samples under simulated transportation and storage conditions. By utilizing multi-source detection and mass spectrometry overlay, along with area normalization spectral analysis, we provide a more accurate breakdown of VOC components from crude oil, asphalt mixtures, gasoline, diesel, aviation kerosene, and naphtha. Special attention is given to the olefin and aromatic hydrocarbon components, which contribute significantly to ozone formation. The research results can provide important basis for the research and design selection of VOCs treatment technology and equipment in the transportation process.]]></description>
      <pubDate>Tue, 20 Jan 2026 10:11:05 GMT</pubDate>
      <guid>https://trid.trb.org/View/2643391</guid>
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    <item>
      <title>Aircraft Air Quality and Bleed Air Contamination Detection: Phase 2, Volume 2 [supporting dataset]</title>
      <link>https://trid.trb.org/View/2516405</link>
      <description><![CDATA[The purpose of this project was to provide a data driven process to identify sensor technologies with the potential for detecting and identifying low levels of contaminants that may occasionally be present in aircraft engine bleed air supplies. Bleed air from a ground-based aircraft propulsion engine and an auxiliary power unit (APU) were used to supply air through an ozone/volatile organic compound (VOC) converter to the environmental control system on a Boeing 747, while injecting controlled amounts of fluid contaminants (i.e., aircraft engine oil, hydraulic fluid, and deicing fluid). Measurements of contaminants were performed at the ozone/VOC converter inlet and exit, and at the air conditioning pack exit. Ultrafine particles (UFP) were found to be a sensitive marker for engine oil contamination with measurements at all three locations showing similar, highly elevated UFP concentrations with a mean diameter near 40nm and smaller when the sample stream was cooled to near room temperature. In situ measurements showed that UFPs are generated by condensation and high UFP concentrations were not detected in uncooled bleed air. Oil contamination VOC levels were very low upstream of the ozone/VOC converter at bleed air temperatures up to 220˚C and increased at bleed temperatures of around 315˚C; however, oil contamination VOC levels remained at sub-ppmv levels. Fine particle concentrations also increased with oil contamination at lower bleed air temperatures, but not with temperatures around 315 ˚C. Secondary contaminants including pentanoic acid, heptanoic acid, acetic acid, formaldehyde, and acetaldehyde formed in the ozone/VOC converter as the oil aerosol oxidized. Consideration must be given to contaminant deposition within the bleed air system and sample lines as this deposition may lead to delayed responses and contaminant release during temperature transients. Of the sensor technologies assessed, spectrometers provided the best opportunity to detect and identify contaminants. Carbon monoxide (CO) measurements confirmed that CO is not generated in sufficient quantities to be of value as a marker for engine oil or hydraulic fluid contamination of bleed air. CO may be useful as a marker for ingestion of engine exhaust in some cases. However, carbon dioxide (CO2) is a much better marker for engine exhaust ingestion.]]></description>
      <pubDate>Fri, 07 Mar 2025 15:04:44 GMT</pubDate>
      <guid>https://trid.trb.org/View/2516405</guid>
    </item>
    <item>
      <title>Aircraft Air Quality and Bleed Air Contamination Detection; On-Wing Tests, Sensor Technologies, and Chemical Sampling (Phase 2, Volume 2)</title>
      <link>https://trid.trb.org/View/2508899</link>
      <description><![CDATA[The purpose of this project was to provide a data driven process to identify sensor technologies with the potential for detecting and identifying low levels of contaminants that may occasionally be present in aircraft engine bleed air supplies. Bleed air from a ground-based aircraft propulsion engine and an auxiliary power unit (APU) were used to supply air through an ozone/volatile organic compound (VOC) converter to the environmental control system on a Boeing 747, while injecting controlled amounts of fluid contaminants (i.e., aircraft engine oil, hydraulic fluid, and deicing fluid). Measurements of contaminants were performed at the ozone/VOC converter inlet and exit, and at the air conditioning pack exit. Ultrafine particles (UFP) were found to be a sensitive marker for engine oil contamination with measurements at all three locations showing similar, highly elevated UFP concentrations with a mean diameter near 40nm and smaller when the sample stream was cooled to near room temperature. In situ measurements showed that UFPs are generated by condensation and high UFP concentrations were not detected in uncooled bleed air. Oil contamination VOC levels were very low upstream of the ozone/VOC converter at bleed air temperatures up to 220˚C and increased at bleed temperatures of around 315˚C; however, oil contamination VOC levels remained at sub-ppmv levels. Fine particle concentrations also increased with oil contamination at lower bleed air temperatures, but not with temperatures around 315 ˚C. Secondary contaminants including pentanoic acid, heptanoic acid, acetic acid, formaldehyde, and acetaldehyde formed in the ozone/VOC converter as the oil aerosol oxidized. Consideration must be given to contaminant deposition within the bleed air system and sample lines as this deposition may lead to delayed responses and contaminant release during temperature transients. Of the sensor technologies assessed, spectrometers provided the best opportunity to detect and identify contaminants. Carbon monoxide (CO) measurements confirmed that CO is not generated in sufficient quantities to be of value as a marker for engine oil or hydraulic fluid contamination of bleed air. CO may be useful as a marker for ingestion of engine exhaust in some cases. However, carbon dioxide (CO2) is a much better marker for engine exhaust ingestion.]]></description>
      <pubDate>Mon, 24 Feb 2025 09:11:56 GMT</pubDate>
      <guid>https://trid.trb.org/View/2508899</guid>
    </item>
    <item>
      <title>A New Method for Automated Monitoring of Road Pavement Aging Conditions Based on Recurrent Neural Network</title>
      <link>https://trid.trb.org/View/2082370</link>
      <description><![CDATA[The automated monitoring of road pavement conditions is a challenging subject in intelligent transportation. However, the existing studies mostly focus on extracting pavement damages such as cracks, while the pavement aging conditions are still less investigated. In this paper, a novel method based on a modified recurrent neural network is designed for automated monitoring of asphalt pavement aging phenomena from fine-resolution satellite imagery. A spectral augmentation method is proposed to enhance the spectral details of the road pavements. A novel loss function is also proposed to improve the bi-directional gated recurrent unit (Bi-GRU) network in order to better classify different degrees of road pavement aging and non-pavement objects. In order to demonstrate the outperformance of the modified network Bi-GRU+, the Worldview-2 satellite image (16360*7728) covering 16 asphalt roads in the southwestern suburb of Beijing City is used. The results show that the proposed approach has better performance than existing machine learning methods, with an overall accuracy of 98.16% and a Kappa coefficient of 0.97. The overall processing time of the proposed method is 7836 seconds in the authors' case study. The proposed method is efficient for large-scale monitoring of road health conditions from fine-resolution satellite imagery. It can become a part of intelligent transportation and provide a new foundation for large-range automated monitoring of road pavement aging conditions.]]></description>
      <pubDate>Tue, 25 Apr 2023 09:49:41 GMT</pubDate>
      <guid>https://trid.trb.org/View/2082370</guid>
    </item>
    <item>
      <title>New analysis and evaluation method for segregation of inorganic modifier inside asphalt</title>
      <link>https://trid.trb.org/View/2064903</link>
      <description><![CDATA[In order to solve current problems of separation evaluation of inorganic modified asphalt, a new evaluating method through investigating the migration behavior of inorganic modifier was established for examining the segregation of inorganic modifier inside asphalt. Experimental process of segregation evaluation was put forward on the basis of ASTM and China MOT standards. The segregation evaluating indices and calculation method were used to analyze the segregation status of inorganic modified asphalt systematically. Furthermore, a case study was conducted on selected inorganic modifier by new evaluating method and the comparison of testing results were performed between new method and current evaluating method. Finally, the separation evaluating results were verified though using SEM and EDS analysis. The results indicated that: Compared with traditional evaluating method, this new method could be used to evaluate the actual distribution status of inorganic modifier inside asphalt and confirm the segregation level of inorganic modified asphalt. The results of SEM and EDS analysis proved and verified the rationality and correctness of this new evaluating method for inorganic modified asphalt from the micro and chemical level.]]></description>
      <pubDate>Tue, 24 Jan 2023 09:31:41 GMT</pubDate>
      <guid>https://trid.trb.org/View/2064903</guid>
    </item>
    <item>
      <title>Statistical analyses of SEM-EDS results to predict the quantity of added quicklime in a treated clayey soil</title>
      <link>https://trid.trb.org/View/2064952</link>
      <description><![CDATA[In the road construction sector, soil treatment is a method for increasing the strength and durability of fine soils that would otherwise be waste: the treatment with lime allows building embankments with clayey soils. However, in-situ and laboratory tests should be carried out to verify the correct addition of lime during earthworks. This study deals with SEM-EDS analyses in order to identify the most reliable method to prepare specimens and obtain relationship between added quicklime and Calcium content after treatment. A natural clayey soil has been tested: more than one thousand values of Calcium content have been analyzed with statistical approach. The results from one-way and two-way ANalysis Of VAriance (ANOVA) and Tukey’s test confirmed the usefulness of SEM-EDS analyses to verify quickly the quantity of added quicklime in treated soils. The most reliable method for specimen preparation consists of a sequence of procedures similar to those that occur in worksite. The high variability of Ca content in the natural soil did not allow definition of a linear reliable relationship between the added quicklime and the after-treatment Ca content. Therefore, further experimentation is on-going to define a method based on SEM-EDS analyses and valid for clays with non-uniform chemical composition.]]></description>
      <pubDate>Tue, 24 Jan 2023 09:31:41 GMT</pubDate>
      <guid>https://trid.trb.org/View/2064952</guid>
    </item>
    <item>
      <title>A Rapid In Situ Test Method for the Determination of Oxidative Field Aging Using a Handheld FTIR Spectrometer</title>
      <link>https://trid.trb.org/View/2083706</link>
      <description><![CDATA[In this study, a rapid (<45 min including analysis of results) and mildly invasive method was developed to extract a small amount of asphalt mixture (<20 gm) from an in-service road and perform the Fourier-transform infrared (FTIR) spectrometer analysis to determine its degree of oxidative aging. A handheld attenuated total reflectance (ATR) FTIR spectrometer was used as the primary equipment to investigate the carbonyl index (CI) values of six different roads in northern Louisiana. The CI value was calculated as the ratio of the peak height of the carbonyl functional group at 1,695 cm⁻¹ and the aliphatic functional group at 2,920 cm⁻¹. Three small half-inch diameter cores were made on each of the roads with a hand drill to collect the sample, while dichloromethane (DCM) was used as the quick extraction solvent. The result showed that the CI values changed from 4.79% to 10.95% for the six in-service roads, while the average CI of three different original binders from multiple sources was found to be 3.04%. It was found that the CI value of a road depends significantly on its service age, the intensity of sunlight during the daytime, and the annual average daily traffic (AADT) loading. The CI value was found higher for the roads having high service age, high AADT loading, and high ultraviolet (UV) radiation exposure. It was also found that the extracted asphalt binder on the no-loading area (which is just outside the white line) of a road encounters less aging compared to the main wheel pathway. The gradual increase in CI values with the increase in service age validates the efficacy of this method. The study will help to understand different influential factors for oxidative field aging as well as develop a rapid and reliable in situ method to investigate the aging of different service roads.]]></description>
      <pubDate>Tue, 24 Jan 2023 09:30:21 GMT</pubDate>
      <guid>https://trid.trb.org/View/2083706</guid>
    </item>
    <item>
      <title>Identification of Low Density Polyethylene, High Density Polyethylene, and Polypropylene in Asphalt Binder with a Handheld FTIR Spectrometer</title>
      <link>https://trid.trb.org/View/2083692</link>
      <description><![CDATA[Low density polyethylene (LDPE), high density polyethylene (HDPE), and polypropylene (PP) are some of the widely used plastic products around the world. As part of recycling, these plastics have been experimented to be utilized in the construction of pavements to offer an opportunity to mitigate environmental pollution. The objective of this study is to investigate if LDPE, HDPE, or PP modified asphalt binders can be identified using Fourier transform infrared (FTIR) spectroscopy. In this experiment, 3% and 9% of each of the three unused plastics flakes were added to asphalt binders using a high shear mixer. Additionally, two more grades of PP were used—industrial waste (IWPP) and solid waste (SWPP). The FTIR analysis was performed using the peak height method after performing a two-point method for index calculation. For LDPE and HDPE, the results indicate that these plastic-modified asphalt binders neither show any new peak nor show significant intensity difference in existing peaks in the spectra and hence cannot be identified. However, IWPP modified asphalt binder shows a new peak at 1,014 cm⁻¹ which is not present in any of the unmodified neat binders. Moreover, SWPP modified asphalt binder as well as pure PP modified asphalt binder show the presence of a new peak between 997 and 1,000 cm⁻¹. The height of the absorbance peak also increases with the change in PP percentage from 0% to 9% (R² = 0.891 for pure PP, R² = 0.950 for SWPP, and R² = 0.747 for IWPP). It is likely that the peak at 1,014 cm⁻¹ indicates the presence of siloxane, Si–O–Si stretching vibration, while the peak at 997 cm⁻¹indicates the isotactic polypropylene band functional group. The result of this study would help identify the presence of polypropylene in any asphalt binder with a handheld FTIR in a rapid, portable, and non-destructive technique.]]></description>
      <pubDate>Tue, 24 Jan 2023 09:30:20 GMT</pubDate>
      <guid>https://trid.trb.org/View/2083692</guid>
    </item>
    <item>
      <title>Utilization of XRF for ASR</title>
      <link>https://trid.trb.org/View/2085719</link>
      <description><![CDATA[This research will investigate the applicability of wavelength dispersive XRF and handheld versions for use in conduct of chemical ASR test.]]></description>
      <pubDate>Fri, 16 Dec 2022 14:15:15 GMT</pubDate>
      <guid>https://trid.trb.org/View/2085719</guid>
    </item>
    <item>
      <title>Interferometric Techniques for Crank-Angle Resolved Measurements of Gas Spectra in Engines</title>
      <link>https://trid.trb.org/View/1817925</link>
      <description><![CDATA[The authors discuss combustion gas spectra measured by interference spectrometers and their relevance for engine studies. First, they discuss infrared H₂O thermal emission spectra from in-cylinder piston engine gases with a novel operation mode of a standard FTIR. Second, they discuss ultraviolet OH absorption spectra in an atmospheric-pressure flame using a spatial heterodyne spectrometer (SHS) suitable for single-shot measurements of spectra from engines. The authors emphasize the unique ability of interference spectrometers to gather high-resolution spectra at high throughput and the associated value to the engine researcher.]]></description>
      <pubDate>Mon, 24 Oct 2022 10:22:53 GMT</pubDate>
      <guid>https://trid.trb.org/View/1817925</guid>
    </item>
    <item>
      <title>A Novel Spectroradiometeric Methodology for the Validation of Source Approval of Hot Mix Asphalt Surface Mix Aggregate</title>
      <link>https://trid.trb.org/View/1909502</link>
      <description><![CDATA[The quality assurance and quality control (QA/QC) procedures routinely used for the validation of source approval of HMA surface mix aggregates are laborious, time-consuming, and expensive. Subsequently, the Maryland State Highway Administration (SHA) in order to enhance her operational process seeks to employ a faster, real-time, accurate and cost effective procedure for the validation of pre-approved aggregates. This paper presents a summary of the development of the novel spectroradiometeric methodology. The spectra of 42 aggregate samples from 19 different quarries were extracted using the FieldSpec 4 spectroradiometer (FS4), and the spectral data were analyzed using Chemometrics methodology. The result obtained from the methodology appears encouraging. The Chemometrics was able to discriminate limestone base on the quarry locations. It was also able to correctly determine (classified 100%) the source of aggregates samples in terms of not belonging to a given aggregate sample population. To a limited extent, this methodology was able to explain some of the aggregates’ frictional and physical variability within a given quarry over a period of time, thus making it a useful diagnostic tool. It is hoped that these methodologies will enhance the SHA’s operational process by reducing the time and cost of evaluating HMA surface mix. The system to be developed will utilize the spectrometric technology in providing a real time evaluation of aggregates during production.]]></description>
      <pubDate>Fri, 16 Sep 2022 14:05:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/1909502</guid>
    </item>
    <item>
      <title>Enhancing the ABS ACOUSTIC BUBBLE SPECTROMETER® for Kansas </title>
      <link>https://trid.trb.org/View/2015224</link>
      <description><![CDATA[Degradation of in-service concrete infrastructure has proven to be a large public expense, estimated in the billions of dollars annually in the US. Degradation of bridge decks and concrete pavement joints forces agencies like KDOT to direct funds toward repair, rehabilitation, and / or replacement activities at the expense of other important programs and initiatives. Thus, avoiding degradation is an important goal. Freeze-thaw (F-T) degradation of concrete pavements represents a significant and expensive problem for Midwest states, including Kansas. Determining the susceptibility of a particular concrete mix to F-T degradation is a complicated problem, however a handful of mix-design related parameters including aggregate type and content, water-to-cementitious materials ratio, supplementary cementitious materials, and entrained air content have all been shown to influence F-T durability. Well-distributed entrained air in the Portland cement paste provides room to relieve water pressure by changing volume and also reduces the concrete stiffness, both of which reduce concrete tensile stresses during freezing. T.C. Powers recognized the importance of entrained air for combatting F-T durability as early as 1955 and little has changed to alter this theory in the past 65 years; entrained air remains a key F-T durability requirement. Current testing protocols for measuring total air content (e.g. ASTM C231) are reliable, but are not capable of assessing the air void system quality. With the support of the US Department of Transportation and the technical monitoring of the Federal Highway Administration, DYNAFLOW, INC. has adapted the ABS ACOUSTIC BUBBLE SPECTROMETER® for the task of assessing air void system quality in fresh concrete. Using acoustic transducers submerged in the fresh concrete, the ABS technology provides information on the quantity and size range of detected bubbles as well as some quantities of interest from the well-known ASTM C457 test in less than one minute, including sample collection. Currently the robustness of the ABS for arbitrary concrete mixtures has not been established yet, nor is the predictive capability for assessing freeze-thaw protection. The ABS should be independently tested to assess its readiness for field implementation and to provide input to DYNAFLOW, INC. for its improvement. In a separate project, the ABS ACOUSTIC BUBBLE SPECTROMETER® will be evaluated for the ability to predict freezing and thawing performance of concrete mixtures prepared in the laboratory with carefully parameterized mixture design characteristics. The ABS ACOUSTIC BUBBLE SPECTROMETER® should also be evaluated for field prepared mixtures.]]></description>
      <pubDate>Tue, 30 Aug 2022 17:20:10 GMT</pubDate>
      <guid>https://trid.trb.org/View/2015224</guid>
    </item>
    <item>
      <title>Continuous Emission Monitoring System Project</title>
      <link>https://trid.trb.org/View/1948596</link>
      <description><![CDATA[Marine vessels contribute a significant portion of total pollutant gas and particulate matter emissions near ports and waterways across the United States. As such, current International Convention for the Prevention of Pollution from Ships (MARPOL), US Federal, and California Air Resources Board emissions regulations dictate engine exhaust emission limits on CO, NOx, Total Hydrocarbons (THC), and Particulate Matter (PM). The Marine Engine Testing and Emissions Laboratory (METEL) at Maine Maritime Academy (MMA) was created to assist and address the emission reduction needs of the marine industry due to regulatory requirements. This report outlines the development of a Continuous Emissions Monitoring System (CEMS) to quantify all gas and particulate emission from laboratory testing and on board vessel testing at sea. A Fourier Transform Infrared (FTIR) spectrometer was selected to measure gaseous emissions while a Scanning Electrical Mobility Spectrometer (SEMS) was employed to measure exhaust particulate matter emissions. This report outlines the instrumentation and testing procedures developed to create the continuous emissions monitoring system at the Marine Engine Testing and Emissions Laboratory at Maine Maritime Academy. Outstanding issues and suggested improvements are also outlined to aid the development of future CEMS.]]></description>
      <pubDate>Thu, 12 May 2022 17:12:36 GMT</pubDate>
      <guid>https://trid.trb.org/View/1948596</guid>
    </item>
    <item>
      <title>Temperature dependency of VOCs release characteristics of asphalt materials under varying test conditions</title>
      <link>https://trid.trb.org/View/1933997</link>
      <description><![CDATA[Asphalt pavement is increasingly used in paving and roofing. However, the release of volatile organic compounds (VOCs) from asphalt harm both the environment and humans. Various methods were applied to characterize the VOCs for better understanding and inhibiting. However, asphalt VOCs have huge heating temperature dependency, which makes the asphalt VOCs’ characterization complicated. In this research, three kinds of heating conditions, thermal gravimetric (TG) analyzer, pyrolysis (PY) analyzer, and thermal desorber (TD), were compared to determine the temperature dependency of VOC release characteristics. Gas chromatography and mass spectrometer (GC-MS) were then coupled for VOC detection. Results indicated that the TG heating condition can surely simulate the volatilization of VOCs from some asphalt that is not in contact with air (no oxygen) during the actual construction process, while PY and TD represent the substances released by the asphalt due to the boiling point at a certain temperature and under the actual construction process, respectively. The components detected by TG heating condition are both large and small molecules, while PY and TD heating condition will detect large molecules or small molecules, respectively. The VOC composition results under various heating conditions reflect the chemical reaction law of asphalt molecules in the heating process. When heating asphalt binders to a higher temperature, macromolecular substances will gradually crack and oxidize into small molecular substances, sulfides and nitrides. With the increase of temperature, the change trend of VOC components under different conditions is different.]]></description>
      <pubDate>Mon, 25 Apr 2022 10:06:46 GMT</pubDate>
      <guid>https://trid.trb.org/View/1933997</guid>
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