A new ENDF/B-VII.0-based coupled 44-neutron, 20-gamma-ray-group cross-section library was developed to investigate the latest evaluated nuclear data file (ENDF) ,in comparison to ENDF/B-VI.3 used in BUGLE-96, as well as to generate an objective-specific library. The objectives selected for this work consisted of dosimetry calculations for in-vessel and ex-vessel reactor locations, iron atom displacement calculations for reactor internals and pressure vessel, and 58Ni(n,γ) calculation that is important for gas generation in the baffle plate. The new library was generated based on the contributon and point-wise cross-section-driven (CPXSD) methodology and was applied to one of the most widely used benchmarks, the Oak Ridge National Laboratory Pool Critical Assembly benchmark problem. In addition to the new library, BUGLE-96 and an ENDF/B-VII.0-based coupled 47-neutron, 20-gamma-ray-group cross-section library was generated and used with both SNLRML and IRDF dosimetry cross sections to compute reaction rates. All reaction rates computed by the multigroup libraries are within ± 20 % of measurement data and meet the U. S. Nuclear Regulatory Commission acceptance criterion for reactor vessel neutron exposure evaluations specified in Regulatory Guide 1.190.
一种新的ENDF/B-VII。开发了基于0的耦合44中子，20伽马射线群截面库，以研究最新评估的核数据文件(ENDF)，并与ENDF/B-VI进行比较。3在BUGLE-96中使用，以及生成特定于目标的库。本工作选择的目标包括容器内和容器外反应堆位置的剂量学计算，反应堆内部和压力容器的铁原子位移计算，以及对挡板内气体生成很重要的58Ni(n，γ)计算。新的库是基于贡献和点向横截面驱动(CPXSD)方法生成的，并应用于最广泛使用的基准之一，即Oak Ridge National Laboratory Pool Critical Assembly基准问题。除了新的库，还有BUGLE-96和一架ENDF/B-VII。生成了基于0的耦合47个中子，20个伽马射线群的截面库，并将其与SNLRML和IRDF剂量学截面一起用于计算反应速率。由多组文库计算的所有反应速率与测量数据的误差在±20%以内，并符合美国核管理委员会在监管指南1.190中规定的反应堆容器中子暴露评估接受标准。
{"title":"A Broad-Group Cross-Section Library Based on ENDF/B-VII.0 for Fast Neutron Dosimetry Using the CPXSD Methodology","authors":"F. Alpan","doi":"10.1520/JAI104060","DOIUrl":"https://doi.org/10.1520/JAI104060","url":null,"abstract":"A new ENDF/B-VII.0-based coupled 44-neutron, 20-gamma-ray-group cross-section library was developed to investigate the latest evaluated nuclear data file (ENDF) ,in comparison to ENDF/B-VI.3 used in BUGLE-96, as well as to generate an objective-specific library. The objectives selected for this work consisted of dosimetry calculations for in-vessel and ex-vessel reactor locations, iron atom displacement calculations for reactor internals and pressure vessel, and 58Ni(n,γ) calculation that is important for gas generation in the baffle plate. The new library was generated based on the contributon and point-wise cross-section-driven (CPXSD) methodology and was applied to one of the most widely used benchmarks, the Oak Ridge National Laboratory Pool Critical Assembly benchmark problem. In addition to the new library, BUGLE-96 and an ENDF/B-VII.0-based coupled 47-neutron, 20-gamma-ray-group cross-section library was generated and used with both SNLRML and IRDF dosimetry cross sections to compute reaction rates. All reaction rates computed by the multigroup libraries are within ± 20 % of measurement data and meet the U. S. Nuclear Regulatory Commission acceptance criterion for reactor vessel neutron exposure evaluations specified in Regulatory Guide 1.190.","PeriodicalId":15057,"journal":{"name":"Journal of Astm International","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2012-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89647595","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Structural silicone glazed (SSG) curtain wall systems have offered architects and owners the ability to design a facade with unique aesthetic features since the 1970s. While their ability to durably withstanding natural weathering and even high wind locations across the globe has been well established, their performance under seismic events is less well recorded. This paper presents a review of the performance of SSG systems following the 8.8 magnitude earthquake that shocked Chile in Feb 2010, which registered within the top five recorded in past history. Field reviews of existing low-, medium-, and high-rise buildings were inspected in the aftermath of the event to evaluate the performance of the different SSG variations of this system type (two-sided, four-sided, stick, unitized, among other variations) combined with other facade components such as: type of glazing, glass sizes, interstory drift, width of structural grid, slab/beam rigidity, etc.
{"title":"A Review of the Behavior of Structural Silicone Glazing Systems Subjected to a Mega-Earthquake","authors":"E. Bull, Jorge Cholaky","doi":"10.1520/JAI104151","DOIUrl":"https://doi.org/10.1520/JAI104151","url":null,"abstract":"Structural silicone glazed (SSG) curtain wall systems have offered architects and owners the ability to design a facade with unique aesthetic features since the 1970s. While their ability to durably withstanding natural weathering and even high wind locations across the globe has been well established, their performance under seismic events is less well recorded. This paper presents a review of the performance of SSG systems following the 8.8 magnitude earthquake that shocked Chile in Feb 2010, which registered within the top five recorded in past history. Field reviews of existing low-, medium-, and high-rise buildings were inspected in the aftermath of the event to evaluate the performance of the different SSG variations of this system type (two-sided, four-sided, stick, unitized, among other variations) combined with other facade components such as: type of glazing, glass sizes, interstory drift, width of structural grid, slab/beam rigidity, etc.","PeriodicalId":15057,"journal":{"name":"Journal of Astm International","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2012-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83150190","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
A numerical study to compare the performance of water and copper oxide (CuO) nanofluid flowing under laminar regime in a parallel-plate channel, serving as a heat sink in an electronic device, has been presented. The geometry considered here is commonly used in the design of heat sinks suitable for cooling an array of microprocessor chips for which air cooling is insufficient. The influence of nanofluids concentration on local and average skin friction coefficients, Nusselt numbers, and convective heat-transfer coefficients in the channel have been analyzed in detail. The increases in the skin friction and heat transfer with volumetric concentration of nanoparticles have been evaluated from numerical simulations in the Reynolds number range of 100 to 2000. The analysis shows that the flow in this heat sink is hydrodynamically and thermally developing, for which the axial variations of local skin friction and local Nusselt number are presented. As an example, computational results for an 8 % volumetric concentration of CuO nanofluid shows that at a Reynolds number of 2000, the average heat-transfer coefficient increases nearly by a factor of 2 in comparison with pure water. From a detailed analysis summarized in Table 2, it is observed that there is an increase in the pressure loss as the particle concentration increases. For the CuO nanofluid of dilute concentration of 2 %, a slightly higher pumping power of about 10 % compared to water is predicted. This may be tolerable for the thermal protection of expensive electronic chips, in applications where the chip cost is the dominant factor.
{"title":"Comparison of the Performance of Copper Oxide Nanofluid with Water in Electronic Cooling","authors":"Praveen K. Namburu, K. Das, S. R. Vajjha","doi":"10.1520/JAI104342","DOIUrl":"https://doi.org/10.1520/JAI104342","url":null,"abstract":"A numerical study to compare the performance of water and copper oxide (CuO) nanofluid flowing under laminar regime in a parallel-plate channel, serving as a heat sink in an electronic device, has been presented. The geometry considered here is commonly used in the design of heat sinks suitable for cooling an array of microprocessor chips for which air cooling is insufficient. The influence of nanofluids concentration on local and average skin friction coefficients, Nusselt numbers, and convective heat-transfer coefficients in the channel have been analyzed in detail. The increases in the skin friction and heat transfer with volumetric concentration of nanoparticles have been evaluated from numerical simulations in the Reynolds number range of 100 to 2000. The analysis shows that the flow in this heat sink is hydrodynamically and thermally developing, for which the axial variations of local skin friction and local Nusselt number are presented. As an example, computational results for an 8 % volumetric concentration of CuO nanofluid shows that at a Reynolds number of 2000, the average heat-transfer coefficient increases nearly by a factor of 2 in comparison with pure water. From a detailed analysis summarized in Table 2, it is observed that there is an increase in the pressure loss as the particle concentration increases. For the CuO nanofluid of dilute concentration of 2 %, a slightly higher pumping power of about 10 % compared to water is predicted. This may be tolerable for the thermal protection of expensive electronic chips, in applications where the chip cost is the dominant factor.","PeriodicalId":15057,"journal":{"name":"Journal of Astm International","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2012-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87195492","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
D. Cobian, B. Heiderscheit, Nicole S. Daehn, P. Anderson
Background–The purpose of this investigation is to measure the normal neck and trunk motion of daily living and to compare this to annualized movements as defined by the ASTM F2423-11 and ISO 18192-1:2011 standards. Methods–Ten volunteers wore a custom sensor system that monitored their upper and lower spine motion. The system allows continuous measurement of the frequency and magnitude of spinal motion about all three axes. The angular motion can then be determined for the upper and lower spinal segments. The results were extrapolated to yield the yearly frequency and magnitudes of movements. The data were compared to ASTM and International Organization for Standardization (ISO) standards. Results–The median magnitude of neck motion was 14.3°, 13.8°, and 21.6°, and the mean annual frequency of cervical motion was 10.6 × 106, 8.5 × 106, and 5.6 × 106 movements in flexion-extension, lateral bending, and axial rotation, respectively. The observed-to-standard (ASTM) ratio of annual cervical excursion was 1.22, 1.09, and 0.69, and for ISO the ratios were 1.22, 1.09, and 1.04 in flexion-extension, lateral bending, and axial rotation, respectively. The median range of motion for the thorax relative to the iliac crest (lumbar) was 11.2°, 10.3°, and 12.5°, and the estimated number of annual movements was 6.8 × 106, 5.2 × 106, and 3.8 × 106 in flexion-extension, lateral bending, and rotation. The observed-to-standard ratios from ASTM were 0.63, 0.56 and 1.6, and for ISO they were 1.5, 1.68, and 1.59, in flexion-extension, lateral bending, and rotation respectively. Discussion–Neck and lumbar movements in healthy young adults aremore frequent that 1 × 106 times per annum. The amplitude is smaller than specified in current standards. Overall, the total annual angular excursions specified by ASTM correlated well with results, whereas the ISO specified smaller ranges of motion for the lumbar spine, and therefore the observed angular motions were greater than specified. New testing standards should consider using more physiologic movement patterns.
{"title":"Comparison of Daily Motion of the Cervical and Lumbar Spine to ASTM F2423-11 and ISO 18192-1.2011 Standard Testing","authors":"D. Cobian, B. Heiderscheit, Nicole S. Daehn, P. Anderson","doi":"10.1520/JAI103522","DOIUrl":"https://doi.org/10.1520/JAI103522","url":null,"abstract":"Background–The purpose of this investigation is to measure the normal neck and trunk motion of daily living and to compare this to annualized movements as defined by the ASTM F2423-11 and ISO 18192-1:2011 standards. Methods–Ten volunteers wore a custom sensor system that monitored their upper and lower spine motion. The system allows continuous measurement of the frequency and magnitude of spinal motion about all three axes. The angular motion can then be determined for the upper and lower spinal segments. The results were extrapolated to yield the yearly frequency and magnitudes of movements. The data were compared to ASTM and International Organization for Standardization (ISO) standards. Results–The median magnitude of neck motion was 14.3°, 13.8°, and 21.6°, and the mean annual frequency of cervical motion was 10.6 × 106, 8.5 × 106, and 5.6 × 106 movements in flexion-extension, lateral bending, and axial rotation, respectively. The observed-to-standard (ASTM) ratio of annual cervical excursion was 1.22, 1.09, and 0.69, and for ISO the ratios were 1.22, 1.09, and 1.04 in flexion-extension, lateral bending, and axial rotation, respectively. The median range of motion for the thorax relative to the iliac crest (lumbar) was 11.2°, 10.3°, and 12.5°, and the estimated number of annual movements was 6.8 × 106, 5.2 × 106, and 3.8 × 106 in flexion-extension, lateral bending, and rotation. The observed-to-standard ratios from ASTM were 0.63, 0.56 and 1.6, and for ISO they were 1.5, 1.68, and 1.59, in flexion-extension, lateral bending, and rotation respectively. Discussion–Neck and lumbar movements in healthy young adults aremore frequent that 1 × 106 times per annum. The amplitude is smaller than specified in current standards. Overall, the total annual angular excursions specified by ASTM correlated well with results, whereas the ISO specified smaller ranges of motion for the lumbar spine, and therefore the observed angular motions were greater than specified. New testing standards should consider using more physiologic movement patterns.","PeriodicalId":15057,"journal":{"name":"Journal of Astm International","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2012-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75102386","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
J. Risner, D. Wiarda, T. Miller, D. Peplow, B. Patton, M. Dunn, Benjamin Parks
The U.S. Nuclear Regulatory Commission's Regulatory Guide 1.190 states that calculational methods used to estimate reactor pressure vessel (RPV) fluence should use the latest version of the evaluated nuclear data file (ENDF). The VITAMIN-B6 fine-group library and BUGLE-96 broad-group library, which are widely used for RPV fluence calculations, were generated using ENDF/B-VI.3 data, which was the most current data when Regulatory Guide 1.190 was issued. We have developed new fine-group (VITAMIN-B7) and broad-group (BUGLE-B7) libraries based on ENDF/B-VII.0. These new libraries, which were processed using the AMPX code system, maintain the same group structures as the VITAMIN-B6 and BUGLE-96 libraries. Verification and validation of the new libraries were accomplished using diagnostic checks in AMPX, 'unit tests' for each element in VITAMIN-B7, and a diverse set of benchmark experiments including critical evaluations for fast and thermal systems, a set of experimental benchmarks that are used for SCALE regression tests, and three RPV fluence benchmarks. The benchmark evaluation results demonstrate that VITAMIN-B7 and BUGLE-B7 are appropriate for use in RPV fluence calculations and meet the calculational uncertainty criterion in Regulatory Guide 1.190. (authors)
{"title":"Development and Testing of the VITAMIN-B7/BUGLE-B7 Coupled Neutron-Gamma Multigroup Cross-Section Libraries","authors":"J. Risner, D. Wiarda, T. Miller, D. Peplow, B. Patton, M. Dunn, Benjamin Parks","doi":"10.1520/JAI104130","DOIUrl":"https://doi.org/10.1520/JAI104130","url":null,"abstract":"The U.S. Nuclear Regulatory Commission's Regulatory Guide 1.190 states that calculational methods used to estimate reactor pressure vessel (RPV) fluence should use the latest version of the evaluated nuclear data file (ENDF). The VITAMIN-B6 fine-group library and BUGLE-96 broad-group library, which are widely used for RPV fluence calculations, were generated using ENDF/B-VI.3 data, which was the most current data when Regulatory Guide 1.190 was issued. We have developed new fine-group (VITAMIN-B7) and broad-group (BUGLE-B7) libraries based on ENDF/B-VII.0. These new libraries, which were processed using the AMPX code system, maintain the same group structures as the VITAMIN-B6 and BUGLE-96 libraries. Verification and validation of the new libraries were accomplished using diagnostic checks in AMPX, 'unit tests' for each element in VITAMIN-B7, and a diverse set of benchmark experiments including critical evaluations for fast and thermal systems, a set of experimental benchmarks that are used for SCALE regression tests, and three RPV fluence benchmarks. The benchmark evaluation results demonstrate that VITAMIN-B7 and BUGLE-B7 are appropriate for use in RPV fluence calculations and meet the calculational uncertainty criterion in Regulatory Guide 1.190. (authors)","PeriodicalId":15057,"journal":{"name":"Journal of Astm International","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2012-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79824527","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Super-tall buildings of over 100 stories are coming to Korea. To prove its economic prosperity, which was developed over the last 50 years after the Korean War, Korea is willing to have super-tall buildings as a symbol of its success. Locally, structural silicone glazing has become very common to achieve aesthetically pleasing and high utilization of small land for both residential and commercial building. Because there has been no industry-wide guideline or specification for structural silicone sealants in Korea, it is worthwhile to look at the performance of locally available structural silicone sealants. In this paper, several weathering techniques were adapted from various global industry standards. Artificial weathering using filtered xenon arc radiation was applied to specimens prepared in accordance with ASTM C1135. Comparative evaluations for temperature variations and salt spraying exposure were conducted as well. Silicones in general are known to have excellent resistance to such exposure. However, since the weathering performance of a sealant can be affected by its overall composition (not just the polymer type), some silicone products showed noticeable changes in our testing when compared to their initial properties.
{"title":"Weathering Evaluation of Structural Silicone Sealants Used in Korea","authors":"Jinyoung Jung, K. Hahn, HyoungWoo Lee","doi":"10.1520/JAI104101","DOIUrl":"https://doi.org/10.1520/JAI104101","url":null,"abstract":"Super-tall buildings of over 100 stories are coming to Korea. To prove its economic prosperity, which was developed over the last 50 years after the Korean War, Korea is willing to have super-tall buildings as a symbol of its success. Locally, structural silicone glazing has become very common to achieve aesthetically pleasing and high utilization of small land for both residential and commercial building. Because there has been no industry-wide guideline or specification for structural silicone sealants in Korea, it is worthwhile to look at the performance of locally available structural silicone sealants. In this paper, several weathering techniques were adapted from various global industry standards. Artificial weathering using filtered xenon arc radiation was applied to specimens prepared in accordance with ASTM C1135. Comparative evaluations for temperature variations and salt spraying exposure were conducted as well. Silicones in general are known to have excellent resistance to such exposure. However, since the weathering performance of a sealant can be affected by its overall composition (not just the polymer type), some silicone products showed noticeable changes in our testing when compared to their initial properties.","PeriodicalId":15057,"journal":{"name":"Journal of Astm International","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2012-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80184564","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
John W Rogers, S. Viet, S. Roda, A. Fraser, W. Friedman, Joey Tianyi Zhou, D. Jacobs
The traditional method of determining dust lead loading (mass per unit area) on surfaces is to send dust wipe samples to a laboratory for analysis, and typically it takes one or more days to obtain results. Field-portable techniques taking 10 to 15 min for dust wipe lead analysis have been developed but need to be further evaluated. Dust wipe samples (n = 878) collected from a nationally representative sample of child care centers were tested by means of x-ray fluorescence (XRF) analysis with two XRF analyzer instrument models and subsequently analyzed for lead using flame atomic absorption spectrometry (FAAS). Samples were collected from floors and interior window sills and included blank and spiked quality control samples. Weighted linear regression was used to model the relationship between XRF and FAAS measurements. The correlations between FAAS and XRF measurements exceeded 0.80 (p
{"title":"Statistical Comparison of Analysis Results for Lead on Dust Wipe Samples by X-ray Fluorescence Analysis and Flame Atomic Absorption Spectrometry","authors":"John W Rogers, S. Viet, S. Roda, A. Fraser, W. Friedman, Joey Tianyi Zhou, D. Jacobs","doi":"10.1520/JAI104196","DOIUrl":"https://doi.org/10.1520/JAI104196","url":null,"abstract":"The traditional method of determining dust lead loading (mass per unit area) on surfaces is to send dust wipe samples to a laboratory for analysis, and typically it takes one or more days to obtain results. Field-portable techniques taking 10 to 15 min for dust wipe lead analysis have been developed but need to be further evaluated. Dust wipe samples (n = 878) collected from a nationally representative sample of child care centers were tested by means of x-ray fluorescence (XRF) analysis with two XRF analyzer instrument models and subsequently analyzed for lead using flame atomic absorption spectrometry (FAAS). Samples were collected from floors and interior window sills and included blank and spiked quality control samples. Weighted linear regression was used to model the relationship between XRF and FAAS measurements. The correlations between FAAS and XRF measurements exceeded 0.80 (p","PeriodicalId":15057,"journal":{"name":"Journal of Astm International","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2012-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87363621","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The biodiesel production from alkali-catalyzed transesterification of karanja oil was investigated. In this study, the effect of three parameters, i.e., reaction temperature, catalyst concentration, and molar ratio of methanol to oil on biodiesel yield was studied. Central composite design (CCD) along with response surface methodology (RSM) was used for designing experiments and estimating the quadratic response surface. Catalyst concentration was found to have a negative effect on biodiesel yield, whereas molar ratio showed positive effect. Temperature and molar ratio showed significant interaction effect. The reaction conditions were optimized for maximum response, i.e., biodiesel yield from RSM. The program for the RSM model, coupled with genetic algorithm (GA), was developed for predicting the optimized process parameters for maximum biodiesel yield to obtain a global optimal solution. The results were found to be similar from both of the methods.
{"title":"Optimization of Biodiesel Production by Response Surface Methodology and Genetic Algorithm","authors":"R. Singhal, P. Seth, D. Bangwal, S. Kaul","doi":"10.1520/JAI104328","DOIUrl":"https://doi.org/10.1520/JAI104328","url":null,"abstract":"The biodiesel production from alkali-catalyzed transesterification of karanja oil was investigated. In this study, the effect of three parameters, i.e., reaction temperature, catalyst concentration, and molar ratio of methanol to oil on biodiesel yield was studied. Central composite design (CCD) along with response surface methodology (RSM) was used for designing experiments and estimating the quadratic response surface. Catalyst concentration was found to have a negative effect on biodiesel yield, whereas molar ratio showed positive effect. Temperature and molar ratio showed significant interaction effect. The reaction conditions were optimized for maximum response, i.e., biodiesel yield from RSM. The program for the RSM model, coupled with genetic algorithm (GA), was developed for predicting the optimized process parameters for maximum biodiesel yield to obtain a global optimal solution. The results were found to be similar from both of the methods.","PeriodicalId":15057,"journal":{"name":"Journal of Astm International","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2012-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91075845","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
S. Kaul, R. Jain, S. Konathala, D. Bangwal, N. Atray, B. Kumar.
Present work is an attempt to focus on screening of microalgae chlorella minutissima, extraction of oil, and conversion of oil into biodiesel. The experimental results are supported by scanning electron microscopy/energy dispersive x-ray spectroscopy (SEM/EDX), high-performance liquid chromatography (HPLC), and gas chromatography-mass spectrometry (GC-MS) analytical techniques. The SEM/EDX results indicate microalgae contain several elements that are required for lipid metabolism, e.g., calcium, magnesium, iron, potassium, and nitrogen. HPLC analysis of hexane extracted oil shows the presence of 74.27 % of free fatty acids, 10.65 % of fatty acid esters, and 13.74 % triglycerides, besides unidentified component 1.34 %. These results are in close agreement with the high acid value of the oil. The presence of fatty acid esters in the oil were also confirmed by GC-MS analysis. Under optimized conditions, of acid catalyzed transesterification >97 % conversion of microalgae oil into FAME is observed. The studies indicate that lower reaction time is favorable for conversion to FAMEs. However, for the purpose of biodiesel feedstock, any increase in the lipid content of the algae will improve the efficiency of the process.
{"title":"Evaluation of Chlorella minutissima oil for biodiesel production.","authors":"S. Kaul, R. Jain, S. Konathala, D. Bangwal, N. Atray, B. Kumar.","doi":"10.1520/JAI104322","DOIUrl":"https://doi.org/10.1520/JAI104322","url":null,"abstract":"Present work is an attempt to focus on screening of microalgae chlorella minutissima, extraction of oil, and conversion of oil into biodiesel. The experimental results are supported by scanning electron microscopy/energy dispersive x-ray spectroscopy (SEM/EDX), high-performance liquid chromatography (HPLC), and gas chromatography-mass spectrometry (GC-MS) analytical techniques. The SEM/EDX results indicate microalgae contain several elements that are required for lipid metabolism, e.g., calcium, magnesium, iron, potassium, and nitrogen. HPLC analysis of hexane extracted oil shows the presence of 74.27 % of free fatty acids, 10.65 % of fatty acid esters, and 13.74 % triglycerides, besides unidentified component 1.34 %. These results are in close agreement with the high acid value of the oil. The presence of fatty acid esters in the oil were also confirmed by GC-MS analysis. Under optimized conditions, of acid catalyzed transesterification >97 % conversion of microalgae oil into FAME is observed. The studies indicate that lower reaction time is favorable for conversion to FAMEs. However, for the purpose of biodiesel feedstock, any increase in the lipid content of the algae will improve the efficiency of the process.","PeriodicalId":15057,"journal":{"name":"Journal of Astm International","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2012-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82430657","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Dynamic stabilization systems may be subject to anterior-posterior shear loading. However, there is no standard method established for testing a vertebrectomy model in anterior-posterior translation (as may be seen with dynamic spondylolisthesis). A new anterior-posterior shear fatigue test was devised to test one such dynamic stabilization system in anterior-posterior translation. Similar to ASTMF1717 assemblies, constructs were assembled so that screws were placed in ultra high molecular weight polyethylene blocks to attach to the test fixture. The test setup ensures that the entire shear load is transmitted by the implant system. Unlike ASTMF1717 assemblies, the blocks were rotated 180 deg from each other to facilitate loading in the test frame. This configuration is modified from an expected in vivo usage. However, the resultant load vectors are appropriately similar to the shear loads being simulated. The constructs include polymeric components and thus were tested at body temperature in a fluid bath. The blocks were moved ±5 mm with respect to each other. The constructs were cycled at 2 Hz for a minimum of 5 × 106 cycles. The constructs successfully survived 10 × 106 cycles of anterior-posterior shear displacement. Examination of the constructs demonstrated similarities between components tested via this new method and components retrieved from patients. Comparisons indicate that the shear fatigue test may stress the components as much or perhaps more than what was seen clinically.
{"title":"A Method to Test Anterior-Posterior Construct Shear Fatigue Based on the Vertebrectomy Model","authors":"L. M. Jensen, J. Dawson","doi":"10.1520/JAI103505","DOIUrl":"https://doi.org/10.1520/JAI103505","url":null,"abstract":"Dynamic stabilization systems may be subject to anterior-posterior shear loading. However, there is no standard method established for testing a vertebrectomy model in anterior-posterior translation (as may be seen with dynamic spondylolisthesis). A new anterior-posterior shear fatigue test was devised to test one such dynamic stabilization system in anterior-posterior translation. Similar to ASTMF1717 assemblies, constructs were assembled so that screws were placed in ultra high molecular weight polyethylene blocks to attach to the test fixture. The test setup ensures that the entire shear load is transmitted by the implant system. Unlike ASTMF1717 assemblies, the blocks were rotated 180 deg from each other to facilitate loading in the test frame. This configuration is modified from an expected in vivo usage. However, the resultant load vectors are appropriately similar to the shear loads being simulated. The constructs include polymeric components and thus were tested at body temperature in a fluid bath. The blocks were moved ±5 mm with respect to each other. The constructs were cycled at 2 Hz for a minimum of 5 × 106 cycles. The constructs successfully survived 10 × 106 cycles of anterior-posterior shear displacement. Examination of the constructs demonstrated similarities between components tested via this new method and components retrieved from patients. Comparisons indicate that the shear fatigue test may stress the components as much or perhaps more than what was seen clinically.","PeriodicalId":15057,"journal":{"name":"Journal of Astm International","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2012-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81764099","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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