Cement Wapno Beton最新文献

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Influence of vacuum infiltration on mechanical properties of polymer concrete filled with lightweight ceramic aggregates 真空浸润对轻质陶瓷骨料填充聚合物混凝土力学性能的影响
IF 0.7 4区 工程技术
Cement Wapno Beton Pub Date : 2023-06-06 DOI: 10.32047/cwb.2023.28.1.5
J. Smoleń, T. Pawlik
{"title":"Influence of vacuum infiltration on mechanical properties of polymer concrete filled with lightweight ceramic aggregates","authors":"J. Smoleń, T. Pawlik","doi":"10.32047/cwb.2023.28.1.5","DOIUrl":"https://doi.org/10.32047/cwb.2023.28.1.5","url":null,"abstract":"In this paper, the influence of vacuum infiltration of lightweight ceramic aggregates as fillers in polymeric concretes was described. In the first stage of the investigation, a set of ceramic aggregates with a high open porosity of about 27% was produced on the basis of industrial wastes. Ceramic aggregates with a size of 2 to 4 mm, hereinafter referred to as granules, were produced using contaminated glass cullet waste and coal shale. The effectiveness of granule infiltration with epoxy resin in the production of polymer concrete with high mechanical strength and relatively low mass compared to traditional concrete was discussed. The compressive strength of polymer concrete, where the aggregates were infiltrated with resin, is 87 MPa, and the polymer concrete, in which the vacuum infiltration process was not used, reaches a compressive strength of approximately 42 MPa. The resulting concrete, due to its density, is classified as a lightweight high-strength concrete.","PeriodicalId":55632,"journal":{"name":"Cement Wapno Beton","volume":"16 1","pages":""},"PeriodicalIF":0.7,"publicationDate":"2023-06-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85894693","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Experimental investigation on the application of concrete produced with limestone and dolomitic limestone aggregates in building constructions 石灰石及白云岩灰岩骨料混凝土在建筑施工中的应用试验研究
IF 0.7 4区 工程技术
Cement Wapno Beton Pub Date : 2023-06-06 DOI: 10.32047/cwb.2023.28.1.2
Adem Solak
{"title":"Experimental investigation on the application of concrete produced with limestone and dolomitic limestone aggregates in building constructions","authors":"Adem Solak","doi":"10.32047/cwb.2023.28.1.2","DOIUrl":"https://doi.org/10.32047/cwb.2023.28.1.2","url":null,"abstract":"Concrete, which is frequently used in the production process of buildings; It is made by mixing cement, water, aggregate and additives in appropriate amounts. It is important that the physical, chemical, mineralogical and especially mechanical properties of the concrete are at the desired level in terms of strength and durability of the built structures. In this direction, the selection of aggregates, which are an important part of the concrete mix, is one of the important factors affecting the concrete properties. The use of limestone and dolomitic rocks, which are rocks of sedimentary origin, in the selection of aggregates, strengthens the adhesion of aggregates with cement and improves the properties of the concrete mixture. In this study, it was aimed to identify and classify the rocks in the Western Anatolian region of Turkey and to investigate the suitability of their use as aggregates in concrete. In this context, when the physical, chemical and mineralogical properties of the rock samples taken from the field area were examined, it was understood that the rock samples were limestone and dolomitic limestone samples. In order to compare the performance of concrete mixtures prepared using limestone and dolomitic limestone aggregates, a total of 18 concrete samples were prepared, including limestone crushed aggregate, dolomitic limestone, and limestone and dolomitic limestone aggregates used together. At the end of the 7 and 28 days curing period, the concrete compressive strengths of the prepared samples with the intention of being used as concrete in building structures were tested and compared.","PeriodicalId":55632,"journal":{"name":"Cement Wapno Beton","volume":"78 1","pages":""},"PeriodicalIF":0.7,"publicationDate":"2023-06-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88406144","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Analysis of the development of autogenous shrinkage of CEM I 42.5R and CEM III/A 42.5N cement pastes with different water to cement ratios 不同水灰比CEM I 42.5R和CEM III/A 42.5N水泥浆体自收缩发展分析
IF 0.7 4区 工程技术
Cement Wapno Beton Pub Date : 2023-06-06 DOI: 10.32047/cwb.2023.28.1.4
A. Zieliński, E. Kapeluszna
{"title":"Analysis of the development of autogenous shrinkage of CEM I 42.5R and CEM III/A 42.5N cement pastes with different water to cement ratios","authors":"A. Zieliński, E. Kapeluszna","doi":"10.32047/cwb.2023.28.1.4","DOIUrl":"https://doi.org/10.32047/cwb.2023.28.1.4","url":null,"abstract":"In concrete technology, cements with a high content of Portland clinker are increasingly being replaced by blended binders with a lower carbon footprint. Such binders include blastfurnace cements, which are successfully used in concretes designed for large-scale elements, self-compacting concretes, as well as for the precast concrete industry. Blast furnace cements exhibit lower strength gain relative to Portland cements and a lower heat of hydration. Composites that incorporate them are significantly more resistant to the occurrence of thermal stresses at the early stages of curing of concrete. This paper provides a comparative study of the development of autogenous shrinkage of cement pastes made from CEM I 42.5R and CEM III/A 42.5N with a variable w/c ratio using the dilatometric method on a proprietary instrument covered by the patent PL241667. Furthermore, tests on consistency, setting times and compressive strength were performed after 2, 7 and 28 days of curing. From the analyses carried out, it was found that cement pastes containing blast furnace cement show greater autogenous shrinkage over a period of 28 days compared to pastes containing Portland cement. The pozzolanic reaction of granulated blast furnace slag contributes to the increase in recorded autogenous shrinkage. An increase in the water-cement ratio has an impact on the decreased strength gain, and the value of autogenous shrinkage. The research results indicate the need to take autogenous shrinkage into account when designing high-performance concretes containing blast furnace cement due to the increased susceptibility to shrinkage microcracks and for the durability of the material.","PeriodicalId":55632,"journal":{"name":"Cement Wapno Beton","volume":"27 1","pages":""},"PeriodicalIF":0.7,"publicationDate":"2023-06-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81351917","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Risk analysis in quality assessment of ready-mixed concrete using fuzzy logic 用模糊逻辑分析预拌混凝土质量评价中的风险
IF 0.7 4区 工程技术
Cement Wapno Beton Pub Date : 2023-06-06 DOI: 10.32047/cwb.2023.28.1.3
I. Skrzypczak, J. Zięba
{"title":"Risk analysis in quality assessment of ready-mixed concrete using fuzzy logic","authors":"I. Skrzypczak, J. Zięba","doi":"10.32047/cwb.2023.28.1.3","DOIUrl":"https://doi.org/10.32047/cwb.2023.28.1.3","url":null,"abstract":"The decision to include the considered batch of concrete in the designed class depends on the satisfaction of the conditions imposed on the strength of each individual result and the average value. The concrete conformity criteria are formulated in EN 206+A1:2016. When considering risk in concrete quality assessment, it can be assumed that there are three levels of result: low, medium, and high risk in quality assessment. Using logical operations on fuzzy sets, inference rules can be constructed to establish relationships between different variables. The paper presents an analysis of the risk of produced concrete carried out for two input parameters. Parameters on the average compressive strength of concrete and online defects obtained during compliance checks. Defects are identified by the probability of their occurrence. The third parameter introduced relates to the consequences of the occurrence of events identified with the obtained defectiveness after the compliance check of the compressive strength of the concrete produced. When verifying the compressive strength of concrete based on a sample size of n = 3, with the result obtained of a mean value of 28 MPa and a defect before and after conformity control defined at the medium defectiveness, the risk regarding the correct assessment of the quality of the produced concrete is medium.","PeriodicalId":55632,"journal":{"name":"Cement Wapno Beton","volume":"46 1","pages":""},"PeriodicalIF":0.7,"publicationDate":"2023-06-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74712644","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
The effects of apricot kernel shell nanobiochar on mechanical properties of cement composites 杏壳纳米生物炭对水泥复合材料力学性能的影响
IF 0.7 4区 工程技术
Cement Wapno Beton Pub Date : 2023-06-06 DOI: 10.32047/cwb.2023.28.1.1
M. Şi̇şman, Egemen Teomete, J. Yanık, U. Malayoğlu, Gozde Tac
{"title":"The effects of apricot kernel shell nanobiochar on mechanical properties of cement composites","authors":"M. Şi̇şman, Egemen Teomete, J. Yanık, U. Malayoğlu, Gozde Tac","doi":"10.32047/cwb.2023.28.1.1","DOIUrl":"https://doi.org/10.32047/cwb.2023.28.1.1","url":null,"abstract":"Valorization of agricultural wastes is important both economically and environmentally. This study aimed to investigate the use of biochar as a filler to improve the mechanical properties of mortar and to help sequestrate CO2. The biochar was produced by pyrolysis of apricot kernel shell at 500 °C. Nanobiochar particles with dimensions less than 500 nm were obtained by high-energy ball milling process. Scanning electron microscope was used for determining the morphology of nanobiochar. The nanobiochar at different volume percentages [0.00-0.04-0.06-0.08-0.12-0.15%] was added to mortar. The mortar was casted into 40x40x160 mm molds. After water curing at 20°C for 28 days, compressive strength and flexural strength tests were performed. The mixture containing 0.04% nanobiochar by volume had an increase in flexural and compressive strengths by 5% and 15% respectively, while its fracture energies for flexure and compression increased by 98% and 38% respectively compared to the reference mortar. Furthermore, the mixture having 0.12% volume had an increase in flexural and compressive strengths by 32% and 11%, respectively, while the increase in fracture energies for flexure and compression was 52% and 25%, respectively, compared to the reference mortar. The mechanisms of nanobiochar effect on flow, strength, and fracture energy were enlightened. The nanobiochars bridge the cracks, divert the cracks, act as hydration nucleation sites, enhance the matrix by its porous structure, and developed internal curing that led to increase in strength and fracture energy. This study suggests that the biochar produced from the apricot kernel shell has the potential to be used as a carbon sequestering mixture to improve performance of mortar and thereby utilizing waste as a construction material, contributing to the economy and environment.","PeriodicalId":55632,"journal":{"name":"Cement Wapno Beton","volume":"25 1","pages":""},"PeriodicalIF":0.7,"publicationDate":"2023-06-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75157727","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 1
An evaluation of cooling Portland cement mortars exposed to high temperature, by using firefighting foam 消防泡沫对高温下硅酸盐水泥砂浆冷却性能的评价
IF 0.7 4区 工程技术
Cement Wapno Beton Pub Date : 2023-04-19 DOI: 10.32047/cwb.2022.27.6.5
Ebru Dinler
{"title":"An evaluation of cooling Portland cement mortars exposed to high temperature, by using firefighting foam","authors":"Ebru Dinler","doi":"10.32047/cwb.2022.27.6.5","DOIUrl":"https://doi.org/10.32047/cwb.2022.27.6.5","url":null,"abstract":"The purpose of this study was to investigate the effects of cooling Portland cement mortars exposed to high temperature, with synthetic high-expansion firefighting foam. In this experimental study, mortar samples produced with Portland cement CEM I 42,5R, Rilem-Cembureau sand and tap water were first subjected to water curing for 28, 90 and 180 days and then exposed to 20°C, 150°C, 300°C, 500°C and 700°C for 3 hours, respectively. Cement mortars exposed to high temperatures were cooled with high expansion firefighting foam and the resulting flexural strength and compressive strengths were evaluated according to hydration period and temperature parameters. Subsequently, 180-day cement mortar samples exposed to high temperature were cooled using air, water, and foam cooling methods. It was determined that the air cooling method resulted in a higher compressive strength than water or foam cooling. The flexural strength, compressive strength, ultrasonic pulse velocity, and mass loss percentage values, obtained by the different cooling methods and exposure temperatures employed, were then analysed. It was determined that samples exposed to 500°C, cooling with firefighting foam, yielded a compressive strength of 9% higher, compared to water cooling. SEM images of 180-day Portland cement mortars exposed to 20°C, 300°C and 700°C and subsequently air, water and foam cooled, respectively, were obtained and analysed.","PeriodicalId":55632,"journal":{"name":"Cement Wapno Beton","volume":"11 1","pages":""},"PeriodicalIF":0.7,"publicationDate":"2023-04-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78706806","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Volumetric stability and elastic properties of concrete subjected to simulated service exposure conditions on road pavements 混凝土在道路路面模拟服务暴露条件下的体积稳定性和弹性特性
IF 0.7 4区 工程技术
Cement Wapno Beton Pub Date : 2023-04-13 DOI: 10.32047/cwb.2022.27.6.4
Karolina Bogusz, M. Glinicki
{"title":"Volumetric stability and elastic properties of concrete subjected to simulated service exposure conditions on road pavements","authors":"Karolina Bogusz, M. Glinicki","doi":"10.32047/cwb.2022.27.6.4","DOIUrl":"https://doi.org/10.32047/cwb.2022.27.6.4","url":null,"abstract":"Expressway and highway pavements are exposed to intensive impacts of exploitation, including heavy vehicle traffic and environmental factors such as temperature and moisture along with the aggression of de-icing agents. Proper selection of mineral aggregates and design of the concrete mixture composition are important for the durability of the concrete pavement. Experimental tests were conducted on concrete under simulated service exposure conditions with external exposure to a 3% sodium chloride solution. The subject of the research was the expansion and elastic properties of air-entrained concrete made with siliceous aggregates from rocks containing moderate amounts of reactive minerals. The category of reactivity of coarse aggregates was uncertain, and in the fine aggregate was moderately reactive quartz sand. Under simulated service exposure conditions on road pavements, the significant expansion of concrete specimens and a significant decrease in the resonance elastic modulus up to 12.5% were observed. The tendency of concrete to expand was related to the presence of reaction products of reactive silica in the aggregate grains with sodium and potassium hydroxides in the cement paste [ASR], confirmed by microscopic observations. Replacement of Portland cement with CEM II/A-V 42.5 N cement and CEM II/B-S 42.5 N cement significantly reduced concrete expansion and improved the stability of elastic properties. In two of the nine concrete mixtures, the selected content of siliceous fly ash and granulated blast furnace slag, 18% and 30%, respectively, turned out to be sufficient to counteract the deleterious effects of the ASR under conditions of external contact with sodium chloride solution. A practical method for predicting the durability of concrete in the conditions in which the reactivity category of the aggregate from local natural resources is uncertain was established.","PeriodicalId":55632,"journal":{"name":"Cement Wapno Beton","volume":"31 1","pages":""},"PeriodicalIF":0.7,"publicationDate":"2023-04-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86532584","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
The influence of eggshell powder and limestone on the rheological properties of cement pastes 蛋壳粉和石灰石对水泥浆体流变性能的影响
IF 0.7 4区 工程技术
Cement Wapno Beton Pub Date : 2023-04-13 DOI: 10.32047/cwb.2022.27.6.3
S. Grzeszczyk, A. Kaleta-Jurowska, K. Jurowski
{"title":"The influence of eggshell powder and limestone on the rheological properties of cement pastes","authors":"S. Grzeszczyk, A. Kaleta-Jurowska, K. Jurowski","doi":"10.32047/cwb.2022.27.6.3","DOIUrl":"https://doi.org/10.32047/cwb.2022.27.6.3","url":null,"abstract":"The paper presents the effect of the powders obtained from egg-shells and limestone on the rheological properties of cement pastes. Both powders were added to Portland cement CEM I 42.5 R, 30% by mass. The higher yield stress and plastic viscosity of the cement pastes prepared with the addition of eggshell powder, compared to the cement pastes made with limestone powder, were explained by the influence of the eggshell membrane and its chemical structure. The membrane, which absorbs water and expands in the cement paste, is causing an increase in rheological parameters. The membrane, which absorbs water and swells in the cement paste, causes an increase in viscosity and thixotropy compared to the neat cement slurry and slurry with limestone meal added as a result of particle bonding.","PeriodicalId":55632,"journal":{"name":"Cement Wapno Beton","volume":"239 1","pages":""},"PeriodicalIF":0.7,"publicationDate":"2023-04-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80424099","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Statistical analysis on mechanical behaviour of ternary blended high strength concrete 三元混合高强混凝土力学性能的统计分析
IF 0.7 4区 工程技术
Cement Wapno Beton Pub Date : 2023-04-13 DOI: 10.32047/cwb.2022.27.6.2
J. Robinson, V. Srisanthi
{"title":"Statistical analysis on mechanical behaviour of ternary blended high strength concrete","authors":"J. Robinson, V. Srisanthi","doi":"10.32047/cwb.2022.27.6.2","DOIUrl":"https://doi.org/10.32047/cwb.2022.27.6.2","url":null,"abstract":"The growing demand for high strength concrete [HSC] in the construction industry increases the usage of cement, resulting in environmental issues. Recent studies are showing that the utilization of cementitious materials in concrete can effectively reduce the volume of cement. In the present study, ternary blended combinations were prepared using cement, silica fume, and fly ash to attain the HSC. Here, cement was partially replaced by silica fume [2.5, 5, 7.5, and 10%] and fly ash [5, 10, and 15%], respectively. Mini slump cone test was conducted to identify the compatibility of cement paste with polycarboxylate ether [PCE] based superplasticizer. The packing density of aggregates was calculated to reduce the voids and improve the particle distribution in HSC. An experimental investigation was carried out, and the ultimate compressive strength was obtained as 71.55 MPa at 28 days of curing. Multi linear regression analysis was conducted to simulate the mix design for aiding the prediction of compressive strength of the HSC.","PeriodicalId":55632,"journal":{"name":"Cement Wapno Beton","volume":"80 1","pages":""},"PeriodicalIF":0.7,"publicationDate":"2023-04-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81212238","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
The risk of a different assessment of the performance of cementitious ceramic tile adhesives in the light of the results of interlaboratory comparisons 根据实验室间比较的结果,对胶凝瓷砖胶粘剂性能进行不同评估的风险
IF 0.7 4区 工程技术
Cement Wapno Beton Pub Date : 2023-03-17 DOI: 10.32047/cwb.2022.27.6.1
J. Michalak
{"title":"The risk of a different assessment of the performance of cementitious ceramic tile adhesives in the light of the results of interlaboratory comparisons","authors":"J. Michalak","doi":"10.32047/cwb.2022.27.6.1","DOIUrl":"https://doi.org/10.32047/cwb.2022.27.6.1","url":null,"abstract":"The article presents the current state of knowledge on the measurement of the adhesion of cementitious ceramic tile adhesives [CTAs] using the pull-off technique. The author discusses the results of the systematic literature review for the keywords of this article with particular attention to the interlaboratory comparisons [ILCs]. The cementitious CTAs adhesion measurements, particularly the results obtained in the ILCs, became the basis for analyzing the relationship between the participants of the conformity assessment of construction products. The analysis considers the links between science and industry and their environment resulting from formal and legal conditions related to the evaluation of construction products. Based on the study, the author proposes a mind map showing the relationships between potential participants in the CTAs compliance assessment process, with particular emphasis on ILCs. It indicates that using different criteria for evaluating the results of cementitious CTAs adhesion measurement by science and industry is not conducive to developing mutual relations between the two worlds.","PeriodicalId":55632,"journal":{"name":"Cement Wapno Beton","volume":"571 1","pages":""},"PeriodicalIF":0.7,"publicationDate":"2023-03-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76777397","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
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