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defence Technology（防务技术） 2018年第1期14卷 77-82页

作者： B.Q.Ochieze C.C.Nwobi-Okoye P.N.Atamuo lafarge Africa Plc Mfamosing Plant department of Mechanical Engineering Chukwuemeka Odumegwu Ojukwu University

Experimental study of the effect of wear parameters on the wear behaviour of A356 alloy reinforced with cow horn particles(CHp) produced by spark plasma sintering was investigated. Experiments were conducted based on the plan of experiments generated through Taguchi's(L9) technique. Tribometer was used for the wear test and Scanning electron microscope was used to analyse the worn scar of the samples. The results shows that, A356 alloy reinforced with CHp exhibited better dry sliding wear resistance than the unreinforced alloy. Wear rate decreased as the amount of CHp reinforcement increased in the matrix. It was found that, the optimum level of the factors with minimized the wear loss were obtained at: wt%CHp(20%), applied load(10 N), sliding velocity(3 m/s) and sliding distance(2000 m). It can be seen that the wear track of the sample are(D ? 0.81 and L = 42.85 mm) and(D ? 0.54 and L= 27.03 mm) for A356 alloy and composites at optimum condition respectively. The results showed that the addition of cow horn particles as reinforcing materials in A356 alloy composites increased the wear resistance of the composites greatly.

关键词： A356alloy Cow horn particles Microstructure Analysis of variance and wear behaviour

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粉煤灰混凝土抗硫酸盐侵蚀性能(英文)

硅酸盐学报 2012年第1期40卷 39-48页

作者：李观书 lafarge Research Center St Quentin Fallavier 38291France lafarge亚洲技术中心北京100027

为了探究掺粉煤灰混凝土的抗硫酸盐侵蚀性能,固定水灰比,用不同种类的粉煤灰在20℃条件下制备混凝土试样。在8℃或20℃的条件下分别水养14、28 d和90 d后,试样在20℃和8℃的条件下被置于SO24-浓度为16 g/L的硫酸钠溶液中。试样的抗硫酸... 详细信息

为了探究掺粉煤灰混凝土的抗硫酸盐侵蚀性能,固定水灰比,用不同种类的粉煤灰在20℃条件下制备混凝土试样。在8℃或20℃的条件下分别水养14、28 d和90 d后,试样在20℃和8℃的条件下被置于SO24-浓度为16 g/L的硫酸钠溶液中。试样的抗硫酸盐侵蚀性能通过目视观察和长度变化来评价。研究了粉煤灰种类、先期养护时间和温度对粉煤灰混凝土的抗硫酸盐侵蚀性能的影响。结果表明:石灰含量,硫酸盐浓度和玻璃相中的碱含量是影响粉煤灰混凝土抗硫酸盐侵蚀性能的主要因素,并且提出了粉煤灰的组成影响粉煤灰混凝土抗硫酸盐侵蚀性的机理。

关键词：粉煤灰混凝土抗硫酸盐侵蚀性粉煤灰玻璃相组成先期养护

有替代硅酸盐水泥熟料的生产的选择吗？(英文)

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硅酸盐学报 2012年第1期40卷 61-68页

作者： Ellis GARTNER lafarge Central Research St.Quentin Fallavier38291France

人们一直在寻找CO2排放量低的水硬性胶凝材料,用它替代传统的以硅酸盐水泥熟料(Portland clinker,PC)为主的水泥。介绍了几种处于不同发展时期的新型非PC基的胶凝材料体系。目前大多数水泥生产商都尽可能多地用辅助性胶凝材料替代硅酸... 详细信息

人们一直在寻找CO2排放量低的水硬性胶凝材料,用它替代传统的以硅酸盐水泥熟料(Portland clinker,PC)为主的水泥。介绍了几种处于不同发展时期的新型非PC基的胶凝材料体系。目前大多数水泥生产商都尽可能多地用辅助性胶凝材料替代硅酸盐水泥熟料。火山灰材料具有低的水硬活性,它可使用高浓度碱金属溶液来激发,得到介于"地聚合物"和石灰激发火山灰胶凝材料间的复合胶凝材料。较远期可以期待基于贝利特、硫铝酸钙和铁铝酸钙矿物组成的水泥熟料,如拉法基公司的AetherTM已投入生产。更远的将来,不产生CO2的原材料,如硅酸镁等,可能使得水泥生产中实现CO2零排放,然而,这些胶凝材料的耐久性有待验证,用其配制的混凝土中钢筋锈蚀的防护是实际应用中的关键问题。

关键词：非PC基的胶凝材料水泥生产能源消耗二氧化碳排放

Interactions between Superplasticizer and Release Agents at the Concrete/Formwork Interface

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Materials Sciences and Applications 2012年第6期3卷 384-389页

作者： Samir Bouharoun Yannick Vanhove Chafika Djelal Pascale de Caro Isabelle Dubois centre de recherche lafarge Rue du Montmurier St Quentin Fallavier France Laboratoire Génie Civil et géo-Environnement (LGCgE)—Lille Nord de France IUT de Béthune Rue de l’Université Béthune France Université de Toulouse INP LCA (Laboratoire de Chimie Agro-Industrielle) ENSIACET Allée Emile Monso Toulouse France

Improving the knowledge of rheological and tribological characteristics of fresh concrete is important to contribute to the progress of construction sites and the final quality of the work. The objective of this study is to identify the effect of a superplasticizer based on polycarboxylic ether on the tribological behavior of fresh concrete at the concrete/formwork and concrete/oil/formwork interfaces. Friction tests on fresh concrete were carried out using a plan/plan tribometer. In order to study the behavior of the superplasticizer close to the formwork, three concretes with 30% of paste and different dosage of superplasticizer were formulated. The results show that the increase of the dosage of superplasticizer reduces the friction stress. The properties of the superplasticizer generate a deflocculating action of concrete grains and lead to a stabilisation of the soap-oil micellae present in the vicinity of the formwork. Thus, the efficiency of superplasticizer depends on the quantity of fines, on the quantity of soap formed and so, on the release agent formulation.

关键词： Tribology Concrete/Formwork Interface Concrete/Oil/Formwork Interface Superplasticizer Release Agent Physicochemical

Outcomes of intracranial hemorrhage in critically ill patients with acute leukemia: Results of a retrospective cohort study

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重症医学（英文） 2024年第4期04卷 508-514页

作者： Herault Antoine Hourmant Yannick Lengliné Etienne lafarge Antoine Mariotte Eric Darmon Michael Valade Sandrine AP-HP H?pital Saint-Louis Medical ICU Paris France Université de Paris Paris France H?pital Charles Nicolle Medical ICU Rouen France AP-HP H?pital Saint Louis Hematology Department Paris France

Background::Admission to the intensive care unit (ICU) is frequently required for patients with acute leukemia (AL) because of life-threatening complications such as intracranial hemorrhage (IH). In this study, we evaluated the impact of IH on survival and neurological outcomes in this ***::This was a single-center retrospective cohort study including adult patients with AL requiring ICU admission and experiencing IH between 2002 and 2019 at Saint Louis Hospital. Leukemia type was determined according to the French-American-British classification. Brain imaging (either computed tomography or magnetic resonance imaging) was available for all the patients. The primary endpoint of the study was to describe the clinical and biological characteristics and evaluate the mortality and neurological outcome of patients hospitalized in the ICU with newly diagnosed AL and IH. The secondary endpoint was to identify predictive factors of IH in these ***::Thirty-five patients with AL were included, median age of the patients was 59.00 (interquartile range [IQR]: 36.00-66.00) years. Twenty-nine patients (82.9%) had acute myeloid leukemia, including 12 patients with acute promyelocytic leukemia. Thrombocytopenia was constant, and 48.5% of patients had disseminated intravascular coagulation (DIC). At ICU admission, the median Sequential Organ Failure Assessment score was 5 (IQR: 3-9). The median time between AL onset and IH was 2.0 (IQR: 0.0-9.5) days. The ICU and hospital mortality rates were 60.0% ( n =21) and 65.7% ( n=23), respectively. In univariate analysis, mechanical ventilation and stupor were associated with mortality, but DIC and acute promyelocytic leukemia were not. Upon multivariate analysis, stupor or coma was the only factor significantly associated with a poor outcome (odds ratio = 8.56, 95 % confidence interval: 2.40 to 30.46). Conclusion::IH is associated with a high mortality rate in AL patients, with stupor or coma at

关键词： Acute leukemia Hematological malignancies Intracranial hemorrhage Intensive care unit Critical care

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应用铝酸盐水泥的高性能干混砂浆

应用铝酸盐水泥的高性能干混砂浆

首届全国商品砂浆学术会议

作者：胡冲 Loris Amathieu 拉法基铝酸盐(中国)有限公司 lafarge Aluminates Paris

虽然铝酸盐水泥已经在欧洲和美国广泛地用在干混砂浆中,它们在中国的干混砂浆行业中仍然很少被人知晓,使用尚未普遍。在本篇文章中,作者讨论了铝酸盐水泥的主要应用。这些应用包括从简单的技术砂浆到复杂的多成分产品,诸如快速修补砂浆... 详细信息

虽然铝酸盐水泥已经在欧洲和美国广泛地用在干混砂浆中,它们在中国的干混砂浆行业中仍然很少被人知晓,使用尚未普遍。在本篇文章中,作者讨论了铝酸盐水泥的主要应用。这些应用包括从简单的技术砂浆到复杂的多成分产品,诸如快速修补砂浆、无收缩灌浆和自流平砂浆等。它们的组成都是基于铝酸盐水泥(例如拉法基铝酸盐公司的Ciment Fondu ),通常结合使用其他水硬性胶凝材料如硅酸盐水泥和硫酸钙,以及适用的有机添加剂。经验证,正是由于Ciment Eondu )的独特技术特征及其优秀的稳定性,才使得这些干混砂浆具有一系列独特的性能,它也因此成为欲获得广泛性能的砂浆产品的首选材料。

关键词：铝酸盐水泥干混砂浆工作性能力学性能耐久性

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尾砂水泥胶结充填料试验报告

中国矿山工程 1976年第Z1期 51-64+23页

作者： W.S.Weaver Luka 采矿科加拿大魁北克省芒特雷尔lafarge水泥有限公司

加拿大两个基础工业——建筑与采矿——合作发展了“水泥尾砂胶结体”,本文回顾了实验室试验的成果。加拿大水泥有限公司与两家采矿公司紧密配合下,于1961年在魁北克省的Hull开始进行研究,采用了特殊的技术以克服试验中的困难。对砂浆... 详细信息

加拿大两个基础工业——建筑与采矿——合作发展了“水泥尾砂胶结体”,本文回顾了实验室试验的成果。加拿大水泥有限公司与两家采矿公司紧密配合下,于1961年在魁北克省的Hull开始进行研究,采用了特殊的技术以克服试验中的困难。对砂浆浓度、水泥含量、尾砂粒度、白榴火山灰、掺和剂及其它变数等与水泥尾砂胶结体的影响关系均进行了研究,针对用作隔墙、铺地板、一般充填法采场的充填和深孔爆破采场的充填等都进行了研究。试验浇成6×12吋的园柱体,2×2×4呎的箱子及采用8呎长的模型采场。 1966年在安大略省的Belleville建成了更先进的大规模试验厂,1967～1970年获得国家研究委员会的津贴并进行一些特殊的试验项目,包括6吋园柱体的三向轴压力试验。对尾砂的正式研究计划现已完成。本文总结了八年来上千次试验的研究结果。

关键词：尾砂水泥矿山充填料砂浆浓度

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水泥生料磨机动态成分控制系统设计

自动化学报 1994年第4期20卷 427-435页

作者：恽源世林平上海建材学院自动化与计算机系法国Lafarge水泥公司研究所

该文对水泥工业中生料磨机的成分控制提出了一种新的动态控制方案．其主要由４部分组成：１）基于内部模型的多变量预测控制．２）在线估计原料化学成分的臼适应控制．３）基于多目标的非线性有约束最优化单元．４）对于特定批处理过程... 详细信息

该文对水泥工业中生料磨机的成分控制提出了一种新的动态控制方案．其主要由４部分组成：１）基于内部模型的多变量预测控制．２）在线估计原料化学成分的臼适应控制．３）基于多目标的非线性有约束最优化单元．４）对于特定批处理过程的给定值自调整．本方案是针对法国Ｌａｆａｒｇｅ公司某厂实际工况设计的，但同时也具有普遍意义．基于该厂实际数据的仿真试验表明本控制方案是有效的．

关键词：水泥生料磨机化学成分控制系统

THE ACCELERATED CONCRETE PRISM TEST （60℃）:VARIABILITY OF THE TEST METHOD AND PROPOSED EXPANSION LIMITS

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THE ACCELERATED CONCRETE PRISM TEST （60℃）:VARIABILITY OF ...

生料易烧性指数K1450的计算和影响因素研究与应用实践

第十二届国际混凝土碱集料反应会议

作者： Benoit Fournier Ray Chevrier Marie de Grosbois Rino Lisella Kevin Folliard Jason Ideker Medhat Shehatad Mike Thomas Steve Baxter ICON/CANMET Natural Resources Canada405 Rochester StreetOttawaONCanadaK1A 0G1 ICON/CANMET Natural Resources Canada405 Rochester StreetOttawaONCanadaK1A 0G1 lafarge North America 6150 Royalmount Av.MontrealQcCanadaH4P 2R3 lafarge North America 6150 Royalmount Av.MontrealQcCanadaH4P 2R3 department of Civil Engineering University of Texas in AustinAustinTexasUSA78712-1076 department of Civil Engineering University of Texas in AustinAustinTexasUSA78712-1076 department of Civil Engineering Ryerson University350 Victoria StreetTorontoONCanadaM5B 2K3 department of Civil Engineering University of New BrunswickFrederictonNBCanadaE3B 5A3 Steve Baxter Research Inc. 313 E.Virginia Ave.Bessemer CityNC 28016

＜正＞ This paper discusses the results of an interlaboratory study on the Accelerated Concrete Prism Test （i.e. 60℃, R.H. ＞ 95%） for ASR. Concrete mixtures were made in one laboratory with moderately- and highly-reactive Canadian aggregates. Test prisms were prepared and further tested for weight changes and expansion in the participant’s laboratories both in the standard （38℃） and the accelerated （60℃） test conditions. The results obtained in this study and in the literature indicate that the variability in the expansion results obtained in the accelerated concrete prism test is quite comparable to that of the standard CPT performed at 38℃. A review of available test results shows that a limit of 0.04% at three months generally give the same diagnostic as that obtained after one year in the standard CPT. Increased leaching of alkalis from the test prisms and an increased sulfate content in the pore solution （with consequent reduction of pH） with increasing testing temperature, likely explain why, in most cases, the main expansion phase of the test prisms at 60℃is often completed after 3 months of testing.

关键词： Alkali-silica reaction accelerated concrete prism test concrete prism test multi-laboratory variability.

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水泥 2018年第10期 7-13页

作者：郭随华任兵建姚燕 Abdellatif Boumiz 中国建筑材料科学研究总院有限公司绿色建筑材料国家重点实验室北京100024 华润水泥技术研发有限公司广东广州510460 lafarge Holcim Cement Industry Performance Lyon France

生料易烧性指数K_(1450)是一个与C_3S形成化学反应速度常数成正比的技术参数,可根据配入煤灰掺入量后的生料化学成分及1 450℃煅烧样品的f-CaO含量进行计算。K_(1450)值越高,表明生料易烧性越好;其显著性影响因素包括生料中粗颗粒石英... 详细信息

生料易烧性指数K_(1450)是一个与C_3S形成化学反应速度常数成正比的技术参数,可根据配入煤灰掺入量后的生料化学成分及1 450℃煅烧样品的f-CaO含量进行计算。K_(1450)值越高,表明生料易烧性越好;其显著性影响因素包括生料中粗颗粒石英含量、氟离子含量、熟料设计的液相量和铝率。根据K_(1450)数值高低,可以比较准确地预测水泥窑熟料煅烧热耗的相对变化;当K_(1450)从30提高至70,熟料煅烧热耗可降低10%以上。易烧性较好的生料(K_(1450)>70),由于可在更快的升温速率和更短的高温带通过时间下实现熟料烧成,且可显著减轻窑内还原气氛,因此熟料煅烧热耗较低;若通过进一步优化,使熟料中的A矿能够获得合理的晶体大小及矿物形貌,可显著提高熟料的活性。

关键词：生料易烧性指数反应动力学煅烧热耗