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Characterization in Greenhouse Conditions of Two Salt Tolerant Citrumelo （Citrus paradisi Macf. x Poncirus trifoliata （L.） Raf.） Cultivars

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Journal of Life Sciences 2014年第12期8卷 955-966页

作者： Anas Fadli Ouiam Chetto abdelhak Talha Rachid Benkirane Raphael Morillon Hamid Benyahia Department of Plant Breeding and Germplasm Conservation National Institute for Agricultural Research (INRA) Kenitra 14000Morocco Department of Biology Faculty of Science lbn Tofail University Kenitra 242 Morocco Department of Genetic Improvement and Adaptation of Mediterranean and Tropical Plants Agricultural Research Center forInternational Development (CIRAD) Montpellier 34398 Cedex 5 France

Increasing salinity in Mediterranean soils and the wide spread of citrus tristeza virus have challenged the use of sour orange （Citrus aurantium） and have accelerated the process of seeking alternative rootstocks. In the present study, nine cultivars of citrumelo （Citrus paradisi Macf. x Poncirus trifoliata （L.） Raf.） were evaluated for salt tolerance. Two month-old seedlings were raised under greenhouse conditions and irrigated with a half strength Hoagland solution supplemented with different concentrations of NaCI, i.e., 0 mM, 35 mM and 85 mM. Tolerance was assessed after two months of stress by measuring stem growth, number of leaves, fresh and dry weight organs and leaf water, chlorophyll and chloride contents. A differential behavior was noticed among the seedlings we studied. When using increased concentration of salt in irrigation water, all the parameters were significantly reduced except for leaf chloride content which highly increased in response to stress. At 85 mM, the cultivar SC2 showed a high tolerance resulting in less apparent leaf symptoms, higher growth and higher leaf chlorophyll content when compared to other seedlings. Similarly, the cultivar C4475-C was shown to be a strong root chloride excluder with less than 2.6% DW （dry weight） chloride accumulation at leaf level. By contrast, our results suggest that C4475-A and C4475-B are salt sensitive cultivars regarding to all the parameters studied while the other citrumelos were considered as moderately tolerant.

关键词： Citrus rootstock salinity growth NaCI chloride screening

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Elaboration and Characterization of Mullite Refractory Products from Moroccan Andalusite

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New Journal of Glass and Ceramics 2012年第3期2卷 121-125页

作者： Mostafa Sardy abdelhak Arib Kacem El Abbassi Redouane Moussa Moussa Gomina EMPM-LPCMI Faculty of Science of Ain ChockCasablancaMorocco Centre for Study and Research of Mineral Phosphates CasablancaMorocco CRISMAT UMR 6508 ENSICAEN/CNRSCaenFrance

Enrichment of schist mined in Morocco resulted in an extract essentially made of andalusite, quartz and muscovite, which was investigated with the aim to synthesize mullite refractory materials. X-ray diffraction analysis was used to assess phase transformations upon heating at different temperatures. Mullite formation starts as early as 1200℃ and seems almost total at 1450℃. This process correlates with a weak shrinkage (3.5% at 1450℃) and the formation of an important glass phase. Green compacts obtained by unidirectional pressing the extract powder were heated under air in the temperature range 1200℃ - 1600℃. Chemical and mechanical properties of these materials were investigated and correlated with their microstructure.

关键词： Andalusite Mullite Refractory Structure Mechanical Properties

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Perovskite Formation and Dielectric Responses in PZN Modified PMF-PZT Ceramics

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Journal of Chemistry and Chemical Engineering 2014年第3期8卷 250-253页

作者： Karima Bounab Zelikha Necira Hayet Menasra Sofiane Ameid abdelhak Maklid Ahmed Boutarfaia Laboratory of Applied Chemistry Department of Science Matter University ofBiskra Biskra 07241 Algeria Laboratory of Semiconductor and Metal Department of Science Matter University of Biskra Biskra 07241 Algeria

PMF-PZN-PZT （0.01Pb（Mol/3Fe2/3）O3-xPb（Znl/3Nb2/3）O3-（O.99-x）P（Zro53Tio 47）03 piezoelectric ceramics）, where x = 0.00 0.01, 0.03, 0.05 and 0.07 were prepared by a conventional mixed-oxide method. The results show that the pure peroveskit phase forms in these ceramics. X-ray diffraction analysis indicated that the phase of the material is a MPB （morphotropic phase boundary） structure. The effects of PZN content on the crystal structure and electrical properties were investigated, optimal dielectric properties were achieved at composition x = 0.07 ceramics by calcination at 800 ℃ and sintering at 1,180 ℃, with a curie temperature of approximately 430 ℃. These results clearly show the significance of PZN in controlling the electrical responses of the PMF-PZN-PZT system.

关键词： Perovskit dielectric properties MPB Curie temperature.

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Variable change in renal function by hypertonic saline

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World Journal of Critical Care Medicine 2014年第2期3卷 61-67页

作者： Jesse J Corry Panayiotis Varelas Tamer abdelhak Stacey Morris Marlisa Hawley Allison Hawkins Michelle Jankowski Department of Neurology Henry Ford Hospital Department of Neurosurgery Henry Ford Hospital Department of Biostatistics Henry Ford Hospital

AIM: To investigate the effects of hypertonic saline in the neurocritical care ***: We retrospectively reviewed our hospital's use of hypertonic saline(HS) since March of 2005, and prospectively since October 2010. Comparisons were made between admission diagnoses, creatinine change(Cr), and HS formulation(3% Na Cl, 3% Na Cl/sodium acetate mix, and 23.4% Na Cl) to patients receiving normal saline or lactated ringers. The patients(n = 1329) of the retrospective portion were identified. The data presented represents the first 230 patients with data. RESULTS: Significant differences in Acute Physiology and Chronic Health Evaluation Ⅱ scores and GlasgowComa Scale scores occurred between different saline formulations. No significant correlation of Cl- or Na+ with Cr, nor with saline types, occurred. When dichotomized by diagnosis, significant correlations appear. Traumatic brain injury(TBI) patients demonstrated moderate correlation between Na+ and Cr of 0.45. Stroke patients demonstrated weak correlations between Na+ and Cr, and Cl- and Cr(0.19 for both). Patients receiving HS and not diagnosed with intracerebral hemorrhage, stroke, subarachnoid hemorrhage, or TBI demonstrated a weak but significant correlation between Cl- and Cr at ***: Cr directly correlates with Na+ or Cl- in stroke, Na+ in TBI, and Cl- in other populations. Prospective comparison of HS and renal function is needed.

关键词： Hypertonic saline solution Sodium chloride Acute kidney injury Cerebral edema Critical care

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Burden of celiac disease in the Mediterranean area

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World Journal of Gastroenterology 2011年第45期17卷 4971-4978页

作者： Luigi Greco Laura Timpone abdelhak Abkari Mona Abu-Zekry Thomas Attard Faouzi Bouguerrà Paskal Cullufi Aydan Kansu Dusanka Micetic-Turk Zrinjka Miak Eleftheria Roma Raanan Shamir Selma Terzic European Laboratory for Food Induced Diseases Federico Ⅱ University of Naples Hopital des Enfant Ibn Rochd de Casablanca Children's Hospital Gastrointestinal Unit Cairo University University of Malta Medical School Hopital des Enfants de Tunis Department of Gastroenterology and Hepatology University Hospital Center "Mother Teresa" Department of Pediatric Gastroenterology Ankara University Dikimevi/Mamak University Medical Centre Paediatric Department Children's Hospital Zagreb Athens University Aghia Sophia Children's Hospital Schneider Children's Medical Center of Israel Tel-Aviv University University Clinical Center Tuzla Children's Hospital

AIM: To estimate the burden of undiagnosed celiac disease (CD) in the Mediterranean area in terms of morbidity, mortality and health cost. METHODS: For statistics regarding the population of each country in the Mediterranean area, we accessed authoritative international sources (World Bank, World Health Organization and United Nations). The prevalence of CD was obtained for most countries from published reports. An overall prevalence rate of 1% cases/total population was finally estimated to represent the frequency of the disease in the area, since none of the available conf idence intervals of the reported rates significantly excluded this rate. The distribution of symptoms and complications was obtained from reliable reports in the same cohort. A standardized mortality rate of 1.8 was obtained from recent reports. Crude health cost was estimated for the years between symptoms and diagnosis for adults and children, and was standardized for purchasing power parity to account for the different economic prof iles amongst Mediterranean countries. RESULTS: In the next 10 years, the Mediterranean area will have about half a billion inhabitants, of which 120 million will be children. The projected number of CD diagnoses in 2020 is 5 million cases (1 million celiac children), with a relative increase of 11% compared to 2010. Based on the 2010 rate, there will be about 550 000 symptomatic adults and about 240 000 sick children: 85% of the symptomatic patients will suffer from gastrointestinal complaints, 40% are likely to have anemia, 30% will likely have osteopenia, 20% of children will have short stature, and 10% will have abnormal liver enzymes. The estimated standardized medical costs for symptomatic celiac patients during the delay between symptom onset and diagnosis (mean 6 years for adults, 2 years for children) will be about €4 billion (€387 million for children) over the next 10 years. A delay in diagnosis is expected to increase mortality: about 600 000 celiac pat

关键词： Pediatric Celiac disease Short stature Anemia Osteopenia Purchasing power parity Standardized mortality rate Mediterranean area

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基于夹杂-细晶粒区-鱼眼疲劳失效的超长寿命预测模型

基于夹杂-细晶粒区-鱼眼疲劳失效的超长寿命预测模型

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第三届中国超高周疲劳学术会议

作者：邓海龙李伟孙振铎 Nehila abdelhak 刘鹏飞北京理工大学机械与车辆学院

当前在航天、航空及车辆等领域中,机械部件的实际承载周期已远超10,甚至达到10-10。同时,发生在这个超长寿命区(>10 cycles)的疲劳失效现象,屡见不鲜。因此,明确合金钢超长寿命疲劳失效机理,提出合适的超长寿命预测方法已成为当前疲劳... 详细信息

当前在航天、航空及车辆等领域中,机械部件的实际承载周期已远超10,甚至达到10-10。同时,发生在这个超长寿命区(>10 cycles)的疲劳失效现象,屡见不鲜。因此,明确合金钢超长寿命疲劳失效机理,提出合适的超长寿命预测方法已成为当前疲劳研究领域的一个热点。本文旨在研究夹杂-细晶粒区-鱼眼诱发疲劳失效的超长寿命预测模型。然而,现有的超长寿命预测模型或方法多以裂纹扩展为基础,未虑及细晶粒区(fine granular area,FGA)、裂纹长度及裂纹萌生等对由内部夹杂诱发疲劳失效的影响。众所周知,疲劳过程是由裂纹萌生和裂纹扩展两方面组成。尤其在低应力-长寿命区,裂纹的萌生应占据一定的比重.因此,同时虑及裂纹萌生及扩展的影响,进而建立全寿命预测方法,亟待研究。在本研究中,基于Cr-Ni-W合金钢超长寿命疲劳试验结果及夹杂-细晶粒区-鱼眼诱发失效的疲劳特征,结合局部应力-寿命法和位错-能量法,分别构建了局部裂纹萌生寿命模型(local crack initiation life,LCIL)和考虑夹杂及细晶粒区影响的裂纹萌生寿命模型(inclusion and FGA based crack initiation life,IFCIL),并与传统Tanaka-Mura裂纹萌生寿命模型(T-M)进行了对比分析。其次,考虑裂纹从小到长的扩展特征,将细晶粒区作为小裂纹与长裂纹扩展行为的转换点,提出了小裂纹+长裂纹扩展模型,最终形成了包含裂纹萌生和扩展在内的全寿命预测模型。比较之下,IFCIL模型有较好的预测精度。在同一裂纹长度下,高应力区的裂纹萌生较快,而在低应力区的裂纹萌生较慢。在高应力区,同一应力幅值下的疲劳寿命随着裂纹长度的减小而明显减少。但在低应力区,这一趋势并不明显。当裂纹长度近似为细晶粒区半径时,其裂纹萌生寿命几乎等同于全寿命。随着应力幅值的降低,裂纹扩展寿命在全寿命中的比重会越来越低,即使在整体上,裂纹扩展寿命占全寿命的比重也较小。全寿命预测精度在±2倍偏差以内,可有效预测夹杂-细晶粒区-鱼眼诱发疲劳失效的超长寿命。

关键词：超长寿命疲劳夹杂起裂细晶粒区鱼眼寿命预测

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渗碳CrMn齿轮钢超高周疲劳行为及强度预测模型研究

渗碳CrMn齿轮钢超高周疲劳行为及强度预测模型研究

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第三届中国超高周疲劳学术会议

作者：孙振铎李伟邓海龙 Nehila abdelhak 刘鹏飞北京理工大学机械与车辆学院

在机械工业中,为了提高工程设备和机械结构中的齿轮、轴等传动关键零部件的耐磨、抗腐蚀及抗疲劳性能,常对其采取渗碳等表面强化处理。近年来,由于轴、齿轮等关键零部件的超长服役寿命需求越来越高,这使得表面强化钢在超高周区(10-10)... 详细信息

在机械工业中,为了提高工程设备和机械结构中的齿轮、轴等传动关键零部件的耐磨、抗腐蚀及抗疲劳性能,常对其采取渗碳等表面强化处理。近年来,由于轴、齿轮等关键零部件的超长服役寿命需求越来越高,这使得表面强化钢在超高周区(10-10)的疲劳行为受到了极大的关注。最近研究表明,表面强化钢或高强度钢在超高周区的疲劳失效主要诱发于内部的非金属夹杂。从而,夹杂的大小、分布等特性与材料的超高周疲劳强度之间建立了密切的联系。基于夹杂与小裂纹的等效关系,Murakami等考虑材料硬度、夹杂几何尺寸的影响率先提出了疲劳强度预测模型。随后,考虑应力比、累计损伤等因素的影响,部分学者也相继提出了一些修正模型。但是夹杂尺寸/分布、应力、寿命之间的关系仍没有得到很好的诠释。因此,十分有必要继续开展针对夹杂诱发疲劳失效的强度预测模型的研究。本文开展了渗碳Cr Mn齿轮钢的超高周疲劳试验研究,分析了其在超高周区的疲劳行为及破坏机理,探讨了诱发失效的内部夹杂尺寸、疲劳寿命、施加载荷之间的关系,同时基于广义帕雷托分布(generalized Pareto distribution,GPD)和广义统计极值分布(Generalized Extreme Values,GEV)对夹杂尺寸分布特性进行了比较分析,进而构建了一定概率条件下的夹杂尺寸-强度-寿命预测模型。结果表明,渗碳Cr Mn齿轮钢的疲劳失效主要包含加工缺陷诱发的表面失效以及夹杂诱发的内部失效;当疲劳寿命N>10时,内部夹杂诱发失效成为主要的破坏模式;建立的夹杂尺寸、应力幅值、疲劳寿命之间的关系能很好表征渗碳Cr Mn齿轮钢的中值S-N数据;从概率疲劳设计角度,基于GPD构建的概率夹杂尺寸-强度-寿命预测模型的预测结果偏于保守,而基于GEV构建模型的预测结果相对适合。

关键词：渗碳齿轮钢超高周疲劳夹杂统计分布疲劳强度

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Refining the Stratigraphy of the Taghdout Group by Using the U-Pb Geochronology of the Taghdout Sill(Zenaga inlier,Anti-Atlas,Morocco)

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Acta Geologica Sinica(English Edition) 2016年第S1期90卷 1-页

作者： abdelhak AIT LAHNA Colombo Celso Gaeta TASSINARI Nasrrddine YOUBI Hassan ADMOU Joao MATA El Hafid BOUOUGRI Latifa CHAIB Richard E.ERNST Ulf SODERLUND Moulay Ahmed BOUMEHDI Mohamed Khalil BENSALAH El Mostapha AARAB Department of Geology Faculty of Sciences-SemlaliaCadi Ayyad University Centro de Pesquisas Geocronológicas(CPGeo) Instituto de Geociencias(IG)Universidade de Sao Paulo-USP Instituto Dom Luiz Faculdade de CiênciasUniversidade de Lisboa Department of Earth Sciences Carleton University Department of Geology Lund University

The Anti-Atlas belt of southern Morocco is situated on the northern edge of the West African craton(WAC).It corresponds to a broad anticlinorium some 800 km long and 200 km wide,trending ENE-WSW,parallel to the

关键词： Pb Zenaga inlier Morocco Refining the Stratigraphy of the Taghdout Group by Using the U-Pb Geochronology of the Taghdout Sill Anti-Atlas

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