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Effects of cooling rate and B content on microstructure of near-eutectic Al-13wt%Si Alloy

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China Foundry 2008年第2期5卷 119-123页

作者： Xi Xiao Zhou Jianyuan Lü Jianhua The Sheet Trimming Plant of Second crm WISCO Wuhan 430080 Hubei China

Under cooling rates of 2 ℃/s and 10℃/s, the influences of B content on the microstructure of near eutectic Al-13.0wt%Si alloy have been investigated. Results showed that the addition of boron resulted in refinement of eutectic grains, and to some extent, had an inhibiting effect on precipitation of the primary phases, and the refining and inhibiting effects are much more obvious at higher cooling rate. When B was not added, higher cooling rate promoted the α-Al dendrites formation. At lower cooling rate, the addition of B did not cause the so called ＂columnar to equiaxed transition （CET）＂, however, at higher cooling rate, this transition was obvious. After the addition of B, the nucleation temperature TN ascended and nucleation mode changed from nucleation mode of from wall towards centre （without B addition） to a nucleation mode that the eutectic nucleated evenly throughout whole sample （with B added）. It can be concluded that the addition of B offers a large amount of nuclei for eutectic solidification, as a result, the eutectic grains was refined. Higher cooling rate will lead to more nuclei, so the effects on the refinement of eutectic grains and on suppression of primary phases are increased.

关键词： Al-Si alloy microstructure nucleation cooling rate

Bonding and Fracture Characteristics at α_2/γ Interface in TiAl Alloy with B Addition

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Journal of Materials Science & Technology 1999年第1期15卷 43-47页

作者： Senying LIU Dongliang ZHAO Rongze HU and Chongyu WANG(Central Iron and Steel Research Institute, Beijing 100081, China)Ping LUO(National Research Center for crm, Beijing 100013, China) Central Iron and Steel Research Institute Beijing 100081 China National Research Center for crm Beijing 100013 China

The bonding characteristics of (0001)α2||(111)γ interface in two-phase TiAl alloy have beeninvestigated with the recursion method. The results of bond order integral and interaction energybetween atoms are presented. The effects of B on atoms bonding both in constituent phase andat the α2/γ interface have been studied. The correlation between the mechanical propertiesof the alloy and the bonding at the interface has been discussed. The results suggest that Bsegregation to the interface benefits the ductility. This is supported by the related experiment.

关键词： TiAl Bonding and Fracture Characteristics at Interface in TiAl Alloy with B Addition

Distribution of atrial cardiomyopathy markers and association with atrial fibrillation detected after ischaemic stroke in the SAFAS study

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Stroke & Vascular Neurology 2024年第2期9卷 165-173,I0426,I0427页

作者： Romain Didier Lucie Garnier Gauthier Duloquin Alexandre Meloux Audrey Sagnard Mathilde Graber Geoffrey Dogon Karim Benali Thibaut Pommier Gabriel Laurent Catherine Vergely Yannick Bejot Charles Guenancia Cardiology CHU Dijon BourgogneDijonFrance Dijon Stroke Registry Department of NeurologyUniversity Hospital Centre DijonDijonFrance PEC 2 Universitéde BourgogneDijonFrance Cardiology CHU Saint EtienneSaint EtienneFrance

Background Atrial cardiomyopathy(AC)is an emerging concept explaining the pathophysiology of cardioembolic strokes in absence of atrial fibrillation(AF).A definition based on the presence of electrical abnormality(P-wave terminal force in lead V1(PTFV1)>5000µV×ms),N-Terminal pro-B-type natriuretic peptide(NT pro BNP)>250pg/mL and/or indexed left atrial diameter(LADI)>3cm/m^(2)is currently tested in the ARCADIA(AtRial Cardiopathy and Antithrombotic Drugs In prevention After cryptogenic stroke)*** set out to estimate the prevalence of AC as defined in the ARCADIA trial,its determinants and its association with AF detected after stroke(AFDAS).Methods Stepwise screening for silent Atrial Fibrillation After Stroke(SAFAS)study prospectively included 240 ischaemic stroke *** markers were complete for 192 of them and 9 were not included in this analysis because AF had been diagnosed on *** A total of 183 patients were analysed,of whom 57%(104 patients)met the AC criteria(79 NT-proBNP,47 PTFV1,4 LADI).In the multivariate logistic regression,C reactive protein>3mg/L(OR(95%CI)2.60(1.30 to 5.21),p=0.007)and age(OR(95%CI)1.07(1.04 to 1.10),p34mL/m^(2),OR 2.35(CI 1.09 to 5.06)p=0029).Conclusion AC as defined in ARCADIA is mostly based on NT pro BNP elevation(76%of patients)and is associated with age and ***,AC was not independently associated with AFDAS at *** ARCADIA trial,which compares aspirin to apixaban in patients with embolic strokes of undetermined source with AC markers and must,therefore be analysed in the light of these limitations.

关键词： atrial cardiomyopathy prevention

Pacemaker therapy in very elderly patients: survival and prognostic parameters of single center experience

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Journal of Geriatric Cardiology 2019年第12期16卷 880-884页

作者： Massimiliano Marini Marta Martin Michela Saltori Silvia Quintarelli Filippo Zilio Fabrizio Guarracini Alessio Coser Sergio Valsecchi Roberto Bonmassari Department of Cardiology S.Chiara HospitalTrentoItaly crm Department Boston ScientificMilanItaly

Background Permanent pacing is the therapy of choice for treating severe and/or symptomatic bradyarrhythmias. The number of very elderly patients receiving pacemakers is increasing and little is known about survival in this specific subgroup. This study is aimed at assessing the actual survival of patients requiring pacing therapy at age > 85 years and investigating variables associated with death. Methods Between 2010 and 2017, 572 patients aged ≥ 85 years underwent pacemaker implantation for conventional bradycardia indications in Department of Cardiology, S. Chiara Hospital, Italy. Results Thirty percent of patients were ≥ 90-year-old and comorbidities were frequent. Fifty-seven percent of patients required pacing for prognostic reasons(acquired atrioventricular block), and the remaining for relief of bradycardia symptoms. A dual-chamber pacemaker was implanted in 34% of patients. The 5-year survival was 45%(standard error: 3%), and the 8-year survival was 26%(standard error: 4%). The risk of death was similar in patients who received pacemaker for symptom relief and for prognostic reasons in the overall population(HR = 1.19, 95% CI: 0.93–1.52, P = 0.156), as well as in the ≥ 90-year-old group(HR = 1.39, 95% CI: 0.92–2.11, P = 0.102). At multivariate analysis, following variables were associated with death: higher age, lower ejection fraction, dementia/dysautonomia and diagnosis of cancer. The pacing indication and the implantation of a single chamber pacemaker were not associated with worse prognosis. Conclusions This study showed a good life expectancy in patients aged ≥ 85 years who received a pacemaker. Strong risk factors for all-cause death were non-cardiac. Pacemaker therapy seems a clinically effective therapeutic option to improve survival and to control bradyarrhythmia-related symptoms in very elderly patients.

关键词： Mortality Pacemaker The elderly

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SAP金融企业从客户关系突围

中外管理 2002年第7期 54-55页

作者：蒋歆 SAP中国crm

金融行业中,在所有与客户接触的地方与时间,都必须在实现客户信息完全集成的同时,认识到每个客户的个体差异。这样才能进行有针对性的营销和服务,抓住客户的心,从而在竞争中取胜。面临的问题要想做到这些。

关键词：营销服务金融企业客户关系 SAP

Synthesis, Characterization and Thermal Analysis of an Organic-Inorganic Hybrid Salt Involving Trans-Diaquabis(oxalato-κ2O1,O2)chromate(III) Complex Anion with Piperidinium as Counter Cation

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Crystal Structure Theory and Applications 2020年第2期9卷 36-47页

作者： Pierre R. Ndong Martin Signé Patrice T. Kenfack Yves A. Mbiangué Gouet Bebga Emmanuel Wenger Department of Inorganic Chemistry Faculty of Science University of Yaounde I Yaounde Cameroon Department of Chemistry Faculty of Science University of Dschang Dschang Cameroon Department of Chemistry Higher Teachers’ Training College University of Maroua Maroua Cameroon Department of Chemistry Higher Teachers’ Training College University of Yaounde I Yaounde Cameroon crm2 Université de Lorraine CNRS Nancy France

A new organic-inorganic hybrid salt pipéridinium trans-diaquabis(oxalato)- chromate(III) tetrahydrate, (C5H10NH2)[Cr(C2O4)2(H2O)2]·4H2O (1), has been synthesized in water and characterized by FTIR and UV-Vis spectroscopies, elemental and thermal analyses and by single-crystal X-ray diffraction. 1 crystallizes in the orthorhombic non-centrosymmetric space group Cmc21 with the unit cell parameters a = 7.4329(3), b = 9.9356(5), c = 23.6756(11) Å, α = β = γ = 90°, V = 1748.45(14) Å3 and Z = 4. The structure of 1 consists of [Cr(C2O4)2(H2O)2]- mononuclear anions, piperidinium cations and uncoordinated water molecules. The CrIII ion in the complex [Cr(C2O4)2(H2O)2]- is coordinated in a slightly distorted octahedral environment by four O atoms from two chelating oxalate dianions in the equatorial plane, and two O atoms from trans-coordinated water molecules occupying the apical positions. In the crystal, N-H···O and O-H···O hydrogen bond interactions connect the components into a 3-D framework. The IR spectrum of 1 is consistent with the presence of the various molecular building constituents, namely oxalato and aqua ligands, piperidinium cations and solvent water molecules. The UV-Vis spectrum shows two absorption bands around 564 and 416 nm which are compatible with an anionic chromium(III) complex in an octahedral environment. Thermal analysis shows a three-step decomposition of 1, leading to formation of a metal oxide residue.

关键词： Hybrid Salt Diaquabis(oxalato)chromate(III) Complex Crystal Structure Layered Structure Spectroscopy Thermal Analysis

A Novel Chromium(III) Hybrid Salt, Triethylammonium Trans-Diaquabis(Oxalato-κ2O1,O2) Chromate(III), (C6H16N)[Cr(C2O4)2(H2O) 2]: Synthesis, Spectroscopic Studies, Thermal Behavior and Crystal Structure

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Open Journal of Inorganic Chemistry 2020年第4期10卷 39-51页

作者： Pierre R. Ndong Martin Signé Patrice T. Kenfack Yves A. Mbiangué Gouet Bebga Emmanuel Wenger Department of Inorganic Chemistry Faculty of Science University of Yaounde I Yaounde Cameroon Department of Chemistry Faculty of Science University of Dschang Dschang Cameroon Department of Chemistry Higher Teachers’ Training College University of Maroua Maroua Cameroon Department of Chemistry Higher Teacher Training College University of Yaounde I Yaounde Cameroon crm² Université de Lorraine CNRS Nancy France

A novel organic-inorganic chromium(III) hybrid salt, triethylammonium trans-diaquabis(oxalato-κ2O1,O2)chromate(III), (C6H16N)[Cr(C2O4)2(H2O)2] (1), has been synthesized in aqueous solution and characterized by elemental and thermal analyses, FTIR and UV-Vis spectroscopies, and by single crystal X-ray structure determination. Compound 1 crystallizes in the orthorhombic system, Pbcn space group with the unit cell parameters a = 11.1776(10), b = 7.6105(10), c = 17.5654(2) Å, α = β = γ = 90°, V = 1494.24(3) Å3, Z = 4 and Z’ = 1/2. The structure of 1 consists of [Cr(C2O4)2(H2O)2]− mononuclear anions and triethylammonium [(C2H5)3NH]+ cations. In the anionic unit, the CrIII ion is six coordinated, in a distorted octahedral geometry, by four equatorial O atoms of two oxalate anions acting as chelating ligands and two O atoms from trans-coordinated water molecules occupying the apical positions with longer metal-oxygen distances. In the solid, O-H … O and N-H … O intra and inter molecular hydrogen bonding interactions connect the components into a 3D network. The triethylammonium cations are disordered among two possible orientations with occupancies rates around 50% for C4, N1, C1a, C1b, C4ii, N1ii, C1aii, C1bii (ii = −x + 1, y,

关键词： Hybrid Salt Chromium(III) Oxalate Complex Triethylammonium Static Disorder Spectroscopy Crystal Structure Thermal Study

Validation of a Marker of Atrial Contraction in the SonR Signal

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World Journal of Cardiovascular Diseases 2015年第3期5卷 53-61页

作者： Florent Broussous Adonis Kobeissi Jérome Dumont Fabrizio Renesto Jacques Mansourati Cardiology Department University Hospital La Cavale BlancheBrestFrance Sorin Group crm France ClamartFrance Sorin crm SAS ClamartFrance Sorin crm Srl SaluggiaItaly EA 4324 ORPHYUniversite de Bretagne OccidentaleBrestFrance

Introduction: The main component of the endocardial acceleration signal (SonR) is today used for cardiac resynchronization therapy (CRT) optimization. This prospective, single center pilot study focuses on another signal component, SonR4 that may provide further information on the atrial activity. Methods and Results: SonR signal and ECG tracings were recorded simultaneously during a CRT-D optimization procedure in 15 patients (12 men, 68 ± 9.5 years, ischemic heart disease 53%) indicated for CRT. Correlation between SonR4 signal, recorded using SonR and atrial contraction, identified by Echo Doppler was evaluated by Pearson and Student’s t tests under different Atrio-Ventricular (AV) delay programming. From 15 consecutive screened patients, 9 had concomitant analyzable SonR4 and ECG recordings and were included in the study population. The presence of the SonR4 component was systematically correlated to the presence of the A wave. A significant correlation was observed between SonR4 and A wave timings (r = 0.75, p = 0.02) according to different AV delays, with a high reproducibility in SonR4 assessment. Conclusion: A strong correlation between SonR4 and atrial contraction timings was observed, further suggesting that SonR4 is a marker of the atrial contraction. Additional assessments in larger populations are required to confirm these results and build further applications.

关键词： Endocardial Acceleration(EA) Hemodynamic Sensor SonR Cardiac Resynchronization Therapy Heart Sound Atrial Contraction

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服务管理:ERP、crm后的“特种部队”

中国计算机用户 2003年第7期 29-29,31页

作者：贾月娥 crm顾问

企业之间服务的竞争正在成为竞争的焦点。于是,服务在逐步成为企业获取利润主要来源的同时,如何开展“服务管理”被越来越关注。如何确保企业“无处不在的服务”等服务理念真正落实到可量化、可感知,使无形的服务“有型化”,使不可与产... 详细信息

企业之间服务的竞争正在成为竞争的焦点。于是,服务在逐步成为企业获取利润主要来源的同时,如何开展“服务管理”被越来越关注。如何确保企业“无处不在的服务”等服务理念真正落实到可量化、可感知,使无形的服务“有型化”,使不可与产品分离的服务生产率逐步提高,已不再是嘴上功夫,而是一场真枪实弹的革命。

关键词：企业服务管理 crm ERP 服务生产率利润产品特种部队无形获取