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Remarkable catalysis of spinel ferrite XFe2O4(X=Ni,Co,Mn,Cu,Zn)nanoparticles on the dehydrogenation properties of LiAlh_(4):An experimental and theoretical study

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Journal of Materials Science & Technology 2022年第16期111卷 189-203页

作者： Sheng Wei Jiaxi Liu Yongpeng Xia huanzhi Zhang Riguang Cheng Lixian Sun Fen Xu Pengru huang Federico Rosei Aleskey A.Pimerzin hans Jüergen seifert hongge Pan School of Material Science&Engineering Guangxi Key Laboratory of Information Materials and Guangxi Collaborative Innovation Center of Structure and Property for New Energy and MaterialsGuilin University of Electronic TechnologyGuilin 541004China School of Mechanical&Electrical Engineering Guilin University of Electronic TechnologyGuilin 541004China CentreÉnergie Matériaux et TélécommunicationsInstitut National de la Recherche Scientifique1650 Boul.Lionel BouletVarennesJ3×1S2QuébecCanada Samara State Technical University Samara443100Russia Institute for Applied Materials Karlsruhe Institute of TechnologyHermann von Helmholtz Platz 176344 Eggenstein LeopoldshafenGermany School of New Energy Science and Technology Xi’an Technological UniversityXi’an 710021China

Safe,compact,lightweight and cost-effective hydrogen storage is one of the main challenges that need to be addressed to effectively deploy the hydrogen economy.LiAlh_(4),as a solid-state hydrogen storage material,presents several advantages such as high hydrogen storage capacity,low price and abundant sources.Unfortunately,neither thermodynamic nor kinetic properties of dehydrogenation for LiAlh_(4)can fulfill the requirements of practical application.Thus,a series of spinel ferrite nanoparticles such as XFe_(2)O_(4)(X=Ni,Co,Mn,Cu,Zn,Fe)were prepared by using the modified thermal decomposition method,and then doped into LiAlh_(4)by using ball milling.Our results show that LiAlh_(4)doped with 7 wt%NiFe_(2)O_(4)starts to release hydrogen at 69.1°C,and the total amount of hydrogen released is 7.29 wt%before 300°C.The activation energies of the two-step hydrogen release reactions of LiAlh_(4)doped with 7 wt%NiFe_(2)O_(4)are 42.32 kJ mol^(-1)and 71.42 k J mol,which are 59.0%and 63.6%lower than those of as-received LiAlh_(4),respectively.Combining the density functional theory(DFT)calculations,we reveal that both the presence of Ni FeOand in-situ formed AlNiin ball-milling decrease the desorption energy barrier of Al-h bonding in LiAlh_(4)and accelerate the breakdown of Al-h bonding through the interfacial charge transfer and the dehybridization of the Al-h cluster.Thus,the experimental and theoretical results open a new avenue toward designing high effective catalysts applied to LiAlh_(4)as a candidate for hydrogen storage.

关键词： hydrogen storage Lithium aluminum Spinel ferrite nanoparticles

Rhythmical massage improves autonomic nervous system function:a single-blind randomised controlled trial

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Journal of Integrative Medicine 2018年第3期16卷 172-177页

作者： Georg seifert Jenny-Lena Kanitz Carolina Rihs Ingrid Krause Katharina Witt Andreas Voss Department of Pediatric Oncology and hematology Charité-Universit?tsmedizin Berlin Institute of Innovative health Technologies Ernst-Abbe-Hochschule University of Applied Sciences

Background： Rhythmical massage therapy（RMT） is a massage technique used in anthroposophic medicine.Objective： The authors aimed to investigate the physiological action of RMT on the cardiovascular system by analysing heart rate variability（hRV）.Design, setting, participants and intervention： This study was a randomised, controlled and single-blinded trial, involving 44 healthy women（mean age：（26.20 ± 4.71） years）. The subjects were randomised to one of three arms： RMT with aromatic oil（RA）, RMT without aromatic oil（RM） or standardised sham massage（SM）. In the study the subjects were exposed to a standardised stress situation followed by one of the study techniques and holter electrocardiograms（ECGs） were recorded for 24 h.Main outcome measures： hRV parameters were calculated from linear（time and frequency domain） and nonlinear dynamics（symbolic dynamics, Poincare plot analysis） of the 24-h holter ECG records.Results： Short-and long-term effects of massage on autonomic regulation differed significantly among the three groups. Immediately after an RMT session, stimulation of hRV was found in the groups RA and RM. The use of an aromatic oil produced greater short-term measurable changes in hRV compared with rhythmic massage alone, but after 24 h the effect was no longer distinguishable from the RM group.The lowest stimulation of hRV parameters was measured in the SM group.Conclusion： RMT causes specific and marked stimulation of the autonomic nervous system. Use of a medicinal aromatic oil had only a temporary effect on hRV, indicating that the RM causes the most relevant long-term effect. The effect is relatively specific, as the physiological effects seen in the group of subjects who received only SM were considerably less pronounced.

关键词： Sham massage Well-being Mood Alertness Relaxation Stress heart rate variability Randomised controlled trial

Subsolidus Phase Relations in the System MgO-SiO_2-Cr-O and Thermodynamic Properties of Related Cr^(2+)-Containing End-members

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Acta Geologica Sinica(English Edition) 1996年第4期70卷 420-434页

作者： h.St.CO' Neill F.seifert Bayerisches Geoinstitut Universit t Bayreuth GermanyBayerisches Geoinstitut Universit t Bayreuth Germany

Subsolidus phase relations have been determined in the systems SiO2-Cr-O and MgO-SiO2-Cr-O in equilibrium with metallic Cr, at 1100 to 1500℃ and 0 to 2.88 GPa. The results show that there are no ternary phases in the SiO2-Cr-O system at these conditions, i.e., only the assemblage eskolaite-Cr-metal-quartz (or tridymite) is found. In the MgO-containing system, however, extensive substitution of Cr2+ for Mg is observed in (Mg, Cr2+)2SiO4 olivine, (Mg, Cr2+)2Si2O6 pyroxene, and (Mg, Cr2+)Cr2O4 spinel. Cr3+ levels in olivine and pyroxene are below detection limits. The pyroxene is orthohombic at XCrPx2+ higher XCrPx2+ . Thestructure of the spinels becomes tetragonally distorted at XCr2+Sp >0.2. The experimental datahave been fitted to a thermodynamic model, and the authors obtained the mixing parameter (W) of Mg-Cr2+ in olivine, pyroxene and spinel, and the relation between temperatures and free energies of formation for the end-members: Cr2+-olivine (Cr2SiO4), Cr2+-pyroxene (Cr2Si2O6) and Cr2+-spinel (Cr3O4).

关键词： MgO-SiO_2-Cr-O system phase equilibrium thermodynamic properties

Significant decrease in prevalence ofhelicobacter pylori in the Czech Republic

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World Journal of Gastroenterology 2012年第32期18卷 4412-4418页

作者： Jan Bure Marcela Kopáová Ilona Koupil Bohumil seifert Miluka kodová Fendrichová Jana pirková Viktor Voíek Stanislav Rejchrt TomáDouda Norbert Král Ilja Tachecí Second Department of Medicine Gastroenterology Charles University in PrahaFaculty of Medicine at Hradec KrálovéUniversity Teaching Hospital50005 Hradec KrálovéCzech Republic Centre for health Equity Studies Karolinska InstituteStockholm University17177 StockholmSweden First Faculty of Medicine Institute of General PracticeCharles University12108 PrahaCzech Republic Institute of Clinical Biochemistry and Diagnostics Charles University in PrahaFaculty of Medicine at Hradec KrálovéUniversity Teaching Hospital50005 Hradec KrálovéCzech Republic

AIM:To study possible decrease in prevalence of helicobacter pylori(h.pylori) infection in the Czech Republic within a 10-year period.METhODS:A total of 22 centres entered the study.The catchment areas of these centres covered cities and towns with more than 20 000 inhabitants,smaller towns(≤ 20 000 inhabitants) with surrounding villages and rural areas,and were spread over the whole country,corresponding well to the geographical distribution of the Czech population.A total of 1 837 subjects(aged 5-98 years) took part in the study,randomly selected out of 38 147 people from the general population.h.pylori infection was investigated by means of a 13 C-urea breath test.Breath samples in duplicates were analysed using isotope ratio mass spectrometry.The cut-off point was 3.5.Social and demographic characteristics were based on data from self-completed questionnaires.RESULTS:The overall prevalence of h.pylori infection was 23.5%(430/1826),and 4.8%(20/420) in children aged 15 or less.There was no statistically significant difference in prevalence between males(24.3%;208/857) and females(22.9%,222/969,P = 0.494).h.pylori infection was strongly associated with higher age,among subjects aged 55+ years,prevalence of h.pylori infection was 39.8%(252/633,P he highest prevalence of h.pylori infection was found among persons aged 55-64 years(43.9%,97/221) and 75+ years(37.9%,58/153).Among study subjects aged 15+ years,prevalence of h.pylori infection was significantly increased in those with lowest education(odds risk 3.19,95% CI 1.87-5.47).Compared to never married(14.1%),the prevalence of h.pylori infection was statistically significantly higher among married(35.4%,246/694,P h in minimally and fully adjusted analysis.There was no significant difference in the prevalence of h.pylori infection between married and widowed subjects(35.4%,246/694 vs 40.2%,45/112,P = 0.389).There was little variation in smoking prevalence acr

关键词：幽门螺旋杆菌捷克共和国患病率城镇人口吸烟率农村地区地理分布质谱分析

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拓扑学

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Parameterization Modeling of a Gas Turbine Coverplate

1959年

作者：（德）沙爱福seifert h.（德）施雷发Threlfall W. 江泽涵译

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Journal of Energy and Power Engineering 2014年第8期8卷 1378-1385页

作者： Nacim Mesbah Sandy seifert Bruno Chatelois Francois Gamier hany Moustapha Bell helicopter Textron Canada Mirabel J7J 1R4 Canada Alstom Switzerland Ltd. Baden 5400 Switzerland Pratt & Whitney Canada Longueuil J4G 1A 1 Canada Ecole de technologie superieure Montreal H3C IR9 Canada

In order to reduce product development cycle time, aerospace companies tend to develop various correlations integrating geometric and performance parameters. This paper covers the development of a parameterization modeling, to be used in the preliminary design phase, for the turbine cover plate of an aero-engine. The parameterization modeling of the turbine cover plate is achieved by using commercial CAD (computer aided design) software processing in batch mode. Two main approaches are presented: the outer face and the skeleton models. These models can then be integrated into an iterative process for designing optimal shapes. Both models are capable of reproducing existing cover plate with reasonable accuracy in relatively shorter time periods. however, the skeleton approach provides probably the best results in terms of flexibility and accuracy, but increases programming complexity and requires greater run times.

关键词：参数化建模盖板燃气轮机产品开发周期计算机辅助设计航空发动机设计阶段骨架模型

MgO-SiO_2-Cr-O体系的亚固相相关系及有关含Cr^(2+)端员矿物的热力学特征

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地质学报 1996年第2期70卷 173-185页

作者：李建平 h.StC0'Neill F.seifert 中国科学院广州地球化学研究所德国拜罗伊特大学地质研究所

在t=1100-1500℃和P=0-2.88GPa条件下,实验确定了与金属Cr平衡的SiO_2-Cr-O及MgO-SiO_2-Cr-O体系中的亚固相相关系。结果显示,在SiO_2-Cr-O体系中,只发现绿铬矿-金属铬-石英(或鳞石英)组合;而在含MgO体系中,出现Mg-Cr^(2+)橄榄石、辉石... 详细信息

在t=1100-1500℃和P=0-2.88GPa条件下,实验确定了与金属Cr平衡的SiO_2-Cr-O及MgO-SiO_2-Cr-O体系中的亚固相相关系。结果显示,在SiO_2-Cr-O体系中,只发现绿铬矿-金属铬-石英(或鳞石英)组合;而在含MgO体系中,出现Mg-Cr^(2+)橄榄石、辉石及尖晶石固溶体。Cr^(3+)在橄榄石和辉石中的含量在可测定限度之下。当X_(Cr^(2+))=[Cr^(2+)/(Mg+Cr^(2+))]>0.2时,辉石的结构由斜方晶系转为单斜晶系;尖晶石的结构由立方变为四方。对实验数据进行热力学模拟,求得Mg-Cr^(2+)在橄榄石,辉石及尖晶石固溶体中的混合参数(W),以及铬橄榄石(Cr_2SiO_4)、铬辉石(Cr_2Si_2O_6)和铬尖晶石(Cr_3O_4)的形成自由能(△G°)与温度的关系。

关键词： MgO-SiO2-Cr-O 相平衡热力学特征铬矿

Blood pressure and stature in helicobacter pylori positive and negative persons

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World Journal of Gastroenterology 2014年第19期20卷 5625-5631页

作者： Marcela Kopacova Ilona Koupil Bohumil seifert Miluska Skodova Fendrichova Jana Spirkova Viktor Vorisek Stanislav Rejchrt Tomas Douda Ilja Tacheci Jan Bures 2~(nd)Department of Internal Medicine-Gastroenterology Charles University in PrahaFaculty of Medicine at Hradec KraloveUniversity Teaching Hospital50005 Hradec KraloveCzech Republic Centre for health Equity Studies Stockholm UniversityKarolinska Institute17177 StockholmSweden Institute of General Practice First Faculty of MedicineCharles University12002 PrahaCzech Republic Institute of Clinical Biochemistry and Diagnostics Charles University in PrahaFaculty of Medicine at Hradec KraloveUniversity Teaching Hospital50005 Hradec KraloveCzech Republic

To evaluate vital signs and body indices in helicobacter pylori(h.pylori)positive and negative persons.A total of 22 centres entered the study.They were spread over the whole country,corresponding well to the geographical distribution of the Czech population.A total of 1818 subjects(aged 5-98 years)took part in the study,randomly selected out of 38147 subjects.h.pylori infection was investigated by means of a 13Curea breath test.Data on height,weight,systolic and diastolic blood pressure and heart rate were collected at the clinics of general practitioners.The overall prevalence of h.pylori infection was 30.4%(402/1321)in adults(≥18 year-old)and 5.2%(26/497)in children and adolescents(≤17 year-old).Once adjusted for age and gender,only a difference in body mass index remained statistically significant with h.pylori positive adults showing an increase of 0.6 kg/m2 in body mass index.Once adjusted for age and gender,we found a difference in height between h.pylori positive and h.pylori negative children and adolescents.On further adjustment for place of residence,this difference became statistically significant,with h.pylori positive children and adolescents being on average 3.5 cm shorter.h.pylori positive adults were significantly older compared to h.pylori negative subjects.Once adjusted for age and gender,h.pylori infection had no impact on body weight,body mass index and vital signs either in adults or children and adolescents.Chronic h.pylori infection appeared to be associated with short stature in children.h.pylori infection did not influence blood pressure,body weight and body mass index either in adults or children and adolescents.

关键词： Epidemiology helicobacter pylori Czech Republic 13

肝动脉栓塞治疗遗传性出血性毛细血管扩张症的并发症及临床结果

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国际医学放射学杂志 2013年第3期 297-298页

作者： A.Chavan L.Luthe M.Gebel h.Barg-hock h.seifert R.Raab 徐后云 Department of Diagnostic and Interventional Radiology Klinikum Oldenburg

背景遗传性出血性毛细血管扩张症(hhT)病人行肝动脉栓塞(hAE)治疗目前仍有争议,主要原因是与手术相关的并发症及未被证实的远期疗效。研究了17年里收治的20个遗传性出血性毛细血管扩张症病人行肝动脉栓塞的治疗结果。方法肝动脉栓塞均... 详细信息

背景遗传性出血性毛细血管扩张症(hhT)病人行肝动脉栓塞(hAE)治疗目前仍有争议,主要原因是与手术相关的并发症及未被证实的远期疗效。研究了17年里收治的20个遗传性出血性毛细血管扩张症病人行肝动脉栓塞的治疗结果。方法肝动脉栓塞均使用聚乙烯醇(PVA)颗粒和钢圈,术前、术后及随访结束时均评估病人的并发症、临床症状以及心输出量,平均随访时间为92个月(26～208个月)。结果其中2例病人在肝动脉栓塞术后30d内死亡(10%),另外有4例死亡病人的死因与肝动脉栓塞术无关。有4例病人因缺血性胆管炎、胆囊炎及局灶性肝坏死伴胆源性败血症而需要再次干预治疗。在随访结束时,除1例病人外,其他所有病人的平均心输出量从治疗前的(11.84±3.22)L/min下降至(8.13±2.67)L/min(P<0.001),由此引起的临床症状得到缓解。其中1例病人经肝动脉栓塞治疗后4年,因新发的门静脉高压症状而需要肝脏移植。结论遗传性出血性毛细血管扩张症病人行肝动脉栓塞治疗后30d死亡率为10%,需要再次干预治疗的并发症发生率为20%,远期随访的临床反应是满意的。要点①肝动脉栓塞治疗遗传性出血性毛细血管扩张症具有远期受益。②肝动脉栓塞治疗遗传性出血性毛细血管扩张症的死亡率与肝移植相似。③对于遗传性出血性毛细血管扩张症来说,肝动脉栓塞治疗的并发症低于肝移植。④肝动脉栓塞并发症的发生率可以通过技术的提高而进一步降低。⑤肝动脉栓塞治疗遗传性出血性毛细血管扩张症的并发症包括缺血性胆管炎、肝坏死、胆源性败血症及死亡。

关键词：栓塞治疗动静脉畸形心力衰竭胆道疾病肝移植