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Trace element characteristics of partial melts produced by melting of metabasalts at high pressures: Constraints on the formation condition of adakitic melts

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Science China Earth Sciences 2006年第9期49卷 915-925页

作者： J. Adam T.h. Green GEMOC National Key Centre Department of Earth and Planetary Sciences Macquarie University Sydney NSW 2109 Australia GEMOC National Key Centre Department of Earth and Planetary Sciences Macquarie University Sydney NSW 2109 Australia

Experiments were conducted on a natural basalt (with 5 wt.% added h2O) at 1.0―2.5 GPa and 900―1100℃. Experimental products include partial melts (quenched glasses) + residual mineral assemblages of amphibolite or eclogite. Electron microprobe and LAM-ICP-MS were used to determine major and trace element compositions of these quenched melts, respectively. Major ele- ment compositions of all the melts are tonalitic- trondhjemitic, similar to adakite. Their trace element characteristics are controlled by coexisting residual minerals. Signatures of adakite such as high Sr/Y, low hREE and negative Nb-ta anomaly, etc. are present only in the melts coexisting with residual assemblages containing rutile and garnet (rutile-bearing eclogite or rutile-bearing amphibole-eclogite). Garnet leads to hREE depletion in melts, whereas rutile controls Nb and ta partitioning during the partial melting and causes negative Nb-ta anomaly in melts. Therefore, in addition to garnet, rutile is also a necessary residual phase during the generation of adakite or TTG magmas to account for the negative Nb-ta anomaly of the magmas. The depth for the generation of adakite/TTG magmas via melting of metabasalt must be more than about 50 km based on the approximate 1.5 GPa mini- mum-pressure for rutile stability in the partial melting field of hydrous basalt.

关键词： trace element adakite/TTG magmas partial melting of metabasalt negativeNb-ta anomaly rutile

Overcoming the strength-ductility trade-off by tailoring grain-boundary metastable Si-containing phase in β-type titanium alloy

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Journal of Materials Science & Technology 2021年第9期68卷 112-123页

作者： X.Luo L.h.Liu C.Yang h.Z Lu h.W.Ma Z.Wang D.D.Li L.C.Zhang Y.Y.Li National Engineering Research Center of Near-net-shape Forming for Metallic Materials South China University of TechnologyGuangzhou510640China State Key Laboratory of Materials Processing and Die&Mould Technology Huazhong University of Science and TechnologyWuhan430074China Key Laboratory of Automobile Materials of MOE Department of Materials ScienceJilin UniversityChangchun130012China School of Engineering Edith Cowan University270Joondalup DriveJoondalupPerthWA 6027Australia

It is well accepted that grain-boundary phases in metallic alloys greatly deteriorate the mechanical *** our work,we report on a novel strategy to prepare high strength-ductility β-type(Ti69.71 Nb23.72Zr4.83ta1.74)97Si3(at.%)(TNZTS) alloys by tailoring grain-boundary metastable Si-containing ***,the thin shell-shaped metastable S1 phase surrounding the columnar β-Ti grain was intercepted successfully via nonequilibrium rapid solidification achieved by selective laser melting(SLM).Subsequently,the thin shell-shaped metastable(Ti,Nb,Zr)5 Si3(called S1) phase was transformed into globular(Ti,Nb,Zr)2 Si(called S2) phase by the solution heat ***,the globular S2 phases reinforced TNZTS alloy exhibits ultrahigh yield strength of 978 MPa,ultimate strength of 1010 MPa and large elongation of 10.4 %,overcoming the strength-ductility trade-off of TNZTS alloys by various ***,the reported yield strength herein is 55 % higher than that of conventionally forged TNZT *** analysis indicates the globularization process of the metastable S1 phase is controlled by the model of termination *** quantitative analysis on strengthening mechanism demonstrates that the increase in yield strength of the heat-treated alloys is mainly ascribed to the strengthening of the precipitated silicide and the dislocations induced by high cooling *** obtained results provide some basis guidelines for designing and fabricating β-titanium alloys with excellent mechanical properties,and pave the way for biomedical application of TNZTS alloy by SLM.

关键词： Selective laser melting βtitanium alloys heat treatment

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基于GPS和里程计的快速行进间粗对准方法

北京航空航天大学学报 2017年第1期43卷 121-127页

作者：塔高明宋来亮冉龙俊北京航空航天大学仪器科学与光电工程学院北京100083

针对车载捷联惯导系统(SINS),提出一种快速行进间粗对准方法。将捷联矩阵分解为3个矩阵相乘,利用GPS提供的载体在导航坐标系的速度和里程计提供的载体在载体坐标系的速度构建不共线向量,求解初始载体坐标系相对惯性坐标系的常值转换矩阵... 详细信息

针对车载捷联惯导系统(SINS),提出一种快速行进间粗对准方法。将捷联矩阵分解为3个矩阵相乘,利用GPS提供的载体在导航坐标系的速度和里程计提供的载体在载体坐标系的速度构建不共线向量,求解初始载体坐标系相对惯性坐标系的常值转换矩阵,进而求得初始姿态矩阵。该对准方法对载车的唯一要求是在对准过程中做一个转弯机动。与现有对准方法相比,该方法没有用到加速度计信息。仿真结果表明,该方法能在1 min之内完成粗对准,采用零偏为0.1(°)/h的低精度陀螺,对准误差小于0.3°。

关键词：粗对准 GPS 里程计不共线的向量转弯机动

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阳离子淀粉物理形貌及流变性的影响因素

天津工业大学学报 2011年第2期30卷 46-49页

作者：李广芬塔娜天津工业大学材料科学与工程学院天津300160

将玉米淀粉、醚化剂和碱以一定比例进行机械混合,并在加热条件下进行干法反应以制备低取代度阳离子淀粉.研究表明:反应条件如醚化剂用量、NaOh用量、反应时间和反应温度对阳离子化玉米淀粉的物理形貌及流变性能有着很大的影响,阳离子淀... 详细信息

将玉米淀粉、醚化剂和碱以一定比例进行机械混合,并在加热条件下进行干法反应以制备低取代度阳离子淀粉.研究表明:反应条件如醚化剂用量、NaOh用量、反应时间和反应温度对阳离子化玉米淀粉的物理形貌及流变性能有着很大的影响,阳离子淀粉的糊液黏度会随醚化剂加入量的增加呈先升高后下降的趋势,而NaOh加入量的增加使得阳离子淀粉的糊液黏度有少许下降;在反应温度介于35～55℃时,延长反应时间有利于黏度的提高;产品在反应温度45℃下反应4 h后,阳离子淀粉的糊液黏度趋于稳定.对比原淀粉及阳离子化淀粉的扫描电子显微镜图发现,变性后的淀粉颗粒表面形态有了较大的变化,原淀粉的晶体结构被破坏,颗粒粒径分布范围增大,颗粒表面呈现粘连现象.采用红外光谱与DSC对部分样品进行测试表明,淀粉变性后其内部基团种类基本未发生改变,但部分基团的数量确有所增加.

关键词：阳离子淀粉物理形貌流变性醚化干法黏度

UV/h_2O_2/草酸高铁铵对甲苯胺蓝的降解作用

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印染 2011年第11期37卷 12-15页

作者：张昕塔娜内蒙古师范大学化学与环境学院环境科学研究所内蒙古呼和浩特010022

研究采用UV、h2O2、草酸高铁铵体系处理甲苯胺蓝(Toluidine blue,简称为TB)溶液的降解作用。考察了TB初始浓度、初始ph值、h2O2浓度、草酸高铁铵浓度对TB降解率的影响。试验结果表明,酸性条件有利于TB的降解,其最佳降解ph值为4.0。在UV/... 详细信息

研究采用UV、h2O2、草酸高铁铵体系处理甲苯胺蓝(Toluidine blue,简称为TB)溶液的降解作用。考察了TB初始浓度、初始ph值、h2O2浓度、草酸高铁铵浓度对TB降解率的影响。试验结果表明,酸性条件有利于TB的降解,其最佳降解ph值为4.0。在UV/h2O2体系中,h2O2浓度在100 mmol/L时,TB降解率相对高;UV/草酸高铁铵体系中,草酸高铁铵浓度为10.0 mmol/L时TB降解率较高;相比于其它体系,UV/h2O2/草酸高铁铵体系的降解效果最好,降解率可达88.62%。

关键词：染整废水处理降解脱色

Leaching of rare earths from fine-grained zirconosilicate ore

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Journal of Rare Earths 2016年第9期34卷 908-916页

作者： h.Lim D.Ibana J.Eksteen Western Australia School of Mines Curtin University7 Conlon StreetWaterford6152 Australia Mining and Metallurgy Western Australia School of MinesLocked Bag l7Kalgoorlie6433Australia

Leaching of rare earths Y, La and Ce by sulphuric acid from fine-grained zirconosilicate ore was investigated using ta-guchi method of experimental design. An orthogonal array of L8, 27 which denotes 7 factors at 2 levels was chosen to consider the various factors relevant to the leaching process： baking time, baking temperature, acid dosage, leaching time, leaching temperature, grind size and dilution. Statistical analysis showed that sulphation baking was a significant step for the leaching of rare earths from the whole-of-ore and optimized leaching of rare earths involved the following condition： baking for 3 h at 320 ℃ at 3.2 g acid/g ore acid dosage followed by water leaching at 20 ℃ for 1 h and dilution of 20 mL water/g ore using 300 um grind size. The effect of each leaching factor was also discussed.

关键词： rare earths yttrium lanthanum cerium zirconosilicate leaching taguchi

highly dispersed nickel species on iron‐based perovskite for CO_(2) electrolysis in solid oxide electrolysis cell

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Chinese Journal of Catalysis 2022年第7期43卷 1710-1718页

作者： Yingjie Zhou Tianfu Liu Yuefeng Song houfu Lv Qingxue Liu Na ta Xiaomin Zhang Guoxiong Wang State Key Laboratory for Modification of Chemical Fibers and Polymer Materials College of Materials Science and EngineeringDonghua UniversityShanghai 201620China State Key Laboratory of Catalysis CAS Center for Excellence in NanoscienceDalian National Laboratory for Clean EnergyDalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023LiaoningChina University of Chinese Academy of Sciences Beijing 100049China

Feasible construction of cathode materials with highly dispersed active sites can extend the tri‐ple‐phase boundaries,and therefore leading to enhanced electrode kinetics for CO_(2) electrolysis in solid oxide electrolysis cell(SOEC).herein,highly dispersed nickel species with low loading(1.0 wt%)were trapped within the La_(0.8)Sr_(0.2)FeO_(3)–δ‐Ce_(0.8)Sm_(0.2)O_(2)–δvia a facial mechanical milling ap‐proach,which demonstrated excellent CO_(2) electrolysis *** highly dispersed nickel species can significantly alter the electronic structures of the LSF‐SDC without affecting its porous network and facilitate oxygen vacancy formation,thus greatly promote the CO_(2) electrolysis perfor‐*** highest current density of 1.53 A·cm^(-2) could be achieved when operated under 800℃ at 1.6 V,which is about 91%higher than the LSF‐SDC counterpart.

关键词： CO_(2)electrolysis Solid oxide electrolysis cells Perovskite oxide Nickel species

Candidate Eclipsing Binary Systems with a δ Scuti Star in Northern TESS Field

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Research in Astronomy and Astrophysics 2022年第8期22卷 36-50页

作者： F.Kahraman Ali?avu? D.Gümü? ?.K?rm?z?ta? ?.Ekinci S.?avu? Y.T.Kaya F.Ali?avu? ?anakkale Onsekiz Mart University Faculty of Sciences and Arts Physics Department ?anakkale Onsekiz Mart University Astrophysics Research Center and Ulupnar Observatory Istanbul University Institute of Graduate Studies in Science Programme of Astronomy and Space Sciences ?anakkale Onsekiz Mart University School of Graduate Studies Department of Physics ?anakkale Onsekiz Mart University School of Graduate Studies Department of Space Sciences and Technologies ?anakkale Onsekiz Mart University Faculty of Engineering Computer Engineering

The existence of pulsating stars in eclipsing binaries has been known for decades. These types of objects are extremely valuable systems for astronomical studies as they exhibit both eclipse and pulsation variations. The eclipsing binaries are the only way to directly measure the mass and radius of stars with a good accuracy(≤1%),while the pulsations are a unique way to probe the stellar interior via oscillation frequencies. There are different types of pulsating stars existing in eclipsing binaries. One of them is the δ Scuti variables. Currently, the known number of δ Scuti stars in eclipsing binaries is around 90 according to the latest catalog of these variables. An increasing number of these kinds of variables is important to understand the stellar structure, evolution and the effect of binarity on the pulsations. Therefore, in this study, we focus on discovering new eclipsing binaries with δ Scuti component(s). We searched within the northern Transiting Exoplanet Survey Satellite(TESS) field with a visual inspection by following some criteria such as light curve shape, the existence of pulsation like variations in the out-of-eclipse light curve and the Teffvalues of the targets. As a result of these criteria, we discovered some targets. The orbital variations were first removed from the TESS light curves and frequency analysis was performed on the residuals. The luminosity, and absolute and bolometric magnitudes of the targets were calculated as well. To find how much of these parameters represent the primary(more luminous) binary component, we also computed the flux density ratio of the systems by utilizing the area of the eclipses. In addition, the positions of the systems in the h-R diagram were examined considering the flux density ratios. As a consequence of the investigation, we defined 38 candidate δ Scuti stars and also one Maia variable in eclipsing binary systems.

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不同浓度罗哌卡因对剖宫产术后镇痛效应及安全性研究

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中国临床药理学杂志 2019年第22期35卷 2830-2832,2839页

作者：徐军方建塔杭州市富阳区第二人民医院麻醉科

目的观察不同浓度罗哌卡因经腹横筋膜平面阻滞对剖宫产术后镇痛效应及安全性。方法入选进行剖宫产手术的产妇126例,术后均进行经腹横筋膜平面阻滞,根据罗哌卡因用量的不同分为3组,A组注入0.45%罗哌卡因20m L;B组注入0.35%罗哌卡因20 m ... 详细信息

目的观察不同浓度罗哌卡因经腹横筋膜平面阻滞对剖宫产术后镇痛效应及安全性。方法入选进行剖宫产手术的产妇126例,术后均进行经腹横筋膜平面阻滞,根据罗哌卡因用量的不同分为3组,A组注入0.45%罗哌卡因20m L;B组注入0.35%罗哌卡因20 m L;C组注入0.25%罗哌卡因20 m L。用视觉模拟评分(VAS)及舒适度评分(BCS)评估患者术后3,6,12,24 h镇痛效应;比较3组患者第1次按压镇痛泵时间、24 h按压镇痛泵次数及舒芬太尼用量;记录3组患者术后相关药物不良反应发生情况。结果术后24 h,A、B、C组VAS分别为(1.81±0.24),(1.92±0.35),(2.75±0.64)分,BCS分别为(3.19±0.29),(3.11±0.23),(1.84±0.13)分,第1次按压镇痛泵时间分别为(13.14±1.02),(12.85±1.22),(7.24±0.79)h,24 h按压镇痛泵次数分别为(5.50±1.50),(5.20±1.80),(11.00±1.00)次,舒芬太尼用量分别为(61.25±1.98),(60.96±2.15),(71.21±2.18)m L,A、B组与C组比较,差异均有统计学意义(均P<0.05)。A、B、C组药物不良反应发生率分别为33.33%,14.29%,11.90%,与A组比较,差异有统计学意义(P<0.05)。结论0.35%罗哌卡因20 m L经腹横筋膜平面阻滞对进行剖宫产的产妇术后的镇痛效果更佳,可有效减少术后舒芬太尼用量及术后相关药物不良反应,且患者的舒适度更佳。

关键词：腹横肌平面阻滞罗哌卡因剖宫产术后舒芬太尼镇痛药物不良反应