Microstructures and mechanical properties of as-cast Mg-5Y-3Nd-Zr-xGd (x=0, 2 and 4 wt.%) alloys

Mg-5Y-3Nd-0.6Zr-xGd (x = 0, 2 and 4 wt.%) alloys were prepared by metal mould casting technique, the structures and mechanical properties were investigated. The alloys were mainly composed of alpha-Mg solid solution and beta-phase. With increasing Gd content, Mg5RE phase increased and the grain was refined. The Mg-5Y-3Nd-2Gd-0.6Zr alloy exhibited highest ultimate tensile strength and Mg-5Y-3Nd-0.6Zr alloy showed highest yield strength at room temperature. With increasing amount of Gd, the thermal resistance was improved. The Mg-5Y-3Nd-4Gd-0.6Zr alloy exhibited highest UTS and YS at 250 degrees C, they were about 1.27 times higher than those of Gd-free alloy, which was mainly attributed to the increase of the beta-phase and Mg5RE strengthening phase.

A polymorph of diaquabis(pyrazine-2-carboxylato-kappa N-2(1),O)copper(II)

The title compound, [Cu(C5H3N2O2)(2)(H2O)(2)], is a new polymorph of the previously reported compound [Klein et al. (1982). Inorg. Chem. 21, 1891-1897]. The Cu-II atom, lying on an inversion center, is coordinated by two N atoms and two O atoms from two pyrazine-2-carboxylate ligands and by two water molecules in a distorted octahedral geometry with the water molecules occupying the axial sites. Intermolecular O-H center dot center dot center dot O, O-H center dot center dot center dot N and C-H center dot center dot center dot O hydrogen bonds connect the complex molecules into a two-dimensional layer parallel to (10 (1) over bar), whereas the previously reported polymorph exhibits a three-dimensional hydrogen-bonded network.

Bromophenols coupled with derivatives of amino acids and nucleosides from the red alga Rhodomela confervoides

Three new bromophenols coupled with pyroglutamic acid derivatives and one bromophenol coupled with deoxyguanosine were obtained from the red alga Rhodomela confervoides. By spectroscopic methods including 2D NMR and single-crystal X-ray structure analysis their structures were elucidated as N-(2,3-dibromo-4,5-dihydroxybenzyl)methyl pyroglutamate (1), N-(2,3-dibromo-4,5-dihydroxybenzyl)pyroglutamic acid (2), N-[3-bromo-2-(2,3-dibromo-4,5-dihydroxybenzyl)-4,5-dihydroxybenzyllmethyl pyroglutamate (3), and 2-N-(2,3-dibromo-4,5-dihydroxybenzylamino)deoxyguanosine (4), respectively. Compounds 1-4 were evaluated against several microorganisms and human cancer cell lines, but found inactive. To our knowledge this is the first report of bromophenols coupled with amino acid or nucleoside derivatives through the C-N bond.

滑动控制理论在海洋机器人动态定位系统中的应用

本文论述了一种新的鲁棒性控制方法——滑动控制理论.并将该方法应用于海洋机器人的动态定位系统设计.仿真结果表明该方法是相当成功和有效的,对系统的参数变化有强鲁棒性.

喀斯特森林群落退化对浅层岩溶地下水化学的影响

对贵州中部喀斯特地区植被调查及径流和岩溶水样分析,探讨喀斯特森林群落退化过程中浅层岩溶地下水化学组成的变化。结果表明:喀斯特森林生态系统降雨中离子浓度大小的排序为SO2 -4 > K+ 、Ca2 + 、HCO-3 >Na + 、Mg2 + 、Cl - > NO-3 、NH+4 > PO3 -4 ,而径流中离子浓度的大小排序为HCO-3 > SO2 -4 Ca2 + > Mg2 + 、Cl - > K+ 、Na + 、NO-3 > NH+4 > PO3 -4 ;岩溶地下水离子组成与径流总体相似,但岩溶地下中HCO-3 、Ca2 + 和Mg2 + 的含量及电导率明显增加高于地表径流。随着喀斯特森林群落从阔叶林群落向灌木林群落、灌草群落方向演替,其岩溶地下水中HCO-3 和Ca2 + 比例明显减少,而SO2 -4 比例明显增加。岩溶地下水的HCO-3 、Ca2 + 含量与森林覆盖率之间存在显著的正相关,而K+ 、NH+4 含量与森林覆盖率之间则存在显著的负相关。HCO-3 含量是影响岩溶地下水电导率的最重要因子,其次是Ca2 + ,再次是K+ 、Mg2 + ;岩溶地下水电导率可以作为评价喀斯特森林群落退化对生态环境影响的数量指标。

C 228 INST-D 2013. 390 Juguetes y productos decorativos elaborados en madera tallada y torneada.

14 fotografías, trece a color.

An heroic bishop : the life-story of French of Lahore

http://www.archive.org/details/anheroicbishopli00stocuoft

The pastor's missionary manual.

Boston University Theology Library

The Encyclopaedia of missions : descriptive, historical, biographical, statistical : with a full assortment of maps, a complete bibliography, and lists of Bible versions, missionary societies, mission stations, and a general index / edited by Edwin Munsell Bliss.

http://www.archive.org/details/encyclopaediamis02unknuoft

Lectures on the Tinnevelly missions, descriptive of the field, the work, and the results : with an introductory lecture on the progress of Christianity in India.

http://www.archive.org/details/lecturesontinnev00calduoft

The divine enterprise of missions a series of lectures

http://www.archive.org/details/divineenterprise00pieruoft

William F. Albright Papers

This file contains a finding aid for the William F. Albright Collection. To access the collection, please contact the archivist (asorarch@bu.edu) at the American Schools of Oriental Research, located at Boston University.

Towards Formalizing Java's Weak References

Weak references provide the programmer with limited control over the process of memory management. By using them, a programmer can make decisions based on previous actions that are taken by the garbage collector. Although this is often helpful, the outcome of a program using weak references is less predictable due to the nondeterminism they introduce in program evaluation. It is therefore desirable to have a framework of formal tools to reason about weak references and programs that use them. We present several calculi that formalize various aspects of weak references, inspired by their implementation in Java. We provide a calculus to model multiple levels of non-strong references, where a different garbage collection policy is applied to each level. We consider different collection policies such as eager collection and lazy collection. Similar to the way they are implemented in Java, we give the semantics of eager collection to weak references and the semantics of lazy collection to soft references. Moreover, we condition garbage collection on the availability of time and space resources. While time constraints are used in order to restrict garbage collection, space constraints are used in order to trigger it. Finalizers are a problematic feature in Java, especially when they interact with weak references. We provide a calculus to model finalizer evaluation. Since finalizers have little meaning in a language without side-effect, we introduce a limited form of side effect into the calculus. We discuss determinism and the separate notion of uniqueness of (evaluation) outcome. We show that in our calculus, finalizer evaluation does not affect uniqueness of outcome.

Journeying to a journal

At a Council meeting of the newly-formed Cork Historical and Archaeological Society, 17 November 1891, the Chairman /President, Revd R.A. Canon Sheehan, 'informed the meeting that Mr. Robert Day had been generous enough to place his valuable edition of Smith's History, with notes by Dr. Caulfield and Crofton Croker, at the disposal of the Society for publication'. At a subsequent meeting Wm Ringrose Atkins expressed the Society's thanks to W.A. Copinger 'who has kindly consented to edit Smith's Cork with Mr. Robert Day'. Thus began the work of rounding out close to two and a half centuries of antiquarian endeavour in Cork and of using its synthesis as a foundation for a new medium to record and communicate the social and cultural heritage of Cork city and county.

Politically motivated former prisoner groups: community activism and conflict transformation

Aims and objectives: This study represents the first sustained quantitative and qualitative attempt to involve both Republicans and Loyalists in an investigation of the impact of imprisonment and the role of politically motivated former prisoners in the process of conflict transformation in Northern Ireland. The overall aim of the project is to examine the ways in which groups of former prisoners are involved in peace-building and conflict transformation work and to evaluate the constraints and impediments placed upon their activities by the effects of the imprisonment process, politically motivated release and residual criminalisation. In pursuing the evaluation of the role of politically motivated former prisoners working within and without their own communities, the research has six specific objectives: To trace the evolution and development of former prisoner groups; To evaluate the impacts of imprisonment and release on the personal lives of former prisoners; To assess the constraints imposed on former prisoners as agents of change by the residual criminalisation arising from their status; To determine the potential of the former prisoner community in challenging intra-community tensions and evaluate their potential and actual contribution to conflict transformation at the inter-community level; To compare and contrast the effectiveness of Loyalist and Republican former prisoners as agents of change within their own communities; To explore the notion of former prisoners as agents of social and communal transformation within broader political processes through grounding the knowledge and practical experience of the former prisoner community within the broader conceptual context of conflict transformation.