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Structural evolution of Al–8%Si hypoeutectic alloy by ultrasonic processing

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journal of Materials Science & Technology 2017年第11期33卷 1235-1239页

作者： j.Y.Wang b.j.Wang L.F.Huang Department of Applied Physics Northwestern Polytechnical University Xi'an 710072 China

High intensity power ultrasound was respectively introduced into three different solidification stages of Al–8%Si hypoeutectic alloy, including the fully liquid state before nucleation, the nucleation and growth process of primary α（Al） phase and L →（Al）＋（Si） eutectic transformation period. It is found that both the primary α（Al） phase and（Al ＋ Si） eutectic structure were refined by different degrees with various growth morphologies depending on the ultrasonic treatment stage. based on the experimental results,the cavitation-induced nucleation due to the high undercooling caused by the collapse of tiny cavities was proposed as the major reason for refining the primary α（Al） phase. Meanwhile, obvious eutectic morphological change was observed only when ultrasound was directly introduced in the eutectic transformation stage, in which typical divorced eutectics and（Al ＋ Si） eutectic cells with symmetrical flower shape were formed at the top of the alloy sample. The introduction of ultrasound in each solidification stage also improves the yield strength of Al–8% Si alloy to a diverse extent.

关键词： Solidification Microstructure Metals and alloys Power ultrasound Refinement

Surface Characterization and Cell Response of binary Ti-Ag Alloys with CP Ti as Material Control

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journal of Materials Science & Technology 2012年第9期28卷 779-784页

作者： b.b. Zhang K.j. Qiu b.L. Wang L. Li Y.F. Zheng Center for biomedical Materials and Engineering Harbin Engineering University Harbin 150001 China Department of Materials Science and Engineering College of Engineering Peking University Beijing 100871 China

In this study, the surface passive films, dissolution behavior and biocompatibility of Ti-Ag alloys （with 5%, 10% and 20% Ag） were evaluated by X-ray diffraction （XRD） tests, electrochemical corrosion tests, X-ray photoelectron spectroscopy （XPS） tests, dissolution tests and in-vitro cytotoxicity tests. The surface films on the Ti-20Ag alloy are rich in Ti and much deficient in Ag with respect to alloy composition, as identified by XPS. Compared to CP Ti, Ti-SAg and Ti-20Ag alloys show larger impedances and lower capacitances, which can be associated with an increase of the passive layer thickness. Moreover, all Ti-Ag alloys exhibit negligible or low metal release in the test solutions. The in-vitro cytotoxicity results show Ti-Ag alloys seem to be as cytocompatible as CP Ti. From the viewpoint of surface passive film and cytotoxicity, Ti-SAg and Ti-20Ag are considered to be more suitable for dental applications.

关键词： Ti-Ag alloy Surfaces Electrochemical corrosion Cytotoxicity

Movement of tidal watersheds in the Wadden Sea and its consequences on the morphological development

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International journal of Sediment Research 2013年第2期28卷 162-171页

作者： Z.b.WANG j.VROOM b.C.van PROOIjEN R.j.LAbEUR M.j.F.STIVE Delft University of Technology Faculty of Civil Engineering and Geosciences

The Wadden Sea consists of a series of tidal lagoons which are connected to the North Sea by tidal *** of each lagoon are the mainland coast,the barrier islands on both sides of the tidal inlet,and the tidal watersheds behind the two barrier *** each Wadden Island there is a tidal watershed separating two adjacent tidal *** locations of the tidal watersheds in the Wadden Sea are not *** after a human interference in one of the tidal lagoons,a tidal watershed can move and thereby influence the distribution of area between the lagoons. This appears to be important for the morphological development in not only the basin in which the interference takes place,but also in the adjacent *** paper describes theoretical analyses and numerical modelling aimed at improving the insights into the location of the tidal watersheds,their movements,and the impact of the movements of tidal watersheds on the morphological development of a multi-basin system like the Wadden Sea.

关键词： Wadden Sea Tide Tidal watershed Morphological equilibrium Sediment demand

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基督教能对后现代世界做出贡献吗？

宗教 2002年第6期 33-39页

作者： j.b.科布

专栏主持人：曲跃厚〔主持人的话〕英国哲学家怀特海有句名言：“提出一种世界观，也就提出了一种宗教。”这句话也同样适合于当代美国著名后现代思想家j.b.科布(*** ***,1925-)。事实上，怀特海的哲学正是科布思想的源泉。科布的世界...

专栏主持人：曲跃厚〔主持人的话〕英国哲学家怀特海有句名言：“提出一种世界观，也就提出了一种宗教。”这句话也同样适合于当代美国著名后现代思想家j.b.科布(*** ***,1925-)。事实上，怀特海的哲学正是科布思想的源泉。科布的世界观是一种后现代的生态世界观，他的宗教神学是一种后现代的过程神学。科布的后现代思想以其建设性的旨归独树一帜，区别于解构性后现代主义的主流话语，为后现代思潮的研究吹来一股清新的风，在当今世界有着广泛的影响。

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梯度投影法及其发明过程

曲阜师范大学学报（自然科学版） 1992年第1期18卷 50-52页

作者： j.b.罗森美国明尼苏达大学计算机系

梯度投影法是应生产的需要,在最速下降法的基础上,借助于几何直观而产生的一种解决非线性规划问题的有效算法.

关键词：非线性规划梯度投影法负梯度几何意义

STUDY ON HIGH TEMPERATURE PERFORMANCES OF MCrAlX COATINGS DEPOSITED bY MULTI-ARC ION PLATING

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Acta Metallurgica Sinica(English Letters) 1999年第5期12卷 1019-1024页

作者： j. Zhang, j.b. Li, Q.Heng and X.H.Zhang Shenyang University,Shenyang 110044,China L.Q.Qi LiMing Aeroengine Manufacfruing Corperation, Shenyang 110043,China

NCoCrAlSiYHf and CoNiCrAlTaY coatings which belong to protective Al 2O 3 scale forming type were deposited by multi arc ion plating technique . The effect of deposition process parameters on qualities of the coatings was discussed. The high temperature oxidation performances isothermal oxidation with 950℃ / 500h and 1100℃ / 100h were studied. And also, the hot corrosion performances at 700℃ and 800℃, with molten mixed salt composed of 75%wt Na 2SO 4 and 25%wt NaCl were investigated. Then the high temperature protection decaying mechanisms were proposed.

关键词： multi arc ion plating superalloy coating isothermal oxidation hotcorrosion

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基督教能对后现代世界做出贡献吗？

新思路 2002年第6期 33-39页

作者： j.b.科布

一、基督教：进入后现代世界的源泉抑或障碍？基督教已经在西方世界丧失了其占统治地位的作用。在很多国家，基督教在政治上不再被确立为官方的和受到国家支持的宗教；而且，即使在那些仍存在着这种支持的地方，它也正在衰落。更重要的...

一、基督教：进入后现代世界的源泉抑或障碍？基督教已经在西方世界丧失了其占统治地位的作用。在很多国家，基督教在政治上不再被确立为官方的和受到国家支持的宗教；而且，即使在那些仍存在着这种支持的地方，它也正在衰落。更重要的是，基督教在大多数公民的信仰体系中已不再占主要地位，甚至大多数加入教会的人的基本态度和信念也是通过其它源泉而非基督教共同体及其传统而形成的。大多数世俗思想都把基督教当作后现代变革（甚至现代性）的一个障碍。基督教在多种宗教和文化传统（基于这些传统，必定会形成一种后现代的、世俗的或多元论的文化）中，被视为一种明达的(informing)宗教。由于基督教在过去一直占统治地位，大多数解构都是针对这一特定传统的解构。大量对这一传统承担了义务的辩护者的涌现，使得必需的解构困难重重。理解这一传统可能很重要，但许多现代主义者和后现代主义者也许未必都认识到，人们可能求助于它。然而，现实要复杂得多。某些基督徒以种种方式将其传统理解为进入后现代世界的一个积极的源泉。而且，这些理解方式不是从外部强加的，而是来自其内部的反思。基督教是步入一个后现代世界的障碍还是源泉，取决于其追随者如何理解其信仰的意义。它对一个基督徒意味着什么呢？大多数主要的答案都把基督教当作一种障碍，但另一种理解信仰的方式则把它当作了一个源泉。许多后现代主义者都熟悉对基督教的这种理解的论证，它拒斥了语言映照了一种客观和独立的实在的观点。只有语言才能通向一个“实在的”世界，因此语言不可能与那个世界相符。相反，我们栖居的世界是一个语言的世界。这表明，基督教教义不应被视为关于事物本身的各种断言，它们不应该在这个意义上来理解。相反，它们构造了一个能够规范理解和生活的符号和意义的系统。这样，基督教才能把自己理解为一个文化—语言系统。这种神学后现代主义具有这样的优点，它放弃了所有基督教的霸权主张，使其他人具有根据其选择的意义系统塑造其生活的平等权利。这当然是一种进步，由此而塑造的基督徒才可能关照他人及邻人，不把自己的意志和价值强加给他们，他们将为满足社会的某些需要做出积极的贡献。但是，尚不清楚的是，那些接受了这种理解的基督徒能否像基督徒那样有助于更广泛的社会中的政策的形成呢？如果能够的话，他们的活动似乎不像是基督徒，而像是某些具有其它认同的人。然而，人们承继的符号系统鼓励人们关怀作为一个整体的社会，而且，社会的利益不可能只靠个人而获得。

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电子计算机在油田生产管理上的应用

油气田地面工程 1972年第5期 43-46+48-56页

作者： j.b.科克斯

佩加苏斯电子计算机系统。是莫比尔石油公司操作的一个复杂的电子系统。该系统能自动地控制油井、收集有关的操作数据。检查状态和相应的控制作用。系统于1965年12月至1968年9月期间设计、编程序和安装的。

关键词：计算机计算机控制系统油田矿物燃料矿床气举井试井高压系统凝析油石油

Scale Effects of Geographical Soil Datasets on Soil Carbon Estimation in Louisiana,USA:A Comparison of STATSGO and SSURGO

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Pedosphere 2011年第4期21卷 491-501页

作者： b. ZHONG Y. j. XU School of Renewable Natural Resources Louisiana State University Agricultural Center Baton Rouge LA 70803 (USA)

Estimation of soil organic carbon （SOC） pools and fluxes bears large uncertainties because SOC stocks vary greatly over geographical space and through time. Although development of the U.S. Soil Survey Geographic Database （SSURGO）, currently the most detailed level with a map scale ranging from 1：12 000 to 1：63 360, has involved substantial government funds and coordinated network efforts, very few studies have utilized it for soil carbon assessment at the large landscape scale. The objectives of this study were to 1） compare estimates in soil organic matter among SSURGO, the State Soil Geographic Database （STATSGO）, and referenced field measurements at the soil map unit; 2） examine the influence of missing data on SOC estimation by SSURGO and STATSGO; 3） quantify spatial differences in SOC estimation between SSURGO and STATSCO, specifically for the state of Louisiana; and 4） assess scale effects on soil organic carbon density （SOCD） estimates from a soil map unit to a watershed and a river basin scale. SOC was estimated using soil attributes of SSURGO and STATSGO including soil organic matter （SOM） content, soil layer depth, and bulk density. Paired t-test, correlation, and regression analyses were performed to investigate various relations of SOC and SOM among the datasets. There were positive relations of SOC estimates between SSURGO and STATSGO at the soil map unit （R2 = 0.56, n = 86, t = 1.65, P = 0.102; depth： 30 cm）. However, the SOC estimated by STATSGO were 9%, 33% and 36~ lower for the upper 30-cm, the upper l-m, and the maximal depth （up to 2.75 m） soils, respectively, than those from SSURGO. The difference tended to increase as the spatial scale changes from the soil map unit to the watershed and river basin scales. Compared with the referenced field measurements, the estimates in SOM by SSURGO showed a closer match than those of STATSCO, indicating that the former was more accurate than the latter in SOC estimation, both in spatial and temporal resoluti

关键词： carbon accounting climate change GIS soil organic carbon soil organic matter