Single-crystal growth of the complex metallic alloy phase β-Al–Mg

The development of a single-crystal growth route for the complex metallic alloy phase β-Al₃Mg₂ is presented. After initial probing of the phase diagram in the vicinity of the existence range of the β-phase, we performed single-crystal growth experiments employing various techniques. The Czochralski and self-flux growth turned out to be the most suitable for this phase, and with both we reproducibly achieved single crystals of several cubic centimeters in volume. While the Czochralski technique allows for the production of deliberately oriented single crystals, the self-flux technique is capable of producing very large but unoriented single grains.     

杂粮粉对混粉特性及蛋糕品质的影响

以复配的杂粮粉为主要原料研究杂粮蛋糕的配方,通过单因素及正交试验,考察杂粮粉、蛋糕油、鸡蛋、糖的添加量对杂粮蛋糕感官品质及面粉粉质和面团拉伸特性的影响。优化杂粮蛋糕配方,确定其最佳配方为:小麦粉80%、杂粮粉添加量20%、鸡蛋200%、糖80%、蛋糕油10%、色拉油20%、牛奶20%(以总粉计)。在此配比下制作出的蛋糕蛋香纯正、组织细密,口感好。     

On the peritectoid formation of Ni5Al3

The peritectoid formation of Ni₅Al₃ from the two phases NiAl and Ni₃Al was studied in a Ni---Al alloy containing 66 at% Ni by means of transmission electron microscopy. The product phase does not form as a uniform layer between the two initial phases as expected and already observed in a few systems. In the system studied here there are only very few nucleation sites located at the NiAl/Ni₃Al interface. The further growth of Ni₅Al₃ takes place only into one of the initial phases which is NiAl. A strict orientation relationship between NiAl and Ni₅Al₃ was observed; the growth direction was [221]. The transformation is presumably diffusion controlled; it is very sluggish and it can be described by a nucleation and growth process. From the study presented here we conclude that the formation of Ni₅Al₃ proceeds by a micromechanism which differs from that normally assumed for peritectoid reactions.     

土钉注浆技术在杂填土基坑中的应用

采用花管打入式成孔与高压注浆相结合的土钉墙施工工艺,成功处理了长春银座B座杂填土基坑,并将现场土钉抗拔试验与数值模拟相比较,结合现场的监测数据,认为达到了较好的支护效果。     

Point defects and diffusion in ordered alloys: An ab initio study of the effect of vibrations

We present a detailed investigation of the influence of atomic vibrations on the point defect and diffusion properties of ordered metallic alloys, by means of ab initio calculations with density-functional theory. Considering the case of Ni₂Al₃ which provides a rich panel of defect-related properties, our study reveals that the behaviour of this compound is largely monitored by self-interstitials, whereas such defects are usually ignored in metallic compounds. The vibration free energies are obtained for the full set of point defects of Ni₂Al₃, showing that these quantities are strongly defect-dependent, and significantly modify the free energy of the compound in an intricate composition-dependent manner. The second key-issue is the first ab initio full analysis of attempt frequencies, via the coupling of vibration analysis and saddle-point search for significant atomic jumps. This analysis indicates that attempt frequencies range over several orders of magnitude and exponentially increase with migration energies. We show the importance of these factors in reaching realistic composition-dependent diffusion coefficients.     

一物一事总关情——“二拍”和明中后叶杂剧僧道题材创作尚俗倾向浅析

明代中后期是一个思想解放的混乱时期,话本小说与杂剧在创作题材的选择方面,生活化和世俗化的倾向愈加明显,即都积极地捕捉生活当中的兴奋点加以表现,展现世俗生活,关注百姓日用。作品的现实性得以大大加强,使之成为社会的一面镜子,美丑尽在其中。     

Effect of ball milling on structure and thermal stability of Al84Gd6Ni7Co3 glassy powders

The influence of ball milling on microstructure and thermal stability of the gas-atomized Al₈₄Gd₆Ni₇Co₃ glassy powder has been investigated as a function of the milling time. The results show that the traces of crystalline phases present in the as-atomized powder decrease gradually with increasing the milling time. The thermal stability of the fcc-Al primary phase increases while the thermal stability of the intermetallic phases decreases with increasing milling. Moreover, significant improvement in hardness occurs after milling, which is attributed to the amorphization of the residual crystalline phases present in the as-atomized powder. These results demonstrate that milling is an effective way for amorphizing the residual crystalline present in the amorphous matrix and to control the thermal stability of the material.     

Network Quality Assessment in Heterogeneous Wireless Settings: An Optimization Approach

The identification of an effective network which can efficiently meet the service requirements of the target, while maintaining ultimate performance at an increased level is significant and challenging in a fully interconnected wireless medium. The wrong selection can contribute to unwanted situations like frustrated users, slow service, traffic congestion issues, missed and/or interrupted calls, and wastefulness of precious network components. Conventional schemes estimate the handoff need and cause the network screening process by a single metric. The strategies are not effective enough because traffic characteristics, user expectations, network terminology and other essential device metrics are not taken into account. This article describes an intelligent computing technique based on Multiple-Criteria Decision-Making (MCDM) approach developed based on integrated Fuzzy AHP-TOPSIS which ensures flexible usability and maximizes the experience of end-users in miscellaneous wireless settings. In different components the handover need is assessed and the desired network is chosen. Further, fuzzy sets provide effective solutions to address decision making problems where experts counter uncertainty to make a decision. The proposed research endeavor will support designers and developers to identify, select and prioritize best attributes for ensuring flexible usability in miscellaneous wireless settings. The results of this research endeavor depict that this proposed computational procedure would be the most conversant mechanism for determining the usability and experience of end-users.     

Standardised building in housing construction and economical construction methods

Building prices and construction costs for housing construction in Germany are growing dynamically. The main cost drivers are still legal, normative and other regulations that are generally drawn up at federal level. However, the trend in building prices also shows that intense building activity is also affecting prices. This trend is also complex: the trend in the groups of trades concerned with carcass work can be categorised between the rate of inflation and increased building prices. The price trend in the whole of technical completion, on the other hand, is disproportionate, and it is these completion trades (heating, ventilation, sanitation and electrical) that are actually driving construction costs. Building materials for primary construction of our residential buildings are also developing at different rates. Masonry falls within the sphere of the general growth rate of prices, while reinforced concrete and wood are much higher. This overall trend shows the finiteness of supposedly simple solutions for accelerating the rate of construction in housing construction. Serial building can only offer a niche solution. Far more intelligent is the use of standardised construction, i.e. repetition of ideal ground plans, development types and standardised buildings that can be adapted to the conditions at each site. Furthermore, it is clear that the use of masonry construction in a multi‐floor residential building is still the most economical type of building to construct in Germany.     

Thermodynamic assessment on the Pb–Ca–Sn ternary system

Thermodynamic modelling of the Pb–Ca–Sn ternary system was carried out with the help of the CALculation of PHase Diagrams (CALPHAD) method.The binary borders related to the ternary system were investigated. The lead–tin system is already calculated, the calcium–tin and calcium–lead systems can be described with the association model in binary liquid. The establishment of the modelling of the Pb–Ca–Sn phase diagram was done after collecting own experimental information. The introduction of new interaction parameters related to the ternary liquid, leads to an accurate restoration of the experimental data.Calculated isothermal, isoplethal sections and liquidus surfaces are presented. They confirm that the calcium solubility in lead matrix drastically decreases with the introduction of tin as well as with the decreasing of temperature. The industrial process applied to the lead–calcium–tin alloys finds some justifications in the calculated phase diagram.