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71.
Tim MatthewsAuthor Vitae 《Computer Fraud & Security》2012,2012(5):18-20
72.
多年来,环境保护一直是烧结行业的一个重要课题.由于政府部门提出了更加严格的要求,烧结厂废气的进一步净化已经变得很有必要.一套新开发的、工业化的EFA(曳流吸收塔)烟气处理系统于2006年年中在ROGESA钢铁公司投入运行.本文就该系统的工艺流程、特点及运行情况作一介绍. 相似文献
73.
74.
Molecular Heterojunctions of Oligo(phenylene ethynylene)s with Linear to Cruciform Framework 下载免费PDF全文
Zhongming Wei Tim Hansen Marco Santella Xintai Wang Christian R. Parker Xingbin Jiang Tao Li Magni Glyvradal Karsten Jennum Emil Glibstrup Nicolas Bovet Xiaowei Wang Wenping Hu Gemma C. Solomon Mogens Brøndsted Nielsen Xiaohui Qiu Thomas Bjørnholm Kasper Nørgaard Bo W. Laursen 《Advanced functional materials》2015,25(11):1700-1708
Electrical transport properties of molecular junctions are fundamentally affected by the energy alignment between molecular frontier orbitals (highest occupied molecular orbital (HOMO) or lowest unoccupied molecular orbital (LUMO)) and Fermi level (or work function) of electrode metals. Dithiafulvene (DTF) is used as substituent group to the oligo(phenylene ethynylene) (OPE) molecular wires and different molecular structures based on OPE3 backbone (with linear to cruciform framework) are achieved, with viable molecular orbitals and HOMO–LUMO energy gaps. OPE3, OPE3–DTF, and OPE3–tetrathiafulvalene (TTF) can form good self‐assembled monolayers (SAMs) on Au substrates. Molecular heterojunctions based on these SAMs are investigated using conducting probe–atomic force microscopy with different tips (Ag, Au, and Pt) and Fermi levels. The calibrated conductance values follow the sequence OPE3–TTF > OPE3–DTF > OPE3 irrespective of the tip metal. Rectification properties (or diode behavior) are observed in case of the Ag tip for which the work function is furthest from the HOMO levels of the OPE3s. Quantum chemical calculations of the transmission qualitatively agree with the experimental data and reproduce the substituent effect of DTF. Zero‐bias conductance, and symmetric or asymmetric couplings to the electrodes are investigated. The results indicate that improved fidelity of molecular transport measurements may be achieved by systematic studies of homologues series of molecular wires applying several different metal electrodes. 相似文献
75.
This article explores the historical context, process and result of introducing and implementing ‘new’ town planning in early post‐war Taiwan. The two so‐called ‘garden cities’ are examined: Jhong‐Sing New Village and Yonghe City, both of which were formulated in the mid‐1950s by the same group of local planners. It reveals that the assumed necessity of importing Western planning paradigms arose from the abrupt escalation of urban concentration caused by the late 1940s mass migrations from China. To cope with this unprecedented population growth, planning profession was swiftly established. The novice planners, in search of a reference for developing ‘new’ towns to decentralise excessive urbanisation, modelled their ‘new’ town planning on English suburban morphology. In the absence of an input of external expertise, the planners appeared to mistake aesthetic order and pastoral imagery of low‐density residential development in England as practically viable solutions to the pressing urban problems in Taiwan. In a false hope that adopting Western ideas and practices would quickly lead the island to a better world, Taiwan initiated the importation of planning paradigms. This planning transfer not only evidently manifests a mode of ‘borrowing’ in post‐colonial countries in international diffusion but also re‐articulates the disseminating nature of modern planning and the existence of one‐direction flows characterising the global dynamics of diffusion in the twentieth century. 相似文献
76.
Tim Knudsen 《Planning Perspectives》2013,28(3):297-310
Influences on early Danish planning came from a variety of international sources. The Big City paradigm was mainly taken over from German planning, sometimes varied with elements from Haussmann and American cities. Later inspiration from Camillo Sitte and from the English Garden City movement was combined with traditional Danish small town values into a competing paradigm. The engineers mainly adhered to the Big City paradigm, whilst the architects were the chief proponents of the English inspiration, and these two paradigms have been used as tools of rivalry between the two professions. This discord might in the long run have led to a weakening of the planners’ political influence. 相似文献
77.
The numbers of English public houses or “pubs” have reduced significantly in the last two decades. Politicians have called on the planning system to resist their closure but, at the same time, demand further controls over high-street bars. This paper explores the reasons for the decline and the rationale for supporting the continuation of the “traditional” English pub. Using evidence drawn from a wider study of the relationships between places and youth drinking cultures, the paper discusses young adults' use of pubs. While recognising the adverse effects of heavy drinking, arguments are put forward in support of the traditional pub as a site for restrained and responsible social interaction for young adults. The paper discusses the issues this raises for the UK planning system in the context of responsibilities for social sustainability and public health. 相似文献
78.
Synthesis and Crystal Structure Characterization of Oxysilicate Apatites for Stabilization of Sr and Rare‐Earth Elements 下载免费PDF全文
Jingxian Wang Fengxia Wei Soo Min Lim Erjia Liu Claude Guet Tim White ZhiLi Dong 《Journal of the American Ceramic Society》2016,99(5):1761-1768
Strontium (Sr) containing rare‐earth oxysilicate apatite AI4AII6(SiO4)6O2 is considered a good matrix to accommodate radionuclide as its cation sites can incorporate lanthanide elements other than Sr. Here, we report a study on the synthesis of Nd8Sr2(SiO4)6O2 and Yb8Sr2(SiO4)6O2, which adopt P63/m apatite symmetry, as well as the characterization of crystallographic structures using X‐ray diffraction and electron microscopy. It is found that AI position is shared by Nd, Yb and Sr, and AIO6 polyhedra are face‐connected, forming column structures, which are linked to SiO4 tetrahedra, creating continuous channels. The Rietveld refinement shows that Nd and Yb prefer the AII position in the channel. The twisted angle of adjacent triangle faces in an AI‐O polyhedron along [001] is a critical parameter to identify the channel volume and its value varies when different cations are incorporated. The twisted angles for Nd‐apatite and Yb are 24.2° and 22.7° The findings provide a new insight into nuclear waste stabilization by apatite‐type structure. 相似文献
79.
Weakly lignified biomass, like brewers' spent grain and grass silage, is good feedstock for biorefineries. The biomass can be separated and converted into valuable products in different ways. In this study, brewers' spent grain is used to investigate solid state fermentations with Cellulomonas uda. Additionally, hydrothermal pretreatment and subsequent enzymatic saccharification, as well as formation of inhibitory compounds, is demonstrated. Hydrothermal pretreatment combined with simultaneous saccharification and fermentation is shown as an example for the utilization of grass silage. 相似文献
80.
One major problem that arises in the design of plastic parts, especially those that are fiber reinforced, is the change of shape and dimension as a result of shrinkage and warpage. These material inhomogeneities are caused by flowinduced fiber orientation, curing, poor thermal mold lay-out, and other processing conditions. This paper presents a simulation that predicts shirnkage and warpage of 3-D compression molded fiber reinforced composite parts. The simulation represents the structure with the 3-noded shell elements used in mold filling simulations. The calculated results indicate that fiber orientation strongly affect the final properties, which vary with different chage locations, have a significant effect on warpage. Unsymmetric curing, caused by uneven mold temperatures, could lead to a thermal moment that could possibly help reduce warpage. 相似文献