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11.
Landscape design is an expression and repository of cultural values and beliefs, and in Aotearoa, New Zealand, the designed landscape faces particular challenges. Globalization is seen as a potential threat to landscape identity, which is even more significant for a country which has built its economy and self-image from its unique natural landscape. The potential for resistance is limited by the small size and youth of the profession of landscape architecture in New Zealand. While traditions of farming and gardening extend back to early European settlement in the mid nineteenth century, and beyond to indigenous Maori practices of land modification, professional landscape design is a relatively recent development (the first tertiary course in landscape architecture began at Lincoln College (now Lincoln University) in 1969). Landscape design in New Zealand draws its vocabulary from the power of the country's natural heritage landscapes, convinced that a naturalistic aesthetic exclusively represents environmental health. Some of the core values of New Zealand society are, however, overlooked by designers. The need to develop a critically informed design language which includes the farming landscape along with the natural one is argued. The invention of such a language, referred to as a complex ecological aesthetic, is seen as a potential source of design expression that is invigorated by the tension between mechanistic and natural landscape aesthetics. It therefore has the potential to promote environmental health, while being regionally grounded, and can help face the challenges that globilization poses to the landscape. 相似文献
12.
Jianzhao Liu Jacky W. Y. Lam Ben Zhong Tang 《Journal of Inorganic and Organometallic Polymers and Materials》2009,19(3):249-285
Aggregation generally quenches the light emissions of chromophoric molecules. In this review, we demonstrate that 1,1-disubstituted
2,3,4,5-tetraphenyl siloles and 2,5-difunctionalized siloles as well as their polymers exhibit the opposite behaviors. Instead
of quenching, aggregation has greatly boosted their photoluminescence quantum yields by up to two orders of magnitude, turning
them from faint fluorophores into strong emitters. Such “abnormal” phenomenon of “aggregation-induced emission (AIE)” is attributed
to restricted intramolecular rotations of the peripheral phenyl rings against the central silole core, which block the nonradiative
channel via the rotational energy relaxation processes and effectively populate the radiative decay of the excitons. Utilizing
such a novel effect, siloles and their polymers find an array of applications as: sensors for chemicals, explosives, pH, and
biomacromolecules (proteins, DNAs and RNAs), indicators for determining CMC and monitoring layer-by-layer self-assembling,
biocompatible fluorogens for cell imaging, visualizing agent for DNA gel electrophoresis, biolabels for immunoassay, stimuli-responsive
organic nanomaterials, magnetic fluorescent nanoparticles for potential bio-imaging and -separation, and outstanding materials
for efficient OLEDs and PV cells.
相似文献
Ben Zhong TangEmail: |
13.
Jianzhao Liu Jacky W. Y. Lam Matthias Häußler Anjun Qin Ben Zhong Tang 《Journal of Inorganic and Organometallic Polymers and Materials》2009,19(2):133-138
A group of hyperbranched poly(silylenearylene)s are synthesized by homopolycyclotrimerizations of A2-type silylenediynes. The polymers can be readily metallized by complexations of their periphery triple bonds with cobalt
octacarbonyls Co2(CO)8. Pyrolysis of these organometallic polymers gives magnetic ceramics in good yields. Analyses by SEM, TEM, XPS, EDX, and XRD
demonstrate that the ceramics comprise ferromagnetic Co and paramagnetic Co2Si nanocrystallites wrapped by carboneous shell. The ceramics show high magnetic susceptibilities (M
s up to ~50 emu/g) and near-zero coercivity (H
c down to ~0.14 kOe), suggesting that they are good soft magnetic materials with low hysteresis loss.
This article was to be included in the March issue of Volume 19, which was dedicated to Professor Takakazu Yamamoto. The journal
editors sincerely apologize for the omission and delay in publication for which the authors and the guest editor bare no responsibility.
M. Zeldin and A. S. Abd-El-Aziz, Editors. 相似文献
14.
Nathalie Dupuy Oswin Galtier Yveline Le Drau Christian Pinatel Jacky Kister Jacques Artaud 《European Journal of Lipid Science and Technology》2010,112(4):463-475
Chemometric treatment of near‐infrared (NIR) and mid‐infrared (MIR) combined spectra was used firstly to predict oil and water contents in fresh olive fruit samples (n = 223) and secondly to classify these samples into five principal French cultivar origins (Aglandau, Cailletier, Olivière, Salonenque, and Tanche). The study was carried out during four crop years (2005/2006 to 2008/2009) to take into account the seasonal variations. The comparison of the results obtained in the combined range (REP = 2.6% for the water content and 3.5% for the oil content) provides an obvious advantage compared to the NIR and MIR techniques used separately. Fresh olive fruit cultivars were satisfactorily classified with the partial least squares‐discriminant analysis (PLS‐DA) method in the combined range. After use of the K‐means clustering on the PLS‐DA scores, all the samples were well classified into their five groups of origin. The use of infrared combined spectra allows a considerable improvement in estimating olive fruit quality (oil and water contents, varietal origins). 相似文献
15.
16.
Neville K. S. Lee Jacky K. H. Chow Albert C. K. Chan 《The International Journal of Advanced Manufacturing Technology》2009,44(5-6):539-547
For most of the high-speed hole diameter measuring process, a contact measuring method is undesirable due to its slow and destructive touching process. Thus, an optical method is usually chosen for non-contact measurement. Unfortunately, for most holes in precise manufacturing, especially those with a high aspect ratio, the optical method cannot be used. In our study, we developed a simple and low-cost precision capacitive hole measuring system. By using a simple alignment mechanism, we prove that a high-resolution hole diameter can be achieved. Comparing a traditional measuring method like coordinate measuring machine with our system, over 99% correlation is easily obtained. The paper also presents a multilayer hole measuring probe and sensor probe for non-through-hole measurement. 相似文献
17.
This work investigated the resuspension and subsequent translocation of particulate matter (PM) from carpeted flooring surfaces due to walking. In addition, the effect of HVAC systems and ceiling fans on mixing and/or translocation of resuspended PM was studied. Testing took place both in a residence with a well-worn, soiled carpet and in an environmental test chamber. Prescribed walking occurred with PM measurements taken at multiple sampling heights. Scanning electron microscopy (SEM) of carpet fibers was used to determine the fraction of dust available for resuspension. These data, in conjunction with resuspended mass concentrations from this study, were used to generate emission factors by particle size for walking on both new and worn carpet. Carpet loading does not affect the emission factor, indicating that the amount of resuspended PM is directly proportional to the available PM in the carpet. While relative humidity (RH) plays an important role in resuspension from new carpets, with high RH enhancing resuspension, it has the opposite affect with old carpets, with increased RH decreasing resuspension. With the HVAC system on, translocated particles 1.2 m horizontally from the source had number concentrations of approximately 20–40% of those at the source. With a ceiling fan on, extensive mixing was noted with little difference seen in particle resuspension by height. With the ceiling fan off, there was very little mixing present and particle size varied substantially by height. 相似文献
18.
Identifying the critical success factors for relationship management in PPP projects 总被引:1,自引:0,他引:1
Weiwu Zou Mohan Kumaraswamy Jacky Chung James Wong 《International Journal of Project Management》2014
The longer the contract period, the higher the chance that major changes will arise. Thus a greater reliance on the established relationships is needed to maintain the contractual bond in PPP project. Relationship management (RM) can therefore be expected to be even more valuable in the PPP context. This paper aims to investigate current perceptions and experiences of RM in PPP projects and more importantly, to identify the CSFs for RM in PPP projects. By means of an empirical questionnaire survey geared towards PPP practitioners with direct hands-on experience, the opinions were solicited, analyzed and compared in relation to potential PPP RM success factors. The survey findings indicate that industry practitioners currently lack a general understanding of concepts and applications of RM, given that it is relatively new in PPP. However, they do think that RM is very important to improve the present performance of PPPs. Future PPP business opportunities can also be increased by effective RM. The top four CSFs for RM are found to be commitment of senior executives, defining the objectives, integration of the different divisions and a multidisciplinary team. However, the relative importance presently assigned for each of the above factors is insufficient, and commitment from senior management is perceived as the most difficult factor to improve. 相似文献
19.
The poly(C60-co-styrene)s prepared by radical copolymerizations of C60 and styrene in bulk were characterized by multiple-detector size-exclusion chromatographs consisting of a refractometer, a differential viscometer, and/or a right-angle laser-light scattering photometer. The multidetector systems enabled the determinations of reliable, absolute molecular weights of the copolymers. The plots of intrinsic viscosity vs. molecular weight and radius of gyration vs. molecular weight offered valuable information about the molecular architectures of the copolymers. The slopes of the plots reveal that the structure of the copolymer changes with its C60 content: the copolymer with a low C60 content of 0.58 wt% possesses a linear structure, whereas its conger with a high C60 content of 1.14 wt% possesses a branched structure. 相似文献
20.
In this paper the role of microstructure and residual stresses on fatigue crack initiation of gaseous carbonitrided steels is examined. Optimum for austenite content in the case is investigated for microstructures containing bainite and for those without bainite. Fractographic study suggests subsurface initiation sites for notched specimens when austenite content is high and initiation sites at the surface when austenite is low. 相似文献