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101.
Self-concept development in the toddler years. 总被引:1,自引:0,他引:1
102.
Zsuzsa Banhalmi-Zakar Claire Gronow Lachlan Wilkinson Bryan Jenkins Jenny Pope Geraldine Squires 《影响评估与项目评价》2018,36(6):506-515
Impact assessment (IA) has become one of the most prevalent environmental policy instruments today. Its introduction under the National Environmental Policy Act (US) in 1969 was revolutionary. Perhaps it is not surprising, then, that such a widely used tool has received its share of criticism, including that it fails to meet some of its fundamental goals. Over the last fifty years, IA has broadened in scope and application and embraced new techniques. It has followed evolved, but has not changed fundamentally.We believe that IA must continue to change to meet the societal and environmental challenges of the 21st century. But will it be enough for IA to progress through incremental change (evolution), or is a complete overhaul of impact assessment (revolution) needed? We provide some ideas as to what ‘evolution’ and ‘revolution’ may look like, but rather then offering a definitive way forward now, we invite stakeholders to present their thoughts and suggestions at the IAIA19 Annual Conference in Brisbane, which carries the same theme as the title of this article. 相似文献
103.
104.
Lianfeng Zhao Kwangdong Roh Sara Kacmoli Khaled Al Kurdi Samik Jhulki Stephen Barlow Seth R. Marder Claire Gmachl Barry P. Rand 《Advanced materials (Deerfield Beach, Fla.)》2020,32(25):2000752
The performance of lead-halide perovskite light-emitting diodes (LEDs) has increased rapidly in recent years. However, most reports feature devices operated at relatively small current densities (<500 mA cm−2) with moderate radiance (<400 W sr−1 m−2). Here, Joule heating and inefficient thermal dissipation are shown to be major obstacles toward high radiance and long lifetime. Several thermal management strategies are proposed in this work, such as doping charge-transport layers, optimizing device geometry, and attaching heat spreaders and sinks. Combining these strategies, high-performance perovskite LEDs are demonstrated with maximum radiance of 2555 W sr−1 m−2, peak external quantum efficiency (EQE) of 17%, considerably reduced EQE roll-off (EQE > 10% to current densities as high as 2000 mA cm−2), and tenfold increase in operational lifetime (when driven at 100 mA cm−2). Furthermore, with proper thermal management, a maximum current density of 2.5 kA cm−2 and an EQE of ≈1% at 1 kA cm−2 are shown using electrical pulses, which represents an important milestone toward electrically driven perovskite lasers. 相似文献
105.
Azad Rasul Heiko Balzter Claire Smith 《International journal of remote sensing》2017,38(13):3960-3980
The difference between surface and air temperature within a city and its surrounding area is a result of variations in surface cover, thermal capacity, and 3-dimensional geometry. This research has examined and quantified the decreasing daytime land surface temperature (LST) in Erbil, Kurdistan region of Iraq, and the influence of rapid urban expansion on urban heat/cool island effect over a 20 year period. Land-use/land-cover change across this time period is also established using pixel samples. The current study proposes the application of the normalized ratio scale (NRS) to adjust the temperature of images acquired at different dates to the same range. Eleven satellite images acquired by Landsat 4, 5, 7, and 8 during the period 1992–2013 are used to retrieve LST. The results indicate that 55.3 km2 of city land cover changed from bare soil to urban; consequently, the mean LST of the new urbanized area decreased by 2.28°C. The normalized difference vegetation index (NDVI) of Sami Abdul-Rahman (S.A.) Park increased from 0.09 ± 0.01 to 0.32 ± 0.11, resulting in a decrease of the mean LST by 7.29°C. This study shows that the NRS method is appropriate for detecting temperature trends from urbanization using remote-sensing data. It also highlights that urban expansion may lead to a decrease in daytime LST in drylands. 相似文献
106.
Hemant J. Desai Daniel O. Acheampong Robert Hudson Richard Lacey Claire Stanley Helen Turner 《Journal of Energetic Materials》2017,35(1):109-124
The synthesis of a novel heterocyclic–telechelic polymer, α,ω-oxetanyl-telechelic poly(3-nitratomethyl-3-methyl oxetane), is described. Infrared spectroscopy (IR), gel permeation chromatography (GPC), and nuclear magnetic resonance (NMR) spectroscopy have been used to confirm the successful synthesis, demonstrating the presence of the telechelic-oxetanyl moieties. Synthesis of the terminal functionalities has been achieved via displacement of nitrato groups, in a manner similar to that employed with other leaving groups such as azido, bromo, and nitro, initiated by nucleophiles. In the present case, displacement occurs on the ends of a nitrato-functionalized polymer driven by the formation of sodium nitrate, which is supported by the polar aprotic solvent N,N-dimethyl formamide. The formation of an alkoxide at the polymer chain ends is favored and allows internal back-biting to the nearest carbon bearing the nitrato group, intrinsically in an SN2(i) reaction, leading to α,ω-oxetanyl functionalization. The telechelic-oxetanyl moieties have the potential to be cross-linked by chemical (e.g., acidic) or radiative (e.g., ultraviolet) curing methods without the use of high temperatures, usually below 100°C. This type of material was designed for future use as a contraband simulant, whereby it would form the predominant constituent of elastomeric composites comprising rubbery polymer with small quantities of solids, typically crystals of contraband substances, such as explosives or narcotics. This method also provides an alternative approach to ring closure and synthesis of heterocycles. 相似文献
107.
Claire M. Côte Chris J. Moran Christopher J. Hedemann 《Mine Water and the Environment》2007,26(4):229-236
Unprecedented expansion of coal mining in Australia is occurring within the context of a severe ongoing drought. This has
induced more companies to adopt improved water management strategies, such as water reuse. A direct consequence of this is
an increase in the salt concentration of the water, which affects in turn the efficiency of the coal preparation processes,
the quality of the coal product, and the level of required equipment maintenance. There are three strategies that can be adopted
with respect to salt management: accept the elevated salt concentrations and increase spending on equipment maintenance; remove
the salt by desalination; and dilute the salt by importing more water. A tool is required to predict the salt concentrations
arising from water reuse and to simulate the impact of potential management strategies. This paper presents a systems approach
to the modelling of coupled mine site water and salt balances to assist with understanding the implications of implementing
desalination or dilution and with assessing the costs and benefits of each option. 相似文献
108.
Alain Lenoir Stéphanie Depickère Séverine Devers Jean-Philippe Christidès Claire Detrain 《Journal of chemical ecology》2009,35(8):913-921
The cuticular hydrocarbons (CHCs) of the ant Lasius niger are described. We observe a high local colony specificity of the body cuticular profile as predicted for a monogynous and
multicolonial species. The CHCs show a low geographical variation among different locations in France. The CHCs on the legs
also are colony specific, but their relative quantities are slightly different from those on the main body. For the first
time, we demonstrate that the inner walls of the ant nest are coated with the same hydrocarbons as those found on the cuticle
but in different proportions. The high amount of inner-nest marking and its lack of colony-specificity may explain why alien
ants are not rejected once they succeed in entering the nest. The cuticular hydrocarbons also are deposited in front of the
nest entrance and on the foraging arena, with a progressive increase in n-alkanes relative amounts. Chemical marks laid over
the substrate are colony specific only when we consider methyl-branched alkanes. Our data confirm that these “footprint hydrocarbons”
are probably deposited passively by the contact of ant tarsae with the substrate. These results suggest that the CHCs chemical
profiles used by ants in colony recognition are much more complex than a single template: ants have to learn and memorize
odors that vary depending on their context of perception. 相似文献
109.
A review of Advances in Chromatography, Vol. 38. 相似文献
110.
Beckwith Leila; Cohen Sarale E.; Hamilton Claire E. 《Canadian Metallurgical Quarterly》1999,35(3):693
A prospective longitudinal research study of 86 prematurely born children from birth to age 18 years provided empirical evidence for continuity from infancy experience to representations of attachment at age 18 years. Young adults whose representation of attachment was dismissing had been objectively observed during infancy, 16–17 years earlier, to receive less sensitive maternal care than those infants who were later judged at early adulthood to have secure or preoccupied representations. Infancy experience alone did not differentiate young adults with secure representations from those with preoccupied representations. Rather, adverse life events through age 12, particularly parental divorce, reduced the likelihood of secure representations and increased the likelihood of preoccupied representations. The absence of adverse life events did not increase the likelihood of security for those who had not experienced early sensitive caregiving. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献