腈纶废丝/硬脂酸相变纤维的制备及性能研究

以硬脂酸(SA)为相变储能物质,腈纶废丝(PAN)为聚合物基体,采用湿法纺丝法制备了PAN/SA相变纤维。研究表明,相变纤维中PAN与SA大分子依靠分子间作用力结合在一起;SA在纤维基体中分布均匀,无相分离现象;PAN/SA相变纤维的相变焓达到48.84J/g,且DSC热循环显示纤维具有较好的热稳定性;PAN/SA相变纤维相对于PAN纤维具有良好的保温性;PAN/SA相变纤维在110℃热空气中迅速干燥的力学性能优于常温处理的力学性能。     

To look or not to look: An eye movement study of hypervigilance during change detection in high and low spider fearful students.

Previous eye movement studies of attentional bias in spider fear reported inconsistent results with respect to early attentional capture, suggesting that overt attentional capture only reliably occurs under specific circumstances. In addition, none of these studies explored covert attention. The present study examined attentional bias in spider phobia using a change detection paradigm that was expected to provide good conditions for documenting attentional capture. In contrast to our expectations, eye movement data showed that all participants' first fixations were fastest on general negative targets, whereas participants' first fixations on spider targets were slower in the spider fearful than in the nonfearful group. In addition, spider fearful participants made more nontarget fixations before fixating on a spider target than did nonfearful participants. Thus, we found that participants' overt attention was more quickly focused on general negative targets, whereas covert attentional processes enabled initial avoidance of fear-relevant (i.e. spider) stimuli. The present findings have important implications for research on attention and fear as they indicate that fearful individuals are not characterized by static attentional orienting toward threat but, under certain conditions, may avert attention from threat automatically. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

Exploring climate change criteria for strategic environmental assessments

Climate change has become a high priority worldwide at the level of governments, business, and community due to growing understanding of climate change's implications for trade, security, the economy, ecosystems, and the well-being of humans and other species. The strategic environmental assessment (SEA) process is well-positioned to systematically help strengthen treatment of climate change adaptation and mitigation in planning and development. This is due to its practical, analytical component, its participation component, and its ability to engage with ethical issues and reconcile competing agendas. This monograph explores criteria and good practices in addressing various climate change aspects in SEA and country environmental analysis (CEA). Climate change criteria are developed and applied to two datasets to provide an initial information baseline on climate change treatment in SEA and CEA, amended sets of climate change criteria for each, and an evidence-based resource for improving SEA and CEA guidance and practice amongst interested academics, professionals, and practitioners in the UK, EU, development banks, and developing countries. Overall findings are relevant to any individual, institution, or country interested in addressing climate change and climate-related natural hazards within an SEA or planning framework.     

Singapore’s changing spaces

This paper interrogates the socio-spatial environment that is emerging in Singapore with its development of a globalised economy. Using the case studies of two of the city’s dichotomised spaces - the spectacular downtown and gentrified heartland - the paper seeks to examine the resulting spatial reconfigurations, challenges and unintended consequences. While the common assertion is that state-led planning is effective at the macro level, at the micro level against the accelerated change and emergence of the multi-layered package of spaces of globalisation, the planning of the city is no longer limited to physical planning. Like many emergent economies of the global south, the challenge of how to expand emerging sectors, support Singapore’s economic aspirations and meet social objectives remains.     

The impact of urbanization policy on land use change: A scenario analysis

The rapid urbanization has led to extensive land use change particularly in those developing countries. In line with the development of urbanization, arable land is decreasing dramatically, which presents the threat to the food security for human being. It is therefore essential to understand the level of impacts of urbanization on the land use change. This paper introduces a dynamic systems based method for assessing the impacts of urbanization policy on land use change with reference to the urbanization practice in China. Four typical policy scenarios are identified in implementing urbanization in China, including balanced development driven by planning, uneven development driven by planning, balanced development driven by market and uneven development driven by market and their impacts on land use change are analyzed through a dynamic system model. Land use change is considered as a dynamic system model composing five subsystems: urbanization, social, economic, environmental and land use subsystems. The key attributes in these five subsystems are interactive and they are dynamic variables. The assessment on the impacts of urbanization policy to land use change is demonstrated through employing the software iThink to the land use change dynamic model, using the data collected from the Jinyun County in China. The findings suggest that the urban construction land will continue to increase in the foreseeable future in China, whilst the agricultural land will gradually decrease. Nevertheless, different policy scenarios will have different impacts on these land changes. Thus decision makers can adopt different policies to control the rate of land use change.     

Future trends of building heating and cooling loads and energy consumption in different climates

Principal component analysis of dry-bulb temperature, wet-bulb temperature and global solar radiation was considered, and a new climatic index (principal component Z) determined for two emissions scenarios – low and medium forcing. Multi-year building energy simulations were conducted for generic air-conditioned office buildings in Harbin, Beijing, Shanghai, Kunming and Hong Kong, representing the five major architectural climates in China. Regression models were developed to correlate the simulated monthly heating and cooling loads and building energy use with the corresponding Z. The coefficient of determination (R²) was largely within 0.78–0.99, indicating strong correlation. A decreasing trend of heating load and an increasing trend of cooling load due to climate change in future years were observed. For low forcing, the overall impact on the total building energy use would vary from 4.2% reduction in severe cold Harbin (heating-dominated) in the north to 4.3% increase in subtropical Hong Kong (cooling-dominated) in the south. In Beijing and Shanghai where heating and cooling are both important, the average annual building energy use in 2001–2100 would only be about 0.8% and 0.7% higher than that in 1971–2000, respectively.     

Heat and cold stresses in different climate zones across China: A comparison between the 20th and 21st centuries

Summer and winter discomfort in terms of heat and cold stresses in the nine major architectural climate zones and sub-zones across China in the 21st century were investigated using predictions from general circulation models for the low and medium emissions scenarios. For the six severe cold and cold climate zones in the north, reductions in cumulative cold stress outweighed the increase in cumulative heat stress resulting in an overall decreasing trend in the annual cumulative stress, and vice versa for the other three warmer climate zones in the south. Compared with the 20th century, significant reduction in the cumulative cold stress was observed across the six zones in severe cold and cold climates, ranging from 15.8 in cold-III to 42.3 in severe cold-II. There were modest increases in the cumulative heat stress from 0.3 in cold-II to 12.3 in cold-III. For the warmer climates in the south, reduction in cumulative cold stress ranged from 7.6 in hot summer and warm winter (HSWW) to 10.3 in hot summer and cold winter, while cumulative heat stress increased from 9.9 in the mild zone to 30.6 in HSWW. A reduction in cold stress would result in less winter heating and an increase in heat stress more cooling requirement.     

Longitudinal prediction of the operational energy use of buildings

Thus far most studies of operational energy use of buildings fail to take a longitudinal view, or in other words, do not take into account how operational energy use changes during the lifetime of a building. However, such a view is important when predicting the impact of climate change, or for long term energy accounting purposes. This article presents an approach to deliver a longitudinal prediction of operational energy use. The work is based on the review of deterioration in thermal performance, building maintenance effects, and future climate change. The key issues are to estimate the service life expectancy and thermal performance degradation of building components while building maintenance and changing weather conditions are considered at the same time. Two examples are presented to demonstrate the application of the deterministic and stochastic approaches, respectively. The work concludes that longitudinal prediction of operational energy use is feasible, but the prediction will depend largely on the availability of extensive and reliable monitoring data. This premise is not met in most current buildings.     

Developing future hourly weather files for studying the impact of climate change on building energy performance in Hong Kong

The concern on climate change leads to growing demand for minimization of energy use. As building is one of the largest energy consuming sectors, it is essential to study the impact of climate change on building energy performance. In this regard, building energy simulation software is a useful tool. A set of appropriate typical weather files is one of the key factors towards successful building energy simulation. This paper reports the work of developing a set of weather data files for subtropical Hong Kong, taking into the effect of future climate change. Projected monthly mean climate changes from a selected General Circulation Model for three future periods under two emission scenarios were integrated into an existing typical meteorological year weather file by a morphing method. Through this work, six sets of future weather files for subtropical Hong Kong were produced. A typical office building and a residential flat were modeled using building simulation program EnergyPlus. Hourly building energy simulations were carried out. The simulated results indicate that there will be substantial increase in A/C energy consumption under the impact of future climate change, ranging from 2.6% to 14.3% and from 3.7% to 24% for office building and residential flat, respectively.     

动臂式塔机结构参数化计算分析平台LUSPAP的构建及实现

针对工程中常用的各类格构型动臂式塔机结构的力学建模及计算分析,开发出基于成熟有限元软件并融合国内外起重机设计标准的,交互式参数化动臂式起重机结构计算分析平台LUSPAP系统.该系统主要由建模前处理、有限元计算、后处理输出等3大部分组成.前处理通过Visual Basic和Visual Fortran进行几何图形库与材料...