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排序方式: 共有5631条查询结果,搜索用时 15 毫秒
31.
Palmer PM Wilson LR O'Keefe P Sheridan R King T Chen CY 《The Science of the total environment》2008,394(1):90-102
An investigation was carried out in the New York City Watershed for the presence of selected pharmaceuticals. In four seasonal sampling events between August 2003 and May 2004, surface water was collected from eight reservoir keypoints and effluent was collected from four wastewater treatment plants. We evaluated the following twelve compounds: amoxicillin, atenolol, caffeine, carbamazepine, cephalexin, estrone, 17alpha-ethinylestradiol, 17beta-estradiol, ibuprofen, sulfamethoxazole, trimethoprim, and valproic acid. In the treated effluents, carbamazepine was detected most frequently (100%; concentration range: 22-551 ng/L), followed by atenolol (94%; ND - 14,200 ng/L), trimethoprim (83%; ND - 37,000 ng/L), ibuprofen (61%; ND - 14,600 ng/L), and caffeine (49%; ND - 37,200 ng/L), while estrone was detected once (56 ng/L). In the reservoir keypoint samples, only ibuprofen (2.5%; ND - 932 ng/L) and caffeine (2.9%; ND - 177 ng/L) were detected. The other analytes were not detected in any sample. It is expected that investigation of other wastewater treatment plants in the New York City Watershed would show that their effluents are also a potential source of pharmaceuticals, but that these pharmaceuticals are unlikely to be detected in the Watershed's surface waters. 相似文献
32.
Szabo S Haislip AM Traina-Dorge V Costin JM Crawford BE Wilson RB Garry RF 《Microscopy research and technique》2005,68(3-4):209-221
Sequences highly similar (>95%) to the mouse mammary tumor virus (MMTV) env gene have been amplified from human DNA samples, including DNA samples from patients with breast cancer (BC) and persons who did not have BC. The sequences from human DNA were distinct from the MMTV sequences used as controls in these PCR reactions, indicating that these results are not simply due to contamination. In addition to both, mouse and human-related sequences were also amplified from some monkey and cat genomic DNA samples. These products were shown to be distinct from, but highly related to, the MMTV env gene, whereas, testing of other sources (lambda phage, snake, cockroach, sea urchin, chicken, or dog) demonstrated no specific amplification. A sequence 90% similar to the MMTV group antigen gene (gag) was amplified from cat DNA. These results indicate that DNA from vertebrate species other than rodents, including some but not all humans, monkeys, and cats, can contain sequences closely related to MMTV. 相似文献
33.
Alan Wilson 《Papers in Regional Science》2010,89(1):27-42
The general urban model is viewed in brief retrospectively, mainly emphasizing the transition for the monocentric 'classical' elements of such a model to the multicentric. The emphasis of the paper, however, is on future prospects. It is argued that it could be developed as the basis of a model-based 'big picture' of urban development through five layers of disaggregation – from the global to the local. There are many opportunities for submodel development but the main future challenge is the modelling of urban and regional evolution. Progress in modelling urban and regional systems as complex nonlinear systems with particular reference to path dependence and phase transitions is reviewed. The idea of urban and regional 'DNA' is introduced which leads to a 'genetic medicine' view of aspects of planning. 相似文献
34.
Tom Hargreaves Charlie Wilson Richard Hauxwell-Baldwin 《Building Research & Information》2018,46(1):127-139
ABSTRACTSmart homes promise to significantly enhance domestic comfort, convenience, security and leisure whilst simultaneously reducing energy use through optimized home energy management. Their ability to achieve these multiple aims rests fundamentally on how they are used by householders, yet very little is currently known about this topic. The few studies that have explored the use of smart homes have tended to focus on special-interest groups and be quite short-term. This paper reports on new in-depth qualitative data that explore the domestication of a range of smart home technologies in 10 households participating in a nine-month field trial. Four core themes emerge: (1) smart home technologies are both technically and socially disruptive; (2) smart homes require forms of adaptation and familiarization from householders that can limit their use; (3) learning to use smart home technologies is a demanding and time-consuming task for which there is currently very little support available; and (4) there is little evidence that smart home technologies will generate substantial energy savings and, indeed, there is a risk that they may generate forms of energy intensification. The paper concludes by discussing the implications of these findings for policy, design and further research. 相似文献
35.
36.
Alexander Bond Steven Benbow James Wilson Alain Millard Shigeo Nakama Myles English Christopher McDermott Benoit Garitte 《岩石力学与岩土工程学报(英文版)》2013,5(1):44-57
At Mont Terri Underground Research Laboratory (URL) Switzerland, a specific experiment has been performed in a tunnel, in order to investigate the hydro-mechano-chemical (HMC) perturbations induced in the argillaceous formation by forced ventilation. This experiment has been selected in the international project DECOVALEX to be used for process model development and validation. The numerical simulation of the geochemical response to the ventilation experiment (VE) is the object of the present paper, focusing on the transport of chloride as a conservative species and sulphate as a reactive species. Utilising the validated hydro-mechanical (HM) results from earlier steps of the DECOVALEX task, reactive and non-reactive transport models, incorporating the current understanding of the geochemistry at the site, were successfully constructed for the whole experimental period. The associated parametric and process uncertainty analyses clearly demonstrate that the basic HM understanding must be sound. However, to demonstrate this degree of robustness, the explicit inclusion of process representations of water desaturation, liquid vaporisation, species exclusion porosity, and redox processes, is required. 相似文献
37.
D.J. Wilson D.D.J. Netterville 《Journal of Wind Engineering & Industrial Aerodynamics》1981,7(1):55-64
The operating characteristics of a small, aspirated concentration sensor based on a hot-film anemometer are described. Constant aspiration velocity past the sensor produces a linear output over a wide range of tracer gas concentration, and a useful bandwidth of 0–500 Hz. A simple experimental technique for dynamic calibration is presented, with frequency response inferred from a model of the effects of molecular diffusion and hot-film response. 相似文献
38.
英雄式的现代主义致力于通过建筑建造一个个“乌托邦”,对这种现代主义的批判引发了当前面向日常生活主题的建筑潮流.它常常通过讽刺性的滑稽模仿触及现代建筑法则的痛处.卢克索剧院的设计在一定程度上是围绕观众进入剧院的路线展开的.观众从大街上进入剧院,盘旋而上到达不同楼层和环道端头的楼梯.环道环绕舞台和观众席而建,使观众席成为剧院的中心.这种便于观众流动的设计带给建筑的是一个自然的结构和无朝向性的外立面.外立面为纤维混凝土,这是一种普通的建筑材料.汽车坡道引人注目的大胆结构是所有建筑元素中最具挑战性的设计. 相似文献
39.
As extreme heat and weather events are predicted to increase due to global warming, the risk of human heat stress within buildings will increase. To be resilient, buildings will need the capacity to provide habitable indoor conditions without power for limited amounts of time. Additional indoor thermal standards are required for public health to address ‘passive habitability’ during power outages. Current research on building-related heat stress and numerous heat indices is examined in relation to the development of a new heat-safety metric for use in passively conditioned buildings. Most indoor overheating research relies on outdoor temperature data and has no common indoor heat index for evaluating indoor heat stress. A recommendation is made for using the wet-bulb globe temperature (WBGT) and predicted heat strain (PHS) indices for modelling and monitoring of indoor heat stress in healthy adult populations because both indices utilize the primary thermoregulation variables, have associated heat-stress thresholds, and can be assessed or tracked with existing environmental monitoring methods and predictive energy modelling techniques. Further research is recommended on health effects and exposure limits of vulnerable populations, and the variation in thermal factors within buildings and the building stock. 相似文献
40.
Carolina Pinto Rebecca Ing Ben Browning Vinicius Delboni Hazel Wilson Dominic Martyn Gemma L. Harvey 《Water and Environment Journal》2019,33(3):353-365
Large wood (re)introduction can deliver multiple benefits in river restoration, but there is a dearth of the detailed and longer‐term post‐project monitoring and evaluation required for improving best practice. We present findings from an academic partnership approach to post‐project evaluation, based on successive MSc research projects on restored large wood in the Loddon catchment, UK. Field and modelling data reveal: (i) key differences in large wood features between restored and natural reaches; (ii) increased hydraulic retention and changes to mesohabitats associated with large wood; (iii) differences in macroinvertebrate community composition around large wood but a lack of site‐level effects; (iv) interactions between macrophytes and large wood that may be specific to restored reaches; (v) a need for further field and modelling studies to inform the accurate representation of large wood in hydraulic models. Some key challenges in partnership working are identified to aid planning and effectiveness of future collaborations. 相似文献