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991.
Le Trinh Hai Pham Hoang Hai Tran Anh Dung Luc Hens 《Environment, Development and Sustainability》2010,12(1):103-116
Background Sustainable development (SD) is a common concept. Knowledge and attitudes are essential in the SD process. This study assesses
the knowledge, attitudes, and practices (KAP) of local people about SD. Aim To study the factors that influence the understanding of the concept, contents, and indicators of different aspects affecting
the health and environmental issues. Methods A cross-sectional study was carried out from June to July 2007 among 546 households in the Quang Tri province. Data were
gathered on basis of socio-demographic variables, namely age, gender, education, occupation, income, and region. Chi square
tests and multivariate analysis were performed on the obtained data. The data were cleaned and analysed using SPSS 15.0 for
windows. Results Occupation is related to knowledge, attitude, or practice. Income is related to knowledge or practice. Gender related to
only attitude. Lastly, region is related to attitude or practice. The proportion of wrong understanding about SD is 2.0 times
(95% CI: 1.3; 3.1, p < 0.001) higher than that of the people who have good understanding about it. The rate of willingness to do any related SD
programmes of the people who understanding is 2.1 times (95% CI: 1.4; 3.2, p < 0.001) higher than that of the people who have bad one. Conclusions This study shows that knowledge on sustainability of the local communities is low. Occupation and income influence understanding
of SD more than region, age, gender, and education. Most of the local people who do not understand SD in general, do not want
to participate or act in SD programmes. 相似文献
992.
几种模拟处理方式污泥淋出液重金属与养分特征 总被引:2,自引:0,他引:2
为了减少城市污泥重金属对农田的污染,更好地实现污泥农业资源化利用,通过盆栽实验研究不同处理(对照、黑网、附Fe黑网、附Fe黑网+K2SO4及附Fe黑网+玉米)对城市污泥淋出液重金属和养分含量等的影响。结果表明,黑网可降低污泥淋出液的Zn﹑Cd总量,且没有减少污泥淋出液中氮、磷和钾的总量。Fe(OH)3可使淋出液中Zn总量降低,但同时也显著减少了淋出液中的磷总量。K2SO4可降低淋出液中的Cu总量,且促进Fe结合磷的释放。玉米的种植可使污泥的总重降低,同时玉米籽粒和茎叶重金属含量达到饲料标准。综合来看,任何处理每次淋出液的Cu、Zn、Pb、Cd浓度均符合农田灌溉水标准,淋出液氮、磷、钾量占原污泥中氮、磷、钾总量的比例(0.98%~9.88%)远远大于重金属元素(Cu,Zn,Pb,Cd)占原污泥对应重金属总量的比例(0.04%~0.41%),污泥淋出液作为农田灌溉水进行肥水利用将是污泥农业资源化利用的适合途径,同时黑网+玉米处理可能是较理想的污泥综合处理利用方式。 相似文献
993.
994.
995.
N. Gruchy F. Vialard E. Blondeel N. Le Meur G. Joly-Hélas P. Chambon M. Till M. Herbaut-Graux A. Vigouroux-Castera A. Coussement J. Lespinasse F. Amblard M. Jimenez L. Lebel Roy Camille F. Carré-Pigeon E. Flori F. Mugneret S. Jaillard C. Yardin R. Harbuz M. Collonge Rame P. Vago M. Valduga N. Leporrier 《黑龙江环境通报》2014,34(12):1133-1138
996.
Marguerite Miguet Julien Thevenon Vincent Laugel Mathilde Lefebvre Aurélie Bourchany Jean-Baptiste Rivière Yannis Duffourd Elise Schaefer Maria Cristina Antal Rosalie Abida Anne-Sophie Weingertner Valérie Kremer Pierre Vabres Fanny Morice-Picard Marie Gonzales Dan Lipsker Sylvie Fraitag Jean-Louis Mandel Jamel Chelly Hélène Dollfus Laurence Faivre Christel Thauvin-Robinet Nadège Calmels Salima El Chehadeh 《黑龙江环境通报》2016,36(13):1276-1279
997.
998.
为了利用声发射技术对钢筋混凝土构件损伤进行定量检测,将矩张量在地震工程学中反演震源机制的理论用于结构的声发射无损检测。阐述了基于矩张量理论的声发射检测技术原理,推导了利用矩张量理论反演裂缝机制(裂缝位置、类型和走向)的定量表达式。通过钢筋混凝土梁的四点弯曲试验,按照基于矩张量的声发射分析方法,明确裂缝机制,并与试验结果比较,探讨矩张量理论用于钢筋混凝土结构无损检测的有效性。结果表明:对于钢筋混凝土受弯构件,基于矩张量的声发射无损检测技术能定量地描述结构的裂缝机制,具有较好的准确性。 相似文献
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1000.
Stone provisioning is a nest-maintenance activity accomplished by pygoscelid penguins after reliefs during the incubation/brooding period. The functional significance of this behaviour has been mainly explained as a parental strategy preventing nest flooding under detrimental weather conditions. In addition, and in the light of recent studies, this behaviour could also fit into the sexual selection process. In this study, we tested the first idea, that is, whether stone provisioning is a nest-maintenance behaviour to increase egg/nestling survival by lowering the risk of nest flooding, and can thus be considered a form of parental care. Additionally, we investigated if the effort invested by parents in nest maintenance is constrained by physiologically limiting resources. The effort of stone collection and the perceived risk of nest flooding were experimentally manipulated during the incubation and early brooding phases in a chinstrap penguin, Pygoscelis antarctica, colony. Three groups of nests were established. After weighing, control nests were left unmanipulated. In a second group of nests (reduced group), only one-half of the initial weight of stones was returned to the nests. In a third group of nests (snow-added group), we both reduced nest weight by a half and added snow outside the nest bowl over 6 consecutive days. Ten days after manipulation, the difference in nest weight between initial and final conditions was significantly related to treatment: penguins increased stone provisioning in the reduced group (44% of half-reduced nests), but drastically more in the reduced and snow-added group (123% of half-reduced nests), while the weight of control nests was unchanged compared to premanipulation conditions. The intensity of stone provisioning was affected by nest date, peaking about hatching time and shortly after, and declining with advancing chick age. These results suggest that stone provisioning is a mechanism that has evolved to prevent egg or chick mortality by nest flooding. The haematocrit, but not leukocyte numbers as expressed by the buffy coat layer, varied with the experimental conditions. Penguins investing more time in nest maintenance had a lower haematocrit, suggesting a physiological trade-off probably mediated by competition between the time devoted to nest maintenance versus foraging activities. The amount of stones collected and the haematocrit were positively related to the number of neighbour nests, so those individuals surrounded by more nests seemed to obtain benefits in the availability of nest material and energy savings. This study indicates that stone-provisioning behaviour is a nest-maintenance activity evolved to improve thermal nest characteristics potentially increasing offspring survival, and competing in time and energy with other reproductive activities. Stone provisioning in penguins should therefore be regarded as a form of parental care and an important part of individual reproductive effort in species breeding in harsh environments. Furthermore, nest size and nest-maintenance effort should be considered reproductive traits indicative of parental quality and thus could also be involved in the post-mating sexual selection process. 相似文献