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1.
《Geoforum》2014
The Transition Movement, originating in Ireland and the United Kingdom, gathers and supports community-led actions to meet the global challenges of climate change, peak oil and energy descent. In our study we analysed a Transition Network project, a Danish village built from scratch by its inhabitants and named the Self Sufficient Village (SSV). Employing the theories of constructed landscapes and place attachment, we studied how the Transition Movement ideology shaped the constructed landscape of the village and influenced the inhabitants’ attachment. The research team, following the grounded theory approach, conducted a field study staying in SSV. We collected data with focus groups, individual interviews and participatory observations, taking part in daily life of the community. The analysis revealed three, intertwined themes which altogether create the constructed landscape of SSV. They were named Community, Ideology, and Individual impact, respectively. Our findings showed that the community and strong social ties were predominant factors in shaping place attachment. Transition ideology and environmental awareness, although less pronounced, still turned out to be vital for the feelings of belongingness and empowerment, resulting in a positive impact of the village on the local scale. Using our case study as an example we discuss the importance of environmental concern and place attachment for similar grass-root initiatives. 相似文献
2.
A New Ichnogenus Kailidiscus Produced by Attachment from the Middle Cambrian Kaili Formation in Taijiang, Guizhou Province, China 总被引：1，自引：0，他引：1
WANG Yue 《《地质学报》英文版》2006,80(1):27-37
Over 190 specimens of an attachment ichnofossil Kailidiscus （n. ichnogen.） have been found in the Kaili Bitoa, a Burgess Shale-type biota, from the middle Kaili Formation （early Middle Cambrian） in Taijiang County, Guizhou Province, southern China. Kailidiscus is an epichnia with a circular to oval attachment platform, on which there is a carbonaceous film probably formed by the body of the living organism. Structures such as a marginal furrow, an inner and outer marginal ride, many convex fold-ridges, and a large caved peripheral furrow on the attachment platform may be the result of basal tissues of a sessile organism that wrinkled to increase the attachment＇s surface area. The Kailidiscus organism may have been a sessile cnidarian attached to the muddy seafioor. Kailidiscus organisms lived in relatively quiet water, and were buried by a sudden influx of sediment. 相似文献
3.
Holley Jason R. McComas Katherine A. Lambert Catherine E. Snider Natalie P. Tucker Grace K. 《Natural Hazards》2022,113(1):615-640
Natural Hazards - Drawing from protection motivation theory (PMT), we examined how place attachment and negative emotions, alongside threat and coping appraisals, personal experiences, and... 相似文献
4.
A trace fossil, Centrichnus eccentricus, was found beneath a saddle oyster (Anomia ephippium) that was preserved undisturbed on its substratum (a shell of Pecten jacobaeus), at the site of attachment of the calcified byssus. 相似文献
5.
《International Journal of Mineral Processing》2005,78(1):11-21
It has been shown in recent years that the long-range attractive interaction forces between hydrophobic surfaces in aqueous systems are caused by the capillary forces of gas bridges which form at the coalescence of nanobubbles adhering on the surfaces. The coalescence of nanobubbles on selectively hydrophobized particles with coarser bubbles initiates the jump into the three-phase contact at the attachment events in flotation. Therefore, one should no longer speak of hydrophobic forces in these events but of hydrophobic effects because they are caused by capillary forces. However, in the selective hydrophobization of particles by long-chain collectors (surfactants), there is another situation. Here, the association of nonpolar groups in the adsorption layers plays an important role in the energy balance of adsorption. This association is caused by “truly” hydrophobic interactions, which support the spotty distribution of the adsorbed collector ions on the particle surfaces and promote the formation of nanobubbles. This paper is intended to show to what extent the results obtained by basic research on the nanobubble formation as well as the force–distance dependence of collision events can be applied to flotation processes. This particularly requires the consideration of the highly turbulent flow conditions in the impeller stream of the flotation machines, in which the attachments almost exclusively occur. Various phenomena which occur in these machines and affect the reagent regime and the hydrodynamics point to the fact that nanobubbles can form, exist and even grow into microbubbles in that region. Therefore, so-called combined attachment events should predominate as already imagined several decades ago. The highly turbulent pressure fluctuations in the impeller stream in addition to the dispersion of the bubbles effect also their oscillations in size and shape, so that adsorption equilibria in the interfaces liquid/gas cannot be supposed. However, the pressure fluctuations present the possibility to overcome potential barriers in the wetting films at attachment events. 相似文献
6.
Field and laboratory observations on an association of cobia,Rachycentron canadum with cownose ray,Rhinoptera bonasus are reported. Cobia main-tained a position in close proximity to the back of the rays. The cobia would move away from the rays to take food presented. This opportunistic and probably facultative feeding on rejected food scraps or displaced benthos may be the first step in the evolution of commensal attachment as has been shown for the remoras. 相似文献
7.
《Chemical Geology》2006,225(3-4):230-243
Many minerals exhibit oscillatory zoning (OZ), whereby their chemical composition varies more or less regularly along a crystal core-to-rim profile. A well-known example of oscillatory zoning was previously obtained in the (Ba,Sr)SO4 solid solution system under controlled laboratory conditions. The OZ crystals were precipitated at room temperature from counter-diffusing aqueous solutions. In this contribution, we review a macroscopic model for the self-organized formation of oscillatory zoning in such binary solid solution. The model combines diffusive solute transport and an autocatalytic continuous crystal growth with a rate dependent on the mineral surface composition. Oscillatory solutions are obtained. It is also shown that fluctuations in the aqueous solution concentrations may contribute to the OZ formation by causing noise-induced transitions in the crystal growth regimes. We also present, for the first time, a cellular automata-based microscopic model, which considers diffusive motion and autocatalytic attachment kinetics of individual molecular units. OZ is obtained when the probability of attachment of a unit onto the crystal surface is calculated from the crystal composition averaged over the crystal surface (mean-field approach). However, OZ fails to develop when this probability is calculated from the local crystal composition at the attachment site in the absence of a lateral synchronization mechanism. 相似文献
8.
Yehoshua S. Cohen 《Geoforum》1987,18(4)
There is an abundance of literature on attachment to the residential neighbourhood and satisfaction with it. Efforts to explain variation in such attachment emphasise the relevance of population characteristics to the neglect of factors affecting attachment which are external to the neighbourhood's population. This article suggests a wide framework for analysis. The suggestion is made that a hierarchy of neighbourhood contexts could be used in order to reach a more complete explanation and understanding of attachment and variation in it to the residential neighbourhood. 相似文献
9.
Influence of surface roughness of the Teflon plates on kinetics of the bubble attachment was studied. Phenomena occurring during collisions of the air bubble, rising in clean water, with Teflon plates, differing only in their surface roughness, were recorded and analysed using a high-speed camera. Variations of the local velocity of the bubble during the collisions and the time of the bubble attachment were determined. It was found that the Teflon surface roughness was the parameter of a crucial importance for the attachment time of the colliding bubble. Depending on degree of the surface roughness the time of the attachment varied by over order of magnitude (from 3 to over 80 ms). In the case the Teflon surfaces having roughness below 1 μm there were recorded four to five “approach–bounce” cycles prior to the bubble attachment. Moreover, after the first collision the rapid pulsations of the bubble shape (within fraction of millisecond) were recorded. For surfaces of roughness ca. 50 μm and larger the attachment always occurred during the first collision—there was no bouncing observed and the time of the attachment was below 3 ms. It was documented that presence of a micro-bubble at the surface facilitated attachment of the colliding bubble. 相似文献
10.
C.R.C. Paul Michael J. Simms 《Proceedings of the Geologists' Association. Geologists' Association》2012,123(3):508-519
Ammonites with bivalves or worm tubes attached are relatively rare among the abundant specimens in the Lower Jurassic (Sinemurian) mudstones at Bishop's Cleeve, Gloucestershire, UK, but provide evidence for ammonite taphonomy, environmental conditions and biological interactions between ammonites and epifauna. Epifauna attached only to one side or within the body chambers of ammonites usually indicate post-mortem attachment. Epifauna on both sides of, or overgrown by, ammonites attached in vivo. One large example of Oxynoticeras has at least 51 encrusting bivalves attached exclusively to one side indicating it formed a ‘benthic island’. Four, presumably annual, bivalve cohorts are recognized, with variation in preferred orientation in each cohort suggesting that current direction varied. Both the ammonite and its epifauna were buried by a single sedimentation event. Other informative examples include a Cheltonia that overgrew an epifaunal bivalve, and an example of Bifericeras which bears two clusters of four worm tubes, one of which apparently attached in vivo, the other post-mortem. Other examples bear too few specimens to be certain of the timing of attachment, but most probably attached post-mortem. 相似文献
11.
通过一系列模型试验研究了倾斜荷载作用下吸力式沉箱基础的最佳作用点位置,试验中考虑了荷载作用点、荷载作用角度和长径比3个重要因素。基于模型试验得到的荷载-位移曲线,采用合适的破坏标准确定了各工况下吸力式沉箱基础的抗拔承载力,根据承载力的变化规律分析确定了吸力式沉箱基础的最佳作用点位置。结果表明,荷载作用角度对吸力式沉箱基础承载力的影响显著,当荷载水平作用于基础时,其承载力最大。荷载作用点位置对吸力式沉箱基础承载力的影响取决于荷载作用角度的大小,当荷载作用角度较小时,荷载作用点位置的影响显著,且最佳作用点位置位于沉箱高度的2/3～3/4处;当荷载作用角度较大时,荷载作用点位置的影响很小,可以忽略。结合荷载与吸力式沉箱基础的转角关系,分析了荷载水平作用于最佳作用点下吸力式沉箱基础的破坏模式。 相似文献
12.
为了研究不同上游来流速度型变化对立方体顶部表面是否会在前角附近产生分离、分离程度和附着情况,在对有关的实验数据进行分析比较的基础上,使用标准k-ε模型,说明立方体顶部在什么情况下会出现回流和附着,并提出附着长度ZR和上游来流速度型u=y1/m直接相关。同时计算结果表明：ZR随着m的减小而增大;当m大于7时,在立方体块上部产生较严重的分离而不会有附着,这时出现ZR>1.0。 相似文献
13.
地下环境中可移动的胶体能够促进强烈吸附的污染物质的运移,而胶体自身在运移过程中也会伴随发生沉淀、释放。根据高岭石胶体的土柱出流实验,对不同离子强度条件下胶体在饱和多孔介质中的沉淀和释放行为进行分析,并采用不同模型对其过程进行数值模拟。结果表明,离子强度是影响胶体沉淀和释放过程的重要因素,随着离子强度的增加,胶体的出流峰值逐渐降低,即胶体在多孔介质中的沉淀量逐渐增大,且沉淀速率系数K d 与离子强度成正相关;模型拟合的释放系数与NaCl 浓度显著相关,Grolimund 模型可以很好地模拟胶体的沉淀过程（R 2 >0.95）,但不能准确地模拟释放过程;而胶体运移方程耦合溶质运移方程能够模拟不同离子强度影响下胶体的释放过程（R 2 >0.9） 相似文献
14.
Guilherme A. R. Gualda Mark S. Ghiorso 《Contributions to Mineralogy and Petrology》2007,154(4):479-490
The fate of pre-eruptive bubbles depends largely on their buoyancy, which can be strongly modified by the presence of crystals
attached to the bubble–melt interface. We define the attachment energy and attachment force as those resulting from the attachment
of a crystal to a bubble. The attachment energy is such that (1) attachment of crystals to bubbles is always favored energetically,
and (2) oxide minerals attach to bubbles much more strongly than silicates, because the attachment energy is a strong function
of the wetting angle. Attaching crystals to bubbles can cause bubble–crystal pairs to become neutrally buoyant. There is a
critical bubble radius below which the attachment force will be strong enough to keep the pair together; we show that crystals
as large as 1 mm in diameter can form neutrally buoyant pairs. For early erupted Bishop magma, if all magnetite forms neutrally
buoyant pairs with gas bubbles, ca. 0.1–0.2 vol% gas can be stored in the magma; 2–3 vol% of gas can be accounted for if all
minerals form neutrally buoyant aggregates. These values are an order of magnitude lower than what is inferred from melt inclusions.
Hence, both magnetite-free and magnetite-rich bubbles might have existed, but only a very small fraction of them could have
been neutrally buoyant. Importantly, an intrinsic association between magnetite crystals and bubbles is expected. However,
most magnetite crystals in the early erupted Bishop are free of bubbles; the puzzling conclusion is that nucleation away from
crystals is favored over heterogeneous nucleation on crystal substrates.
Electronic Supplementary Material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
15.
Schizolepis daohugouensis sp. nov. is described from the Jurassic sediments of Daohugou flora, from Ningcheng County, Inner Mongolia Autonomous Region, China. The female cone is slender, cylindrical in shape, seed scale complexes are loosely and helically arranged on the cone axis at intervals of 3–5 mm. The seed scales are bilobed and divided almost from the base; the scales have no evident petiole but an articulation at the region of attachment to the cone axis. Each lobe of the seed scales is oval in shape, widest at the lower middle part; lobes are obtusely pointed with entire margins. Bract scale is fan shaped. Based on the records of Schizolepis, this is the first report of the occurrence of female cone of Schizolepis with the seed scales, the winged seeds and vegetative branches preserved together in the Jurassic deposits. The new discovery provides evidence that confirms the phylogenetic position of Schizolepis to the extant Pinaceae. 相似文献
16.
本文通过调查问卷方式,应用事故倾向性量表(APS-CW)、亲密关系经历量表(ECR)和一般自我效能感量表(GSES),以方差分析、相关分析、回归分析为主要的统计方法,探讨施工人员的成人依恋、事故倾向性及两者的关系,表明施工人员的依恋维度高低对事故倾向性具有一定的影响。 相似文献
17.
Zsuzsanna Balogh-Brunstad C. Kent Keller Forrest Stevens Bernard T. Bormann 《Geochimica et cosmochimica acta》2008,72(11):2601-2618
Ectomycorrhiza-forming fungi (EMF) alter the nutrient-acquisition capabilities of vascular plants, and may play an important role in mineral weathering and the partitioning of products of weathering in soils under nutrient-limited conditions. In this study, we isolated the weathering function of Suillus tomentosus in liquid-cultures with biotite micas incubated at room temperature. We hypothesized that the fungus would accelerate weathering by hyphal attachment to biotite surfaces and transmission of nutrient cations via direct exchange into the fungal biomass. We combined a mass-balance approach with scanning electron microscopy (SEM) and atomic force microscopy (AFM) to estimate weathering rates and study dissolution features on biotite surfaces. Weathering of biotite flakes was about 2-3 orders of magnitude faster in shaken liquid-cultures with fungus compared to shaken controls without fungus, but with added inorganic acids. Adding fungus in nonshaken cultures caused a higher dissolution rate than in inorganic pH controls without fungus, but it was not significantly faster than organic pH controls without fungus. The K+, Mg2+ and Fe2+ from biotite were preferentially partitioned into fungal biomass in the shaken cultures, while in the nonshaken cultures, K+ and Mg2+ was lost from biomass and Fe2+ bioaccumulated much less. Fungal hyphae attached to biotite surfaces, but no significant surface changes were detected by SEM. When cultures were shaken, the AFM images of basal planes appeared to be rougher and had abundant dissolution channels, but such channel development was minor in nonshaken conditions. Even under shaken conditions the channels only accounted for only 1/100 of the total dissolution rate of 2.7 × 10−10 mol of biotite m−2 s−1. The results suggest that fungal weathering predominantly occurred not by attachment and direct transfer of nutrients via hyphae, but because of the acidification of the bulk liquid by organic acids, fungal respiration (CO2), and complexation of cations which accelerated dissolution of biotite. Results further suggest that both carbohydrate source (abundant here) and a host with which nutrients are exchanged (missing here) may be required for EMF to exert an important weathering effect in soils. Unsaturated conditions and physical dispersal of nutrient-rich minerals in soils may also confer a benefit for hyphal growth and attachment, and promote the attachment-mediated weathering which has been observed elsewhere on soil mineral surfaces. 相似文献
18.
《International Journal of Mineral Processing》2003,68(1-4):47-69
A particle–bubble attachment apparatus, similar to that used by Whelan and Brown [Bull. Inst. Min. Met. Trans. 65 (1956) 181] is developed to study free falling glass beads (dp=131 μm) with different surface treatment attaching to a stationary air bubble (db=3 mm). The entire process of the particle–bubble attachment is photographically recorded using a high framing-rate camera and analyzed frame by frame. It is found that the hydrophilic particle slides on the top half of the bubble, and then the particle leaves the bubble, as anticipated. The particle sliding velocity increases with increasing angular position on the bubble surface. For the hydrophobic particle, it was found that the particle slides over the entire bubble surface without detaching from the bubble. The sliding velocity, however, reaches a maximum at an angular position of 90–100°, and then slows down to zero. A smaller sliding velocity is obtained for the hydrophobic particle than that of the hydrophilic particle at a given angular position. The attachment efficiency for the hydrophobic particle reduces with increasing initial angular positions, suggesting that the hydrophobicity alone does not directly guarantee the attachment to a bubble. Adding surfactant (sodium dodecyl sulfate [SDS]) to the test solution makes the hydrophobic particle become less hydrophobic or even hydrophilic, thereby decreasing the attachment efficiency. A much longer induction time is obtained in our present work than that reported in the literature. A simplified particle sliding velocity and attachment model is developed, and a good agreement between the theoretical prediction and experimental measurement is obtained. 相似文献
19.
20.
Specimens of a free-living copepod, Cyclops bicuspidatus thomasi, were found attached to striped bass and white perch larvae collected in the Chesapeake and Delaware Canal and adjacent waters. Damage to most of the larvae was constriction of tissue around the point of attachment, but some exhibited more severe damage such as missing parts of the finfold or a ruptured yolk sac. Most of the larvae had damage which was extensive enough to have caused death. 相似文献