不同环境因子对纳米羟基磷灰石在饱和填充柱中迁移规律的影响

选用石英砂填充柱模拟土壤体系,通过测量纳米羟基磷灰石（Nano-HAP）ζ电位、出流比等来考察不同环境因素（腐殖酸浓度、pH和离子强度）对其在饱和石英砂柱中迁移规律的影响.结果表明,随着腐殖酸浓度的增加,Nano-HAP胶体的ζ电位相应增加（绝对值增加）,吸附效率（α）相应降低,当溶液中腐殖酸浓度由0增加为10 mg/...     

高速公路汽车防碰撞模型仿真研究

随着高速公路的快速建设,交通事故迅猛增长.保证适当的车辆行驶距离是预防高速公路事故的有效手段.论文根据车辆制动规律和运行状态,得出行车安全距离模型,同时对模型中的参数进行了说明和分析.采用MATLAB软件对高速公路车辆的安全距离模型进行仿真分析,得出安全距离随车速和附着系数的变化规律,寻求既保证车辆安全行驶又不影响道路通行能力的合理的安全距离值,为降低高速事故率提供一定的依据.     

Natural area visitors' place meaning and place attachment ascribed to a marine setting

Investigations of place have often focused on either place meaning (utilizing interpretive designs) or place attachment (using quantitative measures). Rarely have researchers explored the association between place meaning and place attachment. Hence, this investigation was designed to explore how individuals' attachment to a natural environment is reflected in their depictions of why the resource is meaningful.     

Defining place attachment: A tripartite organizing framework

Place attachment has been researched quite broadly, and so has been defined in a variety of ways. The various definitions of the concept are reviewed and synthesized into a three-dimensional, person–process–place organizing framework. The person dimension of place attachment refers to its individually or collectively determined meanings. The psychological dimension includes the affective, cognitive, and behavioral components of attachment. The place dimension emphasizes the place characteristics of attachment, including spatial level, specificity, and the prominence of social or physical elements. In addition, potential functions of place attachment are reviewed. The framework organizes related place attachment concepts and thus clarifies the term. The framework may also be used to stimulate new research, investigate multidimensionality, create operational definitions for quantitative studies, guide semi-structured interviews for qualitative studies, and assist in conflict resolution for successful land-use management.     

Place attachment and place identity: First-year undergraduates making the transition from home to university

This paper examines the issues emanating from the transition into a new social and cultural environment distant from the home, the context of which is provided by the transition from home to university. The study analyses the transitional process over a period of 5 months, using data obtained from in-depth semi-structured interviews and participant observation of ten first-year undergraduates who moved to study at the University of Gloucestershire in Cheltenham. It explores the mediating variables that impact place attachment and place identity during the transition from home to university. Within this context consideration is given to how participants made sense of changes in their socio-spatial environment, the ensuing problems and challenges of doing so, and how these meanings affected self-perceptions and self-evaluations. The analysis demonstrates how participant's stories of the transition evince an abiding concern with the loss of place, manifest in terms of an erosion of a sense of belonging, attachment and continuity and an undermining of home's capacity to symbolise the self. The implications of such accounts for our understanding of place attachment and identity are then explored. The paper concludes by advocating a holistic approach to our conceptualisation of place, given that place meanings are constantly being evaluated and redefined in light of changing social and physical relationships with place and between people and place.     

地方依恋有助于提高农户村庄环境治理参与意愿吗?——基于湖北省调查数据的分析

在农村社会转型背景下,从人地关系视角探讨农户地方依恋对其村庄环境治理参与意愿的影响,对剖析农村环境治理难题意义重大。以湖北省为例,利用1074份农户微观调查数据,从环境心理学视角下的人地关系出发,探讨了地方依恋对农户村庄环境治理参与意愿的影响,并进一步运用工具变量法(IV-Oprobit)进行内生性处理与稳健性检验。结果表明:①农户地方依恋水平整体一般,通过提高农户对村庄的依恋水平,可显著提升其村庄环境治理参与意愿。具体而言,农户地方依恋水平每提高1个单位,可使其环境治理“非常愿意”参与的概率提升35.51%。②社会信任在地方依恋对农户村庄环境治理参与意愿影响中发挥显著的调节和中介作用。一方面,地方依恋对农户村庄环境治理参与意愿的影响会随着农户社会信任水平的提高而不断增强;另一方面,地方依恋能够显著增强农户社会信任水平,从而提升其村庄环境治理参与意愿,即社会信任是地方依恋影响农户村庄环境治理参与意愿的重要传导中介,中介效应占总效应的比重为23.37%。③代际差异分析表明,在新生代和老一代农民群体中,地方依恋对其村庄环境治理参与意愿影响均显著。此外,性别、环保意识和环保态度等对农户村庄环境治理参与意愿也产生显著影响。据此,应加强村庄基础设施和文化建设等,不断增强农户的村庄认同感和依恋感,进而在美丽乡村建设中提升农户村庄环境治理参与水平。     

Ways to make people active: The role of place attachment, cultural capital, and neighborhood ties

This paper tries to reconcile two sets of apparently contradictory results. One is the positive link, postulated in literature, between place attachment and civic activity, the other is the sociological claim that there is a negative relationship between place attachment and a person's social and cultural status (cultural capital), which in turn is known to be the strongest positive predictor of civic involvement.In order to resolve this inconsistency, I postulated two alternative paths leading to civic activity: the social–emotional path, in which the relationship between place attachment and civic activity is mediated by local social capital (neighborhoods ties), and cultural path, consisting of cultural capital and interest in own roots. I also postulated a negative link between place attachment and cultural capital.A representative sample of 1328 subjects, coming from three regions of Poland, differing in historical heritage and objective rootedness of inhabitants, was used for analysis. In a series of structural equations, the two-path model was confirmed both in the whole sample and in each of the three regions separately. Similar results were obtained from a separate analysis run on data clustered into 114 communes.     

天然有机物和电解质对水中 C60凝聚行为的影响

以富勒烯(C60)纳米颗粒稳定悬浮液为对象,采用动态光散射技术研究了天然有机物和电解质对其在水中凝聚行为的影响.结果表明,采用甲苯溶剂替换法制备的稳定悬浮液中C60浓度为20 mg·L-1左右,表面呈较高的电负性,粒径在120 nm左右,具有较强的稳定性.投加简单电解质可通过压缩双电层机制使其发生凝聚,并符合经典的胶体稳定性(DLVO)理论.Mg Cl2和Ca Cl2的临界凝聚浓度分别为9.6 mmol·L-1和6.7 mmol·L-1.腐殖酸(humic acid,HA)存在时,投加Na Cl和Mg Cl2可使C60颗粒间有效碰撞概率及凝聚反应速度降低,临界凝聚浓度提高;HA可通过增大C60颗粒间的空间位阻效应,抑制凝聚反应发生,提高其在水中的稳定性.但Ca2+可与HA间发生络合反应,并对C60纳米颗粒产生吸附架桥作用,导致凝聚速度大幅提高,强化凝聚反应发生.水中C60纳米颗粒的凝聚和分散行为将受到有机物性质和电解质种类等复杂因素的影响.     

Place attachment and place identity in natives and non-natives

Place attachment is an affective bond that people establish with specific areas where they prefer to remain and where they feel comfortable and safe. Place identity, however, has been defined as a component of personal identity, a process by which, through interaction with places, people describe themselves in terms of belonging to a specific place. Most research has observed positive correlations between these variables in populations that have maintained ongoing interactions over long periods of time. This work presents two studies in which we compare place attachment to place identity in samples differentiated according to birthplace and length of residence, and the magnitude of these bonds to different places. The results of the first study revealed differences between intensity of attachment and identity depending on place of origin and place assessed. The second study found that identity and attachment tend to coincide in natives, while individuals from other places give higher scores for attachment than for identity. Results from the two studies have enabled us to consider that place attachment develops before place identity, at least in the case of the non-natives. Both studies reveal that bonds are stronger with the city than with the neighbourhood, but that attachment and identity with the island are stronger than either of them.     

外立面作用下水平湍流浮力射流火焰的附壁研究

用防火板模拟建筑外立面,设计了可控流速和开口尺寸的气体燃烧器产生水平湍流浮力射流火焰,系统研究了外立面抑制火焰卷吸所导致的水平湍流浮力射流火焰附壁规律。将火焰流场演变分为两个阶段:(1)出口到流场水平动量衰减为零(等价点)的阶段;(2)火焰附壁或不附壁的阶段。其中,火焰附壁与否很大程度上取决于等价点到出口的水平距离LE。通过分析,我们发现雷诺应力是导致流场水平动量衰减和火焰附壁的主要原因。由此,我们基于普朗特混合长度理论推导了雷诺应力的近似表达式并结合动量控制方程,获得了LE与修正弗洛德数Fr*的线性关系,从理论上解释了出口宽高比n(n=B/H,B是开口宽度;H是开口高度)越大,火焰越容易附壁的现象,并确定了不同开口及流速条件下,火焰附壁的临界条件。