天然气供气过程中气体成分的波动对民用燃气器具的影响

针对上海市天然气气源成分波动的特点,对市场上销售和使用的家用燃气灶具和燃气快速热水器进行了测试,得出了市场上销售的家用燃气器具在设计合理的条件下能够同时适应目前供应的两种天然气之结论。     

浅谈形状记忆合金

时代的发展离不开材料的发展。科学技术的进步,越来越体现出材料研究的重要性。现如今材料的研究逐渐倾向于功能化、多样性。形状记忆材料就是一种典型的新型功能材料。形状记忆材料是指具有形状记忆效应的金属、陶瓷和高分子等材料,在高温下材料形成一种形状,在冷却到低温时会塑性变形成为另外一种形状,如果对材料进行加热,通过马氏体的逆相变,又可以恢复到高温时的形状,这就是形状记忆效应。单程记忆、双程记忆和全方位记忆是形状记忆效应按形状恢复形式进行的三种分类,如下图所示。     

燃煤电厂中CO2的捕集

对燃煤电厂烟道气CO2的捕集进行了综述,并针对CO2的捕集方法(吸收分离法、吸附分离法、膜法、低温蒸馏法)和燃煤电厂捕获技术工艺路线(如:燃烧后捕集、燃烧前捕集、富氧燃烧捕集、化学链燃烧技术及以煤制氢为核心的近零排放技术)进行了较为详尽的分析和讨论.     

关于介孔材料的合成及其应用的研究综述

各种领域的技术进步要求开发结构可控的有序多孔材料,并系统定制孔结构。以几纳米为尺度的结构性能可以满足在涉及大分子例如生物和石油产品的过程中不断增长的应用需求。本文综述了表面活性剂合成介孔硅酸盐的机理及相应的合成途径、方法,以期为相关研究提供参考。     

改革《工程材料与机械制造基础》课程教学的几点体会

《工程材料与机械制造基础》作为我校工程教育的主干技术基础课和工程实践课，对提高学生的全面素质、培养高质量、高层次的工程应用型人才起着其他课程不能替代的作用。它是将原有的《金属工艺学》、《金属材料与热处理》、《金属切削原理及刀具》、《金属切削机床概论》、《机械制造工艺学》、《机床夹具设计》等课程进行有机的整合与重组而成的一门研究机械制造原理和方法的新课程，具有综合性、     

一台液化石油气球罐裂纹的原因分析及处理

2009年5月,笔者所在研究院在对省内某单位2000m3液化石油气球罐进行定期检验时,发现该球罐存在裂纹缺陷多处,已不能正常安全使用。 一、设备基本参数 设计压力为1.77MPa,设计温度为50℃,介质为液化石油气，直径为15700mm，材质为16MnR，设计厚度48mm。     

金属的腐蚀与防腐蚀

所谓金属的腐蚀是指金属表面和周围的介质发生了化学作用或电化学作用,而使金属受到损坏的现象.据统计.每年全世界有一亿吨以上的金属(主要是钢铁)因腐蚀而损失掉.腐蚀的危害不仅在于金属本身的损失,更为严重的是,因腐蚀而造成的设备的报废,甚至造成重大事故.因此研究腐蚀的原因及其有效防止的措施,就成为非常迫切的问题了.     

氢能

过去,氢主要作为化工原料。从20世纪70年代初以来,研究将氢用于发电、各种机动车和飞行器的燃料、家用燃料等。在作为能源使用时,无污染物产生,燃烧产物只是水,生产氢的原料也是水。它的热值高,每克液氢可达120KJ,是汽油的28倍。一般说,氢是一种清洁的能源。今后技术、经济过关,使用氢能可以解决因化石燃料而引起的环境、生态等严重污染问题。由于氢能的储运性能好,使用也方便,可转化性优于其它各类能源,安全性也与汽油相当。太阳能、风能、地热、核能、电能等均可转化成氢加以储存、运输或直接应用,氢是一种理想的载能体。随着科技进步,氢能开发利用很有前途。     

金属材料热处理的节能技术探究

科技的进步推动了我国金属制造业的发展。金属材料的热处理是金属制造过程的关键,金属材料热处理的节能技术是近年来金属制造业关注的重点。本文在分析金属材料热处理现状的基础上,对金属材料热处理的节能技术进行了概括,以期为金属材料热处理节能工作提供参考。     

冷凝式热水器的实验研究及优化分析

介绍冷凝式家用燃气热水器的实验研究结果,并结合实例对换热面积进行了优化分析。     

Becoming metal: narrative reflections on the early formation and embodiment of heavy metal identities

Heavy metal music has long been researched as a risk factor for youth development. Over the last decade, however, there has been a significant shift towards studies that are more sympathetic to metal fans, but still we know very little about young people’s pathways to forming metal identities. What is the allure of metal as an identity choice? What can be gained from the early embodiment of metal identities? To explore these questions, this paper reports on findings from qualitative research with metal youth in Australia that captured rich, narrative reflections on ‘becoming’ metal. The results show that metal was vitally important when participants felt vulnerable to bullying and exclusion by popular peers at school. But crucially, the young ‘metalheads’ were able to disrupt power relations at school by embodying ‘chosen’ heavy metal identities as a strategic response for countering ‘unchosen’ marginal school-based identities. The politically transformative properties of subculture at the level of the individual are revealed through ways that the metal youth, as self-described outsiders, were able to act alone to challenge dominant school norms and enter into social relationships on their own terms, protecting themselves from social threats to their mental health and well-being in the process.     

Female Authority and Dominion: Discourse and Distinctions of Heavy Metal Scholarship

From its inception, both outsiders and insiders have associated heavy metal with men and masculinity. Some have even maintained that metal culture is hostile territory for women. Despite this, a significant proportion of writers who have documented, analysed, and indeed celebrated heavy metal has been women, from the groundbreaking sociological studies of Deena Weinstein and Donna Gaines, to the recent ethnographic work of Emma Baulch. This article provides a preliminary investigation of this historical phenomenon and what it can reveal about the ever complex, constantly changing relationship between gender and power in metal.     

Heavy Genealogy: Mapping the Currents,Contraflows and Conflicts of the Emergent Field of Metal Studies, 1978-2010

What is metal studies? How can we define and characterize it? How has it emerged as a body of academic enquiry? What are its dominant disciplinary strands, theoretical concepts and preferred methodologies? Which studies have claimed most attention, defined the goals of scholarship, typical research strategies and values? How has the claim for the legitimacy or symbolic value of metal scholarship been achieved (if it has): over time and through gradual acceptance or through conflict and contestation? How can this process of formation, or strategy of legitimation, be mapped, examined and interrogated and which methods of historical, institutional and cultural analysis are best suited to this task? Working with the most complete bibliography to date of published research on heavy metal, music and culture (the MSBD), this article employs Foucault’s archaeological “method” to examine the institutional, cultural and political contexts and conflicts that inform the genealogy of this scholarship. Such analysis reveals a formative, largely negative account of heavy metal to be found in the “sociology of rock”; a large volume of psychology work, examining heavy metal music preference as an indicator of youth risk, deviance and delinquency; sociological work on youth and deviancy critical of the values of this research and its links to social policy and politics; culminating in the work of Weinstein and Walser, who advocate a perspective sympathetic to the values of heavy metal fans themselves. Following Bourdieu, I interpret such symbolic strategies as claims for expertise within the academic field that are high or low in symbolic capital to the extent they can attain disciplinary autonomy. I then go on to examine the most recent strands of research, within cultural studies and ethnomusicology, concerned with the global metal music diaspora, and consider to what extent such work is constitutive of a coherent subfield of metal studies that can be distinguished from earlier work and what the implications of this might be.     

The Price of Rebellion: Gender Boundaries in the Death Metal Scene

This article examines women’s involvement in the male-dominated death metal scene and illustrates the boundaries to their participation in the scene as equals. Interviews with female fans of death metal reveal an awareness of the sexist practices of the scene, as well as a willingness to tolerate such practices. The author discusses the attitudes and behaviors of female fans in this context using social exchange theory and argues that while women derive empowerment from death metal, they do so at the cost of conformity to its androcentric culture.     

Three profiles of heavy metal fans: A taste for sensation and a subculture of alienation

Profiles of three fans of heavy metal music are presented, in order to examine the definition and boundaries of the heavy metal subculture. It is suggested on the basis of these profiles that a high level of sensation seeking can lead to a liking for heavy metal music, because the music provides such high-intensity sensation. However, fans become part of thesubculture of heavy metal music only to the extent that their high sensation seeking is combined with alienation. Although all three people profiled enjoyed the high sensation qualities of the music, their involvement in the subculture varied according to the depth of their alienation. Jack, deeply alienated, was deeply committed to the subculture. Brian's alienation was moderate, and his involvement in the subculture was moderate as well. Marvin was not alienated in the least, and was essentially outside the subculture.     

Heavy metal in Turkey: Tracking the tensions of democratization in the 1990s

Music, as a form of public discourse, invariably becomes a social science field that is considered more in the postmodern era when the boundaries are blurred. This study examines the political and cultural links between the emergence of the heavy metal genre and Turkish democracy. There are correlations between the prevalence of heavy metal in Turkey and the country's social and political transition in the 1990s and the search for a new path. The main argument here is that, among the country's tense democratization efforts and social problems, the heavy metal genre also indirectly carries the distinct traces of a different political search for the youth of the 1990s, although not directly. Democratic politics is a process established by daily life with the direct influence of societal interactions, and Turkish politics, and cultural life, in this case, heavy metal, include important notions in this remarkable manner. The main point symbolized by metal music in Turkey was its lyrical and artistic ability to express different points of view loudly enough against the uniform religious and nationalist culture that could be offensive, while other mainstream ranges such as pop and arabesque music didn't mind this issue.     

Gender,Field, and Habitus: How Gendered Dispositions Reproduce Fields of Cultural Production

Bourdieu argues that fields of action produce a specific habitus in participants, and views this specific habitus as a mechanism through which the field is reproduced. Although Bourdieu acknowledges the habitus as gendered, he does not theorize gender as part of the mutually constitutive relationship between field and habitus. Using evidence from two cultural fields, the Toronto heavy metal and folk music scenes, I show that gender is central to the process through which field and habitus sustain each other. The metal field produces a “metalhead habitus” that privileges gender performances centered on individual dominance and status competition. In contrast, the “folkie habitus” encourages gender performances centered on caring, emotional relations with others, and community‐building. These differently gendered habitus support different working conventions: music production occurs largely through volunteer‐based nonprofit organizations in the folk field, and individual entrepreneurship in the metal field. The gendered habitus also supports different stylistic conventions: guitar virtuosity in the metal field, and participatory music‐making in folk. Applying a gendered lens to the field–habitus relationship clarifies the mechanisms through which cultural fields shape individual action, and the mechanisms through which cultural fields are reproduced and maintained.     

Allometry and photosynthetic capacity of poplar (Populus deltoides) along a metal contamination gradient in an urban brownfield

The value of urban green space has become an increasingly controversial issue. In particular, development of novel vegetative assemblages on vacant lands may have many formerly unrecognized benefits. However, questions remain regarding the functional impairment of these assemblages due to degraded soils. We investigated the effects of elevated concentrations of soil metals on allometry and photosynthetic capacity of naturally colonized poplars (Populus deltoides Michx.) growing at Liberty State Park, New Jersey. We found that allometries of harvested trees did not differ significantly between the low metal load (LML) and high metal load (HML) sites suggesting that metal contamination did not negatively affect carbon allocation patterns of the target species. Likewise, photosynthetic parameters did not differ significantly between the LML and HML sites, suggesting that soil metal contamination did not negatively affect photosynthetic capacity. However, trees from the LML site were significantly younger for a given size than trees from the HML site. Trees from the medium metal load site (MML) differed significantly in allometry and photosynthetic parameters from the other two sites suggesting other edaphic and ecological factors are a stronger driver for carbon allocation patterns and photosynthetic capacity in these trees. Taken together, this research suggests that sapling establishment and growth may be impaired by heavy metals and that trees in HML sites may incur more maintenance costs than trees in LML sites. However, given enough time, poplars can provide considerable rehabilitation of urban brownfields, particularly those that exhibit soil metal contamination.     

Gender and Performance Capital among Local Musicians

This article extends Bourdieu’s field theory to explain how learning spaces in the Toronto folk and metal scenes create gendered access to a field-specific form of cultural capital: performance capital, or the instrumental and interpersonal skills required to perform music. Folk musicians develop performance capital in open-access spaces, such as workshops and open stages at local folk clubs, while metal musicians learn in private spaces such as garages, basements, and rented rehearsal rooms. Folk’s learning spaces are open to all aspiring musicians, while access to heavy metal’s learning spaces relies on social networks from which women are often excluded. These different processes of capital development can lead to greater or lesser opportunities for women to become cultural producers: In Toronto, women make up approximately five percent of heavy metal musicians, but almost half of practicing folk musicians.     

Building community online and on the trail: communication,coordination, and trust among mountain bikers

The affordances of new information and communication technologies (ICTs) have altered the ways that communities emerge, interact, and organize, creating possibilities for new forms of interaction. Using a case study of the mountain biking community, this paper examines the impact of ICTs on community bonds and boundaries. Based on 60 intensive interviews in North America, survey results from 2363 mountain bikers around the world, and email exchanges with an addition 98 of the survey respondents, the findings suggest several ways that online and in-person communication intersect to blur the distinction between strong and weak ties, make the boundaries of the community more porous, and accelerate the development of trust between members.