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11.
Recent observation of proximity effect [H.B. Heersche, P. Jarillo-Herrero, J.B. Oostinga, L.M.K. Vandersypen, and A.F. Morpurgo, Nature, bf 446 (2007) p. 05555.] has ignited interest in superconductivity in graphene and its derivatives. We consider Ca-intercalated graphene bilayer and argue that it is a superconductor, and likely with a sizeable T c . We find substantial and suggestive similarities between Ca-intercalated bilayer (C6CaC6), and CaC6, an established superconductor with T c = 11.5 K. In particular, the nearly free electron band, proven to be instrumental for superconductivity in intercalated graphites, does cross the chemical potential in (C6CaC6), despite the twice smaller doping level, satisfying the so-called “Cambridge criterion”. Calculated properties of zone-center phonons are very similar to those of CaC6. This suggests that the critical temperature would probably be on the same scale as in CaC6.  相似文献   
12.
Pankaj Jain 《Zygon》2019,54(4):826-836
Although Indic perspectives toward nature are now well documented, climate engineering discussions seem to still lack the views from Indic or other non‐Western sources. In this article, I will apply some of the Hindu and Jain concepts such as karma, nonviolence (Ahi?sā), humility (Vinaya), and renunciation (Sa?nyāsa) to analyze the two primary climate geoengineering strategies of solar radiation management (SRM) and carbon dioxide removal (CDR). I suggest that Indic philosophical and religious traditions such as Hinduism, Buddhism, and Jainism offer ethical concepts to call for humility in all acts of climate engineering leading to a favoring of CDR over SRM and a favoring of lifestyle changes (particularly vegetarianism) over both. I demonstrate these concepts by introducing the five great elements from the Hindu philosophy, two Hindu legends from Hindu mythology, the Indic ethical ideas of karma, renunciation, and humility, and the moral authority of Gandhi.  相似文献   
13.
Paul H. Carr 《Zygon》2018,53(2):443-461
What are we doing to our climate? Emissions from fossil fuel burning have raised carbon dioxide concentrations 35 percent higher than in the past millions of years. This increase is warming our planet via the greenhouse effect. What is climate change doing to and for us ? Dry regions are drier and wet ones wetter. Wildfires have increased threefold, hurricanes more violent, floods setting record heights, glaciers melting, and seas rising. Parts of Earth are increasingly uninhabitable. Climate change requires us to act as a global community. Climate justice enjoins emitters to pay the social‐environmental costs of fossil fuel burning. This would expedite green solar, wind, and next‐generation nuclear energy sources. Individuals should conserve resources, waste less food, and eat a plant‐rich diet.  相似文献   
14.
Emily E. Austin 《Zygon》2018,53(2):507-514
Climate change is a wicked problem with causes and consequences overlapping with other wicked problems and no single solution (Hulme 2015). For example, the frequent droughts associated with climate change exacerbate another major problem facing humanity as we enter the Anthropocene: how to produce adequate food to feed a growing population without increasing pollution or “more food with low pollution (MoFoLoPo)” (Davidson et al. 2015). Soils represent an intersection of these two wicked problems, because they are integral to food production through agriculture and also are an important component of global climate models. Recent focus in the field of soil carbon cycling has facilitated a transformation in our understanding of the processes that control this important resource. This understanding is critical to responding to both wicked problems.  相似文献   
15.
A large body of research has suggested that anxiety sensitivity (AS) acts as a specific vulnerability factor in the development of anxiety pathology. More recently, attention has turned to the etiology of AS per se. The present study tested several related etiological hypotheses derived from Expectancy theory. S. Reiss and R. J. McNally (1985) originally proposed that greater physiological reactivity would increase risk for developing heightened AS. Reactive individuals are believed to have greater opportunity to perceive unpleasant bodily perturbations, thereby increasing the likelihood that concerns and fears could be attached to the sensations. Nonclinical participants (N = 86) completed physical (e.g., orthostatic) and biological (e.g., 35% CO2) challenges and a heart beat perception task. AS was not related to heart beat perception but was related to greater tonic heart rate and greater diastolic blood pressure (DBP) reactivity to both the challenges. Higher DBP and higher heart beat accuracy interacted to predict higher AS.  相似文献   
16.
The inhalation of 7.5% CO2 has been shown to induce cognitive effects similar to anxiety. Sixteen healthy participants (14 male; mean age 25.6 years) inhaled either a mixture of 7.5% CO2 gas or air while playing a group combat computer game. Participants reported greater feelings of anxiety and fired fewer bullets when inhaling CO2 compared with air, indicating CO2-induced anxiety may improve efficiency without task-related decrements. Being able to induce controlled and measured anxiety in group situations by CO2 inhalation may be a useful technique when evaluating response to stressful situations, such as combat, in simulators or real-life scenarios.  相似文献   
17.
急性一氧化碳(carbonmonoxide,CO)中毒是中美最常见的意外中毒原因之一。高压氧能促进碳氧血红蛋白解离,加速体内CO排出,明显缩短CO半清除时间,是治疗急性CO中毒的一种重要治疗方法。比较中美现有急性CO中毒治疗指南及推荐意见。发现其中在高压氧治疗应用的适应证、具体方案、治疗费用等方面有很大差异。我们对此差异进行比较分析,为临床治疗及科研提供参考,也对通过进一步研究以充分证实高压氧治疗急性CO中毒的有效性,制订高压氧治疗最佳方案提出展望。  相似文献   
18.
Roll, Higgins, and Badger (1996) used a carbon monoxide (CO) detector to determine whether participants smoked in a smoking-cessation study. We sought to replicate their work with adults with mild mental retardation. However, verbal instructions were inadequate to establish stable exhalations of sufficient durations for reliable and accurate CO evaluation. This report describes a shaping procedure that enabled 3 of 4 participants to achieve 20-s exhalation durations.  相似文献   
19.
Carbon segregation in Cr8Mo2SiV tool steel after common heat treatment (CHT) and deep cryogenic treatment (DCT) has been investigated by X-ray diffraction (XRD), transmission electron microscopy (TEM) extraction replica and three-dimensional atom probe (3DAP) tests. The XRD results show that most of the retained austenite transformed to martensite after DCT. The TEM results confirm the transformation of blocky retained austenite to twin martensite during DCT. The 3DAP results reveal the segregation of carbon atoms and the maximum carbon fraction in carbon-rich regions increases after DCT. The peak carbon concentration in carbon-rich regions of SDC99 steel after CHT and DCT are 8 at. % and 15 at. %, respectively. The segregated carbon atoms grew into nuclei for nanoscale carbides precipitation on subsequent tempering.  相似文献   
20.
Two global initiatives, the Genographic Project and the Carbon Lottery, share an ambition to make abstract, global processes—human evolution and climate change—comprehensible and engaging to non-specialists. Despite their differences, they both do so by means of self-objectifications that scale up the selves of participants and scale down complex, spatio-temporal models of human–world relations. The author’s auto-ethnographic experiences in both initiatives illustrate how carbon calculators and personalised genomics involve a pragmatics of scale that evaluates and compares users on the basis of their relative expression of, or deviation from, a standard. Furthermore, this is not based on actual resources that participants do or do not possess, but on forms of capitalist exchange that underwrite carbon trading and population genomics, as experts and corporations make intellectual property derived from purportedly rare DNA and sustainable practices, which are typically indigenous and non-western. In fact, the global inequalities that make possible transactions in carbon offsets and genetic ancestry are obscured from view. As a result, though initiatives like the Genographic Project and Carbon Lottery may provide comprehensible self-objectifications, they potentially make the world more unequal in the process.  相似文献   
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