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941.
The coliquefaction of coal and polystyrene (PS) in supercritical water (SCW) was carried out in a 50-mL batch stainless steel autoclave reactor, and the effects of the polymer ratio by weight (10–40%), reaction temperature (633.5–703.5 K), and reaction time (30–120 min) were investigated. The main products were analyzed qualitatively by Fourier transform infrared spectroscopy and high-performance liquid chromatography. The results show that polystyrene stimulates coal liquefaction as a hydrogen donor, and the synergistic effects during coliquefaction in SCW were confirmed. The conversion reached a maximum of 62.26% after 60 min at 673.5 K. The phase behavior during coliquefaction was observed in a fused silica capillary reactor using a combined microscope and video recorder system.  相似文献   
942.
In this study, two different versions of the Soil and Water Assessment Tool (SWAT) model were used to simulate the hydrology and biogeochemical response of the Cannonsville Reservoir watershed, in New York. The first version distributes overland flow in ways that are consistent with variable source area (VSA) hydrology driven by saturation excess runoff, whereas the second version is the standard version of SWAT. These two models were each calibrated for streamflow (Flow), particulate phosphorus (PP), total dissolved phosphorus (TDP), and sediment (Sed) against measured data from the 1,200 km2 Cannonsville watershed. The standard version of the model yielded an r2 between the measured and simulated data of 0.85, 0.73, 0.70, and 0.72 for Flow, Sed, TDP, and PP, respectively. The VSA version yielded an r2 of 0.84, 0.69, 0.72, and 0.53 for Flow, Sed, TDP, and PP, respectively. The two models were then used to determine the maximum upper bound on the reduction in phosphorus loading by removing all of the corn in the watershed. The average reductions between the two models were 65 and 37% for PP and TDP, respectively. The VSA version was also used to estimate the effect of moving corn land in the watershed from the wettest, most runoff prone areas to the driest, least runoff prone areas, which cannot be done directly with the standard SWAT model.  相似文献   
943.
Culturomics is emerging as an important field within science, as a way to measure attitudes and beliefs and their dynamics across time and space via quantitative analysis of digitized data from literature, news, film, social media, and more. Sentiment analysis is a culturomics tool that, within the last decade, has provided a means to quantify the polarity of attitudes expressed within various media. Conservation science is a crisis discipline; therefore, accurate and effective communication are paramount. We investigated how conservation scientists communicate their findings through scientific journal articles. We analyzed 15,001 abstracts from articles published from 1998 to 2017 in 6 conservation-focused journals selected based on indexing in scientific databases. Articles were categorized by year, focal taxa, and the conservation status of the focal species. We calculated mean sentiment score for each abstract (mean adjusted z score) based on 4 lexicons (Jockers-Rinker, National Research Council, Bing, and AFINN). We found a significant positive annual trend in the sentiment scores of articles. We also observed a significant trend toward increasing negativity along the spectrum of conservation status categories (i.e., from least concern to extinct). There were some clear differences in the sentiments with which research on different taxa was reported, however. For example, abstracts mentioning lobe finned fishes tended to have high sentiment scores, which could be related to the rediscovery of the coelacanth driving a positive narrative. Contrastingly, abstracts mentioning elasmobranchs had low scores, possibly reflecting the negative sentiment score associated with the word shark. Sentiment analysis has applications in science, especially as it pertains to conservation psychology, and we suggest a new science-based lexicon be developed specifically for the field of conservation.  相似文献   
944.
Leaders' perceptions of their teams are critical sources of contextual social information influencing leadership behaviors. In this paper, we extend affect-as-social-information theory to understand how and why team helping behaviors predict leaders' mistreatment of their teams in the form of abusive supervision and positive leader behavior in the form of empowering leadership, both through leaders' perceptions of team positive affective tone. In addition, based on social information processing, we examine the cue of leaders' perceptions of team task performance as a factor that helps us understand when the relationship between positive affective tone and leadership behaviors may be attenuated. In two text-based scenario studies, a video-based scenario study, and a multisource field study, we found evidence that team helping behavior is antecedent to abusive and empowering leadership behaviors and that this relationship is fully mediated by leaders' perceptions of team positive affective tone. Moreover, our results support team task performance as a factor that decreases the degree to which affective tone is related to abusive supervision. We discuss our findings as a caution to scholars' assumptions about the directionality of leader-team influence, emphasizing the need to acknowledge upward effects in workplace mistreatment research in the leader–team relationship.  相似文献   
945.
中国已经步入"互联网+"时代,再生资源行业也不例外。针对再生资源回收和电子商务的特点,借鉴国内相关成功案例,结合苏州市再生资源回收体系的现状,可以在苏州建设网络平台开展再生资源线上线下交易,并进一步对平台的流程、模块和一些重要问题进行了设计和分析。  相似文献   
946.
According to the risk management characteristics and the actual needs of safety production in coal mine, we thoroughly analyze the system of risk management method in coal mine and implement it in Geting Coal Mine. The system manages and controls the potential accident risks, hazard sources and human behavior risks. On this basis, the system of workers’ safety behavior control technology in coal mine is further studied, the “three disobeying” is classified and managed, the “three disobeying” database and safety countermeasures database are established, and the application software - the system of risk management and safety countermeasures optimization in coal mine based on B/S mode is developed and applied, which uses intranet to analyze and supervise the “three disobeying”, publish early-warning information, optimize management and control countermeasures; at the same time, the important prompting messages can be automatically sent to the mobile phones of relevant managers and the person in charge through public communication system in order to improve the real time capability and effectiveness of unsafe behavior control. The technological system and application software implemented in Geting Coal Mine has achieved good results.  相似文献   
947.
Conservation goals at the start of the 21st century reflect a combination of contrasting ideas. Ideal nature is something that is historically intact but also futuristically flexible. Ideal nature is independent from humans, but also, because of the pervasiveness of human impacts, only able to reach expression through human management. These tensions emerge in current management rationales because scientists and managers are struggling to accommodate old and new scientific and cultural thinking, while also maintaining legal mandates from the past and commitments to preservation of individual species in particular places under the stresses of global change. Common management goals (such as integrity, wilderness, resilience), whether they are forward looking and focused on sustainability and change, or backward looking and focused on the persistence and restoration of historic states, tend to create essentialisms about how ecosystems should be. These essentialisms limit the options of managers to accommodate the dynamic, and often novel, response of ecosystems to global change. Essentialisms emerge because there is a tight conceptual coupling of place and historical species composition as an indicator of naturalness (e.g., normal, healthy, independent from humans). Given that change is increasingly the norm and ecosystems evolve in response, the focus on idealized ecosystem states is increasingly unwise and unattainable. To provide more open‐ended goals, we propose greater attention be paid to the characteristics of management intervention. We suggest that the way we interact with other species in management and the extent to which those interactions reflect the interactions among other biotic organisms, and also reflect our conservation virtues (e.g., humility, respect), influences our ability to cultivate naturalness on the landscape. We call this goal a natural practice (NP) and propose it as a framework for prioritizing and formulating how, when, and where to intervene in this period of rapid change. Desarrollo de una Práctica Natural para Adaptar Objetivos de Conservación al Cambio Global  相似文献   
948.
949.
Fatty acid biomarkers and stable isotope signatures were used to identify the sources of particulate and sedimentary organic matter and its input into the food web through the dominant consumer within the mangrove-dominated Rufiji estuary, Tanzania. Specific fatty acids were used to identify the preferred basal sources of dominant fauna (i.e. filter feeder bivalves, snails, crabs, shrimps, and three fish species), and their presence in the water and sediment samples in the estuary. Both fatty acid and stable isotope results revealed that food web in the Rufiji estuary depended on a variety of carbon sources (mangroves, allochthonous terrestrial inputs, macroalgae, and phytoplankton), contributing to a different degree into the diets of primary consumers and members of near-shore fish, but none of them were obligatory for the survival of these species. The δ15N values of major primary producers and consumers/predators revealed a trend for δ15N enrichment with increasing trophic level. The ratio of docosahexaenoic acid to eicosapentaenoic acid (DHA:EPA) decreased from pelagic to benthic feeding fish. This indicated that fish with different feeding modes derived their fatty acids from different primary sources of nutrition, and suggested that the DHA:EPA ratio may be a useful indicator of feeding mode.  相似文献   
950.
汽车共享作为中国新兴的可持续交通方式,如何成功的使消费者接受和使用,是研究的关键挑战。本文基于UTAUT2模型,选择上海市居民作为调查对象,发现价格价值对行为意向影响最大,其次为享乐动机、努力期望、绩效期望和便利条件,社群影响对行为意向影响不显著;行为意向和便利条件对使用行为有显著正面影响,便利条件对使用行为影响更大。进而,使用个人特征为调节变量(是否有私家车、网约车经验和婚姻状况)验证对模型路径的影响,绩效期望对行为意向的影响受到是否有车、网约车经验和婚姻状况三个因素的调节,无车、无网约车经验与未婚的受访者调节效应更强;便利条件对行为意向和使用行为的影响同时受到是否有车单个因素的调节,无车者的调节作用更强;价值价格对行为意向的影响受到婚姻状况的调节,未婚者的调节效应更强;行为意向对使用行为的影响受到是否有网约车经验的调节,无网约车经验的调节效应更强。基于汽车共享服务发展初期的市场调查,本文建议汽车共享企业应提前布局服务网络,扩大会员数量,宣传它与私家车相比的成本优势和共享的价值观,获得细分市场。  相似文献   
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