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1.
在多晶硅太阳能电池的生产过程中, 金刚线切割技术(Diamond wire sawn, DWS)具有切割速度快、精度高、原材料损耗少等优点, 受到了广泛关注。金刚线切割多晶硅表面形成的损伤层较浅, 与传统的酸腐蚀制绒技术无法匹配, 金属催化化学腐蚀法应运而生。金属催化化学腐蚀法制绒具有操作简单、结构可控且易形成高深宽比的绒面等优点, 具有广阔的应用前景。本文总结了不同类型的金属催化剂在制绒过程中的腐蚀机理及其形成的绒面结构, 深入分析和讨论了具有代表性的银、铜的单一及复合催化腐蚀过程及绒面结构和电池片性能。最后对金刚线切割多晶硅片表面的金属催化化学腐蚀法存在的问题进行了分析, 并展望了未来的研究方向。  相似文献   
2.
机器翻译译文质量估计(Quality Estimation,QE)是指在不需要人工参考译文的条件下,估计机器翻译系统产生的译文的质量,对机器翻译研究和应用具有很重要的价值。机器翻译译文质量估计经过最近几年的发展,取得了丰富的研究成果。该文首先介绍了机器翻译译文质量估计的背景与意义;然后详细介绍了句子级QE、单词级QE、文档级QE的具体任务目标、评价指标等内容,进一步概括了QE方法发展的三个阶段: 基于特征工程和机器学习的QE方法阶段,基于深度学习的QE方法阶段,融入预训练模型的QE方法阶段,并介绍了每一阶段中的代表性研究工作;最后分析了目前的研究现状及不足,并对未来QE方法的研究及发展方向进行了展望。  相似文献   
3.
《水科学与水工程》2022,15(1):29-39
In this article, current research findings of local scour at offshore windfarm monopile foundations are presented. The scour mechanisms and scour depth prediction formulas under different hydrodynamic conditions are summarized, including the current-only condition, wave-only condition, combined wave-current condition, and complex dynamic condition. Furthermore, this article analyzes the influencing factors on the basis of classical equations for predicting the equilibrium scour depth under specific conditions. The weakness of existing researches and future prospects are also discussed. It is suggested that future research shall focus on physical experiments under unsteady tidal currents or other complex loadings. The computational fluid dynamics-discrete element method and artificial intelligence technique are suggested being adopted to study the scour at offshore windfarm foundations.  相似文献   
4.
目的 对国内多感官设计的相关文献进行总结分析,探寻该领域的研究现状、热点与发展趋势,为今后多感官设计理论及实践研究提供参考。方法 基于文献计量分析法,以2005-2021年知网、万方、维普、超星及华艺数据库收录的741篇多感官设计文献为分析对象,采用CiteSpace、NoteExperss等软件对该领域文献的发表时间、载文期刊、高被引文献、作者、机构、  相似文献   
5.
BackgroundGluten- and lactose-free products are registering a sudden rise in the market, particularly among tolerant people, and this leads to consumer confusion and nutritional inadequacies. The number of studies around this trend has steadily increased in the last 10 years, as scholars from different disciplines have tried to rationalize consumers’ behaviours in these foods’ choice. However, the scientific debate appears fragmented and lacks an integrated view.ObjectivesWe conducted a systematic integrative review of consumers’ determinants of gluten-free and lactose-free consumption to frame the state of the art and research gaps.Methods45 English language articles reporting quantitative empirical studies ranging from 1971 and 2019 were analysed. First we categorized the consumption determinants in six factors applying the model proposed by Koster and Mojet, then we proposed a new integrated conceptualization inspired by Bronfenbrenner’s Transtheoretical Model. Moreover, differences and similarities between tolerant and intolerant consumers will be highlighted.ResultsResearch on intolerant consumers focused more on individuals’ determinants, in terms of awareness, trust, morality, and capability to read nutritional facts (as purchase facilitators); while studies targeting tolerant consumers focused more on objective product characteristics (with price and availability in supermarkets as barriers for consumption). In this target the subjective perspective has been studied only referring to the risk for developing psychological issues in the restrictive diet.ConclusionAs information is lacking in the scientific debate, we suggest for future research the integration of consumers’ subjective implicit levers to decipher free-from purchase behaviours.  相似文献   
6.
《Ceramics International》2022,48(14):19513-19526
Comprehensive control of processing techniques is primordial when fine-tuning the morphological features of titanium dioxide nanotube arrays (TNTs). This systematic review and meta-analysis compiled articles published from 2007 to date on the synthesis and growth mechanism of nanotubes fabricated via electrochemical anodization and evaluated the potential relationships between anodizing conditions and the resulting structures. Studies were gathered from the Science Direct online database, screened according to predefined criteria, and evaluated for their eligibility. Ninety-nine studies were assessed in the meta-analysis, 87 of them on tube length, 80 on tube diameter, and 33 on wall thickness. Multiple linear regression was performed to test if anodization parameters significantly predicted the resulting morphology of TiO2 nanotubular structures. Overall regression for the three responses was statistically significant (length: R2 = 0.487, p < 0.001; diameter: R2 = 0.899, p < 0.001; wall thickness: R2 = 0.792, p < 0.001). Applied potential was one of the main effects predicting all three responses (p < 0.001 in every model). Other important main predictors were anodizing time for tube length (p < 0.001), water percentage for tube diameter (p < 0.001) and ammonium fluoride (NH4F) concentration for wall thickness (p < 0.001).  相似文献   
7.
Crowdwork, a new form of digitally mediated employment and part of the so-called gig economy, has the capacity to change the nature of work organization and to provide strategic value to workers, job providers, and intermediary platform owners. However, because crowdwork is temporary, large-scale, distributed, and mediated, its governance remains a challenge that often casts a shadow over its strategic value. The objective of this paper is to shed light on the making of value-adding crowdwork arrangements. Specifically, the paper explores crowdwork platform governance mechanisms and the relationships between these mechanisms and organizational value creation. Building on a comprehensive review of the extant literature on governance and crowdwork, we construct an overarching conceptual model that integrates control system and coordination system as two complementary mechanisms that drive crowdwork platform governance effectiveness and the consequent job provider benefits. Furthermore, the model accentuates the role of the degree of centralization and the degree of routinization as critical moderators in crowdwork platform governance. Overall, the paper highlights the potential of crowdwork to contribute not only to inclusion, fair wages and flexible work arrangements for workers but also to organizations’ value and competitive edge.  相似文献   
8.
“民以食为天,食以安为先。”作为一个全球性问题,食品安全不仅影响每个人的健康水平与生活质量,更关乎整个国家的经济与发展。近年来,“毒奶粉”、“地沟油”、“染色馒头”、“毒豆芽”等频繁发作的食品安全恶性事件引起了社会的极大关注,也使人们对食品安全检测的需求进一步提高。而食物种类多样、成分复杂、及加工工艺繁琐等特点也为食品安全检测技术和方法带来了更大的难度和挑战。众多检测方式中,毛细管电泳(CE)以分析成本低、样品用量少、分离模式灵活多样、对环境污染小等优势被广泛应用。本文综述了2015年以来CE在食品安全检测中农药残留、兽药残留、多种食品添加剂、食品包装材料中双酚A和塑化剂等多个方面的分析应用,并对其未来的发展方向作了简要的展望。  相似文献   
9.
Z. T. Ai  A. K. Melikov 《Indoor air》2018,28(4):500-524
This article reviews past studies of airborne transmission between occupants in indoor environments, focusing on the spread of expiratory droplet nuclei from mouth/nose to mouth/nose for non‐specific diseases. Special attention is paid to summarizing what is known about the influential factors, the inappropriate simplifications of the thermofluid boundary conditions of thermal manikins, the challenges facing the available experimental techniques, and the limitations of available evaluation methods. Secondary issues are highlighted, and some new ways to improve our understanding of airborne transmission indoors are provided. The characteristics of airborne spread of expiratory droplet nuclei between occupants, which are influenced correlatively by both environmental and personal factors, were widely revealed under steady‐state conditions. Owing to the different boundary conditions used, some inconsistent findings on specific influential factors have been published. The available instrumentation was too slow to provide accurate concentration profiles for time‐dependent evaluations of events with obvious time characteristics, while computational fluid dynamics (CFD) studies were mainly performed in the framework of inherently steady Reynolds‐averaged Navier‐Stokes modeling. Future research needs in 3 areas are identified: the importance of the direction of indoor airflow patterns, the dynamics of airborne transmission, and the application of CFD simulations.  相似文献   
10.
Although the unprecedented prevalence of social media has infiltrated into international students’ daily trajectories and become an indispensable component of their intercultural communication, yet surprisingly few attempts have been implemented to systematically unpack how the innovative technology could play a role in these sojourners’ acculturation experiences and the consequences of migration and cross-cultural adaption. In order to address such research gap, the objective of this present article is to provide a review of academic, peer-reviewed journal studies that examined the potential effect of social media engagement on international university students’ acculturation process, coping strategies, and psychological adjustments during the period from 2010 to 2019. Moreover, building upon conceptualizations from new media and transcultural research literature, a conceptual framework was developed to classify the relevant studies for further analysis. Overall, these theories and studies synthesized in this paper emphasize the vital role of social media in the acculturation, coping behaviors and mental health for ethnic minorities in the host country. Additionally, certain dimensions of attitudes and behaviors through social media could exert the important influence on the psychological adaption. Therefore, conclusions of the research may assist to further inform practitioners who may encounter newcomers’ experiencing intercultural adjustments and psychological issues in the digital media age. Furthermore, this current review may also help educators determine certain barriers that have not been resolved in campus tactics which may influence the acculturation of sojourning populations.  相似文献   
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