超临界机组发生FAC的因素及相互关系分析

为了减轻因流动加速腐蚀(FAC)引起的锅炉结垢加速、汽水系统管道厚度减小甚至爆裂现象，对超临界机组发生流动加速腐蚀的机理及其主要影响因素进行了研究，并讨论了管壁内表面粗糙度、蒸汽含汽率、pH值、溶氧量对FAC的影响，以及温度与pH值、温度与流速、pH值与溶解氧量、溶解氧量与氢电导率等影响因素之间的相互作用关系，最后结合实际电厂的运行数据验证了分析结果。研究表明：减小工质流速、管壁粗糙度和氢电导率，增大给水的pH值和溶解氧含量可以使FAC的腐蚀速率减小，超临界加氧处理时pH值应在8.9～9.2之间，溶解氧量范围为45～100μg/L,氢电导率的期望值在0.1μS/cm以下。由于各影响因素之间的作用十分复杂，本文只给出了大致范围和趋势，并未给出准确数据。     

Transposable Elements and Stress in Vertebrates: An Overview

Since their identification as genomic regulatory elements, Transposable Elements (TEs) were considered, at first, molecular parasites and later as an important source of genetic diversity and regulatory innovations. In vertebrates in particular, TEs have been recognized as playing an important role in major evolutionary transitions and biodiversity. Moreover, in the last decade, a significant number of papers has been published highlighting a correlation between TE activity and exposition to environmental stresses and dietary factors. In this review we present an overview of the impact of TEs in vertebrate genomes, report the silencing mechanisms adopted by host genomes to regulate TE activity, and finally we explore the effects of environmental and dietary factor exposures on TE activity in mammals, which is the most studied group among vertebrates. The studies here reported evidence that several factors can induce changes in the epigenetic status of TEs and silencing mechanisms leading to their activation with consequent effects on the host genome. The study of TE can represent a future challenge for research for developing effective markers able to detect precocious epigenetic changes and prevent human diseases.     

涪陵地区茅三段热液白云岩展布影响因素分析

针对热液白云岩展布非均质性强的问题,开展基底断裂与茅三段沉积演化关系研究,分析断裂样式与白云岩分布关系,建立沉积演化模式,预测白云岩的分布。研究结果表明:茅三段可划分为5个小层,1~3小层为白云岩发育主要时期,4~5小层为台地均一化时期,不发育白云岩;15-1、15-2和16号基底断裂控制了早期“台-洼”相间的沉积地貌,断裂附近的地貌高部位为生屑滩发育有利部位,为白云岩的发育提供物质基础;15-1、15-2号基底断裂样式为花状,周边生屑滩白云石化程度高,为白云岩发育最有利区;16号基底断裂为直立状,附近白云石化发育程度较低,为白云岩发育较有利区。研究成果可为热液白云岩领域的进一步勘探提供指导依据。     

高职院校学生创业意向影响因素研究

采取简单随机方法,从菏泽家政职业学院各个系随机选取6个班,以笔者自拟的调查问卷对该6个班的全体学生进行问卷调查,并采用二元logistic回归分析对问卷调查的结果进行多因素分析,最后得出结论,性别、所学专业、专业知识和技能、家人态度、创业资金来源、他人影响对高职院校学生创业意向的影响不显著,而内控制源、创业能效感、风险忍耐度、政府支持对高职院校学生创业意向有显著影响。     

北京市郊玉米质量安全风险因子及影响因素分析

以北京郊区10个农户的玉米种植地为研究对象,扦取种植期土壤样品、扬花期花穗样品、收获期及不同储藏时期的玉米样品,检测菌相、带菌量和真菌毒素等。结果表明,玉米产后整个自然晾晒储藏期间,储藏前期(产后一个月内)的发霉风险最高,其中镰刀菌属一直是优势菌群,其产生的毒素主要包括脱氧雪腐镰刀菌烯醇(DON)、玉米赤霉烯酮(ZEN)和伏马菌素(FB1、FB2),检出率分别为100%、95%和93%,且DON和ZEN在储藏期的超标率均大于40%,而其他毒素,如AFBs、OTA、ST、T-2、HT-2等均未检出。另外,采用高通量测序技术分析了土壤和花穗样品中真菌多样性与农艺因素的关系,发现,种植方式(清种/兼做)、灌溉情况、上季秸秆处理方式等因素会影响玉米植株污染真菌的种类和数量,进而导致玉米籽粒真菌毒素的污染水平出现差异。     

Muddling between science and engineering: an epistemic strategy for developing human factors and ergonomics as a hybrid discipline

Human Factors and Ergonomics (HFE) recognises itself as a design-driven, systemic and scientific discipline geared towards well-being and performance. Being a scientific discipline and design-oriented requires that the epistemic basis of science and design/engineering be fully comprehended. In interdisciplinary research where these two viewpoints meet, there are often dilemmas posed in terms of knowledge construction and labelling of activity. Therefore, this article scrutinises these two orientations and addresses the differences and commonalities, using case studies from engineering and psychological science (both constituents of HFE). Based on these insights, a way forward is suggested in terms of (1) a reflexive engagement with epistemic concepts and methods; (2) finding a conceptual space for balancing and bridging the science-engineering divide; (3) comprehending ‘design-thinking/design knowledge’ and not treating it as an application of science; (4) providing emphasis on problem formulation and practices of HFE focusing on developing them in systemic terms.