环境学实验课程线上线下混合教学模式研究

基于环境学实验课程的特点,结合高校课程改革的实际情况,探讨了环境学实验课程线上线下混合教学模式的设计,调查分析了混合教学模式改革的课程教学效果,以期提升高校环境学实验课程的教学质量,为相关实验课程教学改革提供借鉴。

《水域环境学》实验教学体系的改革与创新

针对传统的水域环境学实验仅作为理论课程教学的延续和补充,其教学仅限于课堂和简单的验证性实验,对水域环境学实验的教学体系、实验教学方法、实验教学手段和实现绿色实验的教学理念等方面进行改革和探讨。创建了"一体化、多层次"的实验教学体系,即在课堂实验和实验室开放基础上,开展教学实习、专业生产实习和毕业论文等环节,形成理论与实验教学并重的教学格局,培养学生主动学习的精神和创新能力,为促进水域环境学实验教学发展和创新型人才培养提供参考。

Passivity Degradation of Nuclear Materials in Reduced Sulfur Environments:A Review

This paper reviews sulfur-induced passivity degradation of nuclear materials with emphasis on steam generator(SG)alloys. The state of arts on this topic concerning thermodynamic calculation and experimental data has been reviewed. Thermodynamic calculation results indicate that the distribution of sulfur species strongly depends on p H and temperature. Experimental data show that solution p H, temperature and solution chemistries can significantly affect the electrochemical behaviors of SG materials and the underlying degradation mechanisms. Some issues when conducting corrosion tests at high temperature should be paid attention to, such as the dissolution of the autoclave, which may affect the facticity of the experimental results.

Impact of an active educational video game on children's motivation,science knowledge, and physical activity

Background： Active educational video games （AVGs） appear to have a positive effect on elementary school students＇ motivation leading to enhanced learning outcomes. The purpose of this study was to identify the effectiveness of an AVG on elementary school students＇ science knowledge learning, physical activity （PA） level, and interest-based motivation. Methods： In this randomized controlled study, 53 elementary school students were assigned to an experimental condition or a comparison condition. The experimental condition provided an AVG learning environment, whereas the comparison condition was based on sedentary educational video games. Results： The results of repeated measures analysis of variance （ANOVA） on the knowledge test showed that students in both groups performed better on the post-test than they did on the pre-test （p 〈 0.001, η2 = 0.486）, and their post-test scores did not differ significantly. The experimental condition provided a more active environment since the students＇ average heart rates （HRs） were in the Target-Heart-Rate-Zone （HR = 134 bpm）, which was significantly higher than the average HR （103 bpm） from the comparison condition （t = 7.212, p 〈 0.001）. Students in the experimental condition perceived a higher level of situational interest than their counterparts in the comparison group （p 〈 0.01, and η2 = 0.301）. Conclusion： These results suggest that AVGs benefit children more in terms of PA and motivation than traditional video games by providing an enjoyable learning experience and sufficient PA.

Microhabitat use by white-footed mice Peromyscus leucopus in forested and old-field habitats occupied by Morrow's honeysuckle Lonicera morrowii

We quantified microhabitat use by white-footed mice Peromyscus leucopus in forest and old-field habitats occupied by Morrow＇ s honeysuckle Lonicera morrowii, an invasive exotic shrub imported from Japan. Microhabitat characteristics were compared between trails used by mice （ n = 124） and randomly selected trails （ n = 127） in 4 study plots located at Fort Necessity National Battlefield, Farmington, Pennsylvania, USA. We compared 10 mierohabitat variables between used and random trails using non-metric multidimensional scaling （NMDS） and classification and regression tree （CART） analysis. Trails used by mice were statistically different from randomly selected trails in both forested plots （ P 〈 0. 008） and old-field plots （ P 〈 0. 001 ）. In the forested plots, trails of white-footed mice were more often associated with a greater percent cover （% cover） of coarse woody debris （CWD） than were randomly selected trails. In the old-field plots, mouse trails were commonly characterized by having a lower % cover of exotic herbaceous vegetation, a greater % cover of shrubs, and a greater % cover of Morrow＇ s honeysuckle than randomly selected trails. Our study indicates that white-footed mice do not move randomly and prefer areas of high structural complexity, thereby showing significant microhabitat preference. The preference of white-footed mice for areas with a relatively high percent cover of Morrow＇s honeysuckle could 1 ） be a factor in the aggressive nature of the exotic honeysuckle shrub＇s spread throughout the Battlefield or 2） cause the shrub to spread even faster into adjacent areas not yet occupied by Morrow＇ s honeysuckle

Effect of galvanic contact on the flotability of galena in the presence and absence of a collector

In this paper,the effect of various electrochemical environments in the galena flotation is investigated.The electrochemical environments consisted of a ball mill for grinding of galena ore and a Denver flotation cell for flotation of galena in the laboratory scale.In order to achieve the maximum recovery with sodium hyposulfite,the concentrations of 0.06 and 0.12 M of air and nitrogen gases have been used to control the pulp potential in the Denver flotation cell.The galena sample was from the ''Era mine'' which is located in the Kiyasar area,north of Iran.This mine contains:Galena(PbS) at least 22%,Fluorite(CaF 2) 73.37%,Quartz(SiO 2) 2.54% and other minerals such as Cerussite(PbCO 3) and Kaolinite(Al 2 Si 2 O 5(OH) 4).Flotation of Galena was conducted in a 0.12 M of sodium hyposulfite solution.It was found that the amount of recovery by this process was 85% and 63% in the presence and absence of potassium amyl xanthate(KAX) and at an estimated potential of 280 to 350 mV respectively while the recovery was 70% and 52% at an approximate potential of 175 to 210 mV in water in the presence and absence of collector(KAX).

Promoting Iranian EFL Teachers＇ Attitudes Toward Self-Assessment Through Using Computer Technology

The application of technology in language classrooms has recently become commonplace. However, a very important set of variables, such as the teacher＇s attitudes toward the effective uses of computers in the classroom and SA （self-assessment）--on the part of the students--have been overlooked in EFL （English as a foreign language） classrooms. The goals of this study are defining teacher beliefs, discussing the relationship between teachers＇ beliefs about the application of SA and integration of computer technology, reviewing teachers＇ beliefs and computer knowledge, elaborating teachers＇ beliefs and computer technology training. To this end, a total number of 68 EFL teachers participated in this study. Participants of the experimental group included the teachers who had already been trained how to use and apply computer in their teaching, and the participants of the experimental group included the teachers who were teaching in traditional learning and teaching environments with the least access to and employ of computer. Comparing the participants in the experimental and control groups＇ attitude questionnaire showed that Iranian EFL teachers＇ positive attitudes toward SA will improve if they are engaged in computer supported learning and teaching environments

Due Diligence in Mergers and Acquisitions in Emerging Markets： Evaluated Risk Factors From the Academic and Practical View

The obviously ever increasing number of corporate acquisitions in recent decades has improved the general knowledge and awareness of due diligence for both the industry and research. In the current challenging business environment, acquisitions face a higher degree of risk profiles, especially cross-border acquisitions in the emerging markets. Conducting a thorough due diligence investigation in the context of an acquisition is more important now than ever. In a broad analysis, this paper researches the key risk factors in the acquisition process and their assessment within a due diligence audit in the acquisition phase. The task of this paper is to match the academic and practical view in order to give a more complete understanding of risk factors to be covered in due diligence audit. The starting point is the research of academic findings which basically concentrate on common approaches considering financial, legal, commercial, and some other issues in domestic acquisitions and in developed countries. In contrast, this paper considers risk factors in cross-border and emerging markets transactions. In addition, a number of business consultants publish studies based on surveys on this topic which reflect typical risk factors based on experience of their customers being involved in cross-border acquisitions. Their risk assessment consists of specific regulatory, political, and other factors, which may lead to commercial and reputational impediments in cross-border acquisitions. The outcome of the comparison is a comprehended list of evaluated risk factors, whereby the academic findings are complemented and supported by the practical experience in the business consultant＇s studies. Moreover, the practical approach points to the fact that due diligence scope needs to be suited to the dynamics of the markets. The comparison and the comprehended list of evaluated risk factors call for a more integrated system of due diligence and show herein the research deficit. Hence, the novelty is the compendium of evaluated risk factors which should be assessed in the pre-acquisition phase. The originality of the paper is given by a unique analysis of academic work about acquisition due diligence literature and consultant studies from anonymized practical experience based on insider information.

The International Research Group in Geophysics Europe Africa： A Laboratory without Borders in the Earth Science and Environment

It was in 1995 that, at the end of the international project IEEY （International Equatorial Electrojet Year）, African and European scientists decided to create the IRGGEA （International Group in Geophysics Europe Africa） in order to pursue the scientific work started during the IEEY project, The main objective of IRGGEA was to introduce new fields of research in Africa and built teams of African scientists recognized at an international level in these new fields. To reach this goal, we developed days after days methods to manage smoothly a large network of scientists from developed and developing countries. After a short introduction on the field of research developed in the IRGGEA, we present the organization of the work based on sharing practices and the results obtained in terms of scientific publications and socio-cultural aspects as the increase of the number of women and positions for students in their countries. Such an experience is easy to reproduce.

Establishing and Evaluation of the Microgravity Level in the SJ-10 Recoverable Satellite

In order to fulfil the microgravity requirements for space experiments, improved technology for the microgravity environment is proposed, including that for raising the orbital altitude, optimizing the layout of the disturbance source, using IN-thrusters instead of 5 N-thrusters, etc. In addition, evaluation of the microgravity environment of the recoverable satellite was also conducted using on-orbit micro-vibration measurement, on-orbit experiment and data analysis technologies. The microgravity level of the SJ-l0 recoverable satellite in China is compared with the spacecraft used for carrying out space science experiments internationally. This paper describes the microgravity environment of the SJ- 10 recoverable satellite, and its importance for analysing space experimental results.

Water quality criteria research and progress

Water quality criteria (WQC) are threshold limits for pollutants or other hazard factors in the ambient water environment, which are based on scientific experiments and extrapolations. Until now, there is limited information available regarding the study of water quality criteria in China. It is imperative to launch national-level systematic WQC studies that focus on the regional characteristics of China and provide scientific support for the enactment or revision of water quality standards and environmental management. This article reviews the concept of WQC and discusses the methodology and global progress of WQC research. The article also summarizes the key scientific issues in WQC research, including species sensitivity distribution, toxicological endpoint selection, and models selection. Furthermore, we can adopt the derivation method used in the USA and divide WQC into acute and chronic criteria. Finally, considering the current status of WQC research in China, we point out important directions for future national studies, including the selection of native species and the comprehensive use of models.

Influence of extreme weather and meteorological anomalies on outbreaks of influenza A (H1N1)

Biological experiments and epidemiological evidence indicate that variations in environment have important effect on the occurrence and transmission of epidemic influenza.It is therefore important to understand the characteristic patterns of transmission for prevention of disease and reduction of disease burden.Based on case records,we analyzed the environmental characteristics including climate variables in Changsha,and then constructed a meteorological anomaly susceptive-infective-removal (SIR) model on the basis of the results of influenza A (H1N1) transmission.The results showed that the outbreak of influenza A (H1N1) in Changsha showed significant correlation with meteorological conditions;the spread of influenza was sensitive to meteorological anomalies,and that the outbreak of influenza A (H1N1) in Changsha was influenced by a combination of absolute humidity anomalous weather conditions,contact rates of the influenza patients and changes in population movements.These findings will provide helpful information regarding prevention strategies under different conditions,a fresh understanding of the emergence and re-emergence of influenza outbreaks,and a new perspective on the transmission dynamics of influenza.