The selenylation mechanism of luteolin was investigated using DFT.The calculation in-volved searching for transition states,validating the intrinsic reaction coordinates,computing the ther-modynamic parameters.The results show there are two pathways for the reaction.At molecular ratios of 2∶1 and 1∶1 for the reactants,the reaction yields P1 and P2,respectively.The apparent rate con-stants for each step were calculated at temperatures ranging from 273.15 K to 373.15 K using transition state theory.The minimum k2 from the step producing INT1 changes significantly with increasing tem-perature,which demonstrates that it is the rate-determining step,consistent with the thermodynamic mechanism.
张新科先生新著《文学经典的建构之路》对于史传作品的代表作品《史记》文学经典化作了理论性探讨，其“文学经典本质说”“建构路径多样说”“读者主体能动说”，是“史传作品文学经典化”的理论框架，使该论著成为研究“史传典籍何以文学经典化”的开先河之作，是史传作品文学经典建构理论性言说的典范。
将3阶广义Fibonacci和Lucas数的定义推广到3阶广义Fibonacci和Lucas复数,给出了3阶广义Fibonacci和Lucas复数之间的递推关系,研究了3阶广义Fibonacci和Lucas复数的生成函数和Binet型公式,同时,借助Binet型公式得到了Vajda,Catalan,Cassini以及d'Ocagne恒等式,这些恒等式的获得有助于研究广义Fibonacci和Lucas复数.
基于化学成分的分析,研究出古玻璃中高钾类型和铅钡类型的主导化学成分;根据主成分分析的结果,再进行AGG层次聚类分析将古玻璃分成若干亚类,得到古玻璃分类规律以及亚类划分规律中的判定化学成分及含量指标;分析了风化前后,主要化学成分所呈现的各自不同的变化规律,并对未知古玻璃品类及其风化情况进行了预测;最后基于决策树的预测算法对化学成分分析的结果进行验证.这些分析结果对于保护和进一步研究古玻璃有着重要意义.
韩邦奇的《正蒙拾遗》探讨了天人性道、修身处事、易学历史、天体历法、礼乐制度等多方面内容,体现了韩邦奇在理性抉择的前提下对张载思想的接受认同和开拓创新,是韩邦奇思想从"推阐朱子"到"归本横渠"转变的标志性作品,也是其思想学术表述较为集中的一部著作,更是明清关学能传述《正蒙》之学的重要代表作.韩邦奇"其学得关中嫡派"的地位,因其能传承关学"以礼为教"宗风和此书对张载思想的继承推阐而得以奠定.
Based on the teaching practice of the course“Academic writing”in university, this paper points out the defects and causes of the current teaching of academic writing, and gives the complete plan to optimize the courses through interactive teaching, to solve the problems of students. Moreover, it also points out the advantages of the course, compared with the present way.
Using the “online and offline blended teaching questionnaire” survey of 2,799 college students, content around the students’ learning attitudes and barriers, online learning behavior, cognitive and emotional attitude and learning style and validity, the results show that most students of online and offline blended teaching show overall open inclusive optimism, and can make good use of its advantages, but the traditional learning way of thinking and emphasis on low order knowledge acquisition behavior preference seriously hinders the online and offline blended efficient teaching. In the future,the online and offline blended teaching should focus on the cultivation of students’ core qualities such as critical thinking, innovative thinking, collaborative communication, multiple collaboration and problem solving ability.
Meta-studies are theoretical self-reflective studies after the development of disciplinary theories to a certain extent. The meta-analysis or meta-research of teaching theory in its logical form belongs to the scope of meta-research of teaching theory. Meta-research can conjure up a contingent picture of what teaching theory is, establish a profound direction for strengthening the guiding power of teaching theory in practice, and provide a self-reflective way to realize the ontological commitment of teaching theory. The meta-research of teaching theory contributes to the thinking tools for examining teaching theory and teaching, and conceals the conscious reflection of researchers and the ultimate resort to teaching theory. At present, the foreign meta-research on teaching theory, represented by the United States, mainly focuses on two categories: the nature and function of teaching theory and the application test and reflective criticism of teaching theory. The existing meta-research results in China mainly cover five categories of teaching theory: introduction and localization, development history,methodology, problems and their relationship with practice.
As an introductory course of computer, computer basic teaching is particularly important. In teaching, based on the concept of OBE education, appropriate teaching strategies should be adopted to promote students’ active participation in learning activities. Taking the stimulation of students’ subjectivity as the starting point, five implementation strategies are explored in this paper: role swap,benign competition, classroom interaction, reward and punishment mechanism, and perfect evaluation.
Based on the demands of exploring new economic growth points in the stage of high-quality development, exploring the coordinated development and regional differences of China’s cultural industry and tourism industry, selecting panel data of 31 provincial-level units from 2010 to2019, and using the entropy weight Topsis model to establish an evaluation index system The index weights were obtained and calculated to obtain the comprehensive scores and national average scores of the respective development levels of the cultural and tourism industries in each region. The degree of coupling coordination of 31 provinces and 7 major regions was calculated by means of the coupling coordination degree model. The research found that the development level of cultural industry and tourism industry has made obvious progress in 10 years, but there are obvious differences in time and space; the overall development level of the tourism industry is slightly ahead of the cultural industry,East China, and Northwest China leads the country This study provides factual basis and countermeasures for the high-quality development of the cultural tourism industry in various regions.
The great integration of Party history and ideological and political course is excellent for improving the quality of ideological and political education; also, the integration realizes the fundamental purpose of nurturing students for China and CPC. From the historical logic, the inheritance integration of Party history and ideological and political teaching highlights the excellent combination of Marxist theory and history education. From the theoretical logic, the combination of college Party history course and ideological and political course realizes the fusion of teaching aims and content. From the practical logic, in order to provide a reference for the advocacy of historical education, the accompaniment of Party history and ideological education systematically entails the construction of teaching teams, the reform of teaching methods, and improvement strategies of practical teaching.
Based on 157 microteaching video materials of normal university students, and using the modem mathematical statistics method, a quantitative analysis on the teaching effect of microteaching in this paper was conducted from the four aspects of the introduction section, i.e., duration, types,form and mode of the introduction in the microteaching process. The results show that one minute of the introduction duration（accounting for 10% of the total microteaching time） is the most suitable for the teaching effect, literary and academic introduction types are more effective than other types, and the type of teaching board could better reflect the special characteristics of geography. However, normal university students are faced with common problems of rigid connection between introduction and new knowledge, confusion of logic and language expression. Therefore, eight steps were proposed by strengthening the content organization and expression mode to effectively improve the introduction skills and teaching level for normal university students.
First, the loop gain of the classic Wen-bridge oscillator is analyzed, and then the loop is used as the loop of the T-T filter. Afterwards, a band-pass filter is designed and then a low-pass filter is designed by adding an integrator to realize the T-T filter. The filter uses only two integrated operational amplifiers. The circuit not only has low-pass and band-pass filtering, but also has a high Q value. It can also realize the orthogonal adjustment of pole frequency and quality factor. Two orthogonal sinusoidal signals can also be generated by adjusting the resistance. The computer simulation proves that the designed circuit is correct and effective.
When studying optimization problems in many fields, the problems of poor global search ability and slow convergence speed generally exist in the algorithm, which leads to the solution not reaching the optimum. An affine scale interior-point trust region algorithm for nonlinear equations is proposed. The objective minimization or objective maximization nonlinear equations are constructed,with the equality or inequality constraints set for the equations. Under the constraint conditions, the affine scale interior point trust region algorithm is used to obtain the optimal solution of the nonlinear equations. The proposed algorithm is applied to active power optimization, and the nonlinear equations are constructed with line loss minimization and voltage deviation minimization. Four constraint conditions are set for them, and the affine scale interpoint trust region algorithm is used to obtain the optimal solution. The experimental results show that compared with the adaptive particle swarm optimization algorithm, salps group algorithm and improved differential gray Wolf algorithm, the line loss and voltage deviation of the proposed algorithm are smaller under application, indicating that the affine scale interpoint trust region algorithm has better solution results and better search ability.
Modern genetics, founded in 1900 and introduced to China in 1913, has been slowly spreading in China. In 1922, modern genetics entered China’s higher education, opening a new page in the development of Chinese genetics, and a number of university genetics and biology textbooks systematically introduced modern genetic knowledge, which promoted young students’ comprehensive and in-depth understanding of the subject. During this period, domestic genetic research also made some achievements and was reflected in university textbooks. The dissemination of genetics in university textbooks not only contributes to the development of related disciplines, but also has referential significance for the editing of current textbooks.
A multifunctional compound, 4-[4-（4-propylbenzoyloxy） phenylazo] benzaldehyde,which possesses both liquid crystalline and photosensitive properties, was synthesized. The liquid crystalline phase properties of the compound were studied through differential scanning calorimetry（DSC）and polarized optical microscopy（POM）. The photo-transcis isomerization process of the compound after UV irradiation was studied with ultraviolet spectroscopy. The results show that the compound has typical liquid crystalline phase properties, and the temperature range of the liquid crystalline phase is wide; at the same time, the compound can undergo photoinduced trans cis isomerization, which is a first-order rate process in methanol or THF solution.
Planetary theory is one of the important contents of ancient mathematical astronomy in China. Since the Chunqiu period, Chinese astronomers have attached great importance to observing and recording of planetary positions. In the existing Chinese systems, the Triple Concordance System was the first one to give the algorithm for calculating the position of the planets. The planetary theory was simulated in the paper through a computer program and the accuracy of planetary calculations in the first 30 years of the Triple Concordance System was discussed. The results show that the maximum absolute error of Jupiter, Venus, Saturn, Mars and Mercury within 30 years of the early promulgation of the Triple Concordance System is 17.71°, 16.76°, 16.48°, 34.81° and 28.83° respectively. Further analysis shows that the first appearance of the planet, the structure of the planetary dynamic table and the length of the synodic period are the factors affecting the accuracy of the planetary calculation of the Triple Concordance System.
The university library is supposed to support course learning by serving teaching, learning and disciplinary construction with its information resources. Some means and methods for disciplinary theme service to assist course learning are analyzed in this paper by means of analyzing its content and showing its feature from the perspective of disciplinary theme service, and sums up some inspirations, wishing to be helpful for course learning support in university.
In order to ensure the land consolidation of Guanzhong Han and Tang Imperial Mausoleum area is to be carried out effectively, and promote the stable and increased grain yield, grain yield trend prediction regression model and fluctuation intensity regression model established by H-P filtering method and the improved C-D production function were used. The results show that: Grain production was in an overall downward trend of fluctuation on the whole, and showed the characteristics of large fluctuation—stable—large ups and downs in the fluctuation, with the highest fluctuation rate in2017, more than 20%. The scale of land consolidation had a certain negative impact on grain yield fluctuation, while the area of new cultivated land increased by land consolidation had an insignificant positive impact, which may be caused by the low quality of new cultivated land. According to the research results, the stable growth of grain production capacity can be achieved by strengthening comprehensive land consolidation, building high-standard farmland, increasing the area of cultivated land,improving the quality of newly added cultivated land, and introducing advanced agricultural production technology.
Learning engagement can not only predict the learning effect of college students, but also effectively evaluate the teaching quality of colleges and universities. In this study, 359 college students were selected as subjects,and the school belonging, the learning engagement and the life history strategy were measured through questionnaire survey. The results show that there was a significant positive correlation between college students’ sense of school belonging, the learning engagement and the life history strategy. The life history strategy plays a part of the mediating role between the school belonging and the learning engagement. Therefore, colleges and universities should improve students’ sense of school belonging by improving the quality of running schools, and adopt targeted teaching methods and encouragement measures according to students’ growing background and cognitive style in teaching so as to improve the learning engagement.
