Search results for: college selectivity
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 1383

Search results for: college selectivity

1323 Factors of English Language Learning and Acquisition at Bisha College of Technology

Authors: Khlaid Albishi

Abstract:

This paper participates in giving new vision and explains the learning and acquisition processes of English language by analyzing a certain context. Five important factors in English language acquisition and learning are discussed and suitable solutions are provided. The factors are compared with the learners' linguistic background at Bisha College of Technology BCT attempting to link the issues faced by students and the research done on similar situations. These factors are phonology, age of acquisition, motivation, psychology and courses of English. These factors are very important; because they interfere and affect specific learning processes at BCT context and general English learning situations.

Keywords: language acquisition, language learning, factors, Bisha college

Procedia PDF Downloads 475
1322 Effect of Digital Technology on Students Interest, Achievement and Retention in Algebra in Abia State College of Education (Technical) Arochukwu

Authors: Stephen O. Amaraihu

Abstract:

This research investigated the effect of Computer Based Instruction on Students’ interest, achievement, and retention in Algebra in Abia State College of Education (Technical), Arochukwu. Three research questions and two hypotheses guided the study. Two instruments, Maths Achievement Test (MAT) and Maths Interest Inventory were employed, to test a population of three hundred and sixteen (316) NCE 1 students in algebra. It is expected that this research will lead to the improvement of students’ performance and enhance their interest and retention of basic algebraic concept. It was found that the majority of students in the college are not proficient in the use of ICT as a result of a lack of trained personnel. It was concluded that the state government was not ready to implement the usage of mathematics in Abia State College of Education. The paper recommends, amongst others, the employment of mathematics Lectures with competent skills in ICT and the training of lecturers of mathematics.

Keywords: achievement, computer based instruction, interest, retention

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1321 International College Students Understand Entrepreneurial Readiness and Business-Related Skills: A Qualitative Study

Authors: Aleksandar Chonevski

Abstract:

The free-market economy provides many opportunities for entrepreneurship or starting one’s own business, attracting many students to study business at for-profit colleges in the United States. This is also true for international students, many of whom are filled with the hope of making a better life for themselves and their families through entrepreneurial endeavors. This qualitative research showed that not all graduates business students start their own business. In investigating this phenomenon, the effectiveness of entrepreneurship curricula at international colleges needs to be examined in order to adjust, improve and reform entrepreneurship curricula. This qualitative study will explore how business skills learned in college for-profit play a role in the entrepreneurial readiness of undergraduate business students in the south Florida. Business curricula helps international students achieve goals and transform their actions to understand challenges in a corporate society. Students will be interviewed to gain information about the students’ experience with entrepreneurship curricula in a for-profit college in south Florida.

Keywords: business skills, college curriculum, entrepreneurial readiness, international students

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1320 Mathematical Beliefs, Attitudes, and Performance of Freshman College Students

Authors: Johna Bernice Ablaza, Bryan Lim Corpuz, Joanna Marie Estrada, Mary Ann Cristine Olgado, Rhina Recato

Abstract:

This study aimed to describe the mathematical beliefs and attitudes in relation to the mathematics performance of freshman college students. The descriptive design using the correlational study was used to describe the relationship among mathematical beliefs, attitudes, and performance of freshman college students. This study involved one hundred fifty (150) freshman college students of Philippine Normal University during the third trimester of school year 2015-2016. The research instruments used to gather the information needed in the study are the beliefs about Mathematics Questionnaire, the KIM-Project Questionnaire, and the ACT Compass Mathematics Test. The data gathered were analyzed using the percentages, mean, standard deviation, and Pearson r-moment correlation. The results of this study have shown that although students believe that Mathematics is significant in their lives, the overall result on their beliefs and attitudes are positively low. There is a significant relationship between the students’ mathematical beliefs and mathematics performance. Likewise, their attitudes in mathematics have significant relationship to mathematics performance.

Keywords: attitudes, diligence, interest, mathematical beliefs, mathematical performance, self-confidence

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1319 Students' Perspectives on Quality of Course Evaluation Practices and Feedbacks in Eritrea

Authors: Ermias Melake Tesfay

Abstract:

The importance of evaluation practice and feedback to student advancement and retention has gained importance in the literature over the past ten years. So many issues and cases have been raised about the quality and types of evaluation carried out in higher education and the quality and quantity of student feedback. The aim of this study was to explore the students’ perspectives on the quality of course evaluation practice and feedback in College of Education and College of Science. The study used both quantitative and qualitative methods to collect data. Data were collected from third-year and fourth-year students of 13 departments in the College of Education and College of Science in Eritrea. A modified Service Performance (SERVPERF) questionnaire and focus group discussions were used to collect the data. The sample population comprised of 135 third-year and fourth-year students’ from both Colleges. A questionnaire using a 5 point Likert-scale was administered to all respondents whilst two focus group discussions were conducted. Findings from survey data and focus group discussions showed that the majority of students hold a positive perception of the quality of course evaluation practice but had a negative perception of methods of awarding grades and administrators’ role in listening to the students complain about the course. Furthermore, the analysis from the questionnaire showed that there is no statistically significant difference between third-year and fourth-year students, College of Education and College of Science and male and female students on the quality of course evaluation practice and feedback. The study recommends that colleges improve the quality of fairness and feedback during course assessment.

Keywords: evaluation, feedback, quality, students' perception

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1318 Methanation Catalyst for Low CO Concentration

Authors: Hong-Fang Ma, Cong-yi He, Hai-Tao Zhang, Wei-Yong Ying, Ding-Ye Fang

Abstract:

A Ni-based catalyst supported by γ-Al2O3 was prepared by impregnation method, and the catalyst was used in a low CO and CO2 concentration methanation system. The effect of temperature, pressure and space velocity on the methanation reaction was investigated in an experimental fixed-bed reactor. The methanation reaction was operated at the conditions of 190-240°C, 3000-24000ml•g-1•h-1 and 1.5-3.5MPa. The results show that temperature and space velocity play important role on the reaction. With the increase of reaction temperature the CO and CO2 conversion increase and the selectivity of CH4 increase. And with the increase of the space velocity the conversion of CO and CO2 and the selectivity of CH4 decrease sharply.

Keywords: coke oven gas, methanntion, catalyst, fixed bed, performance

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1317 Characteristics and Guiding Strategies of College Students' Online Discourse: Based on the Analysis of One Student Forum

Authors: Hanwei Cheng, Chengbei Xu, Yijie Wang

Abstract:

More and more college students are accustomed to surfing the Internet everyday. As community members, college students have ability to express opinions and participate in social affairs, they not only accept information passively, but also voice their concerns on the Internet. We interpret the online discourses featured with anonymization, so it helps us more effectively and conveniently understand the behaviors and thoughts of college students, and educators can thus grasp the scales and directions in guiding online language. We analyzed online comments in both content and form aspects in one student forum (named Dandan, the BNU’s campus forum), and through methods of literature review and interview, we found that in term of content, college students pay attention to practical information online, emphasize on personal development and pursue hot issues; in term of form, college students' online language displays cross-border quality sometimes under the general feature of normative, and they often explore a certain topic in the form of question or discussion, and they like to show feelings in ironic and stream-of-consciousness ways. It is argued that college students intend to establish a community to facilitate personal development and meet emotional needs through the student forum, and by making comments at the forum they are also able to get involved in public affairs. We should pay attention to problems of college students' online discourse, such as boundary issues (like informal advertisement and information authenticity), emotional issues and the spread of gossip. Some possible solutions to solving online discourse problems can be applied, like we can improve access systems of student forum, clarify principles of Internet langue use, change oversimplified management approaches and use some other tactics, in order to form a mechanism of student self-regulation, also deepen the trust and cooperation between school administrators and students.

Keywords: online language, youth discourse, content and form, implication and strategy

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1316 Semantic Analysis of the Change in Awareness of Korean College Admission Policy

Authors: Sujin Hwang, Hyerang Park, Hyunchul Kim

Abstract:

The purpose of this study is to find the effectiveness of the admission simplification policy. The number of online news articles about ‘high school record’ was collected and semantically analyzed to identify and analyze the social awareness during 2014 to 2015. The main results of the study are as follows: First, there was a difference in expectations that the burden of the examinees would decrease as announced by KCUE. Thus, there was still a strain on the university entrance exam after the enforcement of the policy. Second, private tutoring is expanding in different forms, rather than reducing the policy. It is different from the prediction that examinees can prepare for university admissions without the private tutoring. Thus, the college admission rules currently enforced needs to be improved. The reasonable college admission system changes are discussed.

Keywords: education policy, private tutoring, shadow education, education admission policy

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1315 Student-Athletes Self-Concept, GPA and Training in the Climate of Social Networking

Authors: Indhumathi Gopal, Ashley Johnson

Abstract:

Social media use for communication among college student-athletes is growing. There is little research on student-athletes use of Blogs, one of the online communication tool outlets. Twenty-seven student-athletes, aged 18-24 years completed a student perception questionnaire which assessed demographics, the effect of blogging on college student-athletes self-concept, the correlation of age, GPA and blogging as well as the training students received in the use of social media. Descriptive statistics and Pearson correlations were analyzed examined. Results indicated a significant correlation between use of Blogs and student age (p < .01) and student GPA earned (p < .01). With respect to self-concept, results suggest that blogging could be a useful tool for communication but can present challenges, could affect student self-esteem either, positively or negatively. The training student-athletes received in the use of social media was not adequate. College athletes’ can more easily divulge information about their personal lives and opinions on social media and challenge the athletic programs and their own future. The findings of the study suggest implications for student-athletes to be better prepared for the current media climate.

Keywords: college student-athletes, self-concept, use of social media training, social networking

Procedia PDF Downloads 571
1314 Validation of the Career Motivation Scale among Chinese University and Vocational College Teachers

Authors: Wei Zhang, Lifen Zhao

Abstract:

The present study aims to translate and validate the Career Motivation Scale among Chinese university and vocational college teachers. Exploratory factor analysis supported a three-factor structure that was consistent with the original structure of career motivation: career insight, career identity, and career resilience. Confirmatory factor analysis showed that a second-order three-factor model with correlated measurement errors best fit the data. Configural, metric, and scalar invariance models were tested, demonstrating that the Chinese version of the Career Motivation Scale did not differ across groups of school type, educational level, and working years in current institutions. The concurrent validity of the Chinese Career Motivation Scale was confirmed by its significant correlations with work engagement, career adaptability, career satisfaction, job crafting, and intention to quit. The results of the study indicated that the Chinese Career Motivation Scale was a valid and reliable measure of career motivation among university and vocational college teachers in China.

Keywords: career motivation scale, Chinese University, vocational college teachers, measurement invariance, validation

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1313 College Readiness Outcomes of No Child Left Behind: A Critical Analysis

Authors: Tianyu Chen

Abstract:

The No Child Left Behind Act (NCLB) of 2001 was a major federal education policy that aimed to improve academic outcomes for all students in the United States. This study examines whether NCLB improved college readiness, measured by access to higher education, for different demographic groups. Using data from the Integrated Public Use Microdata Series (IPUMS) from 2003-2008, regression analyses explore the relationship between gender, race, family income, and region with occupational education score. The results indicate that NCLB implementation had a positive effect on college access for women and Asian students compared to other groups. Higher family income was also associated with an increased likelihood of pursuing higher education, especially for families in the South. While NCLB intended to close achievement gaps, disparities in college readiness remained five years after implementation. Further research could examine longer-term trends and additional factors influencing the policy's effectiveness across student subgroups. This study provides evidence that simply holding schools accountable for test scores may not sufficiently improve equitable educational outcomes. More targeted support of disadvantaged groups may be needed to fulfill the goal of "no child left behind."

Keywords: no child left behind act, college readiness, achievement gaps, educational equity

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1312 Guidelines for School Management to Enhance School Engagement of Bangkok Christian College Students

Authors: Wichai Srisud, Shunnawat Pungbangkradee, Sukanya Chaemchoy

Abstract:

This research study aims to analyze and assess school management guidelines designed to enhance the level of Student School Engagement of students at Bangkok Christian College, according to three following primary objectives: 1) to evaluate the level of Student School Engagement among Bangkok Christian College students, 2) to examine the Priority Needs Index of school management for promoting an optimum level of Student School Engagement among Bangkok Christian College students, and 3) to develop additional guidelines for school management to further enhance the level of Student School Engagement of Bangkok Christian College students. The research was conducted using Explanatory Design research methodology, with data obtained from a sample comprised of 291 students and 6 administrative personnel. The research findings indicated that: 1) The overall level of Student School Engagement was high. Emotional engagement averaged at the highest level, followed by Behavioral Engagement and Cognitive Engagement, respectively. 2) The Priority Needs Index of school management for promoting Student School Engagement of Bangkok Christian College students was examined, revealing that Evaluation averaged at the highest PNI level, followed by Planning and Implementation, respectively. 3) Guidelines for school management to enhance Student School Engagement of Bangkok Christian College students should consist of four approaches: 3.1) A Cognitive Engagement Enhancing Approach, which must include (1) fostering students’ problem-solving flexibility, and their ability to devise solutions for overcoming potential challenges, and (2) encouraging students to deal effectively with academic setbacks, rather than becoming overwhelmed by what they may perceive as failures, 3.2) An Emotional Engagement Enhancing Approach, cultivating students’ interests, aspirations and goals in learning to maximize emotional investment in their academic pursuits, and 3.3) A Behavioral Engagement Enhancing Approach, for elevating students’ focus and attentiveness during learning, and improving their ability to avoid distractions during study time.

Keywords: school engagement, guidelines for school management

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1311 Administration Model for the College of Film, Television, Multimedia and Performing Arts, Suan Sunandha Rajabhat University

Authors: Somdech Rungsrisawat

Abstract:

The objective of this research was to investigate how to develop an appropriate management and administration model for the College of Film, Television, Multimedia and Performing Arts at Suan Sunandha Rajabhat University. A combination of qualitative and quantitative data collection and analysis methods was employed. The data collection was from the 8 experts who were the academic staff and entrepreneurs in films, television, multimedia and performing arts, and from 471 students studying in the communication arts field. The findings of this research paper presented the appropriate management and administration model for the College of Film, Television, Multimedia and Performing Arts, which depended on 3 factors: [i] the marketing management and the supporting facilities such as buildings, equipments and accessibility for students to the college; [ii] the competency of academic staff or lecturers and supporting staff; and [iii] career opportunities after graduation.

Keywords: educational institution management, educational management, learning resources, non-formal education, Thai qualifications framework for higher education

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1310 On the Allopatry of National College Entrance Exam in China: The Root, Policy and Strategy

Authors: Shi Zhang

Abstract:

This paper aims to introduce the allopatry of national college entrance examination which allow migrant students enter senior high schools and take college entrance exam where they live, identifies the reasons affect the implementation of this policy in the Chinese context. Most of China’s provinces and municipalities recently have announced new policies regarding national college entrance exams for non-local students. The paper conducts SWOT analysis reveals the opportunities, strength, weakness and challenges of the scheme, so as to discuss the implementation strategies from the perspectives of idea and institution. The research findings imply that the government should take a more positive attitude toward relaxing the allopatry of NCEE policy restrictions, and promote the reform household registration policy and NCEE policy with synchronous operations. Higher education institutions should explore the diversification of enrollment model; the government should issue the authority of universities and colleges to select elite migrant students beyond the restrictions of NCEE. To suit reform policies to local conditions, the big cities such as Beijing, Shanghai and Guangzhou should publish related compensate measures for children of migrant workers access to higher vocational colleges with tuition fee waivered. 

Keywords: college entrance examination, higher education, education policy, education equality

Procedia PDF Downloads 360
1309 Selectivity Mechanism of Cobalt Precipitation by an Imidazole Linker From an Old Battery Solution

Authors: Anna-Caroline Lavergne-Bril, Jean-François Colin, David Peralta, Pascale Maldivi

Abstract:

Cobalt is a critical material, widely used in Li-ion batteries. Due to the planned electrification of European vehicles, cobalt needs are expending – and resources are limited. To meet the needs in cobalt to come, it is necessary to develop new efficient ways to recycle cobalt. One of the biggest sources comes from old electrical vehicles batteries (batteries sold in 2019: 500 000 tons of waste to be). A closed loop process of cobalt recycling has been developed and this presentation aims to present the selectivity mechanism of cobalt over manganese and nickel in solution. Cobalt precipitation as a ZIF material (Zeolitic Imidazolate framework) from a starting solution composed of equimolar nickel, manganese and cobalt is studied. A 2-MeIm (2-methylimidazole) linker is introduced in a multimetallic Ni, Mn, Co solution and the resulting ZIF-67 is 100% pure Co among its metallic centers. Selectivity of Co over Ni is experimentally studied and DFT modelisation calculation are conducted to understand the geometry of ligand-metal-solvent complexes in solution. Selectivity of Co over Mn is experimentally studied, and DFT modelisation calcucation are conducted to understand the link between pKa of the ligand and precipitration of Mn impurities within the final material. Those calculation open the way to other ligand being used in the same process, with more efficiency. Experimental material are synthetized from bimetallic (Ni²⁺/Co²⁺, Mn²⁺/Co²⁺, Mn²⁺/Ni²⁺) solutions. Their crystallographic structure is analysed by XRD diffraction (Brüker AXS D8 diffractometer, Cu anticathode). Morphology is studied by scanning electron microscopy, using a LEO 1530 FE-SEM microscope. The chemical analysis is performed by using ICP-OES (Agilent Technologies 700 series ICP-OES). Modelisation calculation are DFT calculation (density functional theory), using B3LYP, conducted with Orca 4.2.

Keywords: MOFs, ZIFs, recycling, closed-loop, cobalt, li-ion batteries

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1308 Disciplinary Problems among Adeyemi College of Education Students in the Ondo State of Nigeria

Authors: Akinyemi Olufunminiyi Akinbobola

Abstract:

This paper analytically discusses the disciplinary problems among Adeyemi College of Education Students in the Ondo State of Nigeria. The paper posits that the causes and types of disciplinary problems experienced by the students are determinacy of disciplinary measures to be taken. The study used a questionnaire titled: Disciplinary Problem Questionnaire (DPQ) to collect data. Five hundred (500) students were randomly sampled in the five schools in the college. The results showed that drug addiction, school curriculum, cultism, peer group influence, overcrowded classroom, political, social, and economic among others are disciplinary problems experienced in the study area. The study made recommendations on how to improve the situation.

Keywords: challenges in higher institutions, disciplinary problems, social vices, students’ indiscipline

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1307 Impact of Zn/Cr Ratio on ZnCrOx-SAPO-34 Bifunctional Catalyst for Direct Conversion of Syngas to Light Olefins

Authors: Yuxuan Huang, Weixin Qian, Hongfang Ma, Haitao Zhang, Weiyong Ying

Abstract:

Light olefins are important building blocks for chemical industry. Direct conversion of syngas to light olefins has been investigated for decades. Meanwhile, the limit for light olefins selectivity described by Anderson-Schulz-Flory (ASF) distribution model is still a great challenge to conventional Fischer-Tropsch synthesis. The emerging strategy called oxide-zeolite concept (OX-ZEO) is a promising way to get rid of this limit. ZnCrOx was prepared by co-precipitation method and (NH4)2CO3 was used as precipitant. SAPO-34 was prepared by hydrothermal synthesis, and Tetraethylammonium hydroxide (TEAOH) was used as template, while silica sol, pseudo-boehmite, and phosphoric acid were Al, Si and P source, respectively. The bifunctional catalyst was prepared by mechanical mixing of ZnCrOx and SAPO-34. Catalytic reactions were carried out under H2/CO=2, 380 ℃, 1 MPa and 6000 mL·gcat-1·h-1 in a fixed-bed reactor with a quartz lining. Catalysts were characterized by XRD, N2 adsorption-desorption, NH3-TPD, H2-TPR, and CO-TPD. The addition of Al as structure promoter enhances CO conversion and selectivity to light olefins. Zn/Cr ratio, which decides the active component content and chemisorption property of the catalyst, influences CO conversion and selectivity to light olefins at the same time. C2-4= distribution of 86% among hydrocarbons at CO conversion of 14% was reached when Zn/Cr=1.5.

Keywords: light olefins, OX-ZEO, Syngas, ZnCrOₓ

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1306 Separation Performance of CO₂ by Mixed Matrix Membrane Comprising Carbide-Derived Carbon

Authors: Musa Najimu, Isam Aljundi

Abstract:

In this study, the development of mixed matrix membrane (MMM) containing carbide-derived carbon (CDC) for the separation of CO₂ was investigated. MMM with four different loadings (0.1 to 2 wt%) were prepared by the dry/wet phase inversion technique. Prior to this, the formula of the control polysulfone (PSF) membrane was optimized in terms of the PSF concentration in a mixture of NMP/THF solvents and ethanol. Prepared samples were characterized and tested for CO₂ and CH₄ gas permeation. The optimization of the control PSF membrane revealed that 30 wt% PSF is the critical polymer concentration in the formulation. Characterization results unveiled reinforcement of thermal stability and improved polarity imparted by CDC in the MMM, in addition to uniform dispersion of filler up to 1 wt% loading. Furthermore, the incorporation of CDC in PSF membrane formulation enhanced both the CO₂ permeance and ideal selectivity over the control membrane. A CDC loading of 0.5 wt% resulted in the highest CO₂ permeance of 5.5 GPU corresponding to 120% increase in permeance while a CDC loading of 1 wt% resulted in the highest selectivity (CO₂ /CH₄) of 27 corresponding to 29% increase in selectivity. Studies of operating temperature effect showed that an optimum operating temperature for M1.0 membrane is 20 ⁰C. In addition, the feed pressure studies showed that high pressure feeds will favor high performance of the membrane and a good CO₂ /CH₄ separation.

Keywords: carbide derived carbon, mixed matrix membrane, CO₂ separation, polysulfone

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1305 The Efficiency of the Use of Medical Bilingual Dictionary in English Language Teaching in Vocational College

Authors: Zorana Jurinjak, Christos Alexopoulos

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The aim of this paper is to examine the effectiveness of using a medical bilingual dictionary in teaching English in a vocational college. More precisely, to what extent the use of bilingual medical dictionary in relation to the use of Standard English bilingual dictionaries influences the results on tests, and thus the acquisition of better competence of students mastering the subject terminology. Secondary interest in this paper would be to raise awareness among students and teachers about the advantages of dictionary use. The experiment was conducted at College of Applied Health Sciences in Ćuprija on a sample of 90 students. The respondents translated three medical texts with 42 target terms. Statistical analyses of the data obtained show that the differences in average time and correct answers favor the students who used medical dictionary.

Keywords: bilingual medical dictionary, standard english bilingual dictionary, medical terminology, EOS, ESP

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1304 The Relationship between the Personality Traits and Self-Compassion with Psychological Well-Being in Iranian College Students

Authors: Abdolamir Gatezadeh, Rezvan K. A. Mohamamdi, Arash Jelodari

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It has been well established that personality traits and self-compassion are associated with psychological well-being. Thus, the current research aimed to investigate the underlying mechanisms in a collectivist culture. Method: One hundred and fifty college students were chosen and filled out Ryff's Psychological Well-Being Scale, the NEO Personality Inventory, and Neff's Self-Compassion Scale. Results: The results of correlation analysis showed that there were significant relationships between the personality traits (neuroticism, extraversion, agreeableness, and conscientiousness) and self-compassion (self-kindness, isolation, mindfulness, and the total score of self-compassion) with psychological well-being. The regression analysis showed that neuroticism, extraversion, and conscientiousness significantly predicted psychological well-being. Discussion and conclusion: The cultural implications and future orientations have been discussed.

Keywords: college students, personality traits, psychological well-being, self-compassion

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1303 Solid-Liquid-Polymer Mixed Matrix Membrane Using Liquid Additive Adsorbed on Activated Carbon Dispersed in Polymeric Membrane for CO2/CH4 Separation

Authors: P. Chultheera, T. Rirksomboon, S. Kulprathipanja, C. Liu, W. Chinsirikul, N. Kerddonfag

Abstract:

Gas separation by selective transport through polymeric membranes is one of the rapid growing branches of membrane technology. However, the tradeoff between the permeability and selectivity is one of the critical challenges encountered by pure polymer membranes, which in turn limits their large-scale application. To enhance gas separation performances, mixed matrix membranes (MMMs) have been developed. In this study, MMMs were prepared by a solution-coating method and tested for CO2/CH4 separation through permeability and selectivity using a membrane testing unit at room temperature and a pressure of 100 psig. The fabricated MMMs were composed of silicone rubber dispersed with the activated carbon individually absorbed with polyethylene glycol (PEG) as a liquid additive. PEG emulsified silicone rubber MMMs showed superior gas separation on cellulose acetate membrane with both high permeability and selectivity compared with silicone rubber membrane and alone support membrane. However, the MMMs performed limited stability resulting from the undesirable PEG leakage. To stabilize the MMMs, PEG was then incorporated into activated carbon by adsorption. It was found that the incorporation of solid and liquid was effective to improve the separation performance of MMMs.

Keywords: mixed matrix membrane, membrane, CO₂/CH₄ separation, activated carbon

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1302 Modification of Carbon-Based Gas Sensors for Boosting Selectivity

Authors: D. Zhao, Y. Wang, G. Chen

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Gas sensors that utilize carbonaceous materials as sensing media offer numerous advantages, making them the preferred choice for constructing chemical sensors over those using other sensing materials. Carbonaceous materials, particularly nano-sized ones like carbon nanotubes (CNTs), provide these sensors with high sensitivity. Additionally, carbon-based sensors possess other advantageous properties that enhance their performance, including high stability, low power consumption for operation, and cost-effectiveness in their construction. These properties make carbon-based sensors ideal for a wide range of applications, especially in miniaturized devices created through MEMS or NEMS technologies. To capitalize on these properties, a group of chemoresistance-type carbon-based gas sensors was developed and tested against various volatile organic compounds (VOCs) and volatile inorganic compounds (VICs). The results demonstrated exceptional sensitivity to both VOCs and VICs, along with the sensor’s long-term stability. However, this broad sensitivity also led to poor selectivity towards specific gases. This project aims at addressing the selectivity issue by modifying the carbon-based sensing materials and enhancing the sensor's specificity to individual gas. Multiple groups of sensors were manufactured and modified using proprietary techniques. To assess their performance, we conducted experiments on representative sensors from each group to detect a range of VOCs and VICs. The VOCs tested included acetone, dimethyl ether, ethanol, formaldehyde, methane, and propane. The VICs comprised carbon monoxide (CO), carbon dioxide (CO2), hydrogen (H2), nitric oxide (NO), and nitrogen dioxide (NO2). The concentrations of the sample gases were all set at 50 parts per million (ppm). Nitrogen (N2) was used as the carrier gas throughout the experiments. The results of the gas sensing experiments are as follows. In Group 1, the sensors exhibited selectivity toward CO2, acetone, NO, and NO2, with NO2 showing the highest response. Group 2 primarily responded to NO2. Group 3 displayed responses to nitrogen oxides, i.e., both NO and NO2, with NO2 slightly surpassing NO in sensitivity. Group 4 demonstrated the highest sensitivity among all the groups toward NO and NO2, with NO2 being more sensitive than NO. In conclusion, by incorporating several modifications using carbon nanotubes (CNTs), sensors can be designed to respond well to NOx gases with great selectivity and without interference from other gases. Because the response levels to NO and NO2 from each group are different, the individual concentration of NO and NO2 can be deduced.

Keywords: gas sensors, carbon, CNT, MEMS/NEMS, VOC, VIC, high selectivity, modification of sensing materials

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1301 Catalytic Study of Methanol-to-Propylene Conversion over Nano-Sized HZSM-5

Authors: Jianwen Li, Hongfang Ma, Weixin Qian, Haitao Zhang, Weiyong Ying

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Methanol-to-propylene conversion was carried out in a continuous-flow fixed-bed reactor over nano-sized HZSM-5 zeolites. The HZSM-5 catalysts were synthesized with different Si/Al ratio and silicon sources, and treated with NaOH. The structural property, morphology, and acidity of catalysts were measured by XRD, N2 adsorption, FE-SEM, TEM, and NH3-TPD. The results indicate that the increment of Si/Al ratio decreased the acidity of catalysts and then improved propylene selectivity, while silicon sources had slight impact on the acidity but affected the product distribution. The desilication after alkali treatment could increase intracrystalline mesopores and enhance propylene selectivity.

Keywords: alkali treatment, HZSM-5, methanol-to-propylene, synthesis condition

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1300 Butene Catalytic Cracking to Propylene over Iron and Phosphorus Modified HZSM-5

Authors: Jianwen Li, Hongfang Ma, Haitao Zhang, Qiwen Sun, Weiyong Ying

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HZSM-5 zeolites modified by iron and phosphorus were applied in catalytic cracking of butene. N2 adsorption and NH3-TPD were employed to measure the structure and acidity of catalysts. The results indicate that increasing phosphorus loading decreased surface area, pore volume and strong acidity of catalysts. The introduction of phosphorus significantly decreased butene conversion and promoted propylene selectivity. The catalytic performance of catalyst was strongly dependent on the reaction conditions. Appropriate reaction conditions could suppress side reactions and enhance propylene selectivity.

Keywords: butene catalytic cracking, HZSM-5, modification, reaction conditions

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1299 Health and Mental Health among College Students: Toward a Better Understanding of the Impact of Sexual Assault, Alcohol Use, and COVID-19

Authors: Noel Busch-Armendariz, Caitlin Sulley

Abstract:

Introduction: This study investigated the development of college experiences, COVID-19 pandemic experiences, alcohol use, and sexual violence. The longitudinal study includes 656 college students living in the same dormitory. Students' alcohol use and social network structure were investigated to better understand the relationship with sexual violence risk. Basic Methodologies: Over two years, students repeated five web-based surveys, including a pre-college survey and surveys during four consecutive semesters. Questions were added in the fourth wave to assess students’ experiences of the COVID-19 pandemic, administered from November-January 2021, including mental and behavioral health. Analyses include the impact of COVID on living arrangements, drinking behaviors, and daily life; experiences of COVID symptoms, testing, and diagnosis, responses to COVID such as social distancing, quarantining, not working, increased health care needs; experience of fear, worry, stigma, emotional well-being, loneliness, and mental health; experiences of financial loss, lack of basic supplies, receiving emotional and financial support, and comparison with academic disengagement. Concluding Statement: Findings and discussion will include strategies to strengthen mental and behavioral health programs and policies.

Keywords: COVID, mental health, substance abuse, college students, sexual misconducts

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1298 An Evaluation of English Collocation Usage Barriers Faced by College Students of Rawalpindi

Authors: Sobia Rana

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The study intends to explain the problems of English collocational use faced by college students in Rawalpindi, Pakistan and recommends some authentic ways that will help in removing the learning barriers in light of the concerning methodological issues. It will not only help the students to improve their knowledge of the phenomena but will also enlighten the target teachers about the significance of authentic collocational use and how it naturalizes both written and spoken expressions. Data from both the students and teachers have been collected with the help of open/close-ended questionnaires to unearth the genuine cause/s and supplement them with the required solutions rooted in the actual problems. The students fail to use authentic collocations owing to multiple reasons: lack of awareness about English collocational use, improper teaching methodologies, and inexpert teachers.

Keywords: English collocational use, teaching methodologies, English learning barriers, vocabulary acquisition, college students of Rawalpindi

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1297 Effect of Positive Psychology (PP) Interventions on College Students’ Well-Being, Career Stress and Coronavirus Anxiety

Authors: Erva Kaygun

Abstract:

The purpose of this research is to investigate the effects of positive psychology interventions on college students' positive-negative emotions, coronavirus anxiety, and career stress. 4 groups of college students are compared in terms of the level of exposure to PP constructs ( Non-Psychology, Psychology, Positive Psychology Course, and Positive Psychology Boot Camp). In this research, Pearson Correlation, independent t-tests, ANOVA, and Post-Hoc tests are conducted. Without being significant, the groups exposed to PP constructs showed higher positive emotions and total PERMA scores, whereas negative emotions, career stress, and coronavirus stress remained similar. It is crucial to indicate that career stress is higher among all psychology students when compared to non-psychology students. The results showed that the highest exposure group (PP Boot Camp) showed no difference in negative emotions, whereas higher PERMA scores and positive emotion scores were on the Positive and Negative Affect Schedule (PANAS) scale.

Keywords: positive psychology, college students, well being, anxiety

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1296 CO₂ Conversion by Low-Temperature Fischer-Tropsch

Authors: Pauline Bredy, Yves Schuurman, David Farrusseng

Abstract:

To fulfill climate objectives, the production of synthetic e-fuels using CO₂ as a raw material appears as part of the solution. In particular, Power-to-Liquid (PtL) concept combines CO₂ with hydrogen supplied from water electrolysis, powered by renewable sources, which is currently gaining interest as it allows the production of sustainable fossil-free liquid fuels. The proposed process discussed here is an upgrading of the well-known Fischer-Tropsch synthesis. The concept deals with two cascade reactions in one pot, with first the conversion of CO₂ into CO via the reverse water gas shift (RWGS) reaction, which is then followed by the Fischer-Tropsch Synthesis (FTS). Instead of using a Fe-based catalyst, which can carry out both reactions, we have chosen the strategy to decouple the two functions (RWGS and FT) on two different catalysts within the same reactor. The FTS shall shift the equilibrium of the RWGS reaction (which alone would be limited to 15-20% of conversion at 250°C) by converting the CO into hydrocarbons. This strategy shall enable optimization of the catalyst pair and thus lower the temperature of the reaction thanks to the equilibrium shift to gain selectivity in the liquid fraction. The challenge lies in maximizing the activity of the RWGS catalyst but also in the ability of the FT catalyst to be highly selective. Methane production is the main concern as the energetic barrier of CH₄ formation is generally lower than that of the RWGS reaction, so the goal will be to minimize methane selectivity. Here we report the study of different combinations of copper-based RWGS catalysts with different cobalt-based FTS catalysts. We investigated their behaviors under mild process conditions by the use of high-throughput experimentation. Our results show that at 250°C and 20 bars, Cobalt catalysts mainly act as methanation catalysts. Indeed, CH₄ selectivity never drops under 80% despite the addition of various protomers (Nb, K, Pt, Cu) on the catalyst and its coupling with active RWGS catalysts. However, we show that the activity of the RWGS catalyst has an impact and can lead to longer hydrocarbons chains selectivities (C₂⁺) of about 10%. We studied the influence of the reduction temperature on the activity and selectivity of the tandem catalyst system. Similar selectivity and conversion were obtained at reduction temperatures between 250-400°C. This leads to the question of the active phase of the cobalt catalysts, which is currently investigated by magnetic measurements and DRIFTS. Thus, in coupling it with a more selective FT catalyst, better results are expected. This was achieved using a cobalt/iron FTS catalyst. The CH₄ selectivity dropped to 62% at 265°C, 20 bars, and a GHSV of 2500ml/h/gcat. We propose that the conditions used for the cobalt catalysts could have generated this methanation because these catalysts are known to have their best performance around 210°C in classical FTS, whereas the iron catalysts are more flexible but are also known to have an RWGS activity.

Keywords: cobalt-copper catalytic systems, CO₂-hydrogenation, Fischer-Tropsch synthesis, hydrocarbons, low-temperature process

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1295 Post-Combustion CO₂ Capture: From Membrane Synthesis to Module Intensification

Authors: Imran Khan Swati, Mohammad Younas

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This work aims to explore the potential applications of polymeric hydrophobic membranes and green ionic liquids (ILs). Protic and aprotic ILs were synthesized in the lab., characterized, and tested for CO₂/N₂ and CO₂/CH₄ separation using hydrophobic polymeric membranes via supported ionic liquid membrane (SILM). ILs were verified by FTIR spectroscopy. The SILMs were stable at room temperature up to 0.5 MPa. For CO₂, [BSmim][tos] had the greatest coefficient of solubility and permeability, along with all ILs. At 0.5 MPa, IL [BSmim][tos] was found with a selectivity of 56.2 and 47.5 for pure CO₂/N₂ and CO₂/CH₄, respectively. The ILs synthesized for this study are rated as [BSmim][tos]>[BSmpy][tos]>[Bmim][Cl]>[Bpy][Cl] based on their SILM separation performance. Furthermore, high values of selectivity of [BSmim][tos] and [BSmpy][tos] support the use of ILs for CO₂ separation using SILMs. The study was extended to synthesize and test the ammonium-based ILs, [2-HEA][f] and [2-HEA][Hs]. These ILs achieved 50 % less selectivity for CO₂/N₂ as compared to [BSmim][tos] and [BSmpy][tos]. Nevertheless, the permeability of CO₂ achieved with [2-HEA][f] and [2-HEA][Hs] is more than 20 times higher than the [BSmim][tos] and [BSmpy][tos]. Later, the CO₂/N₂ permeability and selectivity study was extended using a flat sheet membrane contactor with recirculated IL. The contact angle effects, liquid entry pressure (LEP), initial CO₂ concentration, and type of solvents and membrane material on the CO₂ capture efficiency and membrane wetting in the post-combustion capture (PCC) process have been experimentally investigated and evaluated. Polytetrafluoroethylene (PTFE) has shown the most hydrophobic property with 6-170 loss in the contact angle. Furthermore, [Omim][BF4] and [Bmim][BF6] have exhibited only 5-8 % loss in LEP using PTFE membrane support. The CO₂ capture efficiency has been achieved as 80.8-99.8 % in different combinations of ILs and membrane support, keeping all other variables constant. While increasing CO₂ concentration from 15 to 45 % vol., an increase of nearly three folds in the CO₂ mass transfer flux was observed. The combination of [Omim][BF4] and PTFE membrane witnessed good long-term stability with only a 20 % loss in CO₂ capture efficiency in 480 min of continuous operation. A 3- D simulation model for non-dispersive solvent absorption in membrane contactors provides insight into the optimum design of a separation system for a specific application minimizing the overall cost and making the process environment-friendly.

Keywords: Post-combustion CO2 capture, membrane synthesis, process development, permeability and selectivity, ionic liquids

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1294 Closing the Assessment Loop: Case Study in Improving Outcomes for Online College Students during Pandemic

Authors: Arlene Caney, Linda Fellag

Abstract:

To counter the adverse effect of Covid-19 on college student success, two faculty members at a US community college have used web-based assessment data to improve curricula and, thus, student outcomes. This case study exemplifies how “closing the loop” by analyzing outcome assessments in real time can improve student learning for academically underprepared students struggling during the pandemic. The purpose of the study was to develop ways to mitigate the negative impact of Covid-19 on student success of underprepared college students. Using the Assessment, Evaluation, Feedback and Intervention System (AEFIS) and other assessment tools provided by the college’s Office of Institutional Research, an English professor and a Music professor collected data in skill areas related to their curricula over four semesters, gaining insight into specific course sections and learners’ performance across different Covid-driven course formats—face-to-face, hybrid, synchronous, and asynchronous. Real-time data collection allowed faculty to shorten and close the assessment loop, and prompted faculty to enhance their curricula with engaging material, student-centered activities, and a variety of tech tools. Frequent communication, individualized study, constructive criticism, and encouragement were among other measures taken to enhance teaching and learning. As a result, even while student success rates were declining college-wide, student outcomes in these faculty members’ asynchronous and synchronous online classes improved or remained comparable to student outcomes in hybrid and face-to-face sections. These practices have demonstrated that even high-risk students who enter college with remedial level language and mathematics skills, interrupted education, work and family responsibilities, and language and cultural diversity can maintain positive outcomes in college across semesters, even during the pandemic.

Keywords: AEFIS, assessment, distance education, institutional research center

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