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41.
This study provides a detailed report on the synthesis of spherical activated carbon with mesoporous structure using a soluble low molecular weight phenolic resol precursor through an ammonium alginate assisted sol–gel method. The effects of calcinating temperature and the addition of CaCO_3 as a pore-enlarging agent on texture structure and catalytic performance in isobutane dehydrogenation to isobutene were investigated. Characterization of N_2 sorption,mechanical strength tests,and optical photographs confirmed that the obtained carbon materials had high mechanical strength,a good degree of sphericity,and a large surface area. Introducing CaCO_3 as a pore-enlarging agent during the preparation process promoted the formation of a mesoporous structure of carbon spheres and evidently increased the surface area and oxygen content,which can improve isobutane conversion and isobutene selectivity of these carbon spheres. The conversion of isobutane reached up to 28% for this spherical activated carbon,and the selectivity of isobutene reached up to 96%. Isobutane conversion increased with an increase in calcination temperature due to an increase in the oxygen content,whereas the selectivity of isobutene decreased due to the slight decrease in the specific surface area. 相似文献
42.
康壮苏 《呼伦贝尔学院学报》2006,14(5):75-77
文章论述了构建区域科技创新体系应遵循的基本原则,并根据相关原则及各子系统的功能和相互关系构筑了区域科技创新体系组织结构的框架模型,即认为:区域科技创新体系包括两个层次、六个子系统。最后提出了推进区域科技创新体系建设的一些对策措施。 相似文献
43.
In Grutter vs. Bollinger, the U.S. Supreme Court ruled that the use of race as one factor, among many in admissions decisions is constitutional. It is not known, however, whether future legal opinions will continue to uphold the use of affirmative action policies. Some have argued that class-based preferences can achieve many of the same goals as in affirmative action while being more likely to withstand legal challenges. To date, no empirical studies have been conducted on the potential impact of a class-based admissions policy if implemented at an undergraduate institution. This paper reports on a study at a selective public college and compares a number of outcomes under three admissions models: the original admissions decisions, a purely academic model, and an socio-economic status (SES)-based model. The findings showed that use of the SES-based model would have led to a more academically qualified class than in the original admitted class while maintaining substantially greater student diversity that was found under the academic model. An admissions policy based on preferences for socio-economically disadvantaged applicants appears to hold promise for other colleges and universities with similar institutional and applicant characteristics. The ideas and research design reported in this paper are based on the doctoral dissertation study of the second author, Undergraduate Admissions Models Incorporating Socioeconomic Factors (Johnson, 2000). 相似文献
44.
曹康 《乌鲁木齐成人教育学院学报》2004,12(2):63-64
随着与国际社会交流机会的增多.英语水平成为衡量学生能力的一个重要方面,英语教学是高等职业技术学院教育中十分重要的一部分。当前,高职生英语基础较差.在专业英语授课过程中要强调同步复习这一环节。 相似文献
45.
思想政治理论课教学是大学生思想政治教育的主渠道和主阵地。为了提高新形势下思想政治理论课教学的实效性,必须通过以下环节和措施来实现:重点提高思想政治理论课教师的政治素养,进一步优化教学内容,改进教学方法,完善实践和考试环节,使思想政治理论课教学在思想道德建设方面起到独特的作用。 相似文献
46.
高等职业教育专业设置特色分析 总被引:1,自引:0,他引:1
专业设置是高等职业教育的基础。在教育比较的基础上,分析了高等职业教育专业设置的原则特色、结构特色、层次特色、名称的形式特色和机制特色,并就特色专业建设进行了探讨。力求为高等职业教育建设特色专业提供思路。 相似文献
47.
48.
ABSTRACTResearch Findings: Continuity of care is a recommended practice in child care intended to promote secure and supportive relationships between infants and toddlers and their caregivers. Toddlers (N = 115) between 12 and 24 months were observed in 30 continuity and 29 noncontinuity classrooms. The average duration of care for toddlers with caregivers was 14 months in the continuity rooms and 5 months in noncontinuity rooms. Toddlers observed in continuity rooms experienced higher levels of interactive involvement with their caregivers and were rated by their caregivers as having fewer problem behaviors compared with the toddlers in noncontinuity rooms. Toddlers in rooms with higher staff–child ratios also experienced more involved caregiving. We did not find evidence that the level of involved caregiving mediated the association between continuity of care and toddlers’ social competence or problem behaviors. Practice or Policy: Continuity of care may be a promising practice for programs that strive to provide high-quality care for infants and toddlers. 相似文献
49.
A large urban school district contracted with a private nonprofit educational foundation to train 126 special education resource
teachers in the last three years in an Orton-Gillingham-based program. These teachers are currently teaching learning-disabled
students in groups of 8–10 at the elementary level and 10–13 students at the secondary level. Learning-disabled students who
qualify for Special Education, either in reading or spelling, or both, are receiving the instruction.
The teachers took a Basic Introductory Class (90 hours of Advanced Academic Credit offered by the Texas Education Agency,
or six hours of graduate credit at a local university) in order to teach the program in the resource setting. A two year Advanced
Training included annual on-site observations, two half-day workshops each fall and spring, and a two-day advanced workshop
in the second summer.
First grade teachers, one selected from each of the 164 campuses, supervisors, and principals attended a 25-hour course on
“Recognizing Dyslexia: Using Multisensory Teaching and Discovery Techniques.” The first grade teachers and special education
resource teachers collaborated to provide inservice training for their colleagues.
Research, conducted by the district’s Research Department, reveals statistically significant gains in reading and spelling
ability for the learning-disabled resource students as measured by the Woodcock Reading Mastery Test-Revised, and the Test
of Written Spelling. 相似文献
50.
申跃中几十年起伏多变的创作命运,始终没有离开过中国当代这一特定历史时期时代因素的缠绕。这一因素既把他涌向潮头,也把他推向低谷,使他与时代、与社会结下了永远的不解之缘。在这一过程中,作家对创作道路的自觉选择和对艺术境界的自觉追求对创作命运具有重要意义,时代感召和主体抉择的共同作用,使作家走上了一条成功之路。 相似文献