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31.
中华文化博大精深,作为中华文化的重要成员之一,茶文化对其传承与发扬起到了不容忽视的作用。在当代,茶文化与现代科技充分融合,发展成了新时期的现代茶文化,同时,又更好地弘扬了中华文化。本文紧绕中国茶文化门户网站,从网站的茶文化主题、茶文化结构、茶文化模式三方面进行了文化分析,以展示出现代茶文化的文化价值。  相似文献   
32.
Theaflavins (TFs) are the dimers of a couple of epimerized catechins, which are specially formed during black tea fermentation. To explore the differences among four main TF derivatives (theaflavin (TF1), theaflavin-3-gallate (TF2A), theaflavin-3′-gallate (TF2B), and theaflavin-3,3′-digallate (TF3)) in scavenging reactive oxygen species (ROS) in vitro, their properties of inhibiting superoxide, singlet oxygen, hydrogen peroxide, and the hydroxyl radical, and their effects on hydroxyl radical-induced DNA oxidative damage were systematically analyzed in the present study. The results show that, compared with (−)-epigallocatechin gallate (EGCG), TF derivatives were good antioxidants for scavenging ROS and preventing the hydroxyl radical-induced DNA damage in vitro. TF3 was the most positive in scavenging hydrogen peroxide and hydroxyl radical, and TF1 suppressed superoxide. Positive antioxidant capacities of TF2B on singlet oxygen, hydrogen peroxide, hydroxyl radical, and the hydroxyl radical-induced DNA damage in vitro were found. The differences between the antioxidant capacities of four main TF derivatives in relation to their chemical structures were also discussed. We suggest that these activity differences among TF derivatives would be beneficial to scavenge different ROS with therapeutic potential.  相似文献   
33.
简要概述了茶叶的前处理方法和稀土元素质量分数测定的主要方法,包括灰化法、湿法消解法和微波消解等前处理法,以及分光光度法、电感耦合等离子体发射光谱法、电感耦合等离子体质谱法和中子活化法等检测方法。综合比较,在检测不同类型茶叶中稀土质量分数时,微波消解-ICP-MS 技术具有操作简单、准确度高的优点。  相似文献   
34.
湛江市地处祖国大陆最南端,特定的地理位置和气候条件形成了当地独特的茶文化,并彰显出与别地截然不同的文化特征。这种特征在现代社会体现出经济、文化和社会三种价值,可以有效开发利用。  相似文献   
35.
The perceptions of personal and professional identity development from four Black women counselor educators were examined through a collaborative autoethnography methodology. Themes identified include (a) intentionality of code-switching, (b) inextricable identities, (c) fight for and with authenticity, and (d) mutual development of personal and professional identities.  相似文献   
36.
Marginalized communities cannot and do not have decontextualized experiences with how socioscientific issues, such as exposure to COVID-19 as frontline essential workers, high Black infant mortality rates, air pollution leading to respiratory problems, and other issues, affect their communities. As PreK-12 science teachers and teacher educators strive to dismantle oppressive practices in their classrooms and curriculum, it would be helpful to learn from Black women science teachers who have been engaging in anti-racist practices before the racial awakenings of Summer 2020. In this study, three different virtual focus groups, or Sista Circles, were conducted with 18 Black women secondary science teachers. Ranging from 1 to 22 years of experience, Black women teachers across the country and international participants in Canada and Qatar participated in the Sista Circles. From intersectional qualitative analysis and narrative inquiry, the findings of the study reveal that Black women science teachers enact anti-racist science teaching by bringing something new to the community; using NGSS standards within the context of the community; teaching at the intersection of history, culture, and science learning and teaching; and building critical consciousness in the science classroom. Furthermore, the findings of the study have implications for the use of anti-racist frameworks within the context of science education that were authentically the practices of the Black women in the study. This study offers insights into how the critical consciousness of Black women teachers can be represented in the science classroom even in times of nonsupport from peers and administration. The power and necessity of Black women teachers are paramount in science classrooms specifically because of the neutral, apolitical ways science teaching has been approached in the past. The narratives and stories shared here exemplify how Black women science teachers transform science teaching and learning by displaying various acts of Criticality.  相似文献   
37.
To increase participation of students of color in science graduate programs, research has focused on illuminating student experiences to inform ways to improve them. In biology, Black students are vastly underrepresented, and while religion has been shown to be a particularly important form of cultural wealth for Black students, Christianity is stigmatized in biology. Very few studies have explored the intersection of race/ethnicity and Christianity for Black students in biology where there is high documented tension between religion and science. Since graduate school is important for socialization and Black students are likely to experience stigmatization of their racial and religious identity, it is important to understand their experiences and how we might be able to improve them. Thus, we interviewed 13 Black Christian students enrolled in biology graduate programs and explored their experiences using the theoretical lens of stigmatized identities. Through thematic content analysis, we revealed that students negotiated experiences of cultural isolation, devaluation of intelligence, and acts of bias like other racially minoritized students in science. However, by examining these experiences at the intersection of race/ethnicity and religion, we shed light on interactions students have had with faculty and peers within the biology community that cultivated perceptions of mistrust, conflict, and stigma. Our study also revealed ways in which students' religious/spiritual capital has positively supported their navigation through biology graduate school. These results contribute to a deeper understanding of why Black Christian graduate students are more likely to leave or not pursue advanced degrees in biology with implications for research and practice that help facilitate their success.  相似文献   
38.
目的探讨不同种类茶叶中茶多酚对细菌生长的抑制作用。方法提取茶多酚,配成不同浓度的溶液;纸片法测定茶多酚(浓度为140mg/ml、120mg/ml、100 mg/ml、80 mg/ml、60 mg/ml、40mg/ml)对大肠杆菌、金黄色葡萄球菌及枯草杆菌的抑菌作用;比较抑菌效果。结果三种茶叶的茶多酚对供试细菌均有抑制作用,但不同茶叶的茶多酚对细菌的抑制作用不同,不同种类茶叶茶多酚对同一菌种的抑制作用亦不同。结论不同种类茶叶的茶多酚对细菌生长均有一定的作用。  相似文献   
39.
宜昌茶文化的悠久历史、峡州名茶、煮茶名泉、名人诗文、茶风茶俗等资源异常丰富,并显示出地域性、民族性、丰厚性、生态性等鲜明特点,这使得宜昌历史茶文化具有较高的旅游开发价值。  相似文献   
40.
In this article, I examine Barack Obama’s use of collective memory during his 2007 campaign speech in Selma, Alabama. Specifically, I argue that Obama appeals to collective memory to challenge the Black community’s relationship to the past. He reframed the memory of the Civil Rights Movement in a manner favorable to his political aspirations. While this frame was politically expedient, it weakened Black political agency. It robbed the Black community of crucial rhetorical resources used to challenge structural inequalities in society. This article offers insight into the complex relationship between metaphor and collective memory. Specifically, I interrogate the role of metaphor as a crucial site where public memory is formed, disrupted, and rearticulated. Furthermore, I consider the implications of his use of memory for the future of the Black freedom struggle.  相似文献   
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