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101.
Elena Kozlova 《Slavic & East European Information Resources》2013,14(2-3):188-191
Since 1994, the National Library of Russia has accepted electronic media according to the federal law On the Obligatory Copy of Documents, which established the system of legal deposit in Russia. The Scientific-Technical Center “Informregistr” is responsible for collecting legal deposits of electronic media and provides regular analysis of the National Library's collection of electronic editions. The results of these analyses are given in this article. Bibliographic records of deposited electronic media are available online in the electronic catalog Russian Electronic Editions. Catalog data are used to evaluate the characteristics of electronic editions and publishers. Acquisitions librarians use this catalog as a national bibliographic resource for adding electronic editions to their collections. 相似文献
102.
张媛 《包头职业技术学院学报》2013,(4):44-46
元散曲大家关汉卿套曲[南吕·一枝花]《不伏老》,一直受到诸多学者的关注,其中“铜豌豆”式的曲笔自画像既是学者们研究关汉卿的重要资料,也是后人了解元初散曲作家的境界、心态、曲风的可贵文献. 相似文献
103.
Yupeng Cui Xiaoyan Liu Xiaoran Liu Jian Wu Minghua Zhao Jingping Ren 《Journal of sports sciences》2013,31(4):363-371
Abstract The aim of this study was to examine the exercise workload of the 3rd Series of National Broadcast Calisthenics for Elementary and Middle School Students. Altogether, 120 students aged 11–17 years were randomly selected from elementary and middle schools to participate in the study. Each participant performed a cycle ergometer test to obtain maximum oxygen uptake ([Vdot]O2max) and maximum heart rate values. In the laboratory, oxygen uptake ([Vdot]O2), metabolic equivalents (METs), and heart rate were recorded continuously throughout a calisthenics session performed by the participants. Ratings of perceived exertion (RPE) were also recorded. Throughout the calisthenics session, mean percentage of [Vdot]O2 reserve varied from 30.7% to 41.2%, mean percentage of heart rate reserve from 39.0% to 56.9%, and mean RPE from 9.0 to 10.4. The mean energy cost during most of the segments across the four routines of calisthenics was significantly higher (P < 0.05) than 3.0 METs. In conclusion, the exercise workload of the 3rd Series of National Broadcast Calisthenics for Elementary and Middle School Students session varied from low to moderate. As part of a school-based physical activity intervention project, calisthenics would help to promote an active lifestyle and health in children and adolescents. 相似文献
104.
Henry J. Montoye Thomas Ayen Richard A. Washburn 《Research quarterly for exercise and sport》2013,84(3):250-253
Abstract The purpose of this study was to assess the relationship between physiological and anthropometrical variables and 15-km time trial (TT) cycling performance time. Twenty-two competitive cyclists averaged 59.7 ml · kg–1 · min–1 for maximal oxygen consumption ([Vdot]O2max), 42.8 ml · kg–1 · min–1 for anaerobic threshold (AT), and 23.5 min for the 15 km TT race. The relationship between [Vdot]O2max and cycling performance time was r = – 0.68, (p < .01) while the correlation between AT and performance time was r = – 0.93, (p <.01). Applying stepwise multiple regression analysis, the two-variable model of the AT and the body circumference ratio, thigh+calf:arm+chest, was found to correlate highly with cycling performance time (r =0.966). It was concluded that the successful cyclists are characterized by the ability to consume large amounts of oxygen prior to ventilatory changes associated with the anaerobic threshold as well as a larger lower to upper body circumference ratio which may favorably decrease wind resistance while cycling. 相似文献
105.
梁伟华 《桂林师范高等专科学校学报》2009,23(4):25-33
龙州县位于广西壮族自治区西南边陲,与越南接壤。龙州蔗园话在清朝中叶由南宁传入,至今200多年。语音特点跟桂南平话的一般特征相合。同音字汇收3400字。 相似文献
106.
本文从山西祁县话中常用代词[nja33]与"人家"的语法、语用及修辞等方面的共同点出发,对其进行语音上的关联,并得出了[nja33]即为"人家"的古合音的遗留. 相似文献
107.
David Foster Filippo Gilardi Wei Song Dave Towey Andrew White 《Teachers and Teaching》2018,24(7):840-853
This article reports an undergraduate software engineering project in which, over a period of 2 years, four student teams from different cohorts developed a note-taking app for four academic clients at the students’ own university. We investigated how projects involving internal clients can give students the benefits of engaging in real software development while also giving them experience of a student-staff collaboration that has its own benefits for students, academics, and the university more broadly. As the university involved is a Sino-Foreign university located in China, where most students are Chinese and most teaching staff are not, this ‘student as co-producer’ approach interacts with another feature of the project: cultural distance. Based on analysis of notes, reports, interviews, and focus groups, we recommend that students should be provided with communicative strategies for dealing with academics as clients; universities should develop policies on ownership of student-staff collaborations; and projects should include a formalised handover process. This article can serve as guidance for educators considering a ‘students as co-producers’ approach for software development projects. 相似文献
108.
以4-羟基环孢素转化菌Nonomuraea dietziae为出发菌,采用紫外-氯化锂复合诱变的方法,筛选得到一株产量达208 mg/L的稳定遗传菌J263,较出发菌164 mg/L的产量提高26.8%。在此基础上,采取单因素法和响应面法针对诱变菌的发酵培养基碳氮源进行系统优化,并对金属离子的添加进行考察。最终获得最佳的培养基配方(甘油26.5 g/L,糊精11.6 g/L,蛋白胨9.7 g/L,酵母浸粉3.5 g/L,大豆饼粉15.0 g/L,大豆油2.0 g/L,硫酸镁0.40 g/L,硫酸锰0.010 g/L,钼酸铵0.010 g/L)。在最优化条件下,4-羟基环孢素产量可达324 mg/L,较出发菌提高97.6%。 相似文献
109.
Heteroheptacene-based acceptors with thieno[3,2-b]pyrrole yield high-performance polymer solar cells
Zhenghui Luo Ruijie Ma Jianwei Yu Heng Liu Tao Liu Fan Ni Jiahao Hu Yang Zou Anping Zeng Chun-Jen Su U-Ser Jeng Xinhui Lu Feng Gao Chuluo Yang He Yan 《国家科学评论(英文版)》2022,9(7)
Rationally utilizing and developing synthetic units is of particular significance for the design of high-performance non-fullerene small-molecule acceptors (SMAs). Here, a thieno[3,2-b]pyrrole synthetic unit was employed to develop a set of SMAs (ThPy1, ThPy2, ThPy3 and ThPy4) by changing the number or the position of the pyrrole ring in the central core based on a standard SMA of IT-4Cl, compared to which the four thieno[3,2-b]pyrrole-based acceptors exhibit bathochromic absorption and upshifted frontier orbital energy level due to the strong electron-donating ability of pyrrole. As a result, the polymer solar cells (PSCs) of the four thieno[3,2-b]pyrrole-based acceptors yield higher open-circuit voltage and lower energy loss relative to those of the IT-4Cl-based device. What is more, the ThPy3-based device achieves a power conversion efficiency (PCE) (15.3%) and an outstanding fill factor (FF) (0.771) that are superior to the IT-4Cl-based device (PCE = 12.6%, FF = 0.758). The ThPy4-based device realizes the lowest energy loss and the smallest optical band gap, and the ternary PSC device based on PM6:BTP-eC9:ThPy4 exhibits a PCE of 18.43% and a FF of 0.802. Overall, this work sheds light on the great potential of thieno[3,2-b]pyrrole-based SMAs in realizing low energy loss and high PCE. 相似文献
110.
本文介绍了室温离子液体的独特性质,品种繁多,应用领域十分广泛,涉及学科众多。近年来,国内外研究蓬勃发展,将成为绿色化学发展的前沿。 相似文献