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171.
美国化学会及其期刊的编辑出版 总被引:10,自引:1,他引:9
简要介绍美国化学会及其出版机构的宗旨、服务、发展规划,以及编辑出版规章制度.详细分析美国化学会出版期刊的情况.主要从创刊时间、办刊宗旨、刊期、SCI影响因子、期刊出版总页码等方面分析其各种期刊在国际上的影响力.从期刊的单价、捆绑售价以及网络本售价对期刊进行价格方面的分析.以<美国化学会会志>为例,详细分析期刊稿件的来源情况、稿件的处理情况、编辑人员情况、审稿过程和编辑加工过程,以及编辑出版自动化等. 相似文献
172.
把原来分散的无机化学、有机化学、分析化学和物理化学四大化学实验室整合为基础化学实验教学中心,实现优质资源的共享;改革原有的实验教学体系,构建理科、工科和农科类三大实验模块;改变传统以验证性实验为主的单一实验内容,增设了综合性、设计性、创新性和研究探索性实验;重视实验教学队伍的建设,鼓励高学历、高职称的教师进入实验教学中心担任实验指导教师,提高实验教学质量。 相似文献
173.
化工原理是研究流体流动规律和化工类产品后处理的一门学科,这门学科主要研究化学反应的载体——设备,这门课的学习效果与后续专业课程的学习密切相关.笔者结合自己的教学经历,从主观性、教学方法、培养学生工程意识三个方面探讨如何提高化工原理学习效果. 相似文献
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The preservation of early 20th century, late 19th century albumen prints is of great concern to collection managers and conservators of photographic materials. Attenuated Total Reflection Fourier Transform Infrared (ATR-FTIR) spectroscopic imaging is presented for the first time as analytical methodology for the study of albumen photographs. This paper shows the feasibility of obtaining FTIR images of samples from albumen photographs with a high spatial resolution using a Ge ATR objective coupled with an infrared microscope. The improved spatial resolution compared to FTIR images obtained by the reflection method is due to the high refractive index of the ATR crystal, which gives a high numerical aperture and hence, a higher spatial resolution. The technique reveals detailed information on the organic functional group distribution in the individual layers of embedded cross sections and is used complementary to visual microscopy and scanning electron microscopy/energy dispersed X-ray spectroscopy. The main results of the study are discussed with regard to their historical and artistic significance, and they are compared with data from historical and conservation literature. 相似文献
177.
Maria Pia Riccardi Marco Lezzerini Federico Car Marco Franzini Bruno Messiga 《Journal of Cultural Heritage》2007,8(4):350-360
Two different analytical approaches have been taken into account to investigate the role of Si-rich phases in enhance hydraulic reactions of bedding mortar mixtures from San Lorenzo Church in Milan (Northern Italy) and from the Medicean Aqueduct in Pisa (Central Italy). In the first case, mortars show clear hydraulic type reactions in the form of coronal layers between the reacting additive and the binder mass. In the second one, the hydraulic reactions do not develop visible mineral phases and processes have been inferred from chemical, mineralogical analyses and mass balance calculation. The microstructural studies not always are sufficient to understand the complex dynamics of reaction attained during pre-industrial manufacturing processing of mortars and related binders. In fact, if the reacting raw materials are fine-grained and/or have remarkable chemical reactivity, no relicts are preserved by mortar microtextures. 相似文献
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David Zahradnik Daniel Jandacka Roman Farana Jaroslav Uchytil Joseph Hamill 《European Journal of Sport Science》2017,17(2):241-248
Landing with a low knee flexion angle after volleyball block jumps may be associated with an increased risk of anterior cruciate ligament (ACL) injury. The aim of the present study was to identify the types of volleyball landings after blocks where the knee flexion angle is found to be under a critical knee flexion angle value of 30° at the instant of the first peak of the ground reaction force (GRF). Synchronized kinematic and kinetic data were collected for each trial. T-tests were used to determine if each knee flexion angle at the instant of the peak GRF was significantly different from the critical value of 30°. A repeated measures ANOVA was used to compare knee flexion angle, time to first peak and the magnitude of the first peak of the resultant GRF and knee stiffness. Significantly lower knee flexion angles were found in the “go” landing (p?=?.01, ES?=?0.6) and the “reverse” landing (p?=?.02, ES?=?0.6) only. The results for knee flexion angle and GRF parameters indicated a significant difference between a “reverse” and “go” and other types of landings, except the “side stick” landing for GRF. The “reverse” and “go” landings may present a risk for ACL injury due to the single-leg landing of these activities that have an associated mediolateral movement. 相似文献
180.
Cristine Lima Alberton Stephanie Santana Pinto Gabriela Neves Nunes Douglas Guerreiro dos Santos Rau Paula Finatto Amanda Haberland Antunes 《European Journal of Sport Science》2017,17(8):1013-1020
The aim of the present study was to compare the peak anterior–posterior (Fy) and medio–lateral (Fx) ground reaction forces (GRFs) of women performing stationary running at different intensities in aquatic and dry land environments. Fourteen young women performed the stationary running exercise at three cadences (first ventilatory threshold, second ventilatory threshold and maximum effort, as determined during exercise in water) in aquatic and dry land environments. Two-way repeated measures ANOVA was used to analyse the data (α?=?.05). As a result, significantly lower peak Fy anterior, Fy posterior, Fx medial and Fx lateral values were observed for the aquatic environment, except for the Fy posterior at the first ventilatory threshold. Significant differences were observed between cadences in the peak Fy anterior, Fy posterior, Fx medial and Fx lateral values, with higher values for the cadence corresponding to maximum effort compared to the first ventilatory threshold, except for the Fy posterior and Fx medial in the aquatic environment. The results indicate that the horizontal GRFs are reduced in the aquatic environment and depend on the intensity of stationary running exercise performance. 相似文献