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71.
利用分光光度法测定了潮州产10种野菜中硝酸盐、亚硝酸盐的含量,利用氧化还原滴定法测定了维生素ca含量.结果表明:月光花、决明、铁苋菜和叶下珠的硝酸盐含量低于轻度污染水平(432mg/kg鲜重),亚硝酸盐含量低于无公害蔬菜亚硝酸盐含量的限量标准(44.0mg/kg鲜重),它们属于一级野菜,可以安全食用;鸡矢藤、白勒和苎麻的硝酸盐含量低于785mg/kg,属于中度污染水平,亚硝酸盐含量低于无公害蔬菜亚硝酸盐含量的限量标准,属二级蔬菜范围,不宜生食,煮熟或盐渍可安全食用;鳢肠硝酸盐含量高于785mg/蚝而低于1440mg/kg,亚硝酸盐含量低于无公害蔬菜亚硝酸盐含量的限量标准,维生素C含量高于50mg/100g鲜重,属于三级蔬菜,不可生食和盐渍,可熟食。牡荆和肖梵天花虽然硝酸盐含量很低,但维生素C含量较低,亚硝酸盐含量高于无公害蔬菜亚硝酸盐含量的限量标准,所以不宜食用.  相似文献   
72.
从供给和需求的角度分析了我国农业科技成果推广水平低的原因,通过供求均衡分析,认为农业科技成果推广率的提高必须在刺激农业科技成果有效需求的同时,增加农业科技成果供给,并提出增加农业科技成果的供给和需求的措施建议。  相似文献   
73.
战国秦汉时期的里社与私社   总被引:3,自引:0,他引:3  
近年来长江流域出土的简牍材料表明,战国秦汉时期南方楚地存在着很多里。里皆有其社,社主又有“地主”、“侯土”等异名。围绕着里社的巫术活动十分盛行。从战国至汉代,里、社合一之制基本得到沿续,然而里、社分离的历史趋势已明显存在。西汉晚期,民间百姓在里社(官社)之外另立私社。东汉初年的《序宁祷券》证明了此种私社的存在,西汉中期邗江汉墓的《神灵名位牍》和秦朝末年的周家台秦简《日书》中关于私社的内容,比文献中唯一一条材料(见《汉书.五行志》)要分别提前36年和177年。  相似文献   
74.
This case study is written for instructors of sport management courses focused on ethics and integrity-related issues in team environments. The case highlights the real world example of the University of Waterloo Warriors varsity football that, in 2010, experienced the most significant doping scandal in Canadian university sports history, with a total of nine anti-doping rule violations asserted through the Canadian Centre for Ethics in Sport. This case study also incorporates the findings of an independent review of the Waterloo football program in relation to the use of banned substances, and includes first-hand accounts from Bob Copeland who was the acting director of athletics. These findings are then interpreted in the context of relevant theory related to performance enhancing drugs (PEDs) use. Along with the findings of this review, which included interviews with athletes, coaches, and administrators, the case study provides important insights into ethical decision making processes and leadership structures in a team sport environment. Particular emphasis is placed on the role that individual cognitive antecedents and contextual organizational factors (i.e., policies, leadership, ethical climate, and infrastructure) play in ethical decision-making processes.  相似文献   
75.
This study compared the whole-body movement coordination of pitching among 72 baseball players of various ages and velocity levels. Participants were classified as senior, junior, and little according to their age, with each group comprising 24 players. The velocity levels of the high-velocity (the top eight) and low-velocity (the lowest eight) groups were classified according to their pitching velocity. During pitching, the coordinates of 15 markers attached to the major joints of the whole-body movement system were collected for analysis. Sixteen kinematic parameters were calculated to compare the groups and velocity levels. Principal component analysis (PCA) was conducted to quantify the coordination pattern of pitching movement. The results were as follows: (1) five position and two velocity parameters significantly differed among the age groups, and two position and one velocity parameters significantly differed between the high- and low-velocity groups. (2) The coordination patterns of pitching movement could be described using three components, of which the eigenvalues and contents varied according to age and velocity level. In conclusion, the senior and junior players showed greater elbow angular velocity, whereas the little players exhibited a wider shoulder angle only at the beginning of pitching. The players with high velocity exhibited higher trunk and shoulder rotation velocity. The variations among groups found using PCA and kinematics parameter analyses were consistent.  相似文献   
76.
运用文献资料、教学实验、数理统计等方法,揭示微信平台和移动健身运用(APP)对大学生体质健康水平的影响及其作用机制。结果:1)实验组实验后体质健康各项指标(身高体重除外)均有显著的提升(P<0.05),对照组各指标也均有上升趋势,但无统计学意义(P>0.05);2)实验组实验后各项指标(身高体重除外)显著高于对照组(P<0.05)。结论:1)基于互联网的线上运动干预项目可以有效促进大学生的体质健康水平,可以作为大学生体育锻炼习惯养成及体质健康促进的有效手段;2)线上运动干预项目促进大学生体质健康的作用机制是通过目标设定,自我监测行为,个性化定制与指导,社会互动等强化因素作用的结果。  相似文献   
77.
张世英"万物一体,民胞物与"的哲学-伦理观,主要包括以下几个方面的内容:哲学是追求人与万物一体的境界之学;以"主客二分"和"天人合一"作为人与世界的两种关系;基于真善美统一于万物一体,强调要把道德意识建立在万物一体的本体论基础之上;倡导哲学家应按自己的哲学信念生活,提出要以希望哲学来代替猫头鹰哲学,是一种综合了中西哲学史的积极成果,并对时代的挑战做出了创造性回应的哲学-伦理观。  相似文献   
78.
INTRODUCTION The differential quadrature method (DQM) was proposed by Bellman and Casti as an analogous ex- tension of the quadrature method for integrals (Bellman and Casti, 1971; Bellman et al., 1972). It can be essentially expressed as the values of the de- rivatives at each grid point as weighted linear sums approximately of the function values at all grid points within the domain under consideration. As a distinct numerical solution technique to obtain the initial and/or boundary …  相似文献   
79.
从虚拟制造的形成背景,介绍了虚拟制造的特点、分类;并对虚拟制造的核心技术及理论体系等多方面进行详细阐述。最后就虚拟制造的应用和虚拟制造技术的发展潜力和国内外现状进行系统介绍。  相似文献   
80.
Example based painting generation   总被引:1,自引:0,他引:1  
INTRODUCTION Non-photorealistic rendering (NPR) is a domain of computer graphics that has received more and more attention in the past decade. Different from realistic rendering, NPR concentrates on communicating the main context of an image and explores the rendering effect of the scene with the artistic styles, rather than seeking subtle geometry details and naturally physical attribute. Many research efforts were dedicated to simu- lating the traditional media (Hertzmann et al., 2001…  相似文献   
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