侧析我国的学术环境——对诺贝尔奖困惑的反思

诺贝尔自然科学奖是比较公正的,但政治对科学发展的影响又是现实的。我国之所以未曾问津诺贝尔自然科学奖,在很大程度上是由于政治环境影响了基础研究的学术自由和学术交流。     

Paleotemperature changes ver the past 3000 years in eastern Beijing, China:A reconstraction based on Mg/Sr records in a stalagmite

The Mg/Sr ratio in a stalagmite, which is directly proportional to DMg/Ca, the solid-liquid distribution coefficient of Mg, is proposed as a geochemical thermometer to estimate paleotemperature changes. The paleotemperature changein eastern Beijing over the past 3000 years has been reconstructed by using this thermometer in the stalagmite ZFFS-1 from Jingdong Cave. The records can be divided into two periods: 3000-2000 aBP, cool and wet, the air temperature averaging 9.8℃; and 2000 aBP-present, hot and dry, the air temperature being 1℃ higher than the mean value (11.7℃) of the past 3000 years. During 500-200 aBP, the air temperature was about 1.2℃ lower than that of the present, corresponding to the Little Ice Age in Europe. Like δ18O and δ13C, Mg/Sr (or DMg/Ca) reflects an obviously warming trend of the past 200 years. These results are supported by historic records.     

包头市中小学教师基于信息技术环境的专业研修情况调查

“包头地区校本培训中信息技术资源的开发与利用”课题组于2005年4月在包头市124所中小学的350名教师中进行了“基于信息技术环境下的专业研修情况”调查，结果显示：包头市中小学的现代信息技术条件已具备一定基础。绝大多数学校和教师比较重视信息技术对于教育教学及教师专业发展的作用，初步形成了使用信息技术的环境;具备了使用信息技术的一定能力，教育信息技术与教学、与教师专业研修的联系日趋紧密。存在的主要问题是：薄弱学校的信息技术条件差距较大;相当数量的教师接触的信息资源有限；好多教师对电脑的更多功能不了解、不熟悉；网络利用率偏低，而且不同学段、不同条件、不同性别、不同学科教师的使用情况存在较大差异。     

地理学元研究:地理"关系"的基础、类型和度量

科学的研究正向着广度与深度发展,地理学也不例外。因此,有必要对地理学研究中的不同层次、同一层次之间所存在的不同关系进行一定的梳理,文章拟从系统论视角出发,浅析了地理学研究中的不同层次、同一层次之间所存在的各种关系。     

本溪市生态环境主要问题及防治对策的探讨

本文在本溪市生态环境现状调查的基础上,阐述了生态环境现状,研究其变化原因,分析自然因素和人为开发带来的生态环境问题,并提出相应的防治对策。     

Characteristics of strontium isotopes and their implications in the Qixing Cave of Guizhou,China

The strontium isotopic compositions (87Sr/86Sr) of samples including soils, bedrock, soil waters, drip waters and their corresponding speleothems in the Qixing Cave (QXC), Guizhou Province, China, were systemically measured and analyzed. The results indicate that there are significant Sr isotopic differences among samples. The mean 87Sr/86Sr ratios in drip water for the samples 1#, 4# and 9# were 0.709568, 0.709139 and 0.708761, respectively, which possibly result from different flow paths, residence times, and other hydrogeological processes in the unsaturated zone overlying QXC. Meanwhile, levels of 40.8%, 57.6% and 72.4% of Sr in drip waters for 1#, 4# and 9#, respectively, were derived from bedrock dissolution, which was calculated by the mixture model of the two end-members (soil and bedrock). There is, however, no positive correlation between the relative proportion from bedrock dissolution (δ13C value is 1.8‰) and drip water δ13CDIC values. The mean drip water δ13CDIC value in 1# is the heaviest (–4.5‰) with the lowest contribution rate of bedrock dissolution, whereas the value in 9# is the lightest (–9.3‰) with the highest contribution rate of bedrock dissolution. The proportion from host rock dissolution in 4# is higher than that in 1# and lower than that in 9#, while its mean drip water δ13CDIC value (–8.6‰) is higher than that of 9# and lower than that for 1#. This suggests that the prior calcite precipitation (PCP) processes in the unsaturated zone overlying the cave are responsible for the δ13CDIC value differences between different drip waters, and not bedrock dissolution. Furthermore, this study also demonstrates that the 87Sr/86Sr ratios of speleothems in the 1# and 4# mainly reflect the variation in the relative proportions from the soil system (soil water) and bedrock dissolution overlying the cave. It is, therefore, feasible to use the strontium isotopic signals of speleothems as an indicator for soil chemical weathering intensity, and consequently as a monsoon proxy in the study area.     

基于EKC假说的经济发展与自然保护区关系分析

 利用计量经济学模型对我国各省的自然保护区面积与经济发展、人口密度的关系进行了分析。结果表明,我国自然保护区的发展符合环境库兹涅茨曲线假说,变化的拐点处于人均GDP为2.5万~3.2万元之间。仅北京、天津、上海、浙江与江苏已越过拐点,广东、山东、辽宁、内蒙古和福建处于拐点区间内,甘肃、四川、青海与吉林虽然没有越过拐点,但自然保护区建设情况较好,而海南,贵州的自然保护区面积偏低。     

温室模糊控制系统设计

针对温室环境控制的特点,介绍了温室控制系统的硬件组成,重点介绍了温度和相对湿度的模糊控制推理机制,给出了执行机构的模糊控制规则.测试结果表明了本控制方案是有效的.     

网络环境下《商务英语会话》教学模式探索

本研究以现代英语教学理论为依据,在分析商务英语会话教学现状和课程特点的基础上,提出了基于多媒体网络环境下的"课前引导+课堂教学(多媒体商务体验模式)+网络自主学习和交互管理平台+学生档案袋"商务英语会话教学模式。     

重庆市废旧手机电池回收现状调查及利用对策

手机废旧电池作为高科技垃圾,由于含有许多重金属有毒元素,如果没有采取相应的处理措施,必将对人类居住以及生态环境造成伤害.重庆作为三峡库区和西部开发的核心城市,怎样加强对手机电池固体废物的科学管理以及回收利用科学决策,不仅关系到危险固体废物的科学管理,同时也关系到三峡库区的生态环境和人民的身体健康.为了协助政府出台关于回收利用废旧手机电池这一政策,该研究主要通过对目前手机使用人群就废旧手机电池的处置与回收进行了市场调查、统计,针对重庆市废旧手机电池的处理现状,提出了目前重庆市废旧手机电池固体废物的管理措施与科学的回收利用和处置对策.