如何培养学生学习数学的兴趣

学习兴趣在学生的学习中占有重要地位。为了培养学生学习数学的兴趣,教师应充分利用数学的学科特点,合理安排教学内容,灵活运用教学方法,并在学生遇到困难时给予及时的帮助。     

The functionality of female reciprocal calls in the Iberian midwife toad (<Emphasis Type="Italic">Alytes cisternasii</Emphasis>): female-female acoustic competition?

Female midwife toads (genus Alytes) emit highly variable reciprocal calls of unclear function prior to and during courtship. In some species, female-female competition, expressed as physical fighting, has been reported. Males of Majorcan midwife toads (Alytes muletensis) show phonotactic response to female calls, and females of Iberian midwife toads (Alytes cisternasii) respond differently according to the male call characteristics. In this study, I test the hypothesis of female-female acoustic competition as an additional function of female reciprocal calls. Playback tests indicate that female calls are not clearly involved in female acoustic competition in the Iberian midwife toad, therefore female calls could be directed at males rather than towards competitive females.     

粉煤灰对矿井水中重金属离子的吸附研究

本文通过静态热力学实验的方法，研究了粉煤灰对矿井水中Ｐｂ＾２＋，Ｚｎ＾２＋，Ｃｕ６２＋等重金属离子的吸附性能。着重分析了ＰＨ值，吸附时间，粉煤灰活化程度等因素对其吸附能力的影响。     

江苏省环保信访演变趋势与对策研究

以江苏省为例,着重分析环保信访演变的特点和发展趋势以及产生的主要原因,提出了今后进一步加强环保信访工作的对策措施。     

Gamergates in the myrmicine genus <Emphasis Type="Italic">Metapone</Emphasis> (Hymenoptera:Formicidae)

Gamergates (i.e. mated reproductive workers) are mostly known from ant species within the Ponerinae. We report here the discovery of gamergates in two species of the subfamily Myrmicinae. Until now, mated reproductive females in colonies of myrmicine species have been considered morphologically distinct from the worker caste. However, in two species of the myrmicine Metapone (Metapone madagascarica and a newly discovered, not yet described Metapone species) all workers have six ovarioles and a spermatheca; and some of them are mated. There are no morphological differences between mated and non-mated workers. Field observations and laboratory studies indicate that colonies of the Metapone species can reproduce with gamergates only.     

Vocal acrobatics in a Chinese frog, <Emphasis Type="Italic">Amolops tormotus</Emphasis>

Although amphibians are highly vocal, they generally emit only a limited number of acoustic communication signals. We report here the extraordinarily rich vocal repertoire of Amolops tormotus, a ranid species in China. These frogs produce countless vocalizations, some of which share features of birdsong or primate calls, e.g., ultrasonic frequency components, multiple upward and downward FM sweeps, and sudden onset and offset of selective harmonic components within a call note. Frame-by-frame video analysis of the frog's calling behavior suggests the presence of two pairs of vocal sacs that may contribute to the remarkable call-note complexity in this species. Electronic supplementary material to this paper can be obtained by using the Springer LINK server located at http://dx.doi.org/10.1007/s00114-002-0335-x.     

压缩空气中微量油测定方法的现状与进展

近年来，压缩机制造行业已把压缩空气中微量油浓度作为对压缩机性能评价的一项重要指标。因此，对压缩空气的含油量测定工作越来越得到重视。在制造类企业，压缩空气在生产中有广泛的用途，其对压缩空气的品质有不同的要求。在此介绍了压缩空气中微量油浓度常用的测定方法。包括样品的采集和预处理、标准油的制备以及具体的分析检测手段。     

浅谈水质在线监测仪器的维护与质量控制管理

通过对水质自动监测系统的日常维护与质量控制管理，从水质自动监测系统的维护、室内外质量控制管理、综合分析与控制管理等方面进行分析，提出了保证自动监测系统准确性控制措施，为水质自动监测系统管理提供参考。     

Inventory of emissions from major air pollutant categories in Turkey

In this study, an inventory of air pollutant emission estimates from major air polluting sources in Turkey for period between 1985 and 2005 with 5-year intervals were estimated. Inventory covers anthropogenic sources of five major air pollutants of particulate matter, sulfur dioxide, carbon monoxide, nitrogen oxides and non-methane volatile organic compounds. Their break-down with respect to main activity sectors were shown and their distribution by the largest industrial source categories were worked out as annual estimates. This inventory and its analysis point to serious environmental implications of air pollutants and a need to develop a policy plan for reducing these emissions.     

妨碍国有工业企业推行清洁生产的几个问题

分析不利于国有工业企业推行清洁生产的六方面问题：认识偏差，缺乏激励机制，缺乏足够的资金，技改中新技术含量低，缺乏人才和政府执行力度不够，结合实际情况初步探讨解决办法。