Fe(Ⅲ)-H2O2-甲基紫体系催化褪色光度法测定痕量铁(Ⅲ)

研究了Fe(Ⅲ)在酸性介质中催化双氧水甲基紫体系的氧化褪色反应,提出一种测定痕量Fe(Ⅲ)的新方法,体系的最大吸收波长为566nm,Fe(Ⅲ)含量在4～12μg*ml-1符合朗伯-比耳定律,回归方程为ΔA=0.00775C+0.05,相关系数γ=0.9930,最低检出限为2.75×10-7g*ml-1,相对标准偏差为1.83%,结果令人满意.     

Child abuse screening: Implications of the limited predictive power of abuse discriminants from a controlled family study of pediatric social illness

The predictive value of a child abuse screening instrument on unselected populations is illustrated for varying hypothesized levels of child abuse prevalence in order to demonstrate outcome of a hypothetical national screening program. At any level of application, the prediction of false positives and false negatives suggests a low practical utility for an unacceptably high social cost.     

Visual and auditory memory: Relationships to reading achievement

In two experiments, visual and auditory memory was tested for good and for poor readers from the upper elementary grades. Under experimenter-blind conditions, no reading group differences existed for single mode presentation in recognition frequency or recognition latency. With a multimodal presentation, latencies for poor readers were similar to those for the single mode presentation. Good readers, however, had significantly faster latencies with multiple input. Generally, results supported dual coding and self-terminating memory search hypotheses for previously encoded stimuli. Implications of the latency differences between reader groups were discussed with respect to the reading process and reading theory.     

CONSTRUCTION AND EXPRESSION OF BACTERIORHODOPSIN MUTANT IN HALOBACTERIUM HALOBIUM

ＣＯＮＳＴＲＵＣＴＩＯＮＡＮＤＥＸＰＲＥＳＳＩＯＮＯＦＢＡＣＴＥＲＩＯＲＨＯＤＯＰＳＩＮＭＵＴＡＮＴＩＮＨＡＬＯＢＡＣＴＥＲＩＵＭＨＡＬＯＢＩＵＭＷａｎｇＪｉａｎ（汪俭）；ＭｅｉＱｉ（梅祺）；ＬｕＣｈｕｎｌｉｎ（卢春林）（ＤｅｐａｒｔｍｅｎｔｏｆＢｉ...     

居民对H7N9型禽流感认知与应对的现状及对策思考——基于政府危机管理模式

综述我国居民对H7N9型禽流感认知与应对现状以及政府干预现状,分析其存在的不足,做出提高我国居民对H7N9型禽流感认知与应对能力和政府干预水平的对策思考,即"三位一体"模式普及居民H7N9相关知识;优化政府危机管理模式,建立健全应急机制;严格控制媒体信息准入,提高媒体人社会责任感。     

古汉语谦敬称谓词类的词性探讨

古汉语谦敬称谓词类的词性，有两种不同的看法：代词说和名词说。通过全面考察，我们发现它们的语法功能、语义演变、代替作用等，都同名词基本相同，而与代词相距较远。因此，它们应该归属于名词。仅仅因为其代替作用就把它们归为代词是不恰当的，我们应该考虑其整体特点。     

弯管列当的补充描述

The name Hydrocotyle chinensis (Dunn) Craib (Apiaceae) used in 《Flora Reipub- licae Popularis Sinicae》 has had a confused history and is also a later homonym of H. chinesis L. Hydrocotyle shanii is proposed as a new name for this species to commemorate ProfessorRen-hwa Shan's lifelong study of the Apiaceae.     

快速氢原子与原子氦碰撞截面计算

应用量子力学第一玻恩近似和氢原子与氦原子的解析波函数,计算了它们弹性碰撞和各种非弹性碰撞截面。     

燃料电池

论述了燃料电池的原因,详细分析了燃料电池的特点和类型,并对其发展前景作了展望。     

Who contributes voluntarily to OSS? An investigation among German IT employees

Based on newly assembled survey data, we analyze which individual characteristics of IT employees are associated with the willingness to participate voluntarily in Open Source Software (OSS) projects. We find that, contrary to common expectations, formal educational attainment is not positively associated with the probability or level of OSS contributions. The group of university dropouts, however, does show a particularly high probability of working on such projects. Furthermore, we obtain the striking and novel finding that work-related OSS activities play an important role in determining voluntary OSS contributions during leisure time. Although one has to be cautious regarding the direction of causality, we interpret this as evidence of career-oriented motives in voluntary OSS contributors. The finding is also reinforced by our more specific analysis of the importance of such motives in determining the actual effort invested in OSS projects.