提高GPS定位精度的群调度滤波算法*

为解决现行安全生产科技领域中全球定位系统（GPS）/惯性导航系统（INS）融合系统容易产生较大时变误差的关键问题，满足GPS定位信号的精度和信号数据处理时间的要求，提出1种群调度滤波算法，通过实验仿真，分别与模糊算法、机器学习算法及卡尔曼滤波网络算法进行比较研究。结果表明:群调度滤波算法兼顾了定位精度与数据处理时间，具有较大优势，可在航空安全、船舶安全、应急监测、灾后抢险等安全科技领域广泛应用。     

A path analysis model for explaining unsafe behavior in workplaces: the effect of perceived work pressure

Background. Unsafe behavior is closely related to occupational accidents. Work pressure is one the main factors affecting employees’ behavior. The aim of the present study was to provide a path analysis model for explaining how work pressure affects safety behavior. Methods. Using a self-administered questionnaire, six variables supposed to affect safety employees’ behavior were measured. The path analysis model was constructed based on several hypotheses. The goodness of fit of the model was assessed using both absolute and comparative fit indices. Results. Work pressure was determined not to influence safety behavior directly. However, it negatively influenced other variables. Group attitude and personal attitude toward safety were the main factors mediating the effect of work pressure on safety behavior. Among the variables investigated in the present study, group attitude, personal attitude and work pressure had the strongest effects on safety behavior. Conclusion. Managers should consider that in order to improve employees’ safety behavior, work pressure should be reduced to a reasonable level, and concurrently a supportive environment, which ensures a positive group attitude toward safety, should be provided. Replication of the study is recommended.     

Conservation mycology in Australia and the potential role of citizen science

Fungi are undoubtedly important for ecosystem functioning; however, they have been omitted or given scant attention in most biodiversity policy documents, management plans, and formal conservation schedules throughout the world. This oversight may be due to a general lack of awareness in the scientific community and compounded by a scarcity of mycology‐associated curricula at the tertiary level and a lack of mycologists in research institutions. Although molecular techniques advance the systematic cataloging of fungi and facilitate insights into fungal communities, the scarcity of professional mycologists in the environmental sciences hampers conservation efforts. Conversely, citizen science initiatives are making significant contributions to the mycology discipline by increasing awareness and extending the scope of fungal surveys. Future research by professional and amateur mycologists into the distribution of fungi and their function in ecosystems will help identify wider and more effective conservation goals.     

新民城市居民头发重金属含量测定及相关分析

文章采用电感耦合等离子体原子发射光谱法(ICP-AES)及原子荧光光谱法(AFS)对辽宁省新民市城市居民不同年龄、性别群体头发中镉(Cd),铅(Pb),汞(Hg),砷(As)等重金属含量进行了测定,比较并分析了人发中各种重金属含量水平及与年龄、性别的关系。结果表明,新民市城市居民整体群体头发中镉,铅,砷,汞等4种重金属平均含量分别为(0.14±0.10),(3.80±2.43),(0.29±0.17),(0.39±0.21)mg/kg,均在中国居民头发中重金属含量正常值上限以下。回归分析表明,头发中所测定的重金属中只有金属Hg含量变化与年龄之间存在线性关系(R2=0.71);单因素方差(One-way ANOVA)分析表明,不同年龄群体间Cd,Pb,Hg,As等重金属含量无显著性差异(p>0.05);皮尔逊相关分析表明各重金属含量与年龄、性别之间无显著相关性(p>0.05)。     

废偕胺肟型螯合树脂再生工艺及吸附性能研究

为了解决废弃螯合吸附树脂堆积对环境造成污染,在参考了原树脂合成路线的基础上,设计出了资源化处理该树脂的方法。在二乙胺溶剂中,以废偕胺肟型螯合树脂为原料,加入羟胺试剂,使废树脂发生偕胺肟化反应改性为偕胺肟基聚丙烯腈-二乙烯基苯,实现了废树脂的再生。探讨了废螯合树脂改性工艺及吸附性能,在实验中单因素考察了反应温度、反应时间、二乙胺浓度、盐酸羟胺浓度以及NaOH浓度等因素对偕胺肟化反应效率的影响,同时对树脂及二乙胺溶液进行循环使用。结果表明,二乙胺浓度为70%,盐酸羟胺浓度为1.2mol/L,NaOH浓度为2mol/L,反应温度为50℃,反应时间为2h时达到最佳再生综合效能。以Cu(Ⅱ)离子进行吸附效率测试,有效地恢复该种树脂的吸附能力的90%。树脂循环使用四次之后,吸附效率仍能达到60%。傅里叶变换红外光谱(FT-IR)对螯合树脂表征表明,腈基转化成了偕胺肟基团。在废树脂再生的反应过程中,二乙胺溶剂表现为激活剂的作用。     

青海省扎日根结扎群火山岩形成时代及构造背景分析

青海扎日根结扎群火山岩中基性岩以贫硅、钾,高钛、钙,中性岩类以低硅、中钾、钛、钙,酸性岩类以高硅、钾,中钛,低钙为特征.根据Fe*/MgO-TiO2图解上显示出本区火山岩绝大多数火山岩落在岛弧区.微量元素中Th/Nb=0.9>0.11,Nb/Zr>0.04显示出其构造背景为陆-陆碰撞形成的岛弧区.扎日根结扎群火山岩时代Rb-Sr同位素等时线给出的年龄为231±28 Ma 和225±8 Ma,属晚三叠世.另外Sr同位素的初始比值ISr=0.70522±0.00023,小于0.719,表明岩浆(原始)来源于上地幔,并且在上升的过程中受到地壳的混染.     

基于GM(1,1)模型群的阿什河氨氮浓度的预测研究

依据灰色系统理论,以2000年-2009年10年阿什河入江口断面枯水期氨氮浓度构造了一个由6个GM(1,1)模型组成的灰色动态模型群,并运用该模型群对其变化趋势进行了预测分析,得到令人满意的结果。研究表明,灰色动态模型群法能够充分利用近期水质资料信息预测未来水质变化趋势;以模型群统计平均值作为最终预测值,避免了单一灰色模型容易利用不稳定信息的缺陷,使得预测精度更加准确,预测结果更为可信。     

青岛大气气溶胶中氨基化合物的分布特征

氨基化合物是大气气溶胶和雨水中常被检出的一类有机氮化合物,由于其可作为生物生长直接的氮源,因此可能对海洋生态系统产生直接作用.利用2008年1～12月在青岛采集的66个总悬浮颗粒物样品,采用邻苯二甲醛/N-乙酰-L-半胱氨酸柱前衍生高效液相色谱法,分析了其中溶解态(DAC)和颗粒态氨基化合物(PAC)的浓度.气溶胶中DAC浓度为2.4～40.9nmol·m-3,在春季最高,夏季次之,秋季、冬季最低.PAC浓度为0.7～76.1nmol·m-3,呈现春季冬季秋季夏季的变化趋势.不同季节氨基化合物的组成不同.依据气团的后向轨迹,气溶胶样品可分为受北方陆源、南方陆源和海洋源影响,DAC和PAC在受南方陆源影响的气溶胶中浓度最高,北方陆源次之,海洋源气溶胶中最低.不同来源的气溶胶中氨基化合物的组成不同,蛋白质类氨基化合物对总氨基化合物的贡献在海洋源气溶胶中最高,在南方源气溶胶中最低.     

纤维素胺基树脂的制备及脱色性能评价

用氯化亚砜改性微晶纤维素,利用二乙烯三胺对氯化纤维素进行胺基取代制得纤维素胺基树脂。通过正交试验确定纤维素胺基树脂的最佳制备条件;红外分析以及X-衍射可知:氯化纤维素改性取代胺基得到纤维素胺基树脂。纤维素胺基树脂有较好的脱色功能。对甲基橙脱色条件为:吸附时间6 h,吸附温度为30℃,甲基橙初始浓度取为20 mg/L,树脂投加量为0.02 g。     

Improved speciation of dissolved organic nitrogen in natural waters: amide hydrolysis with fluorescence derivatization

The objective of this study was to improve primary-amine nitrogen (1°-N) quantification in dissolved organic matter (DOM) originating from natural waters where inorganic forms of N, which may cause analytical interference, are commonly encountered. Efforts were targeted at elucidating organic-N structural criteria influencing the response of organic amines to known colorimetric and fluorescent reagents and exploring the use of divalent metal-assisted amide hydrolysis in combination with fluorescence analyse...