膨润土作为药用赋形剂对Pb~(+2),Cd~(+2),Cr~(+6)离子的吸附研究

本文选用吉林省九台、小梨河、净月产地的膨润土为原料,测试了不同粒级的膨润土对Pb 2、Cd 2、Cr 6离子的吸附时间、吸附温度、吸附量,同时,又在模拟人胃条件下进行了试验,结果证实膨润土可以作为药用赋形剂。     

Biochemical Characterization of Refractory Organic Substances

The characterization of refractory organic substances (ROS) is very complicated because of their heterogeneous structure. Size-exclusion chromatography with continuous detection of dissolved nitrogen (LC-DN), dissolved organic carbon (LC-DOC), and UV-absorbance (LC-UV) is a very useful analytical tool for the characterization of changes of ROS in natural aquatic systems and in technological treatment. The effect of natural, oxidative, and biochemical processes on formation and removal of ROS is described. Additionally the role of hydrolysable carbohydrates in the composition of ROS is presented.     

GC/MS-Nontargetanalytik zur Aufklärung einer organischen Grundwasserkontamination. Teil I: Probennahme – Analytik – Identifikation der organischen Verbindungen

GC/MS Nontarget Analysis to Examine an Organic Groundwater Contamination. Part I: Sampling – Analysis – Identification GC/MS nontarget analysis is a combination of an extraction sequence and a GC/MS analysis without standards. The extraction sequence should enrich a wide range of organic substances with different chemical and physical properties. The GC/MS analysis without standards evaluates the total chromatogram whereas the possibilities of compound identification are limited. This kind of view is suited very well if the task of examinations are unknown organic contaminations and the conventional target analysis has to be expanded to a large number of compounds with the uncertainty of detecting the main contaminants. The extraction sequence is similar to the EPA 625 analysis of base/neutral and acid extractable organic compounds. Basis are liquid extraction and solid-phase extraction at different pH values. This extraction procedure covers approximately 30 % of total organic carbon of these groundwater samples from a contaminated area near a low temperature carbonization plant. Relevant groups of organic compounds analyzed in the contaminated groundwater or in the reference sample are substituted aromatics, phenols, benzoamines (anilines), and derivates of benzothiophene. Differences in the trace substance mixtures between the contaminated samples and the reference sample are demonstrated by applying modern graphical methods.     

Morphological Investigations in the River Odra

Since 1992, the Federal Institute of Hydrology (Bundesanstalt für Gewässerkunde – BfG) performs morphological investigations in the river Odra downstream from the confluence of the river Neiße (Nysa Luzycka). The results of these investigations give a clear insight into the morphodynamic behaviour of this part of the river and indicate that on average 380 000 t of suspended solids and 130 000 t of bed load are transported by the river Odra at Hohensaaten per year, with a distinct seasonal variability in the case of suspended solids. Detailed studies on type and composition of the bed substrates have revealed that the river bottom is composed of very fine material: at Ratzdorf already 75 % of the bed material is finer than 2 mm, at Widuchowa almost all of the river bed material consists of sand finer than 0.63 mm. Because of the high sensitivity of the river bottom to discharge increases and the corresponding increases of bottom shear stress sand was found to be the dominating fraction of the suspended load in case of extreme flood events.     

Description of Ecosystem of the Lower Odra and the Odra Estuary

Environmental conditions of the lower river Odra and its estuary show a high variability of chemical and biological parameters, related to the dynamics of the river, its mouth area, the Lake Dabie-Szczecin Lagoon system, and the Pomeranian Bay. Water chemistry, affected by the total sum of industrial, urban, and agricultural pollution discharged from the direct drainage area is discussed. This pollution load influences the composition and ecological structures of terrestrial, frequently unique, phytal communities associated with aquatic areas, phyto- and zooplankton, benthos, fish fauna, and avifauna. The current status of the terrestrial and aquatic ecosystems is described; elements of cultural infrastructure existing within the Lower Odra Valley in Western Pomerania are mentioned as well.     

长三角典型城郊流域溶解性有机质的分子特征:以浙江樟溪为例

溶解性有机质(DOM)在流域水环境中广泛存在,参与各种生物地球化学循环过程。快速的城镇化过程和人类活动显著改变了流域水体DOM含量和特性,从分子层面上解析DOM在流域尺度上的时空分异特征对流域水质管控具有重要的理论和应用价值。以长三角地区樟溪流域为研究对象,依据土地利用和人类活动强度布设采样点,于2022年7月采集水样。结果表明,樟溪流域水体溶解性有机物主要的分子式元素组成为CHO、CHON、CHOS,其中木质素/富羧酸脂环分子类有机物相对占比最高。在子流域空间分布上,人类活动强的子流域CHON、CHONS类型化合物含量更高。选取采样点距城镇距离、距源头距离以及土地利用类型所占采样点缓冲区的比例来表征人类活动的影响。结果表明,流域内DOM杂原子受人类活动强度影响,距源头的距离与水体DOM分子中氮原子的强度加权平均值(N_wa)和CHON化合物百分呈显著正相关,与碳、氢原子和荷质比的强度加权平均值(C_wa、H_wa、m/z_wa)呈显著负相关。CHON分子的相对丰度与林地面积比例呈显著负相关,与农业用地比例呈显著正相关。比较具有典型土地利用类型的水体DOM:典型农田、城镇土地利用类型DOM含有更多独特的CHON分子式,农田DOM在木质素/富羧酸脂环分子区域出现CHON分子式的富集,城镇DOM在脂肪类和木质素/富羧酸脂环分子区域均出现了CHON分子式富集。研究表明在城郊流域中,人类活动显著改变了水体DOM的分子特征,增加了分子多样性,促进了特定分子式的富集。     

2014年于田MS7.3地震对后续余震和远场小震活动的动态应力触发

本文采用离散波数法,计算了2014年于田M_S7.3地震的断层破裂在近场和远场产生的库仑破裂应力变化,并结合地震活动特征,讨论了M_S7.3地震对后续余震活动和远场区域小震活动的动态应力触发作用.结果表明, ① M_S7.3地震产生的库仑破裂应力变化对其西南侧主体余震区的地震活动起到了抑制作用,这可能是本次M_S7.3地震序列余震活动水平不高的主要原因;距主震约30 km的北东方向余震区后续地震活动受到了主震产生的动态和静态应力变化的共同触发作用,动态应力变化峰值为2.78 MPa,静态应力变化为0.80 MPa,这与该区余震较为活跃相一致;距主震约45 km的北部余震区受到动态应力触发作用,应力变化峰值为0.72 MPa. ② M_S7.3地震产生的动态库仑应力变化空间分布呈非对称性,其中北东方向、北部余震分布与动态应力变化正值区存在相关性,从应力变化的角度解释了M_S7.3地震的后续余震空间活动特征. ③ M_S7.3地震在沙雅、伽师地区的远场接收点产生的动态应力变化峰值分别为0.09 MPa、0.1 MPa,对两个区域的小震活动具有动态触发作用.     

关于端基分析法测定壳低聚糖的相对数均分子质量问题的探讨

为使端基分析法更具合理性。文中以铁氰化钾为显色剂。以盐酸氨基葡萄糖和N-乙酰基-D-葡萄糖胺为还原糖的标准品,建立了端基分析法测定低聚糖相对数均分子质量的标准曲线。实验结果证明：通过不同浓度的标准溶液绘制的标准曲线,测得壳低聚糖的相对数均分子质量差别比较大。以凝胶色谱法测定的相对数均分子质量为对照,经分析得：以盐酸氨基葡萄糖为标准品建立的标准曲线方程和以N-乙酰基-D-葡萄糖胺为标准品建立的标准曲线方程更为合理。     

2020-01-19伽师6.4级地震前后视应力变化

柯坪块体中强地震频发,为获得更多的震情判定依据,利用新疆区域地震台网提供的数字地震学波形资料,计算柯坪块体2010~2020年M_L≥3.0地震的视应力值,讨论震源参数的标度关系,并分析柯坪块体5.0级及以上地震和伽师6.4级地震前后视应力的时空变化特征。结果表明,视应力和震级呈正相关关系;柯坪块体5.0级及以上地震前,视应力值在时间和空间上均出现不同程度的高值异常;伽师6.4级地震发生在视应力高值过程中,且震前5个月在震中区出现视应力高值异常。     

基于多源证据估算气候敏感度最新研究进展:IPCC AR6解读

本文依据政府间气候变化专门委员会(IPCC)第六次评估报告(AR6)第一工作组(WGI)报告第七章的内容,详细解读了基于多源证据对气候敏感度的估算,这些证据包括:过程理解、仪器记录、古气候数据和萌现约束。得到的结论是,多源证据支持平衡态气候敏感度(ECS)的中心估计值接近3 ℃,可能区间为2.5～4.0 ℃,非常可能区间为2.0～5.0 ℃;瞬态气候响应(TCR)的最佳估值为1.8 ℃,可能区间为1.4～2.2 ℃,非常可能区间为1.2～2.4 ℃。与之前历次IPCC评估报告相比,AR6关于气候敏感度的估算最为重要的创新之处为,它没有将气候模式结果当作唯一证据,而是仅仅给出第六次国际耦合模式比较计划(CMIP6)结果并与基于多源证据的综合评估结果进行了对比。通过对比发现,CMIP6关于ECS与TCR的平均值均高于第五次国际耦合模式比较计划(CMIP5)和AR6的综合评估结果。相比CMIP6,AR6综合了多个证据线有效地缩小了ECS的不确定范围。