通过胶州湾1991年5月至1994年2月的实测数据的分析,展示了Si∶N比值起因和Si生物地球化学过程,并且建立初级生产力与Si∶N的比值的动态方程。利用非保守性物质Si∶N比值作为湾内水的示踪剂,根据海湾的水交换完成的定义及海湾的充满和放...通过胶州湾1991年5月至1994年2月的实测数据的分析,展示了Si∶N比值起因和Si生物地球化学过程,并且建立初级生产力与Si∶N的比值的动态方程。利用非保守性物质Si∶N比值作为湾内水的示踪剂,根据海湾的水交换完成的定义及海湾的充满和放空原理,应用作者提出的生物地球化学模型,计算得到胶州湾水交换时间的集合X={x︱10<x<15},其平均值为12.5 d。作者首次提出了新的海湾水交换时间(marine bay water exchange time)定义,包括从两个方面:海湾的充满和海湾的放空,来说明此定义。作者首次探讨了非保守性物质情况下,来确定海湾水交换时间的范围。作者首次给出了海湾水交换完成的定义,并且首次提出了海湾充满和放空的原理,然后利用了保守性物质或者非保守性物质作为湾内水的示踪剂,采用生物地球化学模型,计算得到海湾水交换时间的范围。作者的海湾水交换研究不需要以潮流动力学为背景,也不受到潮流模型的参数和变量影响。展开更多
A new method was developed for effective enrichment of Cd2+ ions from water with a calcium alginate(CaAlg) hydrogel filtration membrane. First, the CaAlg hydrogel filtration membrane was prepared without a pore-formin...A new method was developed for effective enrichment of Cd2+ ions from water with a calcium alginate(CaAlg) hydrogel filtration membrane. First, the CaAlg hydrogel filtration membrane was prepared without a pore-forming agent. This membrane was used to remove Cd^(2+) via ion exchange with Ca^(2+), and the Cd^(2+) was preserved in the CaAlg hydrogel. Then, the CaAlg hydrogel containing Cd^(2+) was soaked in a sodium citrate solution, and the hydrogel was fully dissolved. The removal rate of the CaAlg filtration membrane reached almost 100% within 120 min when the Cd^(2+) concentration was under 1 mg/L. Factors affecting the removal rate were investigated, such as NaAlg concentration, operating pressure, operating time and the initial concentration of Cd^(2+). The effects of initial Cd^(2+) concentration, pressure and filtration time on the enrichment factor were also investigated. The results show that the enrichment factor reached 87.3 when the pressure was 0.18 MPa and the filtration time was 240 min. Different enrichment factors could be achieved by adjusting the operating pressure and filtration time.展开更多
文摘通过胶州湾1991年5月至1994年2月的实测数据的分析,展示了Si∶N比值起因和Si生物地球化学过程,并且建立初级生产力与Si∶N的比值的动态方程。利用非保守性物质Si∶N比值作为湾内水的示踪剂,根据海湾的水交换完成的定义及海湾的充满和放空原理,应用作者提出的生物地球化学模型,计算得到胶州湾水交换时间的集合X={x︱10<x<15},其平均值为12.5 d。作者首次提出了新的海湾水交换时间(marine bay water exchange time)定义,包括从两个方面:海湾的充满和海湾的放空,来说明此定义。作者首次探讨了非保守性物质情况下,来确定海湾水交换时间的范围。作者首次给出了海湾水交换完成的定义,并且首次提出了海湾充满和放空的原理,然后利用了保守性物质或者非保守性物质作为湾内水的示踪剂,采用生物地球化学模型,计算得到海湾水交换时间的范围。作者的海湾水交换研究不需要以潮流动力学为背景,也不受到潮流模型的参数和变量影响。
基金supported by the National Natural Science Foundation of China(Grant Nos.51678409,21504063&51708407)the Special Scientific Research Fund of Agricultural Public Welfare Profession of China(Grant No.21403014-1)+1 种基金the Tianjin Science Technology Research Funds of China(Grant Nos.16JCZDJC37500,15JCQNJC08900&17JCQNJC08700)the Tianjin Science and Technology Correspondent Project(Grant No.16JCTPJC44800)
文摘A new method was developed for effective enrichment of Cd2+ ions from water with a calcium alginate(CaAlg) hydrogel filtration membrane. First, the CaAlg hydrogel filtration membrane was prepared without a pore-forming agent. This membrane was used to remove Cd^(2+) via ion exchange with Ca^(2+), and the Cd^(2+) was preserved in the CaAlg hydrogel. Then, the CaAlg hydrogel containing Cd^(2+) was soaked in a sodium citrate solution, and the hydrogel was fully dissolved. The removal rate of the CaAlg filtration membrane reached almost 100% within 120 min when the Cd^(2+) concentration was under 1 mg/L. Factors affecting the removal rate were investigated, such as NaAlg concentration, operating pressure, operating time and the initial concentration of Cd^(2+). The effects of initial Cd^(2+) concentration, pressure and filtration time on the enrichment factor were also investigated. The results show that the enrichment factor reached 87.3 when the pressure was 0.18 MPa and the filtration time was 240 min. Different enrichment factors could be achieved by adjusting the operating pressure and filtration time.
