Water Management Applications for Satellite Precipitation Products: Synthesis and Recommendations

This article is an assessment of the current state of the art and relative utility of satellite precipitation products (SPPs) for hydrologic applications to support water management decisions. We present a review of SPPs, their accuracy in diverse settings including the influence of geography, topography, and weather systems, as well as the pros and cons of their use for different water management applications. At the end of this broad synthesizing effort, recommendations are proposed for: (1) SPP developers to improve the quality, usability, and relevance of precipitation products; and (2) SPP users to improve the reliability of their predictions and hydrologic applications to better support water management.     

复杂电磁环境仿真软件中的大地形文件传输技术研究

为了提高仿真速度,仿真软件一般采用多台计算机进行协同工作,首先搭建一套电波传播仿真并行系统,该系统能够导入地理信息,并在导入的地图上进行电磁辐射源建模及电磁环境仿真工作。但是,对于一些很大的地形,其海量的三维地形数据的传输时间过长,这加大了总的仿真等待时间。所以为了综合利用多台计算机的资源优势,提出使用BitTorrent方式,使得服务端与客户端的计算机均可以为地形文件的传输做贡献,极大减少了地形文件传输时间,可以从侧面提高仿真工作的效率。     

一种应用于双单元MIMO天线的电磁带隙结构设计与仿真

设计了一种应用于工作频率为2.6GHz的双单元多输入多输出（MIMO）天线的新型电磁带隙结构（EBG）。本文基于传统的蘑菇状结构,将贴片改进为螺旋状,调整偏移了过孔圆柱位置,并采用了电磁带隙结构单元的整体倒“T”形状布局。过孔的位置以及结构单元的间隔基于HFSS电磁仿真软件进行了优化,使新的结构在对天线系统传输特性影响很低的情况下更好的减小两个天线单元之间的耦合干扰。     

Co-metabolic transformation of the neonicotinoid insecticide imidacloprid by the new soil isolate Pseudoxanthomonas indica CGMCC 6648

A new imidacloprid (IMI) degrading bacterium Z-9 (deposited number CGMCC 6648) was isolated and identified as Pseudoxanthomonas indica by 16S rRNA gene analysis. Two metabolites were identified as olefin and 5-hydroxy IMI by liquid chromatography-mass spectrometry and nuclear magnetic resonance analysis. P. indica CGMCC 6648 degraded 70.1% of IMI (1.22 mmol L^?1) and formed 0.93 mmol L^?1 5-hydroxy IMI and 0.05 mmol L^?1 olefin IMI in 6 days and in the presence of 100 mmol L^?1 glucose. The half-life of IMI degradation was 3.6 days. P. indica CGMCC 6648 transforms IMI via a co-metabolism mechanism and different carbohydrates have significant effects on 5-hydroxy IMI formation, whereas different organic acids have substantial effects on olefin IMI production. Lactose is the best co-substrate for IMI degradation and 5-hydroxy IMI formation with 0.77 mmol L^?1 degraded and 0.67 mmol L^?1 formed in 48 h, respectively. Pyruvate is the best co-substrate for olefin IMI formation with 0.17 mmol L^?1 produced in 96 h for all carbon sources tested. Pyruvate significantly stimulates the conversion of 5-hydroxy IMI to olefin IMI, whereas glucose slightly inhibits this reaction. P. indica CGMCC 6648 rapidly degrades IMI and forms olefin IMI, which may enhance its potential for biodegradation of IMI and increase its insecticidal activity, which can decrease the IMI dosage required.     

瑞典环境税——政策效果及其对中国的启示

文章回顾了瑞典的环境税费，特别是与能源相关的环境税的发展沿革，从环境效益、财政效益、能源结构调整效应三个方面分析了瑞典能源一环境税的效果，并展望瑞典环境税的发展前景。最后指出了瑞典环境税制度对中国的借鉴意义。     

餐厨垃圾综合资源化处理技术实例研究

在目前餐厨垃圾处理现状基础上,介绍了一种餐厨垃圾处理工艺,采用机械生物处理技术,包括收运系统、粉碎分选预处理、厌氧发酵生物处理、沼气热电联供、有机堆肥、废水处理、除臭系统多个环节,分离出油脂进行回收,垃圾厌氧发酵产生沼气发电,沼渣进行堆肥,以期实现餐厨垃圾减量化、无害化、资源化,解决"垃圾猪"、"地沟油"问题。     

Heavy metal phytoextraction by Sedum alfredii is affected by continual clipping and phosphorus fertilization amendment

Improving the efficacy of phytoextraction is critical for its successful application in metal contaminated soils. Mineral nutrition affects plant growth and metal absorption and subsequently the accumulation of heavy metal through hyper-accumulator plants. This study assessed the effects of di-hydrogen phosphates (KH₂PO₄, Ca(H₂PO₄)₂, NaH₂PO₄ and NH₄H₂PO₄) application at three levels (22, 88 and 352 mg P/kg soil) on Sedum alfredii growth and metal uptake by three consecutive harvests on aged and Zn/Cd combined contaminated paddy soil. The addition of phosphates (P) significantly increased the amount of Zn taken up by S. alfredii due to increased shoot Zn concentration and dry matter yield (DMY) (P<0.05). The highest phytoextraction of Zn and Cd was observed in KH₂PO₄ and NH₄H₂PO₄ treatment at 352 mg P/kg soil. The amount of Zn removed by phytoextraction increased in the order of 1st clipping<2nd clipping<3rd clipping, and for Cd extraction the order was 2nd clipping<1st clipping<3rd clipping. These results indicate that the application of P fertilizers coupled with multiple cuttings can enhance the removal of Zn and Cd from contaminated soils by S. alfredii, thus shortening the time needed for accomplishing remediation goals.     

太阳模拟器大功率短弧氙灯放电特性试验测试

目的增强太阳模拟器氙灯驱动运行的可靠性,给太阳模拟器研制提供技术保障,针对太阳模拟器大功率短弧氙灯放电特性进行试验研究。方法设计太阳模拟器的大功率短弧氙灯放电特性测试方法,然后通过理论计算和实际测试验证氙灯电源初始电流对短弧氙灯放电特性的影响,并采用增设优化电路的方法对其放电特性进行改善。结果在初始电流为70 A和120 A两种情况下,弧光放电电流到达谷值以后的电流稳定度分别为1.8616和0.9867,增设优化电路后,再次进行短弧氙灯放电特性测量,将初始电流降低到60 A,而稳定度可达到0.5409。结论改善后的电路基本可实现短弧氙灯放电理想状态,完成了对短弧氙灯进入电流击穿阶段后形成的稳定弧光放电电流特性的优化,大大提升了氙灯点灯成功率,为增强太阳模拟器可靠性提供了试验支持。     

海泡石负载型纳米零价铁对水中Cu(Ⅱ)、Zn(Ⅱ)的去除研究

针对日益突出的水体重金属污染问题,采用液相还原法制备海泡石负载纳米零价铁(S-nZVI),并研究其对Cu(II)、Zn(II)的去除效果.同时,利用比表面积与孔径分析(BET)、透射电子显微镜(TEM)、X射线衍射(XRD)对制备出的材料进行表征,研究pH、S-nZVI投加量、重金属离子溶液初始浓度对去除率的影响,拟合S-nZVI材料去除Cu(II)、Zn(II)的动力学模型和吸附等温模型,并对反应后的S-nZVI进行回收及再生.结果表明,液相还原法可以成功制备出S-nZVI,且颗粒分布均匀.在60 min左右,S-nZVI对Cu(II)、Zn(II)的去除达到平衡.Cu(II)、Zn(II)的去除率随着pH值的升高而升高.当Cu(II)、Zn(II)溶液初始浓度为20 mg·L~(-1)时,最佳S-nZVI投加量分别为0.030、0.050 g,此时去除率分别为98.98%、98.97%.当Cu(II)浓度为90 mg·L~(-1)时,S-nZVI材料对Cu(II)的去除量最大,为127.57 mg·g~(-1);对Zn(II)来说,当浓度为110 mg·L~(-1)时去除量最大,为109.13 mg·g~(-1).去除过程符合准二级动力学模型和Langmuir吸附等温模型.S-nZVI可通过外加磁场进行回收,5次再生处理后其对Cu(II)、Zn(II)的去除率仍维持在96.84%、80.25%.实验结果显示,S-nZVI在废水除Cu(II)、Zn(II)领域具有很好的应用前景.