Application of hinokitiol potassium salt for wood preservative

The decay of wood and other cellulosic materials by fungi cause significant economic loss. The widely used chromated copper arsenate was prohibited for the environmental impact and safety of arsenic and chromium. It was found that natural product hinokitiol (HK) had fungicidal and insecticidal activities, and its toxicity was bearable for the environment. We described the practical synthesis of HK-K salt. According to the GB/T18261-2000 and LY/T1283-1998, wood preservative performance of HK-K salt was tested. The results showed that the best inhibitory concentration of HK-K salt was 50 mg/L, for which the prevention effectiveness on mold is better, the killed value is between 0 and 1, and the corrosion-resistant for wood-rotting fungi is grade A.     

A critical review on the application of biochar in environmental pollution remediation: Role of persistent free radicals (PFRs)

Biochar as an emerging carbonaceous material has exhibited a great potential in environmental application for its perfect adsorption ability. However, there are abundant persistent free radicals (PFRs) in biochar, so the direct and indirect PFRs-mediated removal of organic and inorganic contaminants by biochar was widely reported. In order to comprehend deeply the formation of PFRs in biochar and their interactions with contaminants, this paper reviews the formation mechanisms of PFRs in biochar and the PFRs-mediated environmental applications of biochar in recent years. Finally, future challenges in this field are also proposed. This review provides a more comprehensive understanding on the emerging applications of biochar from the viewpoint of the catalytic role of PFRs.     

低含液输气管道内积液特性研究现状及展望

管道的湿气输送过程是典型的低持液率气液两相流工况。从湿气输送过程积液形成的机理出发,分析了流体性质、输送条件、管道结构3类参数对积液形成的影响规律,结果表明管道倾角、管径、气液比是积液形成的主要影响因素。回顾了理论模型的发展历程并对比分析了不同模型的精确性,阐述了各稳态和瞬态模拟软件的适用范围和优缺点,介绍了超声波等无损检测技术在流型识别和积液高度检测领域的应用现状,进而分析了3种方法各自存在的不足,展望了未来的研究方向可以从多起伏大倾角粗管径室内实验工况、高精度可视化多相流模拟器以及高精度易操作非介入式检测技术开展,为集输管线的积液消除和管线长周期安全运行发挥关键支撑作用。     

Bioaccumulation and effects of sediment-associated gold- and graphene oxide nanoparticles on Tubifex tubifex

With the development of nanotechnology,gold(Au) and graphene oxide(GO) nanoparticles have been widely used in various fields,resulting in an increased release of these particles into the environment.The released nanoparticles may eventually accumulate in sediment,causing possible ecotoxicological effects to benthic invertebrates.However,the impact of Au-NPs and GO-NPs on the cosmopolitan oligochaete,Tubifex tubifex,in sediment exposure is not known.Mortality,behavioral impact(GO-NP and Au-NP) and uptake(only Au-NP) of sediment-associated Au-NPs(4.9±0.14 nm) and GO-NPs(116±0.05 nm) to T.tubifex were assessed in a number of 5-day exposure experiments.The results showed that the applied Au-NP concentrations(10 and 60 μg Au/g dry weight sediment) had no adverse effect on T.tubifex survival,while Au bioaccumulation increased with exposure concentration.In the case of GO-NPs,no mortality of T.tubifex was observed at a concentration range of 20 and180 μg GO/g dry weight sediment,whereas burrowing activity was significantly reduced at 20 and 180 μg GO/g dry weight sediment.Our results suggest that Au-NPs at 60 μg Au/g or GO-NPs at 20 and 180 μg GO/g were detected by T.tubifex as toxicants during short-term exposures.     

Predicting the economic costs and property value losses attributed to sudden oak death damage in California (2010-2020)

Phytophthora ramorum, cause of sudden oak death, is a quarantined, non-native, invasive forest pathogen resulting in substantial mortality in coastal live oak (Quercus agrifolia) and several other related tree species on the Pacific Coast of the United States. We estimate the discounted cost of oak treatment, removal, and replacement on developed land in California communities using simulations of P. ramorum spread and infection risk over the next decade (2010-2020). An estimated 734 thousand oak trees occur on developed land in communities in the analysis area. The simulations predict an expanding sudden oak death (SOD) infestation that will likely encompass most of northwestern California and warrant treatment, removal, and replacement of more than 10 thousand oak trees with discounted cost of $7.5 million. In addition, we estimate the discounted property losses to single family homes of $135 million. Expanding the land base to include developed land outside as well as inside communities doubles the estimates of the number of oak trees killed and the associated costs and losses. The predicted costs and property value losses are substantial, but many of the damages in urban areas (e.g. potential losses from increased fire and safety risks of the dead trees and the loss of ecosystem service values) are not included.     

普光气田环境空气植物监测体系的初步构想

在简要回顾国内外有关植物监测大气污染研究的基础上,针对普光气田主要大气污染因子与环境监测现状,从监测植物筛选、监测点位选取、监测体系标准化、"植物-大气-土壤"综合评价系统以及应急监测机制等五个方面,讨论了构建该地区环境空气植物监测体系的基本想法和建议,并进行了展望,供项目建设决策参考。     

Development of TRIPLEX-Management model for simulating the response of forest growth to pre-commercial thinning

In order to simulate forest growth response to pre-commercial thinning (PCT), TRIPLEX1.0 - a process-based model designed to predict forest growth as well as carbon (C) and nitrogen (N) dynamics - was modified and improved to also simulate managed forest ecosystem thinning practices. A three-parameter Weibull distribution model was integrated to simulate thinning treatments within the newly developed TRIPLEX-Management model. The thinning intensity component within the model allows users to simulate thinning treatments by applying basal area, stand density and volume to quantify thinning intensity. Natural mortality decreased following thinning due to an increase in growing space for residual stems. Predicted litterfall pools also increased after thinning events took place. The TRIPLEX-Management model was tested against published observational data for Jack Pine (Pinus banksiana Lamb.) stands subjected to PCT in Northwestern Ontario, Canada. The coefficients of determination (R²) between the predicted and observed variables including stand density, mean DBH (diameter at breast height), the quadratic mean DBH, total volume and merchantable volume as well as belowground, aboveground, and total biomass ranged from 0.50 to 0.88 (n = 20, P < 0.001) with the exception of mean tree height (R² = 0.25, n = 20, P < 0.05). Overall, the Willmott index of agreement between predicted and observed variables ranged from 0.97 to 1.00. Results show that the TRIPLEX-Management model is generally capable of simulating growth response to PCT for Jack Pine stands.     

重金属和油处理剂对水稻根系的影响

试验了Ｎｉ、Ｚｎ、Ｍｎ、Ｓｎ、Ｃｒ和Ｃｕ等６种重金属及油处理剂对水稻根系的影响，结果表明．水中含Ｎｉ０．００７ｍｇ／１、Ｃｕ０．００５ｍｇ／１时，能阻碍根系的伸长；含Ｚｎ０．５ｍｇ／１以上时。不利于根系的伸长；水中含Ｍｎ２０ｍｇ／１，Ｓｎ、Ｃｒ￣（６－）各５ｍｇ／１时，对根系有明显危害；水中含Ｃｒ￣（２＋）＋Ｃｒ￣（６＋）时，当１种离子浓度保持不变，根系的抑制程度随着另１种离子浓度的增加而增大。水中含油处理剂１０００ｍｇ／１时，能抑制水稻发根。     

提高地震台网近震速报精度的一个方法——和达法

本文对和达曲线法鉴别近震直达P波和直达S波的原理进行了详细的讨论,得出确定和达曲线参数的基本公式及用来表示S-P到时差与P到时线性相关程度的相关系数r的计算方法.讨论了利用和达曲线在台网定位中的应用方法.最后研制了利用和达曲线提高震相识别精度的应用程序,并以实例说明该程序的用法.     

Development of systems for detection, early warning, and control of pipeline leakage in drinking water distribution: A case study

The integrated system for the detection, early warning, and control of pipeline leakage has been successfully developed to manage the pipeline networks of Beijing.