Feasibility Evaluation of Using Biochar-based Permeable Reactive Barrier for the Remediation of Mercury and Arsenic Composite Polluted Water Bodies

This study employed a modified biochar material to construct a permeable reactive barrier(PRB)for the treatment of water bodies polluted with mercury and arsenic.The experimental results demonstrated that the addition of goethite-modified biochar significantly enhanced the remediation efficiency of As(III),achieving a maximum removal rate of 100%.Conversely,pure biochar exhibited high efficiency in the removal of Hg(II),with a maximum removal rate approaching 100%.Furthermore,the pH level of the water significantly influenced the adsorption efficiency of heavy metal ions,with the optimal removal performance observed at a pH of 6.0.The PRB system demonstrated excellent removal rates under low concentrations of heavy metals.However,as the concentration increased,the remediation efficiency exhibited a slight decrease.In summary,the findings of this study provide compelling evidence for the use of modified biochar in the construction of PRBs for the remediation of mercury and arsenic-polluted water bodies.Furthermore,the study reveals the mechanism by which pH and heavy metal concentration influence remediation efficiency.

Preparation of Biomanganese Oxide-biochar Composite and Its Remediation of Arsenic Contamination

[Objectives]To prepare biomanganese oxide/biochar composite(BMO-BC)and examine its remediation performance on arsenic contamination.[Methods]The BMO-BC was prepared by cultivating Pseudomonas putida MnB1 in the presence of Mn 2+and biochar.[Results]The initial concentration of Mn 2+in the culture system had no significant effect on the growth rate and domestication cycle of Pseudomonas putida MnB1.The results of SEM-EDS and XRD analysis confirm that the adsorbent prepared in this experiment was a composite of biomanganese oxide and biochar particles.The results of arsenic pollution removal test in simulated environment showed that the in-situ formed BMO-BC composite had certain removal effect on As(III)and the presence of biochar particles and manganese dioxide in the reaction system and the manganese oxidation ability of microbial strain MnB1 affect its remediation performance to As(III).[Conclusions]When the initial concentration is in the range of 0-10.0 mg/L,the isothermal adsorption data of BMO-BC on As(III)conforms to the Langmuir model.

Characteristics of soil seed banks at different geomorphic positions within the longitudinal sand dunes of the Gurbantunggut Desert, China

Understanding the characteristics of soil seed banks in sand dunes is crucial to stabilize the dune systems and maintain the plant populations in deserts. In this study, we conducted a survey investigation in the field and a seed germination experiment in the laboratory to explore the characteristics of soil seed banks at various geomorphic positions of longitudinal sand dunes in the Gurbantunggut Desert, China. Totally, 17 plant species belonging to 17 genera and 9 families were identified in soil seed banks, and 35 plant species belonging to 34 genera and 17 families were identified in aboveground vegetation. Plant species richness in soil seed banks decreased with increasing soil depth. The highest species richness was presented in the upper slope of the windward slope and the lowest species richness was presented in the base of the windward slope. There was no significant difference in seed density of soil seed banks among the examined seven geomorphic positions. The highest seed density occurred in the lower slope of the leeward slope while the lowest occurred in the crest. Moreover, seed density decreased with increasing soil depth, being the highest in the upper soil layer （0-2 cm）. For both soil seed banks and aboveground vegetation, there was no significant difference in Simpson＇s diversity index among the seven geomorphic positions; however, Shannon-Wiener diversity index and Pielou＇s evenness index showed significant differences among the seven geomorphic positions. Those results showed that although there was no significant difference in seed density of soil seed banks among the seven geomorphic positions, the geomorphic positions significantly affected the species richness, diversity and distribution of soil seed banks. Therefore, understanding the characteristics of soil seed banks at different geomorphic positions of sand dunes is essential to vegetation restoration or reestablishment. Furthermore, the Jaccard＇s similarity coefficients of plant species between soil seed banks and aboveground vegetation at the seven geomorphic positions were low, suggesting that vegetation restoration or reestablishment processes should be promoted through adding seeds to surface layers.

树的线图的P_3-因子(英文)

In this paper,we give a necessary and sufficient condition for the existence of P3-factors in the line graph of a tree.Then we present an algorithm to determine whether the line graph of a tree has a P3-factor.

Research and Implementation for License Plate Recognition Based on Improved Projection Algorithm

This paper analyzes and dissertates the discrete wavelet transform and improved projection algorithm in four kernel stages （image preprocessing, license plate localization, character segmentation, license plate recognition, i.e.） of license plate recognition system in detail. At last, it gives some conclusions and suggestions on future research.

Analysis of Factors Influencing Residents'Satisfaction with Pairing Aid Policy in Xinjiang:Based on the Data from Three Prefectures in Southern Xinjiang

This article concentrates on evaluating residents'satisfaction with the implementation of the pairing aid policy in Xinjiang Uygur Autonomous Region.It introduces the key factors influencing the evaluation of residents'satisfaction with the performance of the pairing aid policy in Xinjiang by investigating the related data acquired from 12 field studies.It builds a binary logistic regression model via modern econometrics theory and utilizes the regression model to conduct the empirical analysis of influencing factors.The results reveal that there is no variation between the residents'education level,ethnicity,location,and satisfaction with the work of village cadres on the residents'evaluation of the implementation effect of the pairing aid policy in Xinjiang.Besides,ten variables such as residents'gender,age,revenue,occupation,whether they are rural residents,and satisfaction level(pairing aid policy in Xinjiang,state subsidy policy,medical improvement,education improvement,housing condition improvement)are steady and significant factors affecting residents'satisfaction with the implementation effect of pairing aid policy in Xinjiang.Finally,based on the analysis and findigns,it proposes corresponding countermeasures.

An RTI Model Support of Early Reading

Responsiveness to intervention(RTI)is a multi-tiered system of screening and early intervention for students at risk for academic failure.It provides high-quality instruction or intervention matched to student needs,monitoring progress frequently to make decisions about changes in instruction or goals,and applying child response data to important educational decisions(Stoiber,2014).The reauthorization the Individuals with Disabilities Education Improvement Act(IDEIA,2004)expressed subtle preference for RTI as method to identify students with Learning Disability(LD)(Healy,2005).More and more schools are exploring how to use the RTI model to address academic achievement needs of their students.