Advances in remediation of heavy metal contaminated soil and water by Leersia hexandra Swartz
Heavy metal pollution is extremely harmful to human beings. Looking for an efficient and environmentally friendly treatment method is the focus of current research. Using plants to treat contaminated water and soil has proven to be an effective and environmentally friendly method. Leersia hexandra Swartz is a chromium hyperaccumulator, and it can also enrich copper and nickel. Since the super enrichment characteristics of Leersia hexandra Swartz were discovered, many scholars have poured into the research on Leersia hexandra Swartz. This article will give an overview of the current application status of Leersia hexandra Swartz’s purification of polluted water and soil, analyze the methods and principles used, and discuss the future development direction of Leersia hexandra Swartz’s plant remediation technology.
Upgrading Development and Application of Agricultural Information Service System Based on WeChat Public Platform— —A Case of WeChat Public Platform of 12396 Beijing new rural sci-tech service hotline
The WeChat public platform is a new service platform based on WeChat applications that provides business services and user management for individuals, businesses and organizations. It provides a new solution to the lag of agricultural information dissem-ination in the traditional media. However, services based on Tencent's backend can only meet the basic needs of users and reduce the user's experience in agricultural science and technology consulting process. In order to provide efficient and convenient service to users and solve existing problems in consultation process, the platform-related API were used to upgrade the 12396 hotline WeChat public platform to an integrated agricultural information interactive service system. It mainly carries out the following three aspects to upgrade development. Firstly, 12396 hotline WeChat public platform added two sub-menu items, “use ask” and “expert answer” to push the user’s question to expert directly, reducing the backend customer service’s works and improving the efficiency of problem solving. Secondly, 12396 WeChat public platform upgraded and developed an integrated "one-stop" micro-site to allow users know the agriculture market timely, releasing supply and demand information, etc. Thirdly, the 12396 WeChat public platform combined initiative push information with the user's automatic acquisition of information by sending keywords which increased user selectivity. The upgraded platform has obtained a good preliminary application achievement and recognized and welcomed by users. Finally, we concluded and looked forward to the future development direction of agricultural mobile consulting.
Mobile target defense (MTD) is a research hotspot in the field of network security. The decision method of network defense based on game theory is an important technique to guide MTD to make the optimal defense behavior in different network environments (GT-MTD). A lot of related work has been put forward in this field. In this paper, we focus on the scope and field of GT-MTD, systematically introduce the application scenarios of MTD in combination with four different game theory models of classical games (static games, signal games), Markov games, differential games or evolutionary games, and put forward the future development direction. There are some new views and explanations on the research of GT-MTD.
Abstract Wearable electronics are an essential direction for the future development of smart wearables. Among them, the battery life of wearable electronics is a key technology that limits their development. The proposal of self-powered wearable electronics (SWE) provides a promising solution to the problem of long-term stable working of wearable electronics. This review has made a comprehensive summary and analysis of recent advances on SWE from the perspectives of energy, materials, and ergonomics methods. At the same time, some representative research work was introduced in detail. SWE can be divided into energy type SWE and sensor type SWE according to their working types. Both types of SWE are broadly applied in human–machine interaction, motion information monitoring, diagnostics, and therapy systems. Finally, this article summarizes the existing bottlenecks of SWE, and predicts the future development direction of SWE.
Abstract Pollution of soil and water with heavy metals such as mercury, cadmium and arsenic, is a worldwide problem. Phytoremediation, the use of plants to remove, sequester or detoxify pollutants, including heavy metals, offers an environmentally-friendly alternative to engineering- based methods for remediation. Forest trees have multiple features that make them particularly useful for removal of toxic heavy metals, especially if they can be engineered with genes allowing them to handle high levels of these elements. Although still in its infancy, research with transgenic trees carrying genes allowing them to detoxify or sequester some heavy metals has already made promising progress. Most of the work to date has been performed using poplar species and hybrids, although other woody species could be equally as useful. Trees have been engineered with genes for the handling of mercury, cadmium, copper and arsenic following two main approaches, phytoextraction and phytotransformation/ phytovolatilizaton. In vitro studies have shown the transgenic trees to have enhanced abilities to tolerate and/or accumulate these metals, and preliminary results from field tests indicate that the trees are functioning. New combinations of genes involved in metal transport or conversion may further enhance the heavy metal remediation capabilities of the transgenic trees. Given the environmentally friendly application, forest trees engineered for phytoremediation may be some of the first transgenic forest trees approved for operational deployment.
Text similarity measurement is the basis of natural language processing tasks, which play an important role in information retrieval, automatic question answering, machine translation, dialogue systems, and document matching. This paper systematically combs the research status of similarity measurement, analyzes the advantages and disadvantages of current methods, develops a more comprehensive classification description system of text similarity measurement algorithms, and summarizes the future development direction. With the aim of providing reference for related research and application, the text similarity measurement method is described by two aspects: text distance and text representation. The text distance can be divided into length distance, distribution distance, and semantic distance; text representation is divided into string-based, corpus-based, single-semantic text, multi-semantic text, and graph-structure-based representation. Finally, the development of text similarity is also summarized in the discussion section.
Heavy metals contaminated sediment has become a worldwide environmental issue due to its great harm to human and aquatic organisms. Thus, economical, effective, and environmentally-friendly remediation technologies are urgently needed. Among which, combined remediation technologies have attracted widespread attention for their unique advantages. This paper introduces combined remediation technologies based on physical-, chemical-, and bio-remediation of heavy metal polluted sediments. Firstly, the research progress in physical-chemical, bio-chemical, and inter-organismal (including plants, animals, microorganisms) remediation of heavy metal polluted sediments are summarized. Additionally, the paper analyzes the problems of the process of combined remediation of heavy metals in river sediments and outlooks the future development trends of remediation technologies. Overall, this review provides useful technology references for the control and treatment of heavy metal pollution in river sediments.
Explorations of Charm Factors and Development of Fishing in Southern Taiwan Based on Miryoku Engineering and the Analytic Network Process
Fishing is a popular leisure activity all over the world. However, due to the differences in local customs and cultures, fishing shows regional differences. This study aims to explore the charm of fishing in Southern Taiwan. In this study, the Miryoku engineering method was used to analyze and determine the charm characteristics of fishing in Southern Taiwan and draw the EGM evaluation structure chart. Thereafter, with the analytic network process method, the evaluation model was established in order to calculate the weight and ranking of each charm item. Then the weights of the 35 items in the summit, middle and bottom levels were obtained. The analysis results showed that fishing in Southern Taiwan was similar to that in other parts of the world, but the charm factors of fishing in Southern Taiwan had its relaxation and leisure characteristics. According to the analysis results of the charm factors of fishing, we discussed the future development direction of fishing industry based on the charm characteristics of fishing in Southern Taiwan.
Perylene tetracarboxylic diimide (PDI) and its derivatives exhibit excellent thermal, chemical and optical stability, strong electron affinity, strong visible-light absorption and unique fluorescence on/off features. The combination of these features makes PDIs ideal molecular frameworks for development in a broad range of sensors for detecting environmental pollutants such as heavy metal ions (e.g., Cu2+, Cd2+, Hg2+, Pd2+, etc.), inorganic anions (e.g., F−, ClO4−, PO4−, etc.), as well as poisonous organic compounds such as nitriles, amines, nitroaromatics, benzene homologues, etc. In this review, we provide a comprehensive overview of the recent advance in research and development of PDI-based fluorescent sensors, as well as related colorimetric and multi-mode sensor systems, for environmental detection in aqueous, organic or mixed solutions. The molecular design of PDIs and structural optimization of the sensor system (regarding both sensitivity and selectivity) in response to varying analytes are discussed in detail. At the end, a perspective summary is provided covering both the key challenges and potential solutions for the future development of PDI-based optical sensors.
Nanocopper has become one of the research hotspots of metal powder for 3D printing, due to its excellent properties. In this paper, technical methods, process flow and research progress were systematically introduced of nanocopper powder for 3D printing. Preparation of nano-copper powder for 3D printing are mainly physical and chemical methods. Physical methods include atomization method, physical vapor deposition method, grinding method, electric explosion method. Chemical methods include sol-gel method, radiation chemistry, plasma, microemulsion, hydrothermal, liquid reduction and so on. The advantages and disadvantages of these methods were compared in detail, and the future development direction of nano-copper powder for 3D printing was look forward to.
This article first introduced the survey of mechanical fault diagnosis technology development and the data mining technology theory. Then its application situation at present and the main questions that exist are elaborated. Its development trend is analyzed. The application feasibility of using data mining technology in mechanical fault diagnosis is discussed. Next, the naissance, the development and the future development tendency of data mining technology are introduced. The four algorithms are analyzed and the framework is built too. Intelligent Diagnosis is a major development direction of the fault diagnosis. Knowledge acquisition is the bottleneck of Intelligent Diagnosis development. It comprehensive use of many kinds of advanced technology, discover valuable and hidden knowledge from the large amounts of data mining.