Ecological Planting Imperative: Functional Systems,Not Stylized Ecologies

The ability of landscape architectural projects to mitigate the worst effects of climate change will depend upon designed ecological systems. These systems will be built with plants. Despite the recognition of ecology as an essential driver of landscapes, the professionals of landscape architecture too often lack the knowledge and practical skills to create robust vegetative systems. New approaches and tools are required. This article outlines principles and methods for designing biodiverse plant systems for urban sites. Planting methods that increase species richness, functional diversity, and spatial complexity are emphasized as a way of developing more resilient plantings. Selecting species with similar evolutionary adaptions to stress, disturbance, and competition—as well as creating multi-layered compositions of diverse plant morphologies—allows designers to create compatible, long-lived plant mixes. To balance the increased visual complexity of diverse plant mixes, the article explores design techniques to make plantings more appealing to the public. The strategies explored here are based on the projects, experience, and research of Phyto Studio, a Washington, D.C. based studio. The methods build on work described in the author’s book, Planting in a Post-Wild World, an exploration of how to create designed plant communities.     

A cross-linked sheet structured poly(3,4-ethylenedioxythiophene) grown on Ni foam: Morphology control and application for long-life cyclic asymmetric supercapacitor

In this work, a cross-linked sheet structured conducting polymer ploy(3,4-ethylenedioxythiophene) (PEDOT) decorated on Ni foam is synthesized via one-step electrodeposition using the sodium p-toluenesulfonate (STSA) as surfactant and applied for supercapacitor electrode. The surfactants play a vital role in controlling the morphologies of PEDOT leading to the electrochemical performance difference. The optimized PEDOT electrode exhibits the highest capacitance of 711.6 mF cm⁻² at 3.0 mA cm⁻² in the three-electrode system. An asymmetric device (PEDOT/STSA//AC) is constructed by PEDOT/STSA (the positive electrode), activated carbon (AC) (the negative electrode) as well as 1 M Na₂SO₄ (the electrolyte). The device has been worked in a high-voltage range of 0–1.5 V, which displays the satisfied energy density of 14.0 Wh·kg⁻¹ at 535.5 W kg⁻¹. Furthermore, the PEDOT/STSA//AC device presents excellent rate capability and long-time cyclic stability.     

Modified Two-Phase Titration Methods to Quantify Surfactant Concentrations in Chemical-Enhanced Oil Recovery Applications

In enhanced oil recovery applications, surfactants are injected into reservoirs along with polymers and salts. The effluents eluted from lab experiments and field tests are analyzed by HPLC methods using an evaporative light scattering detector (ELSD) detector. When the surfactant concentrations are less than 100 ppm, HPLC methods are inaccurate. A novel two-phase titration method is developed where surfactant concentrations can be quantified using a calibration curve constructed with UV/vis absorption. This method can analyze surfactant concentrations 5–80 ppm where dilution eliminates any high-salinity interferences with the absorption measurements. The method is based on formation of a dye-surfactant complex and the light absorption of the complex has a linear correlation with the surfactant concentration. Anionic surfactant concentrations lower than 100 ppm can be accurately quantified using this method with methylene blue. The method was also developed for low concentrations (<50 ppm) of cationic surfactants using methyl orange and indigo carmine. The indigo carmine method can be used without the use of an organic phase. All methods are applicable at salinities up to 3 wt%. Both the methylene blue method and the methyl orange method can be used to detect zwitterionic surfactants. These methods can be used in the presence of polymers without any prior treatments.     

Study on the Adaptability of Alkanolamide (LDEA) Lowering Oil/Water Interfacial Tension to Different Crude Oils

In order to investigate the high interfacial activity and fair oil phase adaptability of alkanolamide, “1:1” type lauric acid diethanolamide impurities (LDEA) were synthesized and purified by the column chromatography method to obtain dodecanoic acid diethanolamide (C₁₂DEA), ester mixture, etc. The exact structures of these compounds were further confirmed by IR, gas chromatogrph with mass spectroscopy (GC–MS), and NMR. The influence of each component on the interfacial tension of oil/water (IFT) was studied by systematic quantitative analysis. The results showed that (i) the strength of each system to reduce oil/water IFT is C₁₂DEA /DEA ≈ LDEA > C₁₂DEA/DEA/ESTER > C₁₂DEA/NaOH > C₁₂DEA > C₁₂DEA/ESTER > DEA. This indicates that LDEA contributes to the reduction of the oil/water IFT and the enhanced adaptability of crude oil in this order: DEA > > ESTER; (ii) when the IFT of the LDEA/DEA system reached an ultralow value, the minimum content of DEA in the system was 1%, and the maximum ester content was less than 5% when the LDEA/DEA/ESTER system reached the ultralow IFT; (iii) the possible mechanism of effect of LDEA components on the IFT and oil phase adaptability was proposed as the synergistic process among the hydrogen bonding, alkali effect, and interface self-assembly of molecules in the interfacial layer. The contribution of these three factors were hydrogen bonding > alkali effect > interface self-assembly.     

Control of self-assembly in micro- and nano-scale systems

Control of self-assembling systems at the micro- and nano-scale provides new opportunities for the engineering of novel materials in a bottom-up fashion. These systems have several challenges associated with control including high-dimensional and stochastic nonlinear dynamics, limited sensors for real-time measurements, limited actuation for control, and kinetic trapping of the system in undesirable configurations. Three main strategies for addressing these challenges are described, which include particle design (active self-assembly), open-loop control, and closed-loop (feedback) control. The strategies are illustrated using a variety of examples such as the design of patchy and Janus particles, the toggling of magnetic fields to induce the crystallization of paramagnetic colloids, and high-throughput crystallization of organic compounds in nanoliter droplets. An outlook of the future research directions and the necessary technological advancements for control of micro- and nano-scale self-assembly is provided.     

Synthesis conditions effect on the of photocatalytic properties of MnWO4 for hydrogen production by water splitting

This work aims to study the synthesis conditions effect on the photocatalytic properties of manganese tungstate (MnWO₄) for H₂ production by the water splitting reaction under visible light irradiation. This is achieved by relating the materials characterization and photocatalytic evaluation of MnWO₄ at different synthesis conditions. MnWO₄ was synthesized through a precipitation reaction between Mn²⁺ and (WO₄)^2- ionic species, while adding oleic acid (OA) as surfactant at two concentrations (0.1% and 1% V) and using three different stirring methods: magnetic stirring (AM), ultrasound (US) and high-shear stirring (UT). Characterization was carried out by TGA, XRD, BET surface area, UV–Vis spectroscopy and FESEM. XRD patterns confirm the wolframite structure of MnWO₄. BET surface area increased by using UT stirring. UV–Vis spectroscopy results revealed indirect transition Eg values of ≈2 eV, favorable for the MnWO₄ photoactivation under visible light irradiation. During the photocatalytic evaluation, sample 1%-UT produced the highest H₂ amount among all samples with a value of 72 μmolH₂g⁻¹, which was far higher compared to WO₃, which was taken as a reference photocatalyst.     

Utilizing sensor data to model students’ creativity in a digital environment

While creativity is essential for developing students’ broad expertise in Science, Technology, Engineering, and Math (STEM) fields, many students struggle with various aspects of being creative. Digital technologies have the unique opportunity to support the creative process by (1) recognizing elements of students’ creativity, such as when creativity is lacking (modeling step), and (2) providing tailored scaffolding based on that information (intervention step). However, to date little work exists on either of these aspects. Here, we focus on the modeling step. Specifically, we explore the utility of various sensing devices, including an eye tracker, a skin conductance bracelet, and an EEG sensor, for modeling creativity during an educational activity, namely geometry proof generation. We found reliable differences in sensor features characterizing low vs. high creativity students. We then applied machine learning to build classifiers that achieved good accuracy in distinguishing these two student groups, providing evidence that sensor features are valuable for modeling creativity.     

Investigation on concentration characteristics of ozone micro-bubbles fixed in ice and ozone gas released from ice

Ice formed from water in which ozone gas is dissolved is promising for the cold storage of foods because of the ozone's sterilization and deodorization capabilities. However, effective dissolution of ozone gas in water and taking ozone gas into ice are not easy. Furthermore, the decomposition rate of the ozone itself is usually very fast, regardless of its phase. Thus, to effectively take ozone gas into ice, the authors have developed ice containing ozone micro-bubbles. In this paper, ice containing ozone micro-bubbles formed by adding surfactant was kept for a desired time at a desired constant temperature without melting of the ice. The concentration of ozone micro-bubbles fixed in ice and the ozone gas concentration released from ice by melting were measured to investigate the ozone decomposition rate due to fixation in ice and the characteristics of the released concentration. Furthermore, the influences of surfactant on both concentrations were examined.     

Integrated smart grid systems security threat model

The smart grid (SG) integrates the power grid and the Information and Communication Technology (ICT) with the aim of achieving more reliable and safe power transmission and distribution to the customers. Integrating the power grid with the ICT exposes the SG to systems security threats and vulnerabilities that could be compromised by malicious users and attackers. This paper presents a SG systems threats analysis and integrated SG Systems Security Threat Model (SSTM). The reference architecture of the SG, with its components and communication interfaces used to exchange the energy-related information, is integrated with the results of SG systems security threat analysis to produce a comprehensive, integrated SG SSTM. The SG SSTM in this paper helps better depict and understand the vulnerabilities exploited by attackers to compromise the components and communication links of the SG. The SG SSTM provides a reference of the systems security threats for industrial security practitioners, and can be used for design and implementation of SG systems security controls and countermeasures.     

Formulation of a Biodegradable Detergent for Cleaning Oily Residues Generated during Industrial Processes

The use of toxic petroleum-based heavy oils is common in industrial processes. The cleaning of machines, equipment, and other surface covered in these oils is achieved with expensive products that are often also toxic and harmful to both the health of workers and the environment. The present paper proposes the development of a sustainable biodetergent made from plant-based materials. Tests were performed to determine the properties of the biodetergent in terms of its surfactant and emulsifying capacities, stability, toxicity, and the removal of heavy oil from glass plates and metallic surfaces. The formulation was composed of a natural solvent (cottonseed oil), a plant-based surfactant agent (saponin), and two natural stabilizers (carboxymethylcellulose and glycerine). The formulation was stable, nontoxic, and highly efficient, removing 100% of the heavy oil from glass and metallic surfaces. This solution developed in this study could be used in diverse industries with the need to clean machines and parts encrusted with oil and grease as well as the cleaning of floors covered with petroleum-based residues. A preliminary analysis of the economic feasibility of using the detergent was carried out at a Brazilian power plant. Besides the reduction in environmental impact due to the use of a nontoxic, biodegradable product as well as the reduction in health risks to workers associated with toxic cleaning products, this new product can have a considerable impact on the market as an environmentally friendly solution.