Charged Sites Research Articles

Abstract 3752: Identification of nanobodies specific for the oncogenic protein tyrosine phosphatase 4A3 (PTP4A3/PRL-3) that modulate its binding, stability, and phosphatase activity

Abstract PRL-3 is an oncogenic phosphatase across multiple cancer types, including colon, ovarian, melanoma, breast, and leukemia. While there is increasing interest in developing PRL-3 inhibitors for use in cancer research and treatment, there have been several issues in designing small molecule inhibitors for PRL-3, such as a shallow, negative charged active site, homology between the PRL-3 active site and other protein tyrosine phosphatases, and a high degree of overall homology between PRL-3 and family members PRL-1 and PRL-2. Nanobodies have recently emerged as an immensely useful research tool and show promise as a cancer therapeutic. Nanobodies are small, at ~15kD and lack light chains, allowing them to fit into spaces on target proteins that conventional antibodies cannot normally reach. Other advantages of nanobodies include their stability under stringent conditions, lack of immunogenicity, ability to permeate the cell, and a high specificity and affinity for their antigens. Using full-length PRL-3 protein as an immunogen in alpaca, I used phage display technology to identify alpaca nanobodies that had high affinity for PRL-3 through subtractive panning. I identified 18 unique nanobodies through sequencing; 14 of these were able to be expressed in bacteria and purified. The binding specificity of the nanobodies to PRL-3 over PRL-1 and PRL-2 was determined through an indirect ELISA assay, which showed that that 12 out of 14 anti-PRL-3 nanobodies bound PRL-3 significantly better than PRL-1 or PRL-2 (~25X times higher binding affinity to PRL-3, p<0.0001). I also identified several nanobodies that stabilize PRL-3 structure using a Differential Scanning Fluorescence (DSF) assays to analyze shifts in the melting temperature of PRL-3 following binding, with the ultimate goal of developing PRL-3/nanobody crystal structures to identify nanobody binding sites and find PRL-3 active site binders. Additionally, I have found the 6X-Histidine-tagged nanobodies are useful for PRL-3 western blot, immunoprecipitation, and immunofluorescence, and mCherry-tagged nanobodies (chromobodies) allow for analysis of PRL-3 trafficking. Nanobodies were also tested for their ability to inhibit the phosphatase activity of PRL-3, using both purified protein and functional in vitro assays. Preliminary results showed that several nanobodies decreased PRL-3 phosphatase activity, and cell-based assays to assess how nanobody expression affects PRL-3 function and cellular phenotype are ongoing. Overall, we have developed. both a novel research tool that can be used to gain insight into the structure and function of PRL-3 in normal and cancer cells, and a potentially new biologic inhibitor of PRL-3 that functions with high specificity and potency. Citation Format: Caroline N. Smith, K. Martin Chow, Louis B. Hersh, Jessica S. Blackburn. Identification of nanobodies specific for the oncogenic protein tyrosine phosphatase 4A3 (PTP4A3/PRL-3) that modulate its binding, stability, and phosphatase activity [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 3752.

Insight into the key factors in fast adsorption of organic pollutants by hierarchical porous biochar

Low-cost biochar adsorbent owning great potential for environmental remediation faces a bottleneck in application for its unsatisfied adsorption performance. Compared to the efforts on increasing adsorption capacity, improving adsorption speed which is important for treatment efficiency is often neglected. Herein, a hierarchical porous biochar (HPB) derived from shrimp shell was prepared and exhibited good adsorption capacity (Qm>300 mg/g) and fast adsorptive equilibrium (≤10 min) towards three typical aromatic organics, whose adsorption universality was further proved by two-way ANOVA analysis. Whereafter, model analysis demonstrated that, the adsorptive forms (mono- and multi-layers) on HPB depended on whether the contaminant is charged. Compared to the benzene-ring site of organics, the charged site contributed 5.13 times to adsorption promotion in monolayer but -0.49 times in inhibition for multilayers forms. Simultaneously, functional group sites contributed relatively weak (0.023 to 0.342 times only). Following structural control revealed that, hierarchical pore structure of HPB was the key for the fast adsorption speed, and highly graphitic structure was important for the high adsorption capacity. This study aims to provide an advanced biochar adsorbent, not only in adsorption capacity but also in adsorptive speed, and reveal the relationship between the structure and adsorption performance of biochar.

FT-IR and FT-Raman investigation, quantum chemical analysis and molecular docking studies of 5-(4-Propan-2-yl)benzylidene)-2-[3-(4-chlorophenyl)-5[4-(propan-2-yl)phenyl-4,5-dihydro-1H-pyrazol-1-yl]-1,3-thiazol-4(5H)-one

The FT-IR and FT-Raman spectra of 5-(4-Propan-2-yl)benzylidene)-2-[3-(4-chlorophenyl)-5[4-(propan-2-yl)phenyl-4,5-dihydro-1H-pyrazol-1-yl]-1,3-thiazol-4(5H)-one were recorded and analyzed. The fundamental vibrational wavenumbers, intensities of vibrational bands and the optimized geometrical parameters of the compound were evaluated using DFT (B3LYP) method with 6–31 G, 6–31G(d,p) basis sets.Stability of the molecule arising from hyper conjugative interactions, charge delocalization has been analysed using natural bond orbital (NBO) analysis. Information about the size, shape, charge density distribution and site of chemical reactivity of the molecule has been obtained by mapping electron density isosurface with molecular electrostatic potential (MEP) surface. The calculated HOMO-LUMO energies also show that the charge transfer occurs within the molecule. The global reactivity parameters which are obtained by frontier molecular orbital disclose that the molecule might be bioactive. To explain the chemical selectivity or the reactivity site in the molecule, the electron density-based local reactivity descriptors such as Fukui functions were calculated. The reduced density gradient of the title molecule was investigated by the interaction of the molecule. Molecular docking studies were also described. This study may also provide a further investigation of thiazole derivatives for pharmacological importance.

Structural Insight into Binding of the ZZ Domain of HERC2 to Histone H3 and SUMO1

Human ubiquitin ligase HERC2, a component of the DNA repair machinery, has been linked to neurological diseases and cancer. Here, we show that the ZZ domain of HERC2 (HERC2ZZ) binds to histone H3 tail and tolerates posttranslational modifications commonly present in H3. The crystal structure of the HERC2ZZ:H3 complex provides the molecular basis for this interaction and highlights a critical role of the negatively charged site of HERC2ZZ in capturing of A1 of H3. NMR, mutagenesis, and fluorescence data reveal that HERC2ZZ binds to H3 and the N-terminal tail of SUMO1, a previously reported ligand of HERC2ZZ, with comparable affinities. Like H3, the N-terminal tail of SUMO1 occupies the same negatively charged site of HERC2ZZ in the crystal structure of the complex, although in contrast to H3 it adopts an α-helical conformation. Our data suggest that HERC2ZZ may play a role in mediating the association of HERC2 with chromatin.

2H-1,2,3-Triazole-chalcones as novel cytotoxic agents against prostate cancer

Prostate cancer is an important cause of death in the male population and for which there is no satisfactory chemotherapy. Herein a new series of chalcone hybrids containing 2H-1,2,3-triazole core as the ring B has been synthesized and evaluated in vitro against PC-3 prostate cancer cell line. Compounds 4a, 4c and 4e significantly reduced cell viability and showed IC50 of 28.55, 15.64 and 25.56 µM, respectively. The structure-activity relationship supported by computational chemistry points that the polarity of the molecular surface area should have some relevance to the efficiency of the compounds, in particular the ratio of the partial positive charge sites and the total molecular surface area exposed to the cell environment.

Conditions and mechanisms of noble metals ions sorption in the process of their preconcentration on the new polyvinylpyridine sorbents

Natural sources of noble metals (Ru, Rh, Pd, Os, Ir, Pt, Au) are exhaustible, thus the extraction of metal from anthropogenic sources seems very promising. This work presents an investigation of new N-heterocyclic sorbents based on polyvinylpyridine for reversible extraction of noble metals from complex matrix solutions. This type of sorbents shows good resistance to aggressive acidic media and sufficient sorption capacity in both dynamic and static modes. It was found, to achieve quantitative sorption of Rh and Ir it is necessary to convert these analytes completely into their chloride form at the stage of sample preparation. Based on a series of experimental data, possible mechanisms of retention of noble metals’ chlorocomplexes on this type of sorbents are proposed. The UV–Vis spectra of various noble metals chlorocomplexes were studied in the presence of model compounds that simulate the repeating units of the sorbents. We assume that the chlorocomplexes of Rh, Ir, and possibly Ru form simple ion pairs with positively charged sorption sites. While Pd, Pt, and Au form more stable complexes (possibly intra-sphere) with sorbent units. The mechanism of Os sorption is unclear and requires a more detailed investigation. This information helps to select suitable desorption solutions for the extraction of analytes from the sorbent. The desorption solution should contain electrolytes, acid, and complexing reagents necessary for the quantitative recovery of noble metals due to the different sorption mechanisms and the various contribution of electrostatic forces to the efficiency of chlorocomplexes retention.

Predicting DNA binding protein-drug interactions based on network similarity

BackgroundThe study of DNA binding protein (DBP)-drug interactions can open a breakthrough for the treatment of genetic diseases and cancers. Currently, network-based methods are widely used for protein-drug interaction prediction, and many hidden relationships can be found through network analysis. We proposed a DCA (drug-cluster association) model for predicting DBP-drug interactions. The clusters are some similarities in the drug-binding site trimmers with their physicochemical properties. First, DBPs-drug binding sites are extracted from scPDB database. Second, each binding site is represented as a trimer which is obtained by sliding the window in the binding sites. Third, the trimers are clustered based on the physicochemical properties. Fourth, we build the network by generating the interaction matrix for representing the DCA network. Fifth, three link prediction methods are detected in the network. Finally, the common neighbor (CN) method is selected to predict drug-cluster associations in the DBP-drug network model.ResultThis network shows that drugs tend to bind to positively charged sites and the binding process is more likely to occur inside the DBPs. The results of the link prediction indicate that the CN method has better prediction performance than the PA and JA methods. The DBP-drug network prediction model is generated by using the CN method which predicted more accurately drug-trimer interactions and DBP-drug interactions. Such as, we found that Erythromycin (ERY) can establish an interaction relationship with HTH-type transcriptional repressor, which is fitted well with silico DBP-drug prediction.ConclusionThe drug and protein bindings are local events. The binding of the drug-DBPs binding site represents this local binding event, which helps to understand the mechanism of DBP-drug interactions.

1D and 2D basin modeling, in evaluating the hydrocarbon generation-migration-accumulation potential, at coastal Fars Area, Southern Iran

One of the giant hydrocarbon generation zones in Iran has been developed in the south of the Zagros Mountain Range (i.e., South Zagros), located between the South Zagros and the Persian Gulf in a foreland basin known for high levels of exploration uncertainties (due to the presence of complex structures, multiple source layers, and migration pathways). In this basin, the Permotriassic formations provide for the main reservoir strata, while the hydrocarbon content is deemed to be derived from the “hot shales” of the Silurian-Ordovician Sarchahan Formation, serving as source rock. As the focus of the present research, the Coastal Fars region is developed along the shores of southern Iran and hosts a number of gas reservoirs that have been increasingly discovered since 1970. Developed in the Permotriassic siliciclastics and carbonates of the Faraghan, Dalan, and Kangan Formations, gas reservoirs have made the Coastal Fars a hot zone for exploration and production activities. In this research, one 2D and five 1D models of the basin (at five exploration wells) were constructed to evaluate the maturity of the main Silurian-Ordovician source rock and further investigate the hydrocarbon charge, timing, migration pathways, and accumulation sites. The models were then utilized to investigate the relationship between the presence of multiple shale layers and hydrocarbon content of the reservoir at one of the studied wells using Rock-Eval analysis. This study showed that an uplift that happened after the hydrocarbon generation has led to a dry hole in the study area. The results indicated that the Sarchahan Formation is probably the main source rock across the region, according to previous researches in this area its organic contents were dated back to the late Ordovician rather than the Silurian. The shale intercalations across the reservoirs (Kangan and Upper Dalan), especially in the Khayam Field, were found to produce more than 90% of their hydrocarbon generation potential. No non-indigenous hydrocarbon was identified across the study area, implying that the entire hydrocarbon content was generated by the identified source rocks. Laboratory analysis indicated the presence of type II and type III kerogen at a local heat flow rate of about 65 mW/m2 since the Cretaceous. In total, the Sarchahan Formation was found to reach a maximum burial depth of 6 km, making it matured to overmatured all over the study area.

Probing Heterogeneous Charge Distributions at the α-Al2O3(0001)/H2O Interface.

Unlike metal or semiconductor electrodes, the surface charge resulting from the protonation or deprotonation of insulating mineral oxides is highly localized and heterogeneous in nature. In this work the Stark active C≡N stretch of potassium thiocyanate is used as a molecular probe of the heterogeneity of the interfacial electrostatic potential at the α-Al2O3(0001)/H2O interface. Vibrational sum frequency generation (vSFG) measurements performed in the OH stretching region suggest that thiocyanate species organize interfacial water similarly to halide ions. Changes in the electrostatic potential are then tracked via Stark shifts of the vibrational frequency of the thiocyanate stretch. Our vSFG measurements show that we can simultaneously measure the vSFG response of SCN- ions experiencing charged and neutral surface sites. We assign local potentials of +308 and -154 mV to positively and negatively charged aluminol groups that are present at pH = 4 and pH = 10, respectively. Thiocyanate anions at positively charged surface sites and negatively charged surface sites and those participating in contact ion pairing adopt similar orientations and are oppositely oriented relative to thiocyanate ions near neutral surface sites. All four species followed Langmuir adsorption isotherms. Density functional theory-molecular dynamics (DFT-MD) simulations of SCN- near the neutral α-Al2O3(0001)/H2O interface show that the vSFG response in the C≡N stretch region originates from a SCN-H-O-Al complex, suggesting the surface site specificity of these experiments. To our knowledge this is the first spectroscopic measurement of local potentials associated with a heterogeneously charged surface. The ability to probe the evolution of local charges in situ could provide vital insight into many industrial, electrochemical, and geochemically relevant interfaces.

Molecular modeling analyses for graphene functionalized with Fe3O4 and NiO

Graphene has attracted great concern in recent years as one of the potential 2D materials in various applications. This work is devoted for assessing the feasibility of functionalizing 2D graphene sheets with ferromagnetic and antiferromagnetic metal oxides namely magnetite (Fe3O4) and nickel oxide (NiO). Molecular models of the proposed candidates are exposed to energy calculations at DFT level, in addition to geometry optimization processes at PM6 method. HOMO/LUMO orbitals, MESP maps and QSAR descriptors are calculated. Results ensure that graphene doped with NiO has the highest reactivity since it possesses the largest TDM and the smallest HOMO/LUMO band gap. MESP maps illustrate that the benzene rings of graphene are most probable to undergo nucleophilic interactions. Addition of Fe3O4 creates new negatively charged active sites that are ready for nucleophilic interactions. The calculated QSAR parameters demonstrate a hydrophobic nature for pure and modified graphene suggesting that they need further modification with further groups for usage in biological applications.

Layered double hydroxides supported atomically precise Aun nanoclusters for air oxidation of benzyl alcohol: Effects of size and active site structure

The effects of size and active site structure on catalytic activity were deeply investigated in air oxidation of benzyl alcohol over a series of Ni3Al-LDH (layered double hydroxides)-supported Aun nanocluster (NC) catalysts Aun/LDH (n = 25, 38, ~127), obtained by modified electrostatic adsorption of atomically precise Au25Capt18, Au38Capt24 and Au~127-Capt (Capt: captopril) NCs followed proper calcination. Detailed characterizations show that the Au25/LDH, Au38/LDH and Au~127/LDH possess ultrafine Au NCs size of 1.2 ± 0.2, 1.4 ± 0.3 and 1.8 ± 0.5 nm, respectively, which are majorly dispersed on the edge sites of the small-sized LDH nanosheets (20–40 nm). All the catalysts exhibit excellent catalytic activities in air oxidation of benzyl alcohol without external base associated with the remarkable size- and active site structure-dependence. The catalyst Au38/LDH shows the highest activity with TOF of 1884 h−1, which can be attributable to the ultrafine bi-icosahedron structure Au38 NCs and the strongest Au38 NCs – Ni-OH (LDH) synergistic effect facilitating the activation of α-CH bond of benzyl alcohol over more negatively charged Au sites upon XPS, CO-DRIFTs and kinetic isotope studies. The findings of the size- and active site structure-dependence of supported Aun cluster catalysts in the oxidation of benzyl alcohol provide important guiding principles for the rational design of supported Aun cluster catalysts.

Levelized Cost of Charging Electric Vehicles in the United States

Summary The cost to charge an electric vehicle (EV) varies depending on the price of electricity at different charging sites (home, workplace, public), vehicle use, region, and time of day, and for different charging power levels and equipment and installation costs. This paper provides a detailed assessment of the current (2019) levelized cost of light-duty EV charging in the United States, considering the purchase and installation costs of charging equipment and electricity prices from real-world utility tariffs. We find national averages of $0.15/kWh for battery EVs and $0.14/kWh for plug-in hybrid EVs in the United States. Costs, however, vary considerably (e.g., $0.08/kWh to $0.27/kWh for battery EVs) for different charging behaviors and equipment costs, corresponding to a total projected fuel cost savings between $3,000 and $10,500 compared with gasoline vehicles (over a 15-year time horizon). Regional heterogeneities and uncertainty on lifetime vehicle use and future fuel prices produce even greater variations.

Nonlocal density functional theory of water taking into account many-body dipole correlations: binodal and surface tension of ‘liquid–vapour’ interface

In this paper we formulate a nonlocal density functional theory of inhomogeneous water. We model a water molecule as a couple of oppositely charged sites. The negatively charged sites interact with each other through the Lennard–Jones potential (steric and dispersion interactions), square-well potential (short-range specific interactions due to electron charge transfer), and Coulomb potential, whereas the positively charged sites interact with all types of sites by applying the Coulomb potential only. Taking into account the nonlocal packing effects via the fundamental measure theory, dispersion and specific interactions in the mean-field approximation, and electrostatic interactions at the many-body level through the random phase approximation, we describe the liquid–vapour interface. We demonstrate that our model without explicit account of the association of water molecules due to hydrogen bonding and with explicit account of the electrostatic interactions at the many-body level is able to describe the liquid–vapour coexistence curve and the surface tension at the ambient pressures and temperatures. We obtain very good agreement with available in the literature MD simulation results for density profile of liquid–vapour interface at ambient state parameters. The formulated theory can be used as a theoretical background for describing of the capillary phenomena, occurring in micro- and mesoporous materials.

Improved analysis methods to study the behavior of potassium ions in the interlayer of montmorillonite

The behavior of potassium chloride (KCl) as a main mud shale inhibitor remains poorly defined in the interlayer of montmorillonite (Mt). In this paper, a new analysis method of transmission electron microscopy-energy dispersive X-ray spectroscopy (TEM-EDS) was established. The distribution of K+ in the interlayer of Mt and the processes surrounding d-spacing shifts in Mt were investigated through X-ray diffraction and TEM-EDS. The experimental results revealed shoulder peaks in the diffraction patterns at KCl concentrations between 11% and 19%. The distribution of K+ varied in the inner and outer layers of Mt with different KCl concentrations. It could be concluded that the distribution of K+ and the changes in d-spacing of Na are determined by two factors: negative charge sites and concentration difference. When the KCl concentration was below 8%, both factors cause the outer layer of Mt to adsorb more K+ than the inner layer, with all layers exhibiting d-spacings within the 1.50nm state. At an 8% KCl concentration, all negative charge sites were occupied by K+. As the KCl concentration rose above 8%, the outer layer of Mt adsorbed more K+ than the inner layer due to the concentration difference. With a further increase in the KCl concentration, the d-spacing shifted linearly to 1.30nm from the outer to the inner layer of Mt. All layers of Mt exhibited a d-spacing of 1.30nm at KCl concentrations of up to 23%. These results demonstrate the benefits and capabilities of the proposed method in investigating the intercalating mechanisms of Mt.

Can Charging Infrastructure Used Only by Electric Taxis Be Profitable? A Case Study From Karlsruhe, Germany

Electric vehicles are a promising instrument for reducing greenhouse gas emissions and other local pollutants, such as nitrogen oxides. Especially the taxi sector is a promising field of application. First, their high driving distances are necessary for electric vehicles to economize against conventional vehicles. Second, taxis are operated predominantly in city centers, where the pressure to reduce local emissions is greatest. However, while the electrification potential of taxi fleets has gained great attention in literature, the question of whether charging infrastructure can be profitable if only used by taxis has not been answered yet. To answer this question, we analyze 161 taxis in Karlsruhe, Germany. We find that a high share of electric taxis would come at lower cost than their diesel counterparts. Thus, a 25–45% share of taxi driving could be electrified, if only the taxi user perspective would be taken into account. However, while ten charging sites would be necessary to do so, only one charging site could be refinanced through exclusive taxi use. Consequently, the electrification potential would fall to about 3%, if only this one profitable charging site was built. Yet, in the future, electric driving will become cheaper. In 2025, already 55% electrification potential would be possible, given that both electric driving and charging infrastructure operation would be profitable. Altogether, while currently taxi charging infrastructure would require public funding or other business models, in the medium to long term, an exclusive use by taxis would be sufficient.

Chlorine-doped carbon for electrocatalytic nitrogen reduction

The electrochemical reduction of stable dinitrogen (N2) molecules into value-added chemicals such as ammonia has been attracting substantial research interests recently, while the bottleneck of catalyst design exists in the rational synthesis of catalytic centers with efficient N2 chemisorption and subsequent activation. In this work, we demonstrated a facile approach of doping carbon black with a trace amount of chlorine, which allowed for the enhancement of its nitrogen reduction capability. Structural characterizations revealed the successful doping of the chlorine element into the carbon framework, accompanied by the polarization of the surface charge density. The positively charged carbon sites behaved as good NRR catalytic centers, with a maximum ammonia production rate of 4.3 μg h−1 cm–2 and a corresponding Faradaic efficiency of 7.2%, thus suggesting a potential approach for enhancing the nonmetal catalysts for electrochemical ammonia synthesis.

Quantum Mechanical Modeling of Reaction Rate Acceleration in Microdroplets.

Organic reactions in microdroplets can be orders of magnitude faster than their bulk counterparts. We hypothesize that solvation energy differences between bulk and interface play a key role in the intrinsic rate constant increase and test the hypothesis with explicit solvent calculations. We demonstrate for both the protonated phenylhydrazine reagent and the hydrazone transition state (TSB) that molecular orientations which place the charge sites at the surface confer high energy. A pathway in which this high-energy form transforms into a fully solvated TSB has a lower activation energy than bulk by some 59 kJ/mol, a result that is consistent with experimental rate acceleration studies.

Charge Anisotropy of Nitrogen: Where Chemical Intuition Fails

For more than half a century computer simulations were developed and employed to study ensemble properties of a wide variety of atomic and molecular systems with tremendous success. Nowadays, a selection of force-fields is available that describe the interactions in such systems. A key feature of force-fields is an adequate description of the electrostatic potential (ESP). Several force-fields model the ESP via point charges positioned at the atom centers. A major shortcoming of this approach, its inability to model anisotropies in the ESP, can be mitigated using additional charge sites. It has been shown that nitrogen is the most problematic element abundant in many polymers as well as large molecules of biological origin. To tackle this issue, small organic molecules containing a single nitrogen atom were studied. In performing rigorous scans of the surroundings of these nitrogen atoms, positions where a single extra charge can enhance the ESP description the most were identified. Significant improvements are found for ammonia, amines, and amides. Interestingly, the optimal location for the extra charge does not correlate with the chemically intuitive position of the nitrogen lone pair. In fact, the placement of an extra charge in the lone-pair location does not lead to significant improvements in most cases.

Transition Metal Dichalcogenide-Silk Nanofibril Membrane for One-Step Water Purification and Precious Metal Recovery.

With the rapid worldwide industrial development, large amounts of pollutants such as heavy metals are discharged into the water sources, causing a huge threat to living beings. To mitigate this issue, there is an urgent need for new water treatment strategies. Inspired by a natural shell nacre structure and a multidimensional hybrid concept, we demonstrate multilayered inorganic-organic hybrid membranes using metallic molybdenum disulfide (MoS2) as two-dimensional transition metal dichalcogenide nanosheets and one-dimensional silk nanofibrils for water purification. Because of its possessing negatively charged layers and interaction sites, the hybrid film could adsorb metal ions and dyes from water. The separation performance can be tuned by changing the component ratios of these two nanomaterials. During filtration, due to the reducing effect of the MoS2 nanosheets, precious metal ions are reduced to their nanoparticle form without any further thermal or chemical treatments. In addition to the one-step removal and recovery of metal ions, the hybrid membranes exhibit excellent potential for the determination and removal of different dyes from water. The results of this research can open up an effective and green avenue for water purification and recovery of metal ions dissolved in water.

Quantification of peak shaving capacity in electric vehicle charging – findings from case studies in Helsinki Region

An increasing share of electric vehicles can mean excessive peak loads in low-voltage power distribution networks. Introducing peak shaving mechanisms to the charging systems, such overloads can be mitigated significantly. The first contribution of this study is to quantify the amount of flexibility that electric vehicles can contribute to peak load reduction so that the drivers can still fully charge the batteries of their vehicles. The second contribution is that the study presents and compares two optimisation strategies for peak load reduction. The work is based on real charging data covering about 25,000 charging sessions at various charging sites in the metropolitan area of the Finnish capital city. The main finding is that the peak loads at charging sites can be reduced by up to 55%. Another important result is that load reduction through low-power charging is achievable only if the average parking time at the charging site is >3 h, without affecting the user experience negatively. It is also found out that the average parking time is over 2 h longer than the average charging time, which indicates the enormous potential of electric vehicles in peak shaving.