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Vanadium redox flow battery (VRB), as the most promising large-scale electrical energy storage units, has attracted extensive attention. Amphoteric ion exchange membrane (AIEM), as the core part of VRB, separates electrolyte on both sides of electrolytic tank and conducts H+. The AIEM with cation and anion groups possesses excellent performances, such as high ion conductivity (σ), low vanadium ion permeability (PVn+), relative stability and low cost. However, the performance of AIEM directly depends on the chemical structure of polymers. In addition to ensuring foundational physical performance, ion selectivity of AIEM is significant since the crossover of vanadium ion with various valences may reduce the battery capacity. In this paper, AIEMs for VRB and their chemical structures as well as synthesis approaches to realize all kinds of high-performing AIEMs are reviewed. The current trend and future direction of prospective materials for the VRB separators are documented in detail as well.

With very fast polymerization in mild reaction conditions and unique characteristic of double bonds in its synthesized polymer skeleton for further modification and functionalization, ring opening ...

One of the characteristics of implementing an independent curriculum is student-centered learning. The term in the independent curriculum is closely related to the philosophy of Education Ki Hajar Dewantara, namely the curriculum that servitudes children. This philosophy starts from the learning objectives, planning, implementation, and assessment system as well as the evaluation of Learning in the Early Childhood Education environment is the responsibility of the teacher for the results of activities achieved by students. The teacher is tasked with measuring whether students have achieved proper development from 5 (five) aspects of basic skills, including religious and moral, cognitive, social-emotional, language, and physical motor also child growth, including weight, height, head circumference, and upper arm circumference. The initial assessment aims to uncover and recognize the characteristics of learners, identifying learners' competencies, strengths, and weaknesses. The results are used by educators as a reference to plan a learning process according to learning needs. This research shows that the initial management of 'School Mover' and 'Non-School Mover' requires management in its implementation and it is integrated part of the learning process in realizing the Pancasila Student Profiles.

Graphene (Gr) and its derivatives (such as graphene oxide (GO), reduced graphene oxide (RGO), nanoparticles decorated graphene, etc.) reinforced metal matrix composites (MMC) with good structural mechanical properties and functional properties have wide applications in aerospace, automotive, electronics and military fields. However, some problems exist in preparing high performance MMC including poor wettability between Gr-type fillers and metal matrix, and weak interfacial bonding strength. Efficient methods for preparing Gr-related nanomaterials filling metal matrix parts with high performance, especially for complex parts still need be further developed. The engineering application field of Gr MMC needs to be further expanded. In this paper, methods to prepare high performance MMC including surface modification of Gr and its derivatives, properties and applications of these reinforced MMC were reviewed with detailed examples. The main challenges were analyzed and the development trend of Gr-type types reinforced MMC was discussed.

Small specific surface area as well as fast recombination rate of photoelectron–hole pairs deteriorated the photocatalytic performances of carbonitride carbon (g-C3N4) in solving environmental pollution and energy crises. In this study, cuprous oxide (Cu2O) nanocubes grew on the g-C3N4 porous nanosheet to form a n–p nanoheterostructure. This unique structure of the prepared g-C3N4/Cu2O photocatalyst resulted in the photogenerated electron–hole pairs having enhanced separation rates. Under visible light irradiation, heterojunction degradation ability of methyl orange was significantly increased and its enhanced mechanism was systematically studied.

Resistance spot welding of dissimilar materials (AISI-1008 steel and aluminium-1100 alloy) by adding an interlayer of graphene nanoplatelets (GNPs) is reported in this study. This GNP layer is incorporated in the steel plate by drop-coating technique and the coated steel and the aluminium plates were joined by the resistance spot-welding method. The peak loads of these dissimilar lap joints processed at different welding current/time conditions were obtained by lap-shear tests and a comparative study was carried out between the GNP coated and bare specimens. While the weld strength depends predominantly on the time/current used for the welding, a maximum enhancement of ∼124 % is obtained for GNP coated samples in comparison to that of the bare ones. Fractography was performed by SEM and it was observed that a mixture of both brittle and ductile fractures was the major cause of failure. Interfacial failure and metal expulsion were also observed at lower and higher processing conditions respectively. Nugget size variation with different processing parameters was also studied. Dissimilar metal welding formed Al-Fe rich intermetallics (FeAl3, Fe2Al5, and Fe4Al13) which enhanced some of the properties of the nano-composites formed in the nugget zone. Detailed microstructural characterization was carried out by light microscopy, AFM, SEM, TEM, XRD and Raman spectroscopy. The enhancement of strength of the composite was done by numerous strengthening mechanisms as a result of the incorporation of GNPs. Micro-hardness investigation across the weld cross-section was carried out and it was found that an enhancement in hardness due to the formation of intermetallics and graphene entrapment was reported.

Cu2Nb34O87 with an inverse opal morphology is fabricated, showing highly-ordered macropores with sizes of ∼170 nm and walls with thicknesses of 20–30 nm. This first-reported Cu2Nb34O87 nanomaterial exhibits good Li+-storage properties, including a large capacity, safe operating potential, large initial coulombic efficiency, high rate performance and good cycling stability.

Ionogels have aroused wide interests in the field of flexible electronics. The combination of solid-state networks and ionic liquids opens up thousands of possibilities for ionogels. The unique structures of ionogels endow them excellent mechanical properties, conductivity and thermal stability to approach the challenge of flexible electronic. A large number of new ionogels have been developed by different methods including the exchange of solution, polymeric ionic liquid and in-situ reactions in ionic liquids (gelation of low molecular weight gelators, self-assembly of block polymers, formation of double-network structure, ionogel nanocomposites and direct polymerization of polymerizable monomers). The aim of this review is to discuss different preparation methods of ionogels and the comparison of their advantages.

Lignin is a widely used adsorbent for removing heavy metal ions from water. Lignin can be extracted from black liquor and its inert surface properties limit its adsorption performance. In this paper, a new type of modified lignin adsorbent doped with Cu/N was prepared by the reaction of lignin with triethylenetetramine (TETA) and CuCl2. The adsorption capacities of the Cu/N-doped lignin (Cu/N-Lignin) adsorbents, N-doped lignin (N-Lignin) adsorbents and undoped lignin (U-Lignin) on three anions (As (V), Cl− and Cr (VI)) were systematically studied. In the solution with these three mixed ions, the removal rate of the Cu/N-Lignin adsorbents on As (V), Cl− and Cr (VI) was 86.44%, 0% and 39.48%. The adsorption capacity of Cu/N-Lignin to As(V) was 253.5 mg/g. Under the same adsorption conditions, the selectivity of the Cu/N-Lignin adsorbents to anions was Cl−

Novel waterborne acrylic resin modified by cellulose acetate butyrate was successfully synthesized by a homogeneous solution polymerization with 2-butoxy ethanol, cellulose acetate butyrate and acrylic monomers as raw materials, N, N - dimethyl ethanolamine as neutralization and γ-aminopropyltriethoxysilane (KH-550) as curing agent. The influences of the cellulose acetate butyrate and curing agent content on the properties of the waterborne acrylic resin were investigated. As a curing agent, KH-550 not only improved the cross-linking density of the resin effectively, but also bonded to the substrate to form a molecular layer of silane. Cellulose acetate butyrate and KH-550 were found to reduce the curing temperature of the resin. The tensile strength of the coating added with the curing agent (5.89 MPa) was significantly improved compared to that of cellulose acetate butyrate modified resin (1.49 MPa). This kind of environment-friendly waterborne acrylic resin has a strong potential application in wood coatings, automobile coatings and other fields.

The hydrogen evolution reaction, 2H(+) + 2e(–) → H2, and its converse, the hydrogen oxidation reaction, H2 → 2H(+) + 2e(–), are central to any realization of a hydrogen economy. Various forms of carbon have been used for decades as the precious metal catalyst support in these reactions. Here we report the unexpected result that single-wall carbon nanotubes and some graphitic carbons, activated by brief exposure to electrochemical potentials that induce hydrogen evolution in intercalating acids combined with extended soak times in such acids, acquire an activity for these reactions that exceeds that of known nonprecious metal catalysts.

Exposure of single-walled carbon nanotubes (CNTs), as well as other lower cost layered graphitic carbons (LGCs), to acidic intercalants, in combination with low voltage electrochemical cycling, induces in these materials hydrogen evolution activity that initiates at near zero overpotential and is on par with that of platinum catalysts.1 These results encouraged the further development and testing of the CNT catalyst in a PEM water splitting electrolyzer prototype. Once activated, the CNT cathode demonstrated 1 A/cm2 of HER current at 1.64 V, comparable to a similarly tested commercial Pt-loaded cathode. While carbon nanotubes are not intrinsically scarce, the single wall nanotubes used in these electrode tests remain relatively expensive. Commercial significance would benefit from a demonstration of comparable performance from activated lower cost layered graphitic carbons in a PEM electrolyzer prototype. The following LGC materials, having a combination of high electrical conductivity, large pore volumes, and high specific surface areas, were tested in terms of their ability to achieve low HER overpotential during the activation process: microcrystalline graphitic particles, Vulcan XC-72 carbon, highly graphitized stacked-cup tubular carbon nanofibers (CNFs), and carbon needle felt. CNF electrodes demonstrated slightly higher mass basis activity than that of the other tested LGCs in acid electrolyte in a standard three-terminal electrochemical cell. Here we report excellent performance from activated CNF cathodes, prepared by a scalable spray-coating method, in our PEM electrolyzer prototype (IrRuOx as anode catalyst). As anticipated, a control MEA, based on the non-activated CNF cathode and tested in PEM electrolyzer under identical conditions, showed poor performance, indicating a low electrocatalytic HER activity of the electrode. The activated CNF cathode-based PEM electrolyzer achieved 1 A/cm2 at 1.78 V, while a control commercial MEA with Pt-loaded cathode/IrRuOx anode (a high Pt catalyst loading of 3 mg/cm2 cathode, Fuel Cells Etc) tested in the same PEM electrolyzer cell demonstrated 1 A/cm2 at 1.7 V. Acknowledgements. This work is supported by Amazon through ECS Amazon Catalyst Program. References: R. K. Das, Y. Wang, S. V. Vasilyeva, E. Donoghue, I. Pucher, G. Kamenov, H.-P. Cheng, A. G. Rinzler, ACS Nano, 2014, 8 (8), 8447–8456.

Pasteurella multocida has been recognized as an important veterinary pathogen for over a century. Conventional methods for diagnosis of pasteurellosis rely on the detection of the organism by microscopy and its isolation and identification. However, as far as pasteurellosis is concerned, it is not just sufficient to know the identity of the organism. To constitute effective control measures, it is important to know the serotype of the organism. A study was undertaken to characterize the Pasteurella isolates from local pigs in India with clinical respiratory disease by determination of their capsule types and presence or absence of toxin gene. Pasteurella could be isolated from 66.70% of pigs with clinical respiratory disease. All the isolates were confirmed through biochemical characterization and P. multocida-specific polymerase chain reaction. It has also been observed that all the isolates belonged to capsular type D. All the isolates were sensitive to chloramphenicol, chlortetracycline, doxycycline, and enrofloxacin, while the rest of the antibiotics were less effective. It has also been observed that all isolates were resistant to cephalexin, penicillin G, and sulphadiazine. The study revealed the detection of P. multocida serotype D from clinical respiratory diseases of local pigs of India, which could be one of the important respiratory tract pathogens responsible for mortality of local pigs in India.

This paper reports a novel supercapacitor electrode design based on poly(3,4-propylenedioxypyrrole) (PProDOP) electropolymerized onto thin films of single walled carbon nanotubes (SWNTs) on glass substrates. This permits the electropolymerization of thicker PProDOP films than can be deposited onto flat gold-coated Kapton electrodes and a correspondingly greater capacitance per unit area. A pyrene functionalized polyfluorene, designated Sticky-PF, was designed and used as an effective monolayer interfacial adhesion modifier between the SWNT films and PProDOP via noncovalent self-assembly onto the SWNT film surfaces before polymer electrodeposition. The thickness of the electrodeposited PProDOP was found to be self-limiting at thicknesses characteristic of each substrate electrode. Optimized areal capacitance values for PProDOP on flat gold and Sticky-PF coated SWNT films were measured to be 8.1 mF/cm2 and 16.4 mF/cm2, respectively, with the twofold enhancement due to the thicker films possible on the SWNT ...

Anticipated increases in worldwide energy consumption, the reality of ultimately limited hydrocarbon fuels, as well as their contribution to global warming, have all encouraged the development and commercialization of renewable, carbon neutral, energy technologies. An issue for renewable energy sources like solar, wind and wave energy is their intermittency. An efficient means to overcome this intermittency is to build excess capacity into the generating plants and to use that excess capacity to produce high energy density hydrogen fuel via water electrolysis for on demand reconversion to electrical energy in fuel cells. A major impediment to this solution is that commercial water splitting electrolyzers use scarce and costly precious metal catalysts which make such an energy storage/recovery scheme prohibitively expensive. Alternative, earth-abundant, non-precious metal catalysts are highly desired. We recently demonstrated that purified single wall carbon nanotubes (SWNT), and select layered graphitic materials, activated by a simple electrochemical process, provide an exceptional non-precious metal electrocatalyst for the hydrogen evolution and the hydrogen oxidation reactions in both acidic and near neutral pH. [1] Here we validate this result for hydrogen evolution in a single-cell PEM electrolyzer. The MEAs studied used Nafion 115 and an IrRuOx anode. Three distinct cathodes were tested: 1) commercially available Pt loaded (3.0 mg/cm2) Vulcan X-72 carbon (for a point of comparison); 2) non-activated SWNTs; and 3) activated SWNTs. In all cases I-V measurements were performed at 80oC. The commercial Pt loaded MEA exhibited the high gas production rates expected from engineered Pt, converting 1.0 A/cm2 at 1.67 V. The non-activated SWNTs yielded very low gas production rates requiring 1.89 V for a current of only 0.040 A/cm2. The activated SWNTs demonstrated a performance completely comparable, at all potentials, with that of the commercial Pt electrode (see Figure), attaining 1.0 A/cm2 at 1.64 V. Ninety hours of operation showed no degradation in the cathode performance. It has been estimated that a 50% reduction in the cathode Pt used would result in a 15% electrolyzer cost reduction. [2] Our entirely Pt–free electrode using only earth abundant carbon could nearly double that cost saving. Acknowledgements. This work was supported by Nanoholdings, LLC. References: [1] R. K. Das, Y. Wang, S. V. Vasilyeva, E. Donoghue, I. Pucher, G. Kamenov, H.-P. Cheng, A. G. Rinzler, ACS Nano, 8 (8), 8447–8456 (2014) [2] K. E. Ayers, E. B. Anderson, C. B. Capuano, B. D. Carter, L. T. Dalton, G. Hanlon, J. Manco, and M. Niedzwiecki, ECS Transactions, 33 (1), 3-15 (2010) Figure 1

This paper investigates an approach for making comparison of seismic evaluation and corresponding costs according to design of concrete frames in different seismic zones of Bangladesh. Bangladesh, one of the world’s most densely populated countries with lower medium income, is vulnerable to earthquake hazards for its geological position. It is surrounded by Himalayan Arc, Shilong plateau in the north, the Burmese Arc, Arakan Yoma anticliorium in the east and complex Naga-Disang-Jaflong thrust in the northeast which has made it suited to earthquake. Similarly, the Dauki Fault system along with numerous subsurface actives faults and flexure zone called Hinge Zone raises the earthquake risk factor higher. Therefore, the construction of multistoried building in the different seismic zones (Zone I, Zone II, Zone III) of Bangladesh seek several attention for making it stable to sustain the high magnitude of earthquake with economical design practice. A well known fact is that a code based high-rise construction not only safe for living but it also lessens the construction cost. In this research, it has been represented a comparative study of lateral displacement due to earthquake, construction cost and reinforcement consumption for building construction in different categories of multistoried building in the three seismic zones of Bangladesh. In the present study, earthquake load has been assigned by factorizing with specific zone factor for every zone. Finally, after conducting standard costing and estimation, it has been found that, it increases the cost of construction and amount reinforcement dramatically in the high seismic zone along with high lateral displacement as compared to the other earthquake zone.

A key advantage of bulk nanoscale materials in applications ranging from energy storage to chemical catalysis is their inherent high surface area. Single-wall carbon nanotube films possess the additional advantages of high electrical conductivity and robust mechanical integrity. Nevertheless the flexibility of the individual nanotubes and their affinity for each other conspire to obstruct the porosity in such films limiting the perfusion rate of liquids and gases, restricting the accessible surface area and thereby limiting their utility in important applications. Here we demonstrate a simple, effective means to engineer controlled porosity into the nanotube films. The newly incorporated porosity modifies the film electrolytic capacitance and comparative perfusion rates. Pseudocapacitive RuO(2) electrodeposited onto the highest porosity films exhibits a specific capacitance of 1084 F/g. Knowledge of the underlying nanotube capacitance and mass permits extraction of the deposited RuO(2) specific capacitance of 1715 F/g, which closely approaches the predicted theoretical maximum RuO(2) capacitance of 2000 F/g.

An adaptation of the famous Stern-Gerlach experiment has found important applications to nanomagnetism. A beam of magnetic clusters is sent in a projectile through an inhomogeneous magnetic field and the resultant deflected spots are collected on a detector screen. The difference with the historic experiment is that the beam deflection during the traversal through the magnetic region is influenced by rotational diffusion of the magnetization vector across an anisotropy barrier. In this paper we provide a complete analysis of the line profile of the deflected spots and a detailed comparison with experimental data.

The hydrogen evolution reaction, 2H+ + 2e- -> H2, has utility in the electrochemical production of hydrogen from water and is perhaps the most studied reaction in all of electrochemistry. Its converse, the hydrogen oxidation reaction, H2 -> 2H+ + 2e-, is the half cell reaction occurring in hydrogen fuel cells, which, by direct conversion of chemical to electrical energy avoids the Carnot efficiency limits intrinsic to heat pumps. These reactions are central to any realization of a hydrogen economy. Various forms of carbon have been used for decades as the precious metal catalyst support in these reactions. Here we report the unexpected result that single wall carbon nanotubes (SWNTs), can be activated by a simple process to exhibit an activity for these reactions, in acidic and pH neutral electrolytes, that exceeds that of all known non-precious metal catalysts. We have labored to exclude conventional metals as the source of this activity and concluded that it is due to the SWNTs themselves.

Present study describes the skin folding pattern in Ghungroo pig, indigenous breed well known for its high prolificacy and adaptability under low input production system in North Eastern region of India. The distribution of skin folds was observed in forehead, back, flank, ham and lower hind region and their thickness was varied from 6.25 mm to 29 mm and number ranged from 3 to 7 at different body parts of pig. The most predominant site for skin fold formation was forehead and flank region followed by back and ham. The skin folding at forehead region predisposes the maggot wound formation which affects the gross productivity of this indigenous pig. The development of skin fold was not associated with nutritional status as it was observed in both sexes and irrespective of body condition score (BCS) ranging from ≤2.5 to ≤4.5. Therefore, exploration of genetic involvement with this trait should be considered for further study for saving the Ghungroo breed with full production potential.