Organic Carrier Research Articles

Promoting Morphology with a Favorable Density of States Using Diiodooctane to Improve Organic Photovoltaic Device Efficiency and Charge Carrier Lifetimes

Due to the inherent challenges in probing nanoscale properties within bulk heterojunction (BHJ) active layers of organic photovoltaic (OPV) devices, the relationship between morphology and nanoscale electronic structure is not well understood. Here, we employ scanning tunneling microscopy (STM) dI/dV imaging and localized density of states (DOS) spectra to investigate the influence of additives on morphology in a high-performance OPV system. In short, we are able to correlate the use of diiodooctane (DIO) additive with significant changes to the distribution of the localized DOS, most notably a broader distribution of PCE10 polymer HOMO levels and PC70BM fullerene LUMO levels, as well as significantly smaller domain sizes and significantly higher overall device efficiencies. We further correlate this data with a nearly 3-fold increase in charge carrier lifetimes in the active layer when DIO is employed, determined by time-resolved microwave conductivity (TRMC) measurements. The results are consistent with...

Trichoderma atroviride TRS25 isolate reduces downy mildew and induces systemic defence responses in cucumber in field conditions

In an attempt to reduce the impact of downy mildew progress during cucumber cultivation and to improve plant growth, the efficacy of bio-agent Trichoderma atroviride TRS25 was evaluated in open field conditions. Two application forms of TRS25 were used: (i) dried conidia for seed coating, (ii) fungal biomass on organic carrier for soil application. The experiment was conducted for three years. The effect of TRS25 on cucumber germination, early plant growth, cucumber yield, rhizosphere colonization and downy mildew development were measured. To confirm the early evidence of induced resistance in plants caused by TRS25, the changes in hydrogen peroxide, lipid peroxides, phenolic compounds concentrations and the phenylalanine ammonia lyase, guaiacol peroxidase and ascorbate peroxidase activities in plant leaf tissues were estimated.Seed coating with TRS25 significantly improved cucumber germination, enhanced vegetative plant growth and reduced downy mildew infection, compared to untreated plants. Soil application of Trichoderma with organic carrier was disadvantageous for cucumber production, because of phytotoxic effect of the carrier. However, both forms of TRS25 application significantly reduced downy mildew and activated systemic defence responses in cucumber plants. The fungus was also able to colonize the rhizosphere. The results suggest that T. atroviride TRS25 may be used to improve plant resistance in integrated plant protection program.

Impact of chronic high fat diet consumption on the expression of organic nutrients carriers in the small intestine of mice: role of thyroid hormones in these processes

Searchable abstracts of presentations at key conferences in endocrinology ISSN 1470-3947 (print) | ISSN 1479-6848 (online)

Dual functional hybrid-polyoxometalate as a new approach for multidrug delivery

Herein, a new antitumor active polyoxometalate, (TBA)4H3[GeW9V3O40], has been introduced as an inorganic drug with enormous influence on brain cancer cells and its outstanding results against U87 cells have been described. Post-functionalization of this polyoxometalate produces a drug delivery vehicle which comprises both kinds of inorganic and organic drugs. This system is consisted of mesoporous silica nanoparticles as organic drug carrier, along with redox-responsive disulfide bonds for drug release into the cell at the same time. Moreover, a fluorescence dye has been attached to the polyoxometalate that allows for tracking the drug into the cell environment. This dual-functionalized polyoxometalate was utilized in a designed multidrug delivery system, and worked greatly against U87 cells and knocked down these cancer cells up to near 70% in 48 h. Due to its unique properties, this multidrug delivery vehicle is potent to be developed and used for various applications in cancer therapy.

Semi-preparative asymmetrical flow field-flow fractionation: A closer look at channel dimensions and separation performance

The design and performance of a semi-preparative asymmetrical flow field-flow fractionation (SP-AF4) channel are investigated with the objective of better understanding and exploiting the relationship between channel dimensions, sample loading, and resolution. Most size-based separations of nanometer and submicrometer particles are currently limited to analytical scale quantities (<100μg). However, there is a strong need to fractionate and collect larger quantities so that fundamental properties of the more narrowly dispersed fractions can be studied using additional characterization methods and for subsequent applications. In this work, dimensions of the spacer that defines the form of SP-AF4 channels are varied and their performances are assessed with respect to sample focusing position and loading. Separations are performed in aqueous and organic carrier fluids. A critical evaluation of channel dimensions showed that increasing the channel breadth is a practical and effective route to maintaining separation resolution while increasing sample loads to milligram quantities. Good size resolution (∼1.0) is achieved for separations of 10mg of 50 and 100nm silica nanoparticles suspended in water and up to 0.6mg of ∼10 to 35nm inorganic hybrid nanoparticles suspended in tetrahydrofuran. This work represents important advances in the understanding of SP-AF4 separations and extends sample loading capacities in both aqueous and organic solvents.

Model of the regulation of activity of immobilized enzymes (amylases) in soil

The preservation of activity of extracellular enzymes in soil is presently associated with their immobilization on organic or inorganic carriers. Enzyme immobilization results, however, in a significant decrease in enzymatic activity. In the present work, the mechanism responsible for promotion of the catalytic activity was revealed, as well as the favorable effect of low-molecular alkylhydrozybenzenes of the class of alkylresorcinols, which are common in soil organic matter, on stability of immobilized enzymes (exemplified by amylases) by their post-translational modification. Optimal conditions (enzyme to sorbent ratio, pH optimum, CaCl2 concentration, and sorption time) for amylase sorption on a biological sorbent (yeast cell walls) were determined and decreased activity of the immobilized enzyme compared to its dissolved state was confirmed. Alkylresorcinols (C7AHB) at concentrations of 1.6 to 80 mM were found to cause an increase of amylase activity both in the case of already sorbed enzymes (by 30%) and in the case of a free dissolved enzyme with its subsequent immobilization (by 50–60%). In both cases, the optimal C7AHB concentration was 16 mM. Amylase stability was determined for C7AHB-modified and unmodified enzymes immobilized on the biological sorbent after two cycles of freezing (–20°C) and thawing (4°C). Inverse dependence was revealed between increasing stability of C7AHB-modified enzymes and an increase in their activity, as well as higher stability of immobilized modified amylases than of the dissolved modified enzyme. Investigation of the effect of C7HOB-modification in the preservation of activity in immobilized amylases after four freeze–thaw cycles revealed: (1) better preservation of activity by the modified immobilized enzymes compared to immobilized ones; (2) differences in the dynamics of activity loss within compared pairs, with activity of immobilized amylases decreasing after the second cycle to a lower level (42%) than activity of the modified immobilized enzymes after the fourth cycle (48%). These results demonstrate that in the preservation of activity of extracellular enzymes in soil both stabilization mechanisms are of importance: immobilization on organic carriers and modification of the enzyme conformation by low-molecular compounds with the functions of chemical chaperones.

EUnaG: a new ligand-inducible fluorescent reporter to detect drug transporter activity in live cells

The absorption, distribution, metabolism and excretion (ADME) of metabolites and toxic organic solutes are orchestrated by the ATP-binding cassette (ABC) transporters and the organic solute carrier family (SLC) proteins. A large number of ABC and SLC transpoters exist; however, only a small number have been well characterized. To facilitate the analysis of these transporters, which is important for drug safety and physiological studies, we developed a sensitive genetically encoded bilirubin (BR)-inducible fluorescence sensor (eUnaG) to detect transporter-coupled influx/efflux of organic compounds. This sensor can be used in live cells to measure transporter activity, as excretion of BR depends on ABC and SLC transporters. Applying eUnaG in functional RNAi screens, we characterize l(2)03659 as a Drosophila multidrug resistant-associated ABC transporter.

Wear and Friction of Greases Containing Organic and Inorganic Sulfur Carriers

Wear and Friction of Greases Containing Organic and Inorganic Sulfur Carriers

Molecular Dynamics of the Assembly Modes of the Oligothiophene Polymers with Different Chain Lengths

The spatial packing modes of organic hole transporting materials exert a significant effect on the charge mobility. However it is difficult to reasonably design the materials with high-charge transfer performances due to the limits of the data regarding crystal structures. In this work, molecular dynamics simulation was used to find the new spatial packing ways of organic photoelectric materials containing oligothiophene based on randomly distributed initial structures. This work lays a theoretical foundation for designing favorable organic carrier transporting materials.

Energy conservative brown coal conversion to hydrogen and power based on enhanced process integration: Integrated drying, coal direct chemical looping, combined cycle and hydrogenation

An integrated system for converting brown coal to H2 and power is proposed. This system consists of coal drying, coal direct chemical looping, combined cycle, and hydrogenation. The energy involved in each module is recirculated thoroughly before it is integrated with the other modules, meaning that any unrecoverable energy can be utilized in other modules. In coal direct chemical looping, three continuous reactions are employed, namely, reduction, oxidation, and combustion. Iron oxide is used here as the oxygen carrier that is recirculated among the reactors. Toluene is adopted as the organic carrier in the hydrogenation process, reacting with H2 to produce methylcyclohexane. We evaluated the performance of the system through a selection of operating conditions. The effect of the carbon conversion efficiency during the reduction was also clarified. The proposed system achieved high values for the production of H2 and power generation efficiencies, which are 71.4% and 19.9%, respectively.

Clean Co-production of H2 and power from low rank coal

This work proposes a state-of-the art integrated system for the co-production of H2 and power from low rank coal with high total energy efficiency. A model of this system is developed based on enhanced process integration technology, incorporating coal drying, gasification, chemical looping, power generation, and hydrogenation. In this model, heat circulation and process integration technologies are effectively combined, minimizing the exergy losses. Iron-based materials are used as oxygen carriers and are circulated in a chemical looping module consisting of three continuous processes: reduction, oxidation, and combustion. The toluene-methyl cyclohexane system is employed as a liquid organic H2 carrier to store H2 generated from coal. The effects of the fluidization velocity in drying, the steam-to-fuel ratio in gasification, and the chemical looping pressure are evaluated with regard to the power generation and H2 production efficiencies as well as the overall efficiency, and the proposed integrated system exhibits very high efficiencies of approximately 12, 72, and 84%, respectively.

Safety of Intra-Articular Implantation of Oligo[Poly(ethylene glycol) Fumarate] Scaffolds into the Rabbit Knee.

Implantable biomaterials supporting extended release of pharmacologic agents may permit localized intra-articular delivery of drugs that modulate the fibrotic response to injuries and surgery. Oligo[poly (ethylene glycol)] fumarate (OPF) is an attractive organic carrier, but its safety profile within synovial joints remains unclear. Here, we assessed the safety of OPF sponges using a validated in vivo model of knee arthrofibrosis. A cohort of 102 rabbits was divided into five groups: arthrotomy only (24), arthrotomy with OPF scaffold placement (24), surgically induced contracture (24), surgically induced contracture with OPF scaffold placement (24), and control without any surgical intervention (6). Six rabbits per surgical group were sacrificed at 72 h, 2, 8, and 24 weeks. Outcomes included biomechanical testing of range of motion, histologic analysis of synovial and cartilage tissues, and scaffold degradation. Cartilage histology and biomechanical measurements were comparable between groups with and without OPF. Synovial inflammation scores were similar among most groups with a minimally elevated score in the rabbits with arthrotomy and OPF versus those with arthrotomy alone. Scores for synovial tissues in rabbits with contracture and OPF were clinically equivalent to those with contractures alone. Most animals (92%) retained scaffold fragments at 24 weeks. Thus, OPF scaffolds implanted into native or arthrofibrotic rabbit knees neither induce nor aggravate cartilage damage, synovial inflammation, or contractures. The apparent safety of OPF scaffolds suggests that they are suitable carriers for the controlled delivery of reagents into the intra-articular joint space to treat arthrofibrosis.

Carbon Dioxide to Methanol: The Aqueous Catalytic Way at Room Temperature.

Carbon dioxide may constitute a source of chemicals and fuels if efficient and renewable processes are developed that directly utilize it as feedstock. Two of its reduction products are formic acid and methanol, which have also been proposed as liquid organic chemical carriers in sustainable hydrogen storage. Here we report that both the hydrogenation of carbon dioxide to formic acid and the disproportionation of formic acid into methanol can be realized at ambient temperature and in aqueous, acidic solution, with an iridium catalyst. The formic acid yield is maximized in water without additives, while acidification results in complete (98 %) and selective (96 %) formic acid disproportionation into methanol. These promising features in combination with the low reaction temperatures and the absence of organic solvents and additives are relevant for a sustainable hydrogen/methanol economy.

Extraction and Transport of Humic Acid using Supported Liquid-Membrane Containing Trioctyl Phosphine Oxide (TOPO) as the Carrier

or liquids of percolation from the discharges (leachates) are charged bacteriologically and especially chemically of mineral substances (mineral ions and heavy metals) and organic (volatile fatty acids, humic substances), which can contaminate soil, surface waters and ground waters. The humic substances, called also refractories, are not easily biodegradable and require concentrating them and/or adsorbing them by implementation of expensive processes. Scientists are looking for alternatives to eliminate or recover these substances. The present study investigates the elimination of humic acid from waste water using supported liquid membrane containing trioctyl phosphine oxide (TOPO) in toluene, as extractant. The supported liquid membrane is composed of a flat sheet of cross-linked polydimethylsiloxane (PDMS). In this study we have: (i) optimized the conditions for humic acid species transfer from feed aqueous phase to stripping phase across PDMS/TOPO/toluene supported liquid membrane; (ii) characterized the membrane by using FTIR technique and by determining the flux J, permeability P and diusion coecient of the complexed species D. Speciation of the humic acid species in the membrane organic carrier (extractant) phase has also been carried out using theoretically derived equations to elucidate the stoichiometry and mechanism of transport of humic acid across the PDMS/TOPO/toluene supported liquid membrane. Optimum conditions of transport for humic acid have been found to be: pH=3, [NaOH]=0.4 M, Eextraction = 94:67%, Ediusion = 32:5%, J = 1:34 10 4 mgcm 2 s 1 , D = 1:16 10 2 cm 2 s 1 and P = 2:64 cms 1 . Kinetic parameters calculated from the experimental data have been determined. Thermodynamic functions of the several species transfer from the feed solution to the stripping one through the supported liquid membrane, such us enthalpy, entropy and Gibbs free energies, were determined. Positive values of H and negative values of G indicate respectively the endothermic and the spontaneous nature of the humic acid extraction in aqueous solution.

ORGANIC DEVICES. Avoid the kinks when measuring mobility.

Transistor measurements can overstate organic semiconductor charge carrier mobility

Eradication of Sclerotinia sclerotiorum Sclerotia from Soil Using Organic Waste Materials as Trichoderma Fungi Carriers

Abstract Sclerotinia sclerotiorum (Lib.) de Bary is considered as one of the most harmful soilborne pathogens, which reduces productivity of horticultural crops. Currently used chemical or biological methods for the eradication of S. sclerotiorum from a soil are not very effective. The aim of this study was to evaluate the possibility of eradication of S. sclerotiorum sclerotia from a soil using the Trichoderma isolates, which were multiplied on the organic carriers prepared from agro-industrial wastes and by-products: WsA (wheat straw + apple pomaces), WsP (wheat straw + potato pulp) and T-GRAN (dry onion rind, apples and strawberry pomaces, rapeseed meal). The results showed that soil amendment with organic materials overgrown with the Trichoderma fungi had a significant reducing effect on S. sclerotiorum. Especially effective was the carrier WsA overgrown with T. virens TRS114, which completely prevented the survival of sclerotia of S. sclerotiorum regardless of the dose of application. Less effective was the WsP carrier. However, addition WsP overgrown with T. atroviride TRS40 at the 5% w/v, resulted in survival only 6.7% of sclerotia. In the greenhouse experiments with lettuce, the application of granulates T-GRAN into the soil had different impact on S. sclerotiorum depending on the conditions to the pathogen development. In conducive conditions, an addition of the organic substances without Trichoderma significantly decreased the yield of lettuce plants. A positive effect on the growth of plants was observed after the application of T-GRAN overgrown with Trichoderma.

Hydrogen storage and release from a new promising Liquid Organic Hydrogen Storage Carrier (LOHC): 2-methylindole

We report a new promising Liquid Organic Hydrogen Storage Carrier (LOHC): 2-methylindole in this paper, which has a hydrogen storage capacity of 5.76 wt%. The hydrogenation of 2-methylindole was carried out over a 5 wt% Ru/Al2O3 catalyst in a temperature range of 120–170 °C and a pressure of 7 MPa. The results indicate that the hydrogenation reaction rate increases dramatically with the increase of reaction temperature. The apparent activation energy was found to be 21 kJ/mol. The dehydrogenation of the hydrogenated product 8H-2-methylindole was carried out over a 5 wt% Pd/Al2O3 catalyst at 160–200 °C and 1 atm. Fully dehydrogenation was achieved within 4 h at 190 °C without any side reaction.

Evaluation of antibacterial activity of Stenotrophomonas maltophilia against Ralstonia solanacearum under different application conditions.

The aim of this study was the monitoring of different mechanisms involved in the antibacterial activity of the biocontrol agent, Stenotrophomonas maltophilia (PD4560), against Ralstonia solanacearum invitro and invivo. Optimization of conditions that favour these mechanisms was the second target of this study. Proteolytic activity of Sten.maltophilia (PD 4560), was tested on skimmed milk medium. The biocontrol agent was able to produce an alkaline serine protease enzyme with a molecular weight of 40 KDa as determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis analyses. Spraying of salicylic acid (SA) led to an increase in the efficacy of Sten.maltophilia in controlling the Ralstonia potato wilt while spraying of ammonium sulphate (AmS) did not affect the biocontrol efficacy. The efficacy was correlated with the expression of protease enzyme genes; Prt genes (mainly PrtP and Prt4) and PR genes (mainly PR-1 and PRQ) as evaluated using real-time polymerase chain reaction analysis. The biocontrol activity of Sten.maltophilia can be attributed to the direct mechanism alkaline serine proteolytic enzyme production and through induction of host systemic acquired resistance as indirect mechanism. Tuber bulking was the most suitable physiological growth stage to apply either SA or the biocontrol agent. Both SA and peat-moss as an organic carrier enhanced the antibacterial efficiency of the biocontrol agent. Application of Sten.maltophilia is more suitable under alkaline soil conditions.

Effects of Paste Composition and Sintering Process on Performance of Silver Paste for Silicon Solar Cells

In order to study the effects of composition ratio of silver paste and the sintering process on the properties of the silver film after sintering, the effects of different ratios of silver powders, glass powders and organic carrier in silver paste and different sintering temperatures and sintering time on the adhesion force and square resistance of the silver film were studied. The morphology of the sintered silver film was observed by SEM. The results showed that the silver film sintered at 760°C for 6 seconds had better properties after sintering when the ratio of silver powders, glass powders and organic carrier in silver paste was 80:5:15 and the silver powders was composed of spherical silver powders and flake silver powders at the ratio of 94:6. The adhesion force and square resistance of the silver film were 8.25 N and 3.47mΩ /□, respectively.

Tailoring the viscoelastic properties of injectable biocomposites: A spectroscopic assessment of the interactions between organic carriers and bioactive glass particles

Injectable bioglass (BG) pastes were produced using a melt-quenched glass based on CaO–MgO–SiO2–Na2O–P2O5–CaF2 and two organic carriers, namely polyethylene glycol (PEG) and glycerol (Gly). The interactions between the organic carriers and the surface of the BG particles were assessed by spectroscopic methods (Fourier Transform Infrared, Raman, as well as 29Si and 13C solid-state NMR spectroscopy) in order to understand their effects on the viscoelastic properties of the biocomposites. While pure physical interactions were detected between PEG and the surface of the BG particles, chemical bonding was observed between glycerol and BG, enhancing the network cross-linking degree. Accordingly, the BG network of Gly-BG pastes was more condensed (higher fraction of Q [3] units detected by Raman spectroscopy) in comparison to that of PEG-BG and bare BG. Such chemical interactions between the organic carrier and BG were shown to negatively affect the viscoelastic behaviour of the resulting pastes. Thus, the PEG-based biocomposite exhibited improved flowability in comparison to its analogous Gly-BG biocomposite.