Polymer Electret Improves the Performance of the Oxygen-Doped Organic Field-Effect Transistors

Chemical doping is widely used in the electronic devices. In p-type semiconductor thin films, oxygen doping fills the hole traps and increases hole concentrations, improving the performance of the organic field-effect transistors (OFETs). Due to the low ionization potential for p-type semiconductors, the superfluous holes induced by the oxygen doping degrades the OFETs off-state leakage performance. On the other hand, for p-type semiconductors with high ionization potential (up to 5.5-6.0 eV), the limited oxidation of oxygen is hard to achieve satisfactory doping concentrations to fill the trap states. This refers to the well-known intrinsic incompatibility between the oxygen doping and high-performance OFETs. Herein, a novel strategy is introduced to overcome the incompatibility and achieve high-performance OFETs by using the structural polymer electret. That is, moderate hole concentrations induced by low-pressure (30 Pa) oxygen plasma fill the hole traps within semiconductor. And the built-in field resulted from polymer electret accumulates the holes inside semiconductor near the semiconductor/electret interface, thus improving the OFETs performance. Using a model organic semiconductor with high ionization potential-2,7-didodecyl[1]benzothieno [3,2-b][1]benzothiophene (C12-BTBT) as an example, the high-performance OFETs with field-effect mobility (μFET) of 3.5 cm 2 V -1 s -1 , subthreshold-swing (SS) of 110 mV decade -1 , on-off ratio of 10 4 , and widely-tunable threshold voltage (V t ) are realized at a low voltage below 2 V in the open air

Crystallization Control of N,N′-Dioctyl Perylene Diimide by Amphiphilic Block Copolymers Containing poly(3-Hexylthiophene) and Polyethylene Glycol

The preparation of micron- to nanometer-sized functional materials with well-defined shapes and packing is a key process to their applications. There are many ways to control the crystal growth of organic semiconductors. Adding polymer additives has been proven a robust strategy to optimize semiconductor crystal structure and the corresponding optoelectronic properties. We have found that poly(3-hexylthiophene) (P3HT) can effectively regulate the crystallization behavior of N,N′-dioctyl perylene diimide (C8PDI). In this study, we combined P3HT and polyethylene glycol (PEG) to amphiphilic block copolymers and studied the crystallization modification effect of these block copolymers. It is found that the crystallization modification effect of the block copolymers is retained and gradually enhanced with P3HT content. The length of C8PDI crystals were well controlled from 2 to 0.4 μm, and the width from 210 to 35 nm. On the other hand, due to the water solubility of PEG block, crystalline PEG-b-P3HT/C8PDI micelles in water were successfully prepared, and this water phase colloid could be stable for more than 2 weeks, which provides a new way to prepare pollution-free aqueous organic semiconductor inks for printing electronic devices

Effects of Clinically Relevant MPL Mutations in the Transmembrane Domain Revealed at the Atomic Level through Computational Modeling

BACKGROUND: Mutations in the thrombopoietin receptor (MPL) may activate relevant pathways and lead to chronic myeloproliferative neoplasms (MPNs). The mechanisms of MPL activation remain elusive because of a lack of experimental structures. Modern computational biology techniques were utilized to explore the mechanisms of MPL protein activation due to various mutations. RESULTS: Transmembrane (TM) domain predictions, homology modeling, ab initio protein structure prediction, and molecular dynamics (MD) simulations were used to build structural dynamic models of wild-type and four clinically observed mutants of MPL. The simulation results suggest that S505 and W515 are important in keeping the TM domain in its correct position within the membrane. Mutations at either of these two positions cause movement of the TM domain, altering the conformation of the nearby intracellular domain in unexpected ways, and may cause the unwanted constitutive activation of MPL's kinase partner, JAK2. CONCLUSIONS: Our findings represent the first full-scale molecular dynamics simulations of the wild-type and clinically observed mutants of the MPL protein, a critical element of the MPL-JAK2-STAT signaling pathway. In contrast to usual explanations for the activation mechanism that are based on the relative translational movement between rigid domains of MPL, our results suggest that mutations within the TM region could result in conformational changes including tilt and rotation (azimuthal) angles along the membrane axis. Such changes may significantly alter the conformation of the adjacent and intrinsically flexible intracellular domain. Hence, caution should be exercised when interpreting experimental evidence based on rigid models of cytokine receptors or similar systems

Study on Characteristics of Particle Dynamics with Coarse Particles in Vertical and Inclined Pipeline

Abstract The pipeline hydraulic transport is an important component of the deep-sea mineral resources. The characteristics of particle dynamics with coarse particles is investigated by using the CFD-DEM method in the vertical and inclined pipeline. The normal pipeline and abnormal pipeline mentioned in this paper refer to vertical pipeline and inclined pipeline, respectively. The particles of the normal pipeline mainly move in the middle of the pipeline, while the particles mainly concentrate on the pipeline wall in the abnormal pipeline. The velocity difference of the abnormal pipeline between liquid and particle is much greater, which can be prone to cause particle aggregation. Finally, the pipeline to be blocked can be easy to be caused by the particle aggregation in the wall of abnormal pipeline. An appropriate increase in liquid velocity can improve the phenomenon

Flow regimes and characteristics of dense particulate flows with coarse particles in inclined pipe

This paper presents a numerical simulation for dense particulate flows with coarse particles in inclined pipe to identify different flow regimes by means of computational fluid dynamics-discrete element method. The drag, gravitational, pressure gradient and virtual mass forces on particles, as well as the effect of particle-particle collisions are considered. Two flow regimes and their transitions are observed and described. The influence of Stokes number St, Froude number Fr, inclination angle fl, etc., on critical flow regimes is analyzed to identify the dependence of flow regimes on these parameters. A new diagram for recognizing regime transition is given. The temporal variations of flow fields are also analyzed to illustrate propagating of kinematic waves. The wave velocity increases with Fr, fl, and particle concentration increasing. Two dimensionless numbers, collision stress and fluid-particle interaction stress, are defined to explain the regime transition mechanism. The maximum pressure drop occurs at approximately fl = 60 & DEG;

Facile Graphene Oxide Modification Method via Hydroxyl-yne Click Reaction for Ultrasensitive and Ultrawide Monitoring Pressure Sensors.

Enhancing the durability and functionality of existing materials through sustainable pathways and appropriate structural design represents a time- and cost-effective strategy for the development of advanced wearable devices. Herein, a facile graphene oxide (GO) modification method via the hydroxyl-yne click reaction is present for the first time. By the click coupling between propiolate esters and hydroxyl groups on GO under mild conditions, various functional molecules are successfully grafted onto the GO. The modified GO is characterized by FTIR, XRD, TGA, XPS, and contact angle, proving significantly improved dispersibility in various solvents. Besides the high efficiency, high selectivity, and mild reaction conditions, this method is highly practical and accessible, avoiding the need for prefunctionalizations, metals, or toxic reagents. Subsequently, a rGO-PDMS sponge-based piezoresistive sensor developed by modified GO-P2 as the sensitive material exhibits impressive performance: high sensitivity (335 kPa-1, 0.8-150 kPa), wide linear range (>500 kPa), low detection limit (0.8 kPa), and long-lasting durability (>5000 cycles). Various practical applications have been demonstrated, including body joint movement recognition and real-time monitoring of subtle movements. These results prove the practicality of the methodology and make the rGO-PDMS sponge-based pressure sensor a real candidate for a wide array of wearable applications

Kinematic waves and collision effects in dense fluid-particle flow during hydraulic conveying

The effects of fluid-particle and particle-particle interactions on the kinematic waves and particle dynamics in a vertical pipe with continuous upward fluid flow are investigated. The unresolved computational fluid dynamics-discrete element method, in which fluid flow field is modeled using large eddy simulation with dynamic Smagorinsky model for the eddy viscosity, is used to simulate the conveying process for particle Reynolds numbers within 8000 and 40000. The results imply that it can show kinematic waves and determine wave velocity based on the wave frequency and wave number relationships, which is also found to closely agree with the theory of kinematic waves based on the Richardson-Zaki relation. One feature is that the kinematic wave velocity in hydraulic conveying manifests itself in relation to the upward fluid velocity. In addition, two different flow regimes are found in the simulation. For relative low particle Reynolds numbers (8000< Re-p <16000), the collision and hydrodynamic effects are equally important (regime 1). As the particle Reynolds number increases, the relative significance of collision effects increases. At Re-p=16000, the collision effects go beyond the hydrodynamic effects, leading to the flow regime transition (regime 2). The increase of the collision effects also makes the particles uniformly distributed

Effect of poly-β-hydroxybutyrate on growth, enzyme activity and intestinal microbial community of Chinese mitten crab, Eriocheir sinensis (Milne-Edwards) juveniles

Poly-beta-hydroxybutyrate (PHB) is microbial carbon and energy storage polymer, which can be degraded into water-soluble beta-hydroxybutyric acid in the gastrointestinal tract of aquatic animals. A 60-day culture experiment was performed using Chinese mitten crab, Eriocheir sinensis (Milne-Edwards) juveniles with an average initial body weight of 0.74 +/- 0.06 g which were fed a diet supplemented with 0%, 0.5%, 1%, 3% or 5% PHB. A PHB dietary supplementation of 1% and 3% significantly improved the body weight gain, moulting frequency and concomitantly reduced 2nd-3rd moulting intervals of the crabs (P < 0.05). The dietary PHB level positively related to hepatopan-creatic pepsin, trypsin and lipase activity (P < 0.05). Increasing the dietary PHB also improved total superoxide dismutase activity, but reduced alkaline phosphatase and acid phosphatase activity in the serum of hemolymph (P < 0.05). A 16S rRNA gene analysis by denaturing gradient gel electrophoresis indicated that PHB supplementation led to a significantly higher range-weighted richness, diversity and evenness of the gut bacterial community when dosed at 3% in the feed. The beneficial effects of PHB are discussed in terms of immune defense, metabolism and gut microbiota of the crabs

Genome-Wide Analysis of Multiple Organellar RNA Editing Factor Family in Poplar Reveals Evolution and Roles in Drought Stress

Poplar (Populus) is one of the most important woody plants worldwide. Drought, a primary abiotic stress, seriously affects poplar growth and development. Multiple organellar RNA editing factor (MORF) genes&#8212;pivotal factors in the RNA editosome in Arabidopsis thaliana&#8212;are indispensable for the regulation of various physiological processes, including organelle C-to-U RNA editing and plasmid development, as well as in the response to stresses. Although the poplar genome sequence has been released, little is known about MORF genes in poplar, especially those involved in the response to drought stress at the genome-wide level. In this study, we identified nine MORF genes in the Populus genome. Based on the structural features of MORF proteins and the topology of the phylogenetic tree, the P. trichocarpa (Ptr) MORF family members were classified into six groups (Groups I&#8211;VI). A microsynteny analysis indicated that two (22.2%) PtrMORF genes were tandemly duplicated and seven genes (77.8%) were segmentally duplicated. Based on the dN/dS ratios, purifying selection likely played a major role in the evolution of this family and contributed to functional divergence among PtrMORF genes. Moreover, analysis of qRT-PCR data revealed that PtrMORFs exhibited tissue- and treatment-specific expression patterns. PtrMORF genes in all group were involved in the stress response. These results provide a solid foundation for further analyses of the functions and molecular evolution of MORF genes in poplar, and, in particular, for improving the drought resistance of poplar by genetics manipulation

Facile Graphene Oxide Modification Method via Hydroxyl-yne Click Reaction for Ultrasensitive and Ultrawide Monitoring Pressure Sensors

Enhancing the durability and functionality of existing materials through sustainable pathways and appropriate structural design represents a time- and cost-effective strategy for the development of advanced wearable devices. Herein, a facile graphene oxide (GO) modification method via the hydroxyl-yne click reaction is present for the first time. By the click coupling between propiolate esters and hydroxyl groups on GO under mild conditions, various functional molecules are successfully grafted onto the GO. The modified GO is characterized by FTIR, XRD, TGA, XPS, and contact angle, proving significantly improved dispersibility in various solvents. Besides the high efficiency, high selectivity, and mild reaction conditions, this method is highly practical and accessible, avoiding the need for prefunctionalizations, metals, or toxic reagents. Subsequently, a rGO-PDMS sponge-based piezoresistive sensor developed by modified GO-P2 as the sensitive material exhibits impressive performance: high sensitivity (335 kPa–1, 0.8–150 kPa), wide linear range (>500 kPa), low detection limit (0.8 kPa), and long-lasting durability (>5000 cycles). Various practical applications have been demonstrated, including body joint movement recognition and real-time monitoring of subtle movements. These results prove the practicality of the methodology and make the rGO-PDMS sponge-based pressure sensor a real candidate for a wide array of wearable applications