Stretchable semiconducting polymers have been developed as a key component to enable skin-like wearable electronics, but their electrical performance must be improved to enable more advanced ...functionalities. Here, we report a solution processing approach that can achieve multi-scale ordering and alignment of conjugated polymers in stretchable semiconductors to substantially improve their charge carrier mobility. Using solution shearing with a patterned microtrench coating blade, macroscale alignment of conjugated-polymer nanostructures was achieved along the charge transport direction. In conjunction, the nanoscale spatial confinement aligns chain conformation and promotes short-range π-π ordering, substantially reducing the energetic barrier for charge carrier transport. As a result, the mobilities of stretchable conjugated-polymer films have been enhanced up to threefold and maintained under a strain up to 100%. This method may also serve as the basis for large-area manufacturing of stretchable semiconducting films, as demonstrated by the roll-to-roll coating of metre-scale films.
A
bstract
We obtain the complete operator bases at mass dimensions 5, 6, 7, 8, 9 for the low energy effective field theory (LEFT), which parametrize various physics effects between the QCD scale and ...the electroweak scale. The independence of the operator basis regarding the equation of motion, integration by parts and flavor relations, is guaranteed by our algorithm 1, 2, whose validity for the LEFT with massive fermions involved is proved by a generalization of the amplitude-operator correspondence. At dimension 8 and 9, we list the 35058 (756) and 704584 (3686) operators for three (one) generations of fermions categorized by their baryon and lepton number violations (∆
B
, ∆
L
), as these operators are of most phenomenological relevance.
The evolution of increased competitive ability (EICA) hypothesis and the novel weapons hypothesis (NWH) are two non-mutually exclusive mechanisms for exotic plant invasions, but few studies have ...simultaneously tested these hypotheses. Here we aimed to integrate them in the context of Chromolaena odorata invasion.
We conducted two common garden experiments in order to test the EICA hypothesis, and two laboratory experiments in order to test the NWH.
In common conditions, C. odorata plants from the nonnative range were better competitors but not larger than plants from the native range, either with or without the experimental manipulation of consumers. Chromolaena odorata plants from the nonnative range were more poorly defended against aboveground herbivores but better defended against soilborne enemies. Chromolaena odorata plants from the nonnative range produced more odoratin (Eupatorium) (a unique compound of C. odorata with both allelopathic and defensive activities) and elicited stronger allelopathic effects on species native to China, the nonnative range of the invader, than on natives of Mexico, the native range of the invader.
Our results suggest that invasive plants may evolve increased competitive ability after being introduced by increasing the production of novel allelochemicals, potentially in response to naïve competitors and new enemy regimes.
The light-harvesting core antenna (LH1) and the reaction centre (RC) of purple photosynthetic bacteria form a supramolecular complex (LH1-RC) to use sunlight energy in a highly efficient manner. Here ...we report the first near-atomic structure, to our knowledge, of a LH1-RC complex, namely that of a Ca(2+)-bound complex from Thermochromatium tepidum, which reveals detailed information on the arrangement and interactions of the protein subunits and the cofactors. The RC is surrounded by 16 heterodimers of the LH1 αβ-subunit that form a completely closed structure. The Ca(2+) ions are located at the periplasmic side of LH1. Thirty-two bacteriochlorophyll and 16 spirilloxanthin molecules in the LH1 ring form an elliptical assembly. The geometries of the pigment assembly involved in the absorption characteristics of the bacteriochlorophyll in LH1 and excitation energy transfer among the pigments are reported. In addition, possible ubiquinone channels in the closed LH1 complex are proposed based on the atomic structure.
Celotno besedilo
Dostopno za:
DOBA, IJS, IZUM, KILJ, KISLJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
With the rapid development of virtual technology and data acquisition technology, digital twin (DT) technology was proposed and gradually become one of the key research directions of intelligent ...manufacturing. However, the research of DT for product life cycle management is still in the theoretical stage, the application framework and application methods are not clear, and the lack of referable application cases is also a problem. In this paper, the related research and application of DT technology are systematically studied. Then the concept and characteristics of DT are interpreted from both broad sense and narrow sense. On this basis, an application framework of DT for product lifecycle management is proposed. In physical space, the total-elements information perception technology of production is discussed in detail. In the information processing layer, three main function modules, including data storage, data processing and data mapping, are constructed. In virtual space, this paper describes the implementation process of full parametric virtual modeling and the construction idea for DT application subsystems. At last, a DT case of a welding production line is built and studied. Meanwhile, the implementation scheme, application process and effect of this case are detail described to provide reference for enterprises.
Planar backbone, locked conformation, and low lowest unoccupied molecular orbital level provide polymer F4BDOPV‐2T with ultrahigh electron mobilities of up to 14.9 cm2 V−1 s−1 and good air stability. ...It is found that the nonlinear transfer curves can be tuned to near‐ideal ones by changing fabrication conditions, indicating that film morphology largely contributes to the nonlinear transfer curves in high‐mobility conjugated polymers.
The homojunction of oxygen/metal vacancies and its interfacial n–p effect on the physiochemical properties are rarely reported. Interfacial n–p homojunctions of TiO2 are fabricated by directly ...decorating interfacial p‐type titanium‐defected TiO2 around n‐type oxygen‐defected TiO2 nanocrystals in amorphous–anatase homogeneous nanostructures. Experimental measurements and theoretical calculations on the cell lattice parameters show that the homojunction of oxygen and titanium vacancies changes the charge density of TiO2; a strong EPR signal caused by oxygen vacancies and an unreported strong titanium vacancies signal of 2D 1H TQ‐SQ MAS NMR are present. Amorphous–anatase TiO2 shows significant performance regarding the photogeneration current, photocatalysis, and energy storage, owing to interfacial n‐type to p‐type conductivity with high charge mobility and less structural confinement of amorphous clusters. A new “homojunction of oxygen and titanium vacancies” concept, characteristics, and mechanism are proposed at an atomic‐/nanoscale to clarify the generation of oxygen vacancies and titanium vacancies as well as the interface electron transfer.
The homojunction of oxygen and titanium vacancies developed in the amorphous–anatase interface of nanostructured TiO2 results in a unique n–p electronic transmission, which is mostly preferred to the mobility of electronic charge carriers. It also contributes to significant performance regarding photogeneration current, photocatalysis, and energy storage.
Carbon nanotube (CNT) thin-film transistor (TFT) is a promising candidate for flexible and wearable electronics. However, it usually suffers from low semiconducting tube purity, low device yield, and ...the mismatch between p- and n-type TFTs. Here, we report low-voltage and high-performance digital and analog CNT TFT circuits based on high-yield (19.9%) and ultrahigh purity (99.997%) polymer-sorted semiconducting CNTs. Using high-uniformity deposition and pseudo-CMOS design, we demonstrated CNT TFTs with good uniformity and high performance at low operation voltage of 3 V. We tested forty-four 2-µm channel 5-stage ring oscillators on the same flexible substrate (1,056 TFTs). All worked as expected with gate delays of 42.7 ± 13.1 ns. With these high-performance TFTs, we demonstrated 8-stage shift registers running at 50 kHz and the first tunable-gain amplifier with 1,000 gain at 20 kHz. These results show great potentials of using solution-processed CNT TFTs for large-scale flexible electronics.
Urban computing is a process of acquisition, integration and analysis of big and heterogeneous data generated by a diver- sity of sources in urban spaces, such as sensors, devices, ve- hicles, ...buildings and humans, to tackle the major issues that cities face, e.g., air pollution, energy consumption and traffic congestion. Urban computing connects unobtrusive and ubiq- uitous sensing technologies, advanced data management and analytics models, and novel visualization methods.
Forecasting the flow of crowds is of great importance to traffic management and public safety, and very challenging as it is affected by many complex factors, including spatial dependencies (nearby ...and distant), temporal dependencies (closeness, period, trend), and external conditions (e.g. weather and events). We propose a deep-learning-based approach, called ST-ResNet, to collectively forecast two types of crowd flows (i.e. inflow and outflow) in each and every region of a city. We design an end-to-end structure of ST-ResNet based on unique properties of spatio-temporal data. More specifically, we employ the residual neural network framework to model the temporal closeness, period, and trend properties of crowd traffic. For each property, we design a branch of residual convolutional units, each of which models the spatial properties of crowd traffic. ST-ResNet learns to dynamically aggregate the output of the three residual neural networks based on data, assigning different weights to different branches and regions. The aggregation is further combined with external factors, such as weather and day of the week, to predict the final traffic of crowds in each and every region. We have developed a real-time system based on Microsoft Azure Cloud, called UrbanFlow, providing the crowd flow monitoring and forecasting in Guiyang City of China. In addition, we present an extensive experimental evaluation using two types of crowd flows in Beijing and New York City (NYC), where ST-ResNet outperforms nine well-known baselines.
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