This paper proposes an improved ant colony algorithm to achieve efficient searching capabilities of path planning in complicated maps for mobile robot. The improved ant colony algorithm uses the characteristics of A * algorithm and MAX-MIN Ant system. Firstly, the grid environment model is constructed. The evaluation function of A * algorithm and the bending suppression operator are introduced to improve the heuristic information of the Ant colony algorithm, which can accelerate the convergence speed and increase the smoothness of the global path. Secondly, the retraction mechanism is introduced to solve the deadlock problem. Then the MAX-MIN ant system is transformed into local diffusion pheromone and only the best solution from iteration trials can be added to pheromone update. And, strengths of the pheromone trails are effectively limited for avoiding premature convergence of search. This gives an effective improvement and high performance to ACO in complex tunnel, trough and baffle maps and gives a better result as compare to traditional versions of ACO. The simulation results show that the improved ant colony algorithm is more effective and faster.

Intensified research interests are posed with the thionucleobase 4-thiouracil (4-TU), due to its important biological function as site-specific photoprobe to detect RNA structures and nucleic acid-nucleic acid contacts. By means of time-resolved IR spectroscopy and density functional theory (DFT) studies, we have examined the unique photophysical and photochemical properties of 4-TU. It is shown that 4-TU absorbs UVA light and results in the triplet formation with a high quantum yield (0.9). Under N2-saturated anaerobic conditions, the reactive triplet undergoes mainly cross-linking, leading to the (5-4)/(6-4) pyrimidine-pyrimidone product. In the presence of O2 under aerobic conditions, the triplet 4-TU acts as an energy donor to produce singlet oxygen (1)O2 by triplet-triplet energy transfer. The highly reactive oxygen species (1)O2 then reacts readily with 4-TU, leading to the products of uracil (U) with a yield of 0.2 and uracil-6-sulfonate (U(SO3)) that is fluorescent at ~390 nm. The product formation pathways and product distribution are well rationalized by the joint B3LYP/6-311+G(d,p) calculations. From dynamics and mechanistic point of views, these results enable a further understanding for 4-TU acting as reactive precursors for photochemical reactions relevant to (1)O2, which has profound implications for photo cross-linking, DNA photodamage, as well as photodynamic therapy studies.

Molecular doping of organic electronics has shown promise to sensitively modulate important device metrics. One critical challenge is the disruption of structure order upon doping of highly crystalline organic semiconductors, which significantly reduces the charge carrier mobility. This paper demonstrates a new method to achieve large modulation of charge carrier mobility via channel doping without disrupting the molecular ordering. Central to the method is the introduction of nanopores into the organic semiconductor thin films via a simple and robust templated meniscus-guided coating method. Using this method, the charge carrier mobility of C -benzothieno[3,2-b]benzothiophene transistors is boosted by almost sevenfold. This paper further demonstrates enhanced electron transport by close to an order of magnitude in a diketopyrrolopyrrole-based donor-acceptor polymer. Combining spectroscopic measurements, density functional theory calculations, and electrical characterizations, the doping mechanism is identified as partial-charge-transfer induced trap filling. The nanopores serve to enhance the dopant/organic semiconductor charge transfer reaction by exposing the π-electrons to the pore wall.

Lightweight and low-cost flexible thermoelectric (TE) materials improve the heat-to-electricity conversion efficiency compared to rigid materials by minimizing the heat loss between TE devices and heat sources in waste heat recovery. Multi-walled carbon nanotube (MWCNT) has excellent mechanical and electrical properties. However, the TE power factor (PF) of MWCNTs is much lower than single/double-walled carbon nanotube (S/DWCNT), which is often lower than 40 µW m −1 -K −2 . Herein an effective way to achieve high PFs of ≈1800 µW m −1 -K −2 for p-type and ≈1000 µW m −1 -K −2 for n-type in flexible MWCNT films is reported. The high power factor is achieved by taking advantage of the anisotropic electrical conductivity and isotropic Seebeck coefficient feature of 1D CNTs as well as the following doping and cold-pressing to improve the electrical conductivity of MWCNT films. The PF values are comparable to that of state-of-the-art S/DWCNT films and most inorganic TE materials. A Lego-like TE generator (TEG) with an assembling structure is fabricated to show the heat-to-electricity ability of the materials, which exhibits the highest areal output power of ≈27 W m −2 among CNT-based flexible TEGs. This method may be extended to other 1D-material based composites to boost the development of high PF flexible TE materials.

Chlorosilanes are versatile reagents in organic synthesis and material science.Amild pathway is nowreported for the quantitative conversion of hydrosilanes to silyl chlorides under visible-light irradiation using neutral eosin Ya s ah ydrogen-atom-transfer photocatalyst and dichloromethane as ac hlorinating agent. Stepwise chlorination of di-and trihydrosilanes was achieved in ah ighly selective fashion assisted by continuous-flowm icro-tubing reactors.T he ability to access silyl radicals using photocatalytic SiÀHa ctivation promoted by eosin Yoffers new perspectives for the synthesis of valuable silicon reagents in aconvenient and green manner.

The solar galactic neighbourhood contains a number of young co-moving associations of stars (so-called 'young moving groups') with ages of ∼10-150 Myr, which are prime targets for a range of scientific studies, including direct imaging planet searches. The late-type stellar population of such groups still remain in their pre-main sequence phase, and are thus well suited for purposes such as isochronal dating. Close binaries are particularly useful in this regard, since they allow for a model-independent dynamical mass determination. Here we present a dedicated effort to identify new close binaries in nearby young moving groups, through high-resolution imaging with the AstraLux Sur Lucky Imaging camera. We surveyed 181 targets, resulting in the detection of 61 companions or candidates, of which 38 are new discoveries. An interesting example of such a case is 2MASS J00302572-6236015 AB, which is a high-probability member of the Tucana-Horologium moving group, and has an estimated orbital period of less than 10 years. Among the previously known objects is a serendipitous detection of the deuterium burning boundary circumbinary companion 2MASS J01033563-5515561 (AB)b in the z ′ -band, thereby extending the spectral coverage for this object down to near-visible wavelengths.

Molecular orientation plays a critical role in controlling carrier transport in organic semiconductors (OSCs). However, this aspect has not been explored for surface doping of OSC thin films. The challenge lies in lack of methods to precisely modulate relative molecular orientation between the dopant and the OSC host. Here, the impact of molecular orientation on dopant–host electronic interactions by large modulation of conjugated polymer orientation via solution coating is reported. Combining synchrotron‐radiation X‐ray measurements with spectroscopic and electrical characterizations, a quantitative correlation between doping‐enhanced charge carrier mobility and the Herman's orientation parameter is presented. This direct correlation can be attributed to enhanced charge‐transfer interactions at host/dopant interface with increasing face‐on orientation of the polymer. These results demonstrate that the surface doping effect can be fundamentally manipulated by controlling the molecular orientation of the OSC layer, enabling optimization of carrier transport.

Aerogels have been attracting wide attentions in flexible/wearable electronics because of their light weight, excellent flexibility, and electrical conductivity. However, multifunctional aerogel-based flexible/wearable electronics for human physiological/motion monitoring, and energy harvest/supply for mobile electronics, have been seldom reported yet. In this study, a kind of hybrid aerogel (GO/CNT HA) based on graphene oxide (GO) and carboxylated multiwalled carbon nanotubes (CMWCNTs) is prepared which can not only used as piezoresistive sensors for human motion and physiological signal detections, but also as high performance triboelectric nanogenerator (TENG) coupled with both solid-solid and gas-solid contact electrifications (CE). The repeatedly loading-unloading tests with 20 000 cycles exhibit its high and ultrastable piezoresistive sensor performances. Moreover, when the obtained aerogel is used as the electrode of a TENG, high electric output performance is produced due to the synergistic effect of solid-solid, and gas-solid interface CEs (3D electrification: solid-solid interface CE between the two solid electrification layers; gas-solid interface CE between the inner surface of GO/CNT HA and the air filled in the aerogel pores). This kind of aerogel promises good applications for human physiological/motion monitoring and energy harvest/supply in flexible/wearable electronics such as piezoresistive sensors and flexible TENG.