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The application of organic–inorganic perovskites has recently attracted increasing interest due to their excellent optoelectronic properties. As an emerging semiconductor, the doping capability and...

Steels with sub-micrometre grain sizes usually possess high toughness and strength, which makes them promising for lightweighting technologies and energy-saving strategies. So far, the industrial fabrication of ultrafine-grained (UFG) alloys, which generally relies on the manipulation of diffusional phase transformation, has been limited to steels with austenite-to-ferrite transformation1–3. Moreover, the limited work hardening and uniform elongation of these UFG steels1,4,5 hinder their widespread application. Here we report the facile mass production of UFG structures in a typical Fe–22Mn–0.6C twinning-induced plasticity steel by minor Cu alloying and manipulation of the recrystallization process through the intragranular nanoprecipitation (within 30 seconds) of a coherent disordered Cu-rich phase. The rapid and copious nanoprecipitation not only prevents the growth of the freshly recrystallized sub-micrometre grains but also enhances the thermal stability of the obtained UFG structure through the Zener pinning mechanism6. Moreover, owing to their full coherency and disordered nature, the precipitates exhibit weak interactions with dislocations under loading. This approach enables the preparation of a fully recrystallized UFG structure with a grain size of 800 ± 400 nanometres without the introduction of detrimental lattice defects such as brittle particles and segregated boundaries. Compared with the steel to which no Cu was added, the yield strength of the UFG structure was doubled to around 710 megapascals, with a uniform ductility of 45 per cent and a tensile strength of around 2,000 megapascals. This grain-refinement concept should be extendable to other alloy systems, and the manufacturing processes can be readily applied to existing industrial production lines. Bulk ultrafine-grained steel is prepared by an approach that involves the rapid production of coherent, disordered nanoprecipitates, which restrict grain growth but do not interfere with twinning or dislocation motion, resulting in high strength and ductility.

Perovskite materials have displayed remarkable performance when used in photovoltaic devices. In comparison, research on their application in thin-film transistors (TFTs) has been developing slowly...

A spinodal decomposition is often carried out in the austenite-ferrite duplex stainless steel Fe20Cr9Ni during long-term service at a temperature in the range from 280 to 320°C, resulting in a decrease of pitting corrosion resistance. Fe-rich α phase rather than G-phase has been suggested as the major reason for the deterioration in pitting corrosion resistance of the thermally-aged steel. Here, we found that ∼76.8% of the decline in pitting resistance for the duplex stainless steel Fe20Cr9Ni was attributed to G-phase, and ∼23.2% to Fe-rich α phase after the spinodal decomposition. In this study, a suitable thermal aging treatment was introduced to obtain a larger size of the G-phase and to study the role of the phase in the corrosion process. Through immersing thermally-aged TEM specimen treated at 475°C for 3000 h in NaCl solution, the preferential position of corrosion pits formed in the ferrite was obtained. The composition changes and strain field distribution around the G-phase were analyzed by TEM-EDS, 3DAPT and GPA techniques. We further found that, although the concentration difference of Cr element between α and α’ phases was as high as 60 at.%, corrosion pits were initiated at the interface between the G-phase and the ferrite matrix rather than in the Fe-rich α phase, indicating that the Cr-depleted theory could not explain the aforesaid phenomenon. The strain energy at the interface between the G-phase and the ferrite matrix was found to be the largest. The atoms at the interface have higher energy than in the intracrystalline, and thus easily react with Cl− ions in the solution to form pits finally.

Two organic–inorganic hybrids, [3-H2DPNDI][ZnCl4]·0.5H2O (1) and [4-H2DPNDI][ZnCl4]·0.5H2O (2) (3-H2DPNDI2+ = protonated N,N-di(3-pyridyl)-1,4,5,8-naphthalene diimide, 4-H2DPNDI2+ = protonated N,N-...

In this work, BCN-TiO2(A+R) heterojunctions were constructed via a simple one-step calcination method as efficient photocatalysts for H2 evolution. Simultaneously, an anatase/rutile phase-junction was also obtained due to the crystalline phase transformation that occurred during high-temperature calcination. The unique heterojunction and phase-junction lead to the formation of an intimate interface and large contact area between two semiconductors and extended the visible-light absorption range. Therefore, BCN-TiO2(A+R) heterojunctions with a mixed anatase and rutile phase exhibit enhanced photocarrier separation efficiency, realizing an eleven-fold increase in the electron lifetime compared to that of pure TiO2 and yielding a remarkable visible-light-driven H2 evolution rate nearly 7.5 and 12.2 times higher than that of TiO2(A+R) and pure BCN, respectively. This work provides a new strategy for designing efficient water-splitting photocatalysts with highly efficient charge separation and transfer.

Transparent polycrystalline p-channel copper bromide (CuBr) thin-film transistors (TFTs) are fabricated using a simple one-step spin coating at room temperature. Optimized CuBr TFTs operate in depletion mode with an on-voltage of 35 V and exhibit a hole mobility of 0.15 cm $^{2}\,\,\text{V}^{-1}\,\,\text{s}^{-1}$ , high ON/OFF current ratio ${\sim }10^{4}$ and cycling bias sweep/air stabilities. The performance is superior to that of most solution-processed p-type oxide TFTs, highlighting CuBr as a promising p-type candidate for next-generation printable transparent electronics.

Since hole transport materials (HTMs) play a significant role in enhancing the power conversion efficiency (PCE) and stability of perovskite solar cells (PSCs), which are the key factors for their commercialization, an effective design strategy is necessary for the potential HTMs in the current emerging field of PSCs. Here, we present a new class of HTM with pyridine as a central core with an extended π-conjugated molecular structure with electron-donating blocks. We have systematically investigated its photophysical, thermal, electrochemical, and charge transport properties and found that 4,4′-(5,5′-(pyridine-2,6-diylbis(4,1-phenylene))bis(thiophene-5,2-diyl))bis(N,N-bis(4-methoxyphenyl)aniline) (PyThTPA) is a potential HTM candidate for making PSCs. The PyThTPA HTM-based PSC attained an average PCE of 16.57% with outstanding long-term durability of over 720 hrs with minimal reduction of its initial PCE and negligible hysteresis. This PSC performance was 34% higher than that of the state-of-the-art HTM, Spiro-OMeTAD with tris(pentafluorophenyl)borane (BCF). We speculate that the Lewis acid-base adduct (LABA) formation of pyridine in the HTM and BCF interacted with methylammonium lead iodide (MAPbI3), resulting in the MAPbI3/HTM interface becoming more selective for holes. This also enhanced the film uniformity and afforded a smoother morphology with improved hydrophobicity that further increased the long-term durability. Furthermore, the mobility and conductivity were increased for PyThTPA with BCF. To the best of our knowledge, this is the first report of pyridine being incorporated into the HTM with continuous π-conjugation and with a high performance of nearly 17%. Overall, we believe that this approach will be an effective design strategy capable of enhancing the performance of PSCs with less hysteresis and improved long-term durability.

Although organic–inorganic halide perovskites continue to generate considerable interest due to great potentials for various optoelectronic devices, there are some critical obstacles to practical applications, including lead toxicity, relatively low field-effect mobility, and strong hysteresis during operation. This paper proposes a universal approach to significantly improve mobility and operational stability with reduced dual-sweep hysteresis for perovskite-based thin film transistors (TFTs) by coupling low-dimensional lead-free perovskite material (C6H5C2H4NH3)2SnI4 (hereafter abbreviated as (PEA)2SnI4) with embedded conjugated polymer wrapped semiconducting carbon nanotubes (semi-CNTs). In (PEA)2SnI4/semi-CNT hybrid TFTs, semi-CNTs can provide highway-like transport paths, enabling smoother carrier transport with less trapping and scattering. We also demonstrate the performance of (PEA)2SnI4/semi-CNT hybrid phototransistors with ultrahigh photoresponsivity (R) of 6.3 × 104 A/W and detectivity (D*) of ...

Let R be a unital ∗-ring and let a,e,f∈R with e,f invertible Hermitian elements. In this paper, we define two types of outer generalized inverses, called pseudo e-core inverses and pseudo f-dual co...

An effective strategy for regioselective modification and directional assembly of anisotropic nanoparticles is demonstrated to explore the electric field enhancement in assembled gold nanobipyramids compared with gold nanorods. The well-defined secondary plasmonic hot spots between the coupled gold nanobipyramids exhibit the capability for single molecule detection.

Microplastics and organic pollutants are typical contaminants in the marine environment. However, little is known about their interactions. In this study, the sorption of 3,6-Dibromocarbazole(3,6-BCZ) and 1,3,6,8-Tetrabromocarbazole (1,3,6,8-BCZ) by Polypropylene microplastic in simulated seawater was studied. Factors, including particle size, salinity and concentration, were investigated, and the experimental results were simulated using a mathematical model. Results showed that the pseudo-second-order kinetic model was more suitable to describe the sorption of polyhalogenated carbazole by microplastics, with equilibrium sorption times of 6 h and 8 h for 3,6-BCZ and 1,3,6,8-BCZ, respectively. Sorption capacity increased with decreasing particle size and the adsorption capacity increased initially and then decreased with increasing salinity, with a maximum sorption occurring at salinity of 14%. Moreover, the sorption amount increased with the increasing concentration of polyhalogenated carbazole. The sorption isotherms were confirmed as the extended Langmuir model and the extended Freundlich model, both of which were S-type.

Let R be an associative ring with unity 1. The main contribution of this paper is to introduce the notion of generalized quasipolar elements in R as an extension of quasipolar elements of Koliha and Patricio. Several necessary and sufficient conditions of $$a\in R$$ to be generalized quasipolar are derived. Then, we define a class of outer generalized inverses, called weakly generalized Drazin inverses generalizing Koliha’s generalized Drazin inverses. It is shown that $$a\in R$$ has a weakly generalized Drazin inverse if and only if it is generalized quasipolar. Finally, existence criteria for weakly generalized Drazin inverses are obtained.

Let R be an associative ring with unity 1 and let a, b ,c is an element of R. In this paper, several characterizations for left and right hybrid (b, c)-inverses of a are derived. Moreover, their formulae are given by regularities of certain elements. Then, we give characterizations of right (b, c)-inverses and right annihilator (b, c)-inverses of the product of three elements. Finally, relations among the right hybrid (b, c)-inverse of paq, the right (qb, c)-inverse of aq and the right annihilator (b, cp)-inverse of aq are given., The authors are highly grateful to the referee for his/her valuable comments and suggestions which led to improvements of this paper. This research is supported by the National Natural Science Foundation of China (no. 11801124), China Postdoctoral Science Foundation (no. 2020M671068) and the Natural Science Foundation of Anhui Province (no. 1808085QA16) and Portuguese Funds through FCT (Fundcao para a Ciencia e a Tecnologia) within the Projects UIDB/00013/2020 and UIDP/00013/2020.

Background It has been reported that nitric oxide (NO) could ameliorate cadmium (Cd) toxicity in tall fescue; however, the underlying mechanisms of NO mediated Cd detoxification are largely unknown. In this study, we investigated the possible molecular mechanisms of Cd detoxification process by comparative transcriptomic and metabolomic approaches. Results The application of Sodium nitroprusside (SNP) as NO donor decreased the Cd content of tall fescue by 11% under Cd stress (T1 treatment), but the Cd content was increased by 24% when treated with Carboxy-PTIO (c-PTIO) together with Nitro-L-arginine methyl ester (L-NAME) (T2 treatment). RNA-seq analysis revealed that 904 (414 up- and 490 down-regulated) and 118 (74 up- and 44 down-regulated) DEGs were identified in the T1 vs Cd (only Cd treatment) and T2 vs Cd comparisons, respectively. Moreover, metabolite profile analysis showed that 99 (65 up- and 34-down- regulated) and 131 (45 up- and 86 down-regulated) metabolites were altered in the T1 vs Cd and T2 vs Cd comparisons, respectively. The integrated analyses of transcriptomic and metabolic data showed that 81 DEGs and 15 differentially expressed metabolites were involved in 20 NO-induced pathways. The dominant pathways were antioxidant activities such as glutathione metabolism, arginine and proline metabolism, secondary metabolites such as flavone and flavonol biosynthesis and phenylpropanoid biosynthesis, ABC transporters, and nitrogen metabolism. Conclusions In general, the results revealed that there are three major mechanisms involved in NO-mediated Cd detoxification in tall fescue, including (a) antioxidant capacity enhancement; (b) accumulation of secondary metabolites related to cadmium chelation and sequestration; and (c) regulation of cadmium ion transportation, such as ABC transporter activation. In conclusion, this study provides new insights into the NO-mediated cadmium stress response.

The great advances in silicon photonic sensing technology have made it an attractive platform for a wide of sensing applications. However, most silicon photonic sensing platforms suffer from high susceptibility to the temperature fluctuation of operating environment. Additional complex and costly chemical signal enhancement strategies are usually required to improve the signal-to-noise ratio (SNR). Here, a biotoxoid photonic sensor that is resistant to temperature fluctuation have been demonstrated. This novel sensor consists of a ring resonator coupled to a Mach-Zehnder interferometer (MZI) readout unit. Instead of using costly wavelength interrogation, our photonic sensor directly measures the light intensity ratio between the two output ports of MZI. The temperature dependence (TD) controlling section of the MZI is used to eliminate the adverse effects of ambient temperature fluctuation. The simulation and experimental results show a linear relationship between the interrogation function and the concentration of analyte under operation conditions. The thermal drift of the proposed sensor is just 0.18%, which is a reduction of 567 folds for chemical sensing and 28 folds for immuno-biosensing compared to conventional single ring resonator. The SNR increases from 6.85 dB to 19.88 dB within a 2°C temperature variation. The high SNR optical sensor promises great potential for amplification-free of detection of nucleic acids and other biomarkers. Ministry of Education (MOE) National Research Foundation (NRF) Accepted version

In this paper, a novel high-sensitivity optical sensor based on cascaded two Fabry-Perot interferometers (FPIs) has been investigated theoretically and experimentally. In order to improve the sensitivity, the two FP interferometers were designed with slightly different free spectrum ranges (FSRs) to produce Vernier effect. The experimental results showed that the sensitivity of the sensor is 23,794.6 nm/RIU for the wavelength interrogation and 4602.3 dB/RIU for the intensity interrogation, much higher than that of the conventional sensors for the bulk refractive index (RI) sensing. Finally, the reaction between Streptomycin monoclonal antibody and Streptomycin-BSA was measured, showing a great potential for low-cost and portable systems in biochemical sensing.

Tall fescue (Festuca arundinacea Schreb) was widely studied for phytoremediation of organic or heavy metal contaminated soils. However, there is still little information concerning toxicity of chromium (Cr) to tall fescue and roles of nitric oxide (NO) in plants against Cr(VI) stress. In this study, different Cr(VI) treatments (0, 1, 5 and 10 mg/L Cr(VI)) and NO treatments were applied with different combinations in hydroponics culture and their interactions to tall fescue were studied. Specifically, 100 µM sodium nitroprusside (SNP) and 100 µM NG-nitro- L -arginine-methyl ester (L-NAME) treatments were used to apply exogenous NO or inhibit synthesis of NO respectively. Our results showed that tall fescue exhibits comparable Cr(VI) tolerance as wheat (Triticum aestivum L.). Additionally, Cr(VI) accumulation in tall fescue leaves were carefully studied and discussed. Moreover, we observed the significantly increased reactive oxygen species (ROS) contents of tall fescue when subjected to Cr(VI) stress, as well as decreased photosynthetic activities induced by Cr(VI) stress by methods of chlorophyll a fluorescence transient, slow chlorophyll fluorescence kinetics and rapid light response curves. Decreased behaviors of photosynthetic activities may due to destruction of antennae pigments by Cr(VI), ROS burst induced by Cr(VI), and down regulation of photosystem II (PSII) by non-photochemical quenching to avoid over reduction of quinone A, which could be considered as an important strategy to cope with Cr(VI) stress. Meanwhile, exogenous NO treatment improves overall physiological and photosynthetic behaviors of tall fescue against Cr(VI) stress. Moreover, increased translocation factors and improved Cr(VI) tolerance of plants under exogenous NO treatment suggest that SNP treatment could be a useful application for Cr phytoremediation.

Cancer chemotherapy can be hindered by drug resistance which leads to lower drug efficiency. Here, we have developed a drug delivery system that tethers doxorubicin to the surface of gold nanorods via a pH-sensitive linkage (AuNRs@DOX), for a combined photothermal and chemical therapy for cancer. First, AuNRs@DOX is ingested by HepG2 liver cancer cells. After endocytosis, the acidic pH triggers the release of doxorubicin, which leads to chemotherapeutic effects. The gold nanorods are not only carriers of DOX, but also photothermal conversion agents. In the presence of an 808 nm near-infrared laser, AuNRs@DOX significantly enhance the cytotoxicity of doxorubicin via the photothermal effect, which induces elevated apoptosis of hepG2 cancer cells, leading to better therapeutic effects in vitro and in vivo., Highlights • Doxorubicin is tethered on AuNRs with a pH-triggered linkage. • AuNRs@DOX are ingested by cancer cells andrelease doxorubicin under acidic pH triggers. • AuNRs@DOX show excellent combinational chemo- and photothermal therapy effect.

Cadmium (Cd) is a severely toxic heavy metal and environmental pollutant. Tall fescue is a cold season turf grass which has high resistance to Cd as well as the ability to enrich it. To investigate the molecular mechanism underlying the adaptability of tall fescue to Cd stress, RNA-Seq was used to examine Cd stress responses of tall fescue at a transcriptional level. A total of 12 cDNA libraries were constructed from the total RNA of roots or leaves of tall fescue with or without Cd treatments. A total of 2594 (1768 up- and 826 down-regulated) differentially expressed genes (DEGs) were detected in the roots of Cd-stressed tall fescue compared with control roots (R_cd vs R_ck), while only 52 (29 up- and 23 down-regulated) DEGs were found in the leaves of Cd-stressed plants versus the controls (L_cd vs L_ck). The genes encoding glutathione S-transferase (GST), transporter proteins including the ABC transporter, ZRT/IRT-like protein, potassium transporter/channel, nitrate transporter, putative iron-phytosiderophore transporter, copper-transporting ATPase or transporter and multidrug and toxic compound extrusion (MATE) proteins, and numerous transcription factors were found to be significantly induced in Cd-treated roots. In addition, pathogenesis/disease-related gene mRNAs were accumulated in Cd-treated roots of tall fescue. Furthermore, the significantly enriched KEGG pathways in roots were related to 'Glutathione metabolism', 'Ribosome', 'alpha-Linolenic acid metabolism', 'Diterpenoid biosynthesis', 'Sulfur metabolism', 'Phenylpropanoid biosynthesis', 'Protein processing in endoplasmic reticulum', 'Protein export' and 'Nitrogen metabolism'. The study provides novel insights for further understanding the molecular mechanisms of tall fescue responses to Cd stress.

Let R be a unital ∗ -ring. In this paper, we introduce pseudo DMP inverses and generalized m-EP elements in R, which can been seen as extensions of DMP inverses and m-EP matrices, respectively. Als...

Let R be an associative ring with unity 1 and let a,b,c∈R. In this paper, several characterizations for hybrid (b,c)-inverses of a are given. Also, the hybrid (b,c)-inverse of a is characterized by the group inverse of ab, under certain hypothesis. In particular, existence criteria for the the inverse along an element are obtained. Finally, we get the double commutant property and the reverse order law of annihilator (b,c)-inverses.

All-solid-state Z-scheme BCN–TiO2 binary heterostructures with a surface oxygen vacancy layer as the contact interface are fabricated by NaBH4 reduction and ball milling. The effect of the surface oxygen vacancy layer of BCN–TiO2 binary heterostructures on the charge carrier transfer and photocatalytic hydrogen evolution was thoroughly investigated. UV-vis diffuse reflection spectra results reveal that the surface oxygen vacancy can extend the light absorption from the UV to the visible-light region for BCN–TiO2 binary heterostructures. The steady-state/time-resolved photoluminescence spectra exhibit an increased charge carrier lifetime, improved charge carrier separation efficiency and strengthened direct Z-scheme charge transfer process for BCN–TiO2−x heterostructures. As expected, the BCN–TiO2−x heterostructures exhibited a higher visible-light photocatalytic efficiency, about 7 and 11 times higher than that of the pure TiO2 and BCN samples. Namely, the photocatalytic activity of hydrogen evolution can be greatly promoted by constructing the surface oxygen vacancy layer. This work provides a new pathway to construct an efficient contact layer for the direct Z-scheme system to improve the charge carrier separation and transfer and thereby improve the photocatalytic activity.

Strong electric and magnetic dipole in infrared region and higher order multi-pole resonance at visible wavelengths are observed in all-dielectric nanoring metasurfaces. We discuss some of the parameters that influence the optical response of the dielectric nanoring. Adjustment of nanoring radius (inner radius and outer radius) and height can change the absorption intensity and the resonance peaks. Dipole, quadrupole, six-pole and ten-pole resonance modes can be found in the silicon nanoring at resonance wavelength. The transmission spectrum of nanoring with high Q-factor and contrast is achieved with appropriate parameters. Further the nanoring is used to application of sensing in which the sensitivity reaches 228 nm/RIU. This research is an important step to understand resonance in silicon nanoring and paves way for designing some optic devices such as sensor, nanoantennas, and photovoltaics.

Halide perovskite semiconductors exhibit a low intrinsic effective mass of charge carriers; however, their development of transistors is lagging far behind the development of photovoltaic and light-emitting diodes. In this study, we report highly reproducible phenethylammonium tin iodide transistors with mobility over 4 cm2 V−1 s−1 and an on/off ratio over 105 using a simple method of adding a bifunctional additive, urea, into the precursor. This non-volatile Lewis base can modify the crystallization speed and passivate grain-boundary defects, enabling a significant improvement in the transistor characteristics over pristine devices without urea. Furthermore, we demonstrate unprecedented phototransistor characteristics, with detectivity exceeding 1017 Jones when the improved perovskite transistors are used. It is expected that more intensive efforts can be attracted to advance the development of high-performance perovskite (photo)transistors.

Tall fescue (Festuca arundinacea Schreb) is a turf grass species which is widely used for rhizoremediation of organic contaminants and shows notable prospects in heavy metal phytoremediation. In this study, different concentrations of cadmium ion (Cd2+) were applied to study toxic effects of Cd2+ and responses of tall fescue by soilless culture. Tall fescue showed comparable high tolerance to Cd2+ as Indian mustard (Brassica juncea L.). Additionally, the treatment with high concentration of Cd2+ leaded to decreased chlorophyll contents, production of reactive oxygen species (ROS) and lipid peroxidation, as well as damage of cell membrane, necrosis and apoptosis in tall fescue roots, and toxicity of Cd2+ on physiologic properties of tall fescue has been well discussed. Moreover, in photosystem II electron donor side, electron transport from oxygen evolution complex (OEC) to Yz residue of D1 protein was inhibited under high Cd2+ treatments, which may be due to the Cd2+ induced ROS production and the replacement of Ca2+ in the core of OEC. In electron acceptor side, electron transport efficiency from quinone B to photosystem I acceptors increased under high Cd2+ treatments, which may be an important response for plants against Cd2+ toxicity and its mechanism needs our further study.

One-dimensional metal-oxide nanowires are regarded as important building blocks in nanoscale electronics, because of their unique mechanical and electrical properties. In this work, p-type nickel oxide nanowires (NiO NWs) were fabricated by combining sol-gel and electrospinning processes. The poly(vinylpyrrolidone) (PVP) with a molecular weight of 1 300 000 was used as the polymer matrix to increase the viscosity of a NiO precursor solution. The formation and properties of the as-spun NiO/PVP composite NWs before/after calcination treatment were investigated using various techniques. Because of the enhanced adhesion properties between ultraviolet (UV)-treated NiO NWs and the substrate, the field-effect transistors (FETs) based on NiO NWs were found to exhibit satisfying p-channel behaviors. For the fabrication of aligned NiO NW arrays, two parallel conducting Si strips were grounded as NW collector. The integrated FETs based on aligned NiO NWs were demonstrated to exhibit superior electrical performance, compared to the disordered counterparts with the comparable NW coverage. By employing high- k aluminum oxide (Al

Let R be a unital -ring and a, p, q elements of R. When a is regular, and and , we derive the existence criterion and formula of the Moore–Penrose inverses of paq in a ring. Also, we give necessary...

In this paper, double commutativity and the reverse order law for the core inverse are considered. Then, new characterizations of the Moore-Penrose inverse of a regular element are given by one-sided invertibilities in a ring. Furthermore, the characterizations and representations of the core and dual core inverses of a regular element are considered., 19 pages, http://dx.doi.org/10.4153/CMB-2016-045-7

Bermudagrass (Cynodon dactylon) is a typical and widely used warm-season turfgrass. Low temperature is one of the key environmental stress limiting its utility. However, little information is available about the differences of cold response between bermudagrass genotypes. Here, we analyzed antioxidant defense system and fatty acid composition in cold-resistant genotype WBD128 and cold-sensitive genotype WBDg17 exposed to chilling stress. Low temperature (4 °C) significantly decreased the relative water content, whereas increased the H2O2 and O2− contents, more profoundly for WBDg17. Under chilling condition, WBD128 had higher anti O2− activity than WBDg17. Besides, the contents of total glutathione, reduced glutathione (GSH) and its oxidized form (GSSG) were markedly increased by low temperature in both genotypes, whereas WBD128 had significantly higher values of GSH, total glutathione, and GSH/GSSG ratio than WBDg17. Moreover, chilling stress increased saturated fatty acids (SFAs) percentage (palmitic acid and stearic acid) in WBDg17. After chilling treatment, the proportion of linoleic acid decreased in both genotypes, particularly in WBDg17. As for unsaturated fatty acids (UFAs), the percentage of linolenic acid was increased in WBD128. In addition, chilling treatment decreased the values of double bond index (DBI), UFA/SFA ratio as well as degree of unsaturation in WBDg17. Finally, chilling stress altered the expression patterns of the genes, which encode one kind of late embryogenesis abundant proteins (LEA), superoxide dismutase (Cu/Zn SOD) C-repeat-binding factor/DRE-binding factor (CBF1), and peroxidase (POD-2). Collectively, our results revealed that natural variation of chilling tolerance in bermudagrass genotypes may be largely associated with the alterations of antioxidant defense system and fatty acid composition.

Thermo-responsive graphene-polymer films have been obtained by the modification of large CVD graphene films with pyrene-terminated poly( N -isopropylacrylamide) (PNIPAAm) via non-covalent π-π stacking interactions. Pyrene-terminated PNIPAAm was prepared by reversible addition fragmentation chain transfer (RAFT) polymerization using a pyrene-functionalized RAFT agent. Since PNIPAAm possesses a lower critical solution temperature (LCST) of 32 °C, the as-prepared graphene-PNIPAAm films could be reversibly deformed as a result of the morphology response of PNIPAAm to the environmental temperature variation. In addition, the thermo-triggered deformation of the graphene-PNIPAAm films was observed to be reversible and controllable by manipulation of the environmental temperature. Atomic force microscopy (AFM) and high-resolution SEM analysis evidenced the successful attachment of the PNIPAAm on the graphene surface. The thickness of the polymer was revealed by high-resolution scanning electron microscopy (SEM). The successful stepwise fabrication of the CVD graphene-polymer composite films was also characterized using Raman spectroscopy and X-ray photoelectron spectroscopy (XPS). These thermo-responsive composite films would be highly desirable for a wide range of applications, such as thermo-responsive actuators, a thermo-responsive intelligent switch was fabricated using these thermo-responsive graphene composite films.

Solution-processed n-type oxide semiconductors have received great interest in thin-film transistor (TFT) applications. However, solution-processed p-type oxide semiconductors are not as successful as their n-type counterparts because of the lack of material choice and their complicated fabrication procedures. In this study, a simple one-step synthetic method was employed to fabricate a p-type Cu2O thin film via in-situ reaction of a CuI film in aqueous NaOH solution at room temperature. The structure, morphology, and component variations as a function of annealing conditions (≤350 °C) were investigated. The analysis indicates that the phase evolution of Cu2O → Cu2O + CuO → CuO occurred at higher temperatures and the pure CuO phase was achieved at 250 °C. The crystallinity, average grain size, and surface morphology of the CuxO thin films were found to increase in slope as the annealing temperature increased. To explore the possible applications of the obtained CuxO films as semiconducting channel components, bottom-gated TFTs on SiO2 gate dielectrics were constructed and examined. The hole mobility of the optimized device was calculated to be 0.32 cm2 V−1 s−1, along with an on/off current ratio of 5 × 104, and a subthreshold swing of 1.1 V dec−1. The further integration of the CuxO film on an Al2O3 high-k dielectric achieves an improved device performance at 2.5 V. This work successfully demonstrates a simple method to fabricate p-type Cu-based thin films and TFTs via a solution route, which represents a great step towards the development of low-cost and all-oxide complementary metal oxide semiconductor electronics.

A linear polarization converter composed of metal patch arrays and metal chiral metamaterial in the terahertz region is designed and analyzed, which can convert linearly polarized wave to its cross polarization in the transmission mode. Compared with other polarization conversion devices, this device has the advantages of broadband and highly efficiency. The in-depth analysis of physical mechanism is illustrated by using simulated surface current and electrical field distributions.

A one-pot and template-free strategy for synthesizing hollow TiO2 nanostructures (HTSs) is developed by using titanocene dichloride as a titanium source, acetone as a solvent, and ammonia as a basic source. Transmission electron microscopy (TEM) observations demonstrate that the morphology transformation undergoes solid, yolk–shell and then hollow structures, typical of an Ostwald ripening process. Comparative experiments suggest that the mismatched hydrolysis rate of chloride anion and organic cyclopentadiene in unique titanocene dichloride (Cp2TiCl2) molecules should be responsible for the formation of HTSs. The TiO2 nanostructures exhibit controllable morphologies and tunable sizes by mainly adjusting the amounts of the titanium precursor or ammonia. The HTSs show much improved photocatalytic performance as compared with samples of other morphologies in water splitting application, due to the remarkably increased surface area and active sites, and enhanced mass transfer. Our findings reported herein may offer new perspectives in materials chemistry, and energy- and environment-related applications.

A novel scotch tape assisted direct transfer of graphene onto different flexible and rigid substrates, including paper, polyethylene terephthalate, flat and curved glass, SiO2/Si, and a solution-processed high-k dielectric layer is presented. This facile graphene transfer process is driven by the difference in adhesion energy of graphene with respect to tape and a target substrate. In addition, the graphene films transferred by scotch tape are found to be cleaner, more continuous, less doped and higher-quality than those transferred by PMMA. Based on that, the tape transferred graphene is employed as a carrier transport layer in oxide thin-film transistors (TFTs) with different gate dielectrics (i.e., SiO2 and high-k ZrO2). The In2O3/graphene/SiO2 TFTs exhibit a high electron mobility of 404 cm2 V−1 s−1 and a high on/off current ratio of 105, while the counterpart In2O3/graphene/ZrO2 TFTs exhibit improved electron transport properties at an ultra-low operating voltage of 3 V, which is 20 times lower than that of SiO2-based devices. In contrast, the ZrO2-based TFTs with PMMA-transferred graphene exhibit no detective electrical properties. Therefore, the proposed scotch tape assisted transfer method will be particularly useful for the production of graphene films and other two-dimensional materials in more cost-effective and environmentally friendly modes for broad practical applications beyond graphene-based field-effect transistors (GFETs).

Due to the long growth period of plants, phytoremediation is time costly. Improving the accumulation of cadmium (Cd) in shoots of plants will promote the efficiency of phytoremediation. In this study, two senescence-relative phytohormones, abscisic acid (ABA) and salicylic acid (SA), were applied to strengthening phytoremediation of Cd by tall fescue (Festuca arundinacea S.). Under hydroponic culture, phytohormones treatment increased the Cd content of shoots 11.4-fold over the control, reaching 316.3 mg/kg (dry weight). Phytohormones-induced senescence contributes to the transport of heavy metals, and HMA3 was found to play a key role in this process. Additionally, this strategy could strengthen the accumulation of Cu and Zn in tall fescue shoots. Moreover, in soil pot culture, the strategy increased shoot Cd contents 2.56-fold over the control in tall fescue, and 2.55-fold over the control in Indian mustard (Brassica juncea L.), indicating its comprehensive adaptability and potential use in the field. In summary, senescence-induced heavy metal transport is developed as a novel strategy to strengthen phytoremediation. The strategy could be applied at the end of phytoremediation with an additional short duration (7 days) with comprehensive adaptability, and markedly strengthen the phytoremediation in the field.

Arginine methylation is an important posttranslational modification and catalyzed by a family of protein arginine methyltransferases (PRMTs). PRMT7 is the type III PRMT and produces solely monomethylarginine products. PRMT7 has been found to play important roles in multiple biological processes in mammals. However, the expression pattern and function of Prmt7 remain largely unknown in fish. In this study, we characterized the medaka prmt7 gene and determined its expression pattern and function during embryogenesis and germ cell development. The results showed that the chromosomal location and gene structure of medaka prmt7 were similar to its mammalian orthologs. Comparisons of deduced amino acid sequences indicated that medaka Prmt7 was a homolog of human PRMT7 with two methyltransferase domains. Reverse transcription-polymerase chain reaction (RT-PCR) and real time RT-PCR revealed that medaka prmt7 had maternal origin with continuous and dynamical expression during embryonic development. Whole-mount in situ hybridization analysis observed that the transcripts of prmt7 were ubiquitous at morula and gastrula stage, and were later riched in the brain and otic vesicles during embryogenesis. In the adult stage, prmt7 messenger RNA was detected in all examined tissues with the high levels in the ovary and testis. The expression of prmt7 in the gonads was restricted to oocytes of the ovary and spermatids/sperm of the testis. Functional analysis showed that knockdown of medaka prmt7 did not reduce the total number of primordial germ cells (PGCs) in vivo but significantly affected PGCs distribution during embryonic development. These results indicate that prmt7 may be involved in germ cell development in medaka.

Let R be a unital -ring. In this paper, we give several characterizations for the pseudo core and dual pseudo core inverses of an element by units in R. Moreover, their relations with -DMP are obtained. As a special case, the existence criteria for EP elements (-DMP with index 1) are given. Then, the double commutant property of hybrid (b, c)-inverses is considered. Finally, the relations of the inverse along an element and the hybrid (b, c)-inverse, the (dual) pseudo core inverses and the hybrid (b, c)-inverse are investigated., This research is supported by the Fundamental Research Funds for the Central Universities, the Natural Science Foundation of Anhui Province [No. 1808085QA16] and the Portuguese Funds through FCT - 'Fundação para a Ciência e a Tecnologia' , within the project UID-MAT-00013/2013.

Segregation behavior and capturing mechanism of phosphorus (P) in dual-phase steel were systematically investigated by Atom probe tomography (APT). The dual-phase steel is composed of lath martensite, irregular ferrite and MC-carbide (M = Ti, Mo). The P is mainly dissolved in ferrite and martensite grains, and a small amount of P segregates around MC-carbide. APT analysis confirms that the carbide is a type of (Ti, Mo) C. The MC-carbide has a competitive advantage over the ferrite/martensite interface in capturing P atoms. Therefore, it can be concluded that P segregation around the MC-carbide weakens P enrichment at the ferrite/martensite interface. In the end, it is expected that the MC-carbide significantly reduces the P damage to the mechanical properties of dual-phase steel, especially the impact properties.

Chemical vapor deposition (CVD) has recently been considered as the most reliable method to prepare high-quality monolayer graphene films, yet the as-grown graphene usually contains wrinkles and cracks or suffers from discontinuity. These defects can easily result in the shredding of large-sized graphene into small pieces even under a gentle disturbance. Herein, this work presents a cost-effective new method to produce high-quality GQDs by vigorous sonication of defective CVD graphene. The prepared GQDs can be easily and stably dispersed in organic solvents. Morphology and optical properties of the GQDs are investigated using a number of techniques. And we observed the as-prepared GQDs are highly homogeneous, mostly consisted of single-layered graphene, roughly round shapes less than 8 nm in a diameter, and exhibited a strong blue luminescence. Impressively, it is also confirmed that the as-obtained GQDs can act as a promising light absorption material for phototransistor with a hybrid film of GQDs and indium gallium zinc oxide (IGZO) as the channel layer. The GQD/IGZO phototransistor exhibited an appreciated photocurrent, which is 10 times larger than that of the IGZO one when exposed to 270 nm light.

We study the Drazin inverses of the sum and product of two elements in a ring. For Drazin invertible elements $a$ and $b$ such that $a^2b=aba$ and $b^2a=bab$, it is shown that $ab$ is Drazin invertible and that $a+b$ is Drazin invertible if and only if $1+a^Db$ is Drazin invertible. Moreover, the formulae of $(ab)^D$ and $(a+b)^D$ are presented. Thus, a generalization of the main result of Zhuang, Chen et al. (Linear Multilinear Algebra 60 (2012) 903-910) is given.

An improved method for mass production of good-quality graphene nanosheets (GNs) via ball milling pristine graphite with dry ice is presented. We also report the enhanced performance of these GNs as working electrode in lithium-ion batteries (LIBs). In this improved method, the decrease of necessary ball milling time from 48 to 24 h and the increase of Brunauer–Emmett–Teller surface area from 389.4 to 490 m2/g might be resulted from the proper mixing of stainless steel balls with different diameters and the optimization of agitation speed. The as-prepared GNs are investigated in detail using a number of techniques, such as scanning electron microscope, atomic force microscope, high-resolution transmission electron microscopy, selected area electron diffraction, X-ray diffractometer, and Fourier transform infrared spectroscopic. To demonstrate the potential applications of these GNs, the performances of the LIBs with pure Fe3O4 electrode and Fe3O4/graphene (Fe3O4/G) composite electrode were carefully evaluated. Compared to Fe3O4-LIBs, Fe3O4/G-LIBs exhibited prominently enhanced performance and a reversible specific capacity of 900 mAh g−1 after 5 cycles at 100 and 490 mAh g−1 after 5 cycles at 800 mA g−1. The improved cyclic stability and enhanced rate capability were also obtained.

In this study, amorphous indium-tungsten oxide (IWO) semiconductor thin films were prepared by an eco-friendly spin-coating process using ethanol and water as solvents. The electrical properties of IWO thin-film transistors (TFTs), together with the structural and morphological characteristics of IWO thin films, were systematically investigated as functions of tungsten concentration and annealing temperature. The optimized IWO channel layer was then integrated on an aqueous aluminum oxide (AlOx) gate dielectric. It is observed that the solution-processed IWO/AlOx TFT presents high stability and improved characteristics, such as an on/off current ratio of 5 × 107, a field-effect mobility of 15.3 cm2 V−1 s−1, a small subthreshold slope of 68 mV dec−1, and a threshold voltage shift of 0.15 V under bias stress for 2 h. The IWO/AlOx TFT could be operated at a low voltage of 2 V, which was 15 times lower than that of conventional SiO2-based devices. The solution-processed IWO thin films synthesized in a green route would be promising candidates for large-area and high-performance low-cost devices.

Although there are a few research studies on solution-processed p-channel oxide thin-film transistors (TFTs), the strict fabrication conditions and the poor electrical properties have limited their applications in low-power complementary metal oxide semiconductor (CMOS) electronics. Here, the application of the polyol reduction method for processing p-type CuxO and NiOx channel layers and their implementation in TFT devices are reported. The optimized CuxO and NiOx TFTs were achieved at low annealing temperatures (∼300 °C) and exhibited decent electrical properties. Encouraged by the inspiring results obtained on SiO2/Si substrates, the TFT performance was further optimized by device engineering, employing high-k AlOx as the gate dielectric. The fully solution-processed NiOx/AlOx TFT could be operated at a low voltage of 3.5 V and exhibits a high hole mobility of around 25 cm2 V−1 s−1. Our work demonstrates the ability to grow high-quality p-type oxide films and devices via the polyol reduction method over large area substrates while at the same time it provides guidelines for further p-type oxide material and device improvements.

Perovskites have been intensively investigated for their use in solar cells and light-emitting diodes. However, research on their applications in thin-film transistors (TFTs) has drawn less attention despite their high intrinsic charge carrier mobility. In this study, the universal approaches for high-performance and reliable p-channel lead-free phenethylammonium tin iodide TFTs are reported. These include self-passivation for grain boundary by excess phenethylammonium iodide, grain crystallization control by adduct, and iodide vacancy passivation through oxygen treatment. It is found that the grain boundary passivation can increase TFT reproducibility and reliability, and the grain size enlargement can hike the TFT performance, thus, enabling the first perovskite-based complementary inverter demonstration with n-channel indium gallium zinc oxide TFTs. The inverter exhibits a high gain over 30 with an excellent noise margin. This work aims to provide widely applicable and repeatable methods to make the gate more open for intensive efforts toward high-performance printed perovskite TFTs.

The effects of time, temperature, and salinity on the adsorption of Tonalide (AHTN), Musk Xylene (MX), Galaxolide (HHCB), and Musk Ketone (MK) by microplastics of polyethylene (PE) and polyvinyl chloride (PVC) are studied. Results indicate that the equilibrium sorption time was about 10 h and the adsorption kinetics model conformed to the first-order adsorption kinetic model and pseudo-second order kinetic model, this indicates that the main adsorption mechanism might be chemical adsorption and physical absorption. Adsorption reached a nadir at 15 °C and 14% salinity. The adsorption capacity gradually increases, and then decreases, finally increases with an increase in NaCl concentration. Due to the specific surface area and the pore volume of PVC was larger than PE, the adsorption capacity of PVC was higher than that of PE in the equal conditions.

Soil acidification can alter the biogeochemistry of ecosystems and adversely affect biota; however, there are still many debates about the toxicity of aluminum (Al) fractions and Al species in soil:water extracts to plants. In this study, five crude soils with different pH values (4.92-8.51) were collected, seeded with tall fescue and grown in rhizosphere boxes for 120 days. Then, soil properties, labile Al fractions and Al species in soil:water extracts were determined, and their toxicities to plants were analyzed. Our study showed that a stable exchangeable Al fraction (ExAl) pool exists and is supplied by other labile Al fractions. Dissolution of Al from adsorbed hydroxyl-Al fraction (HyAl) and organic-Al fraction (OrAl) may play important roles in soil Al toxicity, as HyAl and OrAl account for major parts of soil labile Al. Additionally, Al3+ and mononuclear hydroxyl-Al species in soil:water extracts have few effects to plants. Nevertheless, high negative correlations were found between Al-F- complexes and tall fescue biomass, indicating their toxicity in the natural soil environment. Thus, in many cases, Al3+ toxicity should not be emphasized because of its lower activity in soil water extracts. Moreover, toxicities of AlF3(aq) and AlF4- to plants should be emphasized, because they have been confirmed in soil water extracts in this study.

Here, room-temperature solution-processed inorganic p-type copper iodide (CuI) thin-film transistors (TFTs) are reported for the first time. The spin-coated 5 nm thick CuI film has average hole mobility (µFE ) of 0.44 cm2 V-1 s-1 and on/off current ratio of 5 × 102 . Furthermore, µFE increases to 1.93 cm2 V-1 s-1 and operating voltage significantly reduces from 60 to 5 V by using a high permittivity ZrO2 dielectric layer replacing traditional SiO2 . Transparent complementary inverters composed of p-type CuI and n-type indium gallium zinc oxide TFTs are demonstrated with clear inverting characteristics and voltage gain over 4. These outcomes provide effective approaches for solution-processed inorganic p-type semiconductor inks and related electronics.

Organic field-effect transistors (OFETs) are the central building blocks of organic electronics, but still suffer from low performance and manufacturing difficulties. This is due in part to the absence of doping, which is mostly excluded from OFET applications for the concern about uncontrollable dopant diffusion. Doping enabled the modern semiconductor industry to build essential components like Ohmic contacts and P-N junctions, empowering devices to function as designed. Recent breakthroughs in organic semiconductors and doping techniques demonstrated that doping can also be a key enabler for high-performance OFETs. However, the knowledge of organic doping remains limited particularly for OFET use. Therefore, this review addresses OFET doping from a device perspective. The paper overviews doping basics and roles in advanced complementary technologies. These fundamentals help to understand why and how doping provides the desired transistor characteristics. Typical OFETs without doping are discussed, with consideration for operating principle and problems caused by the absence of doping. Achievements for channel, contact, and overall doping are also examined to clarify the corresponding doping roles. Finally, doping mechanisms, techniques, and dopants associated with OFET applications are reviewed. This paper promotes fundamental understanding of OFET doping for the development of high-performance OFETs with doped components.