Evolution of the Electronic Properties of Tellurium Crystals with Plasma Irradiation Treatment.

Tellurium exhibits exceptional intrinsic electronic properties. However, investigations into the modulation of tellurium's electronic properties through physical modification are notably scarce. Here, we present a comprehensive study focused on the evolution of the electronic properties of tellurium crystal flakes under plasma irradiation treatment by employing conductive atomic force microscopy and Raman spectroscopy. The plasma-treated tellurium experienced a process of defect generation through lattice breaking. Prior to the degradation of electronic transport performance due to plasma irradiation treatment, we made a remarkable observation: in the low-energy region of hydrogen plasma-treated tellurium, a notable enhancement in conductivity was unexpectedly detected. The mechanism underlying this enhancement in electronic transport performance was thoroughly elucidated by comparing it with the electronic structure induced by argon plasma irradiation. This study not only fundamentally uncovers the effects of plasma irradiation on tellurium crystal flakes but also unearths an unprecedented trend of enhanced electronic transport performance at low irradiation energies when utilizing hydrogen plasma. This abnormal trend bears significant implications for guiding the prospective application of tellurium-based 2D materials in the realm of electronic devices.

Progress on Two-Dimensional Transitional Metal Dichalcogenides Alloy Materials: Growth, Characterisation, and Optoelectronic Applications.

Two-dimensional (2D) transitional metal dichalcogenides (TMDs) have garnered remarkable attention in electronics, optoelectronics, and hydrogen precipitation catalysis due to their exceptional physicochemical properties. Their utilisation in optoelectronic devices is especially notable for overcoming graphene's zero-band gap limitation. Moreover, TMDs offer advantages such as direct band gap transitions, high carrier mobility, and efficient switching ratios. Achieving precise adjustments to the electronic properties and band gap of 2D semiconductor materials is crucial for enhancing their capabilities. Researchers have explored the creation of 2D alloy phases through heteroatom doping, a strategy employed to fine-tune the band structure of these materials. Current research on 2D alloy materials encompasses diverse aspects like synthesis methods, catalytic reactions, energy band modulation, high-voltage phase transitions, and potential applications in electronics and optoelectronics. This paper comprehensively analyses 2D TMD alloy materials, covering their growth, preparation, optoelectronic properties, and various applications including hydrogen evolution reaction catalysis, field-effect transistors, lithium-sulphur battery catalysts, and lasers. The growth process and characterisation techniques are introduced, followed by a summary of the optoelectronic properties of these materials.

Phycocyanin - carbon dots nanoprobe for the ratiometric fluorescence determination of peroxynitrite.

As a kind of reactive oxygen species, peroxynitrite is related to various diseases closely such as cancer and neurodegenerative diseases. Constructing probes with highly specific ability and a wide linear detection range for peroxynitrite detection is crucial for understanding the pathogenesis of related diseases and optimizing treatments. In this work, we developed a novel luminescent ratiometric fluorescence nanoprobe (PC-CDs) based on carbon dots and phycocyanin. PC-CDs are constructed by amidation reaction between carbon dots and phycocyanin. The nanoprobe we obtained has a good ability of distinguishing peroxynitrite from other reactive oxygen species and interfering substances. Moreover, the linear range of the nanoprobe is 0.5-100 µM and the limit of detection is 0.5 µM when detecting peroxynitrite. In the spiked recovery experiments under phosphate buffered saline (PBS) environment, our nanoprobe has a good recovery performance and the recovery is 99% - 104%, which will be beneficial to the further development of peroxynitrite testing and the research progress of related diseases. Finally, we discuss the quenching mechanism of peroxynitrite for nanoprobe, and found that there is the combination of dynamic and static quenching in the quenching process.

Atomic-level tungsten doping triggered low overpotential for electrocatalytic water splitting.

The design of electrocatalysts with lower overpotential is of great significance for water splitting. Herein, cobalt hydroxide carbonate (CCH) has been used as a model to demonstrate the boost of its oxygen evolution reaction (OER) activity by atomic doping of W6+ (W-CCH). The 5 at % W doping reduced the OER overpotential of CCH by 95.3 mV at 15 mA cm-2, and increased the current density by 2.8 times at 1.65 V. 5%W-PCCH || 5%W-CCH-based electrolyzer only required a potential of 1.65 V to afford 10 mA cm-2 for full water splitting. The W6+ in CCH are active sites for O2- adsorption and induced an incesaed electron density near the Fermi level, which facilitates the charge transfer during electrocatalysis. The W6+ doping has been validated as an efficient booster for transition-metal carbonate hydroxides-based electrocatalysts, which has half or more than half-filled d-bands.

A TiS2/Celgard separator as an efficient polysulfide shuttling inhibitor for high-performance lithium-sulfur batteries.

The rapid capacity loss caused by the shuttling effect of polysulfides is one of the great challenges of Li-S batteries. In this work, we adopted a simple solid-phase sintering method to synthesize titanium disulfide (TiS2) and further demonstrated it as a superior modifier of separators for Li-S batteries. Two commonly adopted modification processes of separators, including vacuum filtration (VF) and slurry casting (SC) have been used to prepare TiS2/Celgard separators. TiS2-VF/Celgard can better restrain the polysulfide shuttling effect compared with TiS2-SC/Celgard. A TiS2-VF/Celgard-based Li-S battery has a reversible capacity of 771.6 mA h g-1, with a capacity retention of 645.6 mA h g-1 after 500 cycles at 2.0 C, corresponding to a capacity fading rate of ∼0.033% per cycle. This study has shown the potential of TiS2 as a multifunctional modifier of separators for high performance and long cycle life Li-S batteries.

Efficacy and safety of basic fibroblast growth factor in the treatment of burns: Protocol for a systematic review and meta-analysis of randomized controlled trials.

BACKGROUND: To systematically evaluate the efficacy and safety of basic fibroblast growth factor (bFGF) in the treatment of burns and to provide evidence-based medical information for clinicians to choose the appropriate treatment measures for burns. METHODS: Seven databases, including PubMed, the Cochrane Library, Embase, the Chinese Biomedical Literature Database, the Wanfang Database, the China National Knowledge Infrastructure Internet, and the Chongqing Chongqing Weipu Chinese Science and Technology Journal Full-text Database (VIP), were searched by computer. Randomized controlled trials on bFGF in the treatment of burns were collected, and the search was conducted by using a combination of subject terms (MeSH) and free words. The search time limit was from the establishment of each database until January 2019. Two researchers independently screened the literature and extracted the data. According to the evaluation criteria recommended in the Cochrane Handbook for Systematic Reviews of Interventions version 5.3.0, they conducted a rigorous bias risk assessment for the included studies, and Stata 12.0 software was used for meta-analysis. RESULTS: System evaluation and meta-analysis were carried out strictly in accordance with the requirements of the Cochrane Handbook for Systematic Reviews of Interventions version 5.3.0 on meta-analysis and provided a high-quality evaluation of the efficacy and safety of bFGF in the treatment of burns. CONCLUSION: This study provided conclusions from evidence-based medicine and a scientific basis for the efficacy and safety of bFGF in the clinical treatment of burns. ETHICS AND DISSEMINATION: This study was not a clinical trial and therefore did not require ethical approval. The results of this study will be published in an SCI academic journal related to this study in the form of a public publication. PROSPERO REGISTRATION NUMBER: CRD42019124778.

Co2P@N,P-Codoped Carbon Nanofiber as a Free-Standing Air Electrode for Zn-Air Batteries: Synergy Effects of CoNx Satellite Shells.

Here, a free-standing electrode composed of cobalt phosphides (Co2P) supported by cobalt nitride moieties (CoNx) and an N,P-codoped porous carbon nanofiber (CNF) in one-step electrospinning of environmentally friendly benign phosphorous precursors is reported. Physiochemical characterization revealed the symbiotic relationship between a Co2P crystal and surrounding nanometer-sized CoNx moieties embedded in an N,P-codoped porous carbon matrix. Co2P@CNF shows high oxygen reduction reaction and oxygen evolution reaction performance owing to the synergistic effect of Co2P nanocrystals and the neighboring CoNx moieties, which have the optimum binding strength of reactants and facilitate the mass transfer. The free-standing Co2P@CNF air-cathode-based Zn-air batteries deliver a power density of 121 mW cm-2 at a voltage of 0.76 V. The overall overpotential of Co2P@CNF-based Zn-air batteries can be significantly reduced, with low discharge-charge voltage gap (0.81 V at 10 mA cm-2) and high cycling stability, which outperform the benchmark Pt/C-based Zn-air batteries. The one-step electrospinning method can serve as a universal platform to develop other high-performance transition-metal phosphide catalysts benefitting from the synergy effect of transition nitride satellite shells. The free-standing and flexible properties of Co2P@CNF make it a potential candidate for wearable electronic devices.

Total morphosynthesis of biomimetic prismatic-type CaCO3 thin films.

Biomimetic mineralization can lead to advanced crystalline composites with common chemicals under ambient conditions. An exceptional example is biomimetic nacre with its superior fracture toughness. The synthesis of the prismatic layer with stiffness and wear resistance nonetheless remains an elusive goal. Herein, we apply a biomimetic mineralization method to grow prismatic-type CaCO3 thin films, mimicking their biogenic counterparts found in mollusk shells with a three-step pathway: coating a polymer substrate, deposition of a granular transition layer, and mineralization of a prismatic overlayer. The synthetic prismatic overlayers exhibit structural similarity and comparable hardness and Young's modulus to their biogenic counterparts. Furthermore, employment of a biomacromolecular soluble additive, silk fibroin, in fabrication of the prismatic thin films leads to micro-/nano-textures with enhanced toughness and emerging under-water superoleophobicity. This study highlights the crucial role of the granular transition layer in promoting competition growth of the prismatic layer.

O6-Corona[6]arenes with Expanded Cavities for Specific Complexation with C70.

O6-Corona[3]arene[3]tetrazines with expanded cavities were synthesized by one-pot SNAr reaction between 3,6-dichlorotetrazine and aromatic diols. The macrocycle-to-macrocycle transformation involving IEDDA of tetrazine moieties with an enamine followed by denitrogenative aromatization afforded O6-corona[3]arene[3]pyridazines. O6-Corona[6]arenes adopted coronary conformations yielding hexagonal cavities of varied sizes. While O6-corona[3]arene[3]pyridazines complexed both C60 and C70 in a virtually nonselective manner, O6-corona[3]arene[3]tetrazines behaved as selective receptors to complex C70 with K1:1 values up to (3.98 ± 0.08) × 104 M-1 in toluene.

Protective effect of tanshinone IIA against cardiac hypertrophy in spontaneously hypertensive rats through inhibiting the Cys-C/Wnt signaling pathway.

The study aimed to investigate the protective effect of tanshinone IIA against cardiac hypertrophy in spontaneously hypertensive rats (SHRs) through the Cys-C/Wnt signaling pathway. Thirty SHRs were randomly divided into cardiac hypertrophy, low- and high-dose tanshinone IIA groups. Ten Wistar-Kyoto rats were selected as control group. The systolic blood pressure (SBP), heart weight (HW), left ventricular weight (LVW) and body weight (BW) of all rats were recorded. HE staining and qRT-PCR were applied to observe the morphology of myocardial tissue and mRNA expressions of COL1A1 and COL3A1. ELISA and Western blotting were used to measure the serum asymmetric dimethylarginine (ADMA), nitric oxide (NO) and cardiac troponin I (cTnI) levels, and the expressions of the Cys-C/Wnt signaling pathway-related proteins, eNOS and Nox4. Compared with the cardiac hypertrophy group, the SBP, HW/BW, LVW/BW, swelling degree of myocardial cells, COL1A1 and COL3A1 mRNA expressions, serum cTnI and ADMA levels, and the Cys-C/Wnt signaling pathway-related proteins and Nox4 expressions in the low- and high-dose tanshinone IIA groups were decreased, but the endothelial NO synthase (eNOS), phosphorylated eNOS (Ser1177) and NO expressions were increased. No significant difference was found between the low- and high-dose tanshinone IIA groups. Our study indicated a protective effect of tanshinone IIA against cardiac hypertrophy in SHRs through inhibiting the Cys-C/Wnt signaling pathway.

Diagnostic evaluation of appendiceal orifice inflammation in ulcerative colitis.

BACKGROUND/AIMS: To evaluate the diagnostic significance of appendiceal orifice inflammation (AOI) in ulcerative colitis (UC) patients. MATERIALS AND METHODS: We retrospectively examined data from patients with colitis from May 2010 to January 2014 and assigned them to two groups: UC cases and specific colitis cases. First, we clarified the difference in the AOI+ rate between the two groups. Thereafter, imaging findings of all the patients with colitis were re-examined. Features of AOI alone or in combination with proctitis (referred to as "combination features") were considered as the two separate diagnostic criteria for diagnosing UC. By comparing the current diagnoses with the previous diagnoses, evaluation indexes were obtained. RESULTS: A total of 3582 colitis cases (UC cases: 427; specific colitis cases: 3155) were examined. The mean AOI+ rates in UC and specific colitis cases were 26.2% and 0.7%, respectively; a Chi-squared test indicated that the difference between these rates was statistically significant (x2=6.81; p<0.001, OR=50.99). When the AOI features alone were used to diagnose UC, the sensitivity was 26.2% [95% confidence interval (CI), 22.3%-30.6%], agreement rate was 90.6%, and specificity was 99.3% (95% CI, 98.9%-99.5%). When the combination features were used to diagnose UC, the sensitivity was 26.2% (95% CI, 22.3%-30.6%), agreement rate was 91.1%, and specificity was 99.9% (95% CI, 99.7%-100%). CONCLUSION: Combining AOI features and proctitis may lead to a more effective UC diagnosis and enable physicians to identify this condition more promptly among miscellaneous diseases.

Synthesis and Structure of Corona[6](het)arenes Containing Mixed Bridge Units.

A one-pot nucleophilic aromatic substitution reaction of 3,6-dichlorotetrazine with various diphenols and dibenzenethiols produced corona[4]arene[2]tetrazines that contain mixed oxygen, sulfide, methylene, and sulfone linkages. Macrocyclic ring transformations employing an inverse-electron-demand Diels-Alder reaction of tetrazine moieties with enamines and the subsequent sulfide oxidation reaction afforded diverse corona[4]arene[2]pyridazines. The acquired corona[6]arenes adopted three types of conformational structures in the crystalline state.

Graphene homojunction: closed-edge bilayer graphene by pseudospin interaction.

Depending on the sublattices they are propagated in, low-energy electrons or holes are labeled with pseudospin. By engineering pseudospin interactions, we propose that two critical features of a junction, i.e., band gap opening and spatial charge separation, can be realized in graphene layers with proper stacking. We also demonstrate theoretically that such a graphene diode may play a role in future pseudospin electronics such as for harvesting solar energy.

Bandgap-opened bilayer graphene approached by asymmetrical intercalation of trilayer graphene.

A novel graphene structure formed by asymmetrical intercalation of FeCl3 molecules into a trilayer graphene is reported. The trilayer graphene is divided into a single layer and a bilayer graphene by the inserted FeCl3 layer. Theoretical calculation shows that such graphene bilayers with broken inversion symmetry present a prominent opened bandgap of ∼0.13 eV.

Synthesis, structure, and properties of O6 -Corona[3]arene[3]tetrazines.

O6 -Corona[3]arene[3]tetraazines, a new class of macrocyclic compounds, were synthesized efficiently in a one-pot reaction from the nucleophilic aromatic substitution reaction between 1,4-dihydroxybenzene derivatives and 3,6-dichlorotetrazine in warm acetonitrile. In the crystalline structure, the resulting macrocycles adopt highly symmetric structures of a regular hexagonal cavity with all bridging oxygen atoms and tetrazine rings located on the same plane with phenylene units orthogonally orientated. The constitutional aromatic rings are able to rotate around the macrocyclic annulus, depending on the steric effect of the substituents and temperature, in solution. The electron-deficient nature revealed by cyclic voltammetry, differential pulse voltammetry, and characteristic absorbances at a visible region show the O6 -corona[3]arene[3]tetrazines to be suitable macrocyclic receptors for electron-rich guests.

[Investigation of etiology of massive infection with porcine pseudorabies virus in Henan and neighboring Provinces].

In early 2011, the serious outbreak of porcine pseudorabies virus (PRV) infection suddenly recurred in Henan and neighboring Provinces. To investigate the etiology of massive infection with PRV, 16 800 serum samples, 905 porcine epidemic diarrhea virus (PEDV) back-feeding tissues, and 56 PR gene deleted live vaccines were colleted from January 2011 to May 2013 to detect PRV field infection using a PRV gE antibody test kit. The gE and TK genes of 11 new epidemic PRV strains were sequenced by PCR, and their molecular characteristics were analyzed. Moreover, virus titer determination, protective test against PRV, and vaccine potency testing were performed. The results showed that the detection rate of PRV field infection-positive pig farms was 68.06%, and the overall positive rate of PRV field infection in serum was 38.47%; the positive rates in breeding sows, breeding boars, reserve pigs, and commercial pigs were 40.12%, 30.88%, 54.67%, and 26.52%, respectively. The new epidemic strains were in the same evolutionary branch and belonged to the virulent strain group. Compared with the classical PRV strain, the virulence of new epidemic strains changed a little. The length of gE gene was 1 787 bp, and the length of TK gene was 963 bp. The nucleotide homologies of gE and TK genes to Chinese reference strains were 98.2%-99.8% and 98.90%-99.6%, respectively, and the amino acid homologies were 97.1%-99.8% and 97.5%-99.4%, respectively. Commercial vaccine had a 100% protective effect against the new epidemic strains. The positive rate of PRV field infection was 0% in vaccine and 40.44% in back-feeding tissues. The results confirmed that PRV field infection rates were rising sharply among pigs in Henan and neighboring Provinces after 2011. The main virulence genes of new epidemic PRV strains did not change significantly over the years. PR gene deleted live vaccines had no PRV field infection and could completely resist the attack of new strains. The virus carriage of breeding boars and reserve pigs and the serious PRV field infection in PEDV back-feeding tissues were the main causative factors for massive infection with PRV and epidemic outbreak in Henan and neighboring Provinces from 2011 to 2013.

Etching-free patterning method for electrical characterization of atomically thin MoSe2 films grown by chemical vapor deposition.

Patterning two-dimensional materials into specific spatial arrangements and geometries is essential for both fundamental studies of materials and practical applications in electronics. However, the currently available patterning methods generally require etching steps that rely on complicated and expensive procedures. We report here a facile patterning method for atomically thin MoSe2 films using stripping with an SU-8 negative resist layer exposed to electron beam lithography. Additional steps of chemical and physical etching were not necessary in this SU-8 patterning method. The SU-8 patterning was used to define a ribbon channel from a field effect transistor of MoSe2 film, which was grown by chemical vapor deposition. The narrowing of the conduction channel area with SU-8 patterning was crucial in suppressing the leakage current within the device, thereby allowing a more accurate interpretation of the electrical characterization results from the sample. An electrical transport study, enabled by the SU-8 patterning, showed a variable range hopping behavior at high temperatures.

Plasma modified MoS(2) nanoflakes for surface enhanced raman scattering.

Though the SERS effect based on pristine MoS2 is hardly observed, however, the plasma treated MoS2 nanoflakes can be used as an ideal substrate for surface enhanced Raman scattering. It is proved that the structural disorder induced generation of local dipoles and adsorption of oxygen on the plasma treated MoS2 nanosheets are the two basic and important driven forces for the enhancement of Raman signals of surface adsorbed R6G molecules.

Tuning the interface conductivity of LaAlO3/SrTiO3 using ion beams: implications for patterning.

Patterning of the two-dimensional electron gas formed at the interface of two band insulators such as LaAlO3/SrTiO3 is one of the key challenges in oxide electronics. The use of energetic ion beam exposure for engineering the interface conductivity has been investigated. We found that this method can be utilized to manipulate the conductivity at the LaAlO3/SrTiO3 interface by carrier localization, arising from the defects created by the ion beam exposure, eventually producing an insulating ground state. This process of ion-beam-induced defect creation results in structural changes in SrTiO3 as revealed by the appearance of first-order polar TO2 and TO4 vibrational modes which are associated with Ti-O bonds in the Raman spectra of the irradiated samples. Furthermore, significant observation drawn from the magnetotransport measurements is that the irradiated (unirradiated) samples showed a negative (positive) magnetoresistance along with simultaneous emergence of first-order (only second order) Raman modes. In spectroscopic ellipsometry measurements, the optical conductivity features of the irradiated interface are broadened because of the localization effects, along with a decrease of spectral weight from 4.2 to 5.4 eV. These experiments allow us to conclude that the interface ground state (metallic/insulating) at the LaAlO3/SrTiO3 can be controlled by tailoring the defect structure of the SrTiO3 with ion beam exposure. A resist-free, single-step direct patterning of a conducting LaAlO3/SrTiO3 interface has been demonstrated. Patterns with a spatial resolution of 5 µm have been fabricated using a stencil mask, while nanometer scale patterns may be possible with direct focused ion beam writing.

Spin-orbit splitting in single-layer MoS2 revealed by triply resonant Raman scattering.

Although new spintronic devices based on the giant spin-orbit splitting of single-layer MoS(2) have been proposed, such splitting has not been studied effectively in experiments. This Letter reports the valence band spin-orbit splitting in single-layer MoS(2) for the first time, probed by the triply resonant Raman scattering process. We found that upon 325 nm laser irradiation, the second order overtone and combination Raman modes of single-layer MoS(2) are dramatically enhanced. Such resonant Raman enhancement arises from the electron-two-phonon triple resonance via the deformation potential and Fröhlich interaction. As a sensitive and precise probe for the spin-orbit splitting, the triply resonant Raman scattering will provide a new and independent route to study the spin characteristics of MoS(2).