Interlayer Charge Transfer Induced Electrical Behavior Transition in 1D AgI@sSWCNT van der Waals Heterostructures.

The emergence of one-dimensional van der Waals heterostructures (1D vdWHs) opens up potential fields with unique properties, but precise synthesis remains a challenge. The utilization of mixed conductive types of carbon nanotubes as templates has imposed restrictions on the investigation of the electrical behavior and interlayer interaction of 1D vdWHs. In this study, we efficiently encapsulated silver iodide in high-purity semiconducting single-walled carbon nanotubes (sSWCNTs), forming 1D AgI@sSWCNT vdWHs. We characterized the semiconductor-metal transition and increased the carrier concentration of individual AgI@sSWCNTs via sensitive dielectric force microscopy and confirmed the results through electrical device tests. The electrical behavior transition was attributed to an interlayer charge transfer, as demonstrated by Kelvin probe force microscopy. Furthermore, we showed that this method of synthesizing 1D heterostructures can be extended to other metal halides. This work opens the door for the further exploration of the electrical properties of 1D vdWHs.

One-Dimensional High-Entropy Compounds.

One-dimensional (1D) high-entropy compounds (HECs) with subnano diameters are highly attractive because long-range electron delocalization may occur along the high-entropy atomic chain, which results in extraordinary properties. Nevertheless, synthesizing such 1D HECs presents a substantial challenge, and the physicochemical attributes of these novel structures remain ambiguous. Herein, we developed a comelting-filling-freezing-modification (co-MFFM) method for synthesizing 1D high-entropy metal phosphide (HEP) by simultaneously encapsulating various metal cations within single-walled carbon nanotubes (SWCNTs) followed with a phosphorization process. The resulting 1D HEP nanowires confined within SWCNTs exhibit crucial features, including an ultrafine, high-entropy, and amorphous structure, along with a core-shell arrangement. The SWCNT as a shell could donate π electrons to 1D HEP for enhanced electron delocalization and protect 1D HEP as an atomically single-layered protective covering, thus boosting high electrocatalytic activity and stability. Moreover, the co-MFFM method demonstrates scalability for mass production and displays universal applicability to the synthesis of various 1D HECs.

Realization of Ultra-Scaled MoS2 Vertical Diodes via Double-Side Electrodes Lamination.

Schottky diode is the fundamental building blocks for modern electronics and optoelectronics. Reducing the semiconductor layer thickness could shrink the vertical size of a Schottky diode, improving its speed and integration density. Here, we demonstrate a new approach to fabricate a Schottky diode with ultrashort physical length approaching atomic limit. By mechanically laminating prefabricated metal electrodes on both-sides of two-dimensional MoS2, the intrinsic metal-semiconductor interfaces can be well retained. As a result, we demonstrate the thinnest Schottky diode with a length of 2.6 nm and decent rectification behavior. Furthermore, with a diode length smaller than the semiconductor depletion length, the carrier transport mechanisms are investigated and explained by thickness-dependent and temperature-dependent electrical measurements. Our study not only pushes the scaling limit of a Schottky diode but also provides a general double-sided electrodes integration approach for other ultrathin vertical devices.

[Identification and biological characteristics of violet root rot pathogen of Pseudostellaria heterophylla in Fujian province].

Violet root rot is one of the main root diseases in the production process of Pseudostellaria heterophylla. To clarify the pathogenic species that cause the violet root rot of P. heterophylla in Fujian province, the roots and the sclerotia with violet root rot symptoms were collected from the main producing areas of P. heterophylla(Fujian province) from 2017 to 2021, and the pathogens were isolated by tissue separation method and identified by morphology and multi-gene phylogenetic analysis. Additionally, the biological characteristics of the pathogens were studied and the fungicides were determined. The results showed that 78 strains of violet root rot were isolated from the collected root samples, which belonged to one type after preliminary morphological identification. Two represen-tative strains were selected from the pathogens for multi-gene phylogenetic analysis, and they were clustered with Helicobasidium mompa together. The suitable culture conditions for the mycelium were OA medium, 25 ℃, pH 6, and ammonium oxalate as the nitrogen source. The lethal temperature of the mycelium was 50 ℃ for 10 minutes. Moreover, 99.1% propiconazole and 98.7% azoxystrobin had the optimal bacteriostatic effect, and the concentrations with the 50% bacteriostatic rate were 16.85 and 12.24 µg·mL~(-1), respectively. On the basis of the above results, the pathogen causing violet root rot of P. heterophylla in Fujian province was H. mompa. The medium type, growth temperature, pH value, nitrogen source, etc. had significant effect on the growth of mycelium.

[Identification and biological characterization of pathogen causing black spot of Pseudostellaria heterophylla in Fujian province].

In Zherong county, Fujian province, the black spot of Pseudostellaria heterophylla often breaks out in the rainy season from April to June every year. As one of the main leaf diseases of P. heterophylla, black spot seriously affects the yield and quality of the medicinal material. To identify and characterize the pathogens causing black spot, we isolated the pathogens, identified them as a species of Alternaria according to Koch's postulates, and then tested their pathogenicity and biological characteristics. The results showed that the pathogens causing P. heterophylla black spot were A. gaisen, as evidenced by the similar colony morphology, spore characteristics, sporulation phenotype, and the same clade with A. gaisen on the phylogenetic tree(the maximum likelihood support rate of 100% and the Bayesian posterior probability of 1.00) built based on the tandem sequences of ITS, tef1, gapdh, endoPG, Alta1, OPA10-2, and KOG1077. The optimum conditions for mycelial growth of the pathogen were 25 ℃, pH 5-8, and 24 h dark culture. The lethal conditions for mycelia and spores were both treatment at 50 ℃ for 10 min. We reported for the first time the A. gaisen-caused black spot of P. heterophylla. The results could provide a theoretical basis for the diagnosis and control of P. heterophylla leaf spot diseases.

High-stability PGC demodulation technique with an additional sinusoidal modulation based on an auxiliary reference interferometer and EFA.

In the reference interferometer demodulation scheme, it's difficult to guarantee in practice that both interferometers have the same optical path length difference (OPD), which makes the phase modulation depth different in different interferometers with the same laser modulation. The random shift of phase modulation depth also affects the demodulation results. An improved phase-generated carrier (PGC) technique is proposed based on an auxiliary reference interferometer and the ellipse fitting algorithm (EFA). The technique ensures the correct fitting of the EFA for small amplitude signals by introducing a sinusoidal signal as an additional phase modulation. The combination of the reference interferometer and EFA can eliminate the effect of different phase modulation depths of the two interferometers caused by different OPDs, the non-linear distortion caused by phase modulation depth shifts, and improve the accuracy of the demodulation results. The experiment results are consistent with the theoretical analysis, and the method extends the application of the EFA in the reference interferometer phase demodulation technique.

Large-range phase-difference sensing technology for low-frequency strain interrogation.

Phase-difference sensing technology (PDST) has been applied to strain measurement, but its completeness is destroyed by the phase-difference measurement range. A scheme that can realize the completeness of the PDST for low-frequency strain interrogation is proposed. It is built on dual-interferometers and the elliptic-fitting algorithm. To break the measurement range limitation (0, π), a phase compensation setting is applied. The experimental results demonstrate that the method can obtain low-frequency strain signals, and the low-frequency signal whose phase amplitude is greater than π is recovered. The scheme is an efficient and complete method for measuring the strain of low-frequency optical fiber length, which could be applied to low-frequency seismic wave monitoring and rock deformation detection.

Simultaneous measurement of refractive index and temperature or temperature and axial strain based on an inline Mach-Zehnder interferometer with TCF-TF-TCF structure.

A refractive index (RI) and temperature or a temperature and axial strain sensor based on an inline Mach-Zehnder interferometer with thin core fiber (TCF)-thin fiber (TF)-TCF structure is proposed and experimentally demonstrated, requiring only the cleaving and fusion splicing methods. The operation principle depends on the effect that the TF cladding modes interfere with the core mode as an optical coupler. The RI, temperature, or axial strain variations can lead to resonance dip variations in the interferometer spectra, and the RI, temperature, or axial strain sensitivity can be measured by monitoring the wavelength shifts of resonance dips. Then we can measure both RI and temperature, or temperature and axial strain through the demodulation matrix. Four sensors with different TF lengths are fabricated based on numerical simulation. A 15 mm long TF sensor displays an RI sensitivity as high as -174.357nm/RIU, temperature sensitivities in the glycerin solution and the air of 12.47 and 26.19 pm/°C, and axial strain sensitivity of -3.43×10-4nm/µÎµ. Moreover, due to its simple manufacture, high cost-effectiveness and compactness, the proposed sensor has a broad application prospect in physical, chemical, and biological sensing.

Axial strain applied in-fiber Mach-Zehnder interferometer for acceleration measurement.

We present an axial strain applied in-fiber Mach-Zehnder interferometer (MZI) for acceleration measurement. A thin core fiber is sandwiched between two single-mode fibers with core offset to form the MZI. A controlled high fringe visibility in the transmission spectrum is obtained by applying an axial strain, leading to a large slope at the quadrature point. The MZI is then clamped to work as an accelerometer. Experimental results show that the resolution achieves 86 ng/√Hz (g is gravity of 9.8 m/s2), the dynamic range reaches as large as 104.1 dB and the linearity of acceleration response is as high as 99.994%. Moreover, the resonance frequency can be tailored by the clamped fiber length and applied axial strain. The proposed sensor is attractive for practical applications due to low temperature crosstalk, compact size and high sensitivity.

Miniaturized Fabry-Perot probe utilizing PMPCF for high temperature measurement.

We propose a miniaturized optical fiber Fabry-Perot probe for high temperature measurement (up to 1000°C). It is simply fabricated by fusion splicing a short section of polarization-maintaining photonic crystal fiber (PMPCF) with a single-mode fiber (SMF). The interface between the core of the SMF and air holes of the PMPCF, and the end face of the PMPCF work as the mirrors. The pure silica core of the PMPCF is employed as the sensing element. Experimental results show that the probe has a high thermal stability and the temperature sensitivity reaches up to 15.34 pm/°C, which is not affected by the length of the PMPCF. The linearity of temperature response is as high as 99.83%. The proposed sensor has promising prospects in practical applications due to simple fabrication process, low cost, compact size, and excellent repeatability.

Thin fiber-based Mach-Zehnder interferometric sensor for measurement of liquid level, refractive index, temperature, and axial strain.

An all-fiber Mach-Zehnder interferometric sensor capable of measuring liquid level, refractive index (RI), temperature, and axial strain is proposed and experimentally demonstrated. The proposed sensor is based on a fiber ball-thin fiber (TF)-core-offset structure sandwiched between two standard single-mode fibers. The variations of ambient liquid level, RI, temperature, and axial strain cause the change of phase difference between the cladding modes and the core mode, which leads to the shift of interference spectrum. The wavelength shifts of three resonant dips in the transmission spectrum are used to investigate the sensing characteristics of the sensor. Experimental results show that the sensor with TF length of 20 mm exhibits high RI and liquid-level sensitivities of $ - {131.7092}\;{\rm nm/RIU}$-131.7092nm/RIU and $ - {120.7}\;{\rm pm/mm}$-120.7pm/mm at a wavelength of 1589.5 nm. Meanwhile, the sensor is insensitive to temperature and axial strain, and the maximum sensitivities are 0.0390 nm/°C and $ - {4}.{84}\; \times \;{{10}^{ - 4}}\;{\rm nm}/\unicode{x00B5} \varepsilon $-4.84×10-4nm/µÎµ, respectively. In addition, the sensor shows superiority in measuring multiple parameters simultaneously.

High temperature Vernier probe utilizing photonic crystal fiber-based Fabry-Perot interferometers.

This study proposes a highly sensitive and stable optical fiber probe based on Vernier effect for high temperature measurement (up to 1000 °C), utilizing photonic crystal fiber (PCF)-based Fabry-Perot interferometers (FPIs). The cascaded FPIs are fabricated by fusion splicing a section of polarization maintaining PCF to a lead-in single-mode fiber, and then a section of temperature-insensitive hollow core PCF is spliced between the PMPCF and a multi-mode fiber. The shift of the spectral envelope is monitored to measure the temperature variation. Experimental results show that the sensitivities of three fabricated probes are as high as 173.43 pm/ °C, 230.53 pm/ °C and 535.16 pm/ °C when operating from room temperature to 1000 °C, which are consistent with theoretical results. The sensitivities are magnified about 13, 19 and 45 times compared with the single FPI. The linearity of the temperature response is as high as 99.73%. The proposed probe has great application prospects due to compactness, high sensitivity and low cost.

Nitrogen fertilizer application affects lodging resistance by altering secondary cell wall synthesis in japonica rice (Oryza sativa).

Stem mechanical strength is an important agricultural quantitative trait that is closely related to lodging resistance in rice, which is known to be reduced by fertilizer with higher levels of nitrogen. To understand the mechanism that regulates stem mechanical strength in response to nitrogen, we analysed stem morphology, anatomy, mechanical properties, cell wall components, and expression of cell wall-related genes, in two varieties of japonica rice, namely, Wuyunjing23 (lodging-resistant variety) and W3668 (lodging-susceptible variety). The results showed that higher nitrogen fertilizer increased the lodging index in both varieties due to a reduction in breaking strength and bending stress, and these changes were larger in W3668. Cellulose content decreased slightly under higher nitrogen fertilizer, whereas lignin content reduced remarkably. Histochemical staining revealed that high nitrogen application decreased lignin deposition in the secondary cell wall of the sclerenchyma cells and vascular bundle cells compared with the low nitrogen treatments, while it did not alter the pattern of cellulose deposition in these cells in both Wuyunjing23 and W3668. In addition, the expression of the genes involved in lignin biosynthesis, OsPAL, OsCoMT, Os4CL3, OsCCR, OsCAD2, OsCAD7, OsCesA4, and OsCesA7, were also down-regulated under higher nitrogen conditions at the early stage of culm growth. These results suggest that the genes involved in lignin biosynthesis are down-regulated by higher nitrogen fertilizer, which causes lignin deficiency in the secondary cell walls and the weakening of mechanical tissue structure. Subsequently, this results in these internodes with reduced mechanical strength and poor lodging resistance.

Guided Design of Efficient Oxygen Evolution Catalysts Using Patent Analysis.

The facile and rapid design of efficient oxygen evolution reaction (OER) catalysts holds paramount significance for energy conversion devices, such as water electrolyzers and fuel cells. Despite substantial progress in catalyst synthesis and performance exploration, the design and selection processes remain inefficient. In this context, we integrate patent analysis with catalyst design, leveraging the scholarly research functionalities within patent analyses to aid in the design and synthesis of a NiFeRu-carbon catalyst as a high-performance OER catalyst. The results demonstrate that the NiFeRu-Carbon catalyst with low Ru loading (0.3 wt %) exhibits an overpotential of only 219 mV at 10 mA cm-2 under alkaline conditions, and after continuous operation for 200 h, the overpotential only attenuates by 15 mV. The incorporation of high-valence Ru dopants elevated the intrinsic activity of individual catalytic sites within NiFe-layered double hydroxides (LDHs). During the catalytic process, the partial dissolution of Ru might lead to the generation of numerous oxygen vacancies within NiFe- LDH, thereby enhancing the catalyst's activity and stability.

Air Corrosion of Layered Cathode Materials for Sodium-Ion Batteries: Cation Mixing and a Practical Suppression Strategy.

Layered oxide cathodes of sodium-ion batteries (SIBs) are considered promising candidates due to their fascinating high capacity, good cyclability, and environmental friendliness. However, the air sensitivity of layered SIB cathodes causes high electrode manufacturing costs and performance deterioration, hampering their practical application. Herein, a commercial O3-type layered Na(Ni1/3Fe1/3Mn1/3)O2 (NNFM) material is adopted to investigate the air corrosive problem and the suppression strategy. We reveal that once the layered material comes in contact with ambient air, cations migrate from transition metal (TM) layers to sodium layers at the near surface, although Na+ and TM ions show quite different ion radii. Experimental results and theoretical calculations show that more Ni/Na disorder occurs in the air-exposed O3-NNFM materials, owing to a lower Ni migration energy barrier. The cation mixing results in detrimental structural distortion, along with the formation of residual alkali species on the surface, leading to high impedance for Na+ diffusion during charge/discharge. To tackle this problem, an ultrathin and uniform hydrophobic molecular layer of perfluorodecyl trimethoxysilane is assembled on the O3-NNFM surface, which significantly suppresses unfavorable chemistry and structure degradation during air storage. The in-depth understanding of the structural degradation mechanism and suppression strategy presented in this work can facilitate high-energy cathode manufacturing from the perspective of future practical implementation and commercialization.

Comparative analysis of 17 complete chloroplast genomes reveals intraspecific variation and relationships among Pseudostellaria heterophylla (Miq.) Pax populations.

Pseudostellaria heterophylla (Miq.) Pax is a well-known medicinal and ecologically important plant. Effectively distinguishing its different genetic resources is essential for its breeding. Plant chloroplast genomes can provide much more information than traditional molecular markers and provide higher-resolution genetic analyses to distinguish closely related planting materials. Here, seventeen P. heterophylla samples from Anhui, Fujian, Guizhou, Hebei, Hunan, Jiangsu, and Shandong provinces were collected, and a genome skimming strategy was employed to obtain their chloroplast genomes. The P. heterophylla chloroplast genomes ranged from 149,356 bp to 149,592 bp in length, and a total of 111 unique genes were annotated, including 77 protein-coding genes, 30 tRNA genes, and four rRNA genes. Codon usage analysis showed that leucine had the highest frequency, while UUU (encoding phenylalanine) and UGC (encoding cysteine) were identified as the most and least frequently used codons, respectively. A total of 75-84 SSRs, 16-21 short tandem repeats, and 27-32 long repeat structures were identified in these chloroplast genomes. Then, four primer pairs were revealed for identifying SSR polymorphisms. Palindromes are the dominant type, accounting for an average of 47.86% of all long repeat sequences. Gene orders were highly collinear, and IR regions were highly conserved. Genome alignment indicated that there were four intergenic regions (psaI-ycf4, ycf3-trnS, ndhC-trnV, and ndhI-ndhG) and three coding genes (ndhJ, ycf1, and rpl20) that were highly variable among different P. heterophylla samples. Moreover, 10 SNP/MNP sites with high polymorphism were selected for further study. Phylogenetic analysis showed that populations of Chinese were clustered into a monophyletic group, in which the non-flowering variety formed a separate subclade with high statistical support. In this study, the comparative analysis of complete chloroplast genomes revealed intraspecific variations in P. heterophylla and further supported the idea that chloroplast genomes could elucidate relatedness among closely related cultivation materials.

Performance assessment of medical service for organ transplant department based on diagnosis-related groups: A programme incorporating ischemia-free liver transplantation in China.

Background: In July 2017, the first affiliated hospital of Sun Yat-sen university carried out the world's first case of ischemia-free liver transplantation (IFLT). This study aimed to evaluate the performance of medical services pre- and post-IFLT implementation in the organ transplant department of this hospital based on diagnosis-related groups, so as to provide a data basis for the clinical practice of the organ transplant specialty. Methods: The first pages of medical records of inpatients in the organ transplant department from 2016 to 2019 were collected. The China version Diagnosis-related groups (DRGs) were used as a risk adjustment tool to compare the income structure, service availability, service efficiency and service safety of the organ transplant department between the pre- and post-IFLT implementation periods. Results: Income structure of the organ transplant department was more optimized in the post-IFLT period compared with that in the pre-IFLT period. Medical service performance parameters of the organ transplant department in the post-IFLT period were better than those in the pre-IFLT period. Specifically, case mix index values were 2.65 and 2.89 in the pre- and post-IFLT periods, respectively (p = 0.173). Proportions of organ transplantation cases were 14.16 and 18.27%, respectively (p < 0.001). Compared with that in the pre-IFLT period, the average postoperative hospital stay of liver transplants decreased by 11.40% (30.17 vs. 26.73 days, p = 0.006), and the average postoperative hospital stay of renal transplants decreased by 7.61% (25.23 vs.23.31 days, p = 0.092). Cost efficiency index decreased significantly compared with that in the pre-IFLT period (p < 0.001), while time efficiency index fluctuated around 0.83 in the pre- and post-IFLT periods (p = 0.725). Moreover, the average postoperative hospital stay of IFLT cases was significantly shorter than that of conventional liver transplant cases (p = 0.001). Conclusion: The application of IFLT technology could contribute to improving the medical service performance of the organ transplant department. Meanwhile, the DRGs tool may help transplant departments to coordinate the future delivery planning of medical service.

Ultrahigh Mechanical Strength and Robust Room-Temperature Self-Healing Properties of a Polyurethane-Graphene Oxide Network Resulting from Multiple Dynamic Bonds.

Addressing the conflict between achieving high mechanical properties and room-temperature self-healing ability is extremely significant to achieving a breakthrough in the application of self-healing materials. Therefore, inspired by natural spider silk and nacre, a room-temperature self-healing supramolecular material with ultrahigh strength and toughness is developed by synergistically incorporating flexible disulfide bonds and dynamic sextuple hydrogen bonds (H-bonds) into polyurethanes (PUs). Simultaneously, abundant H-bonds are introduced at the interface between graphene oxide nanosheets with dynamic multiple H-bonds and the PU matrix to afford strong interfacial interactions. The resulting urea-containing PU material with an inverse artificial nacre structure has a record mechanical strength (78.3 MPa) and toughness (505.7 MJ m-3), superior tensile properties (1273.2% elongation at break), and rapid room-temperature self-healing abilities (88.6% at 25 °C for 24 h), forming the strongest room-temperature self-healing elastomer reported to date and thus upending the previous understanding of traditional self-healing materials. In addition, this bionic PU-graphene oxide network endows the fabricated flexible intelligent robot with functional repair and shape memory capabilities, thus providing prospects for the fabrication of flexible functional devices.

The first complete chloroplast genome of Briggsia chienii W. Y. Chun and its phylogenetic position within Gesneriaceae.

Briggsia chienii W. Y. Chun 1946 is an endemic herbaceous perennial species distributed in southern China. In this study, we firstly characterized the complete chloroplast genome sequence of B. chienii and provided new molecular resources for promoting its conservation and taxonomic assignment. Its complete chloroplast genome is 154,082 bp in length and contains the typical quadripartite structure of angiosperm plastome, including two inverted repeat (IR) regions of 25,447 bp, a large single-copy (LSC) region of 85,035 bp, and a small single-copy (SSC) region of 18,153 bp. The plastome contains 114 genes, consisting of 80 protein-coding genes, 30 tRNA gene, and 4 rRNA genes. The overall GC content in the plastome of B. chienii is 37.4%, which is lower than lots of angiosperm plastome. The phylogenetic result indicated that B. chienii exhibited the closest relationship with Oreocharis cotinifolia W. T. Wang 1983, and provided new information for the phylogeny relationship of genus Briggsia.

Partially sintered copper‒ceria as excellent catalyst for the high-temperature reverse water gas shift reaction.

For high-temperature catalytic reaction, it is of significant importance and challenge to construct stable active sites in catalysts. Herein, we report the construction of sufficient and stable copper clusters in the copper‒ceria catalyst with high Cu loading (15 wt.%) for the high-temperature reverse water gas shift (RWGS) reaction. Under very harsh working conditions, the ceria nanorods suffered a partial sintering, on which the 2D and 3D copper clusters were formed. This partially sintered catalyst exhibits unmatched activity and excellent durability at high temperature. The interaction between the copper and ceria ensures the copper clusters stably anchored on the surface of ceria. Abundant in situ generated and consumed surface oxygen vacancies form synergistic effect with adjacent copper clusters to promote the reaction process. This work investigates the structure-function relation of the catalyst with sintered and inhomogeneous structure and explores the potential application of the sintered catalyst in C1 chemistry.