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Titanium (Ti)-based metal-organic frameworks (Ti-MOFs) have attracted intensive research attention due to their low toxicity and high abundance of titanium. However, limited by the high reactivity of titanium species in the reaction system, the construction of Ti-MOFs still faces great challenges. Herein, we successfully introduced Ti into MOF-74 using a one-pot method. Powder X-ray diffraction (PXRD) combined with X-ray photoelectron spectroscopy (XPS) and inductively coupled plasma (ICP) spectroscopy confirmed that the Ti­(IV) ions were uniformly inserted into the MOF-74 structure. Our scanning electron microscopy (SEM)/energy-dispersive spectrometry (EDS) analysis showed that the Ti content was up to 44% with good sample homogeneity. The adsorption selectivity of Ti0.44/Ni0.56-MOF-74 at 1.0 bar and 298 K for C2H2/C2H4 and C2H2/CO2 (50/50, v/v) mixtures was 4.9 and 6.8, respectively, which are higher than that of pristine Ni-MOF-74. The results of our breakthrough simulation experiments revealed that the adsorption and separation performances of Ti0.44/Ni0.56-MOF-74 were greatly improved. This study provided insights for the construction of Ti-based bimetallic MOFs used for the separation of light hydrocarbons.

Abstract High tunability of photoconductivity is highly desired for applications in optical memories, sensors, and bioelectronics. Recently, room temperature persistent photoconductivity (PPC) in SrTiO3 (STO) has been revealed and has attracted great attention. However, reversible switching of the PPC in STO with a large on/off ratio remains challenging to date. Here, a giant switchable PPC in soft chemistry reduced STO is reported. An initial insulator‐to‐metal transition with on/off ratio up to 7 orders of magnitude is observed and about 5 orders of magnitude transition is found to be reversible. Via nuclear magnetic resonance measurements, it is uncovered that such unusual PPC is driven by the generation of excess carriers accompanied with a configuration evolution of the incorporated hydrogen from hydridic HO+ to protic Hi+ upon illumination. The work demonstrates giant switchable PPC transition in soft chemistry reduced perovskite oxides, providing a new platform for pursuing high performance sensors and nonvolatile optoelectronic memory devices.

Integrating ferroelectric perovskite oxides on Si is highly desired for electronic applications but challenging. Here, the authors show emergent in-plane ferroelectricity and promising nonvolatile memories based on resistive domain wall in BaTiO3/Si.

Solid adsorbents that simultaneously have high selectivity and uptake capacity are highly promising as alternatives to conventional cryogenic distillation of propene/propane (C3H6/C3H8) separation. Coordinatively unsaturated metal sites (CUS) plays a vital role in selective adsorption of olefins over paraffins. Ultrathin poly (triazine imide) (PTI) nanosheets can reach rapid gas adsorption equilibrium, due to its large surface-to-volume ratio. In this work, combining the advantages of the CUS and the PTI nanosheets, Li CUSs were introduced into the PTI nanosheets for C3H6/C3H8 separation. Density functional theory (DFT) calculations demonstrated the thermodynamic feasibility of incorporating Li CUSs into the PTI nanosheets. These highly exposed Li CUSs were predicted to have a higher adsorption affinity toward C3H6 than C3H8. Using the DFT-derived force field parameters, we further performed grand canonical Monte Carlo (GCMC) simulations to investigate C3H6/C3H8 adsorption on the Li–PTI complexes slit pore model with different pore widths (H). We found that the Li–PTI complexes display considerable C3H6/C3H8 selectivity (4.2–7.9) under relevant conditions. Moreover, the Li–PTI complexes slit pore have large C3H6 working capacities (1.5–4.0 mmol g−1), superior to those calculated for the most of adsorbent materials that have been reported. The Li–PTI complexes with slit pore architecture show potential as C3H6/C3H8 separation materials.

The purpose of this study is to compare five protocols of estrous synchronization for Hu ewes to obtain the most effective and economical protocol, to apply the advantageous scheme in large-scale sheep farming. Healthy multiparous Hu ewes (n = 150) were randomly divided into five groups, and all ewes were administered fluorogestone acetate (FGA, 45 mg) vaginal sponge. The sponges of the first three groups (Groups I, II, and III) were removed on the 11th day, and 0.1 mg of PGF2α was injected intramuscularly on the ninth day. Group I received 6 μg of gonadotropin-releasing hormone (GnRH) by intramuscular injection at 36th h after withdrawal of the sponge. Group II was injected 330 IU of pregnant mare serum gonadotropin (PMSG) on the ninth day. The combination of 6 μg of GnRH and 330 IU of PMSG was treated in Group III at the same time as Group I and Group II. The sponges of the latter two groups (Groups IV and V) were removed on the 13th day, and 330 IU of PMSG was injected intramuscularly simultaneously. PGF2α (0.1 mg) was administered on the 12th day in Group IV. All ewes were detected for estrus at 24, 36, 48, 60, and 72 h after the sponge removal. The loss of sponge and vaginitis was recorded when the sponge was withdrawn. Cervical artificial insemination (AI) was performed with fresh semen of Dorper rams diluted with skimmed milk. After 30 days of insemination, the conception was detected with a veterinary B-ultrasound scanner. The lambing status of all ewes and the cost of drugs for estrous synchronization in each group were recorded. The results showed the following: (1) on the whole, the average percentage of estrous ewes in the period of 24–36 h and 36–48 h after removal was significantly higher than other three periods and that of the period of 60–72 h was significantly lower than the first three periods after removal; (2) there was no significant difference in percentages of estrous ewes in any of the five time periods, sponge loss rate, vaginitis rate, total percentage of estrous ewes, conception rate, single lambing rate, twinning rate, and multiple lambing rate of ewes among five protocols; (3) total percentage of estrous ewes and conception rate were more than or equal to 80% in the Groups II and III, and the twinning lamb rate of the Group II protocol was 70%; (4) there was no difference in lambing rate of ewes among Groups II, III, IV, and V; (5) the Group III had the highest drug cost of 22.5 CNY. In conclusion, considering the lambing rate, twinning lamb rate, and drug cost for estrous synchronization, Group II was the most advisable for application and promotion in large-scale sheep farms among these five protocols of estrus synchronization.

The recent discovery of superconductivity in infinite-layer nickelate films has aroused great interest since it provides a new platform to explore the mechanism of high-temperature superconductivity. However, superconductivity only appears in the thin film form and synthesizing superconducting nickelate films is extremely challenging, limiting the in-depth studies on this compound. Here, we explore the critical parameters in the growth of high-quality nickelate films using molecular beam epitaxy. We found that stoichiometry is crucial in optimizing the crystalline structure and realizing superconductivity in nickelate films. In precursor NdNiO3 films, optimal stoichiometry of cations yields the most compact lattice while off-stoichiometry of cations causes obvious lattice expansion, influencing the subsequent topotactic reduction and the emergence of superconductivity in infinite-layer nickelates. Surprisingly, in-situ reflection high energy electron diffraction indicates that some impurity phases always appear once Sr ions are doped into NdNiO3 although the X-ray diffraction data are of high quality. While these impurity phases do not seem to suppress the superconductivity, their impacts on the electronic and magnetic structure deserve further studies. Our work demonstrates and highlights the significance of cation stoichiometry in the superconducting nickelate family.

The flue gas from fossil fuel power plants is a long-term stable and concentrated emission source of CO2, and it is imperative to reduce its emission. Adsorbents have played a pivotal role in reducing CO2 emissions in recent years, but the presence of water vapor in flue gas poses a challenge to the stability of adsorbents. In this study, ZIF-94, one of the ZIF adsorbents, showed good CO2 uptake (53.30 cm3/g), and the calculated CO2/N2 (15:85, v/v) selectivity was 54.12 at 298 K. Because of its excellent structural and performance stability under humid conditions, the CO2/N2 mixture was still well-separated on ZIF-94 with a separation time of 30.4 min when the relative humidity was as high as 99.2%, which was similar to the separation time of the dry gas experiments (33.2 min). These results pointed to the enormous potential applications of ZIF-94 for CO2/N2 separation under high humidity conditions in industrial settings.

The basic principle of nonlocal means is to denoise a pixel using the weighted average of the neighbourhood pixels, while the weight is decided by the similarity of these pixels. The key issue of the nonlocal means method is how to select similar patches and design the weight of them. There are two main contributions of this paper: The first contribution is that we use two images to denoise the pixel. These two noised images are with the same noise deviation. Instead of using only one image, we calculate the weight from two noised images. After the first denoising process, we get a pre-denoised image and a residual image. The second contribution is combining the nonlocal property between residual image and pre-denoised image. The improved nonlocal means method pays more attention on the similarity than the original one, which turns out to be very effective in eliminating gaussian noise. Experimental results with simulated data are provided.

Our previous studies have shown that SET7/9 promotes hepatocellular carcinoma cells proliferation, invasion and migration via post-translational regulation of E2F1. In this study, we comprehensively analyzed the functions and mechanisms of the SET7/9-E2F1 axis using data mining. Data from the UALCAN database showed abnormal expression of both SET7/9 and E2F1 in multiple cancer types. Survival curves and correlation analysis by GEPIA supported the significant roles of SET7/9 and E2F1 in the progression of HCC. Functional enrichment analysis suggested that the SET7/9-E2F1 axis is involved in the regulation of cell cycle, DNA repair and replication, and gene transcription. Our results implicated the potential of SET7/9 in combination with E2F1 as novel therapeutic targets and prognostic biomarkers in hepatocellular carcinoma. [ABSTRACT FROM AUTHOR]

A pore engineering strategy involving the regulation of pillars in a series of pillar-layered metal–organic frameworks was presented to promote pore size adjustment and pore environment optimization for efficient separation of CH4 from coal-mine methane. Compared with the original Ni(BTC)(BPY) and Ni(BTC)(TED), the suitable pore size and rich supply of carboxylate oxygens in the newly constructed Ni(BTC)(PIZ) resulted in the strongest recognition of CH4, leading to both high CH4 uptake (1.62 mmol/g) and CH4/N2 (50/50) selectivity (7.32) at 298 K and 1 bar. Its optimal balance performance between uptake and selectivity was better than most reported adsorbents, which further led to the most efficient separation of CH4 from CH4/N2 mixtures. The stability of the structure and performance was verified by repeated cycle tests. Overall, it is believed the structure constructed based on the regulation strategy of the interlayer channel would enable the application of promising metal–organic frameworks in industrial gas separation processes. [ABSTRACT FROM AUTHOR]

I-III-VI2 chalcopyrites have unique inherent crystal structure defects, and hence are potential candidates for thermoelectric materials. Here, we identified mixed polyanionic/polycationic site defects (ZnIn-, VCu-,InCu2+ and/or ZnCu+) upon Zn substitution for either Cu or In or both in CuInTe2, with the ZnIn- species originating from the preference of Zn for the cation 4b site. Because of the mutual reactions among these charged defects, Zn substitution in CuInTe2 alters the basic conducting mechanism, and simultaneously changes the lattice structure. The alteration of the lattice structure can be embodied in an increased anion position displacement (u) or a reduced bond length difference (Δd) between d(Cu-Te)4a and d(In-Te)4b with increasing Zn content. Because of this, the lattice distortion is diminished and the lattice thermal conductivity (κL) is enhanced. The material with simultaneous Zn substitution for both Cu and In had a low κL, thereby we attained the highest ZT value of 0.69 at 737 K, which is 1.65 times that of Zn-free CuInTe2. [ABSTRACT FROM AUTHOR]