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A new lvt-type metal–organic framework UTSA-60a with suitable pore channels and open metal sites has been developed for highly selective separation of C2H2/C2H4 at room temperature. [ABSTRACT FROM AUTHOR]

To modulate stepwise photochromism by shifting ring-closure absorption of the dithienylethene (DTE) moiety, trans-Pt(PEt3)2(C=C-DTE)2 [C=C-DTE = L10 (100), L20 (200), L3o (300), and L40 (400)] and cis-Pt(PEt3)2(L40)2 (500) with two identical DTE-acetylides were elaborately designed. With the gradual red shift of ring-closure absorption for L1c (441 nm) → L2c (510 nm) → L3c (556 nm) → L4c (602 nm), stepwise photochromism is increasingly facilitated in trans-Pt(PEt3)2(C=C-DTE)2 following 100 → 200 → 300 → 400. The conversion percentage of singly ring-closed 2co-4co to dually ring-closed 2cc-4cc at the photostationary state is progressively increased in the order 1cc (0%) → 2cc (18%) → 3cc (67%) → 4cc (100%). Compared with trans-arranged 400, stepwise photochromism in the corresponding cis-counterpart 500 is less pronounced, ascribed to either direct conversion of 500 to 5cc or rapid conversion of 5co to 5cc. The progressively facile stepwise photocyclization following 200 → 300 → 400 is reasonably interpreted by gradually enhanced transition character involving LUMO+1, which is the only unoccupied frontier orbital responsible for further photocyclization of singly ring-closed 2co-4co. [ABSTRACT FROM AUTHOR]

PURPOSE: To observe the effect of immediate construction of mandibular defect with or without teeth missing by bone composite and absorbable Bio-gide membrane. METHODS: 40 New Zealand rabbits were randomly divided into 3 groups. For the mandibular defect, group A was filled with nothing, group B was filled with bone composite and Bio-gide membrane, group C was filled with bone composite and Bio-gide membrane as well as autogenous tooth implantation. The rabbits were sacrificed 4,8,12 weeks after surgery for evaluation of gross morphology, X-ray and histopathology. RESULTS: After 12 weeks, the defect in group A was still there but narrower, the defect in group B was filled with new bone, the density of which was same to the bone X-ray, and lamellar bone were under microscope, the implanted teeth in group C had been fixed tightly in 17 animals, no transparent areas in 13 animals from X-ray, but absorbable areas in 13 animals under microscope were noted. CONCLUSIONS: Immediate construction of mandibular defect with bone composite and Bio-guide membrane is feasible and effective, autogeneous tooth implantation on the construction area is also stable. [ABSTRACT FROM AUTHOR]

SnO 2 -based nanostructures have been extensively studied as excellent hydrogen sensing materials. While Pd loading was employed to enhance sensing performance, many reported that Pd-loaded SnO 2 (denoted as Pd/SnO 2) experienced signal saturation at high H 2 concentration, limiting the detection range and leaving the sensing mechanism unclear. Herein, we report a Pd/SnO 2 nanoparticle (NP) film-based H 2 sensor fabricated using gas-phase cluster beam deposition, achieving wide-concentration-range hydrogen detection (1.5 ppm - 10%). It was found that there are two H 2 concentration-dependent sensing mechanisms. Below 1% H 2 concentration, the response correlated linearly with the square root of the H 2 concentration, predominantly due to the electronic coupling effect at the interface between palladium hydride (PdH x) and SnO 2 , realizing a high sensitivity of 0.23 ppm−1. As concentration increased further, a linear dependence between the response and H 2 concentration was observed with a sensitivity of 0.018 ppm−1, which stemmed from the redox reaction between H atoms and O α − on the SnO 2 surface. Additionally, the device's sensing kinetics were meticulously analyzed. Pd loading drastically reduced the response time by reducing apparent activation energy. Furthermore, our sensor exhibited notable selectivity, reproducibility, and long-term stability. [Display omitted] • Pd/SnO 2 NP film-based H 2 sensor fabricated via gas-phase cluster beam deposition. • The sensor exhibits excellent sensitivity across 1.5 ppm – 10% H 2 concentration. • It was found that there are two H 2 concentration-dependent sensing mechanisms. • The sensing kinetics were meticulously analyzed. [ABSTRACT FROM AUTHOR]

Hydrogen (H 2 ) is crucial in the future global energy landscape due to its eco-friendly properties, but its flammability requires precise monitoring. This study introduces an innovative thermocatalytic H 2 sensor utilizing ultrathin mica sheets as substrates, coated on both sides with Pd nanocluster (NC) films. The ultrathin mica substrate ensures robustness and flexibility, enabling the sensor to withstand high temperatures and mechanical deformation. Additionally, it simplifies the fabrication process by eliminating the need for complex microelectro-mechanical systems (MEMS) technology. Constructed through cluster beam deposition, the sensor exhibits exceptional characteristics, including a wide concentration range (from 500 ppm to 4%), rapid response and recovery times (3.1 and 2.4 s for 1% H 2 ), good selectivity, high stability, and repeatability. The operating temperature can be as low as 40 °C, achieving remarkably low power consumption. The study explores the impact of double-sided versus single-sided catalytic layers, revealing significantly higher sensitivity and response with the double-sided configuration due to the increased catalytic surface area. Additionally, the research investigates the relationship between the deposition amount of Pd NCs and the sensor's sensitivity, identifying an optimal value that maximizes performance without excessive use of Pd. The sensor's innovative design and excellent performance position it as a promising candidate for meeting the demands of a hydrogen-based energy economy.

In this study, we successfully synthesize palladium-decorated indium trioxide (Pd/In 2 O 3 ) hybrid nanoclusters (NCs) using an advanced dual-target cluster beam deposition (CBD) method, a significant stride in developing high-performance ethanol sensors. The prepared Pd/In 2 O 3 hybrid NCs exhibit exceptional sensitivity, stability, and selectivity to low concentrations of ethanol vapor, with a maximum response value of 101.2 at an optimal operating temperature of 260 °C for 6 at% Pd loading. The dynamic response of the Pd/In 2 O 3 -based sensor shows an increase in response with increasing ethanol vapor concentrations within the range of 50 to 1000 ppm. The limit of detection is as low as 24 ppb. The sensor exhibits a high sensitivity of 28.24 ppm -1/2 , with response and recovery times of 2.7 and 4.4 seconds, respectively, for 100 ppm ethanol vapor. Additionally, the sensor demonstrates excellent repeatability and stability, with only a minor decrease in response observed over 30 days and notable selectivity for ethanol compared to other common volatile organic compounds. The study highlights the potential of Pd/In 2 O 3 NCs as promising materials for ethanol gas sensors, leveraging the unique capabilities of CBD for controlled synthesis and the catalytic properties of Pd for enhanced gas-sensing performance.

Realization of ethane-selective porous materials for efficient ethane/ethylene (C 2 H 6 /C 2 H 4 ) separation is an important task in the petrochemical industry. Although a number of C 2 H 6 -selective adsorbents have been realized, their adsorption capacity and selectivity might be mostly dampened under humid conditions due to structure decomposition or co-adsorption of water vapor. A desired material should have simultaneously high C 2 H 6 uptake and selectivity, excellent water stability, and ultralow water adsorption uptake for industrial applications, but such a material is elusive. Herein, we report a chemically stable hafnium-based material (Hf)DUT-52a, featuring the suitable pore apertures and less hydrophilicity for highly efficient C 2 H 6 /C 2 H 4 separation under humid conditions. Gas sorption results reveal that (Hf)DUT-52a exhibits both high ethane adsorption capacity (4.02 mmol g -1 ) and C 2 H 6 /C 2 H 4 selectivity (1.9) at 296 K and 1 bar, which are comparable to the majority of the top-performing materials. Most importantly, the less pore hydrophilicity enables (Hf)DUT-52a to exhibit a negligible water uptake of 0.036 g g -1 before 40% relative humidity (RH), effectively minimizing the impact of humidity on separation capacity. This material thus shows excellent separation capacity even under 40% RH with a high polymer-grade ethylene production capacity up to 8.43 L kg -1 at ambient conditions, as evidenced by the breakthrough experiments.

The realization of porous materials for highly selective separation of acetylene (C 2 H 2 ) from various other gases (e.g., carbon dioxide and ethylene) by adsorption is of prime importance but challenging in the petrochemical industry. Herein, a chemically stable Hofmann-type metal-organic framework (MOF), Co(pyz)[Ni(CN) 4 ] (termed as ZJU-74a), that features sandwich-like binding sites for benchmark C 2 H 2 capture and separation is reported. Gas sorption isotherms reveal that ZJU-74a exhibits by far the record C 2 H 2 capture capacity (49 cm 3 g -1 at 0.01 bar and 296 K) and thus ultrahigh selectivity for C 2 H 2 /CO 2 (36.5), C 2 H 2 /C 2 H 4 (24.2), and C 2 H 2 /CH 4 (1312.9) separation at ambient conditions, respectively, of which the C 2 H 2 /CO 2 selectivity is the highest among all the robust MOFs reported so far. Theoretical calculations indicate that the oppositely adjacent nickel(II) centers together with cyanide groups from different layers in ZJU-74a can construct a sandwich-type adsorption site to offer dually strong and cooperative interactions for the C 2 H 2 molecule, thus leading to its ultrahigh C 2 H 2 capture capacity and selectivities. The exceptional separation performance of ZJU-74a is confirmed by both simulated and experimental breakthrough curves for 50/50 (v/v) C 2 H 2 /CO 2 , 1/99 C 2 H 2 /C 2 H 4 , and 50/50 C 2 H 2 /CH 4 mixtures under ambient conditions., (© 2020 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Capturing carbon dioxide (CO 2 ) from flue gases with porous materials has been considered as a viable alternative technology to replace traditional liquid amine adsorbents. A large number of microporous metal-organic frameworks (MOFs) have been developed as CO 2 -capturing materials. However, it is challenging to target materials with both extremely high CO 2 capture capacity and gas selectivity (socalled trade-off) along with moderate regeneration energy. Herein, we developed a novel porous material, [Cu(dpt) 2 (SiF 6 )] n (termed as UTSA-120; dpt = 3,6-di(4-pyridyl)-1,2,4,5-tetrazine), which is isoreticular to the net of SIFSIX-2-Cu-i. This material exhibits simultaneously high CO 2 capture capacity (3.56 mmol g -1 at 0.15 bar and 296 K) and CO 2 /N 2 selectivity (~600), both of which are superior to those of SIFSIX-2-Cu-i and most other MOFs reported. Neutron powder diffraction experiments reveal that the exceptional CO 2 capture capacity at the low-pressure region and the moderate heat of CO 2 adsorption can be attributed to the suitable pore size and dual functionalities (SiF6 2- and tetrazine) which not only interact with CO 2 molecules but also enable the dense packing of CO 2 molecules within the framework. Simulated and actual breakthrough experiments demonstrate that UTSA-120a can efficiently capture CO 2 gas from the CO 2 /N 2 (15/85, v/v) and CO 2 /CH 4 (50/50) gas mixtures under ambient conditions., Competing Interests: Conflicts of interest There are no conflicts to declare.

Separation of propyne/propylene (C 3 H 4 /C 3 H 6 ) is more difficult and challenging than that of acetylene/ethylene (C 2 H 2 /C 2 H 4 ) because of their closer molecular sizes. A comprehensive screening of a series of metal-organic frameworks with broad types of structures, pore sizes, and functionalities was carried out. UTSA-200 was identified as the best separating material for the removal of trace C 3 H 4 from C 3 H 4 /C 3 H 6 mixtures. Gas sorption isotherms reveal that UTSA-200 exhibits by far the highest C 3 H 4 adsorption capacity (95 cm 3  cm -3 at 0.01 bar and 298 K) and record C 3 H 4 /C 3 H 6 selectivity, which was mainly attributed to the suitable dynamic pore size to efficiently block the larger C 3 H 6 molecule whilst the strong binding sites and pore flexibility capture smaller C 3 H 4 . This material thus provides record purification capacity for the removal of C 3 H 4 from a 1:99 (or 0.1:99.9, v/v) C 3 H 4 /C 3 H 6 mixture to produce 99.9999 % pure C 3 H 6 with a productivity of 62.0 (or 142.8) mmol g -1 ., (© 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

A dust explosion at the Formosa Fun Coast water park in Taiwan caused nearly 500 burn injury cases. One hundred of these cases involved burns over more than 20% of the total body surface area. This tragedy inundated hospitals across northern Taiwan with an unprecedented number of burn patients. Significant manpower and medical resources were targeted on related resuscitation and treatment efforts, with support and assistance provided by agencies and organizations nationwide. Most of the burn patients were young people in their teens and twenties, whose severe burns posed the greatest threat and challenge to their lives so far. Furthermore, their experience presented major psychosocial and physical health challenges. Patients received an array of clinical treatments such as debridement, skin grafting, dressing, and rehabilitation. Debilitating pain, skin damage, changes to body image, physical disabilities, helplessness, sadness, and anxiety have not only deeply affected the patients physically and psychologically but also created significant life stresses for their family members / companions, which requires counseling in order to facilitate emotional healing. Although burn patients gradually recover as they pass through the acute, recovery, and rehabilitation phases, they will face the challenges of lifelong rehabilitation after discharge. I hope that these young victims will take courage and be brave and strong in dealing with the difficulties and challenges of daily life and will embrace the future with hope as they enter the dawn of their new life.

Purpose: To observe the effect of immediate construction of mandibular defect with or without teeth missing by bone composite and absorbable Bio-gide membrane., Methods: 40 New Zealand rabbits were randomly divided into 3 groups. For the mandibular defect, group A was filled with nothing, group B was filled with bone composite and Bio-gide membrane, group C was filled with bone composite and Bio-gide membrane as well as autogenous tooth implantation. The rabbits were sacrificed 4,8,12 weeks after surgery for evaluation of gross morphology, X-ray and histopathology., Results: After 12 weeks, the defect in group A was still there but narrower, the defect in group B was filled with new bone, the density of which was same to the bone X-ray, and lamellar bone were under microscope, the implanted teeth in group C had been fixed tightly in 17 animals, no transparent areas in 13 animals from X-ray, but absorbable areas in 13 animals under microscope were noted., Conclusions: Immediate construction of mandibular defect with bone composite and Bio-guide membrane is feasible and effective,autogeneous tooth implantation on the construction area is also stable.

Reaction of Pt(dppm-P,P')Cl2 (dppm = 1,2-bis(diphenylphosphino)methane) with HCCPhtpy (HCCPhtpy = 4'-(4-ethynylphenyl)-2,2':6',2"-terpyridine) in the presence of copper(I) iodide and diisopropylamine induced isolation of mononuclear complex cis-Pt(dppm-P,P')(C[triple bond]CPhtpy)2 (1), which can be converted into face-to-face diplatinum(II) species Pt2(mu-dppm)2(C[triple bond]CPhtpy)4 (5) when equivalent dppm is added. Incorporating 1 or 5 to Ln(hfac)3(H2O)2 (Hhfac = hexafluoroacetylacetone) gave PtLn2 (Ln = Nd (2), Eu (3), Yb (4)) or Pt2Ln4 (Ln = Nd (6), Eu (7), Gd (8), Yb (9)) adducts with the lanthanide centers chelated by terdentate terpyridyl in the bridging C[triple bond]CPhtpy. The structures of 1, 6, 7, and 9 were determined by X-ray crystallography. Upon excitation at lambdaex = 360-450 nm (2-4) or 360-500 nm (6-9), where the PtII alkynyl antenna chromophores absorb strongly but the model complexes Ln(hfac)3(HC[triple bond]CPhtpy) lack obvious absorption in this region, these PtLn2 and Pt2Ln4 (Ln = Nd, Eu, Yb) species exhibit band-like lanthanide luminescence that is typical of the corresponding Ln3+ ions, demonstrating unambiguously that efficient Pt --> Ln energy transfer occurs indeed from the PtII alkynyl antenna chromophores to the lanthanide centers across the bridging CCPhtpy with intramolecular Pt...Ln distances being ca. 14.2 A. The Pt --> Ln energy transfer rate (kET) is 6.07 x 10(7) s(-1) for Pt2Nd4 (6) and 2.12 x 10(5) s(-1) for Pt2Yb4 (9) species.

Objective: To establish a ICP-MS method for the determination of heavy metals, including As, Hg, Pb, Cd, in four traditional Chinese medicines., Method: The samples were digested by closed-versel microwave. The four heavy metals were directly analyzed by ICP-MS. Select internal standard element in for the method by which the analyse signal drife is corrected by the signal of another element (internal standard elements) added to both the standard solution and sample., Result: For all of the analyzed heary methals, the correlative coefficient of the calibration curves was over 0.999 2. The recovery rates of the procedure were 97.5%-108.0%, and its RSD was lower than 11.6%., Conclusion: This method was convenient, quick-acquired, accurate and highly sensitive. The method can be used for the quality control of trace elements in traditional Chinese medicines and for the contents determination of traditional Chinese medicines from different habitats and species.