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1.
Eur Spine J ; 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38853178

RESUMO

PURPOSE: Subsequent vertebral fracture (SVF) is a severe advent event of percutaneous vertebral augmentation (PVA). However, the incidence and risk factors of SVF following PVA for OVCF in postmenopausal women remain unclear. This research aims to investigative the incidence and risk factors of SVF after PVA for OVCF in postmenopausal women. METHODS: Women who underwent initial PVA for OVCF between August 2019 and December 2021 were reviewed. Univariate logistic regression analysis was performed to identify possible risk factors of SVF, and independent risk factors were determined by multivariate logistic regression. RESULTS: A total of 682 women after menopause were enrolled in the study. Of these women, 100 cases had an SVF after PVA, with the incidence of 14.66%. Univariate logistic regression analysis demonstrated that age (p = 0.001), body mass index (BMI) (p < 0.001), steroid use (p = 0.008), history of previous vertebral fracture (p < 0.001), multiple vertebral fracture (p = 0.033), postoperative wedge angle (p = 0.003), and HU value (p < 0.001) were significantly correlated with SVF following PVA. Furthermore, BMI (OR [95%CI] = 0.892 [0.825 - 0.965]; p = 0.004), steroid use (OR [95%CI] = 3.029 [1.211 - 7.574]; p = 0.018), history of previous vertebral fracture (OR [95%CI] = 1.898 [1.148 - 3.139]; p = 0.013), postoperative wedge angle (OR [95%CI] = 1.036 [1.004 - 1.070]; p = 0.028), and HU value (OR [95%CI] = 0.980 [0.971 - 0.990]; p < 0.001) were identified as independent risk factors of SVF after PVA by multivariate logistic regression analysis. CONCLUSIONS: The incidence of SVF following PVA for OVCF in postmenopausal women was 14.66%. BMI, steroid use, history of previous vertebral fracture, postoperative wedge angle, and HU value were independent risk factors of SVF after PVA for OVCF in postmenopausal women.

2.
Angew Chem Int Ed Engl ; 63(16): e202400496, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38390642

RESUMO

The high-entropy-alloy (HEA) nanoparticles with four, five or more metals significantly can yield the developments of functional materials with excellent performances in various reactions. However, the underlying reaction mechanisms of heterogeneous catalysis for HEA have been rarely investigated, due to their diverse elements and complex compositions. In this study, we successfully synthesized the homogeneously dispersed Ru-Rh-Pd-Pt HEA with adjustable compositions, as the multiple-atom-site catalysts (MASC). In the NOx reduction performance tests, Ru0.4 (Rh0.33Pd0.33Pt0.33)0.6 MASC showed the highest activity, which was significantly improved compared to that of the best monometal Rh, with the light-off temperature decreasing by ca. 50 °C. The Fourier transform infrared measurements revealed that the outstanding activity of Ru-Rh-Pd-Pt MASC was attributable to the well-coupled elementary steps of the CO adsorption, NO adsorption, NO dissociation and O spillover on the Ru, Rh, Rh-Pd and Pt sites, respectively, which explained the first clear reaction mechanism in heterogeneous catalysis for HEA.

3.
Int Wound J ; 2023 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-37852784

RESUMO

The objective of this research is to evaluate the risk of postoperative infection and other risks associated with robotic radical hysterectomy (RRH) compared with laparoscopic radical hysterectomy (LRH). Recent studies on RRH versus LRH have not been conclusive for cervical carcinoma. Our group attempted to use meta-analyses to evaluate the effects of both RRH and LRH on postoperative outcomes in order to make sure that the best operative method was used to prevent wound infections. We looked up Cochrane Library and published databases for this research and found 594 findings. Articles were screened by title and abstract and then carefully examined for inclusion and exclusion criteria. Data extraction was performed independently by two researchers. Comparison studies were used to describe the incidence of wound complications after surgery. The publication bias was assessed using Egger regression correlation analysis. There were six trials eligible for inclusion, of which 491 RRH and 807 LRH. Depending on surgery for cervical carcinoma, it is true that there is a difference in the way that surgery affects the postoperative complications. Our analysis demonstrated that the use of robotic operation can decrease the amount of blood loss during operation as compared with routine laparoscopy (MD, -77.69; 95% CI, -132.08, -23.30; p = 0.005). However, there were no statistical differences in the incidence of postoperative wound infections (OR, 0.54; 95% CI, 0.25, 1.19; p = 0.13) and intraoperative operative time (MD, 13.01; 95% CI, -41.38, 67.41; p = 0.64) among the two procedures. There was no statistically significant difference between these two groups of patients with severe postoperative complications. Unlike other research, the findings of this meta-analysis are not consistent with the findings of the present study, which suggest that robotic operations cannot lower the rate of postoperative wound infections. However, because of the limitations and the retrospective character of the trials covered, these findings should be interpreted with care and more extensive research is required.

4.
ACS Chem Biol ; 18(9): 2063-2072, 2023 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-37671702

RESUMO

The bacterial cell envelope provides a protective barrier that is challenging for small molecules and biomolecules to cross. Given the anionic nature of both Gram-positive and Gram-negative bacterial cell envelopes, negatively charged molecules are particularly difficult to deliver into these organisms. Many strategies have been employed to penetrate bacteria, ranging from reagents such as cell-penetrating peptides, enzymes, and metal-chelating compounds to physical perturbations. While cationic polymers are known antimicrobial agents, polymers that promote the permeabilization of bacterial cells without causing high levels of toxicity and cell lysis have not yet been described. Here, we investigate four polymers that display a cationic poly(2-(dimethylamino)ethyl methacrylate (D) block for the internalization of an anionic adenosine triphosphate (ATP)-based chemical probe into Escherichia coli and Bacillus subtilis. We evaluated two polymer architectures, linear and micellar, to determine how shape and hydrophobicity affect internalization efficiency. We found that, in addition to these reagents successfully promoting probe internalization, the probe-labeled cells were able to continue to grow and divide. The micellar structures in particular were highly effective for the delivery of the negatively charged chemical probe. Finally, we demonstrated that these cationic polymers could act as general permeabilization reagents, promoting the entry of other molecules, such as antibiotics.


Assuntos
Trifosfato de Adenosina , Antibacterianos , Antibacterianos/farmacologia , Bacillus subtilis , Cátions , Morte Celular , Escherichia coli
5.
Medicine (Baltimore) ; 102(37): e35259, 2023 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-37713884

RESUMO

Chondrosarcoma is the second largest bone malignancy after osteosarcoma and mainly affects middle-aged adults, where patients with distant metastasis (DM) often have a poor prognosis. Although nomograms have been widely used to predict distant tumor metastases, there is a lack of large-scale data studies for the diagnostic evaluation of DM in chondrosarcoma. Data on patients diagnosed with chondrosarcoma from 2004 to 2015 were obtained from the Surveillance, Epidemiology, and End Results database. Independent risk factors for having DM from chondrosarcoma were screened using univariate and multivariate logistics regression analysis. A nomogram was created to predict the probability of DM from the screened independent risk factors. The nomogram was then validated using receiver operating characteristic curves and calibration curves. A total of 1870 chondrosarcoma patients were included in the study after data screening, of which 157 patients (8.40%) had DM at the time of diagnosis. Univariate and multivariate logistic regression analysis screened four independent risk factors, including grade, tumor number, T stage, and N stage. receiver operating characteristic curves and calibration curves showed good accuracy of the nomogram in both training and validation sets. The current study screened for independent risk factors for DM from chondrosarcoma, which will help clinicians evaluate patients.


Assuntos
Neoplasias Ósseas , Condrossarcoma , Segunda Neoplasia Primária , Osteossarcoma , Adulto , Pessoa de Meia-Idade , Humanos , Condrossarcoma/epidemiologia , Pesquisa , Calibragem , Fatores de Risco , Neoplasias Ósseas/epidemiologia
6.
Genet Res (Camb) ; 2023: 5574636, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36960385

RESUMO

Osteoarthritis (OA) is a chronic musculoskeletal disease affecting approximately 500 million people worldwide. Globally, OA is one of the most common and leading causes of disability. Several genetic factors are involved in OA, including inherited genes, genetic susceptibility, and genetic predisposition. As the pathogenesis of OA is unknown, there are almost no effective treatments available to prevent the onset or progression of the disease. In recent years, many researchers focused on bioinformatics analysis to explore new biomarkers for the diagnosis, treatment, and prognosis of human diseases. In this work, we obtain the traditional RNA sequencing data of OA patients from the GEO database. By performing the differentially expressed analysis, we successfully obtain the genes that are closely associated with the OA. In addition, the Venn diagram was applied to evaluate the genes that are involved in OA and immune-related genes. The protein-protein interaction analysis was further conducted to explore the hub genes. The single-cell RNA sequencing analysis was used to evaluate the expression distribution of the MMP, VEGFA, SPI1, and IRF8 in synovial tissues of patients with osteoarthritis. Finally, the GSVA enrichment analysis discovered the potential pathways involved in OA patients. Our analysis provides a new direction for the exploration of the process of OA patients. In addition, VEGFA may be considered a promising biomarker in OA.


Assuntos
Perfilação da Expressão Gênica , Osteoartrite , Humanos , Osteoartrite/diagnóstico , Osteoartrite/genética , Osteoartrite/terapia , Biomarcadores , Imunoterapia , Análise de Sequência de RNA , Biologia Computacional , Redes Reguladoras de Genes
7.
Science ; 379(6631): 457-461, 2023 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-36730415

RESUMO

Extreme wildfires threaten human lives, air quality, and ecosystems. Meteorology plays a vital role in wildfire behaviors, and the links between wildfires and climate have been widely studied. However, it is not fully clear how fire-weather feedback affects short-term wildfire variability, which undermines our ability to mitigate fire disasters. Here, we show the primacy of synoptic-scale feedback in driving extreme fires in Mediterranean and monsoon climate regimes in the West Coast of the United States and Southeastern Asia. We found that radiative effects of smoke aerosols can modify near-surface wind, air dryness, and rainfall and thus worsen air pollution by enhancing fire emissions and weakening dispersion. The intricate interactions among wildfires, smoke, and weather form a positive feedback loop that substantially increases air pollution exposure.

8.
Quant Imaging Med Surg ; 13(2): 1036-1047, 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36819268

RESUMO

Background: Measuring the Hounsfield units (HU) of the vertebrae may yield diagnostic information for fracture risk. This study aimed to measure HU of vertebrae in percutaneous kyphoplasty (PKP) patients using computed tomography (CT) imaging to determine the HU measurements threshold for adjacent vertebral fracture and to assess the relationship between HU measurements and the risk of adjacent vertebral fracture. Methods: A retrospective study was conducted on consecutive patients who underwent PKP between January 2019 and October 2021 in the China-Japan Union Hospital of Jilin University. The HU of the vertebra was measured on the reconstructed CT images by 2 independent spine surgeons. The HU measurements of adjacent vertebrae and the ratio of HU measurements between the surgical vertebra and adjacent vertebrae were statistically analyzed to determine the best critical value and evaluate the prediction effectiveness and accuracy of the best critical value. Results: A total of 105 patients were identified with complete imaging and follow-up information. Of these, 47 patients (44.8%) had evidence of an adjacent vertebral fracture on follow-up imaging. The mean HU measurements of the fractured adjacent vertebra were significantly different from the mean HU measurements of the unfractured adjacent vertebra (50.94±20.59 vs. 81.74±18.97 HU; P<0.001). There was a significant difference in the ratio of HU measurements between the surgical vertebra and the fractured adjacent vertebra and between the surgical vertebra and the unfractured adjacent vertebra (26.34±17.52 vs. 14.53±9.40; P<0.001). Interactive scatter plots and receiver operating characteristic (ROC) curve showed that a HU measurement of 66.9 and a HU measurements ratio of 15.18 were the best thresholds for predicting the risk of fracture of adjacent vertebrae after PKP surgery, with an area under the curve (AUC) of 0.901 [95% confidence interval (CI): 0.822-0.953; P<0.001] and 0.874 (95% CI: 0.790-0.934; P<0.001), respectively. The prediction accuracy was 90.4% and 84.0%, respectively. Conclusions: A low mean HU measurements of adjacent vertebrae or a high ratio of the mean HU measurements of the operated vertebrae to the adjacent vertebrae are risk factors for the vulnerability of adjacent vertebrae to fracture. The risk of fracture in the adjacent vertebrae after PKP can be predicted by measuring HU.

9.
Medicine (Baltimore) ; 101(46): e31544, 2022 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-36401370

RESUMO

BACKGROUND: High viscosity cement (HVC) and low viscosity cement (LVC) have been used to treat osteoporotic vertebral compression fractures (OVCFs). Our study was to assess the safety and efficacy of HVC and LVC in treating OVCFs. METHODS: We searched the electronic database for randomized controlled trials of HVC and LVC to treat OVCFs. Random-effects model was performed to pool the outcomes about operation time, visual analogue scale (VAS), bone cement injection volume, oswestry disability index (ODI), bone cement leakage and adjacent vertebral fractures. RESULTS: Twelve randomized trials were included in the meta-analysis. The 2 groups had similar changes in terms of bone cement injection volume, ODI and adjacent vertebral fractures. The HVC group showed shorter operation time and better VAS score improvement. The bone cement leakage rate of the HVC group was significantly better than LVC group (P < .00001).According to the location of bone cement leakage, in the leakages of the veins (P < .00001), the intervertebral disc (P < .00001), the paravertebral area (P = .003) and the intraspinal space (P = .03), the HVC group were significantly better than the LVC group. CONCLUSIONS: In terms of bone cement injection volume, ODI and adjacent vertebral fractures, the 2 group are equivalent. HVC had a shorter operation time, lower bone cement leakage rate and better VAS score improvement, compared with LVC.


Assuntos
Fraturas por Compressão , Fraturas da Coluna Vertebral , Vertebroplastia , Humanos , Fraturas por Compressão/cirurgia , Fraturas da Coluna Vertebral/cirurgia , Cimentos Ósseos/uso terapêutico , Viscosidade , Ensaios Clínicos Controlados Aleatórios como Assunto , Materiais Dentários
10.
Nat Commun ; 13(1): 6405, 2022 10 27.
Artigo em Inglês | MEDLINE | ID: mdl-36302779

RESUMO

Resistance artery vasodilation in response to hypoxia is essential for matching tissue oxygen and demand. In hypoxia, erythrocytic hemoglobin tetramers produce nitric oxide through nitrite reduction. We hypothesized that the alpha subunit of hemoglobin expressed in endothelium also facilitates nitrite reduction proximal to smooth muscle. Here, we create two mouse strains to test this: an endothelial-specific alpha globin knockout (EC Hba1Δ/Δ) and another with an alpha globin allele mutated to prevent alpha globin's inhibitory interaction with endothelial nitric oxide synthase (Hba1WT/Δ36-39). The EC Hba1Δ/Δ mice had significantly decreased exercise capacity and intracellular nitrite consumption in hypoxic conditions, an effect absent in Hba1WT/Δ36-39 mice. Hypoxia-induced vasodilation is significantly decreased in arteries from EC Hba1Δ/Δ, but not Hba1WT/Δ36-39 mice. Hypoxia also does not lower blood pressure in EC Hba1Δ/Δ mice. We conclude the presence of alpha globin in resistance artery endothelium acts as a nitrite reductase providing local nitric oxide in response to hypoxia.


Assuntos
Óxido Nítrico , Nitrito Redutases , Camundongos , Animais , Nitrito Redutases/genética , Nitrito Redutases/farmacologia , Óxido Nítrico/farmacologia , Nitritos , alfa-Globinas/genética , Hipóxia , Endotélio Vascular , Hemoglobinas/genética , Vasodilatação/fisiologia
11.
Chem Commun (Camb) ; 58(80): 11296-11299, 2022 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-36124898

RESUMO

Fe2O3 reduction to Fe with carbon requires a high temperature of 1200 °C in a blast furnace process. We have discovered a novel low-temperature reduction route from γ-phase Fe2O3 to Fe with carbon. The reduction temperature was 430 °C, which is the lowest recorded up to now.


Assuntos
Carbono , Compostos Férricos , Temperatura
12.
Front Bioeng Biotechnol ; 10: 891765, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35910014

RESUMO

At present, bone-based products are abundant, and the main sources are bovine bone and pig bone, but there are few studies on the development of deer bone as a bone repair material. Deer bone has important osteogenic effects in the theory of traditional Chinese medicine. It is rich in protein, ossein, and a variety of trace elements, with the effect of strengthening tendons and bones. Nanomaterials and their application in the repair of bone defects have become a research hotspot in bone tissue engineering. In this study, nano-deer bone meal (nBM), nano-calcined deer bone meal, and nano-demineralized bone matrix were successfully prepared. It was found that the Ca/P ratio in deer bone was significantly higher than that in cow bone and human bone tissue, and deer bone contained beneficial trace elements, such as potassium, iron, selenium, and zinc, which were not found in cow bone. The three kinds of deer bone powders prepared in this study had good biocompatibility and met the implantation standards of medical biomaterials. Cell function studies showed that compared with other bone powders, due to the presence of organic active ingredients and inorganic calcium and phosphate salts, nBM had excellent performance in the proliferation, adhesion, migration, and differentiation of bone marrow mesenchymal stem cells. These findings indicate that nBM can be used as a potential osteoinductive active nanomaterial to enhance bone tissue engineering scaffolds with certain application prospects.

13.
Pain Res Manag ; 2022: 3458056, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35711611

RESUMO

Background: The enhanced recovery after surgery (ERAS) program is aimed to shorten patients' recovery process and improve clinical outcomes. This study aimed to compare the outcomes between the ERAS program and the traditional pathway among patients with ankle fracture and distal radius fracture. Methods: This is a multicenter prospective clinical controlled study consisting of 323 consecutive adults with ankle fracture from 12 centers and 323 consecutive adults with distal radial fracture from 13 centers scheduled for open reduction and internal fixation between January 2017 and December 2018. According to the perioperative protocol, patients were divided into two groups: the ERAS group and the traditional group. The primary outcome was the patients' satisfaction of the whole treatment on discharge and at 6 months postoperatively. The secondary outcomes include delapsed time between admission and surgery, length of hospital stay, postoperative complications, functional score, and the MOS item short form health survey-36. Results: Data describing 772 patients with ankle fracture and 658 patients with distal radius fracture were collected, of which 323 patients with ankle fracture and 323 patients with distal radial fracture were included for analysis. The patients in the ERAS group showed higher satisfaction levels on discharge and at 6 months postoperatively than in the traditional group (P < 0.001). In the subgroup analysis, patients with distal radial fracture in the ERAS group were more satisfied with the treatment (P=0.001). Furthermore, patients with ankle fracture had less time in bed (P < 0.001) and shorter hospital stay (P < 0.001) and patients with distal radial fracture received surgery quickly after being admitted into the ward in the ERAS group than in the traditional group (P=0.001). Conclusions: Perioperative protocol based on the ERAS program was associated with high satisfaction levels, less time in bed, and short hospital stay without increased complication rate and decreased functional outcomes.


Assuntos
Fraturas do Tornozelo , Recuperação Pós-Cirúrgica Melhorada , Fraturas do Rádio , Adulto , Fraturas do Tornozelo/cirurgia , Humanos , Tempo de Internação , Estudos Prospectivos , Fraturas do Rádio/cirurgia , Resultado do Tratamento
14.
Dalton Trans ; 51(13): 5203-5207, 2022 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-35275158

RESUMO

Designs and developments of proton conductors are highly important in chemistry and energy fields. In this study, a novel metal-organic framework H2DAB-MgNi(ox)3 was synthesized. X-ray powder diffraction, scanning transmission electron microscopy, and scanning transmission electron microscopy-energy-dispersive X-ray mapping measurements demonstrated that the H2DAB-MgNi(ox)3 had a solid-solution structure, with the homogeneous distribution of Mg and Ni elements. The proton conductivity of H2DAB-MgNi(ox)3 was enhanced from that of H2DAB-Ni2(ox)3 at 95% relative humidity by Mg substitution.

15.
Nanoscale ; 14(14): 5482-5487, 2022 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-35323835

RESUMO

This study has established a three-solvent methodology for separating nanomaterials, such as monometallic nanoparticles, miscible and immiscible nanoalloys. After systematically investigating the separation methods in two-solvent and three-solvent systems, a three-solvent theoretical model has been proposed to thoroughly reveal the centrifugation mechanism of colloidal particles. PVP plays an important role in the formation of emulsion droplets as the key factor for separation. Based on the three-solvent model, a novel solvent system has been discovered, with low-toxicity solvents and high separation efficiency. This study can open a new path for the separation of colloidal particles in both research and industrial fields and further promote the development of functional nanomaterials in greener pathways.

16.
Angew Chem Int Ed Engl ; 61(23): e202202588, 2022 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-35302275

RESUMO

This study provided an effective strategy to construct dual-atom sites by solid-solution alloying. A slow synthesis methodology was established for the solid-solution preparations as dual-atom-site catalysts. The atomic-level homogeneous Pdx Rh1-x dual-atom-site catalysts were successfully synthesized over the whole composition range, as evidenced by X-ray powder diffraction and scanning transmission electron microscope energy-dispersive X-ray spectroscopy mapping measurements. The challenging morphology formation in the immiscible alloys was achieved by an energy-controlling process as the octahedral Rh-rich alloys. The Pd0.3 Rh0.7 dual-atom-site catalyst had unique surface states to activate the key reactants of CO and NO in the complex three-way catalytic reactions, and it performed significantly better than pure Rh.

17.
Sci Adv ; 8(2): eabl6166, 2022 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-35030017

RESUMO

Ozone pollution that threatens human health and the ecosystem is a global environmental challenge. In megacities, ozone pollution has long been mainly attributed to anthropogenic sources. However, the processes and mechanisms of cross-regional transport of ozone and its precursors under interactions between mixed sources remain unclear. Here, we show that Northwest Pacific typhoons could intensify the chemical interactions between anthropogenic and biogenic emissions, resulting in extreme ozone pollution in two main city clusters in China. By integrating field and satellite observations together with model simulations, we show that biogenic emission and cross-regional ozone transport are greatly enhanced by approaching typhoons, with the increments reaching up to 78.0 and 22.5%, respectively. Ozone formation efficiency has more than doubled because of abundant precursors and active photochemistry. This study highlights the importance of natural emissions in areas with intensive human activity, which needs to be considered in future air pollution control in China.

18.
Inorg Chem ; 60(21): 16558-16569, 2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34668700

RESUMO

Doping chemistry has become one of the most effective means of tuning materials' properties for diverse applications. In particular for scheelite-type CaWO4, high-oxidation-state doping is extremely important, since one may expand the scheelite family and further create prospective candidates for novel applications and/or useful spectral signatures for nuclear forensics. However, the chemistry associated with high-valence doping in scheelite-type CaWO4 is far from understanding. In this work, a series of scheelite-based materials (Ca1-x-y-zEuxKy□z)WO4 (□ represents the cation vacancy of the Ca2+ site) were synthesized by hydrothermal conditions and solid-state methods and comparatively studied. For the bulk prepared by the solid-state method, occupation of high-oxidation-state Eu3+ at the Ca2+ sites of CaWO4 is followed by doping of the low-oxidation-state K+ at a nearly equivalent molar amount. The Eu3+ local symmetry is thus varied from the original S4 point group symmetry to C2v point group symmetry. Surprisingly different from the cases in bulk, for the nanoscale counterparts prepared by hydrothermal conditions, the high-oxidation-state Eu3+ was incorporated in CaWO4 at two distinct sites, and its amount is higher than that of the low-oxidation-state K+ even though KOH was used as a mineralizer, creating a certain amount of cation vacancies. Consequently, an apparent split emission of 5D0 → 7F0 was first demonstrated for (Ca1-x-y-zEuxKy□z)WO4. The doping chemistry of high oxidation states uncovered in this work not only provides an explanation for the commonly observed spectral changes in rare-earth-ion-modified scheelite structures, but also points out an advanced direction that can guide the design and synthesis of novel functional oxides by solution chemistry routes.

19.
Front Chem ; 9: 706942, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34414161

RESUMO

The host-guest chemistry of metal-organic frameworks (MOFs) has been attracting increasing attention owing to the outstanding properties derived from MOFs-guests combinations. However, there are large difficulties involved in the syntheses of the host-guest MOF systems with air-sensitive metal complexes. In addition, the behaviors on host-guest interactions in the above systems at high temperature are not clear. This study reported the synthetic methods for host-guest systems of metal-organic framework and air-sensitive metal complexes via a developed chemical vapor infiltration process. With the synchrotron X-ray powder diffraction (XRPD) measurements and Fourier Transform infrared spectroscopy (FTIR), the successful loadings of Fe(CO)5 in HKUST-1 and NH2-MIL-101(Al) have been confirmed. At high temperatures, the structural and chemical componential changes were investigated in detail by XRPD and FTIR measurements. HKUST-1 was proven to have strong interaction with Fe(CO)5 and resulted in a heavy loading amount of 63.1 wt%, but too strong an interaction led to deformation of HKUST-1 sub-unit under heating conditions. NH2-MIL-101(Al), meanwhile, has a weaker interaction and is chemically inert to Fe(CO)5 at high temperatures.

20.
Inorg Chem ; 60(14): 10830-10836, 2021 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-34170683

RESUMO

Loading air-sensitive guest molecules inside polycrystalline metal-organic framework (MOF) hosts is currently a challenging process. In this study, the air-sensitive guest molecule magnesocene (MgCp2) was loaded into two porous MOF hosts, polycrystalline Ni-MOF-74 and NH2-MIL-101(Al), using a gas-phase infiltration process. X-ray powder diffraction, Fourier transform infrared spectroscopy, scanning transmission electron microscopy, and scanning transmission electron microscopy-energy-dispersive X-ray mapping measurements demonstrated that MgCp2 was successfully loaded inside the three-dimensional pores of NH2-MIL-101(Al) with a maximum loading of 43.1 wt %. MgCp2 was found to cover the outside of Ni-MOF-74 owing to the small one-dimensional channels.

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