Soft porous coordination polymers (PCPs) have the remarkable ability to recognize similar molecules as a result of their structural dynamics. However, their guest-induced gate-opening behaviors often lead to issues with selectivity and separation efficiency, as co-adsorption is nearly unavoidable. Herein, we report a strategy of a confined-rotational shutter, in which the rotation of pyridyl rings within the confined nanospace of a halogen-bonded coordination framework (NTU-88) creates a maximum aperture of 4.
View Article and Find Full Text PDFBackground: Humans are constantly exposed to various volatile organic compounds (VOCs) because of their widespread sources and characteristic of easy evaporation. Existing evidence regarding the association between VOC exposure and osteoarthritis (OA) risk is limited.
Purpose: This study aimed to investigate the associations between individual urinary VOC metabolites (VOCMs) and the VOCM mixture, representing internal exposure levels of VOCs, with prevalent OA risk and to explore the mediating effect of aging and oxidative stress (OS) in these associations.
Covalent organic frameworks (COFs), as a novel crystalline porous adsorbent, have been attracting significant attention for their synthesis and application exploration due to the advantages of designability, stability, and functionalization. Herein, through increasing the concentration of the acid catalyst, a facile solution-refluxing synthesis method was developed for the preparation of a three-dimensional dynamic COF material, COF-300, with high yields (>90%) and high space−time yields (>28 kg m−3 day−1). This synthesis method not only permits gram-scale synthesis, but also yields products that well maintain porosity and unique guest-dependent dynamic behavior.
View Article and Find Full Text PDFFront Endocrinol (Lausanne)
November 2022
Objective: This study aimed to explore the associations of genetic variants in the semaphorin 3A (SEMA3A) signaling pathway genes, including , , , and with osteoporosis (OP) risk and bone mineral density (BMD) in a Chinese Han older adult population.
Study Design And Method: A two-stage design was adopted. Total of 47.
Limited evidence was found in the associations of volatile organic compound (VOC) exposure with bone health indicators. This study aimed to explore the associations of individual and combined metabolites of VOCs (mVOCs) in urine, a representative of the internal exposure level of VOCs, with bone mineral density (BMD), osteoporosis (OP) and fracture, and potential mediators. Data of the National Health Examination and Nutrition Survey 2005-2006 and 2013-2014 was used.
View Article and Find Full Text PDFBackground: Large-scale detection has great potential to bring benefits for containing the COVID-19 epidemic and supporting the government in reopening economic activities. Evaluating the true regional mobile severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) virus nucleic acid testing capacity is essential to improve the overall fighting performance against this epidemic and maintain economic development. However, such a tool is not available in this issue.
View Article and Find Full Text PDFMethane, as the main component of natural gas, shale gas, and marsh gas, is regarded as an ideal clean energy to replace traditional fossil fuels and reduce carbon emissions. Porous materials with superior methane storage capacities are the key to the wide application of adsorbed natural gas technology in vehicle transportation. In this work, we applied a ligand tailoring strategy to a metal-organic framework (NOTT-101) to fine-tune its pore geometry, which was well characterized by gas and dye sorption measurements.
View Article and Find Full Text PDFBackground: Few studies have explored the association between water intake and mortality risk, and the findings were inconsistent.
Objective: This study aimed to explore the water intake-mortality association, utilizing the data from the National Health and Nutrition Examination Survey (NHANES) and the 2015 public-linked mortality files released by the National Center for Health Statistics.
Methods: We used the diet- and mortality-linked data of a total of 35,463 adults (17,234 men) aged ≥20 years in the NHANESs 1999-2014 to perform a prospective study.
Background & Aims: Existing epidemiological studies explored the associations of circulating vitamins and mortality focusing on individual vitamin effects, and controversial findings were obtained. The joint effects of multiple vitamin co-exposure are worth studying. The study aimed to elucidate the associations of circulating vitamins and the joint effects of these vitamins' co-exposure with all-cause and cause-specific mortality risks.
View Article and Find Full Text PDFThis study aimed to explore the relationships between the common variants of R-spondin/Wnt signaling genes, gut microbiota composition, and osteoporosis (OP) risk in elderly Chinese Han population. Dual-energy X-ray absorptiometry was used to obtain the OP-associated measurements at multiple skeleton sites among all 1,168 participants. Genotyping data was obtained by using the next-generation sequencing in the discovery stage ( = 400, 228 OP patients) and SNPscan technology in the replication stage ( = 768, 356 OP patients).
View Article and Find Full Text PDFEpidemiologic studies focus on combined effects of multiple metals on bone mineral density (BMD) are scarce. Therefore, this study was conducted to examine associations of multiple metals exposure with BMD. Data of adults aged ≥20 years (n = 2545) from the US National Health and Nutrition Examination Survey (NHANES, 2011-2016) were collected and analyzed.
View Article and Find Full Text PDFA solvothermal reaction of Zn(NO) and 4-(1-pyrazol-4-yl)benzoic acid (Hpba) with toluene (Tol) as the template yielded a porous coordination polymer, [Zn(pba)]·0.5Tol, possessing a three-dimensional (3D) fence-like coordination framework based on inclined two-dimensional (2D) fence-like coordination layers. By virtue of the classic deformation mode of the 2D/3D fence structures, the guest-free structure exhibits very large positive thermal expansion of 347 MK and moderate negative thermal expansion of -63/-83 MK, which are remarkably enhanced to new records of 689 and -171/-249 MK, respectively, by inclusion of Tol.
View Article and Find Full Text PDFSolvothermal reactions of 3-(3-methylpyridin-4-yl)benzoic acid (Hmpba) with Mn(NO) or Co(NO) yielded isostructural porous coordination polymers, [Mn(mpba)]·guest (MCF-56, ) and [Co(mpba)]·guest (MCF-57, ), respectively. X-ray diffraction revealed that and possess similar one-dimensional ultramicroporous channels, and guest-free [Mn(mpba)] () and [Co(mpba)] () possess significantly and slightly contracted channels, respectively. Single-component CH/CH adsorption isotherms and computational simulations showed the typical nonporous-to-porous structural transformations for , in which CH exhibits a significantly lower threshold pressure, and the typical small-pore-to-large-pore structural transformations for , in which CH exhibits a slightly lower threshold pressure.
View Article and Find Full Text PDFUnderstanding, controlling, and utilizing the flexibility of adsorbents are of great importance and difficulty. Analogous with conventional solid materials, downsizing to the nanoscale is emerging as a possible strategy for controlling the flexibility of porous coordination polymers (or metal-organic frameworks). We report a unique flexibility controllable by crystal size at the micrometer to submillimeter scale.
View Article and Find Full Text PDFGuest-dependent dynamics having both crystal contraction and expansion upon inclusion of various guests is uncovered in a 3D covalent organic framework (COF) prepared with a facile and scalable method. A molecular-level understanding of how the framework adjusts the node geometry and molecular configuration to perform significant contraction and large amplitude expansion are resolved through synchrotron in-house powder X-ray diffraction (PXRD) and Rietveld refinements. We found that the COF adopts a contracted phase at ambient conditions upon capturing moisture and is also adaptive upon inclusion of organic solvents, which is highlighted by a large crystal expansion (as large as 50% crystallographic volume increment and a 3-fold channel size enlargement).
View Article and Find Full Text PDFThere are great challenges in developing efficient adsorbents to replace the currently used and energy-intensive cryogenic distillation processes for olefin/paraffin separation, owing to the similar physical properties of the two molecules. Here we report an ultramicroporous metal-organic framework [Ca(CO)(HO)], synthesized from calcium nitrate and squaric acid, that possesses rigid one-dimensional channels. These apertures are of a similar size to ethylene molecules, but owing to the size, shape and rigidity of the pores, act as molecular sieves to prevent the transport of ethane.
View Article and Find Full Text PDFACS Appl Mater Interfaces
October 2018
Recently, layered perovskites attracted great attention for its excellent stability and light-emitting property. However, most of them rely on the toxic element lead and their emission quantum yields are generally low. Here, a unique hollow two-dimensional perovskite was developed in which the organic hexamethylene diamines (CHN) strongly coupled with distorted tin bromide anions (SnBr).
View Article and Find Full Text PDFSolvothermal reactions of 3-(4-pyridyl)-benzoic acid (Hpba) with a series of transition metal ions yielded isostructral metal-organic frameworks [M(pba)]·2DMA (MCF-52; M = Ni, Co, Zn, Cd, or mixed Zn/Cd; DMA = ,-dimethylacetamide) possessing two-dimensional fence-like coordination networks based on mononuclear 4-connected metal nodes and 2-connected organic ligands. Variable-temperature single-crystal X-ray diffraction studies of these materials revealed huge positive and negative thermal expansions with |α| > 150 × 10 K, in which the larger metal ions give the larger thermal expansion coefficients, because the increased space not only enhance the ligand vibrational motion and hinged-fence effect, but also allow larger changes of steric hindrance between the layers. In addition, the solid-solution crystal with mixed metal ions further validates the abundant thermal expansion mechanisms of these metal-organic layers.
View Article and Find Full Text PDFPore size is one of the most important parameters of adsorbents, and mesoporous materials have received intense attention for large guests. Here, a series of mesoporous coordination polymers underlying a new framework prototype for fast expansion of pore size is reported and the profound effect of pore size on adsorption heat transformation is demonstrated. Three isostructural honeycomb-like frameworks are designed and synthesized by combining ditopic linear metal oxalate chains and triangular tris-pyridine ligands.
View Article and Find Full Text PDFThe pore size and framework flexibility of hosts are of vital importance for molecular recognition and related applications, but accurate control of these parameters is very challenging. We use the slight difference of metal ion size to achieve continuous hundredth-nanometer pore-size adjustments and drastic flexibility modulations in an ultramicroporous metal-organic framework, giving controllable N adsorption isotherm steps, unprecedented/reversed loading-dependence of H adsorption enthalpy, quadrupole-moment sieving of CH/CO, and an exceptionally high working capacity for CH storage under practical conditions (98 times that of an empty cylinder). single-crystal X-ray diffraction measurements and multilevel computational simulations revealed the importance of pore-surface pockets, which utilize their size and electrostatic potential to smartly recognize the molecular sizes and quadruple moments of gas molecules to control their accessibility to the strongest adsorption sites.
View Article and Find Full Text PDFMesoporous ZnO(-COO)-based metal-organic frameworks (MOFs), including UMCM-1, MOF-205, MUF-7a, and the newly synthesized MOFs, termed ST-1, ST-2, ST-3, and ST-4 (ST = ShanghaiTech University), have been systematically investigated for ultrahigh capacity methane storage. Exceptionally, ST-2 was found to have the highest deliverable capacity of 289 cm/cm (567 mg/g) at 298 K and 5-200 bar, which surpasses all previously reported records held by porous materials. We illustrate that the fine-tuned mesoporosity is critical in further improving the deliverable capacities at ultrahigh pressure.
View Article and Find Full Text PDFLuminescent porous coordination polymers (PCPs) are emerging as attractive oxygen-sensing materials, but they are mostly based on single-wavelength luminometry. Here, we report a special mixed-lanthanide strategy for self-referenced ratiometric oxygen sensing. A series of isostructural, pure-lanthanide, or mixed-lanthanide PCPs, MCF-53(Tb/Eu), were synthesized by solvothermal reactions.
View Article and Find Full Text PDFThrough a modified solvothermal reaction using benzoic acid as an additive, the fcu-type framework [Zr O (OH) (edba) ] (H edba=4,4'-(ethyne-1,2-diyl)dibenzoic acid), an expanded version of UiO-66, is synthesized as high-quality single crystals, which can retain their single-crystallinity after solvent exchange and degas treatments. In situ variable-temperature single-crystal X-ray diffraction measurements show that the guest-free framework exhibits a remarkably large isotropic negative thermal expansion (α=-11.0×10 K ) as a result of the transverse vibrational bending of the long organic ligand.
View Article and Find Full Text PDFBy changing the ligand substituent groups near the open metal sites from hydrophilic to hydrophobic, the guest-induced structural dynamism of a series of isostructural 5-fold interpenetrated MOFs changed from interpenetration reconstitution to simple framework breathing.
View Article and Find Full Text PDFThe dynamic behaviours of host frameworks and guest molecules have received much attention for their great relevance with smart materials, but little has been developed to control or understand the host-guest interplay. Here we show that the confined guest can utilize not only molecular static effects but also bulk dynamic properties to control the host dynamics. By virtue of the three-dimensional hinge-like framework and quasi-discrete ultramicropores, a flexible porous coordination polymer exhibits not only drastic guest-modulation effect of the thermal expansion magnitude (up to 422 × 10(-6) K(-1)) and even the anisotropy but also records positive/negative thermal expansion coefficients of +482/-218 × 10(-6) K(-1).
View Article and Find Full Text PDF© LitMetric 2025. All rights reserved.