Nitro-Decorated Microporous Covalent Organic Framework (TpPa-NO2) for Selective Separation of C2H4 from a C2H2/C2H4/CO2 Mixture and CO2 Capture.

A nitro-decorated microporous covalent organic framework, TpPa-NO2, has been synthesized in a gram scale with a one-pot reaction. It can effectively selectively separate C2H4 from a C2H2/C2H4/CO2 mixture and capture CO2 from CO2/N2 based on ideal adsorption solution theory calculations and transient breakthrough experiments. Theoretical calculations illustrated that the hydrogen atoms of imine bonds, carbonyl oxygen, and nitro group show high affinity toward C2H2 and CO2, playing vital roles in efficient separation.

Development and external validation of models to predict acute respiratory distress syndrome related to severe acute pancreatitis.

BACKGROUND: Acute respiratory distress syndrome (ARDS) is a major cause of death in patients with severe acute pancreatitis (SAP). Although a series of prediction models have been developed for early identification of such patients, the majority are complicated or lack validation. A simpler and more credible model is required for clinical practice. AIM: To develop and validate a predictive model for SAP related ARDS. METHODS: Patients diagnosed with AP from four hospitals located at different regions of China were retrospectively grouped into derivation and validation cohorts. Statistically significant variables were identified using the least absolute shrinkage and selection operator regression method. Predictive models with nomograms were further built using multiple logistic regression analysis with these picked predictors. The discriminatory power of new models was compared with some common models. The performance of calibration ability and clinical utility of the predictive models were evaluated. RESULTS: Out of 597 patients with AP, 139 were diagnosed with SAP (80 in derivation cohort and 59 in validation cohort) and 99 with ARDS (62 in derivation cohort and 37 in validation cohort). Four identical variables were identified as independent risk factors for both SAP and ARDS: heart rate [odds ratio (OR) = 1.05; 95%CI: 1.04-1.07; P < 0.001; OR = 1.05, 95%CI: 1.03-1.07, P < 0.001], respiratory rate (OR = 1.08, 95%CI: 1.0-1.17, P = 0.047; OR = 1.10, 95%CI: 1.02-1.19, P = 0.014), serum calcium concentration (OR = 0.26, 95%CI: 0.09-0.73, P = 0.011; OR = 0.17, 95%CI: 0.06-0.48, P = 0.001) and blood urea nitrogen (OR = 1.15, 95%CI: 1.09-1.23, P < 0.001; OR = 1.12, 95%CI: 1.05-1.19, P < 0.001). The area under receiver operating characteristic curve was 0.879 (95%CI: 0.830-0.928) and 0.898 (95%CI: 0.848-0.949) for SAP prediction in derivation and validation cohorts, respectively. This value was 0.892 (95%CI: 0.843-0.941) and 0.833 (95%CI: 0.754-0.912) for ARDS prediction, respectively. The discriminatory power of our models was improved compared with that of other widely used models and the calibration ability and clinical utility of the prediction models performed adequately. CONCLUSION: The present study constructed and validated a simple and accurate predictive model for SAP-related ARDS in patients with AP.

High Water Adsorption MOFs with Optimized Pore-Nanospaces for Autonomous Indoor Humidity Control and Pollutants Removal.

The indoor air quality is of prime importance for human daily life and health, for which the adsorbents like zeolites and silica-gels are widely used for air dehumidification and harmful gases capture. Herein, we develop a pore-nanospace post-engineering strategy to optimize the hydrophilicity, water-uptake capacity and air-purifying ability of metal-organic frameworks (MOFs) with long-term stability, offering an ideal candidate with autonomous multi-functionality of moisture control and pollutants sequestration. Through variant tuning of organic-linkers carrying hydrophobic and hydrophilic groups in the pore-nanospaces of prototypical UiO-67, a moderately hydrophilic MOF (UiO-67-4Me-NH2 -38 %) with high thermal, hydrolytic and acid-base stability is screened out, featuring S-shaped water sorption isotherms exactly located in the recommended comfortable and healthy ranges of relative humidity for indoor ventilation (45 %-65 % RH) and adverse health effects minimization (40-60 % RH). Its exceptional attributes of water-uptake working capacity/efficiency, contaminants removal, recyclability and regeneration promise a great potential in confined indoor environment application.

Enhancing Photocatalytic Hydrogen Production via the Construction of Robust Multivariate Ti-MOF/COF Composites.

Titanium metal-organic frameworks (Ti-MOFs), as an appealing type of artificial photocatalyst, have shown great potential in the field of solar energy conversion due to their well-studied photoredox activity (similar to TiO2 ) and good optical responsiveness of linkers, which serve as the antenna to absorb visible-light. Although much effort has been dedicated to developing Ti-MOFs with high photocatalytic activity, their solar energy conversion performances are still poor. Herein, we have implemented a covalent-integration strategy to construct a series of multivariate Ti-MOF/COF hybrid materials PdTCPP⊂PCN-415(NH2 )/TpPa (composites 1, 2, and 3), featuring excellent visible-light utilization, a suitable band gap, and high surface area for photocatalytic H2 production. Notably, the resulting composites demonstrated remarkably enhanced visible-light-driven photocatalytic H2 evolution performance, especially for the composite 2 with a maximum H2 evolution rate of 13.98 mmol g-1 h-1 (turnover frequency (TOF)=227 h-1 ), which is much higher than that of PdTCPP⊂PCN-415(NH2 ) (0.21 mmol g-1 h-1 ) and TpPa (6.51 mmol g-1 h-1 ). Our work thereby suggests a new approach to highly efficient photocatalysts for H2 evolution and beyond.

Catalysis through Dynamic Spacer Installation of Multivariate Functionalities in Metal-Organic Frameworks.

We demonstrate herein a facile strategy to engineer versatile catalytically active coordination interspace in the same primitive metal-organic framework (MOF) for variable heterogeneous catalysis. Different functional ligands can be reversibly inserted into and removed from proto-LIFM-28 individually or successively to bring in single or binary catalytic sites for specific reactions and switch the parent MOF to multipurpose catalysts. Alcohol-oxidation, Knoevenagel-condensation, click, acetal, and Baylis-Hillman reactions are achievable through simple exchange of a single catalytic spacer, while sequential or stepwise reactions are designable via selective combination of two catalytic spacers with different functionalities, thus making proto-LIFM-28 a multivariate MOF for multiuse and economic catalysis.

Functionalizing a Metal-Organic Framework by a Photoassisted Multicomponent Postsynthetic Modification Approach Showing Highly Effective Hg(II) Removal.

We present here the first use of a photoassisted multicomponent postsynthetic modification method to anchor a ZIF-90 scaffold with a pyrimidinethione fragment. The resultant materials, namely, ZIF-90-THP and ZIF-90-THF, show ultrahigh Hg(II) adsorption capacity values of up to 596 and 403 mg/g, respectively, relative to the pristine ZIF-90, which just affords a corresponding value of 47 mg/g, suggesting a 12.7- and 8.6-fold enhancement in the Hg(II) adsorption capacity.

The MOF+ Technique: A Potential Multifunctional Platform.

Pores are the most ubiquitous moieties in metal-organic frameworks (MOFs). Based on pore, the MOFs can thus communicate with various guest molecules, leading to many important applications such as storage, separation, and catalysis. However, its abundant surface, presenting another basic component, is often ignored. This is primarily due to the intrinsic stability of surface atoms of MOFs towards external surroundings, or an opposite status of badly destroying the structure of MOFs. In this concept article, we present a novel MOF+ technique, which is a complete surface technique. The design, mechanism, applications, challenges and perspectives are discussed in detail.

The MOF+ Technique: A Significant Synergic Effect Enables High Performance Chromate Removal.

A significant synergic effect between a metal-organic framework (MOF) and Fe2 SO4 , the so-called MOF+ technique, is exploited for the first time to remove toxic chromate from aqueous solutions. The results show that relative to the pristine MOF samples (no detectable chromate removal), the MOF+ method enables super performance, giving a 796 Cr mg g-1 adsorption capacity. The value is almost eight-fold higher than the best value of established MOF adsorbents, and the highest value of all reported porous adsorbents for such use. The adsorption mechanism, unlike the anion-exchange process that dominates chromate removal in all other MOF adsorbents, as unveiled by X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), and transmission electron microscopy (TEM), is due to the surface formation of Fe0.75 Cr0.25 (OH)3 nanospheres on the MOF samples.

MOF catalysis of Fe(II)-to-Fe(III) reaction for an ultrafast and one-step generation of the Fe2O3@MOF composite and uranium(vi) reduction by iron(ii) under ambient conditions.

Herein, we demonstrate that Zn-MOF-74 enables the ultrafast and one-step generation of the Fe2O3@MOF composite once Zn-MOF-74 contacts with FeSO4 solution. This unique reaction can be further applied in catalysis of U(vi) reduction by Fe(ii) under ambient conditions. The results provide a highly renovated strategy for U(vi) reduction by Fe(ii) just under ambient conditions, which completely subvert all established methods about U(vi) reduction by Fe(ii) in which O2- and CO2-free conditions are absolutely required.