Supramolecular Entanglement in a Hydrogen-Bonded Organic Framework Enables Flexible-Robust Porosity for Highly Efficient Purification of Natural Gas.

The development of porous materials with flexible-robust characteristics shows some unique advantages to target high performance for gas separation, but remains a daunting challenge to achieve so far. Herein, we report a carboxyl-based hydrogen-bonded organic framework (ZJU-HOF-8a) with flexible-robust porosity for efficient purification of natural gas. ZJU-HOF-8a features a four-fold interpenetrated structure with dia topology, wherein abundant supramolecular entanglements are formed between the adjacent subnetworks through weak intermolecular hydrogen bonds. This structural configuration could stabilize the whole framework to establish the permanent porosity, but also enable the framework to show some flexibility (so-called flexible-robust framework). The flexible-robust porosity of ZJU-HOF-8a was confirmed by gas sorption isotherms and SCXRD studies, showing that the flexible pore pockets can be opened by C3H8 and n-C4H10 rather by C2H6 and CH4. This leads to notably higher C3H8 and n-C4H10 uptakes with enhanced selectivities than C2H6 over CH4, affording one of the highest n-C4H10/CH4 selectivities. The gas-loaded single-crystal structures coupled with theoretical simulations reveal that the loading of n-C4H10 can induce an obvious framework expansion along with pore-pocket opening to improve n-C4H10 uptake and selectivity, while not for C2H6 adsorption. This work suggests an effective strategy of designing flexible-robust HOFs for improving gas separation properties.

Incorporation of multiple supramolecular binding sites into a robust MOF for benchmark one-step ethylene purification.

One-step adsorption separation of C2H4 from ternary C2 hydrocarbon mixtures remains an important and challenging goal for petrochemical industry. Current physisorbents either suffer from unsatisfied separation performance, poor stability, or are difficult to scale up. Herein, we report a strategy of constructing multiple supramolecular binding sites in a robust and scalable MOF (Al-PyDC) for highly efficient one-step C2H4 purification from ternary mixtures. Owing to suitable pore confinement with multiple supramolecular binding sites, Al-PyDC exhibits one of the highest C2H2 and C2H6 uptakes and selectivities over C2H4 at ambient conditions. The gas binding sites have been visualized by single-crystal X-ray diffraction studies, unveiling that the low-polarity pore surfaces with abundant electronegative N/O sites provide stronger multiple supramolecular interactions with C2H2 and C2H6 over C2H4. Breakthrough experiments showed that polymer-grade C2H4 can be separated from ternary mixtures with a maximum productivity of 1.61 mmol g-1. This material can be prepared from two simple reagents using a green synthesis method with water as the sole solvent, and its synthesis can be easily scaled to multikilogram batches. Al-PyDC achieves an effective combination of benchmark separation performance, high stability/recyclability, green synthesis and easy scalability to address major challenges for industrial one-step C2H4 purification.

Programmed fluorine binding engineering in anion-pillared metal-organic framework for record trace acetylene capture from ethylene.

Porous physisorbents are attractive candidates for selective capture of trace gas or volatile compounds due to their low energy footprints. However, many physisorbents suffer from insufficient sorbate-sorbent interactions, resulting in low uptake or inadequate selectivity when gases are present at trace levels. Here, we report a strategy of programmed fluorine binding engineering in anion-pillared metal-organic frameworks to maximize C2H2 binding affinity for benchmark trace C2H2 capture from C2H4. A robust material (ZJU-300a) was elaborately designed to provide multiple-site fluorine binding model, resulting in an ultrastrong C2H2 binding affinity. ZJU-300a exhibits a record-high C2H2 uptake of 3.23 millimoles per gram (at 0.01 bar and 296 kelvin) and one of the highest C2H2/C2H4 selectivity (1672). The adsorption binding of C2H2 and C2H4 was visualized by gas-loaded ZJU-300a structures. The separation capacity was confirmed by breakthrough experiments for 1/99 C2H2/C2H4 mixtures, affording the maximal dynamic selectivity (264) and C2H4 productivity of 436.7 millimoles per gram.

Scalable Green Synthesis of Robust Ultra-Microporous Hofmann Clathrate Material with Record C3 H6 Storage Density for Efficient C3 H6 /C3 H8 Separation.

Developing porous materials for C3 H6 /C3 H8 separation faces the challenge of merging excellent separation performance with high stability and easy scalability of synthesis. Herein, we report a robust Hofmann clathrate material (ZJU-75a), featuring high-density strong binding sites to achieve all the above requirements. ZJU-75a adsorbs large amount of C3 H6 with a record high storage density of 0.818 g mL-1 , and concurrently shows high C3 H6 /C3 H8 selectivity (54.2) at 296 K and 1 bar. Single-crystal structure analysis unveil that the high-density binding sites in ZJU-75a not only provide much stronger interactions with C3 H6 but also enable the dense packing of C3 H6 . Breakthrough experiments on gas mixtures afford both high separation factor of 14.7 and large C3 H6 uptake (2.79 mmol g-1 ). This material is highly stable and can be easily produced at kilogram-scale using a green synthesis method, making it as a benchmark material to address major challenges for industrial C3 H6 /C3 H8 separation.

[Factors Influencing the efficacy of Plasma Exchange in the Treatment of Immune Thrombocytopenic Purpura].

OBJECTIVE: To observe the efficacy of plasma exchange in the treatment of patients with immune thrombocytopenic purpura (ITP), and to analyze the factors influencing the efficacy of plasma exchange in the treatment of ITP. METHODS: The medical records of 39 ITP patients who were treated effectively by plasma exchange in Huai'an First People's Hospital from January 2013 to January 2021 were retrospectively analyzed, and they were set as the effective group. In addition, the medical records of 39 ITP patients who were treated ineffective by plasma exchange during the same period in our hospital were collected, and they were set as the ineffective group. The general data such as sex and age of patients and laboratory indicators on admission were collected and recorded. The possible influencing factors were included, and Logistic regression analysis was used to examine the influencing factors of efficacy of plasma exchange in the treatment of ITP. RESULTS: The serum levels of IL-6, IL-18 and B lymphocyte activating factor (BAFF) on admission in the ineffective group were significantly higher than those in the effective group, and the proportions of Helicobacter pylori (HP) infection and splenomegaly were significantly higher than those in the effective group (P<0.05). There was no statistical significantly difference in sex, age and other data between the two groups (P>0.05). After single factor analysis, multiple regression model was established, which showed that splenomegaly, HP infection and the over expression of serum IL-6, IL-18 and BAFF on admission might be the influencing factors of ineffective treatment of ITP by plasma exchange (OR>1, P<0.05). CONCLUSION: The over expression of serum IL-6, IL-18, BAFF, splenomegaly and HP infection on admission may be the influencing factors resulting in the ineffective treatment of plasma exchange in ITP.

Engineering Supramolecular Binding Sites in a Chemically Stable Metal-Organic Framework for Simultaneous High C2 H2 Storage and Separation.

Developing porous materials to overcome the trade-off between adsorption capacity and selectivity for C2 H2 /CO2 separation remains a challenge. Herein, we report a stable HKUST-1-like MOF (ZJU-50a), featuring large cages decorated with high density of supramolecular binding sites to achieve both high C2 H2 storage and selectivity. ZJU-50a exhibits one of the highest C2 H2 storage capacity (192 cm3 g-1 ) and concurrently high C2 H2 /CO2 selectivity (12) at 298 K and 1 bar. Single-crystal X-ray diffraction studies on gas-loaded ZJU-50a crystal unveil that the incorporated supramolecular binding sites can selectively take up C2 H2 molecule but not CO2 to result in both high C2 H2 storage and selectivity. Breakthrough experiments validated its separation performance for C2 H2 /CO2 mixtures, providing a high C2 H2 recovery capacity of 84.2 L kg-1 with 99.5 % purity. This study suggests a novel strategy of engineering supramolecular binding sites into MOFs to overcome the trade-off for this separation.

Immobilization of Lewis Basic Sites into a Stable Ethane-Selective MOF Enabling One-Step Separation of Ethylene from a Ternary Mixture.

Purification of C2H4 from a ternary C2H2/C2H6/C2H4 mixture by one-step adsorption separation is of prime importance but challenging in the petrochemical industry; however, effective strategies to design high-performance adsorbents are lacking. We herein report for the first time the incorporation of Lewis basic sites into a C2H6-selective MOF, enabling efficient one-step production of polymer-grade C2H4 from ternary mixtures. Introduction of amino groups into highly stable C2H6-selective UiO-67 can not only partition large pores into smaller cagelike pockets to provide suitable pore confinement but also offer additional binding sites to simultaneously enhance C2H2 and C2H6 adsorption capacities over C2H4. The amino-functionalized UiO-67-(NH2)2 thus exhibits exceptionally high C2H2 and C2H6 uptakes as well as benchmark C2H2/C2H4 and C2H6/C2H4 selectivities, surpassing all of the C2H2/C2H6-selective materials reported so far. Theoretical calculations combined with in situ infrared spectroscopy indicate that the synergetic effect of suitable pore confinement and functional surfaces decorated with amino groups provides overall stronger multipoint van der Waals interactions with C2H2 and C2H6 over C2H4. The exceptional performance of UiO-67-(NH2)2 was evidenced by breakthrough experiments for C2H2/C2H6/C2H4 mixtures under dry and wet conditions, providing a remarkable C2H4 productivity of 0.55 mmol g-1 at ambient conditions.

Immobilization of Lewis Basic Nitrogen Sites into a Chemically Stable Metal-Organic Framework for Benchmark Water-Sorption-Driven Heat Allocations.

Developing efficient and stable water adsorbents for adsorption-driven heat transfer technology still remains a challenge due to the lack of efficient strategies to enhance low-pressure water uptakes. The authors herein demonstrate that the immobilization of Lewis basic nitrogen sites into metal-organic frameworks (MOFs) can improve water uptake and target benchmark coefficient of performances (COPs) for cooling and heating. They present the water sorption properties of a chemically stable MOF (termed as Zr-adip), designed by incorporating hydrophilic nitrogen sites into the adsorbent MIP-200. Zr-adip exhibits S-shaped sorption isotherms with an extremely high water uptake of 0.43 g g-1  at 303 K and P/P0  = 0.25, higher than MIP-200 (0.39 g g-1 ), KMF-1 (0.39 g g-1 ) and MOF-303 (0.38 g g-1 ). Theoretical calculations reveal that the incorporated N sites can serve as secondary adsorption sites to moderately interact with water, providing more binding sites to strengthen the water binding affinity. Zr-adip achieves exceptionally high COPs of 0.79 (cooling) and 1.75 (heating) with a low driving temperature of 70 °C, outperforming MIP-200 (0.78 and 1.53) and KMF-1 (0.75 and 1.74). Combined with its ultrahigh stability, excellent cycling performance, and easy regeneration, Zr-adip represents one of the best water adsorbents for adsorption-driven cooling and heating.

Robust and Radiation-Resistant Hofmann-Type Metal-Organic Frameworks for Record Xenon/Krypton Separation.

The discovery of high-performance adsorbents for highly efficient separation of xenon from krypton is an important but challenging task in the chemical industry due to their similar size and inert spherical nature. Herein, we report two robust and radiation-resistant Hofmann-type MOFs, Co(pyz)[Ni(CN)4] and Co(pyz)[Pd(CN)4] (termed as ZJU-74a-Ni and ZJU-74a-Pd), featuring oppositely adjacent open metal sites and perfect pore sizes (4.1 and 3.8 Å) comparable to the kinetic diameter of xenon (4.047 Å), affording the benchmark binding affinity for polarizable Xe gas. These materials thus exhibit both record-high Xe uptake capacities (89.3 and 98.4 cm3 cm-3 at 296 K and 0.2 bar) and Xe/Kr selectivities (74.1 and 103.4) at ambient conditions, all of which are the highest among all the state-of-the-art materials reported so far. The locations of Xe molecules within ZJU-74a-Ni have been visualized by single-crystal X-ray diffraction studies, in which two oppositely adjacent metal centers combined with the right aperture size can construct a unique sandwich-like binding site to offer unprecedented and ultrastrong Ni2+-Xe-Ni2+ interactions with xenon, thus leading to the record Xe capture capacity and selectivity. The excellent separation capacity of ZJU-74a-Pd was verified by breakthrough experiments for Xe/Kr gas mixtures, providing both unprecedentedly high xenon uptake capacity (4.63 mmol cm-3) and krypton productivity (214 cm3 g-1).

Efficient CO2/CO separation in a stable microporous hydrogen-bonded organic framework.

We herein realize the first example of using a microporous HOF material (ZJU-HOF-1) with suitable pore cavities for highly efficient CO2/CO separation under dry and humid conditions.

Dense Packing of Acetylene in a Stable and Low-Cost Metal-Organic Framework for Efficient C2 H2 /CO2 Separation.

Porous materials for C2 H2 /CO2 separation mostly suffer from high regeneration energy, poor stability, or high cost that largely dampen their industrial implementation. A desired adsorbent should have an optimal balance between excellent separation performance, high stability, and low cost. We herein report a stable, low-cost, and easily scaled-up aluminum MOF (CAU-10-H) for highly efficient C2 H2 /CO2 separation. The suitable pore confinement in CAU-10-H can not only provide multipoint binding interactions with C2 H2 but also enable the dense packing of C2 H2 inside the pores. This material exhibits one of the highest C2 H2 storage densities of 392 g L-1 and highly selective adsorption of C2 H2 over CO2 at ambient conditions, achieved by a low C2 H2 adsorption enthalpy (27 kJ mol-1 ). Breakthrough experiments confirm its exceptional separation performance for C2 H2 /CO2 mixtures, affording both large C2 H2 uptake of 3.3 mmol g-1 and high separation factor of 3.4. CAU-10-H achieves the benchmark balance between separation performance, stability, and cost for C2 H2 /CO2 separation.

Chemically Stable Hafnium-Based Metal-Organic Framework for Highly Efficient C2H6/C2H4 Separation under Humid Conditions.

Realization of ethane-selective porous materials for efficient ethane/ethylene (C2H6/C2H4) separation is an important task in the petrochemical industry. Although a number of C2H6-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 C2H6 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 C2H6/C2H4 separation under humid conditions. Gas sorption results reveal that (Hf)DUT-52a exhibits both high ethane adsorption capacity (4.02 mmol g-1) and C2H6/C2H4 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.

Synergism of irbesartan and amlodipine on hemodynamic amelioration and organ protection in spontaneously hypertensive rats.

AIM: To investigate the synergism of low-doses of amlodipine and irbesartan on reduction of blood pressure variability (BPV), amelioration of baroreflex sensitivity (BRS) and organ protection in spontaneously hypertensive rats (SHR). METHODS: The rats were administered amlodipine (1 mg·kg(-1)·d(-1)) alone, irbesartan (10 mg·kg(-1)·d(-1)) alone, or the combination of the two drugs for 4 months. The drugs were mixed into the rat chow. Blood pressure (BP) was continuously monitored in conscious animals. After the determination of BRS, the rats were killed for morphological evaluation of organ damages. RESULTS: The combination of low-dose irbesartan and amlodipine had statistically significant synergism on reduction of BP and BPV, amelioration of BRS and organ protection in SHR. Multiple regression analysis showed that the decrease in left ventricular hypertrophy was associated with the decrease in systolic BPV (r=0.665, P<0.01); the decrease in aortic hypertrophy was associated with the increase in BRS (r=0.656, P<0.01); and the amelioration in renal lesion was associated with the increase in BRS (r=0.763, P<0.01) and the decrease in systolic BPV (r=0.706, P<0.01). CONCLUSION: Long-term treatment with a combination of low-doses of amlodipine and irbesartan showed significant synergism on reduction of BP and BPV, restoration of BRS and organ protection in SHR. Besides BP reduction, the enhancement of BRS and reduction of BPV might contribute to the organ protection.

Arterial baroreflex is not involved in salt preference in rats.

1. One unusual and interesting feature of spontaneously hypertensive rats (SHR) is their salt preference. This behaviour is known to be independent of blood pressure. 2. Arterial baroreflex (ABR) function is impaired in SHR. Therefore, the present study was designed to explore the relationship between ABR function and salt preference in rats. 3. Twenty-seven SHR, aged 11 months, were used. Blood pressure and baroreflex sensitivity (BRS) were determined in conscious, freely moving SHR after the measurement of salt preference. It was found that BRS did not relate to the salt preference in these rats. 4. Another group of normotensive Sprague-Dawley rats, aged 10 weeks, underwent either sinoaortic denervation (SAD) or sham operation. Salt preference was determined before and 4 weeks after SAD. Sinoaortic denervation did not alter salt preference in normotensive rats. 5. It is concluded that ABR function does not influence the salt preference in rats.