One-Step Butadiene Purification in a Sulfonate-Functionalized Metal-Organic Framework through Synergistic Separation Mechanism.

Porous materials that could recognize specific molecules from complex mixtures are of great potential in improving the current energy-intensive multistep separation processes. However, due to the highly similar structures and properties of the mixtures, the design of desired porous materials remains challenging. Herein, a sulfonate-functionalized metal-organic framework ZU-609 with suitable pore size and pore chemistry is designed for 1,3-butadiene (C4H6) purification from complex C4 mixtures. The sulfonate anions decorated in the channel achieve selective recognition of C4H6 from other C4 olefins with subtle polarity differences through C-H⋅⋅⋅O-S interactions, affording recorded C4H6/trans-2-C4H8 selectivity (4.4). Meanwhile, the shrunken mouth of the channel with a suitable pore size (4.6 Å) exhibits exclusion effect to the larger molecules cis-2-C4H8, iso-C4H8, n-C4H10 and iso-C4H10. Benefiting from the moderate C4 olefins binding affinity exhibited by sulfonate anions, the adsorbed C4H6 could be easily regenerated near ambient conditions. Polymer-grade 1,3-butadiene (99.5 %) is firstly obtained from 7-component C4 mixtures via one adsorption-desorption cycle. The work demonstrates the great potential of synergistic recognition of size-sieving and thermodynamically equilibrium in dealing with complex mixtures.

Sulfonate Functional Ultramicroporous Materials with Suitable Pore Size and Layer-Stacked Structure for C4 Olefins Purification.

Selective recognition of 1,3-butadiene from complex olefin isomers is vital for 1,3-butadiene purification, but the lack of porous materials with suitable pore structures results in poor selectivity and low capacity in C4 olefin separation. Herein, two sulfonate-functionalized organic frameworks, ZU-601 and ZU-602, are designed and show impressive separation performance toward C4 olefins. Benefiting from the suitable aperture size caused by the flexibility of coordinated organic ligand, ZU-601, ZU-602 that are pillared with different sulfonate anions could discriminate C4 olefin isomers with high uptake ratio: 1,3-butadiene/1-butene (207), 1,3-butadiene/trans-2-butene (10.1). Meanwhile, their layer-stacked structure enables the utilization of both intra- and interlayer space, enhancing the accommodation of guest molecules. ZU-601 exhibits record high 1,3-butadiene adsorption capacity of 2.90 mmol g-1 (0.5 bar, 298 K) among the reported flexible porous materials with high 1,3-butadiene/1-butene selectivity. The breakthrough experiments confirm their superior separation ability even for all five C4 olefin isomers, and the molecular-level structural change is well elucidated via powder, crystal analysis, and simulation studies. The work provides ideas toward advanced materials design with simultaneous high separation capacity and high separation selectivity for challenging separations.

A molecular sieve with ultrafast adsorption kinetics for propylene separation.

The design of molecular sieves is vital for gas separation, but it suffers from a long-standing issue of slow adsorption kinetics due to the intrinsic contradiction between molecular sieving and diffusion within restricted nanopores. We report a molecular sieve ZU-609 with local sieving channels that feature molecular sieving gates and rapid diffusion channels. The precise cross-sectional cutoff of molecular sieving gates enables the exclusion of propane from propylene. The coexisting large channels constituted by sulfonic anions and helically arranged metal-organic architectures allow the fast adsorption kinetics of propylene, and the measured propylene diffusion coefficient in ZU-609 is one to two orders of magnitude higher than previous molecular sieves. Propylene with 99.9% purity is obtained through breakthrough experiments with a productivity of 32.2 L kg-1.

Direct prediction of gas adsorption via spatial atom interaction learning.

Physisorption relying on crystalline porous materials offers prospective avenues for sustainable separation processes, greenhouse gas capture, and energy storage. However, the lack of end-to-end deep learning model for adsorption prediction confines the rapid and precise screen of crystalline porous materials. Here, we present DeepSorption, a spatial atom interaction learning network that realizes accurate, fast, and direct structure-adsorption prediction with only information of atomic coordinate and chemical element types. The breakthrough in prediction is attributed to the awareness of global structure and local spatial atom interactions endowed by the developed Matformer, which provides the intuitive visualization of atomic-level thinking and executing trajectory in crystalline porous materials prediction. Complete adsorption curves prediction could be performed using DeepSorption with a higher accuracy than Grand canonical Monte Carlo simulation and other machine learning models, a 20-35% decline in the mean absolute error compared to graph neural network CGCNN and machine learning models based on descriptors. Since the established direct associations between raw structure and target functions are based on the understanding of the fundamental chemistry of interatomic interactions, the deep learning network is rationally universal in predicting the different physicochemical properties of various crystalline materials.

Influence of E-consultation on the Intention of First-Visit Patients to Select Medical Services: Results of a Scenario Survey.

BACKGROUND: E-consultation is expected to improve the information level of patients, affect patients' subsequent judgments of medical services, and guide patients to make a reasonable medical selection in the future. Thus, it is important to understand the influence mechanism of e-consultation on patients' medical selection. OBJECTIVE: This study aims to explore the changes in first-visit patients' understanding of disease and medical resources after e-consultation as well as the choice of follow-up medical services. METHODS: Patients' medical selection before and after e-consultation was compared using a scenario survey. Based on the service characteristics of the e-consultation platform, representative simulation scenarios were determined, and parallel control groups were set up considering the order effect in comparison. Finally, a total of 4 scenario simulation questionnaires were designed. A total of 4164 valid questionnaires were collected through the online questionnaire collection platform. Patients' perception of disease severity, evaluation of treatment capacity of medical institutions, selection of hospitals and doctors, and other outcome indicators were tested to analyze the differences in patients' evaluation and choice of medical services before and after e-consultation. Additionally, the results' stability was tested by regression analysis. RESULTS: In scenario 1 (mild case), before e-consultation, 14.1% (104/740) of participants considered their conditions as not serious. After e-consultation, 69.5% (539/775) of them considered their diseases as not serious. Furthermore, participants' evaluation of the disease treatment capacity of medical institutions at all levels had improved after using e-consultation. In scenario 3 (severe case), before e-consultation, 54.1% (494/913) of the participants believed their diseases were very serious. After e-consultation, 16.6% (157/945) considered their diseases were very serious. The evaluation of disease treatment capacity of medical institutions in nontertiary hospitals decreased, whereas that of tertiary hospitals improved. In both mild and severe cases, before e-consultation, all of the participants were inclined to directly visit the hospital. After e-consultation, more than 71.4% (553/775) of the patients with mild diseases chose self-treatment, whereas those with severe diseases still opted for a face-to-face consultation. After e-consultation, patients who were set on being treated in a hospital, regardless of the disease severity, preferred to select the tertiary hospitals. Of the patients with mild diseases who chose to go to a hospital, 25.7% (57/222) wanted to consult online doctors face-to-face. By contrast, 56.4% (506/897) of the severe cases wanted to consult online doctors face-to-face. CONCLUSIONS: E-consultation can help patients accurately enhance their awareness of the disease and guide them to make a more reasonable medical selection. However, it is likely that e-consultation makes online medical services centralized. Additionally, the guiding effect of e-consultation is limited, and e-consultation needs to be combined with other supporting systems conducive to medical selection to play an improved role.

A Robust Metal-Organic Framework with Scalable Synthesis and Optimal Adsorption and Desorption for Energy-Efficient Ethylene Purification.

Adsorptive separation is an energy-efficient alternative, but its advancement has been hindered by the challenge of industrially potential adsorbents development. Herein, a novel ultra-microporous metal-organic framework ZU-901 is designed that satisfies the basic criteria raised by ethylene/ethane (C2 H4 /C2 H6 ) pressure swing adsorption (PSA). ZU-901 exhibits an "S" shaped C2 H4 curve with high sorbent selection parameter (65) and could be mildly regenerated. Through green aqueous-phase synthesis, ZU-901 is easily scalable with 99 % yield, and it is stable in water, acid, basic solutions and cycling breakthrough experiments. Polymer-grade C2 H4 (99.51 %) could be obtained via a simulating two-bed PSA process, and the corresponding energy consumption is only 1/10 of that of simulating cryogenic distillation. Our work has demonstrated the great potential of pore engineering in designing porous materials with desired adsorption and desorption behavior to implement an efficient PSA process.

Kinetic-Sieving of Carbon Dioxide from Acetylene through a Novel Sulfonic Ultramicroporous Material.

The engineering and tailoring of porous materials to realize the precise discrimination of CO2 and C2 H2 , with almost identical kinetic diameters, is a challenging task. We herein report the first example of the kinetic-sieving of relatively larger molecule of C2 H2 from CO2 by a novel sulfonic anion-pillared hybrid ultramicroporous materials of ZU-610a. Specifically, ZU-610 constructed from copper(II), isonicotinic acid and 1,2-ethanedisulfonic acid is synthesized and shows the preferential affinity for C2 H2 over CO2 . After the post-synthetic heat treatment of ZU-610, ZU-610a with a contracted aperture is obtained. Interestingly, the C2 H2 -selctive ZU-610 was reversed to the CO2 -selective ZU-610a. High purity C2 H2 (>99.5 %) could be directly obtained from the dynamic breakthrough experiments on an equimolar C2 H2 /CO2 mixture at 298 K. This study provides guidance for the design of adsorbents aimed at separation systems with similar kinetic diameter.

Perceived Factors Influencing the Public Intention to Use E-Consultation: Analysis of Web-Based Survey Data.

BACKGROUND: Unbalanced distribution of medical resources is becoming a major challenge, particularly in the selection of doctors. e-Consultation could provide patients with more choices of doctors and break the constraints of time and space. However, the acceptance of e-consultation is still poor and the mechanism of adoption is unclear. OBJECTIVE: The aim of this study was to identify the factors influencing the public intention to use e-consultation and explore the effect path of the factors and behavior intention. METHODS: The hypotheses of our research model were developed based on the technology acceptance model and perceived risk theory. A web-based survey was conducted by an electronic questionnaire collection platform; this survey that consisted of a 29-item questionnaire with 5-point Likert scales was completed by 934 respondents. Structural equation modeling was used to analyze the data. Item evaluation and reliability, validity, path loading, goodness of fit, and multiple group analysis were used to check the moderation effects. RESULTS: The standardized factor loadings of the items were between 0.551 and 0.873. The composite reliability of 9 constructs ranged from 0.706 to 0.840. The average variance extracted ranged from 0.387 to 0.640. The fitness indices showed that the collected data fitted well with the research model. Perceived usefulness was the strongest positive factor effecting behavior intention (ß=.399, P<.001). Perceived ease of use had a positive effect on behavior intention but it was not statistically significant (ß=.117, P=.07) and it had a positive effect on perceived usefulness (ß=.537, P<.001). Perceived risk could be well explained by financial risk (ß=.972, P<.001), privacy risk (ß=.774, P<.001), social risk (ß=.871, P<.001), time risk (ß=.894, P<0.001), and psychological risk (ß=.774, P<.001). Perceived risk had negative effects on perceived usefulness (ß=-.375, P<.001) and behavior intention (ß=-.297, P<.001). Personal innovativeness had a positive influence on perceived ease of use (ß=.241, P<.001) and a slight effect on behavior intention (ß=.124, P=.001). Age (χ258=133.5, P<.001) and usage experience (χ258=82.5, P=.02) had a slight moderation effect on the paths. CONCLUSIONS: Perceived usefulness and perceived risk have significant effects on public intention to use e-consultation. Therefore, platform and manufacturer must improve the function of e-consultation, which will promote the public intention to use e-consultation fundamentally. In order to control the perceived risk of public, government should play an important role in enforcing management of e-consultation markets and approving corresponding medical insurance policies. Besides, personal innovativeness had an effect on behavior intention. Moreover, the paths of factors had some heterogeneity among people with different characteristics. Therefore, it is necessary to adjust the strategies to fit more groups better.

Fine-Tuning Pore Dimension in Hybrid Ultramicroporous Materials Boosting Simultaneous Trapping of Trace Alkynes from Alkenes.

Removing trace amounts of alkynes from alkenes is one of the most critical and challenging steps to produce high-purity alkenes, the fundamental raw materials in petrochemical industry. Selective hydrogenation using noble metal catalysts under harsh conditions can convert trace alkynes to alkenes, but suffers from limited selectivity, over-hydrogenation, and energy-intensive consumption. Herein, the simultaneously adsorptive removal of trace propyne (C3 H4 ) and acetylene (C2 H2 ) from quaternary C2 H2 /C2 H4 /C3 H4 /C3 H6 mixture is reported for the first time using an anion-pillared hybrid ultramicroporous material ZU-16-Co (or TIFSIX-3-Co) by finely tuning the pore dimensions and introducing different binding sites to match the shape of alkynes. ZU-16-Co with contracted aperture size and judiciously extended cell dimension simultaneously exhibits superior trapping capacity for propyne under low concentration (2.45 mmol g-1 at 5000 ppm) and surprisingly high C2 H2 uptake (4.18 and 1.4 mmol g-1 at 1.0 and 0.01 bar, respectively) through synergistic host-guest and guest-guest interactions. Importantly, the ability of ZU-16-Co to capture trace alkynes (C2 H2 and C3 H4 ) in one step is confirmed by breakthrough experiments for quaternary C3 H4 /C2 H2 /C3 H6 /C2 H4 mixtures, presenting ZU-16-Co as a promising material for alkyne trapping.

Profit distribution and managers' behaviour in vertical integrated medical delivery systems - an experimental economics study.

BACKGROUND: The vertical integration of medical delivery systems (VIMDSs) is a reform direction both in China and worldwide. We conducted a controlled economic experiment to explore decision-making by managers of medical institutions with respect to profits and what influences the distribution mechanism in VIMDSs. METHODS: Students and hospital staff were recruited to make choices regarding the role of directors of institutions. z-Tree software was used to design the experimental program. Ninety-six subjects participated in the experiment. We gathered 479 valid contracts. RESULTS: Of the subjects, 66.39% chose flexible contracts. The median of the bidding distribution rate to community health service centres of all auctions was 18.50%. The final distribution rate was approximately 3 percentage points higher than the bidding distribution rate. The median effort level was 9.00. There was a significant correlation between the improvement rate and the choice of effort level (P<0.05) in flexible contracts. CONCLUSIONS: Hospital managers have a preference for flexible contracts because of uncertainty in the medical system. A community health service centre director may behave perfunctorily by engaging in shading in the integration. Flexible contracts and sharing rates beyond the participants' expectations motivate managers to engage in more cooperative behaviours.

Mechano-assisted synthesis of an ultramicroporous metal-organic framework for trace CO2 capture.

An ultramicroporous MOF, ZU-36-Ni (GeFSIX-3-Ni) is obtained for the first time via a mechanochemical-assisted approach. The material exhibits excellent performance for trace CO2 capture (1.07 mmol g-1 at 400 ppm) and benchmark 50/50 CO2/CH4 selectivity of 930, which is proven by dynamic breakthrough tests.

Efficient Separation of n-Butene and iso-Butene by Flexible Ultramicroporous Metal-Organic Frameworks with Pocket-like Cavities.

Efficient separation of n-butene (n-C4 H8 ) and iso-butene (iso-C4 H8 ) is of significance for the upgrading of C4 olefins to high-value end products but remains one of the major challenges in hydrocarbon purifications owing to their similar structures. Herein, we report a flexible metal-organic framework, MnINA (INA=isonicotinate), featuring one-dimensional pore channels with periodically large pocket-like cavities connected by narrow bottlenecks, for the first time for efficient n-/iso-C4 H8 separation. MnINA with smaller pore size (4.62 Å) compared with CuINA (4.84 Å), exhibits steep adsorption isotherms and high capacity of 1.79 mmol g-1 for n-C4 H8 (4.46 Å) through strong host-guest interactions via C-H⋅⋅⋅π bonding. The narrow bottlenecks exert barriers for the large molecules of iso-C4 H8 (4.84 Å) within the gate-opening pressure range of 0-0.1 bar. This gives rise to MnINA with excellent separation selectivity of 327.7 for n-/iso-C4 H8 mixture. The adsorption mechanism for n-C4 H8 and the gate-opening effect were investigated by dispersion-corrected density functional (DFT-D) theory, verifying the strong interactions between n-C4 H8 and the frameworks as well as the gate-opening effect derived from the rotation of organic linkers. The breakthrough tests confirmed MnINA and CuINA can be promising candidates for n-/iso-C4 H8 separation.