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1.
J Am Chem Soc ; 146(6): 4153-4161, 2024 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-38300827

RESUMEN

Separating ethane (C2H6) from ethylene (C2H4) is an essential and energy-intensive process in the chemical industry. Here, we report two flexible diamondoid coordination networks, X-dia-1-Ni and X-dia-1-Ni0.89Co0.11, that exhibit gate-opening between narrow-pore (NP) and large-pore (LP) phases for C2H6, but not for C2H4. X-dia-1-Ni0.89Co0.11 thereby exhibited a type F-IV isotherm at 273 K with no C2H6 uptake and a high uptake (111 cm3 g-1, 1 atm) for the NP and LP phases, respectively. Conversely, the LP phase exhibited a low uptake of C2H4 (12.2 cm3 g-1). This C2H6/C2H4 uptake ratio of 9.1 for X-dia-1-Ni0.89Co0.11 far surpassed those of previously reported physisorbents, many of which are C2H4-selective. In situ variable-pressure X-ray diffraction and modeling studies provided insight into the abrupt C2H6-induced structural NP to LP transformation. The promise of pure gas isotherms and, more generally, flexible coordination networks for gas separations was validated by dynamic breakthrough studies, which afforded high-purity (99.9%) C2H4 in one step.

2.
Intern Med J ; 53(11): 2042-2049, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-36710434

RESUMEN

BACKGROUND: Studies evaluating the economic burden of dermatological care in the transplant setting are currently not available in Australia. AIMS: To evaluate the clinical and economic burden of benign and malignant skin lesions in renal transplant recipients in Central Queensland. METHODS: A bottom-up approach was used to determine the clinical burden and direct costs from patient-level Medicare data obtained from Service Australia for skin lesions. RESULTS: Seventy-six percent of the renal transplant population in Central Queensland participated in this study. The median age was 57.0 years (standard deviation ± 13.6) and the majority (61.8%) of participants were men. The mean duration after transplant surgery was 99.9 months (interquartile range, 73.2-126.6 months). During a 2-year follow-up, 22 (40%) patients were diagnosed with benign skin lesions, 21 (38%) with nonmelanoma skin carcinoma (NMSC) and one (2%) with melanoma. There was a total of 231 visits to clinicians for diagnostic and therapeutic skin procedures and the direct costs to Medicare was $48 806 Australian Dollars (AUD) or $30 427 US Dollars (USD). Approximately 86% of the total direct costs was spent for nonNMSC and mean direct costs for NMSC was $763 AUD (or $476 USD). CONCLUSION: This Medicare data-based study provides further insight into the burgeoning clinical and economic burden of the care for benign and malignant skin lesions in the renal transplantation setting in Australia.


Asunto(s)
Carcinoma Basocelular , Carcinoma de Células Escamosas , Trasplante de Riñón , Neoplasias Cutáneas , Masculino , Humanos , Anciano , Femenino , Persona de Mediana Edad , Carcinoma Basocelular/epidemiología , Carcinoma de Células Escamosas/epidemiología , Carcinoma de Células Escamosas/patología , Estrés Financiero , Australia/epidemiología , Factores de Riesgo , Programas Nacionales de Salud , Neoplasias Cutáneas/epidemiología , Receptores de Trasplantes
3.
J Couns Psychol ; 70(5): 451-463, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37199952

RESUMEN

Indigenous Canadians suffer disproportionately from mental health concerns tied to histories of colonization, including exposure to Indian Residential Schools. Previous research has indicated that preferred therapies for Indigenous populations fuse traditional cultural practices with mainstream treatment. The present study comprised 32 interviews conducted with Indigenous administrators, staff, and clients at a reserve-based addiction treatment center to identify community-driven and practical therapeutic solutions for remedying histories of coercive colonial assimilation. Thematic analysis of semi-structured interviews revealed that counselors tailored therapy through cultural preferences, including the use of nonverbal expression, culturally appropriate guidance, and alternative delivery formats. Additionally, they augmented mainstream therapeutic activities with Indigenous practices, including the integration of Indigenous concepts, traditional practices, and ceremonial activities. Collectively, this integration of familiar counseling approaches and Indigenous cultural practices in response to community priorities resulted in an innovative instance of therapeutic fusion that may be instructive for cultural adaptation efforts in mental health treatment for Indigenous populations and beyond. (PsycInfo Database Record (c) 2023 APA, all rights reserved).


Asunto(s)
Consejo , Asistencia Sanitaria Culturalmente Competente , Servicios de Salud del Indígena , Indígena Canadiense , Salud Mental , Humanos , Canadá , Salud Mental/etnología , Instituciones Académicas , Asistencia Sanitaria Culturalmente Competente/etnología , Asistencia Sanitaria Culturalmente Competente/métodos
4.
Adv Mind Body Med ; 37(4): 12-19, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38466049

RESUMEN

Compared to non-Hispanic White individuals, non-Hispanic Black Individuals report worse chronic pain from a variety of medical issues. Among the options for non-pharmacological pain treatment, mind-body interventions (MBI) are a promising modality to help Black individuals manage their chronic pain effectively. MBIs such as mindfulness meditation improve chronic pain and chronic pain-related outcomes by shifting the individual's perception of pain away from stress-related cognitive appraisals, emotional reactions, and behaviors. MBIs may also address disparities in chronic pain outcomes between Black and White individuals because of their contextual overlap with (1) centering and contemplative prayer, (2) racial empowerment, and (3) social support. Despite this overlap, the demand for MBIs among Black individuals has generally been low due to lingering access and acceptability barriers. To reduce these barriers for Black individuals with chronic pain, we must adopt a community-engaged approach and culturally adapt MBIs for the specific historic, environmental, financial, and psychosocial needs of Black individuals. Example adaptations include increasing Black representation among MBI instructors, reducing geographical access barriers, accommodating the financial and personal realities of Black adults, and explicitly allowing relevant attitudes, practices, and terms.


Asunto(s)
Dolor Crónico , Adulto , Humanos , Población Negra , Dolor Crónico/terapia , Participación de la Comunidad , Disentimientos y Disputas , Participación de los Interesados , Blanco
5.
J Community Psychol ; 51(7): 2618-2634, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-36976752

RESUMEN

This study explores behavioral health services for American Indians and Alaska Natives (AIANs) at six Urban Indian Health Programs (UIHPs). Interviews and focus groups with clinicians and staff inquired about behavioral health treatment available, service needs, client population, and financial and staffing challenges. Resulting site profiles were created based on focused coding and integrative memoing of site visit field notes and respondent transcripts. These six UIHPs evidenced diversity across multiple facets of service delivery even as they were united in their missions to provide accessible and effective behavioral health treatment to urban AIAN clients. Primary challenges to service provision included heterogenous client populations, low insurance coverage, limited provider knowledge, lack of resources, and incorporation of traditional healing. Collaborative research with UIHPs harbors the potential to recognize challenges, identify solutions, and share best practices across this crucial network of health care sites for improving urban AIAN well-being.


Asunto(s)
Indio Americano o Nativo de Alaska , Servicios de Salud del Indígena , Servicios de Salud Mental , Humanos , Accesibilidad a los Servicios de Salud
6.
Angew Chem Int Ed Engl ; 62(32): e202305390, 2023 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-37261869

RESUMEN

Adsorption-based removal of carbon dioxide (CO2 ) from gas mixtures has demonstrated great potential for solving energy security and environmental sustainability challenges. However, due to similar physicochemical properties between CO2 and other gases as well as the co-adsorption behavior, the selectivity of CO2 is severely limited in currently reported CO2 -selective sorbents. To address the challenge, we create a bioinspired design strategy and report a robust, microporous metal-organic framework (MOF) with unprecedented [Mn86 ] nanocages. Attributed to the existence of unique enzyme-like confined pockets, strong coordination interactions and dipole-dipole interactions are generated for CO2 molecules, resulting in only CO2 molecules fitting in the pocket while other gas molecules are prohibited. Thus, this MOF can selectively remove CO2 from various gas mixtures and show record-high selectivities of CO2 /CH4 and CO2 /N2 mixtures. Highly efficient CO2 /C2 H2 , CO2 /CH4 , and CO2 /N2 separations are achieved, as verified by experimental breakthrough tests. This work paves a new avenue for the fabrication of adsorbents with high CO2 selectivity and provides important guidance for designing highly effective adsorbents for gas separation.

7.
Angew Chem Int Ed Engl ; 62(8): e202217662, 2023 Feb 13.
Artículo en Inglés | MEDLINE | ID: mdl-36585907

RESUMEN

Two C2 H6 -selective metal-organic framework (MOF) adsorbents with ultrahigh stability, high surface areas, and suitable pore size have been designed and synthesized for one-step separation of ethane/ethylene (C2 H6 /C2 H4 ) under humid conditions to produce polymer-grade pure C2 H4 . Experimental results reveal that these two MOFs not only adsorb a high amount of C2 H6 but also display good C2 H6 /C2 H4 selectivity verified by fixed bed column breakthrough experiments. Most importantly, the good water stability and hydrophobic pore environments make these two MOFs capable of efficiently separating C2 H6 /C2 H4 under humid conditions, exhibiting the benchmark performance among all reported adsorbents for separation of C2 H6 /C2 H4 under humid conditions. Moreover, the affinity sites and their static adsorption energies were successfully revealed by single crystal data and computation studies. Adsorbents described in this work can be used to address major chemical industrial challenges.

8.
J Am Chem Soc ; 144(4): 1681-1689, 2022 Feb 02.
Artículo en Inglés | MEDLINE | ID: mdl-34965123

RESUMEN

The removal of carbon dioxide (CO2) from acetylene (C2H2) is a critical industrial process for manufacturing high-purity C2H2. However, it remains challenging to address the tradeoff between adsorption capacity and selectivity, on account of their similar physical properties and molecular sizes. To overcome this difficulty, here we report a novel strategy involving the regulation of a hydrogen-bonding nanotrap on the pore surface to promote the separation of C2H2/CO2 mixtures in three isostructural metal-organic frameworks (MOFs, named MIL-160, CAU-10H, and CAU-23, respectively). Among them, MIL-160, which has abundant hydrogen-bonding acceptors as nanotraps, can selectively capture acetylene molecules and demonstrates an ultrahigh C2H2 storage capacity (191 cm3 g-1, or 213 cm3 cm-3) but much less CO2 uptake (90 cm3 g-1) under ambient conditions. The C2H2 adsorption amount of MIL-160 is remarkably higher than those for the other two isostructural MOFs (86 and 119 cm3 g-1 for CAU-10H and CAU-23, respectively) under the same conditions. More importantly, both simulation and experimental breakthrough results show that MIL-160 sets a new benchmark for equimolar C2H2/CO2 separation in terms of the separation potential (Δqbreak = 5.02 mol/kg) and C2H2 productivity (6.8 mol/kg). In addition, in situ FT-IR experiments and computational modeling further reveal that the unique host-guest multiple hydrogen-bonding interaction between the nanotrap and C2H2 is the key factor for achieving the extraordinary acetylene storage capacity and superior C2H2/CO2 selectivity. This work provides a novel and powerful approach to address the tradeoff of this extremely challenging gas separation.

9.
Inorg Chem ; 61(49): 19944-19950, 2022 Dec 12.
Artículo en Inglés | MEDLINE | ID: mdl-36455135

RESUMEN

A gradual amide truncation strategy was presented to tune the pore chemistry and CO2 capture performance of a series of tetracarboxylate-based Cu-MOFs. These MOFs exhibited a high density of Lewis basic sites (LBSs) and open metal sites and were prepared with the goal to enhance CO2 selective adsorption capacity. [Cu2(L1)(H2O)2]n (NJU-Bai42: NJU-Bai for Nanjing University Bai's group), [Cu2(L2) (H2O)2]n (NJU-Bai17), and [Cu2(L3)(H2O)2]n (NTUniv-60: NTUniv for Nantong University) were synthesized, and we observed that the CO2 adsorption capacities and MOF structures were impacted by subtle changes in ligands. Interestingly, although the NTUniv-60 was decorated with the least LBSs in these three MOFs, its CO2 adsorption capacity reached 270 (53.0 wt %) and 164 (32.2 wt %) cm3 g-1 at 273 and 296 K under 1 bar, respectively, which is the highest data reported for MOFs under similar conditions. From the grand canonical Monte Carlo (GCMC) simulation, the cooperative interactions between the CO2 molecules within the shuttle-shaped cages of NTUniv-60 could potentially explain why the CO2 uptake is high in this material.


Asunto(s)
Dióxido de Carbono , Bases de Lewis , Humanos , Adsorción , Amidas , Transporte Biológico
10.
Angew Chem Int Ed Engl ; 61(11): e202117807, 2022 Mar 07.
Artículo en Inglés | MEDLINE | ID: mdl-35020976

RESUMEN

The capture of the xenon and krypton from nuclear reprocessing off-gas is essential to the treatment of radioactive waste. Although various porous materials have been employed to capture Xe and Kr, the development of high-performance adsorbents capable of trapping Xe/Kr at very low partial pressure as in the nuclear reprocessing off-gas conditions remains challenging. Herein, we report a self-adjusting metal-organic framework based on multiple weak binding interactions to capture trace Xe and Kr from the nuclear reprocessing off-gas. The self-adjusting behavior of ATC-Cu and its mechanism have been visualized by the in-situ single-crystal X-ray diffraction studies and theoretical calculations. The self-adjusting behavior endows ATC-Cu unprecedented uptake capacities of 2.65 and 0.52 mmol g-1 for Xe and Kr respectively at 0.1 bar and 298 K, as well as the record Xe capture capability from the nuclear reprocessing off-gas. Our work not only provides a benchmark Xe adsorbent but proposes a new route to construct smart materials for efficient separations.

11.
J Am Chem Soc ; 143(3): 1485-1492, 2021 Jan 27.
Artículo en Inglés | MEDLINE | ID: mdl-33439004

RESUMEN

Ethylene production from C2 hydrocarbon mixtures through one separation step is desirable but challenging because of the similar size and physical properties of acetylene, ethylene, and ethane. Herein, we report three new isostructural porous coordination networks (NPU-1, NPU-2, NPU-3; NPU represents Northwestern Polytechnical University) that are sustained by 9-connected nodes based upon a hexanuclear metal cluster of composition [Mn6(µ3-O)2(CH3COO)3]6+. NPU-1/2/3 exhibit a dual cage structure that was systematically fine-tuned in terms of cage size to realize selective adsorption of C2H2 and C2H6 over C2H4. Dynamic breakthrough experiments demonstrated that NPU-1 produces ethylene in >99.9% purity from a three-component gas mixture (1:1:1 C2H2/C2H4/C2H6). Molecular modeling studies revealed that the dual adsorption preference for C2H2 and C2H6 over C2H4 originates from (a) strong hydrogen-bonding interactions between electronegative carboxylate O atoms and C2H2 molecules in one cage and (b) multiple non-covalent interactions between the organic linkers of the host network and C2H6 molecules in the second cage.

12.
J Am Chem Soc ; 143(23): 8654-8660, 2021 06 16.
Artículo en Inglés | MEDLINE | ID: mdl-34077659

RESUMEN

The development of new techniques and materials that can separate ethylene from ethane is highly relevant in modern applications. Although adsorption-based separation techniques using metal-organic frameworks (MOFs) have gained increasing attention, the relatively low stability (especially water resistance) and unscalable synthesis of MOFs severely limit their application in real industrial scenarios. Addressing these challenges, we rationally designed and synthesized two new C2H6-selective MOF adsorbents (NKMOF-8-Br and -Me) with ultrahigh chemical and thermal stability, including water resistance. Attributed to the nonpolar/hydrophobic pore environments and appropriate pore apertures, the MOFs can capture C2 hydrocarbon gases at ambient conditions even in high humidity. The single-crystal structures of gas@NKMOF-8 realized the direct visualization of adsorption sites of the gases. Both the single-crystal data and simulated data elucidate the mechanism of selective adsorption. Moreover, the NKMOF-8 possesses high C2H6 adsorption capacity and high selectivity, allowing for efficient C2H6/C2H4 separation, as verified by experimental breakthrough tests. Most importantly, NKMOF-8-Br and -Me can be scalably synthesized through stirring at room temperature in minutes, which confers them with great potential for industrial application. This work offers new adsorbents that can address major chemical industrial challenges and provides an in-depth understanding of the gas binding sites in a visual manner.

13.
Chemistry ; 27(36): 9446-9453, 2021 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-33837618

RESUMEN

Rigid molecular sieving materials are the ideal candidates for gas separation (e. g., C2 H2 /C2 H4 ) due to their ultrahigh adsorption selectivity and the absence of gas co-adsorption. However, the absolute molecular sieving effect for C2 H2 /C2 H4 separation has rarely been realized because of their similar physicochemical properties. Herein, we demonstrate the absolute molecular sieving of C2 H2 from C2 H4 by a rigid ultra-microporous metal-organic framework (F-PYMO-Cu) with 1D regular channels (pore size of ca. 3.4 Å). F-PYMO-Cu exhibited moderate acetylene uptake (35.5 cm3 /cm3 ), but very low ethylene uptake (0.55 cm3 /cm3 ) at 298 K and 1 bar, yielding the second highest C2 H2 /C2 H4 uptake ratio of 63.6 up to now. One-step C2 H4 production from a binary mixture of C2 H2 /C2 H4 and a ternary mixture of C2 H2 /CO2 /C2 H4 at 298 K was achieved and verified by dynamic breakthrough experiments. Coupled with excellent thermal and water stability, F-PYMO-Cu could be a promising candidate for industrial C2 separation tasks.

14.
Langmuir ; 37(47): 13838-13845, 2021 Nov 30.
Artículo en Inglés | MEDLINE | ID: mdl-34788027

RESUMEN

A combined experimental and theoretical study of C2H2 and CO2 adsorption and separation was performed in two isostructural molecular porous materials (MPMs): MPM-1-Cl ([Cu2(adenine)4Cl2]Cl2) and MPM-1-TIFSIX ([Cu2(adenine)4(TiF6)2]). It was revealed that MPM-1-Cl displayed higher low-pressure uptake, isosteric heat of adsorption (Qst), and selectivity for C2H2 than CO2, whereas the opposite was observed for MPM-1-TIFSIX. While MPM-1-Cl contains only one type of accessible channel, which has a greater preference toward C2H2, MPM-1-TIFSIX contains three distinct accessible channels, one of which is a confined region between two large channels that represents the primary binding site for both adsorbates. According to molecular simulations, the initial adsorption site in MPM-1-TIFSIX interacts more strongly with CO2 than C2H2, thus explaining the inversion of adsorbate selectivity relative to MPM-1-Cl.

15.
Cult Med Psychiatry ; 45(1): 97-140, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-32444961

RESUMEN

Despite extensive ethnographic and qualitative research on traditional healers in Nepal, the role of traditional healers in relation to mental health has not been synthesized. We focused on the following clinically based research question, "What are the processes by which Nepali traditional healers address mental well-being?" We adopted a scoping review methodology to maximize the available literature base and conducted a modified thematic analysis rooted in grounded theory, ethnography, and phenomenology. We searched five databases using terms related to traditional healers and mental health. We contacted key authors and reviewed references for additional literature. Our scoping review yielded 86 eligible studies, 65 of which relied solely on classical qualitative study designs. The reviewed literature suggests that traditional healers use a wide range of interventions that utilize magico-religious explanatory models to invoke symbolic transference, manipulation of local illness narratives, roles, and relationships, cognitive restructuring, meaning-making, and catharsis. Traditional healers' perceived impact appears greatest for mild to moderate forms of psychological distress. However, the methodological and sample heterogeneity preclude uniform conclusions about traditional healing. Further research should employ methods which are both empirically sound and culturally adapted to explore the role of traditional healers in mental health.


Asunto(s)
Curación por la Fe , Trastornos Mentales/terapia , Salud Mental , Personal de Salud , Humanos , Nepal , Psicoterapia
16.
Community Ment Health J ; 57(4): 777-791, 2021 05.
Artículo en Inglés | MEDLINE | ID: mdl-32894398

RESUMEN

In this Fresh Focus, we reassess what the mental health treatment gap may mean if we consider the role of traditional healing. Based on systematic reviews, patients can use traditional healers and qualitatively report improvement from general psychological distress and symptom reduction for common mental disorders. Given these clinical implications, some high-income countries have scaled up research into traditional healing practices, while at the same time in low-and middle-income countries, where the use of traditional healers is nearly ubiquitous, considerably less research funding has studied or capitalized on this phenomena. The World Health Organization 2003-2020 Mental Health Action Plan called for government health programs to include traditional and faith healers as treatment resources to combat the low- and middle-income country treatment gap. Reflection on the work which emerged during the course of this Mental Health Action Plan revealed areas for improvement. As we embark on the next Mental Health Action Plan, we offer lessons-learned for exploring potential relationships and collaborations between traditional healing and biomedicine.


Asunto(s)
Trastornos Mentales , Salud Mental , Curación por la Fe , Personal de Salud , Humanos , Trastornos Mentales/terapia , Psicoterapia
17.
Angew Chem Int Ed Engl ; 60(10): 5283-5288, 2021 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-33403811

RESUMEN

Porous materials with open metal sites have been investigated to separate various gas mixtures. However, open metal sites show the limitation in the separation of some challenging gas mixtures, such as C2 H2 /CO2 . Herein, we propose a new type of ultra-strong C2 H2 nano-trap based on multiple binding interactions to efficiently capture C2 H2 molecules and separate C2 H2 /CO2 mixture. The ultra-strong acetylene nano-trap shows a benchmark Qst of 79.1 kJ mol-1 for C2 H2 , a record high pure C2 H2 uptake of 2.54 mmol g-1 at 1×10-2  bar, and the highest C2 H2 /CO2 selectivity (53.6), making it as a new benchmark material for the capture of C2 H2 and the separation of C2 H2 /CO2 . The locations of C2 H2 molecules within the MOF-based nanotrap have been visualized by the in situ single-crystal X-ray diffraction studies, which also identify the multiple binding sites accountable for the strong interactions with C2 H2 .

18.
Angew Chem Int Ed Engl ; 60(17): 9680-9685, 2021 Apr 19.
Artículo en Inglés | MEDLINE | ID: mdl-33529471

RESUMEN

Herein, a dynamic spacer installation (DSI) strategy has been implemented to construct a series of multifunctional metal-organic frameworks (MOFs), LIFM-61/31/62/63, with optimized pore space and pore environment for ethane/ethylene separation. In this respect, a series of linear dicarboxylic acids were deliberately installed in the prototype MOF, LIFM-28, leading to a dramatically increased pore volume (from 0.41 to 0.82 cm3 g-1 ) and reduced pore size (from 11.1×11.1 Å2 to 5.6×5.6 Å2 ). The increased pore volume endows the multifunctional MOFs with much higher ethane adsorption capacity, especially for LIFM-63 (4.8 mmol g-1 ), representing nearly three times as much ethane as the prototypical counterpart (1.7 mmol g-1 ) at 273 K and 1 bar. Meanwhile, the reduced pore size imparts enhanced ethane/ethylene selectivity of the multifunctional MOFs. Theoretical calculations and dynamic breakthrough experiments confirm that the DSI is a promising approach for the rational design of multifunctional MOFs for this challenging task.

19.
Angew Chem Int Ed Engl ; 60(19): 10902-10909, 2021 May 03.
Artículo en Inglés | MEDLINE | ID: mdl-33491848

RESUMEN

Pyrazine-linked hybrid ultramicroporous (pore size <7 Å) materials (HUMs) offer benchmark performance for trace carbon capture thanks to strong selectivity for CO2 over small gas molecules, including light hydrocarbons. That the prototypal pyrazine-linked HUMs are amenable to crystal engineering has enabled second generation HUMs to supersede the performance of the parent HUM, SIFSIX-3-Zn, mainly through substitution of the metal and/or the inorganic pillar. Herein, we report that two isostructural aminopyrazine-linked HUMs, MFSIX-17-Ni (17=aminopyrazine; M=Si, Ti), which we had anticipated would offer even stronger affinity for CO2 than their pyrazine analogs, unexpectedly exhibit reduced CO2 affinity but enhanced C2 H2 affinity. MFSIX-17-Ni are consequently the first physisorbents that enable single-step production of polymer-grade ethylene (>99.95 % for SIFSIX-17-Ni) from a ternary equimolar mixture of ethylene, acetylene and CO2 thanks to coadsorption of the latter two gases. We attribute this performance to the very different binding sites in MFSIX-17-Ni versus SIFSIX-3-Zn.

20.
Angew Chem Int Ed Engl ; 60(37): 20383-20390, 2021 09 06.
Artículo en Inglés | MEDLINE | ID: mdl-34250717

RESUMEN

Structural changes at the active site of an enzyme induced by binding to a substrate molecule can result in enhanced activity in biological systems. Herein, we report that the new hybrid ultramicroporous material sql-SIFSIX-bpe-Zn exhibits an induced fit binding mechanism when exposed to acetylene, C2 H2 . The resulting phase change affords exceptionally strong C2 H2 binding that in turn enables highly selective C2 H2 /C2 H4 and C2 H2 /CO2 separation demonstrated by dynamic breakthrough experiments. sql-SIFSIX-bpe-Zn was observed to exhibit at least four phases: as-synthesised (α); activated (ß); and C2 H2 induced phases (ß' and γ). sql-SIFSIX-bpe-Zn-ß exhibited strong affinity for C2 H2 at ambient conditions as demonstrated by benchmark isosteric heat of adsorption (Qst ) of 67.5 kJ mol-1 validated through in situ pressure gradient differential scanning calorimetry (PG-DSC). Further, in situ characterisation and DFT calculations provide insight into the mechanism of the C2 H2 induced fit transformation, binding positions and the nature of host-guest and guest-guest interactions.

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