Confinement of noble nanometals in a zeolite matrix is a promising way to special types of catalysts that show significant advantages in size control, site adjustment, and nano‐architecture design. ...The beauty of zeolite‐confined noble metals lies in their unique confinement effects on a molecular scale, and thus enables spatially confined catalysis akin to enzyme catalysis. In this Minireview, the confined synthesis strategies of zeolite‐confined noble metals will be briefly discussed, showing the processes, advantages, features, and mechanisms. The confined catalysis carried on zeolite‐confined noble metals will be summarized, and great emphasis will be paid to the confinement effects involving size, encapsulation, recognition, and synergy. Great progress of atomic sites in the size effect, supercage stabilization in the encapsulation effect, site adsorption in the recognition effect, and cascade reaction in the synergy effect are highlighted. This Minireview is concluded with challenges and opportunities in terms of the synthesis of zeolite‐confined noble metals and their applications to design multifunctional catalysts with high catalytic activity, selectivity, and stability.
The beauty of zeolite‐confined noble metals lies in their unique confinement effects on a molecular scale, and thus enables spatially confined catalysis akin to enzyme catalysis. This Minireview summarizes synthesis strategies and targeted catalysis applications for multifunctional zeolite‐confined noble metal catalysts.
The evolution of cost‐effective and reserve‐rich nonprecious metals (NPMs) to replace precious metal electrocatalysts is of significant interest in modern electrocatalysis. The confinement effects in ...NPM‐based nanoparticles encapsulated in carbon nanoshells have been considered as an emerging and efficient way to special types of electrocatalysts which facilitate electrocatalytic activity and stability, even under rigorous conditions. This review focuses on the unique individual carbon encapsulation for high‐performance design of NPM‐based electrocatalysts, outlining all confinement synthesis methods, mechanistic studies on confinement effects, and the emerging practical reactions. It begins first introducing the synthetic methods for NPM‐based core@carbon shell electrocatalysts, and then follows clarification of the relationship between the fundamental confinement effects and the performance improvement of carbon shell encapsulating NPM‐based electrocatalysts. Further and detailed discussions on the alloying effect, doping effect, and heterojunction effect of the NPM‐based core to alter the electronic situation which affects the electrocatalytic performance are subsequently provided. Finally, the review provides a perspective on challenges and opportunities in future research with respect to both in‐depth theoretical research and potential design concept of such NPM‐based core@carbon shell electrocatalysts.
Individual nonprecious metal (NPM)‐based core@carbon shell electrocatalysts have attracted extensive attention as one of the promising electrocatalytic materials. Confined within the carbon shell endows the integral electrocatalysts with good physical and chemical properties. Further alloying, doping, and heterojunction design of the cores provide abundant options for diverse electrocatalytic reactions. The structure–performance relationship is comprehensively reviewed via the experimental results and theoretical calculations.
Safety issues associated with proton pump inhibitors (PPIs) have recently attracted widespread media and lay attention. Gastroenterologists are frequently asked about the appropriateness of PPI ...therapy for specific patients. Furthermore, some patients may have had PPI therapy discontinued abruptly or inappropriately due to safety concerns. Faced with such a wide variety of potentially serious adverse consequences, prescribers need to evaluate the evidence objectively to discern the likelihood that any reported association might actually be causal. Here, we review many of the proposed adverse consequences of PPI therapy and apply established criteria for the determination of causation. We also consider the potential contribution of residual confounding in many of the reported studies. Evidence is inadequate to establish causal relationships between PPI therapy and many of the proposed associations. Residual confounding related to study design and the overextrapolation of quantitatively small estimates of effect size have probably led to much of the current controversy about PPI safety. In turn, this has caused unnecessary concern among patients and prescribers. The benefits of PPI therapy for appropriate indications need to be considered, along with the likelihood of the proposed risks. Patients with a proven indication for a PPI should continue to receive it in the lowest effective dose. PPI dose escalation and continued chronic therapy in those unresponsive to initial empiric therapy is discouraged.
Background & Aims The purpose of this review is to evaluate the risks associated with long-term use of proton pump inhibitors (PPIs), focusing on long-term use of PPIs for three common indications: ...gastroesophageal reflux disease (GERD), Barrett’s esophagus (BE), and non-steroidal anti-inflammatory drug (NSAID) bleeding prophylaxis. Methods The recommendations outlined in this review are based on expert opinion and on relevant publications from PubMed, EMbase, and the Cochrane library (through July 2016). To identify relevant ongoing trials, we queried clinicaltrials.gov . To assess the quality of evidence, we used a modified approach based on the GRADE Working Group. The Clinical Practice Updates Committee of the American Gastroenterological Association has reviewed these recommendations. Best Practice Advice 1 : Patients with GERD and acid-related complications (ie, erosive esophagitis or peptic stricture) should take a PPI for short-term healing, maintenance of healing, and long-term symptom control. Best Practice Advice 2 : Patients with uncomplicated GERD who respond to short-term PPIs should subsequently attempt to stop or reduce them. Patients who cannot reduce PPIs should consider ambulatory esophageal pH/impedance monitoring before committing to lifelong PPIs to help distinguish GERD from a functional syndrome. The best candidates for this strategy may be patients with predominantly atypical symptoms or those who lack an obvious predisposition to GERD (eg, central obesity, large hiatal hernia). Best Practice Advice 3 : Patients with Barrett’s esophagus and symptomatic GERD should take a long-term PPI. Best Practice Advice 4 : Asymptomatic patients with Barrett’s esophagus should consider a long-term PPI. Best Practice Advice 5 : Patients at high risk for ulcer-related bleeding from NSAIDs should take a PPI if they continue to take NSAIDs. Best Practice Advice 6 : The dose of long-term PPIs should be periodically reevaluated so that the lowest effective PPI dose can be prescribed to manage the condition. Best Practice Advice 7 : Long-term PPI users should not routinely use probiotics to prevent infection. Best Practice Advice 8 : Long-term PPI users should not routinely raise their intake of calcium, vitamin B12, or magnesium beyond the Recommended Dietary Allowance (RDA). Best Practice Advice 9 : Long-term PPI users should not routinely screen or monitor bone mineral density, serum creatinine, magnesium, or vitamin B12. Best Practice Advice 10 : Specific PPI formulations should not be selected based on potential risks.
Owing to their immense potential in energy conversion and storage, catalysis, photocatalysis, adsorption, separation and life science applications, significant interest has been devoted to the design ...and synthesis of hierarchically porous materials. The hierarchy of materials on porosity, structural, morphological, and component levels is key for high performance in all kinds of applications. Synthesis and applications of hierarchically structured porous materials have become a rapidly evolving field of current interest. A large series of synthesis methods have been developed. This review addresses recent advances made in studies of this topic. After identifying the advantages and problems of natural hierarchically porous materials, synthetic hierarchically porous materials are presented. The synthesis strategies used to prepare hierarchically porous materials are first introduced and the features of synthesis and the resulting structures are presented using a series of examples. These involve templating methods (surfactant templating, nanocasting, macroporous polymer templating, colloidal crystal templating and bioinspired process,
i.e.
biotemplating), conventional techniques (supercritical fluids, emulsion, freeze-drying, breath figures, selective leaching, phase separation, zeolitization process, and replication) and basic methods (sol-gel controlling and post-treatment), as well as self-formation phenomenon of porous hierarchy. A series of detailed examples are given to show methods for the synthesis of hierarchically porous structures with various chemical compositions (dual porosities: micro-micropores, micro-mesopores, micro-macropores, meso-mesopores, meso-macropores, multiple porosities: micro-meso-macropores and meso-meso-macropores). We hope that this review will be helpful for those entering the field and also for those in the field who want quick access to helpful reference information about the synthesis of new hierarchically porous materials and methods to control their structure and morphology.
This review addresses recent advances in synthesis strategies of hierarchically porous materials and their structural design from micro-, meso- to macro-length scale.
Nanocell hybrids for green chemistry Geng, Wei; Wang, Li; Yang, Xiao-Yu
Trends in biotechnology (Regular ed.),
08/2022, Volume:
40, Issue:
8
Journal Article
Peer reviewed
Global concerns about reducing or minimizing the costs associated with toxic waste materials have driven the continuing development of green-cell-based biosynthesis methods. Inspired by the ...hybridization phenomenon of living organisms, recent interest has arisen in nanocell hybrids that possess multiple new functions. They have potential to propel biosynthesis into a new generation of green chemistry. This review article discusses the development of applications for nanocell hybrids in the areas of sustainable energy, clean environment, and green catalysis. Continuing advances in these hybrids will require combining knowledge from the fields of biology, physics, chemistry, material science, and engineering.
Nanocell hybrids can protect living cells by abiotic materials and possess multiple new and multiple functions such as photo, electrical, thermal, magnetic, and mechanical properties. They have helped to propel biosynthesis into a new generation of green chemistry.Cells and materials can be integrated through interface engineering and molecular recognition. These approaches have been used to tailor hybrids to desired synthetic purposes, including dynamic and reversible design, and have been applied to enhance the catalytic activity, stability, and selectivity of nanocell hybrids.A wide variety of biological and material components can be used to design nanocell hybrids for enhancing or expanding cell functions for green chemistry, such as energy production, environment remediation, and biocatalysis.
Over the last decade, significant effort has been devoted to the applications of hierarchically structured porous materials owing to their outstanding properties such as high surface area, excellent ...accessibility to active sites, and enhanced mass transport and diffusion. The hierarchy of porosity, structural, morphological and component levels in these materials is key for their high performance in all kinds of applications. The introduction of hierarchical porosity into materials has led to a significant improvement in the performance of materials. Herein, recent progress in the applications of hierarchically structured porous materials from energy conversion and storage, catalysis, photocatalysis, adsorption, separation, and sensing to biomedicine is reviewed. Their potential future applications are also highlighted. We particularly dwell on the relationship between hierarchically porous structures and properties, with examples of each type of hierarchically structured porous material according to its chemical composition and physical characteristics. The present review aims to open up a new avenue to guide the readers to quickly obtain in-depth knowledge of applications of hierarchically porous materials and to have a good idea about selecting and designing suitable hierarchically porous materials for a specific application. In addition to focusing on the applications of hierarchically porous materials, this comprehensive review could stimulate researchers to synthesize new advanced hierarchically porous solids.
A comprehensive review of the recent progress in the applications of hierarchically structured porous materials is given.
LINKED CONTENT
This article is linked to Khan et al papers. To view these articles, visit https://doi.org/10.1111/apt.16610 and https://doi.org/10.1111/apt.16707
Major advances in molecular detection are being driven by goals associated with the development of methods that are amenable to miniaturization and automation, and that have high sensitivity and low ...interference. The new detection methods are confronted by many interfacial issues, which when properly addressed can lead to improved performance. One interfacial property, special wettability, can facilitate precise delivery and local enrichment of molecules to sensing elements. This review summarizes applications of unique features of special wettability in molecular detection including (1) chemical and electrochemical reactions in anchored microdroplets on superwetting surfaces, (2) enrichment of analytes and active materials at low contact areas between droplets and superwetting surfaces, (3) complete opposite affinities of superwetting surfaces toward nonpolar/polar solutes and oil/water phases, and (4) directional droplet transportation on asymmetric superwetting surfaces. The challenges and opportunities that exist in design and applications of special wettability in interfacial delivery and enrichment for detection of a few molecules are also discussed.
This review highlights interfacial design to reach major objectives in the field of molecular detection, including high sensitivity, low interference, miniaturization and automation.
We report an alternating-reduction approach by galvanic replacement and co-reduction to enable incorporation of Pd into Pt shell, and the obtained PtPd hollow nanocubes with an enhanced alloy effect ...and highly active {100} facets show high catalytic activity and superior durability in the methanol oxidation reaction.
An alternating-reduction approach is developed to fabricate PtPd hollow nanocubes with highly catalytically-favoured {100} facets and enhanced alloy effect for efficient methanol oxidation reaction.
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