Fabrication of nickel oxide functionalized zeolite USY composite as a promising adsorbent for CO2 capture

Adsorption process is considered to be the most promising alternative for the CO₂ capture to the traditional energy-intensive amine absorption process, and the development of feasible and efficient CO₂ adsorbents is still a challenge. In this work, the NiO@USY (ultrastable Y) composites with different NiO loadings were prepared for the CO₂ adsorption using Ni(NO₃)₂ as the precursor. The composites were characterized by X-ray photoelectron spectroscopy, X-ray diffraction, nitrogen adsorption–desorption test, scanning electron microscopy analysis, and thermogravimetric analysis, and were evaluated for the CO₂ adsorption capacity, CO₂/N₂ adsorption selectivity and CO₂ cycle adsorption capacity. The characterization results show that after the activation at 423 K, the Ni(NO₃)₂ species were well dispersed into the surface of zeolite USY, and after the further activation at 823 K, Ni(NO₃)₂ could be converted into highly dispersed NiO. The adsorption results show that the presence of the active component NiO plays an important role in improving the CO₂ adsorption performance, and the NiO@USY composite with a NiO loading of 1.5 mmol·g^-1 USY support displays a high adsorption capacity and adsorption selectivity for CO₂, and shows a good cycle stability. In addition, the Clausius–Clapeyron equation was used to evaluate the isosteric heat of adsorption of CO₂ on the NiO(1.5)@USY composite, and the heat of adsorption was 17.39–38.34 kJ·mol^-1.     

Electrodeposited iodide ions imprinted polypyrrole@bismuth oxyiodide film for an electrochemically switched renewable extractor towards iodide ions

Effective extraction and regeneration of radioactive iodide is one of urgent concerns for the safe utilization of nuclear energy. As a novel environmentally benign ion separation technique, electrochemically switched ion extraction (ESIE) process can be applied for effective capture and recovery of iodide ions (I^-). Herein, a novel kelp seaweed-like core/shell I^- imprinted polypyrrole@bismuth oxyiodide (PPy/I^-@BiOI) composite film is successfully prepared for the selective I^- capture in the ESIE system. It is found that the I^- can be easily trapped in the PPy/I^-@BiOI film after I^- is in situ desorbed from the film by an electrochemical reduction process since it offers particular electroactive binding sites for I^- extraction. The I^- imprinted PPy/I^-@BiOI film displays an extraction capacity as high as 325.2 mg·g^-1 for I^- with favorable stability. In particular, the extraction and desorption of I^- is achieved by adjusting the redox potential and the pristine PPy/I^-@BiOI film can be regenerated and reused for multiple times without decrease in extraction capacity. It is expected that such a PPy/I^-@BiOI film would be useful as an electrochemically switched renewable extractor that could capture and regenerate I^- from radioactive water.     

Recent advances in nanofiltration,reverse osmosis membranes and their applications in biomedical separation field

In the face of human society's great requirements for health industry, and the much stricter safety and quality standards in the biomedical industry, the demand for advanced membrane separation technologies continues to rapidly grow in the world. Nanofiltration (NF) and reverse osmosis (RO) as the high-efficient, low energy consumption, and environmental friendly membrane separation techniques, show great promise in the application of biomedical separation field. The chemical compositions, microstructures and surface properties of NF/RO membranes determine the separation accuracy, efficiency and operation cost in their applications. Accordingly, recent studies have focused on tuning the structures and tailoring the performance of NF/RO membranes via the design and synthesis of various advanced membrane materials, and exploring universal and convenient membrane preparation strategies, with the objective of promoting the better and faster development of NF/RO membrane separation technology in the biomedical separation field. This paper reviews the recent studies on the NF/RO membranes constructed with various materials, including the polymeric materials, different dimensional inorganic/organic nanomaterials, porous polymeric materials and metal coordination polymers, etc. Moreover, the influence of membrane chemical compositions, interior microstructures, and surface characteristics on the separation performance of NF/RO membranes, are comprehensively discussed. Subsequently, the applications of NF/RO membranes in biomedical separation field are systematically reported. Finally, the perspective for future challenges of NF/RO membrane separation techniques in this field is discussed.     

Thermodynamic analysis of reaction pathways and equilibrium yields for catalytic pyrolysis of naphtha

The chain length and hydrocarbon type significantly affect the production of light olefins during the catalytic pyrolysis of naphtha. Herein, for a better catalyst design and operation parameters optimization, the reaction pathways and equilibrium yields for the catalytic pyrolysis of C_5–8 n/iso/cyclo-paraffins were analyzed thermodynamically. The results revealed that the thermodynamically favorable reaction pathways for n/iso-paraffins and cyclo-paraffins were the protolytic and hydrogen transfer cracking pathways, respectively. However, the formation of light paraffin severely limits the maximum selectivity toward light olefins. The dehydrogenation cracking pathway of n/iso-paraffins and the protolytic cracking pathway of cyclo-paraffins demonstrated significantly improved selectivity for light olefins. The results are thus useful as a direction for future catalyst improvements, facilitating superior reaction pathways to enhance light olefins. In addition, the equilibrium yield of light olefins increased with increasing the chain length, and the introduction of cyclo-paraffin inhibits the formation of light olefins. High temperatures and low pressures favor the formation of ethylene, and moderate temperatures and low pressures favor the formation of propylene. n-Hexane and cyclohexane mixtures gave maximum ethylene and propylene yield of approximately 49.90% and 55.77%, respectively. This work provides theoretical guidance for the development of superior catalysts and the selection of proper operation parameters for the catalytic pyrolysis of C_5–8 n/iso/cyclo-paraffins from a thermodynamic point of view.     

Rational design on photoelectrodes and devices to boost photoelectrochemical performance of solar-driven water splitting: a mini review

As an eco-friendly, efficient, and low-cost technique, photoelectrochemical water splitting has attracted growing interest in the production of clean and sustainable hydrogen by the conversion of abundant solar energy. In the photoelectrochemical system, the photoelectrode plays a vital role in absorbing the energy of sunlight to trigger the water splitting process and the overall efficiency depends largely on the integration and design of photoelectrochemical devices. In recent years, the optimization of photoelectrodes and photoelectrochemical devices to achieve highly efficient hydrogen production has been extensively investigated. In this paper, a concise review of recent advances in the modification of nanostructured photoelectrodes and the design of photoelectrochemical devices is presented. Meanwhile, the general principles of structural and morphological factors in altering the photoelectrochemical performance of photoelectrodes are discussed. Furthermore, the performance indicators and first principles to describe the behaviors of charge carriers are analyzed, which will be of profound guiding significance to increasing the overall efficiency of the photoelectrochemical water splitting system. Finally, current challenges and prospects for an in-depth understanding of reaction mechanisms using advanced characterization technologies and potential strategies for developing novel photoelectrodes and advanced photoelectrochemical water splitting devices are demonstrated.     

Optimising the oil phases of aluminium hydrogel-stabilised emulsions for stable,safe and efficient vaccine adjuvant

To increase antibody secretion and dose sparing, squalene-in-water aluminium hydrogel (alum)-stabilised emulsions (ASEs) have been developed, which offer increased surface areas and cellular interactions for higher antigen loading and enhanced immune responses. Nevertheless, the squalene (oil) in previous attempts suffered from limited oxidation resistance, thus, safety and stability were compromised. From a clinical translational perspective, it is imperative to screen the optimal oils for enhanced emulsion adjuvants. Here, because of the varying oleic to linoleic acid ratio, soybean oil, peanut oil, and olive oil were utilised as oil phases in the preparation of aluminium hydrogel-stabilised squalene-in-water emulsions, which were then screened for their stability and immunogenicity. Additionally, the underlying mechanisms of oil phases and emulsion stability were unravelled, which showed that a higher oleic to linoleic acid ratio increased anti-oxidative capabilities but reduced the long-term storage stability owing to the relatively low zeta potential of the prepared droplets. As a result, compared with squalene-in-water ASEs, soybean-in-water ASEs exhibited comparable immune responses and enhanced stability. By optimising the oil phase of the emulsion adjuvants, this work may offer an alternative strategy for safe, stable, and effective emulsion adjuvants.     

Intermediate space for housing design learned from tradition of Korean maru and Turkish sofa

The study examines traditional design approaches for intermediate spaces of residential buildings to support environmentally driven design strategies of current practices. For the evaluation of the potential of traditional design strategies, traditional houses of Korea and Turkey are explored by making a detailed comparison of maru and sofa according to theoretical considerations on intermediate spaces. After examining the concept of the intermediate space and the general characteristics of Korean and Turkish traditional housing, 10 cases from 17th to 19th centuries are selected and compared to clarify the features of maru and sofa as intermediate spaces. Based on the results, the arrangement of maru shows characteristics of contradiction between interior rooms and intermediate spaces in a monotonous structural repetition, while sofa presents an apparently hierarchical spatial composition. Sofa has the placeness quality, while maru has the quality of plurality, actively mixing both inside and outside environments. While maru allows various free access with clear spatial continuity, sofa produces a sequential spatial experience with the pleasure of different architectural qualities. Finally, the study suggests opened type and closed type of intermediate space as two possible strategies for modern houses based on the results of comparative analyses. Recent environmental studies in architecture should consider intermediate spaces of various traditional houses due to the insights and possibilities these spatial elements may potentially provide to both architectural practice and theory, especially in a pandemic era.     

橡胶粉和硅灰对碱硅酸反应的抑制作用

采用快速砂浆棒法,研究废旧轮胎橡胶粉（WRP）和硅灰（SF）单掺及两者复掺对碱硅酸反应（ASR）引起有害膨胀的抑制作用,并分析WRP粒径对ASR抑制作用的影响;结合扫描电镜和X射线衍射等方法,揭示了两者对活性骨料ASR的抑制机理.结果表明：WRP能够抑制ASR,但其粒径会影响抑制效果,其中0.125 mm （120 目） WRP效果最佳;SF对ASR抑制作用早期较好,而后期不够理想;复掺SF和WRP对抑制ASR膨胀协同作用优异,前期SF发生火山灰反应,水化产物具有缚碱能力,有效抑制ASR负面效应,改善了WRP周边砂浆的密实性,后期WRP利用其物理性能降低膨胀压,从而协同缓解了ASR引起的膨胀.