Janus membranes show great promise toward various applications and are undergoing a fast‐paced development in materials science. The asymmetric surface engineering on surface wettability, layer ...thickness, and pore structure enables Janus membranes with superiority in mass transport over conventional membranes. This review aims to provide an overview on the role of asymmetric surface engineering in membrane fabrication, structure control, and property tuning. The relationship between asymmetric surface engineering and performance optimization of Janus membranes is then elucidated based on an understanding of the underlying mass transport mechanism for target applications. Finally, current challenges in this field are highlighted, hopefully inspiring more researches to address the controllability and tunability of surface engineering for Janus membranes in future.
Janus membranes show great promise toward various applications in materials science via surface engineering. A review of the influcence of asymmetric surface engineering on the membrane fabrication, structure tuning, and performane regulation is provided based on an understanding of the underlying mass transport principle. Finally, current challenges regarding the performance optimization of Janus membranes through controllable surface engineering are highlighted.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Janus membranes (JMs) with opposite wettability have brought about new opportunities to tackle the challenging issues encountered in oil/water separation. However, these achievements suffer from ...empirical availability for the separation of oil-in-water emulsions, lacking a controllable way to tune the synergistic effect of asymmetric configurations, which is the “inner” driving force for practical performance. Herein, the role of the asymmetric configuration is theoretically and experimentally demonstrated in the Janus structural design, membrane fabrication, and separation performance for oil-in-water emulsions. These significant insights are particularly gained by analyzing Young–Laplace capillary pressures, measuring the adhesive forces between the oil and membrane surface, and monitoring the demulsification and oil transportation processes. Fluorescence imaging has been used to
in situ
visualize the separation process and then a mechanism is firstly proposed as demulsification followed by rapid unidirectional oil transportation for surfactant-stabilized oil-in-water emulsions. The two successive processes are strongly governed by the controllable asymmetric configuration of the JMs. An efficient oil separation can, therefore, be achieved from surfactant-stabilized oil-in-water emulsions with a wide size distribution (from nanometers to microns) by optimizing these two stages
via
tuning the hydrophilic/hydrophobic configuration and surface charge property of the JMs. Therefore, this work is expected to yield a design principle and guideline for developing JMs with applicability in the practical separation of oil-in-water emulsions.
Abstract
Solar‐driven evaporation process brings exciting opportunities to recover clean water and resources in a sustainable way from diverse sources like seawater and wastewater. Separation ...membranes, as a vital material in many environmental and energy applications, can contribute significantly to this process owing to their structural features. However, the unique roles of membranes in solar evaporator construction and process design are seldom recognized and not summarized yet from scientific principles and application demands, which forms the motivation of this review. Herein, the roles of membranes in different processes based on solar‐driven evaporation are focused and the design principles of membrane materials and devices to meet the requirements of these applications are discussed. Fabrication strategies for photothermal membranes are introduced primarily, followed by a discussion on how to design membrane materials, devices, and processes to pursue optimal performance and realize advanced functions accompanied by evaporation. Furthermore, the future of this field is forecast with both challenges and opportunities.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Salt scaling poses a significant obstacle to the practical implementation of solar‐driven evaporation for desalination. Attempts to mitigate scaling by enhancing mass transfer often lead to a ...compromise in evaporation efficiency due to associated heat loss. In the present work, a novel seesaw evaporator with a Janus structure to harness scaling for periodic self‐descaling is reported. The seesaw evaporators are facilely fabricated by delignifying balsa wood and subsequently single‐sided spray‐coating it with soot and polydimethylsiloxane (PDMS). This unique Janus structure enables the evaporator to float on the brine while ensuring an ample supply of solution for evaporation. During evaporation, salt ions are transported directionally toward the cocked end of the evaporator to form scaling, triggering the seesaw evaporator to flip once a threshold is reached. The accumulated salts re‐dissolve back into the solution. By adjusting the tilt angle, the evaporator can achieve an impressive evaporation rate of up to 2.65 kg m−2 h−1 when evaporating an 8 wt.% NaCl solution. Remarkably, these evaporators maintain a stable evaporation rate during prolonged 120 h operation and produce ≈3.93–6.35 L m⁻2·day⁻¹ of freshwater from simulated brines when assembled into an evaporation device.
A Janus seesaw evaporator to leverage scaling for periodic self‐descaling is presented. Salt ions migrate toward the tilted end and the formed scaling triggers the evaporator to flip for scaling dissolution. The evaporator achieves an evaporation rate of up to 2.65 kg m−2 h−1 in an 8 wt.% NaCl solution and can maintain a stable evaporation rate over 120 h operation.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Designing nanocomposite hydrogels with oriented nanosheets has emerged as a promising toolkit to achieve preferential performances that go beyond their disordered counterparts. Although current ...fabrication strategies via electric/magnetic force fields have made remarkable achievements, they necessitate special properties of nanosheets and suffer from an inferior orientation degree of nanosheets. Herein, a facile and universal approach is discovered to elaborate MXene‐based nanocomposite hydrogels with highly oriented, heterogeneous architecture by virtue of supergravity to replace conventional force fields. The key to such architecture is to leverage bidirectional, force‐tunable attributes of supergravity containing coupled orthogonal shear and centrifugal force field for steering high‐efficient movement, pre‐orientation, and stacking of MXene nanosheets in the bottom. Such a synergetic effect allows for yielding heterogeneous nanocomposite hydrogels with a high‐orientation MXene‐rich layer (orientation degree, f = 0.83) and a polymer‐rich layer. The authors demonstrate that MXene‐based nanocomposite hydrogels leverage their high‐orientation, heterogeneous architecture to deliver an extraordinary electromagnetic interference shielding effectiveness of 55.2 dB at 12.4 GHz yet using a super‐low MXene of 0.3 wt%, surpassing most hydrogels‐based electromagnetic shielding materials. This versatile supergravity‐steered strategy can be further extended to arbitrary nanosheets including MoS2, GO, and C3N4, offering a paradigm in the development of oriented nanocomposites.
A novel supergravity‐steered approach is designed to manipulate the assembly of arbitrary nanosheets from MXene to MoS2, GO, and C3N4 for fabricating oriented nanocomposite hydrogels with heterogeneous architecture. The resultant MXene‐based nanocomposite hydrogels showcase an extraordinary electromagnetic interference shielding effectiveness (EMI SE) of 55.2 dB yet using a super‐low MXene of 0.3 wt%, surpassing most hydrogels‐based electromagnetic shielding materials.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Despite the great interest in carborane-containing molecules, there is a lack of literature on the generation of central chiralities,
catalytic asymmetric transformations using prochiral carboranyl ...substrates. Herein, we have synthesized novel optically active icosahedral carborane-containing diols
Sharpless catalytic asymmetric dihydroxylation of carborane-derived alkenes, under mild conditions. The reaction showed a good substrate scope with 74-94% yields and 92->99% ee. This synthetic approach facilitated the creation of two adjacent stereocenters respectively located at the α,β-position of
-carborane cage carbon, with a single
-diastereoisomer. In addition, the obtained chiral carborane-containing diol product can be transformed to cyclic sulfate and can subsequently undergo a nucleophilic substitution and reduction to obtain the unexpected
-carboranyl derivatives of chiral amino alcohols in the form of zwitterions.
The development of special organic materials that can absorb light energy in both UV-Vis and near-infrared (NIR) regions is significantly important for their appealing applications in highly ...efficient solar energy utilization. Herein, through introducing a vertically π-extended strong acceptor unit, the absorption maximum peaks of all three donor-acceptor polymers were pushed over 1000 nm. Polymer
E-DTP
showed an ultralow bandgap of 0.52 eV with an absorption tail extending beyond 2000 nm. Polymer
E-T
exhibited broad absorption covering the wavelength range from 300 to 1700 nm, which is basically consistent with the solar spectrum. Both
E-DTP
and
E-T
exhibit high photothermal conversion efficiencies under 1064 nm irradiation, 58.2% for the former and 50.3% for the latter, suggesting efficient NIR light utilization. Significantly, under one sunlight irradiation, high photothermal conversion with excellent photostability was also achieved for
E-T
. The excellent photothermal conversion ability of
E-T
is mainly attributed to the ultrafast internal conversion process (1.49 ps). Through simply dip-coating oil-soluble
E-T
on the top of a hydrophilic melamine sponge (MFS) as photothermal materials, a Janus evaporator could be easily constructed. Such evaporator exhibited a high water evaporation rate of 2.10 kg m
−2
h
−1
with a remarkable solar-to-vapor efficiency of 86.9% under 1 sun irradiation, showing the purification ability of multiple waste waters (seawater, microorganism and organic dyes contaminated waters). This study provides insight into the photothermal mechanism for ultralow bandgap organic materials and a guideline for the rational design of high-performance organic photothermal materials. Moreover, this work indicates the enormous prospects for the NIR polymer toward high performance solar thermal conversion.
A donor-acceptor polymer with broad absorption from 300 to 1700 nm as a photothermal material toward highly efficient solar-driven water evaporation.
Aim
To compare the pregnancy outcomes after day 5 blastocyst‐stage embryo transfers (BET) versus day 6 BET following vitrified‐warmed cycle and to evaluate whether the number of embryos transferred ...and the chromosomal status of embryo influence effect estimates.
Methods
A literature search (PubMed, Embase and MEDLINE) up to January 2019 was conducted to identify studies where women with day 6 BET were compared to women with day 5 BET. Only studies published in English language, on peer‐reviewed journal were considered eligible. The following subgroup analyses were performed: (i) number of embryos transferred and (ii) chromosomal status of embryo.
Results
From a total of 1956 articles identified, 23 observational studies were included in the meta‐analysis. We observed that day 6 BET were associated with lower implantation rate (risk ratio, RR: 1.17, 95% confidence interval, CI: 1.10–1.24), clinical pregnancy rate (RR: 1.17, 95% CI: 1.10–1.24), ongoing pregnancy rate (RR: 1.15, 95% CI: 1.07–1.24) and live birth rate (RR: 1.22, 95% CI: 1.11–1.33) than day 5 BET following vitrified‐warmed cycle. The subgroup analysis found that the superiority of day 5 BET compared with day 6 BET is influenced by the number of embryos transferred and chromosomal status of embryos.
Conclusion
Current evidence shows that day 5 BET is superior to day 6 BET following vitrified‐warmed cycle in clinical practice. Due to the overall low quality of available evidence, more larger and well‐conducted studies are needed to compare the pregnancy outcomes between day 5 and day 6 BET before drawing a clear conclusion.
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FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Our recent studies have identified that the red nucleus (RN) dual-directionally modulates the development and maintenance of mononeuropathic pain through secreting proinflammatory and ...anti-inflammatory cytokines. Here, we further explored the action of red nucleus IL-33 in the early development of mononeuropathic pain.
In this study, male rats with spared nerve injury (SNI) were used as mononeuropathic pain model. Immunohistochemistry, Western blotting, and behavioral testing were used to assess the expressions, cellular distributions, and actions of red nucleus IL-33 and its related downstream signaling molecules.
IL-33 and its receptor ST2 were constitutively expressed in the RN in naive rats. After SNI, both IL-33 and ST2 were upregulated significantly at 3 days and peaked at 1 week post-injury, especially in RN neurons, oligodendrocytes, and microglia. Blockade of red nucleus IL-33 with anti-IL-33 neutralizing antibody attenuated SNI-induced mononeuropathic pain, while intrarubral administration of exogenous IL-33 evoked mechanical hypersensitivity in naive rats. Red nucleus IL-33 generated an algesic effect in the early development of SNI-induced mononeuropathic pain through activating NF-κB, ERK, p38 MAPK, and JAK2/STAT3, suppression of NF-κB, ERK, p38 MAPK, and JAK2/STAT3 with corresponding inhibitors markedly attenuated SNI-induced mononeuropathic pain or IL-33-evoked mechanical hypersensitivity in naive rats. Red nucleus IL-33 contributed to SNI-induced mononeuropathic pain by stimulating TNF-α expression, which could be abolished by administration of inhibitors against ERK, p38 MAPK, and JAK2/STAT3, but not NF-κB.
These results suggest that red nucleus IL-33 facilitates the early development of mononeuropathic pain through activating NF-κB, ERK, p38 MAPK, and JAK2/STAT3. IL-33 mediates algesic effect partly by inducing TNF-α through activating ERK, p38 MAPK and JAK2/STAT3.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
We previously reported that interleukin (IL)‐6 in the red nucleus (RN) is involved in the maintenance of neuropathic pain induced by spared nerve injury (SNI), and exerts a facilitatory effect via ...Janus‐activated kinase 2/signal transducer and activator of transcription 3 (JAK2/STAT3) and extracellular signal‐regulated kinase (ERK) signal transduction pathways. The present study aimed at investigating the roles of tumor necrosis factor‐α (TNF‐α) and IL‐1β in RN IL‐6‐mediated maintenance of neuropathic pain and related signal transduction pathways. Being similar to the elevation of RN IL‐6 three weeks after SNI, increased protein levels of both TNF‐α and IL‐1β were also observed in the contralateral RN three weeks after the nerve injury. The upregulations of TNF‐α and IL‐1β were closely correlative with IL‐6 and suppressed by intrarubral injection of a neutralizing antibody against IL‐6. Administration of either the JAK2 antagonist AG490 or the ERK antagonist PD98059 to the RN of rats with SNI remarkably increased the paw withdrawal threshold (PWT) and inhibited the up‐regulations of local TNF‐α and IL‐1β. Further experiments indicated that intrarubral injection of exogenous IL‐6 in naive rats apparently lowered the PWT of the contralateral hindpaw and boosted the local expressions of TNF‐α and IL‐1β. Pretreatment with AG490 could block IL‐6‐induced tactile hypersensitivity and suppress the up‐regulations of both TNF‐α and IL‐1β. However, injection of PD98059 in advance only inhibited the upregulation of IL‐1β, but not TNF‐α. These findings indicate that RN IL‐6 mediates the maintenance of neuropathic pain by inducing the productions of TNF‐α and IL‐1β. IL‐6 induces the expression of TNF‐α through the JAK2/STAT3 pathway, and the production of IL‐1β through the JAK2/STAT3 and ERK pathways.
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BFBNIB, DOBA, FZAB, GIS, IJS, IZUM, KILJ, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBMB, UILJ, UKNU, UL, UM, UPUK
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