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Mutations in fibrillin 1 (FBN1) is the main cause of Marfan syndrome (MFS) with thoracic aortic aneurysm (TAA) as the main complication. Activation of the complement system plays a key role in the formation of thoracic and abdominal aortic aneurysms. However, the role of the complement system in MFS-associated aortic aneurysms remains unclear. In this study, we observed increased levels of complement C3a and C5a in the plasma of MFS patients and mouse, and the increased deposition of the activated complement system product C3b/iC3b was also observed in the elastic fiber rupture zone of 3-month-old MFS mice. The expression of C3a receptor (C3aR) was increased in MFS aortas, and recombinant C3a promoted the expression of cytokines in macrophages. The administration of a C3aR antagonist (C3aRA) attenuated the development of thoracic aortic aneurysms in MFS mice. The increased inflammation response and matrix metalloproteinases activities were also attenuated by C3aRA treatment in MFS mice. Therefore, these findings indicate that the complement C3a/C3aR inhibition alleviates the formation of aortic aneurysm in Marfan syndrome mice. [ABSTRACT FROM AUTHOR]

Background: Late-life depression (LLD) is characterized by disrupted brain networks. Resting-state networks in the brain are composed of both stable and transient topological structures known as microstates, which reflect the dynamics of the neural activities. However, the specific pattern of EEG microstate in LLD remains unclear. Methods: Resting-state EEG were recorded for 31 patients with episodic LLD (eLLD), 20 patients with remitted LLD (rLLD) and 32 healthy controls (HCs) using a 64-channel cap. The clinical data of the patients were collected and the 17-Item Hamilton Rating Scale for Depression (HAMD) was used for symptom assessment. Duration, occurrence, time coverage and syntax of the four microstate classes (A-D) were calculated. Group differences in EEG microstates and the relationship between microstates parameters and clinical features were analyzed. Results: Compared with NC and patients with rLLD, patients with eLLD showed increased duration and time coverage of microstate class D. Besides, a decrease in occurrence of microstate C and transition probability between microstate B and C was observed. In addition, the time coverage of microstate D was positively correlated with the total score of HAMD, core symptoms, and miscellaneous items. Conclusion: These findings suggest that disrupted EEG microstates may be associated with the pathophysiology of LLD and may serve as potential state markers for the monitoring of the disease. [ABSTRACT FROM AUTHOR]

Aqueous zinc ion batteries (AZIBs) are promising electrochemical energy storage devices due to their high theoretical specific capacity, low cost, and environmental friendliness. However, uncontrolled dendrite growth poses a serious threat to the reversibility of Zn plating/stripping, which impacts the stability of batteries. Therefore, controlling the disordered dendrite growth remains a considerable challenge in the development of AZIBs. Herein, a ZIF-8-derived ZnO/C/N composite (ZOCC) interface layer was constructed on the surface of the Zn anode. The homogeneous distribution of zincophilic ZnO and the N element in the ZOCC facilitates directional Zn deposition on the (002) crystal plane. Moreover, the conductive skeleton with a microporous structure accelerates Zn2+ transport kinetics, resulting in a reduction in polarization. As a result, the stability and electrochemical properties of AZIBs are improved. Specifically, the ZOCC@Zn symmetric cell sustains over 1150 h at 0.5 mA cm−2 with 0.25 mA h cm−2, while the ZOCC@Zn half-cell achieves an outstanding Coulombic efficiency of 99.79% over 2000 cycles. This work provides a simple and effective strategy for improving the lifespan of AZIBs. [ABSTRACT FROM AUTHOR]

Since the energy density and voltage window of supercapacitors cannot match that of lithium-ion batteries, supercapacitors are far from replacing batteries but can only be seen as a supplement to battery charge storage or transmission devices. The design of transition metal oxide-based electrodes with high cycling capacitance retention is very important for the development of supercapacitors. In this study, flower-like SAC@NiCoMn-LDH electrode materials with different Mn doping ratios were prepared by a hydrothermal method with mesoporous carbon (SAC) as the substrate. Density functional theory (DFT) calculations confirm that Mn doping can enhance the adsorption of OH− and the desorption of the H proton. In addition, Mn doping increases the density of states of LDH near the Fermi level and increases the number of active electrons, which is conducive to the occurrence of electrochemical reactions. In the three-electrode system, SAC@Ni2Co0.95Mn0.05-LDH with optimal doping ratio increased the specific capacitance by three times compared to that of NiCo-LDH and displayed an excellent cycling stability (83.76% capacitance retention after 50 000 cycles). Moreover, the prepared SAC@Ni2Co0.95Mn0.05-LDH and commercial activated carbon (AC) were made into electrode plates and then assembled into a SAC@Ni2Co0.95Mn0.05-LDH//AC asymmetric supercapacitor (ASC). The ASC exhibited high energy density (23.68 W h kg−1 at 325 W kg−1) and excellent specific capacitance retention (85.32% after 50 000 cycles), making it well suited for efficient wind energy storage and conversion with promising practical applications. [ABSTRACT FROM AUTHOR]

Recently, the development of composite materials composed of magnetic materials and MXene has attracted significant attention. However, the thickness and microwave absorption performance of the composite is still barely satisfactory. In this work, the C-N@NiFe2O4@MXene/Ni nanocomposites were successfully synthesized in situ by hydrothermal and calcination methods. Benefiting from the introduction of the carbon-nitrogen(C-N) network structure, the overall dielectric properties are improved effectively, consequently reducing the thickness of the composite while maintaining excellent absorption performance. As a result, the minimum reflection loss of C-N@NiFe2O4@MXene/Ni can reach −50.51 dB at 17.3 GHz at an ultralow thickness of 1.5 mm, with an effective absorption bandwidth of 4.95 GHz (13.02–18 GHz). This research provides a novel strategy for materials to maintain good absorption performance at an ultralow thickness level. [ABSTRACT FROM AUTHOR]

The pseudocapacitor material is easily decomposed when immersed in alkaline solution for a long time. Hence, it is necessary to find a strategy to improve the alkali stability of pseudocapacitor materials. In addition, the relationship between alkali stability and electrochemical performance is still unclear. In this work, a series of Al-based LDH (Layered double hydroxide) and derived Ni/Co-based sulfides are prepared, and corresponding alkali stability and electrochemical performance are analyzed. The alkali stability of CoAl LDH is so poor and can be improved effectively by doping of Ni. Ni1Co2S4 and Ni2Co1Al LDH exhibit an outstanding alkali stability, and Ni2Co1S4 exhibits an extremely poor alkali stability. The variable valence state of Co element and the solubility of Al in alkali solution are the fundamental reasons for the poor alkali stability of CoAl LDH and Ni2Co1S4. Ni2Co1S4 showed an outstanding electrochemical performance in a three-electrode system, which is better than that of Ni1Co2S4, indicating that there is no direct correlation between alkali stability and electrochemical properties. Sulfidation improved the electrical conductivity and electrochemical activity of electrode materials, whereas alkali etching suppressed the occurrence of the electrochemical reaction. Overall, this work provides a clear perspective to understand the relationship between alkali stability and electrochemical properties. [ABSTRACT FROM AUTHOR]

Reasonable structural design and composition control are the dominant factors for tuning the electromagnetic absorbing properties of materials. In this paper, microspheres composed of NiO, Ni, and Co3O4 nanoparticles (NCMO) were successfully synthesized using a mild oxidation method. Benefiting from the multi-component composition and a unique microstructure, the RLmin of CNMO can reach −46.8 dB at 17 GHz, with an effective absorption bandwidth of 4.1 GHz (13.9–18 GHz). The absorbing properties and the absorbing mechanism analysis showed that the microsphere-structured NCMO composed of multi-component nanoparticles enhanced the interface polarization, thereby improving the absorption performance. This research provides a new avenue for MOF-derived oxide materials with excellent electromagnetic wave absorbing properties. [ABSTRACT FROM AUTHOR]

Efficient low‐temperature hydrodeoxygenation (HDO) of lignin derivatives to produce biofuels and high value‐added chemicals is still of challenge. Here, we have constructed a high active and stable 0.2 wt.% Pd/MS‐HZSM‐5(30) catalyst, and 94.7 % yield of 2‐methoxy‐4‐methylphenol (MMP) can be achieved in HDO of vanillin (VAN, a typical platform molecule of lignin derivatives) under milder reaction conditions (60 °C, 5 h, molar ratio of VAN/Pd=1200, water phase), outperforming the most works reported recently. Detailed experimental and mechanistic studies demonstrated that the superior catalytic performance was due to the rapid hydrogenolysis of generated intermediate (vanillyl alcohol, VAL) to MMP proceeded in an interfacial microenvironmental created by Pd NPs and acidic sites in Pd/MS‐HZSM‐5(30). These new insights will provide potential guidance for the efficient low‐temperature production of biofuels and valuable chemicals from lignin derivatives or raw lignin. [ABSTRACT FROM AUTHOR]

Considering the electromagnetic protection needs of important ground buildings, exploring the electromagnetic wave (EMW) absorption performance of manganese ore powder (MOP) building materials is an effective way to overcome its low added value and difficulty in popularizing. Here, choosing filling ratios commonly used in building materials such as autoclaved bricks, MOP/paraffin samples with 20%, 40%, and 60% mass fraction of MOP were prepared, and electromagnetic properties were analyzed at 2–18 GHz using the coaxial method. The results show that 60 wt% sample has the best absorption performance, with a minimum reflection loss (RLmin) value of −22.06 dB at 15.04 GHz, and the effective absorption bandwidth (EAB, RL < −10 dB) reaches 4.16 GHz at a 7.65 mm absorber thickness, covering most of the Ku-band region. The excellent microwave absorption performance of MOP is due to its multi-oxide forming multi-interface structure and rough surface, which can not only form abundant dipole and interfacial polarization under the action of EMW, but also reflect and scatter the incident EMW, prolong the transmission path, and enhanced the absorption of microwaves. This study demonstrates that MOP building materials can have excellent microwave absorption properties, thus becoming a new way to address harmful manganese residue; for example, autoclaved bricks, which can not only improve the added value of manganese residue building materials but also can be consumed on a large scale. It provides a new idea to solve the harm of manganese residue. [ABSTRACT FROM AUTHOR]

Metal–organic frameworks (MOFs) with a high density of metal nodes have great potential in the application of heterogeneous catalysis. However, identifying the real active site in MOF structures and tuning its amount to further improve its catalytic performance are still a great challenge. In this paper, defective UiO-66 modulated with trifluoroacetic acid (TFA) was synthesized and used for the conversion of cyclohexanone to cyclohexanol via hydrogen transfer. We found that not all structural defects were responsible for catalytic reaction, and only structural defects where open metal sites are created by a modulator were effective for cyclohexanone conversion. Then we successfully tuned the number of each type of effective structural defect (that is, missing-cluster defects or missing-linker defects) in modulated UiO-66 via precise control of the synthetic/treatment conditions. Our experimental results showed that the creation of both types of structural defects can increase the amount of effective open metal sites and then enhance their catalytic performances under the same conditions. Furthermore, the mechanism study confirmed that this reaction indeed proceeded on effective open metal sites. Our findings have further deepened the understanding of the roles of structural defects in MOF heterogeneous catalysis. [ABSTRACT FROM AUTHOR]

• The GaSb-microfiber saturable absorber is prepared using the magnetron sputtering deposition technique. • The maximum single pulse energy is 233.67 nJ. • The highest average output power is 21.8 mW. In this study, we report the use of GaSb as a saturable absorber (SA) material in an Er-doped fiber (EDF) laser. The GaSb-based SA is prepared through the magnetron sputtering deposition technology, wherein a thin GaSb film is deposited on a microfiber. The modulation depth, saturable intensity, and non-saturable loss of the SA are determined to be 5.45 %, 37.3 MW/cm2, and 29.12 %, respectively. Under the Q-switching working state, the repetition frequeny is tuned from 73.15 to 93.7 kHz, and the pulse duration is changed from 5.17 to 2.33 μs at a pumping power of 310 to 500 mW. The highest average output power is 21.8 mW, which corresponds to a single pulse energy of 233.67 nJ. The generated laser pulses are in a stable state with a signal to noise ratio (SNR) of 65 dB. These results confirm the potential of GaSb as a successful saturable absorber candiatiate for building pulsed fiber lasers and in ultrafast optics applications. [ABSTRACT FROM AUTHOR]

Continuous ZIF-67 polycrystalline membranes with effective propylene/propane separation performances were successfully fabricated through the incorporation of zinc ions into the ZIF-67 framework. The separation factor increases from 1.4 for the pure ZIF-67 membrane to 50.5 for the 90% zinc-substituted ZIF-67 membrane. [ABSTRACT FROM AUTHOR]

We report on the storage capacity and separation selectivity of an rht-type metal-organic framework, Cu -- TDPAT [TDPAT = 2,4,6-tris(3,5-dicarboxylphenylamino)-1,3,5-triazine], for C2 hydrocarbons over CH4. Henry's constant, the isosteric heat of adsorption and the ideal adsorbed solution theory selectivity were calculated based on single-component sorption isotherms. Theoretical calculations indicate that both the open metal sites and the Lewis basic sites have strong interactions with the C2 molecules. The combination of these two kinds of sites lead to the highest C2H2-CH4 selectivity of 127.1 as well as record high values for C2H4 adsorption enthalpies. To mimic real-world conditions, breakthrough experiments were conducted on an equimolar four-component mixture containing C2H2, C2H4, C2H6 and CH4 at room temperature and 1 atm pressure. Our results show that Cu-TDPAT is a promising candidate for CH4 capture and purification. [ABSTRACT FROM AUTHOR]

The porous and biomimetic cobalt silicate@diatomite (Co2SiO4@diatomite) was successfully synthesized by a two-step method, including the hydrothermal method and calcination to improve the electromagnetic wave absorption property. Different hydrothermal times were well-tuned for Co2SiO4@diatomite composites with different loadings of Co2SiO4. Interestingly, the Co2SiO4@diatomite composites (6 h, 25 wt%) had a smaller minimum reflection loss. Moreover, the minimum reflection loss (RLmin) could reach −12.03 dB at 16.64 GHz and the matched absorber thickness was 10 mm, while the effective absorption bandwidth (EAB, RL ≤ −10 dB) could be 1.92 GHz. In principle, such findings indicate that Co2SiO4@diatomite nanocomposites could be a promising candidate for high-efficiency microwave absorption capability. [ABSTRACT FROM AUTHOR]

In this study, moisture content, textural properties, microstructure, free sulfhydryl group content, the secondary structure of heat-induced duck egg white gels (DEWG) under different heating temperatures of 80 °C, 90 °C, 100 °C and times of 10, 15, 20, and 25 min were investigated. Enzymolysis efficiency and peptide mapping were determined to clarify the linkage mechanism in gel properties, digestion behavior and peptide release of DEWG. Results indicated that with the increasing temperature and time, a gel with harder texture and less moisture was formed. Related gel exhibited a more compact form of aggregation in the environmental scanning electron microscopy (ESEM) and transmission electron microscope (TEM), as well as an increase in the amount of free sulfhydryl group and β -sheet. The in vitro digestibility and the number of peptides produced were affected by protein aggregation morphology. The gel with low induction temperature and shorter induction time showed a loose structure, resulting in a higher digestibility and more quantity of peptides released. In conclusion, heat induced changes in gelation behavior of duck egg white protein, and thus exhibited critical effects on protein digestion and peptide released. • Gelation, digestion and peptide of heat-induced duck egg white were clarified. • Heat induction affects the digestibility by regulating the form of aggregates. • The gel springing did not rely on induction temperatures or time. • Overheat treatment reduced the digestibility of the gel. [ABSTRACT FROM AUTHOR]

In this work, spherical flower-shaped composite carbonyl iron powder@MnO2 (CIP@MnO2) with CIP as the core and ultrathin MnO2 nanosheets as the shell was successfully prepared by a simple redox reaction to improve oxidation resistance and electromagnetic wave absorption properties. The microwave-absorbing properties of CIP@MnO2 composites with different filling ratios (mass fractions of 20%, 40%, and 60% after mixing with paraffin) were tested and analyzed. The experimental results show that compared with pure CIP, the CIP@MnO2 composites have smaller minimum reflection loss and a wider effective absorption bandwidth than CIP (RL < −20 dB). The sample filled with 40 wt% has the best comprehensive performance, the minimum reflection loss is −63.87 dB at 6.32 GHz, and the effective absorption bandwidth (RL < −20 dB) reaches 7.28 GHz in the range of 5.92 GHz–9.28 GHz and 11.2 GHz–15.12 GHz, which covers most C and X bands. Such excellent microwave absorption performance of the spherical flower-like CIP@MnO2 composites is attributed to the combined effect of multiple beneficial components and the electromagnetic attenuation ability generated by the special spherical flower-like structure. Furthermore, this spherical flower-like core–shell shape aids in the creation of discontinuous networks, which improve microwave incidence dispersion, polarize more interfacial charges, and allow electromagnetic wave absorption. In theory, this research could lead to a simple and efficient process for producing spherical flower-shaped CIP@MnO2 composites with high absorption, a wide band, and oxidation resistance for a wide range of applications. [ABSTRACT FROM AUTHOR]

Aim Methods Results Conclusions Chemosensory anhedonia refers to the lack of hedonic ability to experience pleasure through the senses of smell and taste, which reduces the pleasure and comfort of food, and increases the risk of nutritional and immune deficiencies. However, there is no direct scientific evidence regarding chemosensory anhedonia in patients with late‐life depression (LLD). The aim of this study was to investigate chemosensory anhedonia in patients with LLD, and its potential association with depressive symptoms and cognitive function.A total of 114 patients with LLD and 92 normal controls were included in this study. They experienced clinical assessment, Chemosensory Pleasure Scale assessment, 17‐item Hamilton Depression Rating Scale assessment and cognitive assessments, which contain the Verbal Fluency Test. The associations between chemosensory pleasure and depressive symptoms or cognitive function in patients with LLD were explored using partial correlation analysis and mediation analysis.The Chemosensory Pleasure Scale scores were lower in the LLD group than in the normal control group, and were negatively correlated with the total scores and factors' scores (retardation, cognitive bias and anxiety/somatization) of the 17‐item Hamilton Depression Rating Scale, and positively correlated with the Verbal Fluency Test scores. The scores for the Food and Imagination dimensions of the Chemosensory Pleasure Scale showed partial mediating effects on the differences in Cognitive bias (a factor of the 17‐item Hamilton Depression Rating Scale) between patients with LLD and normal controls.Patients with LLD showed significant chemosensory anhedonia, and both depressive symptoms and cognitive impairment were associated with the severity of chemosensory anhedonia. Enhancing chemosensory pleasure in patients with LLD could potentially ameliorate their depressive symptoms. Geriatr Gerontol Int 2024; ••: ••–••. [ABSTRACT FROM AUTHOR]

BACKGROUND General paresis of the insane (GPI) is characterized by cognitive impairment, neuropsychiatric symptoms, and brain structural abnormalities, mimicking many neuropsychiatric diseases. Olfactory dysfunction has been linked to cognitive decline and neuropsychiatric symptoms in numerous neuropsychiatric diseases. Nevertheless, it remains unclear whether patients with GPI experience olfactory dysfunction and whether olfactory dysfunction is associated with their clinical manifestations. MATERIAL AND METHODS Forty patients with GPI and 37 healthy controls (HCs) underwent the "Sniffin Sticks" test battery, Mini-Mental State Examination, and Neuropsychiatric Inventory to measure olfactory function, cognitive function, and neuropsychiatric symptoms, respectively. Brain structural abnormalities were evaluated using visual assessment scales including the medial temporal lobe atrophy (MTA) visual rating scale and Fazekas scale. RESULTS Compared with HCs, patients with GPI exhibited significant olfactory dysfunction, as indicated by deficits in the odor threshold (OT) (P=0.001), odor discrimination (OD) (P<0.001), and odor identification (OI) (P<0.001). In patients with GPI, the OI was positively correlated with cognitive function (r=0.57, P<0.001), but no significant correlation was found between olfactory function and neuropsychiatric symptoms, blood, or cerebrospinal fluid biomarkers (rapid plasma reagin circle card test and Treponema pallidum particle agglutination test), or brain structural abnormalities (MTA and Fazekas scale scores). Mediation analysis indicated that the impaired OI in patients with GPI was mediated by cognitive impairment and impaired OT respectively. CONCLUSIONS Patients with GPI exhibited overall olfactory dysfunction. OI is correlated with cognitive function and the impaired OI is mediated by cognitive impairment in patients with GPI. Thus, OI may serve as a marker for reflecting cognitive function in patients with GPI.

Head and neck squamous cell carcinoma (HNSCC) is the sixth most common malignant tumor worldwide. Considering its special anatomical site and the progressive resistance to chemotherapy drugs, the development of more effective, minimally invasive and precise treatment methods is urgently needed. Nanomaterials, given their special properties, can be used as drug carrier systems to improve the therapeutic effect and reduce the adverse effects. The drug carrier systems with photothermal effect can promote the killing of cancer cells and help overcome drug resistance through heat stress. We selected dopamine, a simple raw material, and designed and synthesized three different configurations of nano-polydopamine (nPDA) nanomaterials, including nPDA balls, nPDA plates and porous nPDA balls. In addition to the self-polymerization and self-assembly, nPDA has high photothermal conversion efficiency and can be easily modified. Moreover, we loaded cisplatin into three different configurations of nPDA, creating nPDA-cis (the nano-drug carrier system with cisplatin), and comparatively studied the properties and antitumor effects of all the nPDA and nPDA-cis materials in vitro and nPDA-cis in vivo . We found that the photothermal effect of the nPDA-cis balls drug carrier system had synergistic effect with cisplatin, resulting in excellent antitumor effect and good clinical application prospects. The comparison of the three different configurations of drug carrier systems suggested the importance of optimizing the spatial configuration design and examining the physical and chemical properties in the future development of nano-drug carrier systems. In this study, we also noted the duality and complexity of the influences of heat stress on tumors in vitro and in vivo . The specific mechanisms and the synergy with chemotherapy and immunotherapy will be an important research direction in the future., (© The Author(s) 2024. Published by Oxford University Press.)

Recently, the development of composite materials composed of magnetic materials and MXene has attracted significant attention. However, the thickness and microwave absorption performance of the composite is still barely satisfactory. In this work, the C-N@NiFe 2 O 4 @MXene/Ni nanocomposites were successfully synthesized in situ by hydrothermal and calcination methods. Benefiting from the introduction of the carbon-nitrogen(C-N) network structure, the overall dielectric properties are improved effectively, consequently reducing the thickness of the composite while maintaining excellent absorption performance. As a result, the minimum reflection loss of C-N@NiFe 2 O 4 @MXene/Ni can reach -50.51 dB at 17.3 GHz at an ultralow thickness of 1.5 mm, with an effective absorption bandwidth of 4.95 GHz (13.02-18 GHz). This research provides a novel strategy for materials to maintain good absorption performance at an ultralow thickness level.

Based on the dual-resonance principle around the dispersion turning point, a scheme of chiral long-period fiber gratings (CLPGs) formed by twisting a high-birefringence (Hi-Bi) fiber is herein proposed to realise ultra-broadband flat-top circular polarizers. The coupling bandwidth is approximately seven times larger than that of traditional CLPGs. In addition, by introducing chirp characteristics in these CLPGs, an ultra-broadband flat-top circular polarizer with ∼200 nm@3 dB was conveniently achieved. Subsequently, by optimising the chirped CLPGs, a circular polarizer with a bandwidth extinction ratio of approximately 30 dB and a high level of ∼100 nm at 1 dB was realised. It was shown that the mode-controlling performances of the CLPGs can be remarkably improved, which has significant applications in light-field regulation. Finally, for the first time, it was proved that the CLPG cannot generate a vortex beam.

In this work, spherical flower-shaped composite carbonyl iron powder@MnO 2 (CIP@MnO 2 ) with CIP as the core and ultrathin MnO 2 nanosheets as the shell was successfully prepared by a simple redox reaction to improve oxidation resistance and electromagnetic wave absorption properties. The microwave-absorbing properties of CIP@MnO 2 composites with different filling ratios (mass fractions of 20%, 40%, and 60% after mixing with paraffin) were tested and analyzed. The experimental results show that compared with pure CIP, the CIP@MnO 2 composites have smaller minimum reflection loss and a wider effective absorption bandwidth than CIP (RL < -20 dB). The sample filled with 40 wt% has the best comprehensive performance, the minimum reflection loss is -63.87 dB at 6.32 GHz, and the effective absorption bandwidth (RL < -20 dB) reaches 7.28 GHz in the range of 5.92 GHz-9.28 GHz and 11.2 GHz-15.12 GHz, which covers most C and X bands. Such excellent microwave absorption performance of the spherical flower-like CIP@MnO 2 composites is attributed to the combined effect of multiple beneficial components and the electromagnetic attenuation ability generated by the special spherical flower-like structure. Furthermore, this spherical flower-like core-shell shape aids in the creation of discontinuous networks, which improve microwave incidence dispersion, polarize more interfacial charges, and allow electromagnetic wave absorption. In theory, this research could lead to a simple and efficient process for producing spherical flower-shaped CIP@MnO 2 composites with high absorption, a wide band, and oxidation resistance for a wide range of applications.

Oxide-/hydroxide-derived copper electrodes exhibit excellent selectivity toward C 2+ products during the electrocatalytic CO 2 reduction reaction (CO 2 RR). However, the origin of such enhanced selectivity remains controversial. Here, we prepared two Cu-based electrodes with mixed oxidation states, namely, HQ-Cu (containing Cu, Cu 2 O, CuO) and AN-Cu (containing Cu, Cu(OH) 2 ). We extracted an ultrathin specimen from the electrodes using a focused ion beam to investigate the distribution and evolution of various Cu species by electron microscopy and electron energy loss spectroscopy. We found that at the steady stage of the CO 2 RR, the electrodes have all been reduced to Cu 0 , regardless of the initial states, suggesting that the high C 2+ selectivities are not associated with specific oxidation states of Cu. We verified this conclusion by control experiments in which HQ-Cu and AN-Cu were pretreated to fully reduce oxides/hydroxides to Cu 0 , and the pretreated electrodes showed even higher C 2+ selectivity compared with their unpretreated counterparts. We observed that the oxide/hydroxide crystals in HQ-Cu and AN-Cu were fragmented into nanosized irregular Cu grains under the applied negative potentials. Such a fragmentation process, which is the consequence of an oxidation-reduction cycle and does not occur in electropolished Cu, not only built an intricate network of grain boundaries but also exposed a variety of high-index facets. These two features greatly facilitated the C-C coupling, thus accounting for the enhanced C 2+ selectivity. Our work demonstrates that the use of advanced characterization techniques enables investigating the structural and chemical states of electrodes in unprecedented detail to gain new insights into a widely studied system.

A novel tetraphenylethylene-based ladder network (MP1) made by polycondensation reaction from 4,4',4″,4‴-(ethene-1,1,2,2-tetrayl)tetrakis(benzene-1,2-diol) and 2,3,5,6-tetrafluoroterephthalonitrile and its COOH-functionalized analogue (MP2) were synthesized for the first time. Their structures were confirmed by solid-state nuclear magnetic resonance ( 13 C cross-polarization magic angle spinning), Fourier transform infrared spectroscopy, and elementary analysis. MP1 exhibited a high Brunauer-Emmett-Teller surface area (1020 m 2 g -1 ), whereas the COOH-functionalized MP2 showed a much smaller surface area (150 m 2 g -1 ) but displayed a more uniform pore size distribution. Because of the high density of nitrile groups in the network polymers of intrinsic microporosity (PIMs) and strong interaction with quadrupole CO 2 molecules, MP1 exhibited a high CO 2 adsorption capacity of 4.2 mmol g -1 at 273 K, combined with an isosteric heat of adsorption ( Q st ) of 29.6 kJ mol -1 . The COOH-functionalized MP2 showed higher Q st of 34.2 kJ mol -1 coupled with a modest CO 2 adsorption capacity of 2.2 mmol g -1 . Both network PIMs displayed high theoretical ideal adsorbed solution theory CO 2 /N 2 selectivities (51 and 94 at 273 K vs 34 and 84 at 298 K for MP1 and MP2, respectively). The high selectivities of MP1 and MP2 were confirmed by experimental column breakthrough experiments with CO 2 /N 2 selectivity values of 23 and 45, respectively. Besides the promising CO 2 capture and CO 2 /N 2 selectivity properties, MP1 also demonstrated high sorption capacity for toxic volatile organic vapors. At 298 K and a relative pressure of 0.95, benzene and toluene sorption uptakes reached 765 and 1041 mg g -1 , respectively. Moreover, MP1 also demonstrated some potential for adsorptive separation of xylene isomers with adsorptive selectivity of 1.75 for m -xylene/ o -xylene., Competing Interests: The authors declare no competing financial interest.

Metal-organic frameworks (MOFs) are crystalline porous materials with designable topology, porosity and functionality, having promising applications in gas storage and separation, ion conduction and catalysis. It is challenging to observe MOFs with transmission electron microscopy (TEM) due to the extreme instability of MOFs upon electron beam irradiation. Here, we use a direct-detection electron-counting camera to acquire TEM images of the MOF ZIF-8 with an ultralow dose of 4.1 electrons per square ångström to retain the structural integrity. The obtained image involves structural information transferred up to 2.1 Å, allowing the resolution of individual atomic columns of Zn and organic linkers in the framework. Furthermore, TEM reveals important local structural features of ZIF-8 crystals that cannot be identified by diffraction techniques, including armchair-type surface terminations and coherent interfaces between assembled crystals. These observations allow us to understand how ZIF-8 crystals self-assemble and the subsequent influence of interfacial cavities on mass transport of guest molecules.

In this work, we demonstrate for the first time the introduction of π-complexation into a porous aromatic framework (PAF), affording significant increase in ethylene uptake capacity, as illustrated in the context of Ag(I) ion functionalized PAF-1, PAF-1-SO3Ag. IAST calculations using single-component-isotherm data and an equimolar ethylene/ethane ratio at 296 K reveal that PAF-1-SO3Ag shows exceptionally high ethylene/ethane adsorption selectivity (Sads: 27 to 125), far surpassing benchmark zeolite and any other MOF reported in literature. The formation of π-complexation between ethylene molecules and Ag(I) ions in PAF-1-SO3Ag has been evidenced by the high isosteric heats of adsorption of C2H4 and also proved by in situ IR spectroscopy studies. Transient breakthrough experiments, supported by simulations, indicate the feasibility of PAF-1-SO3Ag for producing 99.95%+ pure C2H4 in a Pressure Swing Adsorption operation. Our work herein thus suggests a new perspective to functionalizing PAFs and other types of advanced porous materials for highly selective adsorption of ethylene over ethane.