Covalent organic frameworks (COFs), as a class of crystalline porous polymers, featuring designable structures, tunable frameworks, well‐defined channels, and tailorable functionalities, have emerged ...as promising organic electrode materials for rechargeable metal‐ion batteries in recent years. Tremendous efforts have been devoted to improving the electrochemical performance of COFs. However, although significant achievements have been made, the electrochemical behaviors of developed COFs are far away from the desirable performance for practical batteries owing to intrinsic problems, such as poor electronic conductivity, the trade‐off relationship between capacity and redox potential, and unfavorable micromorphology. In this review, the recent progress in the development of COFs for rechargeable metal‐ion batteries is presented, including Li, Na, K, and Zn ion batteries. Various research strategies for improving the electrochemical performance of COFs are summarized in terms of the molecular‐level design and the material‐level modification. Finally, the major challenges and perspectives of COFs are also discussed in the aspect of large‐scale production and electrochemical performance improvements.
Covalent organic frameworks (COFs), as a class of crystalline porous polymers, have emerged as promising organic electrode materials for rechargeable metal‐ion batteries in recent years. Here we summarize the latest progress of COFs in Li, Na, K, and Zn ion batteries, and discuss various research strategies, major challenges, and perspectives.
Organic cathode materials for lithium storage have attracted wide attention owing to their very diverse structures and largely tuned engineered molecular levels. However, it remains a great challenge ...to design a cathode material with simultaneously combined features of high specific capacity, cycle life and rate performance. Here, based on our proposed strategy, we design and report a BQ1-COF consisting of maximum active groups (C=O and C=N) with minimal inactive groups, which when used as cathode materials for lithium-ion batteries give a reversible capacity of 502.4 mA h g−1 at 0.05C, so far the highest capacity among polymer-based cathode materials. More importantly, the stable framework structure delivers an excellent capacity retention (81% after 1,000 cycles at 1.54 A g−1), and it is noted that the rate performance (170.7 mA h g−1 even at 7.73 A g−1) is far superior to previous related reports. These results indicate that maximizing the loading of redox active groups in a stable network structure is an effective strategy to design organic cathode materials simultaneously with high capacity and outstanding cycle and rate performance for next generation lithium-ion batteries.
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•A strategy for the design of LIB cathode materials with overall high performance is proposed.•BQ1-COF delivers the highest capacity among polymer-based cathode materials so far in literatures.•The stable structure of BQ1-COF affords an excellent cycle performance.•The rate performance (170.7 mA h g−1 even at 7.73 A g−1) is far superior to previous related reports.
Identification of humic-like substances (HULIS) structures and components is still a major challenge owing to their chemical complexity. This study first employed a complementary method with the ...combination of two-dimensional gas chromatography–time-of-flight mass spectrometry and liquid chromatography–quadrupole-time-of-flight mass spectrometry to address low-polarity and polar components of HULIS in PM2.5 (particulate matter with an aerodynamic diameter less than 2.5 μm), respectively. The combination method showed a significant correlation in identifying overlapping species and performed well in uncovering the chemical complexity of HULIS. A total of 1246 compound species in HULIS (65.6–81.0% for each sample), approximately 1 order of magnitude more compounds than that reported in previous studies, were addressed in PM2.5 collected in real-world household biomass and coal combustion. Aromatics were the most abundant compounds (37.4–64.1% in biomass and 34.5–70.0% in coal samples) of the total mass in all HULIS samples according to carbon skeleton determination, while the major components included phenols (2.6–21.1%), ketones (6.0–17.1%), aldehydes (1.1–6.8%), esters (2.9–20.0%), amines/amides (3.2–8.5%), alcohols (3.8–17.0%), and acids (4.7–15.1%). Among the identified HULIS species, 11–36% mass in biomass and 11–41% in coal were chromophores, while another 22–35 and 23–29% mass were chromophore precursors, respectively. The combination method shows promise for uncovering HULIS fingerprinting.
The two-stage cultivation system is widely employed for natural astaxanthin production using Haematococcus pluvialis, but the high biomass concentration of green vegetative cells (GVCs) is often ...difficult to achieve and little has been known about the combined photoinduction effect of light path (LP, inner diameter of 3 cm or 6 cm) and illumination mode (IM, unilateral or bilateral high light illumination). On the basis of isolating an excellent astaxanthin-producing algal strain (named H. pluvialis JNU35) and the optimized nutrient conditions, this study innovatively investigated the combined effect of LP and IM on biomass and astaxanthin hyper-production by this isolate. As a result, H. pluvialis JNU35 exhibited an ultrahigh biomass concentration of 20.1 ± 0.2 g/L and astaxanthin productivity of 18.1 mg/L/d under an optimum photoinduction combination (6 cm LP in the green stage, 3 cm LP in the red stage with bilateral high light illumination) in column photobioreactors. Moreover, an appropriate phase of GVCs being transferred into the red inductive stage was also determined to further increase the biomass concentration to 27.3 ± 0.6 g/L. By combining above optimal culture conditions, a novel culture strategy for enhancing astaxanthin production was proposed and validated in a flat-plate photobioreactor, which achieved a significant amount of astaxatnthin (5.6%, wt%) and a higher biomass concentration (3.0 g/L). This novel strategy will provide a technical solution for high-titer astaxanthin production from H. pluvialis for industrial scale.
•A newly isolated hyper astaxanthin-producing strain of H. pluvialis was identified.•The combined effects of light path and illumination mode were first reported.•An appropriate green vegetative phase resulted in an ultrahigh biomass accumulation.•Higher astaxanthin content (5.61%, wt%) was achieved form mini-pilot scale culture.•A novel strategy for enhancing astaxanthin production of H. pluvialis was proposed.
Transient transformation is simpler, more efficient and economical in analyzing protein subcellular localization than stable transformation. Fluorescent fusion proteins were often used in transient ...transformation to follow the in vivo behavior of proteins. Onion epidermis, which has large, living and transparent cells in a monolayer, is suitable to visualize fluorescent fusion proteins. The often used transient transformation methods included particle bombardment, protoplast transfection and Agrobacterium-mediated transformation. Particle bombardment in onion epidermis was successfully established, however, it was expensive, biolistic equipment dependent and with low transformation efficiency. We developed a highly efficient in planta transient transformation method in onion epidermis by using a special agroinfiltration method, which could be fulfilled within 5 days from the pretreatment of onion bulb to the best time-point for analyzing gene expression. The transformation conditions were optimized to achieve 43.87% transformation efficiency in living onion epidermis. The developed method has advantages in cost, time-consuming, equipment dependency and transformation efficiency in contrast with those methods of particle bombardment in onion epidermal cells, protoplast transfection and Agrobacterium-mediated transient transformation in leaf epidermal cells of other plants. It will facilitate the analysis of protein subcellular localization on a large scale.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Abstract
Exploring the dynamic structural evolution of electrocatalysts during reactions represents a fundamental objective in the realm of electrocatalytic mechanism research. In pursuit of this ...objective, we synthesized PhenPtCl
2
nanosheets, revealing a N
2
-Pt-Cl
2
coordination structure through various characterization techniques. Remarkably, the electrocatalytic performance of these PhenPtCl
2
nanosheets for hydrogen evolution reaction (HER) surpasses that of the commercial Pt/C catalyst across the entire pH range. Furthermore, our discovery of the dynamic coordination changes occurring in the N
2
-Pt-Cl
2
active sites during the electrocatalytic process, as clarified through in situ Raman and X-ray photoelectron spectroscopy, is particularly noteworthy. These changes transition from Phen-Pt-Cl
2
to Phen-Pt-Cl and ultimately to Phen-Pt. The Phen-Pt intermediate plays a pivotal role in the electrocatalytic HER, dynamically coordinating with Cl
-
ions in the electrolyte. Additionally, the unsaturated, two-coordinated Pt within Phen-Pt provides additional space and electrons to enhance both H
+
adsorption and H
2
evolution. This research illuminates the intricate dynamic coordination evolution and structural adaptability of PhenPtCl
2
nanosheets, firmly establishing them as a promising candidate for efficient and tunable electrocatalysts.
In this work, we analyzed freshly emitted particles from ship exhaust in the Guangzhou port region before and after the implementation of a clean fuel policy. We used a single particle aerosol mass ...spectrometer (SPAMS) to measure the changes in the chemical compositions of single particles and evaluate the role of V as a tracer for ship emissions. Particles from high sulfur fuel (SF) oil (HS) combustion ships consisted of 54.8% elemental carbon-vanadium-sulfate (EC-V-S) and 25.0% vanadium-sulfate (V-S) particles, while particles from low SF oil (LS) combustion ships were composed of 38.7% organic carbon-sulfate (OC-S) and 28.6% elemental and organic carbon (ECOC) particles. The sulfate-containing particles exhibited a moderate decrease from 95% in HS emissions to 78% in LS emissions, which still suggests the dominant role of sulfate in LS emissions after the implementation of a clean fuel policy. The V-containing particles showed a sharp decrease from 67% in HS emissions to 14% in LS emissions along with the decrease in the relative peak area (RPA) of V, suggesting a remarkable reduction in V in ship exhaust. The count of V-containing particles in urban Guangzhou in June 2017 was generally ten times lower than that in June 2016, which was in accordance with the sharp decrease in V-containing particles in LS emissions rather than in HS emissions. Despite the decrease in V in source-oriented ship emitted particles, the ubiquitous distribution of V in particles from lower SF combustion ships suggests V is still effective as a tracer of ship emissions in port regions after the implementation of the clean fuel policy. Furthermore, the particles from LS emissions were investigated in comparison to those from gasoline vehicles (GV), diesel vehicles (DV) and coal combustion (CC) sources to better resolve ship-related particles in port regions.
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•Freshly emitted single particles from ship exhaust in Guangzhou port before and after clean fuel policy were comparatively studied.•The ubiquitous distribution of V in particles from lower sulfur fuel (LS) combustion ships suggests V is still an effective tracer of ship emissions.•A moderate decrease of sulfate-containing particles in LS particles indicates the persistent dominance of sulfate in ship exhaust.
•MMP3 is upregulated in colon cancers.•Tumor cell-associated MMP3 expression is important for tumor growth.•The cancer therapy by MMP3 inhibition is improved together with oncolytic ...virus.•Downregulation of MMP3 reduces tumor cell invasion.•Erk1/2 and NF-κB signaling are changed by MMP3 downregulation.
In cancer, the extracellular matrix is extensively remodeled during chronic inflammation, thus affecting cell transcription, differentiation, migration and cell-cell interactions. Matrix metalloproteinases can degrade the extracellular matrix of tumor tissues and take important roles in disease progression. Numerous efforts to develop cancer treatments targeting matrix metalloproteinases have failed in clinical trials owing to the ineffectiveness and toxicity of the applied inhibitors. In this study, we investigated the potential of targeting matrix metalloproteinases and oncolytic virus combination in cancer therapy. We found that MMP3 expression was upregulated in various cancers and MMP3 expression in the tumor cells, but not in other tissues, was important for tumor growth and metastasis. Single treatment of colon cancer with multiple MMP3 inhibitors was not effective in mice. Nevertheless, the therapeutic effect of MMP3 was greatly improved by combination with an oncolytic virus. A potential mechanism of MMP3 in regulating tumor cell proliferation and invasion was mediated via Erk1/2 an NF-κB signaling. This study reveals that MMP3 is a promising target and the combined treatment with oncolytic virus is a potential strategy for cancer therapy.
To analyze the quantitative parameters acquired by optical coherence tomography angiography (OCTA) in patients with autoimmune posterior uveitis.
OCTA images of 65 eyes affected with uveitis and 65 ...normal control (NC) eyes were obtained. The central macular thickness (CMT), retinal thicknesses, foveal avascular zone (FAZ) area, foveal density 300 μm (FD300), and vascular density (VD) were compared among acute uveitic eyes, chronic uveitic eyes, and NC eyes. VDs were evaluated in the choriocapillaris, outer retina, optic disk, whole and parafovea superficial capillary plexus (SCP), and whole and parafovea deep capillary plexus (DCP). Correlation analysis was used to analyze the relationship between LogMAR best-corrected visual acuity (BCVA) and quantitative parameters from OCTA.
Compared with NC eyes, the CMT and retinal thicknesses were increased significantly in eyes with uveitis (
< 0.05, respectively). No significant difference was observed in the FAZ area. FD300, VDs in the optic disk, SCP, and DCP both in whole image and parafovea, choriocapillaris were significantly decreased in uveitis eyes (
< 0.05, respectively) compared with NC eyes, only the acute group had decreased VD of the outer retina and choriocapillaris compared with the NC group (
< 0.05). Moreover, quantitative parameters of OCTA showed a significant correlation with LogMAR BCVA in the patients with uveitis. Whole VD DCP was the best predictive factor for BCVA in the patients with uveitis.
Quantitative measurement by OCTA is a promising strategy for objective assessment of autoimmune posterior uveitis.
Molecular analysis of exhaled breath aerosol (EBA) with simple procedures represents a key step in clinical and point-of-care applications. Due to the crucial health role, a face mask now is a safety ...device that helps protect the wearer from breathing in hazardous particles such as bacteria and viruses in the air; thus exhaled breath is also blocked to congregate in the small space inside of the face mask. Therefore, direct sampling and analysis of trace constituents in EBA using a face mask can rapidly provide useful insights into human physiologic and pathological information. Herein, we introduce a simple approach to collect and analyze human EBA by combining a face mask with solid-phase microextraction (SPME) fiber. SPME fiber was inserted into a face mask to form SPME-in-mask that covered nose and mouth for in vivo sampling of EBA, and SPME fiber was then coupled with direct analysis in real-time mass spectrometry (DART-MS) to directly analyze the molecular compositions of EBA under ambient conditions. The applicability of SPME-in-mask was demonstrated by direct analysis of drugs and metabolites in oral and nasal EBA. The unique features of SPME-in-mask were also discussed. Our results showed that this method is enabled to analyze volatile and nonvolatile analytes in EBA and is expected to have a significant impact on human EBA analysis in clinical applications. We also hope this method will inspire biomarker screening of some respiratory diseases that usually required wearing of a face mask in daily life.
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