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1.
Arch Med Sci ; 20(2): 655-663, 2024.
Article in English | MEDLINE | ID: mdl-38757011

ABSTRACT

Introduction: Chronic heart failure (CHF) is a leading cause of deaths induced by cardiovascular disease. This study aimed to investigate the protective effects of emodin in CHF rats and explore the related mechanisms. Material and methods: A total of 56 Wistar rats were used to construct CHF model using the coronary artery ligation. The effects of emodin on cardiac function and inflammation were analyzed in the CHF rats. Expression of miR-26b-5p in the CHF model before and after emodin treatment was estimated by quantitative real-time polymerase chain reaction. The effects of miR-26b-5p on cardiac function and inflammation were also assessed, and its target gene was predicted and confirmed in rat cardiomyocyte H9c2. Results: Emodin treatment could significant improve the cardiac function and inflammation evidenced by the increased increased ejection fraction (EF), fractional shortening (FS), left ventricular systolic pressure (LVSP) and maximum of the first differentiation of left ventricular pressure (+LV dP/dtmax) and decreased atrial natriuretic peptide (ANP), brain natriuretic peptide (BNP), left ventricular end diastolic pressure (LVEDP), interleukin (IL)-6, tumor necrosis factor α (TNF-α) levels. Expression of miR-26b-5p was downregulated in the CHF rats (CHF 0.442 ±0.131 vs. Sham 1.044 ±0.160), and this suppressive effect was rescued by emodin (Emodin 0.902 ±0.132 vs. CHF 0.442 ±0.131). The overexpression of miR-26b-5p in CHF rats led to improved cardiac function and inflammatory response. In addition, the emodin-induced increased EF, FS, LVSP and +LV dP/dtmax and decreased ANP, BNP, LVEDP, IL-6 and TNF-α were all abrogated by the knockdown of miR-26b-5p. The target prediction results revealed that PTEN was a target gene of miR-26b-5p in H9c2 cells. Conclusions: All the results indicated that emodin serves a protective role in CHF via regulation of the miR-26b-5p/PTEN pathway. Emodin may be an effective therapeutic agent for CHF treatment.

2.
Nat Commun ; 15(1): 3218, 2024 Apr 15.
Article in English | MEDLINE | ID: mdl-38622151

ABSTRACT

Flash Joule heating (FJH) is an emerging and profitable technology for converting inexhaustible biomass into flash graphene (FG). However, it is challenging to produce biomass FG continuously due to the lack of an integrated device. Furthermore, the high-carbon footprint induced by both excessive energy allocation for massive pyrolytic volatiles release and carbon black utilization in alternating current-FJH (AC-FJH) reaction exacerbates this challenge. Here, we create an integrated automatic system with energy requirement-oriented allocation to achieve continuous biomass FG production with a much lower carbon footprint. The programmable logic controller flexibly coordinated the FJH modular components to realize the turnover of biomass FG production. Furthermore, we propose pyrolysis-FJH nexus to achieve biomass FG production. Initially, we utilize pyrolysis to release biomass pyrolytic volatiles, and subsequently carry out the FJH reaction to focus on optimizing the FG structure. Importantly, biochar with appropriate resistance is self-sufficient to initiate the FJH reaction. Accordingly, the medium-temperature biochar-based FG production without carbon black utilization exhibited low carbon emission (1.9 g CO2-eq g-1 graphene), equivalent to a reduction of up to ~86.1% compared to biomass-based FG production. Undoubtedly, this integrated automatic system assisted by pyrolysis-FJH nexus can facilitate biomass FG into a broad spectrum of applications.


Subject(s)
Carbon , Charcoal , Graphite , Biomass , Soot
3.
J Mol Cell Biol ; 2024 Apr 05.
Article in English | MEDLINE | ID: mdl-38578631

ABSTRACT

The recognition of cytosolic nucleic acid triggers the DNA/RNA sensor-IRF3 axis-mediated production of type I interferons (IFNs), which are essential for antiviral immune responses. However, the inappropriate activation of these signaling pathways is implicated in autoimmune conditions. Here, we report that indomethacin, a widely used nonsteroidal anti-inflammatory drug, inhibits nucleic acid-triggered IFN production. We found that both DNA- and RNA-stimulated IFN expression can be effectively blocked by indomethacin. Interestingly, indomethacin also prohibits the nuclear translocation of IRF3 following cytosolic nucleic acid recognition. Importantly, in cell lines and a mouse model of Aicardi-Goutières syndrome, indomethacin administration blunts self-DNA-induced autoimmune responses. Thus, our study reveals a previously unknown function of indomethacin and provides a potential treatment for cytosolic nucleic acid-stimulated autoimmunity.

4.
Inorg Chem ; 63(9): 4078-4085, 2024 Mar 04.
Article in English | MEDLINE | ID: mdl-38390829

ABSTRACT

Providing efficient electronic transport channels has always been a promising strategy to mitigate the recombination of photogenerated charge carriers. In this study, a heterostructure composed of a semiconductor/photoinactive-metal-organic framework (MOF) was constructed to provide innovative channels for electronic transport. Prepared using a previously reported method ( Angew. Chem., Int. Ed. 2016, 55, 15301-15305) with slight modifications to temperature and reaction time, the CuS@HKUST-1 hollow cuboctahedron was synthesized. The CuS@HKUST-1 heterostructure possessed a well-defined cuboctahedral morphology with a uniform size of about 500 nm and a hollow structure with a thickness of around 50 nm. The CuS nanoparticles were uniformly distributed on the HKUST-1 shell. Structural characterization in cooperation with density functional theory (DFT) calculations revealed that CuS can effectively transfer photogenerated electrons to HKUST-1. CuS@HKUST-1 hollow cuboctahedrons were first introduced to the photocatalytic cycloaddition reaction of CO2 with epoxides, demonstrating excellent photocatalytic activity and stability at mild conditions (room temperature, solvent-free, and 1 atm CO2 pressure). The high photocatalytic performance of the CuS@HKUST-1 hollow cuboctahedron could be attributed to (1) the unique hollow cuboctahedron morphology, which provided a large specific surface area (693.1 m2/g) and facilitated the diffusion and transfer of reactants and products; and (2) CuS@HKUST-1 providing electronic transport channels from CuS to HKUST-1, which could enhance the adsorption and activation of CO2. Cu2+ carrying surplus electrons can activate CO2 to CO2-. The charge separation and transfer in the photocatalytic process can also be effectively promoted. This work provides a cost-effective and environmentally friendly approach for CO2 utilization reactions under ambient conditions, addressing the critical issue of rising atmospheric CO2 levels.

5.
Chem Sci ; 15(2): 692-700, 2024 Jan 03.
Article in English | MEDLINE | ID: mdl-38179522

ABSTRACT

The existence of the oxidation/reduction interface can promote the performance of a photocatalyst, due to its effect on the separation of photogenerated carriers and the surface reactivity. However, it is difficult to construct two sets of oxidation/reduction interfaces in a single crystal and compare their separation efficiency for photogenerated carriers. Introducing a high proportion of active facets into the co-exposed facets is even more challenging. Herein, a hollow anatase TiO2 tetrakaidecahedron (HTT) with two sets of oxidation/reduction interfaces ({001}/{101} and {001}/{110}) is synthesized by directional chemical etching. Theoretical and experimental results indicate that the {001}/{110} interface is a dominant oxidation/reduction interface, showing a better promotion on the separation of photogenerated carriers than the {001}/{101} interface. In the HTT, the ratio of dominant {001}/(110) is increased and the proportion of the active {110} facet is about 40% (generally about 15%). Therefore, the HTT shows excellent catalytic activity for photocatalytic reductive (hydrogen production) and oxidative (selective oxidation of sulfides) reactions. The HTT also demonstrates favorable photocatalytic activity for the cross-dehydrogenative coupling reaction, where both photogenerated electrons and photogenerated holes are involved, further verifying its high separation efficiency of photogenerated carriers and surface reactivity. This work provides an important guideline for developing advanced structures with a predetermined interface toward desired applications.

6.
Aesthetic Plast Surg ; 48(3): 333-340, 2024 Feb.
Article in English | MEDLINE | ID: mdl-37697086

ABSTRACT

BACKGROUND: Poor Bell's phenomenon is often considered a relative contraindication for ptosis surgery, as it increases the risk of corneal exposure and dry eye symptoms after surgery. However, the Bell's phenomenon may vary in different individuals and sleep stages, making it inaccurate to predict the position of the eye during sleep based on awake examination. This study aimed to investigate the role of Bell's phenomenon in ptosis surgery and the management of nocturnal lagophthalmos. METHODS: We conducted a retrospective case series of 23 patients with ptosis and poor Bell's phenomenon who underwent different surgical techniques at Xijing Hospital from April 2020 to June 2021. We assessed Bell's phenomenon at different stages of sleep and collected data on ptosis degree, surgical approach, lagophthalmos, complications, and outcomes. RESULTS: Of the total 23 patients originally considered for study, 9 with frontalis muscle advancement technique, 8 with conjoint fascial sheath suspension, 4 with levator resection technique, and 2 with levator aponeurosis plication technique. All patients achieved satisfactory correction of ptosis. One patient had prolonged lagophthalmos and underwent reoperation to lower the eyelid height. Other complications were minor and resolved with conservative treatment. CONCLUSION: We conclude that poor Bell's phenomenon is not a relative contraindication for ptosis surgery. Nocturnal lagophthalmos should be monitored after ptosis surgery regardless of the Bell's phenomenon results. Tape eyelid closure can be an effective solution to protect the corneal surface during nocturnal lagophthalmos. LEVEL OF EVIDENCE IV: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to Table of Contents or the online Instructions to Authors www.springer.com/00266 .


Subject(s)
Blepharoplasty , Blepharoptosis , Lagophthalmos , Humans , Retrospective Studies , Oculomotor Muscles/surgery , Blepharoptosis/surgery , Blepharoplasty/methods , Eyelids/surgery
7.
Ann Plast Surg ; 92(1): 12-16, 2024 Jan 01.
Article in English | MEDLINE | ID: mdl-38117043

ABSTRACT

BACKGROUND: Lagophthalmos, a common complication after blepharoptosis correction, has plagued oculoplastic surgeons. The goal of this study was to investigate the effect of tape eyelid closure on reducing the occurrence of lagophthalmos after blepharoptosis correction. METHODS: From April 2020 to June 2021, a total of 112 patients with severe congenital ptosis received corrective surgery at the Department of Plastic and Reconstructive Surgery, Xijing Hospital, Fourth Military Medical University. Of these, 48 underwent frontalis muscle advancement technique and 64 underwent conjoint fascial sheath suspension. Preoperative data collected included demographics, levator function, Bell's phenomenon, and marginal reflex distance 1 (MRD1). Postoperative data included surgery type, MRD1, eyelid closure function, aesthetic outcomes (including eyelid contour, eyelid symmetry, and eyelid crease), keratitis, and other complications. RESULTS: Frontalis muscle advancement technique group: the median of safe eye closure time was 7.3 months (positive Bell's phenomenon; interquartile range [IQR], 3.8-10.8 months) and 13.9 months (poor Bell's phenomenon; IQR, 11.6-16.1 months). There was a significant improvement between the preoperative and postoperative MRD1 (-1.52 ± 0.82 vs 3.85 ± 0.58 mm, P < 0.05). Conjoint fascial sheath suspension group: the median of safe eye closure time was 5.7 months (positive Bell's phenomenon; IQR, 2.9-8.5 months) and 12.4 months (poor Bell's phenomenon; IQR, 8.1-16.7 months). There was a significant improvement between the preoperative and postoperative MRD1 (-1.02 ± 0.91 vs 4.15 ± 1.03 mm, P < 0.05). All patients/guardians were satisfied with the aesthetic outcomes. CONCLUSIONS: Tape tarsorrhaphy is a safe, easy-to-learn method for treating lagophthalmos with a good aesthetic outcome.


Subject(s)
Blepharoplasty , Blepharoptosis , Lagophthalmos , Humans , Blepharoptosis/surgery , Blepharoptosis/congenital , Oculomotor Muscles/surgery , Eyelids/surgery , Blepharoplasty/methods , Retrospective Studies , Treatment Outcome
8.
Ann Plast Surg ; 92(1): 55-59, 2024 Jan 01.
Article in English | MEDLINE | ID: mdl-38117045

ABSTRACT

BACKGROUND: Severe congenital ptosis is a common ocular deformity in pediatric patients that can significantly impact visual development and aesthetic appearance, leading to negative psychosocial outcomes. The frontalis muscle advancement technique is a well-established surgical treatment for severe congenital ptosis. Aesthetic changes of the brow-eye continuum often plays an important role in ptosis surgery. METHODS: We conducted a single-center retrospective case series study of patients with severe congenital ptosis who underwent the frontalis muscle advancement technique at the Department of Plastic and Reconstructive Surgery, Xijing Hospital, Fourth Military Medical University between April 2020 and June 2021. The study aimed to evaluate the aesthetic changes of the eyebrow-eyelid continuum after surgery. The main outcome measurements included marginal reflex distance 1, palpebral fissure height, eyebrow position, upper eyelid to lower eyebrow distance, lower eyelid to upper eyebrow distance, and nasal base to lower eyelid distance. RESULTS: The study included 48 patients (66 eyelids), with 30 unilateral and 18 bilateral patients. Our analysis found that eyebrow height decreased by an average of 4.8% postoperatively relative to preoperatively in all patients. CONCLUSIONS: The frontalis muscle advancement technique has demonstrated effectiveness in achieving aesthetically pleasing outcomes in children with severe ptosis. It is crucial to pay careful attention to the brow-eye continuum during the correction process, as its harmony can greatly impact the final result.


Subject(s)
Blepharoplasty , Blepharoptosis , Humans , Child , Blepharoplasty/methods , Retrospective Studies , Blepharoptosis/surgery , Blepharoptosis/congenital , Esthetics , Muscles/surgery , Oculomotor Muscles/surgery
9.
Cell Res ; 33(11): 851-866, 2023 11.
Article in English | MEDLINE | ID: mdl-37580406

ABSTRACT

Ultra-stable fibrous structure is a hallmark of amyloids. In contrast to canonical disease-related amyloids, emerging research indicates that a significant number of cellular amyloids, termed 'functional amyloids', contribute to signal transduction as temporal signaling hubs in humans. However, it is unclear how these functional amyloids are effectively disassembled to terminate signal transduction. RHIM motif-containing amyloids, the largest functional amyloid family discovered thus far, play an important role in mediating necroptosis signal transduction in mammalian cells. Here, we identify heat shock protein family A member 8 (HSPA8) as a new type of enzyme - which we name as 'amyloidase' - that directly disassembles RHIM-amyloids to inhibit necroptosis signaling in cells and mice. Different from its role in chaperone-mediated autophagy where it selects substrates containing a KFERQ-like motif, HSPA8 specifically recognizes RHIM-containing proteins through a hydrophobic hexapeptide motif N(X1)φ(X3). The SBD domain of HSPA8 interacts with RHIM-containing proteins, preventing proximate RHIM monomers from stacking into functional fibrils; furthermore, with the NBD domain supplying energy via ATP hydrolysis, HSPA8 breaks down pre-formed RHIM-amyloids into non-functional monomers. Notably, HSPA8's amyloidase activity in disassembling functional RHIM-amyloids does not require its co-chaperone system. Using this amyloidase activity, HSPA8 reverses the initiator RHIM-amyloids (formed by RIP1, ZBP1, and TRIF) to prevent necroptosis initiation, and reverses RIP3-amyloid to prevent necroptosis execution, thus eliminating multi-level RHIM-amyloids to effectively prevent spontaneous necroptosis activation. The discovery that HSPA8 acts as an amyloidase dismantling functional amyloids provides a fundamental understanding of the reversibility nature of functional amyloids, a property distinguishing them from disease-related amyloids that are unbreakable in vivo.


Subject(s)
Amyloid , Necroptosis , Animals , Humans , Mice , HSC70 Heat-Shock Proteins/metabolism , Mammals , Protein Binding , Receptor-Interacting Protein Serine-Threonine Kinases/metabolism , Signal Transduction
10.
Nat Commun ; 14(1): 4975, 2023 Aug 17.
Article in English | MEDLINE | ID: mdl-37591830

ABSTRACT

Iron-based catalysts are promising candidates for advanced oxidation process-based wastewater remediation. However, the preparation of these materials often involves complex and energy intensive syntheses. Further, due to the inherent limitations of the preparation conditions, it is challenging to realise the full potential of the catalyst. Herein, we develop an iron-based nanomaterial catalyst via soft carbon assisted flash joule heating (FJH). FJH involves rapid temperature increase, electric shock, and cooling, the process simultaneously transforms a low-grade iron mineral (FeS) and soft carbon into an electron rich nano Fe0/FeS heterostructure embedded in thin-bedded graphene. The process is energy efficient and consumes 34 times less energy than conventional pyrolysis. Density functional theory calculations indicate that the electron delocalization of the FJH-derived heterostructure improves its binding ability with peroxydisulfate via bidentate binuclear model, thereby enhancing ·OH yield for organics mineralization. The Fe-based nanomaterial catalyst exhibits strong catalytic performance over a wide pH range. Similar catalysts can be prepared using other commonly available iron precursors. Finally, we also present a strategy for continuous and automated production of the iron-based nanomaterial catalysts.

11.
Genes Dis ; 10(6): 2597-2613, 2023 Nov.
Article in English | MEDLINE | ID: mdl-37554180

ABSTRACT

To uncover the role of satellite cells (SCs) in paravertebral muscle development and aging, we constructed a single-nucleus transcriptomic atlas of mouse paravertebral muscle across seven timepoints spanning the embryo (day 16.5) to old (month 24) stages. Eight cell types, including SCs, fast muscle cells, and slow muscle cells, were identified. An energy metabolism-related gene set, TCA CYCLE IN SENESCENCE, was enriched in SCs. Forty-two skeletal muscle disease-related genes were highly expressed in SCs and exhibited similar expression patterns. Among them, Pdha1 was the core gene in the TCA CYCLE IN SENESCENCE; Pgam2, Sod1, and Suclg1 are transcription factors closely associated with skeletal muscle energy metabolism. Transcription factor enrichment analysis of the 42 genes revealed that Myod1 and Mef2a were also highly expressed in SCs, which regulated Pdha1 expression and were associated with skeletal muscle development. These findings hint that energy metabolism may be pivotal in SCs development and aging. Three ligand-receptor pairs of extracellular matrix (ECM)-receptor interactions, Lamc1-Dag1, Lama2-Dag1, and Hspg2-Dag1, may play a vital role in SCs interactions with slow/fast muscle cells and SCs self-renewal. Finally, we built the first database of a skeletal muscle single-cell transcriptome, the Musculoskeletal Cell Atlas (http://www.mskca.tech), which lists 630,040 skeletal muscle cells and provides interactive visualization, a useful resource for revealing skeletal muscle cellular heterogeneity during development and aging. Our study could provide new targets and ideas for developing drugs to inhibit skeletal muscle aging and treat skeletal muscle diseases.

12.
Chem Commun (Camb) ; 59(52): 8131-8134, 2023 Jun 27.
Article in English | MEDLINE | ID: mdl-37307013

ABSTRACT

In this paper, a series of micro-nano reactors assembled by N doped carbon coated TiO2 heterojunction nanosheets with different thickness, named TiO2/N-C hollow framework (HF), TiO2/N-C hollow hexahedron assembled by nanosheets (HHS), and TiO2/N-C hollow hexahedron assembled by ultrathin nanosheets (HHUS), have been prepared by adjusting the alcoholysis rate of NH2-MIL-125 and then pyrolysis. Experimental and theoretical studies revealed that with the decrease of the thickness of the heterojunction nanosheet subunit, more low-coordination Ti atoms would be exposed as effective sites for photocatalytic H2 evolution, and the interaction between the carbon layer and TiO2 would also be enhanced, which provided a smooth migration path for the effective separation of photogenerated carriers. Thus, TiO2/N-C HHUS with the thinnest nanosheet subunit exhibited the best photoelectric performance and the highest photocatalytic hydrogen production activity.

13.
Aesthetic Plast Surg ; 47(4): 1430-1438, 2023 08.
Article in English | MEDLINE | ID: mdl-37193888

ABSTRACT

BACKGROUND: For moderate ptosis associated with fair levator function (LF), the levator resection is the most commonly used procedure. However, the levator resection technique still has some disadvantages, such as residual lagophthalmos (RL), undercorrection, conjunctival prolapse, and eyelid contour abnormality. To solve the above problems, our team have made modifications to the levator resection technique in three aspects: releasing the levator muscle sufficiently, preserving the supporting structure of the conjunctiva, and placing multiple suture sites. METHODS: Fifty-seven patients (81 eyes) underwent the modified levator resection technique and were enrolled in the study. Preoperative data collected included age, sex, margin reflex distance 1 (MRD1), and LF. Postoperative data collected included MRD1, RL, patient satisfaction, complications, and length of follow-up. RESULTS: Mean MRD1 significantly increased from 1.45 ± 0.65 mm preoperatively to 3.57 ± 0.51 mm postoperatively. Mean LF significantly increased from 6.49 ± 1.12 mm preoperatively to 9.48 ± 1.39 mm postoperatively. Successful correction was obtained in 77 eyes (95.1%). Mean RL was 1.09 ± 0.57 and 72 eyes (88.9%) showed excellent or good eyelid closure function. Fifty-four patients (94.7%) were completely satisfied with the final result. Complications such as hematoma, infection, conjunctival prolapse, suture exposure, corneal abrasion, and keratitis were not found in any cases during follow-up. CONCLUSION: This modified levator resection technique introduced in this study is effective in correcting moderate congenital blepharoptosis, while minimizing RL, undercorrection, conjunctival prolapse, eyelid contour abnormality by releasing the levator muscle sufficiently, preserving the supporting structure of the conjunctiva, and placing multiple suture sites. LEVEL OF EVIDENCE IV: This journal requires that authors 42 assign a level of evidence to each article. For a full 43 description of these Evidence-Based Medicine ratings, 44 please refer to the Table of Contents or the online 45 Instructions to Authors www.springer.com/00266 .


Subject(s)
Blepharoplasty , Blepharoptosis , Lagophthalmos , Humans , Blepharoptosis/surgery , Blepharoptosis/congenital , Eyelids/abnormalities , Retrospective Studies , Blepharoplasty/methods , Oculomotor Muscles/surgery , Prolapse , Treatment Outcome
15.
Nat Rev Mol Cell Biol ; 24(2): 85, 2023 02.
Article in English | MEDLINE | ID: mdl-36266548
16.
Sensors (Basel) ; 22(23)2022 Nov 22.
Article in English | MEDLINE | ID: mdl-36501734

ABSTRACT

Indoor localization problems are difficult due to that the information, such as WLAN and GPS, cannot achieve enough precision for indoor issues. This paper presents a novel indoor localization algorithm, GeoLoc, with uncertainty eliminate based on fusion of acceleration, angular rate, and magnetic field sensor data. The algorithm can be deployed in edge devices to overcome the problems of insufficient computing resources and long delay caused by high complexity of location calculation. Firstly, the magnetic map is built and magnetic values are matched. Secondly, orientation updating and position selection are iteratively executed using the fusion data, which gradually reduce uncertainty of orientation. Then, we filter the trajectory from a path set. By gradually reducing uncertainty, GeoLoc can bring a high positioning precision and a smooth trajectory. In addition, this method has an advantage in that it does not rely on any infrastructure such as base stations and beacons. It solves the common problems regarding the non-uniqueness of the geomagnetic fingerprint and the deviation of the sensor measurement. The experimental results show that our algorithm achieves an accuracy of less than 2.5 m in indoor environment, and the positioning results are relatively stable. It meets the basic requirements of indoor location-based services (LBSs).

17.
Foods ; 11(24)2022 Dec 19.
Article in English | MEDLINE | ID: mdl-36553840

ABSTRACT

This research aimed to establish an effective storage method to maintain the quality of processed sea cucumbers. In this study, sea cucumbers were stored by various methods including the storage of live sea cucumbers (seawater treatment, oxygen treatment, and ascorbic acid treatment) and the storage of dead sea cucumbers (frozen treatment). The sea cucumber quality was monitored after storage and boiling. The weightlessness rate and WHC of the frozen group increased to 86.96% ± 0.83% and 93.29% ± 0.32%, respectively. Frozen sea cucumbers shrunk with the meat's textural properties deteriorated. During the live sea cucumber storage, the tissue protein degraded from day 3 to day 7 which led to the promotion of TVB-N. Among these, the oxygen group showed the smallest TVB-N increase from day 0 (3.78 ± 0.60 mg 100 g-1) to day 7 (10.40 ± 0.12 mg 100 g-1). The oxygen group exhibited the most moderate change in weightlessness rate (4.24% ± 0.45%) and the most moderate texture parameters decline, such as the hardness of 32.52%, chewiness of 78.98 ± 5.10 N, and adhesion of 0.84 ± 0.00. The oxygen method showed the best condition of sea cucumber after 5 days of storage.

18.
Dalton Trans ; 51(42): 16361-16370, 2022 Nov 01.
Article in English | MEDLINE | ID: mdl-36250296

ABSTRACT

Semi-hydrogenation of alkynes to prepare alkenes is an important reaction in the petrochemical and fine chemical industries. The use of conventional Pd nanoparticle-based catalysts is limited by alkyne over-hydrogenation and low Pd utilization. In this study, a nitrogen-doped mesoporous carbon material (m-NC), which was rich in defect sites after Zn volatilization, was fabricated by the carbonization of ZIF-8. Ultrafine PdCo bimetallic nanoclusters with Co atom-modified Pd active site electronic and compositional structure were highly dispersed and confined in m-NC. As-obtained Pd0.43Co1/m-NC was used for the semi-hydrogenation of alkynes and it exhibited high selectivity with high conversion under mild reaction conditions. Pd0.43Co1/m-NC also exhibited excellent stability in leaching tests and maintained its catalytic activity for at least nine reaction cycles. The highly dispersed active sites in Pd0.43Co1/m-NC served as the active sites for the catalytic semi-hydrogenation of alkynes; as a regulator, the second metal Co effectively improved selectivity, and m-NC endowed the catalyst with excellent stability. The research work presented here may provide a foundation for the design of highly active, selective, and stable Pd-based bimetallic catalysts for selective hydrogenation.

19.
Int J Biol Macromol ; 221: 1512-1526, 2022 Nov 30.
Article in English | MEDLINE | ID: mdl-35998852

ABSTRACT

Polylactide (PLA) is one of the most attractive bioplastics as it can be produced from nontoxic renewable feedstock. However, its inherently poor toughness greatly limits its large-scale application. Cost-effectively toughening PLA without sacrificing its transparency remains a big challenge. We herein prepared an imidazolium-based poly(ionic liquid)-b-PLA copolymer (ILA) and ionomers as toughening agent for PLA through an integrative approach including continuous-monomer-feeding copolymerization, quaternization reaction, ion exchange and inter-ionomers blending. By blending PLA with the ILA and ionomers, we successfully obtained PLA materials with combined features including high toughness, good transparency and antibacterial properties. The effects of regulated ionomer composition and ILA compatibilizer on phase morphology, mechanical properties and transparency of the blends were systematically studied. The optimum formulation (PLA/E12/ILA 60/40/5) shows an impressive transmittance of 89-93 %, high impact strength of 45 kJ/m2 and elongation at break at 170 %, which are about 17 and 24 times that of pure PLA, respectively. More interestingly, the presence of imidazolium cation and anion groups endows the blends with attractive antibacterial properties. Ion exchange between ILA copolymer and the imidazolium-containing ionomeric system leads to a synergistic effect of compatibilization and efficient toughening, providing a new strategy for develop high performance PLA materials.


Subject(s)
Ionic Liquids , Biocompatible Materials , Polyesters , Anti-Bacterial Agents/pharmacology
20.
Front Chem ; 10: 923174, 2022.
Article in English | MEDLINE | ID: mdl-35783218

ABSTRACT

A series of ultra-toughened sustainable blends were prepared from poly(lactic acid) (PLA) and bromobutyl rubber-based ionomers (i-BIIRs) via reactive blending, in which dicumyl peroxide (DCP) and Joncryl®ADR-4440 (ADR) were used as reactive blending additives. The miscibility, phase morphology and mechanical property of the PLA/i-BIIRs blends were thoroughly investigated through DMA, SEM, tensile and impact tests. The influence of different ionic groups and the effects of DCP and ADR on the compatibility between the phases, phase structure and mechanical properties were analyzed. The introduction of the imidazolium-based ionic groups and the reactive agents enable the i-BIIRs play multiple roles as effective compatibilizers and toughening agents, leading to improved interfacial compatibility and high toughness of the blends. The mechanical properties test showed that the PLA/i-BIIRs blends exhibit excellent toughness: impact strength and the elongation at break of AR-OH(30)+AD reached 95 kJ/m2 and 286%, respectively. The impact fracture surface showed the large-scale plastic deformation of the PLA matrix in the blends, resulting in greatly absorbing the impact energy. The results proved that simultaneously applying reactive blend and multiple intermolecular interactions methods is an effective toughening strategy for toughening modification of the PLA blends.

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