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1.
Nat Commun ; 15(1): 6098, 2024 Jul 19.
Artículo en Inglés | MEDLINE | ID: mdl-39030230

RESUMEN

The electrochemical oxygen reduction reaction (ORR) to produce hydrogen peroxide (H2O2) is appealing due to its sustainability. However, its efficiency is compromised by the competing 4e- ORR pathway. In this work, we report a hierarchical carbon nanosheet array electrode with a single-atom Ni catalyst synthesized using organic molecule-intercalated layered double hydroxides as precursors. The electrode exhibits excellent 2e- ORR performance under alkaline conditions and achieves H2O2 yield rates of 0.73 mol gcat-1 h-1 in the H-cell and 5.48 mol gcat-1 h-1 in the flow cell, outperforming most reported catalysts. The experimental results show that the Ni atoms selectively adsorb O2, while carbon nanosheets generate reactive hydrogen species, synergistically enhancing H2O2 production. Furthermore, a coupling reaction system integrating the 2e- ORR with ethylene glycol oxidation significantly enhances H2O2 yield rate to 7.30 mol gcat-1 h-1 while producing valuable glycolic acid. Moreover, we convert alkaline electrolyte containing H2O2 directly into the downstream product sodium perborate to reduce the separation cost further. Techno-economic analysis validates the economic viability of this system.

2.
Angew Chem Int Ed Engl ; : e202412637, 2024 Jul 23.
Artículo en Inglés | MEDLINE | ID: mdl-39044283

RESUMEN

The dynamic structure evolution of heterogeneous catalysts during reaction has gained great attention recently. However, controllably manipulating dynamic process and then feeding back catalyst design to extend the lifetime remains challenging. Herein, we proposed an entropy variation strategy to develop a dynamic CuZn-Co/HEOs catalyst, in which the non-active Co nano-islands play a crucial role in controlling thermal effect via timely capturing and utilizing reaction heat generated on the adjacent active CuZn alloys, thus solving the deactivation problem of Cu-based catalysts. Specifically, heat sensitive Co nano-islands experienced an entropy increasing process of slowly redispersion during the reaction. Under such heat dissipation effect, the CuZn-Co/HEOs catalyst exhibited 95.7% ethylene selectivity and amazing long-term stability (>530 h) in the typical exothermic acetylene hydrogenation. Aiming at cultivating it as a catalyst with promising industrial potential, we proposed a simple regeneration approach via an entropy decreasing process.

3.
Clin Transl Radiat Oncol ; 46: 100767, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38576855

RESUMEN

Centrally located hepatocellular carcinoma (HCC) is difficult to be radically resected due to its special location close to major hepatic vessels. Thus, we aimed to assess whether stereotactic body radiation therapy (SBRT) can be an effective and safe approach for centrally located HCC. This retrospective study included 172 patients with centrally located HCC who were treated with SBRT. Overall survival (OS) was analyzed as the primary endpoint. Rates of progression-free survival (PFS), local control, intrahepatic relapse, extrahepatic metastasis and toxicities were analyzed as secondary endpoints. The OS rates of 1-, 3-, and 5-year were 97.7%, 86.7%, and 76.3%, respectively. The PFS/local control rates of 1-, 3-, and 5-year were 94.1%/98.2%, 76.8%/94.9%, and 59.3%/92.3%, respectively. The cumulative incidence of intrahepatic relapse/extrahepatic metastases of 1-, 3-, and 5-year were 3.7%/2.9%, 25.0%/7.4%, and 33.3%/9.8%, respectively. Both univariate and multivariate analyses revealed that patients received BED10 at 100 Gy or more had better OS. Radiation-related adverse events were mild to moderate according to Common Terminology Criteria for Adverse Events, and no toxicities over grade 3 were observed. Patients with centrally located HCC in our cohort who received SBRT had similar OS and PFS rates compared to those reported in literatures who received surgery with neoadjuvant or adjuvant intensity-modulated radiation therapy. These results indicate that SBRT is an effective and well-tolerated method for patients with centrally located HCC, suggesting that it may serve as a reasonable alternative treatment for these kind of patients.

4.
J Am Chem Soc ; 146(1): 1071-1080, 2024 Jan 10.
Artículo en Inglés | MEDLINE | ID: mdl-38157430

RESUMEN

Strong metal-support interaction (SMSI) has been extensively studied in heterogeneous catalysis because of its significance in stabilizing active metals and tuning catalytic performance, but the origin of SMSI is not fully revealed. Herein, by using Pt/CeO2 as a model catalyst, we report an embedding structure at the interface between Pt and (110) plane of CeO2, where Pt clusters (∼1.6 nm) are embedded into the lattice of ceria within 3-4 atomic layers. In contrast, this phenomenon is absent in the CeO2(100) support. This unique geometric structure, as an effective motivator, triggers more significant electron transfer from Pt clusters to CeO2(110) support accompanied by the formation of interfacial structure (Ptδ+-Ov-Ce3+), which plays a crucial role in stabilizing Pt nanoclusters. A comprehensive investigation based on experimental studies and theoretical calculations substantiates that the interfacial sites serve as the intrinsic active center toward water-gas shift reaction (WGSR), featuring a moderate strength CO activation adsorption and largely decreased energy barrier of H2O dissociation, accounting for the prominent catalytic activity of Pt/CeO2(110) (a reaction rate of 15.76 molCO gPt-1 h-1 and a turnover frequency value of 2.19 s-1 at 250 °C). In addition, the Pt/CeO2(110) catalyst shows a prominent durability within a 120 h time-on-stream test, far outperforming the Pt/CeO2(100) one, which demonstrates the advantages of this embedding structure for improving catalyst stability.

5.
Int J Syst Evol Microbiol ; 73(12)2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38059799

RESUMEN

A bacterium, designated strain ZK17L-C2T, was isolated from the leaf tissues of wheat (Triticum aestivum) collected in Chengdu, Sichuan Province, PR China. It is aerobic, non-motile, Gram-negative, rod-shaped and red-to-pink in colour. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain ZK17L-C2T belonged to the genus Hymenobacter and was most closely related to Hymenobacter rigui KCTC 12533T (98.68 %) and Hymenobacter metallilatus 9PBR-2T (98.19 %). Digital DNA-DNA hybridization (dDDH) values between strain ZK17L-C2T and these two type strains were 26.6 and 26.5 %, and average nucleotide identity (ANI) values were 84.9 and 84.8 %, respectively; these values are lower than the proposed and generally accepted species boundaries for dDDH and ANI. The genomic DNA G+C content of strain ZK17L-C2T was 59.4 mol%. It can grow at pH 5.5-7.5 and 15-30 °C, which is different from the closely related type strains. The major fatty acids of strain ZK17L-C2T were iso-C15 : 0, C16 : 0 and C18 : 0. Overall, the results from biochemical, chemical taxonomy and phylogenetic analyses indicate that strain ZK17L-C2T (=CGMCC 1.19373T=KCTC 92184 T) represents a new species of the genus Hymenobacter, for which the name Hymenobacter endophyticus sp. nov. is proposed.


Asunto(s)
Cytophagaceae , Ácidos Grasos , Ácidos Grasos/química , Triticum , Filogenia , ARN Ribosómico 16S/genética , ADN Bacteriano/genética , Composición de Base , Técnicas de Tipificación Bacteriana , Análisis de Secuencia de ADN , Hojas de la Planta
6.
Sheng Li Xue Bao ; 75(4): 555-568, 2023 Aug 25.
Artículo en Chino | MEDLINE | ID: mdl-37583043

RESUMEN

The development of chronic liver disease can be promoted by excessive fat accumulation, dysbiosis, viral infections and persistent inflammatory responses, which can lead to liver inflammation, fibrosis and carcinogenesis. An in-depth understanding of the etiology leading to chronic liver disease and the underlying mechanisms influencing its development can help identify potential therapeutic targets for targeted treatment. Orphan nuclear receptors (ONRs) are receptors that have no corresponding endogenous ligands to bind to them. The study of these ONRs and their biological properties has facilitated the development of synthetic ligands, which are important for investigating the effective targets for the treatment of a wide range of diseases. In recent years, it has been found that ONRs are essential for maintaining normal liver function and their dysfunction can affect a variety of liver diseases. ONRs can influence pathophysiological activities such as liver lipid metabolism, inflammatory response and cancer cell proliferation by regulating hormones/transcription factors and affecting the biological clock, oxidative stress, etc. This review focuses on the regulation of ONRs, mainly including retinoid related orphan nuclear receptors (RORs), pregnane X receptor (PXR), leukocyte cell derived chemotaxin 2 (LECT2), Nur77, and hepatocyte nuclear factor 4α (HNF4α), on the development of different types of chronic liver diseases in different ways, in order to provide useful references for the therapeutic strategies of chronic liver diseases based on the regulation of ONRs.


Asunto(s)
Hepatopatías , Receptores de Esteroides , Humanos , Receptores Nucleares Huérfanos/metabolismo , Receptores de Esteroides/fisiología , Ligandos , Hígado , Péptidos y Proteínas de Señalización Intercelular
7.
Dalton Trans ; 52(28): 9757-9771, 2023 Jul 18.
Artículo en Inglés | MEDLINE | ID: mdl-37395360

RESUMEN

Antibiotic abuse has caused the generation of drug-resistant bacteria and a series of infections induced by multidrug-resistant bacteria have become a threat to human health. Facing the failure of traditional antibiotics, antibacterial drugs with new molecular and action modes urgently need to be developed. In this study, ruthenium complexes containing coumarin were designed and synthesized. By altering the structure of the ancillary ligand, we explored the biological activities of four ruthenium complexes against Staphylococcus aureus. Among them, Ru(II)-1 with the best antibacterial activity (minimum inhibitory concentration: 1.56 µg mL-1) was used for further investigations. Surprisingly, Ru(II)-1 could significantly inhibit the formation of biofilm and hinder the development of drug-resistant bacteria. Besides, Ru(II)-1 also exhibited excellent biocompatibility. Antibacterial mechanism studies suggested that Ru(II)-1 could target the bacterial cell membrane and combine with the phospholipid component of the membrane (phosphatidylglycerol and phosphatidylethanolamine) and generate reactive oxygen species to induce an oxidative stress response, which resulted in the damage of membrane integrity, finally leading bacteria death. Moreover, antibacterial tests in G. mellonella larvae and mice in vivo model indicated that Ru(II)-1 had the potential to combat S. aureus infection. Therefore, all the above results showed that ruthenium complexes modified with coumarin could be a promising antibacterial agent to tackle bacterial infection problems.


Asunto(s)
Complejos de Coordinación , Infecciones por Bacterias Grampositivas , Rutenio , Animales , Humanos , Ratones , Staphylococcus aureus , Rutenio/farmacología , Rutenio/química , Complejos de Coordinación/farmacología , Complejos de Coordinación/química , Antibacterianos/farmacología , Antibacterianos/química , Bacterias , Pruebas de Sensibilidad Microbiana , Cumarinas/farmacología
8.
Angew Chem Int Ed Engl ; 62(37): e202307573, 2023 Sep 11.
Artículo en Inglés | MEDLINE | ID: mdl-37489697

RESUMEN

Understanding the radical behaviours during polymer degradation is beneficial to unveil and regulate the degradation pathways of polymers to achieve a sustainable polymer development. However, it is a long-standing challenge to study radical behaviours owing to the ultra-short lifetime of the transient radicals generated during the polymer degradation. In this contribution, we have proposed the radical-triggered luminescence to monitor the radical behaviours during polymer degradation without/with the addition of inorganic additives. It was disclosed that the pure polymers showed a single sigmoidal dynamic curve from peroxy radicals (ROO⋅) emissions, leading to the exponential proliferation for the degradation evolution. Alternatively, the degradation pathways with the addition of additives, layered double hydroxides (LDHs) with positively charged Al centers, could be modulated into a double sigmoidal dynamics, involving the main product of alkoxy radicals (RO⋅) with the activation energy of 40.2 kJ/mol and a small amount of ROO⋅ with 76.3 kJ/mol, respectively. Accordingly, the polymers with the additive-regulated pathways could exhibit prominently anti-degradation behaviours. This work is beneficial for the deep understanding of the radical mechanisms during polymer degradation, and for the rational design of anti-degradation polymers.

9.
Eur Heart J ; 44(29): 2713-2726, 2023 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-37377039

RESUMEN

AIMS: The variant p.Arg149Cys in ACTA2, which encodes smooth muscle cell (SMC)-specific α-actin, predisposes to thoracic aortic disease and early onset coronary artery disease in individuals without cardiovascular risk factors. This study investigated how this variant drives increased atherosclerosis. METHODS AND RESULTS: Apoe-/- mice with and without the variant were fed a high-fat diet for 12 weeks, followed by evaluation of atherosclerotic plaque formation and single-cell transcriptomics analysis. SMCs explanted from Acta2R149C/+ and wildtype (WT) ascending aortas were used to investigate atherosclerosis-associated SMC phenotypic modulation. Hyperlipidemic Acta2R149C/+Apoe-/- mice have a 2.5-fold increase in atherosclerotic plaque burden compared to Apoe-/- mice with no differences in serum lipid levels. At the cellular level, misfolding of the R149C α-actin activates heat shock factor 1, which increases endogenous cholesterol biosynthesis and intracellular cholesterol levels through increased HMG-CoA reductase (HMG-CoAR) expression and activity. The increased cellular cholesterol in Acta2R149C/+ SMCs induces endoplasmic reticulum stress and activates PERK-ATF4-KLF4 signaling to drive atherosclerosis-associated phenotypic modulation in the absence of exogenous cholesterol, while WT cells require higher levels of exogenous cholesterol to drive phenotypic modulation. Treatment with the HMG-CoAR inhibitor pravastatin successfully reverses the increased atherosclerotic plaque burden in Acta2R149C/+Apoe-/- mice. CONCLUSION: These data establish a novel mechanism by which a pathogenic missense variant in a smooth muscle-specific contractile protein predisposes to atherosclerosis in individuals without hypercholesterolemia or other risk factors. The results emphasize the role of increased intracellular cholesterol levels in driving SMC phenotypic modulation and atherosclerotic plaque burden.


Asunto(s)
Aterosclerosis , Hiperlipidemias , Placa Aterosclerótica , Ratones , Animales , Placa Aterosclerótica/complicaciones , Actinas/metabolismo , Ratones Noqueados para ApoE , Aterosclerosis/etiología , Colesterol/metabolismo , Hiperlipidemias/complicaciones , Miocitos del Músculo Liso/metabolismo , Miocitos del Músculo Liso/patología , Músculo Liso/metabolismo , Músculo Liso/patología , Apolipoproteínas E/genética , Apolipoproteínas E/metabolismo , Ratones Endogámicos C57BL , Ratones Noqueados
10.
Nat Commun ; 14(1): 3189, 2023 Jun 02.
Artículo en Inglés | MEDLINE | ID: mdl-37268617

RESUMEN

The metal-support interaction (MSI) in heterogeneous catalysts plays a crucial role in reforming reaction to produce renewable hydrogen, but conventional objects are limited to single metal and support. Herein, we report a type of RhNi/TiO2 catalysts with tunable RhNi-TiO2 strong bimetal-support interaction (SBMSI) derived from structure topological transformation of RhNiTi-layered double hydroxides (RhNiTi-LDHs) precursors. The resulting 0.5RhNi/TiO2 catalyst (with 0.5 wt.% Rh) exhibits extraordinary catalytic performance toward ethanol steam reforming (ESR) reaction with a H2 yield of 61.7%, a H2 production rate of 12.2 L h-1 gcat-1 and a high operational stability (300 h), which is preponderant to the state-of-the-art catalysts. By virtue of synergistic catalysis of multifunctional interface structure (Rh-Niδ--Ov-Ti3+; Ov denotes oxygen vacancy), the generation of formate intermediate (the rate-determining step in ESR reaction) from steam reforming of CO and CHx is significantly promoted on 0.5RhNi/TiO2 catalyst, accounting for its ultra-high H2 production.

11.
Dalton Trans ; 52(25): 8737-8746, 2023 Jun 27.
Artículo en Inglés | MEDLINE | ID: mdl-37313713

RESUMEN

Bacterial infection is one of the most serious public health problems, being harmful to human health and expensive. Nowadays, the misuse and overuse of antibiotics have led to the emergence of drug resistance. Therefore, it is an urgent need to develop new antimicrobial agents to address the current situation. In this study, four 1,2,4-triazole ruthenium polypyridine complexes [Ru(bpy)2(TPIP)](PF6)2 (Ru1), [Ru(dmb)2(TPIP)](PF6)2 (Ru2), [Ru(dtb)2(TPIP)](PF6)2 (Ru3) and [Ru(dmob)2(TPIP)](PF6)2 (Ru4) (bpy = 2,2'-bipyridine, dmb = 4,4'-dimethyl-2,2'-bipyridine, dtb = 4,4'-di-tert-butyl-2,2'-bipyridine, dmob = 4,4'-dimethoxy-2,2'-bipyridine and TPIP = 2-(4-(1H-1,2,4-triazol-1-yl)phenyl)-1H-imidazo[4,5-f][1,10]phenanthroline) were synthesized and evaluated for antibacterial activity. Results showed that the minimum inhibitory concentration (MIC) value of Ru3 against Staphylococcus aureus (S. aureus) was only 0.78 µg mL-1, showing the best antimicrobial activity in vitro. Besides, Ru3 showed low hemolytic activity and good biocompatibility. Due to its ability to damage the cell membrane of Staphylococcus bacteria, Ru3 was able to kill bacteria in a short time. Importantly, by inhibiting bacterial toxins and the formation of biofilm, Ru3 was not susceptible to the development of drug resistance. Moreover, Ru3 revealed excellent therapeutic effects in vivo and showed no irritation to the skin of mice. In conclusion, the four obtained 1,2,4-triazole ruthenium polypyridine complexes show strong antibacterial activity and satisfactory biocompatibility with excellent potential for antibacterial treatment, and provide a new solution for the current antibacterial crisis.


Asunto(s)
Antineoplásicos , Complejos de Coordinación , Rutenio , Ratones , Animales , Humanos , Staphylococcus aureus , Rutenio/farmacología , Antibacterianos/farmacología , 2,2'-Dipiridil/farmacología , Complejos de Coordinación/farmacología , Antineoplásicos/farmacología
12.
World J Biol Chem ; 14(3): 62-71, 2023 May 27.
Artículo en Inglés | MEDLINE | ID: mdl-37273684

RESUMEN

BACKGROUND: Erythrocyte alloantibodies are mainly produced after immune stimulation, such as blood transfusion, pregnancy, and transplantation, and are the leading causes of severe hemolytic transfusion reactions and difficulty in blood grouping and matching. Therefore, antibody screening is critical to prevent and improve red cell alloantibodies. Routine tube assay is the primary detection method of antibody screening. Recently, erythrocyte-magnetized technology (EMT) has been increasingly used in clinical practice. This study intends to probe the application and efficacy of the conventional tube and EMT in red blood cell alloantibody titration to provide a reference for clinical blood transfusion. AIM: To investigate the application value of conventional tube and EMT in red blood cell alloantibody titration and enhance the safety of blood transfusion practice. METHODS: A total of 1298 blood samples were harvested from blood donors at the Department of Blood Transfusion of our hospital from March 2021 to December 2022. A 5 mL blood sample was collected in tubing, which was then cut, and the whole blood was put into a test tube for centrifugation to separate the serum. Different red blood cell blood group antibody titers were simultaneously detected using the tube polybrene test, tube antiglobulin test (AGT), and EMT screening irregular antibody methods to determine the best test method. RESULTS: Simultaneous detection was performed through the tube polybrene test, tube AGT and EMT screening irregular antibodies. It was discovered that the EMT screening irregular antibody method could detect all immunoglobulin G (IgG) and immunoglobulin M (IgM) irregular antibodies, and the results of manual tube AGT were satisfactory, but the operation time was lengthy, and the equipment had a large footprint. The EMT screening irregular antibody assay was also conducted to determine its activity against type O Rh (D) red blood cells, and the outcomes were satisfactory. Furthermore, compared to the conventional tube method, the EMT screening irregular antibody method was more cost-effective and had significantly higher detection efficiency. CONCLUSION: With a higher detection rate, the EMT screening irregular antibody method can detect both IgG and IgM irregular antibodies faster and more effectively than the conventional tube method.

13.
Res Sq ; 2023 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-36909460

RESUMEN

Missense variants throughout ACTA2, encoding smooth muscle α-actin (αSMA), predispose to adult onset thoracic aortic disease, but variants disrupting arginine 179 (R179) lead to Smooth Muscle Dysfunction Syndrome (SMDS) characterized by childhood-onset diverse vascular diseases. Our data indicate that αSMA localizes to the nucleus in wildtype (WT) smooth muscle cells (SMCs), enriches in the nucleus with SMC differentiation, and associates with chromatin remodeling complexes and SMC contractile gene promotors, and the ACTA2 p.R179 variant decreases nuclear localization of αSMA. SMCs explanted from a SMC-specific conditional knockin mouse model, Acta2SMC-R179/+, are less differentiated than WT SMCs, both in vitro and in vivo, and have global changes in chromatin accessibility. Induced pluripotent stem cells from patients with ACTA2 p.R179 variants fail to fully differentiate from neural crest cells to SMCs, and single cell transcriptomic analyses of an ACTA2 p.R179H patient's aortic tissue shows increased SMC plasticity. Thus, nuclear αSMA participates in SMC differentiation and loss of this nuclear activity occurs with ACTA2 p.R179 pathogenic variants.

14.
Mar Pollut Bull ; 190: 114863, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-36989599

RESUMEN

Developing effective marine water quality criteria (WQC) is crucial for controlling marine contamination and protecting marine life. The WQC for copper is urgently needed due to the toxicity and widespread of copper contamination. In this work, both short-term water quality criteria (SWQC) and long-term water quality criteria (LWQC) under 10 % effect endpoints were derived by using the model averaging of species sensitivity distribution (SSD10) method for Bohai Bay. The WQC values were obtained directly from the hazardous concentration for 5 % of species (HC5) values, which removes the influence of arbitrary assessment factor (AF). Modifications to the acute-chronic ratio (ACR) strategies and the inclusion of the test toxicity data of local species also improved the accuracy and applicability of the WQC values. The derived SWQC and LWQC were 2.21 and 0.45 µg/L, respectively. Furthermore, the overall risk level of copper in Bohai Bay was evaluated by using the risk quotient (RQ) method, and the results showed it was at a moderate-low level. This study provides a new approach for the derivation of the WQC for Cu and the risk assessment of Bohai Bay, which is essential for the protection of local aquatic life and provides guidance to the establishment of the national WQC.


Asunto(s)
Contaminantes Químicos del Agua , Calidad del Agua , Cobre/análisis , Organismos Acuáticos , Bahías , Contaminantes Químicos del Agua/análisis , Medición de Riesgo/métodos , China
15.
Mikrochim Acta ; 190(3): 98, 2023 02 20.
Artículo en Inglés | MEDLINE | ID: mdl-36806988

RESUMEN

Graphdiyne (GDY) has attracted a lot of interest in electrochemical sensing application with the advantages of a large conjugation system, porous structure, and high structure defects. Herein, to further improve the sensing effect of GDY, conductive MWCNTs were chosen as the signal accelerator. To get a stable composite material, polydopamine (PDA) was employed as connecting bridge between GDY and MWCNTs-NH2, where DA was firstly polymerized onto GDY, followed by covalently linking MWCNTs-NH2 with PDA through Michael-type reaction. The formed GDY@PDA/MWCNTs-NH2 composite was then explored as an electrochemical sensor for benomyl (Ben) determination. GDY assists the adsorption and accumulation of Ben molecules to the sensing surface, while MWCNTs-NH2 can enhance the electrical conductivity and electrocatalytic activity, all of which contributing to the significantly improved performance. The proposed sensor displays an obvious oxidation peak at 0.72 V (vs. Hg|Hg2Cl2) and reveals a wide linear range from 0.007 to 10.0 µM and a low limit of detection (LOD) of 1.8 nM (S/N = 3) toward Ben detection. In addition, the sensor shows high stability, repeatability, reproducibility, and selectivity. The feasibility of this sensor was demonstrated by detecting Ben in apple and cucumber samples with a recovery of 94-106% and relative standard deviations (RSDs) less than 2.3% (n = 5). A sensitive electrochemical sensing platform was reported for benomyl (Ben) determination based on a highly stable GDY@PDA/MWCNTs-NH2 composite.


Asunto(s)
Nanotubos de Carbono , Nanotubos de Carbono/química , Técnicas Electroquímicas , Benomilo , Reproducibilidad de los Resultados
16.
Chem Rev ; 123(6): 3007-3088, 2023 Mar 22.
Artículo en Inglés | MEDLINE | ID: mdl-36802560

RESUMEN

Polymers have been widely applied in various fields in the daily routines and the manufacturing. Despite the awareness of the aggressive and inevitable aging for the polymers, it still remains a challenge to choose an appropriate characterization strategy for evaluating the aging behaviors. The difficulties lie in the fact that the polymer features from the different aging stages require different characterization methods. In this review, we present an overview of the characterization strategies preferable for the initial, accelerated, and late stages during polymer aging. The optimum strategies have been discussed to characterize the generation of radicals, variation of functional groups, substantial chain scission, formation of low-molecular products, and deterioration in the polymers' macro-performances. In view of the advantages and the limitations of these characterization techniques, their utilization in a strategic approach is considered. In addition, we highlight the structure-property relationship for the aged polymers and provide available guidance for lifetime prediction. This review could allow the readers to be knowledgeable of the features for the polymers in the different aging stages and provide access to choose the optimum characterization techniques. We believe that this review will attract the communities dedicated to materials science and chemistry.

17.
Angew Chem Int Ed Engl ; 62(15): e202216527, 2023 Apr 03.
Artículo en Inglés | MEDLINE | ID: mdl-36599818

RESUMEN

We reported a strategy of carbon-negative H2 production in which CO2 capture was coupled with H2 evolution at ambient temperature and pressure. For this purpose, carbonate-type Cux Mgy Fez layered double hydroxide (LDH) was preciously constructed, and then a photocatalysis reaction of interlayer CO3 2- reduction with glycerol oxidation was performed as driving force to induce the electron storage on LDH layers. With the participation of pre-stored electrons, CO2 was captured to recover interlayer CO3 2- in presence of H2 O, accompanied with equivalent H2 production. During photocatalysis reaction, Cu0.6 Mg1.4 Fe1 exhibited a decent CO evolution amount of 1.63 mmol g-1 and dihydroxyacetone yield of 3.81 mmol g-1 . In carbon-negative H2 production process, it showed an exciting CO2 capture quantity of 1.61 mmol g-1 and H2 yield of 1.44 mmol g-1 . Besides, this system possessed stable operation capability under simulated flu gas condition with negligible performance loss, exhibiting application prospect.

18.
J Clin Transl Hepatol ; 11(2): 341-349, 2023 Apr 28.
Artículo en Inglés | MEDLINE | ID: mdl-36643048

RESUMEN

Background and Aims: The study aimed to create a new staging model for radiotherapy-based treatment for prognostic hepatocellular carcinoma (HCC) classification. Methods: The training cohort comprised 658 patients receiving stereotactic body radiotherapy and external validation cohort comprised 533 patients receiving three-dimensional conformal radiotherapy and intensity-modulated radiotherapy. We established a modified staging system as follows: stage I, solitary nodule without macrovascular invasion, or 2-3 nodules no more than 3.0 cm apart, and performance status (PS) 0-2 (Ia: ALBI-1 grade; Ib: ALBI-2 or 3 grade); stage II: 2-3 nodules with any one nodule more than 3.0-cm apart, or ≥4 nodules, and performance status 0-2 (IIa: ALBI-1 grade; IIb: ALBI-2 grade); stage III: macrovascular invasion, regional lymph node metastasis or distant metastasis, and performance status 0-2 (IIIa: ALBI-1 grade; IIIb: ALBI-2 grade); stage IV: performance status 3-4, or performance status 0-2 with ALBI-3 grade. We analyzed long-term overall survival based on different stages. Results: The staging model showed an excellent ability to discriminate patients according to four stages and seven substages with notably different curves in the training and validation cohort. The median survival decreased from stages I to IV with 63.0 months in stage I (not reached in Ia, and 53.0 months in Ib), 24.0 months in stage II (28.0 months in IIa, and 22.0 months in IIb), 11.0 months in stage III (18.0 months in IIIa, and 9.0 months in IIIb), and less than 9.0 months in stage IV in the training cohort. Conclusions: The modified staging model may provide an alternative for clinical radiation oncologists.

19.
J Hazard Mater ; 447: 130723, 2023 Apr 05.
Artículo en Inglés | MEDLINE | ID: mdl-36640507

RESUMEN

The synthesized CaAl-layered double hydroxide (CaAl-LDH) shows excellent performance in potentially toxic metals (PTMs) removal, and the removal capacity of CaAl-LDH toward Cu2+, Zn2+ and Pb2+ in aqueous solution is 502.4, 315.2 and 600.0 mg/g respectively. Cu2+ and Zn2+ are removed through isomorphic substitution of laminate Ca and dissolution-reprecipitation, leading to the formation of CuAl-LDH and ZnAl-LDH mineralization products. Pb2+ is removed by the complexation and precipitation to form Pb3(CO3)2(OH)2. The application of CaAl-LDH in laboratory-scale soil remediation shows that target PTMs are gradually mineralized into relatively stable oxidizable and residual state, and the immobilization efficiency of available Cu, Zn, Cd and Pb reaches 84.62 %, 98.66 %, 96.81 % and 70.27 % respectively. In addition, practical application in farmland results in the significant reduction of available Cu, Zn, Cd and Pb with the immobilization efficiency of 30.15 %, 67.30 % and 57.80 % and 38.71 % respectively. Owing to the super-stable mineralization effect of CaAl-LDH, the content of PTMs in the roots, stems and grains of cultivated buckwheat also decreases obviously, and the growth and yield of buckwheat are not adversely affected but improved. The above prove that the super-stable mineralization based on CaAl-LDH is a promising scheme for the remediation of PTMs contaminated agriculture soil.

20.
J Contam Hydrol ; 253: 104127, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36587423

RESUMEN

Large deep lakes in plateau regions provide crucial ecosystem services but are susceptible to eutrophication due to their long water residence time. To date, the water quality of deep lakes has not received as much attention as that of shallow lakes owing to logistical challenges. This study investigated the seasonal variation and vertical distribution of phosphorus and related environmental variables in a large deep lake in the Yunnan Plateau, China (Fuxian Lake). Generally, the concentrations of total phosphorus (TP, R2 = 0.862), total dissolved phosphorus (TDP, R2 = 0.922), and dissolved inorganic phosphorus (DIP, R2 = 0.889) exhibited a linear increase with the greater water depth, whereas the pH and dissolved oxygen (DO) showed decreasing trends. The TP, TDP, and DIP values were 0.012, 0.006, and 0.004 mg/L, respectively, in surface waters (0.5 m depth), and increased to 0.074, 0.065, and 0.062 mg/L, respectively, at 140.0 m depth. The averaged over ordering method demonstrated that DO and air temperature accounted for a higher proportion of the explained variance of TP, TDP, and DIP in the shallow water layer (0.5-20.0 m). In contrast, DO and pH accounted for a higher proportion of the explained variance of TP, TDP, and DIP in deeper water layers (40.0-150.0 m). As a warm monomictic lake, the higher observed phosphorus concentrations in deeper water and sediment potentially pose a risk of future eutrophication in the Fuxian Lake. Our findings demonstrate that more efficient technical and management measures should be taken to reduce the external phosphorus load to Fuxian Lake, so that the load to and from the sediment will decrease eventually.


Asunto(s)
Lagos , Fósforo , Ecosistema , China , Eutrofización , Proteínas de Unión al ADN , Monitoreo del Ambiente , Nitrógeno/análisis
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